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Compare commits
1 Commits
boost-1.30
...
boost-1.25
| Author | SHA1 | Date | |
|---|---|---|---|
|
e4fe6f47de |
@@ -1,2 +0,0 @@
|
||||
bin*
|
||||
*.pdb
|
||||
@@ -1,53 +1,49 @@
|
||||
# (C) Copyright William E. Kempf 2001. Permission to copy, use, modify,
|
||||
# sell and distribute this software is granted provided this copyright
|
||||
# notice appears in all copies. This software is provided "as is" without
|
||||
# express or implied warranty, and with no claim as to its suitability for
|
||||
# any purpose.
|
||||
# (C) Copyright William E. Kempf 2001. Permission to copy, use, modify, sell and
|
||||
# distribute this software is granted provided this copyright notice appears
|
||||
# in all copies. This software is provided "as is" without express or implied
|
||||
# warranty, and with no claim as to its suitability for any purpose.
|
||||
#
|
||||
# Boost.Threads build Jamfile
|
||||
# Boost.Threads build and test Jamfile
|
||||
#
|
||||
# Additional configuration variables used:
|
||||
# 1. PTW32 may be used on Win32 platforms to specify that the pthreads-win32
|
||||
# library should be used instead of "native" threads. This feature is
|
||||
# mostly used for testing and it's generally recommended you use the
|
||||
# native threading libraries instead. PTW32 should be set to be a list
|
||||
# of two strings, the first specifying the installation path of the
|
||||
# pthreads-win32 library and the second specifying which library
|
||||
# variant to link against (see the pthreads-win32 documentation).
|
||||
# Example: jam -sPTW32="c:\pthreads-win32 pthreadVCE.lib"
|
||||
# Declares the following targets:
|
||||
# 1. libboost_thread, a static link library.
|
||||
# 1a. On Win32, a dynamic link library libboost_threadmon,
|
||||
# which must be used in conjunction with libboost_thread.
|
||||
|
||||
# Declare the location of this subproject relative to the root.
|
||||
# declare the location of this subproject relative to the root
|
||||
subproject libs/thread/build ;
|
||||
|
||||
# Include threads.jam for Boost.Threads global build information.
|
||||
# This greatly simplifies the Jam code needed to configure the build
|
||||
# for the various Win32 build types.
|
||||
SEARCH on <module@>threads.jam = $(SUBDIR) ;
|
||||
include <module@>threads.jam ;
|
||||
#######################
|
||||
|
||||
#
|
||||
# Declare the Boost.Threads static link library.
|
||||
#
|
||||
|
||||
# For Win32 we need to build a special DLL, libboost_threadmon, to handle
|
||||
# TSS destruction.
|
||||
if $(NT)
|
||||
{
|
||||
template thread_libs
|
||||
## sources ##
|
||||
: <template>thread_base
|
||||
## requirements ##
|
||||
:
|
||||
## default build ##
|
||||
: debug release
|
||||
;
|
||||
|
||||
# Base names of the source files for libboost_thread.
|
||||
CPP_SOURCES = condition mutex recursive_mutex thread tss xtime once
|
||||
exceptions threadmon ;
|
||||
|
||||
dll boost_thread
|
||||
: <template>thread_libs ../src/$(CPP_SOURCES).cpp
|
||||
: <define>BOOST_THREAD_BUILD_DLL=1
|
||||
;
|
||||
|
||||
stage bin-stage
|
||||
: <dll>boost_thread
|
||||
: #<tag><runtime-link-static>"s"
|
||||
<tag><debug>"d"
|
||||
: debug release
|
||||
;
|
||||
if $(PTW32)
|
||||
{
|
||||
PTW32_REQUIREMENTS = <define>BOOST_HAS_PTHREADS <define>PtW32NoCatchWarn ;
|
||||
}
|
||||
else
|
||||
{
|
||||
dll libboost_threadmon : ../src/threadmon.cpp
|
||||
# requirements
|
||||
: <include>$(BOOST_ROOT)
|
||||
<threading>multi
|
||||
: debug release ;
|
||||
}
|
||||
}
|
||||
|
||||
# Base names of the source files for libboost_thread
|
||||
CPP_SOURCES =
|
||||
condition mutex recursive_mutex thread tss xtime once exceptions ;
|
||||
|
||||
lib libboost_thread : ../src/$(CPP_SOURCES).cpp
|
||||
# requirements
|
||||
: <include>$(BOOST_ROOT)
|
||||
$(PTW32_REQUIREMENTS)
|
||||
<threading>multi
|
||||
: debug release ;
|
||||
|
||||
@@ -1,12 +0,0 @@
|
||||
|
||||
# Declare the uses system library
|
||||
lib pthread : : <name>pthread ;
|
||||
|
||||
project boost/thread
|
||||
: source-location ../src
|
||||
: usage-requirements <library>pthread
|
||||
;
|
||||
|
||||
CPP_SOURCES = condition mutex recursive_mutex thread tss xtime once exceptions ;
|
||||
|
||||
lib boost_thread : $(CPP_SOURCES).cpp ;
|
||||
@@ -1,29 +0,0 @@
|
||||
# Do some OS-specific setup
|
||||
{
|
||||
pthreads-win32 = ;
|
||||
|
||||
if $(NT)
|
||||
{
|
||||
if $(PTW32)
|
||||
{
|
||||
local install-path = $(PTW32[1]) ;
|
||||
local lib = $(PTW32[2]) ;
|
||||
pthreads-win32 =
|
||||
<define>BOOST_HAS_PTHREADS
|
||||
<define>PtW32NoCatchWarn
|
||||
<include>$(install-path)/pre-built/include
|
||||
<library-file>$(install-path)/pre-built/lib/$(lib)
|
||||
;
|
||||
}
|
||||
}
|
||||
|
||||
template thread_base
|
||||
## sources ##
|
||||
:
|
||||
## requirements ##
|
||||
: <sysinclude>$(BOOST_ROOT) <threading>multi $(pthreads-win32)
|
||||
<borland><*><cxxflags>-w-8004
|
||||
## default build ##
|
||||
:
|
||||
;
|
||||
}
|
||||
Binary file not shown.
77
doc/acknowledgements.html
Normal file
77
doc/acknowledgements.html
Normal file
@@ -0,0 +1,77 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=windows-1252">
|
||||
<meta name="GENERATOR" content="Microsoft FrontPage 4.0">
|
||||
<meta name="ProgId" content="FrontPage.Editor.Document">
|
||||
|
||||
<title>Boost.Threads Acknowledgements</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" text="#000000">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">Acknowledgements</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<h2>Acknowledgments</h2>
|
||||
|
||||
<p><a href="../../../people/william_kempf.htm">William E. Kempf</a> was
|
||||
the architect, designer, and implementor of <b>Boost.Threads</b>.</p>
|
||||
|
||||
<p>Important contributions were also made by Jeremy Siek (lots of input
|
||||
on the design and on the implementation), Alexander Terekhov (lots of
|
||||
input on the Win32 implementation, especially in regards to
|
||||
boost::condition, as well as a lot of explanation of POSIX behavior),
|
||||
Greg Colvin (lots of input on the design), and Paul Mclachlan, Thomas
|
||||
Matelich and Iain Hanson (for help in trying to get the build to work
|
||||
on other platforms).</p>
|
||||
|
||||
<p>The documentation was written by William E. Kempf. Beman Dawes
|
||||
provided additional documentation material and editing.</p>
|
||||
|
||||
<p>Discussions on the boost.org mailing list were essential in the
|
||||
development of <b>Boost.Threads</b>. As of August 1, 2001, participants
|
||||
included Alan Griffiths, Albrecht Fritzsche, Aleksey Gurtovoy,
|
||||
Alexander Terekhov, Andrew Green, Andy Sawyer, Asger Alstrup Nielsen,
|
||||
Beman Dawes, Bill Klein, Bill Rutiser, Bill Wade, Branko Èibej,
|
||||
Brent Verner, Craig Henderson, Csaba Szepesvari, Dale Peakall, Damian
|
||||
Dixon, Dan Nuffer, Darryl Green, Daryle Walker, David Abrahams, David
|
||||
Allan Finch, Dejan Jelovic, Dietmar Kuehl, Doug Gregor, Douglas Gregor,
|
||||
Duncan Harris, Ed Brey, Eric Swanson, Eugene Karpachov, Fabrice
|
||||
Truillot, Frank Gerlach, Gary Powell, Gernot Neppert, Geurt Vos, Ghazi
|
||||
Ramadan, Greg Colvin, Gregory Seidman, HYS, Iain Hanson, Ian Bruntlett,
|
||||
J Panzer, Jeff Garland, Jeff Paquette, Jens Maurer, Jeremy Siek, Jesse
|
||||
Jones, Joe Gottman, John (EBo) David, John Bandela, John Maddock, John
|
||||
Max Skaller, John Panzer, Jon Jagger , Karl Nelson, Kevlin Henney, KG
|
||||
Chandrasekhar, Levente Farkas, Lie-Quan Lee, Lois Goldthwaite, Luis
|
||||
Pedro Coelho, Marc Girod, Mark A. Borgerding, Mark Rodgers, Marshall
|
||||
Clow, Matthew Austern, Matthew Hurd, Michael D. Crawford, Michael H.
|
||||
Cox , Mike Haller, Miki Jovanovic, Nathan Myers, Paul Moore, Pavel
|
||||
Cisler, Peter Dimov, Petr Kocmid, Philip Nash, Rainer Deyke, Reid
|
||||
Sweatman, Ross Smith, Scott McCaskill, Shalom Reich , Steve Cleary,
|
||||
Steven Kirk, Thomas Holenstein, Thomas Matelich, Trevor Perrin,
|
||||
Valentin Bonnard, Vesa Karvonen, Wayne Miller, and William Kempf.</p>
|
||||
|
||||
<p>Apologies for anyone inadvertently missed.</p>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p>© <i>Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
@@ -1,69 +0,0 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Acknowledgments</title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Acknowledgments</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<p><a href="../../../people/william_kempf.htm">William E. Kempf</a> was the architect,
|
||||
designer, and implementor of <b>Boost.Threads</b>.</p>
|
||||
<p>Mac OS Carbon implementation written by <a href="../../../people/mac_murrett.htm">Mac
|
||||
Murrett</a>.</p>
|
||||
<p>Important contributions were also made by Jeremy Siek (lots of input on the
|
||||
design and on the implementation), Alexander Terekhov (lots of input on the
|
||||
Win32 implementation, especially in regards to boost::condition, as well as
|
||||
a lot of explanation of POSIX behavior), Greg Colvin (lots of input on the design),
|
||||
Paul Mclachlan, Thomas Matelich and Iain Hanson (for help in trying to get the
|
||||
build to work on other platforms), Kevin S. Van Horn (for several updates/corrections
|
||||
to the documentation), and Martin Johnson (shared library implementation).</p>
|
||||
<p>The documentation was written by William E. Kempf. Beman Dawes provided additional
|
||||
documentation material and editing.</p>
|
||||
<p>Discussions on the boost.org mailing list were essential in the development
|
||||
of <b>Boost.Threads</b>. As of August 1, 2001, participants included Alan Griffiths,
|
||||
Albrecht Fritzsche, Aleksey Gurtovoy, Alexander Terekhov, Andrew Green, Andy
|
||||
Sawyer, Asger Alstrup Nielsen, Beman Dawes, Bill Klein, Bill Rutiser, Bill Wade,
|
||||
Branko Èibej, Brent Verner, Craig Henderson, Csaba Szepesvari, Dale Peakall,
|
||||
Damian Dixon, Dan Nuffer, Darryl Green, Daryle Walker, David Abrahams, David
|
||||
Allan Finch, Dejan Jelovic, Dietmar Kuehl, Doug Gregor, Douglas Gregor, Duncan
|
||||
Harris, Ed Brey, Eric Swanson, Eugene Karpachov, Fabrice Truillot, Frank Gerlach,
|
||||
Gary Powell, Gernot Neppert, Geurt Vos, Ghazi Ramadan, Greg Colvin, Gregory
|
||||
Seidman, HYS, Iain Hanson, Ian Bruntlett, J Panzer, Jeff Garland, Jeff Paquette,
|
||||
Jens Maurer, Jeremy Siek, Jesse Jones, Joe Gottman, John (EBo) David, John Bandela,
|
||||
John Maddock, John Max Skaller, John Panzer, Jon Jagger , Karl Nelson, Kevlin
|
||||
Henney, KG Chandrasekhar, Levente Farkas, Lie-Quan Lee, Lois Goldthwaite, Luis
|
||||
Pedro Coelho, Marc Girod, Mark A. Borgerding, Mark Rodgers, Marshall Clow, Matthew
|
||||
Austern, Matthew Hurd, Michael D. Crawford, Michael H. Cox , Mike Haller, Miki
|
||||
Jovanovic, Nathan Myers, Paul Moore, Pavel Cisler, Peter Dimov, Petr Kocmid,
|
||||
Philip Nash, Rainer Deyke, Reid Sweatman, Ross Smith, Scott McCaskill, Shalom
|
||||
Reich , Steve Cleary, Steven Kirk, Thomas Holenstein, Thomas Matelich, Trevor
|
||||
Perrin, Valentin Bonnard, Vesa Karvonen, Wayne Miller, and William Kempf.</p>
|
||||
<p>Apologies for anyone inadvertently missed.</p>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
@@ -1,165 +1,222 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Bibliography</title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Bibliography</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<table summary="Bibliography" border="0" cellpadding="5" width="777">
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=windows-1252">
|
||||
<meta name="GENERATOR" content="Microsoft FrontPage 4.0">
|
||||
<meta name="ProgId" content="FrontPage.Editor.Document">
|
||||
|
||||
<title>Boost.Threads Bibliography</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" text="#000000">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">Bibliography</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<h2>Bibliography</h2>
|
||||
|
||||
<table summary="Bibliography" border="0" cellpadding="5" width="777">
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
"Andrews-83">Andrews 83</a>]</b></td>
|
||||
<td width="645"> Gregory R. Andrews, Fred B. Schneider, <cite>Concepts and
|
||||
Notations for Concurrent Programming</cite>, ACM Computing Surveys, Vol.
|
||||
15, No. 1, March, 1983. <a href=
|
||||
|
||||
<td width="645">
|
||||
Gregory R. Andrews, Fred B. Schneider, <cite>Concepts and
|
||||
Notations for Concurrent Programming</cite>, ACM Computing
|
||||
Surveys, Vol. 15, No. 1, March, 1983. <a href=
|
||||
"http://www.acm.org/pubs/citations/journals/surveys/1983-15-1/p3-andrews/">
|
||||
http://www.acm.org/pubs/citations/journals/surveys/1983-15-1/p3-andrews/</a>
|
||||
<p>Good general background reading. Includes descriptions of Path Expressions,
|
||||
Message Passing, and Remote Procedure Call in addition to the basics.</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
http://www.acm.org/pubs/citations/journals/surveys/1983-15-1/p3-andrews/</a>
|
||||
|
||||
|
||||
<p>Good general background reading. Includes descriptions
|
||||
of Path Expressions, Message Passing, and Remote Procedure
|
||||
Call in addition to the basics.</p>
|
||||
</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
"Boost">Boost</a>]</b></td>
|
||||
<td width="645"> The <cite>Boost</cite> worldwide web site. <a href=
|
||||
"http://www.boost.org">http://www.boost.org</a>
|
||||
<p>Boost.Threads is one of many Boost libraries. The Boost web site includes
|
||||
a great deal of documentation and general information which applies to
|
||||
all Boost libraries. Current copies of the libraries including documentation
|
||||
and test programs may be downloaded from the web site.</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
|
||||
<td width="645">
|
||||
The <cite>Boost</cite> world-wide web site. <a href=
|
||||
"http://www.boost.org">http://www.boost.org</a>
|
||||
|
||||
<p>Boost.Threads is one of many Boost libraries. The Boost
|
||||
web site includes a great deal of documentation and general
|
||||
information which applies to all Boost libraries. Current
|
||||
copies of the libraries including documentation and test
|
||||
programs may be downloaded from the web site.</p>
|
||||
</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
"Brinch-Hansen-73">Brinch Hansen 73</a>]</b></td>
|
||||
<td width="645"> Per Brinch Hansen, <cite>Concurrent Programming Concepts</cite>,
|
||||
ACM Computing Surveys, Vol. 5, No. 4, December, 1973. <a href=
|
||||
|
||||
<td width="645">
|
||||
Per Brinch Hansen, <cite>Concurrent Programming
|
||||
Concepts</cite>, ACM Computing Surveys, Vol. 5, No. 4,
|
||||
December, 1973. <a href=
|
||||
"http://www.acm.org/pubs/articles/journals/surveys/1973-5-4/p223-hansen/p223-hansen.pdf">
|
||||
http://www.acm.org/pubs/articles/journals/surveys/1973-5-4/p223-hansen/</a>
|
||||
<p>"This paper describes the evolution of language features for multiprogramming
|
||||
from event queues and semaphores to critical regions and monitors."
|
||||
Includes analysis of why <i>events</i> are considered error-prone. Also
|
||||
noteworthy because of an introductory quotation from Christopher Alexander;
|
||||
Brinch Hansen was years ahead of others in recognizing pattern concepts
|
||||
applied to software too.</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>]<a name=
|
||||
http://www.acm.org/pubs/articles/journals/surveys/1973-5-4/p223-hansen/</a>
|
||||
|
||||
|
||||
<p>"This paper describes the evolution of language
|
||||
features for multiprogramming from event queues and
|
||||
semaphores to critical regions and monitors." Includes
|
||||
analysis of why <i>events</i> are considered error-prone.
|
||||
Also noteworthy because of an introductory quotation from
|
||||
Christopher Alexander; Brinch Hansen was years ahead of
|
||||
others in recognizing pattern concepts applied to software
|
||||
too.</p>
|
||||
</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>]<a name=
|
||||
"Butenhof-97">Butenhof 97</a>]</b></td>
|
||||
<td width="645">
|
||||
<p>David R. Butenhof, <cite>Programming with POSIX Threads</cite>, Addison-Wesley
|
||||
1997, ISBN 0-201-63392-2 <a
|
||||
|
||||
<td width="645">
|
||||
<p>David R. Butenhof, <cite>Programming with POSIX
|
||||
Threads</cite>, Addison-Wesley 1997, ISBN 0-201-63392-2 <a
|
||||
href="http://cseng.aw.com/book/0,3828,0201633922,00.html">
|
||||
http://cseng.aw.com/book/0,3828,0201633922,00.html</a></p>
|
||||
<p>This is a very readable explanation of threads and how to use them. Many
|
||||
of the insights given apply to all multithreaded programming, not just
|
||||
POSIX Threads.</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
http://cseng.aw.com/book/0,3828,0201633922,00.html</a></p>
|
||||
|
||||
<p>This is a very readable explanation of threads and how
|
||||
to use them. Many of the insights given apply to all
|
||||
multi-threaded programming, not just POSIX Threads.</p>
|
||||
</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
"Hoare-74">Hoare 74</a>]</b></td>
|
||||
<td width="645">
|
||||
<p>C.A.R Hoare, <cite>Monitors: An Operating System Structuring Concept</cite>,
|
||||
Communications of the ACM, Vol. 17, No. 10. October 1974, pp. 549-557
|
||||
<a href=
|
||||
"http://www.acm.org/classics/feb96/"> http://www.acm.org/classics/feb96/</a></p>
|
||||
<p>Hoare and Brinch Hansen's work on Monitors is the basis for reliable
|
||||
multithreading patterns. This is one of the most often referenced papers
|
||||
in all of computer science, and with good reason.</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
|
||||
<td width="645">
|
||||
<p>C.A.R Hoare, <cite>Monitors: An Operating System
|
||||
Structuring Concept</cite>, Communications of the ACM, Vol.
|
||||
17, No. 10. October 1974, pp. 549-557 <a href=
|
||||
"http://www.acm.org/classics/feb96/">
|
||||
http://www.acm.org/classics/feb96/</a></p>
|
||||
|
||||
<p>Hoare and Brinch Hansen's work on Monitors is the
|
||||
basis for reliable multi-threading patterns. This is one of
|
||||
the most often referenced papers in all of computer
|
||||
science, and with good reason.</p>
|
||||
</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
"ISO-98">ISO 98</a>]</b></td>
|
||||
<td width="645">
|
||||
<p>ISO/IEC 14882:1998(E) <cite>Programming Language C++</cite> <a href="http://www.ansi.org">
|
||||
http://www.ansi.org</a></p>
|
||||
<p>This is the official C++ Standards document. Available from the ANSI
|
||||
(American National Standards Institute) Electronic Standards Store.</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
|
||||
<td width="645">
|
||||
<p>ISO/IEC 14882:1998(E) <cite>Programming Language
|
||||
C++</cite> <a href="http://www.ansi.org">
|
||||
http://www.ansi.org</a></p>
|
||||
|
||||
<p>This is the official C++ Standards document. Available
|
||||
from the ANSI (American National Standards Institute)
|
||||
Electronic Standards Store.</p>
|
||||
</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
"McDowell-89">McDowell 89</a>]</b></td>
|
||||
<td width="645"> Charles E McDowell, David P. Helmbold, <cite>Debugging Concurrent
|
||||
Programs</cite>, ACM Computing Surveys, Vol. 21, No. 2, December, 1989.
|
||||
<a href=
|
||||
|
||||
<td width="645">
|
||||
Charles E McDowell, David P. Helmbold, <cite>Debugging
|
||||
Concurrent Programs</cite>, ACM Computing Surveys, Vol. 21,
|
||||
No. 2, December, 1989. <a href=
|
||||
"http://www.acm.org/pubs/citations/journals/surveys/1989-21-4/p593-mcdowell/">
|
||||
http://www.acm.org/pubs/citations/journals/surveys/1989-21-4/p593-mcdowell/</a>
|
||||
<p>Identifies many of the unique failure modes and debugging difficulties
|
||||
associated with concurrent programs.</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
http://www.acm.org/pubs/citations/journals/surveys/1989-21-4/p593-mcdowell/</a>
|
||||
|
||||
|
||||
<p>Identifies many of the unique failure modes and
|
||||
debugging difficulties associated with concurrent
|
||||
programs.</p>
|
||||
</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
"Schmidt">Schmidt</a>]</b> </td>
|
||||
<td width="645">
|
||||
<p>Douglas C. Schmidt and Irfan Pyarali, <cite>Strategies for Implementing
|
||||
POSIX Condition Variables on Win32</cite>, Department of Computer Science,
|
||||
Washington University, St. Louis, Missouri. <a href=
|
||||
"http://www.cs.wustl.edu/~schmidt/win32-cv-1.html"> http://www.cs.wustl.edu/~schmidt/win32-cv-1.html</a></p>
|
||||
<p>Rationale for understanding Boost.Threads condition variables. Note that
|
||||
Alexander Terekhov found some bugs in the implementation given in this
|
||||
article, so pthreads-win32 and Boost.Threads are even more complicated
|
||||
yet.</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
|
||||
<td width="645">
|
||||
<p>Douglas C. Schmidt and Irfan Pyarali, <cite>Strategies
|
||||
for Implementing POSIX Condition Variables on Win32</cite>,
|
||||
Department of Computer Science, Washington University, St.
|
||||
Louis, Missouri. <a href=
|
||||
"http://www.cs.wustl.edu/~schmidt/win32-cv-1.html">
|
||||
http://www.cs.wustl.edu/~schmidt/win32-cv-1.html</a></p>
|
||||
|
||||
<p>Rationale for understanding Boost.Threads condition
|
||||
variables. Note that Alexander Terekhov found some bugs in
|
||||
the implementation given in this article, so pthreads-win32
|
||||
and Boost.Threads are even more complicated yet.</p>
|
||||
</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
"Schmidt-00">Schmidt 00</a>]</b> </td>
|
||||
<td width="645">
|
||||
<p>Douglas C. Schmidt, Michael Stal, Hans Rohnert and Frank Buschmann, <cite>Pattern-Oriented
|
||||
Software Architecture Volume 2 - Patterns for Concurrent and Networked
|
||||
Objects</cite>, Wiley 2000, ISBN 0-471-60695-2 <a href=
|
||||
|
||||
<td width="645">
|
||||
<p>Douglas C. Schmidt, Michael Stal, Hans Rohnert and Frank
|
||||
Buschmann, <cite>Pattern-Oriented Software Architecture
|
||||
Volume 2 - Patterns for Concurrent and Networked
|
||||
Objects</cite>, Wiley 2000, ISBN 0-471-60695-2 <a href=
|
||||
"http://www.wiley.com/Corporate/Website/Objects/Products/0,9049,104671,00.html">
|
||||
http://www.wiley.com/Corporate/Website/Objects/Products/0,9049,104671,00.html</a></p>
|
||||
<p>This is a very good explanation of how to apply several patterns useful
|
||||
for concurrent programming. Among the patterns documented is the Monitor
|
||||
Pattern mentioned frequently in the <b>Boost.Threads</b> documentation.</p>
|
||||
</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
http://www.wiley.com/Corporate/Website/Objects/Products/0,9049,104671,00.html</a></p>
|
||||
|
||||
<p>This is a very good explanation of how to apply several
|
||||
patterns useful for concurrent programming. Among the
|
||||
patterns documented is the Monitor Pattern mentioned
|
||||
frequently in the <b>Boost.Threads</b> documentation.</p>
|
||||
</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td width="102" valign="top" align="left"><b>[<a name=
|
||||
"Stroustrup-00">Stroustrup 00</a>]</b></td>
|
||||
<td width="645"> Bjarne Stroustrup, <cite>The C++ Programming Language</cite>,
|
||||
Special Edition, Addison-Wesley 2000, ISBN 0-201-70073-5 <a href=
|
||||
"http://cseng.aw.com/book/0,3828,0201700735,00.html"> http://cseng.aw.com/book/0,3828,0201700735,00.html</a>
|
||||
<p>The first book a C++ programmer should own. Note that the 3rd edition
|
||||
(and subsequent editions like the Special Edition) has been rewritten
|
||||
to cover the ISO standard language and library.</p>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<p>Note: The URL's above are provided in plain text form so that they will
|
||||
be visible on printed copies of this document.</p>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> and
|
||||
Beman Dawes 2001-2002. All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
|
||||
<td width="645">
|
||||
Bjarne Stroustrup, <cite>The C++ Programming
|
||||
Language</cite>, Special Edition, Addison-Wesley 2000, ISBN
|
||||
0-201-70073-5 <a href=
|
||||
"http://cseng.aw.com/book/0,3828,0201700735,00.html">
|
||||
http://cseng.aw.com/book/0,3828,0201700735,00.html</a>
|
||||
|
||||
<p>The first book a C++ programmer should own. Note that
|
||||
the 3rd edition (and subsequent editions like the Special
|
||||
Edition) has been rewritten to cover the ISO standard
|
||||
language and library.</p>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<p>Note: The URL's above are provided in plain text form so that
|
||||
they will be visible on printed copies of this document.</p>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %b %Y" startspan -->05 Nov 2001<!--webbot bot="Timestamp" endspan i-checksum="15246" --></p>
|
||||
|
||||
<p>© Copyright Beman Dawes, 2001</p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
@@ -1,77 +0,0 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>{{Library}} - Overview</title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Building and Testing</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<dl class="index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#topic1">First topic</a></dt>
|
||||
<dt><a href="#topic2">Second topic</a></dt>
|
||||
<dt><a href="#footnotes">Footnotes</a></dt>
|
||||
</dl>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>How you build the Boost.Threads libraries, and how you build your own applications
|
||||
that use those libraries, are some of the most frequently asked questions. Build
|
||||
processes are difficult to deal with in a portable manner. That's one reason
|
||||
why Boost.Threads makes use of <a href="../../../tools/build/index.html">Boost.Build</a>.
|
||||
In general you should refer to the documentation for <a href="../../../tools/build/index.html">Boost.Build</a>.
|
||||
This document will only supply you with some simple usage examples for how to
|
||||
use <em>bjam</em> to build and test Boost.Threads. In addition, this document
|
||||
will try and explain the build requirements so that users may create their own
|
||||
build processes (for instance, create an IDE specific project), both for building
|
||||
and testing Boost.Threads, as well as for building their own projects using
|
||||
Boost.Threads. </p>
|
||||
<h2><a name="topic1"></a>Building the Boost.Threads Libraries</h2>
|
||||
<p>To build the Boost.Thread libraries using Boost.Build, simply change to the
|
||||
directory <em>boost_root</em>/libs/thread/build and execute the command:</p>
|
||||
<pre>bjam -sTOOLS=<em>toolset</em></pre>
|
||||
<p>This will create four variants of the Boost.Threads library with the permuations
|
||||
of debug/release and runtime-link-dynamic/runtime-link-static. <em><strong>Note:</strong></em>
|
||||
Invoking the above command in <em>boost_root</em> will build all of the Boost
|
||||
distribution, including Boost.Threads.</p>
|
||||
<p>The Jamfile supplied with Boost.Threads produces a static library named <em>libboostthread</em>.
|
||||
In addition, on Win32 platforms a <em>boostthreadmon.dll</em> and a coresponding
|
||||
import library are created. The source files that are used to create the <em>libboostthread</em>
|
||||
library are all of the *.cpp files found in <em>boost_root</em>/libs/thread/src,
|
||||
except for <em>threadmon.cpp</em>. These need to be built with the compiler's
|
||||
and linker's multi-threading support enabled. On Win32 platforms the <em>boostthreadmon.dll</em>
|
||||
is created from <em>boost_root</em>/libs/thread/src/threadmon.cpp. This, too,
|
||||
needs to be built with the compiler's and linker's multi-threading support enabled.
|
||||
If you want to create your own build solution you'll have to follow these same
|
||||
guidelines. One of the most frequently reported problems when trying to do this
|
||||
occurs from not enabling the compiler's and linker's support for multi-threading.</p>
|
||||
<h2><a name="topic2"></a>Testing the Boost.Threads Libraries</h2>
|
||||
<p>To test the Boost.Threads libraries using Boost.Build, simply change to the
|
||||
directory <em>boost_root</em>/libs/thread/test and execute the command:</p>
|
||||
<pre><code>bjam -sTOOLS=<em>toolset</em> test</code></pre>
|
||||
<p> </p>
|
||||
<h2><a name="footnotes"></a>Footnotes</h2>
|
||||
<dl>
|
||||
<dt><a name="footnote1" class="footnote">(1)</a> {{text}}</dt>
|
||||
<dt><a name="footnote2" class="footnote">(2)</a> {{text}}</dt>
|
||||
</dl>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:{{address}}">{{author}}</a>
|
||||
2002. All Rights Reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
132
doc/call_once.html
Normal file
132
doc/call_once.html
Normal file
@@ -0,0 +1,132 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content=
|
||||
"threads, Boost.Threads, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, call_once</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">call_once</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#Synopsis">Synopsis</a><br>
|
||||
<a href="#Members">Members</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>The <code>call_once</code> routine and <code>once_flag</code> type
|
||||
can be used to run a routine exactly once. This can be used to
|
||||
initialize data in a <a href="definitions.html#Thread-safe">
|
||||
thread-safe</a> manner.</p>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/once.hpp"><boost/thread/once.hpp></a>
|
||||
</pre>
|
||||
|
||||
<h2><a name="Synopsis">Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost {
|
||||
|
||||
typedef <i>[implementation defined]</i> once_flag;
|
||||
const once_flag once_init = <i>[implementation defined]</i>;
|
||||
void call_once(void (*func)(), once_flag& flag);
|
||||
|
||||
} // namespace boost
|
||||
</pre>
|
||||
|
||||
<h2><a name="Reference">Reference</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>once_flag</h3>
|
||||
|
||||
<p>This implementation defined type is used as a flag to insure a
|
||||
routine is called only once. Instances of this type should be
|
||||
statically initialized to <code>once_init</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>once_init</h3>
|
||||
|
||||
<p>This is a constant value used to initialize <code>once_flag</code>
|
||||
instances to indicate that the logically associated routine has not
|
||||
been run yet.</p>
|
||||
<hr>
|
||||
|
||||
<h3>call_once</h3>
|
||||
<pre>
|
||||
void call_once(void (*func)(), once_flag& flag);
|
||||
</pre>
|
||||
|
||||
<p><b>Requires:</b> The function <code>func</code> shall not throw
|
||||
exceptions.</p>
|
||||
|
||||
<p><b>Effects:</b> As if (in an atomic fashion)</p>
|
||||
<code> if (flag == once_init)<br>
|
||||
func();</code>
|
||||
|
||||
<p><b>Postcondition:</b> <code>flag</code> != <code>
|
||||
once_init</code></p>
|
||||
<hr>
|
||||
|
||||
<h2><a name="Example">Example Usage</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/thread.hpp"><boost/thread/thread.hpp></a>
|
||||
#include <a href=
|
||||
"../../../boost/thread/tss.hpp"><boost/thread/once.hpp></a>
|
||||
#include <cassert>
|
||||
|
||||
int value=0;
|
||||
boost::once_flag once = boost::once_init;
|
||||
|
||||
void init()
|
||||
{
|
||||
++value;
|
||||
}
|
||||
|
||||
void thread_proc()
|
||||
{
|
||||
boost::call_once(&init, once);
|
||||
}
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
boost::thread_group threads;
|
||||
for (int i=0; i<5; ++i)
|
||||
threads.create_thread(&thread_proc);
|
||||
threads.join_all();
|
||||
assert(value == 1);
|
||||
}
|
||||
</pre>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
@@ -1,192 +1,321 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Header <boost/thread/condition.hpp></title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Header <<a href="../../../boost/thread/condition.hpp">boost/thread/condition.hpp</a>></h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<h2>Contents</h2>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#classes">Classes</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-condition">Class <code>condition</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-condition-synopsis">Class <code>condition</code> synopsis</a></dt>
|
||||
<dt><a href="#class-condition-ctors">Class <code>condition</code> constructors
|
||||
and destructor</a></dt>
|
||||
<dt><a href="#class-condition-modifiers">Class <code>condition</code> modifier
|
||||
functions</a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
<dt><a href="#examples">Example(s)</a></dt>
|
||||
</dl>
|
||||
<hr>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>Include the header <<a href="../../../boost/thread/condition.hpp">boost/thread/condition.hpp</a>>
|
||||
to define the class condition.</p>
|
||||
<h2><a name="classes"></a>Classes</h2>
|
||||
<h3><a name="class-condition"></a>Class <code>condition</code></h3>
|
||||
<p>An object of class <code>condition</code> is a synchronization primitive used
|
||||
to cause a thread to wait until a particular shared-data condition (or time)
|
||||
is met. A <code>condition</code> object is always used in conjunction with a
|
||||
mutex object (an object whose type is a model of <a href="mutex_concept.html">Mutex</a>
|
||||
or one of its refinements). The mutex object must be locked prior to waiting
|
||||
on the <code>condition</code>, which is verified by passing a lock object (an
|
||||
object whose type is a model of <a href="lock_concept.html">Lock</a> or one
|
||||
of its refinements) to the <code>condition</code> object's <code>wait</code>
|
||||
functions. Upon blocking on the condition object, the thread unlocks the mutex
|
||||
object. When the thread returns from a call to one of the condition object's
|
||||
wait functions the mutex object is again locked. The tricky unlock/lock sequence
|
||||
is performed automatically by the <code> condition</code> object's <code>wait</code>
|
||||
functions.</p>
|
||||
<p>The <code>condition</code> type is often used to implement the <i> Monitor
|
||||
Object</i> and other important patterns (see <a href="bibliography.html#Schmidt-00">[Schmidt
|
||||
00]</a> and <a href="bibliography.html#Hoare-74">[Hoare 74]</a>). Monitors are
|
||||
one of the most important patterns for creating reliable multithreaded programs.</p>
|
||||
<p>See <a href="definitions.html">Formal Definitions</a> for definitions of thread
|
||||
states <a href="definitions.html#state"> blocked</a> and <a href="definitions.html#state">ready</a>.
|
||||
Note that "waiting" is a synonym for blocked.</p>
|
||||
<h4><a name="class-condition-synopsis"></a>Class <code>condition</code> synopsis</h4>
|
||||
<pre>namespace boost
|
||||
{
|
||||
class condition : private <a href="../../utility/utility.htm#Class_noncopyable">boost::noncopyable</a> // Exposition only.
|
||||
// Class condition meets the <a href="overview.html#non-copyable">NonCopyable</a> requirement.
|
||||
{
|
||||
public:
|
||||
condition();
|
||||
~condition();
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
void notify_one();
|
||||
void notify_all();
|
||||
template <typename <a href="lock_concept.html#Lock-concept">Lock</a>>
|
||||
void wait(<a href="lock_concept.html#Lock-concept">Lock</a>& lock);
|
||||
template <typename <a href="lock_concept.html#Lock-concept">Lock</a>, typename <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>>
|
||||
void wait(<a href="lock_concept.html#Lock-concept">Lock</a>& lock, <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a> pred);
|
||||
template <typename <a href="lock_concept.html#Lock-concept">Lock</a>>
|
||||
bool timed_wait(<a href="lock_concept.html#Lock-concept">Lock</a>& lock, const xtime& xt);
|
||||
template <typename <a href="lock_concept.html#Lock-concept">Lock</a>, typename <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>>
|
||||
bool timed_wait(<a href="lock_concept.html#Lock-concept">Lock</a>& lock, const xtime& XT, <a href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a> pred);
|
||||
};
|
||||
};
|
||||
<title>Boost.Threads, condition</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#ffffff" link="#0000ff" vlink="#800080" text="#000000">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img height="86" alt="C++ Boost" src=
|
||||
"../../../c++boost.gif" width="277"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">condition</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#Synopsis">Synopsis</a><br>
|
||||
<a href="#Members">Members</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>An object of class <code>condition</code> is a synchronization
|
||||
primitive used to cause a thread to wait until a particular shared-data
|
||||
condition (or time) is met. A <code>condition</code> object is always
|
||||
used in conjunction with a mutex object modeling a <a href=
|
||||
"mutex_concept.html">Mutex Concept</a>. The mutex must be locked prior
|
||||
to waiting on the <code>condition</code>, which is ensured by passing a
|
||||
lock object modeling a <a href="lock_concept.html">Lock Concept</a> to
|
||||
the <code>condition</code> object's <code>wait</code> functions.
|
||||
While the thread is waiting on the <code>condition</code> object, the
|
||||
mutex associated with the lock is unlocked. When the thread returns
|
||||
from a call to one of the <code>condition</code> object's <code>
|
||||
wait</code> functions, the mutex is again locked. The tricky
|
||||
lock/unlock/lock sequence is performed automatically by the <code>
|
||||
condition</code> object's <code>wait</code> functions.</p>
|
||||
|
||||
<p>The <code>condition</code> type is often used to implement the <i>
|
||||
Monitor Object</i> and other important patterns. See <a href=
|
||||
"bibliography.html#Schmidt-00">[Schmidt-00]</a> and <a href=
|
||||
"bibliography.html#Hoare-74">[Hoare 74]</a>. Monitors are one of the
|
||||
most important patterns for creating reliable multithreaded
|
||||
programs.</p>
|
||||
|
||||
<p>See <a href="definitions.html">Formal Definitions</a> for
|
||||
definitions of thread states <a href="definitions.html#state">
|
||||
blocked</a> and <a href="definitions.html#state">ready</a>. Note that
|
||||
"waiting" is a synonym for blocked.</p>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/condition.hpp"><boost/thread/condition.hpp></a>
|
||||
</pre>
|
||||
<h4><a name="class-condition-ctors"></a>Class <code>condition</code> constructors
|
||||
and destructor</h4>
|
||||
<pre>condition();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Constructs a <code>condition</code> object.</dt>
|
||||
</dl>
|
||||
<pre>~condition();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Destroys <code>*this</code>.</dt>
|
||||
</dl>
|
||||
<h4><a name="class-condition-modifiers"></a>Class <code>condition</code> modifier
|
||||
functions</h4>
|
||||
<pre>void notify_one();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> If there is a thread waiting on <code>*this</code>, change
|
||||
that thread's state to ready. Otherwise there is no effect.</dt>
|
||||
<dt><b>Note:</b> If more than one thread is waiting on the condition, it is
|
||||
unspecified which is made ready. After returning to a ready state the notified
|
||||
thread must still acquire the mutex again (which occurs within the call to
|
||||
one of the <code>condition</code> object's wait functions).</dt>
|
||||
</dl>
|
||||
<pre>void notify_all();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Change the state of all threads waiting on <code> *this</code>
|
||||
to ready. If there are no waiting threads, <code> notify_all()</code> has
|
||||
no effect.</dt>
|
||||
</dl>
|
||||
<pre>template <typename ScopedLock>
|
||||
void wait(ScopedLock& lock);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> <code>ScopedLock</code> meets the <a href="lock_concept.html#ScopedLock">ScopedLock</a>
|
||||
requirements.</dt>
|
||||
<dt><b>Effects:</b> Releases the lock on the <a href="mutex_concept.html">mutex
|
||||
model</a> associated with <code>lock</code>, blocks the current thread of
|
||||
execution until readied by a call to <code>this->notify_one()</code> or
|
||||
<code> this->notify_all()</code>, and then reacquires the lock.</dt>
|
||||
<dt><b>Throws:</b> <code><a href="exceptions.html#class-lock_error">lock_error</a></code>
|
||||
if <code>!lock.locked()</code></dt>
|
||||
<dt><b>Danger:</b> This version should always be used within a loop checking
|
||||
that the state logically associated with the <code>condition</code> has become
|
||||
true. Without the loop, race conditions can ensue due to possible "spurious
|
||||
wake ups". The second version encapsulates this loop idiom internally
|
||||
and is generally the preferred method.</dt>
|
||||
</dl>
|
||||
<pre>Template<typename ScopedLock, typename Pr>
|
||||
void wait(ScopedLock& lock, Pr pred);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> <code>ScopedLock</code> meets the <a href="lock_concept.html#ScopedLock">ScopedLock</a>
|
||||
requirements, return from <code>pred()</code> convertible to bool.</dt>
|
||||
<dt><b>Effects:</b> As if: <code>while (!pred()) wait(lock)</code></dt>
|
||||
<dt><b>Throws:</b> <code><a href="exceptions.html#class-lock_error">lock_error</a></code>
|
||||
if <code>!lock.locked()</code></dt>
|
||||
</dl>
|
||||
<pre>template <typename ScopedLock>
|
||||
bool timed_wait(ScopedLock& lock, const <a href="xtime.html">xtime</a>& XT);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> <code>ScopedLock</code> meets the <a href="lock_concept.html#ScopedLock">ScopedLock</a>
|
||||
requirements.</dt>
|
||||
<dt><b>Effects:</b> Releases the lock on the <a href="mutex_concept.html">mutex
|
||||
model</a> associated with the <code> lock</code>, blocks the current thread
|
||||
of execution until readied by a call to <code>this->notify_one()</code>
|
||||
or <code> this->notify_all()</code>, or until <code>XT</code>, and then
|
||||
reacquires the lock.</dt>
|
||||
<dt><b>Returns:</b> <code>false</code> if <code>XT</code> is reached, otherwise
|
||||
<code>true</code>.</dt>
|
||||
<dt><b>Throws:</b> <code><a href="exceptions.html#class-lock_error">lock_error</a></code>
|
||||
if <code>!lock.locked()</code></dt>
|
||||
<dt><b>Danger:</b> This version should always be used within a loop checking
|
||||
that the state logically associated with the <code>condition</code> has become
|
||||
true. Without the loop, race conditions can ensue due to "spurious wake
|
||||
ups". The second version encapsulates this loop idiom internally and
|
||||
is generally the preferred method.</dt>
|
||||
</dl>
|
||||
<pre>Template<typename ScopedLock, typename Pr>
|
||||
bool timed_wait(ScopedLock& lock, const <a href="xtime.html">xtime</a>& XT, Pr pred);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> <code>ScopedLock</code> meets the <a href="lock_concept.html#ScopedLock">ScopedLock</a>
|
||||
requirements, return from <code>pred()</code> convertible to bool.</dt>
|
||||
<dt><b>Effects:</b> As if:<br>
|
||||
<pre>while (!pred())
|
||||
|
||||
<h2><a name="Synopsis">Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost {
|
||||
|
||||
class condition : private <a href=
|
||||
"../../utility/utility.htm#Class noncopyable">boost::noncopyable</a> // Exposition only.
|
||||
// Class condition meets the <a href=
|
||||
"overview.html#NonCopyable">NonCopyable</a> requirement.
|
||||
{
|
||||
if (!timed_wait(lock, XT))
|
||||
return false;
|
||||
}
|
||||
return true;
|
||||
public:
|
||||
condition();
|
||||
~condition();
|
||||
|
||||
void notify_one();
|
||||
void notify_all();
|
||||
template <typename <a href="scoped_lock.html">ScopedLock</a>>
|
||||
void wait(<a href="scoped_lock.html">ScopedLock</a>& lock);
|
||||
template <typename <a href="scoped_lock.html">ScopedLock</a>, typename <a
|
||||
href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>>
|
||||
void wait(<a href="scoped_lock.html">ScopedLock</a>& lock, <a href=
|
||||
"http://www.sgi.com/tech/stl/Predicate.html">Predicate</a> pred);
|
||||
template <typename <a href="scoped_lock.html">ScopedLock</a>>
|
||||
bool timed_wait(<a href=
|
||||
"scoped_lock.html">ScopedLock</a>& lock, const xtime& xt);
|
||||
template <typename <a href="scoped_lock.html">ScopedLock</a>, typename <a
|
||||
href="http://www.sgi.com/tech/stl/Predicate.html">Predicate</a>>
|
||||
bool timed_wait(<a href=
|
||||
"scoped_lock.html">ScopedLock</a>& lock, const xtime& xt, <a href=
|
||||
"http://www.sgi.com/tech/stl/Predicate.html">Predicate</a> pred);
|
||||
};
|
||||
|
||||
} // namespace boost
|
||||
</pre>
|
||||
</dt>
|
||||
<dt><b>Returns:</b> <code>false</code> if <code>XT</code> is reached, otherwise
|
||||
<code>true</code>.</dt>
|
||||
<dt><b>Throws:</b> <code><a href="exceptions.html#class-lock_error">lock_error</a></code>
|
||||
if <code>!lock.locked()</code></dt>
|
||||
</dl>
|
||||
<h2><a name="examples"></a>Example(s)</h2>
|
||||
<p><a href="../example/condition.cpp">libs/thread/example/condition.cpp</a></p>
|
||||
<p>Typical output (dependent on scheduling policies) is:</p>
|
||||
<pre>sent: 0
|
||||
|
||||
<h2><a name="Members">Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
condition();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Constructs a <code>condition</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~condition();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Destroys <code>*this</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>notify_one</h3>
|
||||
<pre>
|
||||
void notify_one();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> If there is a thread waiting on <code>*this</code>,
|
||||
change that thread's state to ready. Otherwise there is no
|
||||
effect.</p>
|
||||
|
||||
<p><b>Notes:</b> If more that one thread is waiting on the condition,
|
||||
it is unspecified which is made ready.</p>
|
||||
<hr>
|
||||
|
||||
<h3>notify_all</h3>
|
||||
<pre>
|
||||
void notify_all();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Change the state of all threads waiting on <code>
|
||||
*this</code> to ready. If there are no waiting threads, <code>
|
||||
notify_all()</code> has no effect.</p>
|
||||
<hr>
|
||||
|
||||
<h3>wait</h3>
|
||||
<pre>
|
||||
template <typename ScopedLock>
|
||||
void wait(ScopedLock& lock);
|
||||
</pre>
|
||||
|
||||
<p><b>Requires:</b> ScopedLock meets the <a href=
|
||||
"lock_concept.html#ScopedLock">ScopedLock</a> requirements.</p>
|
||||
|
||||
<p><b>Effects:</b> Releases the lock on the <a href=
|
||||
"mutex_concept.html">mutex model</a> associated with <code>lock</code>,
|
||||
blocks the current thread of execution until readied by a call to
|
||||
<code>this->notify_one()</code> or <code>
|
||||
this->notify_all()</code>, and then reacquires the lock. All effects
|
||||
occur in an atomic fashion.</p>
|
||||
|
||||
<p><b>Throws:</b> <code><a href="lock_error.html">lock_error</a></code>
|
||||
if <code>!lock.locked()</code></p>
|
||||
|
||||
<p><b>Danger:</b> This version should always be used within a loop
|
||||
checking that the state logically associated with the <code>
|
||||
condition</code> has become true. Without the loop, race conditions can
|
||||
ensue due to possible "spurious wake ups". The second version
|
||||
encapsulates this loop idiom internally and is generally the preferred
|
||||
method.</p>
|
||||
<pre>
|
||||
template <typename ScopedLock, typename Pr>
|
||||
void wait(ScopedLock& lock, Pr pred);
|
||||
</pre>
|
||||
|
||||
<p><b>Requires:</b> ScopedLock meets the <a href=
|
||||
"lock_concept.html#ScopedLock">ScopedLock</a> requirements, return from
|
||||
<code>pred()</code> convertible to bool.</p>
|
||||
|
||||
<p><b>Effects:</b> As if:</p>
|
||||
<code> while (!pred()) wait(lock)</code>
|
||||
|
||||
<p><b>Throws:</b> <code><a href="lock_error.html">lock_error</a></code>
|
||||
if <code>!lock.locked()</code></p>
|
||||
<hr>
|
||||
|
||||
<h3>timed_wait</h3>
|
||||
<pre>
|
||||
template <typename ScopedLock>
|
||||
bool timed_wait(ScopedLock& lock, const <a href=
|
||||
"xtime.html">xtime</a>& xt);
|
||||
</pre>
|
||||
|
||||
<p><b>Requires:</b> ScopedLock meets the <a href=
|
||||
"lock_concept.html#ScopedLock">ScopedLock</a>
|
||||
requirements.</p>
|
||||
|
||||
<p><b>Effects:</b> Releases the lock on the <a href=
|
||||
"mutex_concept.html">mutex model</a> associated with the <code>
|
||||
lock</code>, blocks the current thread of execution until readied by a
|
||||
call to <code>this->notify_one()</code> or <code>
|
||||
this->notify_all()</code>, or until <code>xt</code>, and then
|
||||
reacquires the lock. All effects occur in an atomic fashion.</p>
|
||||
|
||||
<p><b>Throws:</b> <code><a href="lock_error.html">lock_error</a></code>
|
||||
if <code>!lock.locked()</code></p>
|
||||
|
||||
<p><b>Danger:</b> This version should always be used within a loop
|
||||
checking that the state logically associated with the <code>
|
||||
condition</code> has become true. Without the loop, race conditions can
|
||||
ensue due to "spurious wake ups". The second version
|
||||
encapsulates this loop idiom internally and is generally the preferred
|
||||
method.</p>
|
||||
|
||||
<p><b>Returns:</b> <code>false</code> if <code>xt</code> is reached,
|
||||
otherwise <code>true</code>.</p>
|
||||
<pre>
|
||||
template <typename ScopedLock, typename Pr>
|
||||
bool timed_wait(ScopedLock& lock, const <a href=
|
||||
"xtime.html">xtime</a>& xt, Pr pred);
|
||||
</pre>
|
||||
|
||||
<p><b>Requires:</b> ScopedLock meets the <a href=
|
||||
"lock_concept.html#ScopedLock">ScopedLock</a> requirements,
|
||||
return from <code>pred()</code> convertible to bool.</p>
|
||||
|
||||
<p><b>Effects:</b> As if:</p>
|
||||
<code> while (!pred())<br>
|
||||
{<br>
|
||||
if (!timed_wait(lock, xt))<br>
|
||||
return
|
||||
false;<br>
|
||||
}</code>
|
||||
|
||||
<p><b>Throws:</b> <code><a href="lock_error.html">lock_error</a></code>
|
||||
if <code>!lock.locked()</code></p>
|
||||
|
||||
<p><b>Returns:</b> <code>false</code> if <code>xt</code> is reached,
|
||||
otherwise <code>true</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h2><a name="Example">Example Usage</a></h2>
|
||||
<pre>
|
||||
#include <iostream>
|
||||
#include <vector>
|
||||
#include <a href="../../../boost/utility.hpp"><boost/utility.hpp></a>
|
||||
#include <a href=
|
||||
"../../../boost/thread/condition.hpp"><boost/thread/condition.hpp></a>
|
||||
#include <a href=
|
||||
"../../../boost/thread/thread.hpp"><boost/thread/thread.hpp></a>
|
||||
|
||||
class bounded_buffer : private boost::noncopyable
|
||||
{
|
||||
public:
|
||||
typedef boost::mutex::scoped_lock lock;
|
||||
|
||||
bounded_buffer(int n) : begin(0), end(0), buffered(0), circular_buf(n) { }
|
||||
|
||||
void send (int m) {
|
||||
lock lk(monitor);
|
||||
while (buffered == circular_buf.size())
|
||||
buffer_not_full.wait(lk);
|
||||
circular_buf[end] = m;
|
||||
end = (end+1) % circular_buf.size();
|
||||
++buffered;
|
||||
buffer_not_empty.notify_one();
|
||||
}
|
||||
int receive() {
|
||||
lock lk(monitor);
|
||||
while (buffered == 0)
|
||||
buffer_not_empty.wait(lk);
|
||||
int i = circular_buf[begin];
|
||||
begin = (begin+1) % circular_buf.size();
|
||||
--buffered;
|
||||
buffer_not_full.notify_one();
|
||||
return i;
|
||||
}
|
||||
|
||||
private:
|
||||
int begin, end, buffered;
|
||||
std::vector<int> circular_buf;
|
||||
boost::condition buffer_not_full, buffer_not_empty;
|
||||
boost::mutex monitor;
|
||||
};
|
||||
|
||||
bounded_buffer buf(2);
|
||||
|
||||
void sender() {
|
||||
int n = 0;
|
||||
while (n < 100) {
|
||||
buf.send(n);
|
||||
std::cout << "sent: " << n << std::endl;
|
||||
++n;
|
||||
}
|
||||
buf.send(-1);
|
||||
}
|
||||
|
||||
void receiver() {
|
||||
int n;
|
||||
do {
|
||||
n = buf.receive();
|
||||
std::cout << "received: " << n << std::endl;
|
||||
} while (n != -1); // -1 indicates end of buffer
|
||||
}
|
||||
|
||||
int main(int, char*[])
|
||||
{
|
||||
boost::thread thrd1(&sender);
|
||||
boost::thread thrd2(&receiver);
|
||||
thrd1.join();
|
||||
thrd2.join();
|
||||
return 0;
|
||||
}
|
||||
</pre>
|
||||
|
||||
<p>Typical output (dependent on scheduling policies) is:</p>
|
||||
<pre>
|
||||
sent: 0
|
||||
sent: 1
|
||||
received: 0
|
||||
received: 1
|
||||
@@ -197,16 +326,13 @@ received: 3
|
||||
sent: 4
|
||||
received: 4
|
||||
</pre>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->09 January, 2003<!--webbot bot="Timestamp" endspan i-checksum="38582" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
97
doc/config.html
Normal file
97
doc/config.html
Normal file
@@ -0,0 +1,97 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
|
||||
<title>Boost.Threads, Configuration Information</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">Configuration Information</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><b>Boost.Threads</b> uses several configuration macros in <a href=
|
||||
"../../config/config.htm"><boost/config.hpp></a>. These macros
|
||||
are documented here. Most of the macros are of interest only to
|
||||
developers attempting to provide new implementations of <b>
|
||||
Boost.Threads</b>. The one exception to this is BOOST_HAS_THREADS.</p>
|
||||
|
||||
<table summary="macros" cellspacing="10" width="100%">
|
||||
<tr>
|
||||
<td valign="top"><b>Macro</b> </td>
|
||||
|
||||
<td valign="top"><b>Meaning</b> </td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top">BOOST_HAS_THREADS</td>
|
||||
|
||||
<td valign="top">Indicates that threading support is available.
|
||||
This means both that there is a platform specific
|
||||
implementation for <b>Boost.Threads</b> and that threading
|
||||
support has been enabled in a platform specific manner. For
|
||||
instance, on the Win32 platform there's an implementation
|
||||
for <b>Boost.Threads</b> but unless the program is compiled
|
||||
against one of the multi-threading runtimes (often determined
|
||||
by the compiler predefining the macro _MT) the
|
||||
BOOST_HAS_THREADS macro remains undefined.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top">BOOST_HAS_WINTHREADS</td>
|
||||
|
||||
<td valign="top">Indicates that the platform has the Microsoft
|
||||
Win32 threading libraries, and that they should be used to
|
||||
implement <b>Boost.Threads</b>.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top">BOOST_HAS_PTHREADS</td>
|
||||
|
||||
<td valign="top">Indicates that the platform has the POSIX
|
||||
pthreads libraries, and that they should be used to implement
|
||||
<b>Boost.Threads</b>.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top">BOOST_HAS_FTIME</td>
|
||||
|
||||
<td valign="top">Indicates that the implementation should use
|
||||
GetSystemTimeAsFileTime() and the FILETIME type to calculate
|
||||
the current time. This is an implementation detail used by
|
||||
boost::detail::getcurtime().</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top">BOOST_HAS_GETTTIMEOFDAY</td>
|
||||
|
||||
<td valign="top">Indicates that the implementation should use
|
||||
gettimeofday() to calculate the current time. This is an
|
||||
implementation detail used by boost::detail::getcurtime().</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
@@ -1,94 +0,0 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Configuration</title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Configuration</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#lib-defined-public">Public Library Defined Macros</a></dt>
|
||||
<dt><a href="#lib-defined-impl">Library Defined Implementation Macros</a></dt>
|
||||
</dl>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p><b>Boost.Threads</b> uses several configuration macros in <a href="../../config/config.htm"><boost/config.hpp></a>,
|
||||
as well as configuration macros meant to be supplied by the application. These
|
||||
macros are documented here.</p>
|
||||
<h2><a name="lib-defined-public"></a>Public Library Defined Macros</h2>
|
||||
<p>These macros are defined by <b>Boost.Threads</b> but are expected to be used
|
||||
by application code.</p>
|
||||
<table summary="public library defined macros" cellspacing="10" width="100%">
|
||||
<tr>
|
||||
<td><b>Macro</b></td>
|
||||
<td><b>Meaning</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>BOOST_HAS_THREADS</td>
|
||||
<td>Indicates that threading support is available. This means both that there
|
||||
is a platform specific implementation for <b>Boost.Threads</b> and that
|
||||
threading support has been enabled in a platform specific manner. For instance,
|
||||
on the Win32 platform there's an implementation for <b>Boost.Threads</b>
|
||||
but unless the program is compiled against one of the multithreading runtimes
|
||||
(often determined by the compiler predefining the macro _MT) the BOOST_HAS_THREADS
|
||||
macro remains undefined.</td>
|
||||
</tr>
|
||||
</table>
|
||||
<h2><a name="lib-defined-impl"></a>Library Defined Implementation Macros</h2>
|
||||
<p>These macros are defined by <b>Boost.Threads</b> and are implementation details
|
||||
of interest only to implementors.</p>
|
||||
<table summary="library defined implementation macros" cellspacing="10" width="100%">
|
||||
<tr>
|
||||
<td><b>Macro</b></td>
|
||||
<td><b>Meaning</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>BOOST_HAS_WINTHREADS</td>
|
||||
<td>Indicates that the platform has the Microsoft Win32 threading libraries,
|
||||
and that they should be used to implement <b>Boost.Threads</b>.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>BOOST_HAS_PTHREADS</td>
|
||||
<td>Indicates that the platform has the POSIX pthreads libraries, and that
|
||||
they should be used to implement <b>Boost.Threads</b>.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>BOOST_HAS_FTIME</td>
|
||||
<td>Indicates that the implementation should use GetSystemTimeAsFileTime()
|
||||
and the FILETIME type to calculate the current time. This is an implementation
|
||||
detail used by boost::detail::getcurtime().</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>BOOST_HAS_GETTTIMEOFDAY</td>
|
||||
<td>Indicates that the implementation should use gettimeofday() to calculate
|
||||
the current time. This is an implementation detail used by boost::detail::getcurtime().</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
@@ -1,262 +1,348 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Definitions</title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Definitions</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<h2>Contents</h2>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#definitions">Definitions</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#definition-thread">Thread</a></dt>
|
||||
<dt><a href="#definition-thread-safe">Thread-safe</a></dt>
|
||||
<dt><a href="#definition-thread-state">Thread State</a></dt>
|
||||
<dt><a href="#definition-race-condition">Race Condition</a></dt>
|
||||
<dt><a href="#definition-deadlock">Deadlock</a></dt>
|
||||
<dt><a href="#definition-starvation">Starvation</a></dt>
|
||||
<dt><a href="#definition-priority-failure">Priority Failure</a></dt>
|
||||
<dt><a href="#definition-visibility">Memory Visibility</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#acknowledgements">Acknowledgments</a></dt>
|
||||
</dl>
|
||||
<hr>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>The definitions are given in terms of the <a href=
|
||||
<head>
|
||||
<meta http-equiv="Content-Language" content="en-us">
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=windows-1252">
|
||||
<meta name="GENERATOR" content="Microsoft FrontPage 4.0">
|
||||
<meta name="ProgId" content="FrontPage.Editor.Document">
|
||||
|
||||
<title>Boost.Threads Definitions</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">Definitions</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<h2>Introduction</h2>
|
||||
|
||||
<p>The definitions are given in terms of the <a href=
|
||||
"bibliography.html#ISO-98">C++ Standard</a>. References to the standard
|
||||
are in the form [1.2.3/4], which represents the section number, with the paragraph
|
||||
number following the "/".</p>
|
||||
<p>Because the definitions are written in something akin to "standardese",
|
||||
they can be difficult to understand. The intent isn't to confuse, but rather
|
||||
to clarify the additional requirements Boost.Threads places on a C++ implementation
|
||||
as defined by the C++ Standard.</p>
|
||||
<h2><a name="definitions"></a>Definitions</h2>
|
||||
<h3><a name="definition-thread"></a>Thread</h3>
|
||||
<p>Thread is short for "thread of execution". A thread of execution
|
||||
is an execution environment [1.9/7] within the execution environment of a C++
|
||||
program [1.9]. The main() function [3.6.1] of the program is the initial function
|
||||
of the initial thread. A program in a multithreading environment always has
|
||||
an initial thread even if the program explicitly creates no additional threads.</p>
|
||||
<p>Unless otherwise specified, each thread shares all aspects of its execution
|
||||
environment with other threads in the program. Shared aspects of the execution
|
||||
environment include, but are not limited to, the following:</p>
|
||||
<ul>
|
||||
<li>Static storage duration (static, extern) objects [3.7.1].</li>
|
||||
</ul>
|
||||
<ul>
|
||||
<li>Dynamic storage duration (heap) objects [3.7.3]. Thus each memory allocation
|
||||
will return a unique addresses, regardless of the thread making the allocation
|
||||
request.</li>
|
||||
</ul>
|
||||
<ul>
|
||||
<li>Automatic storage duration (stack) objects [3.7.2] accessed via pointer
|
||||
or reference from another thread.</li>
|
||||
</ul>
|
||||
<ul>
|
||||
<li>Resources provided by the operating system. For example, files.</li>
|
||||
</ul>
|
||||
<ul>
|
||||
<li>The program itself. In other words, each thread is executing some function
|
||||
of the same program, not a totally different program.</li>
|
||||
</ul>
|
||||
<p>Each thread has its own:</p>
|
||||
<ul>
|
||||
<li>Registers and current execution sequence (program counter) [1.9/5].</li>
|
||||
</ul>
|
||||
<ul>
|
||||
<li>Automatic storage duration (stack) objects [3.7.2].</li>
|
||||
</ul>
|
||||
<h3><a name="definition-thread-safe"></a>Thread-safe</h3>
|
||||
<p>A program is thread-safe if it has no <a href="#Race condition">race conditions</a>,
|
||||
does not <a href="#Deadlock">deadlock</a>, and has no <a href="#Priority failure">priority
|
||||
failures</a>.</p>
|
||||
<p>Note that thread-safety does not necessarily imply efficiency, and than while
|
||||
some thread-safety violations can be determined statically at compile time,
|
||||
many thread-safety errors can only only be detected at runtime.</p>
|
||||
<h3><a name="definition-thread-state"></a>Thread State</h3>
|
||||
<p>During the lifetime of a thread, it shall be in one of the following states:</p>
|
||||
<table summary="thread states" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>State</b></td>
|
||||
<td><b>Description</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>Ready</td>
|
||||
<td>Ready to run, but waiting for a processor.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>Running</td>
|
||||
<td>Currently executing on a processor. Zero or more threads may be running
|
||||
at any time, with a maximum equal to the number of processors.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>Blocked</td>
|
||||
<td>Waiting for some resource other than a processor which is not currently
|
||||
available, or for the completion of calls to library functions [1.9/6].
|
||||
The term "waiting" is synonymous for "blocked"</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>Terminated</td>
|
||||
<td>Finished execution but not yet detached or joined.</td>
|
||||
</tr>
|
||||
</table>
|
||||
<p>Thread state transitions shall occur only as specified:</p>
|
||||
<table summary="state transitions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>From</b></td>
|
||||
<td><b>To</b></td>
|
||||
<td><b>Cause</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>
|
||||
<p align="left">[none]</p>
|
||||
</td>
|
||||
<td>Ready</td>
|
||||
<td>Thread is created by a call to a library function. In the case of the
|
||||
initial thread, creation is implicit and occurs during the startup of the
|
||||
main() function [3.6.1].</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>Ready</td>
|
||||
<td>Running</td>
|
||||
<td>Processor becomes available.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>Running</td>
|
||||
<td>Ready</td>
|
||||
<td>Thread preempted.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>Running</td>
|
||||
<td>Blocked</td>
|
||||
<td>Thread calls a library function which waits for a resource or for the
|
||||
completion of I/O.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>Running</td>
|
||||
<td>Terminated</td>
|
||||
<td>Thread returns from its initial function, calls a thread termination library
|
||||
function, or is canceled by some other thread calling a thread termination
|
||||
library function.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>Blocked</td>
|
||||
<td>Ready</td>
|
||||
<td>The resource being waited for becomes available, or the blocking library
|
||||
function completes.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>Terminated</td>
|
||||
<td>[none]</td>
|
||||
<td>Thread is detached or joined by some other thread calling the appropriate
|
||||
library function, or by program termination [3.6.3].</td>
|
||||
</tr>
|
||||
</table>
|
||||
<p>[Note: if a suspend() function is added to the threading library, additional
|
||||
transitions to the blocked state will have to be added to the above table.]</p>
|
||||
<h3><a name="definition-race-condition"></a>Race Condition</h3>
|
||||
<p>A race condition is what occurs when multiple threads read and write to the
|
||||
same memory without proper synchronization, resulting in an incorrect value
|
||||
being read or written. The result of a race condition may be a bit pattern which
|
||||
isn't even a valid value for the data type. A race condition results in
|
||||
undefined behavior [1.3.12].</p>
|
||||
<p>Race conditions can be prevented by serializing memory access using the tools
|
||||
provided by Boost.Threads.</p>
|
||||
<h3><a name="definition-deadlock"></a>Deadlock</h3>
|
||||
<p>Deadlock is an execution state where for some set of threads, each thread in
|
||||
the set is blocked waiting for some action by one of the other threads in the
|
||||
set. Since each is waiting on the others, none will ever become ready again.</p>
|
||||
<h3><a name="definition-starvation"></a>Starvation</h3>
|
||||
<p>The condition in which a thread is not making sufficient progress in its work
|
||||
during a given time interval.</p>
|
||||
<h3><a name="definition-priority-failure"></a>Priority Failure</h3>
|
||||
<p>A priority failure (such as priority inversion or infinite overtaking) occurs
|
||||
when threads executed in such a sequence that required work is not performed
|
||||
in time to be useful.</p>
|
||||
<h3><a name="definition-visibility"></a>Memory Visibility</h3>
|
||||
<p>An address [1.7] shall always point to the same memory byte, regardless of
|
||||
the thread or processor dereferencing the address.</p>
|
||||
<p>An object [1.8, 1.9] is accessible from multiple threads if it is of static
|
||||
storage duration (static, extern) [3.7.1], or if a pointer or reference to it
|
||||
is explicitly or implicitly dereferenced in multiple threads.</p>
|
||||
<p>For an object accessible from multiple threads, the value of the object accessed
|
||||
from one thread may be indeterminate or different than the value accessed from
|
||||
another thread, except under the conditions specified in the following table.
|
||||
For the same row of the table, the value of an object accessible at the indicated
|
||||
sequence point in thread A will be determinate and the same if accessed at or
|
||||
after the indicated sequence point in thread B, provided the object is not otherwise
|
||||
modified. In the table, the "sequence point at a call" is the sequence
|
||||
point after the evaluation of all function arguments [1.9/17], while the "sequence
|
||||
point after a call" is the sequence point after the copying of the returned
|
||||
value..." [1.9/17].</p>
|
||||
<table summary="memory visibility" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td align="center"><b>Thread A</b></td>
|
||||
<td align="center"><b>Thread B</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>The sequence point at a call to a library thread-creation function.</td>
|
||||
<td>The first sequence point of the initial function in the new thread created
|
||||
by the Thread A call.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>The sequence point at a call to a library function which locks a mutex,
|
||||
directly or by waiting for a condition variable.</td>
|
||||
<td>The sequence point after a call to a library function which unlocks the
|
||||
same mutex.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>The last sequence point before thread termination.</td>
|
||||
<td>The sequence point after a call to a library function which joins the
|
||||
terminated thread.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td>The sequence point at a call to a library function which signals or broadcasts
|
||||
a condition variable.</td>
|
||||
<td>The sequence point after the call to the library function which was waiting
|
||||
on that same condition variable or signal.</td>
|
||||
</tr>
|
||||
</table>
|
||||
<p>The architecture of the execution environment and the observable behavior of
|
||||
the abstract machine [1.9] shall be the same on all processors.</p>
|
||||
<p>The latitude granted by the C++ standard for an implementation to alter the
|
||||
definition of observable behavior of the abstract machine to include additional
|
||||
library I/O functions [1.9/6] is extended to include threading library functions.</p>
|
||||
<p>When an exception is thrown and there is no matching exception handler in the
|
||||
same thread, behavior is undefined. The preferred behavior is the same as when
|
||||
there is no matching exception handler in a program [15.3/9]. That is, terminate()
|
||||
is called, and it is implementation defined whether or not the stack is unwound.</p>
|
||||
<h2><a name="acknowledgements"></a>Acknowledgments</h2>
|
||||
<p>This document was originally written by Beman Dawes, and then much improved by the incorporation of comments from
|
||||
William Kempf, who now maintains the contents.</p>
|
||||
<p>The visibility rules are based on <a href=
|
||||
are in the form [1.2.3/4], which represents the section number, with
|
||||
the paragraph number following the "/".</p>
|
||||
|
||||
<p>Because the definitions are written in something akin to
|
||||
"standardese", they can be difficult to understand. The
|
||||
intent isn't to confuse, but rather to clarify the additional
|
||||
requirements Boost.Threads places on a C++ implementation as defined by
|
||||
the C++ Standard.</p>
|
||||
|
||||
<h2>Definitions</h2>
|
||||
|
||||
<h3>Thread</h3>
|
||||
|
||||
<p>Thread is short for "thread of execution". A thread of
|
||||
execution is an execution environment [1.9/7] within the execution
|
||||
environment of a C++ program [1.9]. The main() function [3.6.1] of the
|
||||
program is the initial function of the initial thread. A program in a
|
||||
multi-threading environment always has an initial thread even if the
|
||||
program explicitly creates no additional threads.</p>
|
||||
|
||||
<p>Unless otherwise specified, each thread shares all aspects of its
|
||||
execution environment with other threads in the program. Shared aspects
|
||||
of the execution environment include, but are not limited to, the
|
||||
following:</p>
|
||||
|
||||
<ul>
|
||||
<li>Static storage duration (static, extern) objects [3.7.1].</li>
|
||||
</ul>
|
||||
|
||||
<ul>
|
||||
<li>Dynamic storage duration (heap) objects [3.7.3]. Thus each
|
||||
memory allocation will return a unique addresses, regardless of the
|
||||
thread making the allocation request.</li>
|
||||
</ul>
|
||||
|
||||
<ul>
|
||||
<li>Automatic storage duration (stack) objects [3.7.2] accessed via
|
||||
pointer or reference from another thread.</li>
|
||||
</ul>
|
||||
|
||||
<ul>
|
||||
<li>Resources provided by the operating system. For example,
|
||||
files.</li>
|
||||
</ul>
|
||||
|
||||
<ul>
|
||||
<li>The program itself. In other words, each thread is executing
|
||||
some function of the same program, not a totally different
|
||||
program.</li>
|
||||
</ul>
|
||||
|
||||
<p>Each thread has its own:</p>
|
||||
|
||||
<ul>
|
||||
<li>Registers and current execution sequence (program counter)
|
||||
[1.9/5].</li>
|
||||
</ul>
|
||||
|
||||
<ul>
|
||||
<li>Automatic storage duration (stack) objects [3.7.2].</li>
|
||||
</ul>
|
||||
|
||||
<h3><a name="Thread-safe">Thread-safe</a></h3>
|
||||
|
||||
<p>A program is thread-safe if it has no <a href="#Race condition">race
|
||||
conditions</a>, does not <a href="#Deadlock">deadlock</a>, and has no
|
||||
<a href="#Priority failure">priority failures</a>.</p>
|
||||
|
||||
<p>Note that thread-safety does not necessarily imply efficiency, and
|
||||
than while some thread-safety violations can be determined statically
|
||||
at compile time, many thread-safety errors can only only be detected at
|
||||
runtime.</p>
|
||||
|
||||
<h3>Thread <a name="State">State</a></h3>
|
||||
|
||||
<p>During the lifetime of a thread, it shall be in one of the following
|
||||
states:</p>
|
||||
|
||||
<table summary="thread states" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>State</b></td>
|
||||
|
||||
<td><b>Description</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Ready</td>
|
||||
|
||||
<td>Ready to run, but waiting for a processor.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Running</td>
|
||||
|
||||
<td>Currently executing on a processor. Zero or more threads
|
||||
may be running at any time, with a maximum equal to the number
|
||||
of processors.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Blocked</td>
|
||||
|
||||
<td>Waiting for some resource other than a processor which is
|
||||
not currently available, or for the completion of calls to
|
||||
library functions [1.9/6]. The term "waiting" is
|
||||
synonymous for "blocked"</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Terminated</td>
|
||||
|
||||
<td>Finished execution but not yet detached or joined.</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<p>Thread state transitions shall occur only as specified:</p>
|
||||
|
||||
<table summary="state transitions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>From</b></td>
|
||||
|
||||
<td><b>To</b></td>
|
||||
|
||||
<td><b>Cause</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>
|
||||
<p align="left">[none]</p>
|
||||
</td>
|
||||
|
||||
<td>Ready</td>
|
||||
|
||||
<td>Thread is created by a call to a library function. In the
|
||||
case of the initial thread, creation is implicit and occurs
|
||||
during the startup of the main() function [3.6.1].</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Ready</td>
|
||||
|
||||
<td>Running</td>
|
||||
|
||||
<td>Processor becomes available.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Running</td>
|
||||
|
||||
<td>Ready</td>
|
||||
|
||||
<td>Thread preempted.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Running</td>
|
||||
|
||||
<td>Blocked</td>
|
||||
|
||||
<td>Thread calls a library function which waits for a resource
|
||||
or for the completion of I/O.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Running</td>
|
||||
|
||||
<td>Terminated</td>
|
||||
|
||||
<td>Thread returns from its initial function, calls a thread
|
||||
termination library function, or is cancelled by some other
|
||||
thread calling a thread termination library function.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Blocked</td>
|
||||
|
||||
<td>Ready</td>
|
||||
|
||||
<td>The resource being waited for becomes available, or the
|
||||
blocking library function completes.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Terminated</td>
|
||||
|
||||
<td>[none]</td>
|
||||
|
||||
<td>Thread is detached or joined by some other thread calling
|
||||
the appropriate library function, or by program termination
|
||||
[3.6.3].</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<p>[Note: if a suspend() function is added to the threading library,
|
||||
additional transitions to the blocked state will have to be added to
|
||||
the above table.]</p>
|
||||
|
||||
<h3><a name="Race condition">Race condition</a></h3>
|
||||
|
||||
<p>A race condition is what occurs when multiple threads read and write
|
||||
to the same memory without proper synchronization, resulting in an
|
||||
incorrect value being read or written. The result of a race condition
|
||||
may be a bit pattern which isn't even a valid value for the data
|
||||
type. A race condition results in undefined behavior [1.3.12].</p>
|
||||
|
||||
<p>Race conditions can be prevented by serializing memory access using
|
||||
the tools provided by Boost.Threads.</p>
|
||||
|
||||
<h3><a name="Deadlock">Deadlock</a></h3>
|
||||
|
||||
<p>Deadlock is an execution state where for some set of threads, each
|
||||
thread in the set is blocked waiting for some action by one of the
|
||||
other threads in the set. Since each is waiting on the others, none
|
||||
will ever become ready again.</p>
|
||||
|
||||
<h3><a name="Priority failure">Priority failure</a></h3>
|
||||
|
||||
<p>A priority failure (such as priority inversion or infinite
|
||||
overtaking) occurs when threads executed in such a sequence that
|
||||
required work is not performed in time to be useful.</p>
|
||||
|
||||
<h2>Memory visibility between threads</h2>
|
||||
|
||||
<p>An address [1.7] shall always point to the same memory byte,
|
||||
regardless of the thread or processor dereferencing the address.</p>
|
||||
|
||||
<p>An object [1.8, 1.9] is accessible from multiple threads if it is of
|
||||
static storage duration (static, extern) [3.7.1], or if a pointer or
|
||||
reference to it is explicitly or implicitly dereferenced in multiple
|
||||
threads.</p>
|
||||
|
||||
<p>For an object accessible from multiple threads, the value of the
|
||||
object accessed from one thread may be indeterminate or different than
|
||||
the value accessed from another thread, except under the conditions
|
||||
specified in the following table. For the same row of the table, the
|
||||
value of an object accessible at the indicated sequence point in thread
|
||||
A will be determinate and the same if accessed at or after the
|
||||
indicated sequence point in thread B, provided the object is not
|
||||
otherwise modified. In the table, the "sequence point at a
|
||||
call" is the sequence point after the evaluation of all function
|
||||
arguments [1.9/17], while the "sequence point after a call"
|
||||
is the sequence point after the copying of the returned value..."
|
||||
[1.9/17].</p>
|
||||
|
||||
<table summary="memory visibility" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td align="center"><b>Thread A</b></td>
|
||||
|
||||
<td align="center"><b>Thread B</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>The sequence point at a call to a library thread-creation
|
||||
function.</td>
|
||||
|
||||
<td>The first sequence point of the initial function in the new
|
||||
thread created by the Thread A call.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>The sequence point at a call to a library function which
|
||||
locks a mutex, directly or by waiting for a condition
|
||||
variable.</td>
|
||||
|
||||
<td>The sequence point after a call to a library function which
|
||||
unlocks the same mutex.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>The last sequence point before thread termination.</td>
|
||||
|
||||
<td>The sequence point after a call to a library function which
|
||||
joins the terminated thread.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>The sequence point at a call to a library function which
|
||||
signals or broadcasts a condition variable.</td>
|
||||
|
||||
<td>The sequence point after the call to the library function
|
||||
which was waiting on that same condition variable or
|
||||
signal.</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<p>The architecture of the execution environment and the observable
|
||||
behavior of the abstract machine [1.9] shall be the same on all
|
||||
processors.</p>
|
||||
|
||||
<p>The latitude granted by the C++ standard for an implementation to
|
||||
alter the definition of observable behavior of the abstract machine to
|
||||
include additional library I/O functions [1.9/6] is extended to include
|
||||
threading library functions.</p>
|
||||
|
||||
<p>When an exception is thrown and there is no matching exception
|
||||
handler in the same thread, behavior is undefined. The preferred
|
||||
behavior is the same as when there is no matching exception handler in
|
||||
a program [15.3/9]. That is, terminate() is called, and it is
|
||||
implementation defined whether or not the stack is unwound.</p>
|
||||
|
||||
<h2><a name="Acknowledgements">Acknowledgements</a></h2>
|
||||
|
||||
<p>This document has been much improved by the incorporation of
|
||||
comments from William Kempf.</p>
|
||||
|
||||
<p>The visibility rules are based on <a href=
|
||||
"bibliography.html#Butenhof-97">[Butenhof 97]</a>.</p>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->06 October, 2002<!--webbot bot="Timestamp" endspan i-checksum="38429" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.<br>
|
||||
</i>© Copyright Beman Dawes, 2001</p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %b %Y" startspan -->05 Nov 2001<!--webbot bot="Timestamp" endspan i-checksum="15246" --></p>
|
||||
|
||||
<p>© Copyright Beman Dawes, 2001</p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
@@ -1,110 +0,0 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Header <boost/thread/exceptions.hpp></title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Header <<a href="../../../boost/thread/exceptions.hpp">boost/thread/exceptions.hpp</a>></h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<h2>Contents</h2>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#classes">Classes</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-lock_error">Class <code>lock_error</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-lock_error-synopsis">Class <code>lock_error</code> synopsis</a></dt>
|
||||
<dt><a href="#class-lock_error-ctors">Class <code>lock_error</code> constructors
|
||||
and destructor</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#class-thread_resource_error">Class <code>thread_resource_error</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-thread_resource_error-synopsis">Class <code>thread_resource_error</code>
|
||||
synopsis</a></dt>
|
||||
<dt><a href="#class-thread_resource_error-ctors">Class <code>thread_resource_error</code>
|
||||
constructors and destructor</a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
</dl>
|
||||
<hr>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>Include the header <<a href="../../../boost/thread/exceptions.hpp">boost/thread/exceptions.hpp</a>>
|
||||
to define the exception types that may be thrown by <b>Boost.Threads</b> classes.</p>
|
||||
<h2><a name="classes"></a>Classes</h2>
|
||||
<h3><a name="class-lock_error"></a>Class <code>lock_error</code></h3>
|
||||
<p>The lock_error class defines an exception type thrown to indicate a locking
|
||||
related error has been detected. Examples of such errors include a lock operation
|
||||
which can be determined to result in a deadlock, or unlock operations attempted
|
||||
by a thread that does not own the lock. </p>
|
||||
<h4><a name="class-lock_error-synopsis"></a>Class <code>lock_error</code> synopsis</h4>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
class lock_error : public std::logical_error
|
||||
{
|
||||
public:
|
||||
lock_error();
|
||||
};
|
||||
};
|
||||
</pre>
|
||||
<h4><a name="class-lock_error-ctors"></a>Class <code>lock_error</code> constructors
|
||||
and destructor</h4>
|
||||
<pre>
|
||||
lock_error();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Constructs a <code>lock_error</code> object.</dt>
|
||||
</dl>
|
||||
<h3><a name="class-thread_resource_error"></a>Class <code>thread_resource_error</code></h3>
|
||||
<p>The thread_resource_error class defines an exception type that is thrown by
|
||||
constructors in the Boost.Threads library when thread related resources can
|
||||
not be acquired. This does not include memory allocation failures which instead
|
||||
throw std::bad_alloc. </p>
|
||||
<h4><a name="class-thread_resource_error-synopsis"></a>Class <code>thread_resource_error</code>
|
||||
synopsis</h4>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
class thread_resource_error : public std::runtime_error
|
||||
{
|
||||
public:
|
||||
thread_resource_error();
|
||||
};
|
||||
};
|
||||
</pre>
|
||||
<h4><a name="class-thread_resource_error-ctors"></a>Class <code>thread_resource_error</code>
|
||||
constructors and destructor</h4>
|
||||
<pre>
|
||||
thread_resource_error();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Constructs a <code>thread_resource_error</code> object.</dt>
|
||||
</dl>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
291
doc/faq.html
291
doc/faq.html
@@ -1,92 +1,97 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - FAQ</title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Frequently Asked Questions (FAQs)</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#question1">1. Are lock objects thread safe?</a></dt>
|
||||
<dt><a href="#question2a">2a. Why was <b>Boost.Threads</b> modeled after (specific
|
||||
library name)?</a></dt>
|
||||
<dt><a href="#question2b">2b. Why wasn't <b>Boost.Threads</b> modeled after
|
||||
(specific library name)?</a></dt>
|
||||
<dt><a href="#question3">3. Why do mutexes have noncopyable semantics?</a></dt>
|
||||
<dt><a href="#question4">4. How can you prevent deadlock from occurring when
|
||||
a thread must lock multiple mutexes?</a></dt>
|
||||
<dt><a href="#question5">5. Don't noncopyable mutex semantics mean that a class
|
||||
with a mutex member will be noncopyable as well?</a></dt>
|
||||
<dt><a href="#question6">6. How can you lock a mutex member in a const member
|
||||
function (in order to implement the monitor pattern)?</a></dt>
|
||||
<dt><a href="#question7">7. Why supply condition variables rather than event
|
||||
variables?</a></dt>
|
||||
<dt><a href="#question8">8. Why isn't thread cancellation or termination provided?</a></dt>
|
||||
<dt><a href="#question9">9. Is it safe for threads to share automatic storage
|
||||
duration (stack) objects via pointers or references?</a></dt>
|
||||
<dt><a href="#question10">10. Why has class semaphore disappeared?</a></dt>
|
||||
</dl>
|
||||
<h2><a name="question1"></a>1. Are lock objects <a href="definitions.html#definition-thread-safe">
|
||||
thread safe</a>?</h2>
|
||||
<p><b>No!</b> Lock objects are not meant to be shared between threads. They are
|
||||
meant to be short-lived objects created on automatic storage within a code block.
|
||||
Any other usage is just likely to lead to errors and won't really be of
|
||||
actual benefit any way. Share <a href=
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, FAQ</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width="277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">Frequently Asked Questions</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<h2>1. Are lock objects <a href="definitions.html#Thread-safe">
|
||||
thread-safe</a>?</h2>
|
||||
|
||||
<p><b>No!</b> Lock objects are not meant to be shared between threads.
|
||||
They are meant to be short lived objects created on automatic storage
|
||||
within a code block. Any other usage is just likely to lead to errors
|
||||
and won't really be of actual benefit any way. Share <a href=
|
||||
"mutex_concept.html">mutexes</a>, not locks. For more information see
|
||||
the <a href="rationale.html#lock_objects">rationale</a> behind the design for
|
||||
lock objects.</p>
|
||||
<h2><a name="question2a"></a>2a. Why was <b>Boost.Threads</b> modeled after (specific
|
||||
library name)?</h2>
|
||||
<p>It wasn't. Boost.Threads was designed from scratch. Extensive design discussions
|
||||
involved numerous people representing a wide range of experience across many
|
||||
platforms. To ensure portability, the initial implements were done in parallel
|
||||
using POSIX Threads and the Win32 threading API. But the Boost.Threads design
|
||||
is very much in the spirit of C++, and thus doesn't model such C based APIs.</p>
|
||||
<h2><a name="question2b"></a>2b. Why wasn't Boost.Threads modeled after (specific
|
||||
library name)?</h2>
|
||||
<p>Existing C++ libraries either seemed dangerous (often failing to take advantage
|
||||
of prior art to reduce errors) or had excessive dependencies on library components
|
||||
unrelated to threading. Existing C libraries couldn't meet our C++ requirements,
|
||||
and were also missing certain features. For instance, the WIN32 thread API lacks
|
||||
condition variables, even though these are critical for the important Monitor
|
||||
pattern <a href="bibliography.html#Schmidt-00">[Schmidt 00]</a>.</p>
|
||||
<h2><a name="question3"></a>3. Why do <a href="mutex_concept.html">Mutexes</a>
|
||||
have noncopyable semantics?</h2>
|
||||
<p>To ensure that <a href="definitions.html#Deadlock">deadlocks</a> don't
|
||||
occur. The only logical form of copy would be to use some sort of shallow copy
|
||||
semantics in which multiple mutex objects could refer to the same mutex state.
|
||||
This means that if ObjA has a mutex object as part of its state and ObjB is
|
||||
copy constructed from it, then when ObjB::foo() locks the mutex it has effectively
|
||||
locked ObjA as well. This behavior can result in deadlock. Other copy semantics
|
||||
result in similar problems (if you think you can prove this to be wrong then
|
||||
supply us with an alternative and we'll reconsider).</p>
|
||||
<h2><a name="question4"></a>4. How can you prevent <a href="definitions.html#Deadlock">
|
||||
deadlock</a> from occurring when a thread must lock multiple mutexes?</h2>
|
||||
<p>Always lock them in the same order. One easy way of doing this is to use each
|
||||
mutex's address to determine the order in which they are locked. A future
|
||||
Boost.Threads concept may wrap this pattern up in a reusable class.</p>
|
||||
<h2><a name="question5"></a>5. Don't noncopyable <a href="mutex_concept.html">mutex</a>
|
||||
semantics mean that a class with a mutex member will be noncopyable as well?</h2>
|
||||
<p>No, but what it does mean is that the compiler can't generate a copy constructor
|
||||
and assignment operator, so they will have to be coded explicitly. This is a
|
||||
<b>good thing</b>, however, since the compiler generated operations would not
|
||||
be <a href=
|
||||
"definitions.html#Thread-safe">thread-safe</a>. The following is a simple
|
||||
example of a class with copyable semantics and internal synchronization through
|
||||
a mutex member.</p>
|
||||
<pre>class counter
|
||||
the <a href="rationale.html#lock_objects">rationale</a> behind the
|
||||
design for lock objects.</p>
|
||||
|
||||
<h2>2a. Why was Boost.Threads modeled after (specific library
|
||||
name)?</h2>
|
||||
|
||||
<p>It wasn't. Boost.Threads was designed from scratch. Extensive
|
||||
design discussions involved numerous people representing a wide range
|
||||
of experience across many platforms. To ensure portability, the initial
|
||||
implements were done in parallel using POSIX Threads and theWin32
|
||||
threading API. But the Boost.Threads design is very much in the spirit
|
||||
of C++, and thus doesn't model such C based APIs.</p>
|
||||
|
||||
<h2>2b. Why wasn't Boost.Threads modeled after (specific library
|
||||
name)?</h2>
|
||||
|
||||
<p>Existing C++ libraries either seemed dangerous (often failing to
|
||||
take advantage of prior art to reduce errors) or had excessive
|
||||
dependencies on library components unrelated to threading. Existing C
|
||||
libraries couldn't meet our C++ requirements, and were also missing
|
||||
certain features. For instance, the WIN32 thread API lacks condition
|
||||
variables, even though these are critical for the important Monitor
|
||||
pattern <a href="bibliography.html#Schmidt-00">[Schmidt 00]</a>.</p>
|
||||
|
||||
<h2>3. Why do <a href="mutex_concept.html">Mutexes</a> have noncopyable
|
||||
semantics?</h2>
|
||||
|
||||
<p>To ensure that <a href="definitions.html#Deadlock">deadlocks</a>
|
||||
don't occur. The only logical form of copy would be to use some
|
||||
sort of shallow copy semantics in which multiple mutex objects could
|
||||
refer to the same mutex state. This means that if ObjA has a mutex
|
||||
object as part of its state and ObjB is copy constructed from it, then
|
||||
when ObjB::foo() locks the mutex it has effectively locked ObjA as
|
||||
well. This behavior can result in deadlock. Other copy semantics result
|
||||
in similar problems (if you think you can prove this to be wrong then
|
||||
supply us with an alternative and we'll reconsider).</p>
|
||||
|
||||
<h2>4. How can you prevent <a href="definitions.html#Deadlock">
|
||||
deadlock</a> from occurring when a thread must lock multiple
|
||||
mutexes?</h2>
|
||||
|
||||
<p>Always lock them in the same order. One easy way of doing this is to
|
||||
use each mutex's address to determine the order in which they are
|
||||
locked. A future Boost.Threads concept may wrap this pattern up in a
|
||||
reusable class.</p>
|
||||
|
||||
<h2>5. Don't noncopyable <a href="mutex_concept.html">mutex</a>
|
||||
semantics mean that a class with a mutex member will be noncopyable as
|
||||
well?</h2>
|
||||
|
||||
<p>No, but what it does mean is that the compiler can't generate a
|
||||
copy constructor and assignment operator, so they will have to be coded
|
||||
explicitly. This is a <b>good thing</b>, however, since the compiler
|
||||
generated operations would not be <a href=
|
||||
"definitions.html#Thread-safe">thread-safe</a>. The following is a
|
||||
simple example of a class with copyable semantics and internal
|
||||
synchronization through a mutex member.</p>
|
||||
<pre>
|
||||
class counter
|
||||
{
|
||||
public:
|
||||
// Doesn't need synchronization since there can be no references to *this
|
||||
@@ -95,28 +100,28 @@ public:
|
||||
: m_value(initial_value)
|
||||
{
|
||||
}
|
||||
|
||||
// We only need to synchronize other for the same reason we don't have to
|
||||
|
||||
// We only need to syncronize other for the same reason we don't have to
|
||||
// synchronize on construction!
|
||||
counter(const counter& other)
|
||||
{
|
||||
boost::mutex::scoped_lock scoped_lock(other.m_mutex);
|
||||
m_value = other.m_value;
|
||||
}
|
||||
|
||||
|
||||
// For assignment we need to synchronize both objects!
|
||||
const counter& operator=(const counter& other)
|
||||
{
|
||||
if (this == &other)
|
||||
return *this;
|
||||
|
||||
|
||||
boost::mutex::scoped_lock lock1(&m_mutex < &other.m_mutex ? m_mutex : other.m_mutex);
|
||||
boost::mutex::scoped_lock lock2(&m_mutex > &other.m_mutex ? m_mutex : other.m_mutex);
|
||||
m_value = other.m_value;
|
||||
|
||||
|
||||
return *this;
|
||||
}
|
||||
|
||||
|
||||
int value() const
|
||||
{
|
||||
boost::mutex::scoped_lock scoped_lock(m_mutex);
|
||||
@@ -127,54 +132,62 @@ public:
|
||||
boost::mutex::scoped_lock scoped_lock(m_mutex);
|
||||
return ++m_value;
|
||||
}
|
||||
|
||||
|
||||
private:
|
||||
mutable boost::mutex m_mutex;
|
||||
int m_value;
|
||||
};
|
||||
</pre>
|
||||
<h2><a name="question6"></a>6. How can you lock a <a href="mutex_concept.html">mutex</a>
|
||||
member in a const member function, in order to implement the Monitor Pattern?</h2>
|
||||
<p>The Monitor Pattern mutex <a href="bibliography.html#Schmidt-00"> [Schmidt
|
||||
00]</a> should simply be declared as mutable. See the example code above. The
|
||||
internal state of mutex types could have been made mutable, with all lock calls
|
||||
made via const functions, but this does a poor job of documenting the actual
|
||||
semantics (and in fact would be incorrect since the logical state of a locked
|
||||
mutex clearly differs from the logical state of an unlocked mutex). Declaring
|
||||
a mutex member as mutable clearly documents the intended semantics.</p>
|
||||
<h2><a name="question7"></a>7. Why supply <a href="condition.html">condition variables</a>
|
||||
rather than <a href="rationale.html#Events">event variables</a>?</h2>
|
||||
<p>Condition variables result in user code much less prone to
|
||||
<a href="definitions.html#definition-race-condition">race conditions</a> than event variables.
|
||||
See <a href="rationale.html#Events">Rationale</a> for analysis. Also see <a href="bibliography.html#Hoare-74">[Hoare
|
||||
74]</a> and <a href="bibliography.html#Schmidt-00">[Schmidt 00]</a>.</p>
|
||||
<h2><a name="question8"></a>8. Why isn't thread cancellation or termination
|
||||
provided?</h2>
|
||||
<p>There's a valid need for thread termination, so at some point Boost.Threads
|
||||
probably will include it, but only after we can find a truly safe (and portable)
|
||||
mechanism for this concept.</p>
|
||||
<h2><a name="question9"></a>9. Is it safe for threads to share automatic storage
|
||||
duration (stack) objects via pointers or references?</h2>
|
||||
<p>Only if you can guarantee that the lifetime of the stack object will not end
|
||||
while other threads might still access the object. Thus the safest practice
|
||||
is to avoid sharing stack objects, particularly in designs where threads are
|
||||
created and destroyed dynamically. Restrict sharing of stack objects to simple
|
||||
designs with very clear and unchanging function and thread lifetimes. (Suggested
|
||||
by Darryl Green).</p>
|
||||
<h2><a name="question10"></a>10. Why has class semaphore disappeared?</h2>
|
||||
<p>Semaphore was removed as too error prone. The same effect can be achieved with
|
||||
greater safety by the combination of a mutex and a condition variable.</p>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->09 January, 2003<!--webbot bot="Timestamp" endspan i-checksum="38582" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
<h2>6. How can you lock a <a href="mutex_concept.html">mutex</a> member
|
||||
in a const member function, in order to implement the Monitor
|
||||
Pattern?</h2>
|
||||
|
||||
<p>The Monitor Pattern mutex <a href="bibliography.html#Schmidt-00">
|
||||
[Schmidt 00]</a> should simply be declared as mutable. See the example
|
||||
code above. The internal state of mutex types could have been made
|
||||
mutable, with all lock calls made via const functions, but this does a
|
||||
poor job of documenting the actual semantics. Declaring a mutex member
|
||||
as mutable clearly documentations the intended semantics.</p>
|
||||
|
||||
<h2>7. Why supply <a href="condition.html">condition variables</a>
|
||||
rather than <a href="rationale.html#Events">event variables</a>?</h2>
|
||||
|
||||
<p>Condition variables result in user code much less prone to <a href=
|
||||
"definitions.html#Race condition">race conditions</a> than event
|
||||
variables. See <a href="rationale.html#Events">Rationale</a> for
|
||||
analysis. Also see <a href="bibliography.html#Hoare-74">[Hoare74]</a>
|
||||
and <a href="bibliography.html#Schmidt-00">[Schmidt 00]</a>.</p>
|
||||
|
||||
<h2>8. Why isn't thread cancellation or termination provided?</h2>
|
||||
|
||||
<p>There's a valid need for thread termination, so at some point
|
||||
Boost.Threads probably will include it, but only after we can find a
|
||||
truly safe (and portable) mechanism for this concept.</p>
|
||||
|
||||
<h2>9. Is it safe for threads to share automatic storage duration
|
||||
(stack) objects via pointers or references?</h2>
|
||||
|
||||
<p>Only if you can guarantee that the lifetime of the stack object will
|
||||
not end while other threads might still access the object. Thus the
|
||||
safest practice is to avoid sharing stack objects, particularly in
|
||||
designs where threads are created and destroyed dynamically. Restrict
|
||||
sharing of stack objects to simple designs with very clear and
|
||||
unchanging function and thread lifetimes. (Suggested by Darryl
|
||||
Green).</p>
|
||||
|
||||
<h2>10. Why has class semaphore disappeared?</h2>
|
||||
|
||||
<p>Semaphore was removed as too error prone. The same effect can be
|
||||
achieved with greater safety by the combination of a mutex and a
|
||||
condition variable.</p>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
290
doc/index.html
290
doc/index.html
@@ -1,156 +1,138 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads</title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Index</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<h2>Contents</h2>
|
||||
<dl class="index">
|
||||
<dt><a href="overview.html">Overview</a></dt>
|
||||
<dt><a href="mutex_concept.html">Mutex Concepts</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="mutex_concept.html#Mutex">Mutex</a></dt>
|
||||
<dt><a href="mutex_concept.html#TryMutex">TryMutex</a></dt>
|
||||
<dt><a href="mutex_concept.html#TimedMutex">TimedMutex</a></dt>
|
||||
</dl>
|
||||
<dt><a href="lock_concept.html">Lock Concepts</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="lock_concept.html#Lock">Lock</a></dt>
|
||||
<dt><a href="lock_concept.html#ScopedLock">ScopedLock</a></dt>
|
||||
<dt><a href="lock_concept.html#ScopedTryLock">ScopedTryLock</a></dt>
|
||||
<dt><a href="lock_concept.html#ScopedTimedLock">ScopedTimedLock</a></dt>
|
||||
</dl>
|
||||
<dt>Reference</dt>
|
||||
<dl class="index">
|
||||
<dt><a href="condition.html"><code><boost/thread/condition.hpp></code></a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="condition.html#classes">Classes</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="condition.html#class-condition"><code>condition</code></a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
</dl>
|
||||
<dl class="index">
|
||||
<dt><a href="exceptions.html"><code><boost/thread/exceptions.hpp></code></a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="exceptions.html#classes">Classes</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="exceptions.html#class-lock_error"><code>lock_error</code></a></dt>
|
||||
<dt><a href="exceptions.html#class-thread_resource_error"><code>thread_resource_error</code></a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
</dl>
|
||||
<dl class="index">
|
||||
<dt><a href="mutex.html"><code><boost/thread/mutex.hpp></code></a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="mutex.html#classes">Classes</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="mutex.html#class-mutex"><code>mutex</code></a></dt>
|
||||
<dt><a href="mutex.html#class-try_mutex"><code>try_mutex</code></a></dt>
|
||||
<dt><a href="mutex.html#class-timed_mutex"><code>timed_mutex</code></a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
</dl>
|
||||
<dl class="index">
|
||||
<dt><a href="once.html"><code><boost/thread/once.hpp></code></a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="once.html#macros">Macros</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="once.html#macro-BOOST_ONCE_INIT"><code>BOOST_ONCE_INIT</code></a></dt>
|
||||
</dl>
|
||||
<dt><a href="once.html#types">Types</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="once.html#type-once_flag"><code>once_flag</code></a></dt>
|
||||
</dl>
|
||||
<dt><a href="once.html#functions">Functions</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="once.html#function-call_once"><code>call_once</code></a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
</dl>
|
||||
<dl class="index">
|
||||
<dt><a href="recursive_mutex.html"><code><boost/thread/recursive_mutex.hpp></code></a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="recursive_mutex.html#classes">Classes</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="recursive_mutex.html#class-recursive_mutex"><code>recursive_mutex</code></a></dt>
|
||||
<dt><a href="recursive_mutex.html#class-recursive_try_mutex"><code>recursive_try_mutex</code></a></dt>
|
||||
<dt><a href="recursive_mutex.html#class-recursive_timed_mutex"><code>recursive_timed_mutex</code></a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
</dl>
|
||||
<dl class="index">
|
||||
<dt><a href="thread.html"><code><boost/thread/thread.hpp></code></a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="thread.html#classes">Classes</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="thread.html#class-thread"><code>thread</code></a></dt>
|
||||
<dt><a href="thread.html#class-thread_group"><code>thread_group</code></a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
</dl>
|
||||
<dl class="index">
|
||||
<dt><a href="tss.html"><code><boost/thread/tss.hpp></code></a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="tss.html#classes">Classes</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="tss.html#class-thread_specific_ptr"><code>thread_specific_ptr</code></a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
</dl>
|
||||
<dl class="index">
|
||||
<dt><a href="xtime.html"><code><boost/thread/xtime.hpp></code></a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="xtime.html#values">Values</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="xtime.html#value-spec"><code>TIME_UTC</code></a></dt>
|
||||
</dl>
|
||||
<dt><a href="xtime.html#classes">Classes</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="xtime.html#class-xtime"><code>xtime</code></a></dt>
|
||||
</dl>
|
||||
<dt><a href="xtime.html#functions">Functions</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="xtime.html#function-xtime_get"><code>xtime_get</code></a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
</dl>
|
||||
<dt><a href="configuration.html">Configuration Information</a></dt>
|
||||
<dt><a href="build.html">Building and Testing</a></dt>
|
||||
<dt><a href="introduction.html">Introduction to Design</a></dt>
|
||||
<dt><a href="rationale.html">Rationale</a></dt>
|
||||
<dt><a href="definitions.html">Definitions</a></dt>
|
||||
<dt><a href="faq.html">Frequently Asked Questions (FAQs)</a></dt>
|
||||
<dt><a href="bibliography.html">Bibliography</a></dt>
|
||||
<dt><a href="acknowledgments.html">Acknowledgments</a></dt>
|
||||
</dl>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
|
||||
<title>Boost.Threads, Index</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">Documentation Map</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<h2>Contents</h2>
|
||||
|
||||
<ul>
|
||||
<li><a href="overview.html">Overview</a></li>
|
||||
|
||||
<li>
|
||||
<a href="mutex_concept.html">Mutex Concepts</a>
|
||||
|
||||
<ul>
|
||||
<li><a href="mutex_concept.html#Mutex">Mutex</a></li>
|
||||
|
||||
<li><a href="mutex_concept.html#TryMutex">TryMutex</a></li>
|
||||
|
||||
<li><a href="mutex_concept.html#TimedMutex">
|
||||
TimedMutex</a></li>
|
||||
</ul>
|
||||
</li>
|
||||
|
||||
<li>
|
||||
Mutex Classes
|
||||
|
||||
<ul>
|
||||
<li><a href="mutex.html">mutex / try_mutex /
|
||||
timed_mutex</a></li>
|
||||
|
||||
<li><a href="recursive_mutex.html">recursive_mutex /
|
||||
recursive_try_mutex / recursive_timed_mutex</a></li>
|
||||
</ul>
|
||||
</li>
|
||||
|
||||
<li>
|
||||
<a href="lock_concept.html">Lock Concepts</a>
|
||||
|
||||
<ul>
|
||||
<li><a href="lock_concept.html#Lock">Lock</a></li>
|
||||
|
||||
<li><a href="lock_concept.html#ScopedLock">
|
||||
ScopedLock</a></li>
|
||||
|
||||
<li><a href="lock_concept.html#ScopedTryLock">
|
||||
ScopedTryLock</a></li>
|
||||
|
||||
<li><a href="lock_concept.html#ScopedTimedLock">
|
||||
ScopedTimedLock</a></li>
|
||||
</ul>
|
||||
</li>
|
||||
|
||||
<li>
|
||||
Lock Classes
|
||||
|
||||
<ul>
|
||||
<li><a href="scoped_lock.html">scoped_lock</a></li>
|
||||
|
||||
<li><a href="scoped_try_lock.html">scoped_try_lock</a></li>
|
||||
|
||||
<li><a href="scoped_timed_lock.html">
|
||||
scoped_timed_lock</a></li>
|
||||
</ul>
|
||||
</li>
|
||||
|
||||
<li>Class <a href="condition.html">condition</a></li>
|
||||
|
||||
<li>Class <a href="thread_specific_ptr.html">
|
||||
thread_specific_ptr</a></li>
|
||||
|
||||
<li>Class <a href="thread.html">thread</a></li>
|
||||
|
||||
<li>Class <a href="thread_group.html">thread_group</a></li>
|
||||
|
||||
<li>Class <a href="xtime.html">xtime</a></li>
|
||||
|
||||
<li>Class <a href="lock_error.html">lock_error</a></li>
|
||||
|
||||
<li>Class <a href="thread_resource_error.html">
|
||||
thread_resource_error</a></li>
|
||||
|
||||
<li>Routine <a href="call_once.html">call_once</a></li>
|
||||
|
||||
<li><a href="config.html">Configuration Information</a></li>
|
||||
|
||||
<li><a href="introduction.html">Introduction to design</a></li>
|
||||
|
||||
<li><a href="rationale.html">Rationale for design
|
||||
decisions</a></li>
|
||||
|
||||
<li><a href="definitions.html">Definitions</a></li>
|
||||
|
||||
<li><a href="faq.html">Frequently Asked Questions</a></li>
|
||||
|
||||
<li><a href="bibliography.html">Bibliography</a></li>
|
||||
|
||||
<li><a href="acknowledgements.html">Acknowledgements</a></li>
|
||||
</ul>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p>© <i>Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001</i></p>
|
||||
|
||||
<p>Permission to use, copy, modify, distribute and sell this software
|
||||
and its documentation for any purpose is hereby granted without fee,
|
||||
provided that the above copyright notice appear in all copies and that
|
||||
both that copyright notice and this permission notice appear in
|
||||
supporting documentation. William E. Kempf makes no representations
|
||||
about the suitability of this software for any purpose. It is provided
|
||||
"as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
@@ -1,159 +1,194 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Introduction to Design</title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Introduction to Design</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#motivation">Motivation</a></dt>
|
||||
<dt><a href="#goals">Goals</a></dt>
|
||||
<dt><a href="#phases">Iterative Phases</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#phase1">Phase 1, Synchronization Primitives</a></dt>
|
||||
<dt><a href="#phase2">Phase 2, Thread Management and Thread Specific Storage</a></dt>
|
||||
<dt><a href="#next-phase">The Next Phase</a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
<h2><a name="motivation"></a>Motivation</h2>
|
||||
<p>With client/server and three-tier architectures becoming common place in today's
|
||||
world, it's becoming increasingly important for programs to be able to handle
|
||||
parallel processing. Modern day operating systems usually provide some support
|
||||
for this through native thread APIs. Unfortunately, writing portable code that
|
||||
makes use of parallel processing in C++ is made very difficult by a lack of
|
||||
a standard interface for these native APIs. Further, these APIs are almost universally
|
||||
C APIs and fail to take advantage of C++'s strengths, or to address C++'s
|
||||
issues.</p>
|
||||
<p>The <b>Boost.Threads</b> library is an attempt to define a portable interface
|
||||
for writing parallel processes in C++.</p>
|
||||
<h2><a name="goals"></a>Goals</h2>
|
||||
<p>The <b>Boost.Threads</b> library has several goals that should help to set
|
||||
it apart from other solutions. These goals are listed in order of precedence
|
||||
with full descriptions below.</p>
|
||||
<ul>
|
||||
<li> <b>Portability</b>
|
||||
<p><b>Boost.Threads</b> was designed to be highly portable. The goal is for
|
||||
the interface to be easily implemented on any platform that supports threads,
|
||||
and possibly even on platforms without native thread support.</p>
|
||||
</li>
|
||||
<li> <b>Safety</b>
|
||||
<p><b>Boost.Threads</b> was designed to be as safe as possible. Writing <a href="definitions.html#Thread-safe">thread-safe</a>
|
||||
code is very difficult and successful libraries must strive to insulate
|
||||
the programmer from dangerous constructs as much as possible. This is accomplished
|
||||
in several ways:</p>
|
||||
<ul>
|
||||
<li>
|
||||
<p align="left">C++ language features are used make correct usage easy
|
||||
(if possible, the default) and error-prone impossible or at least more
|
||||
difficult. For example, see the <a href="mutex_concept.html">Mutex</a>
|
||||
and <a href="lock_concept.html">Lock</a> designs, and how note how they
|
||||
interact.</p>
|
||||
</li>
|
||||
<li>
|
||||
<p align="left">Certain traditional concurrent programming features are
|
||||
considered so error-prone that they are not provided at all. For example,
|
||||
see the <a
|
||||
href="rationale.html#Events">Events Not Provided</a> rationale.</p>
|
||||
</li>
|
||||
<li>
|
||||
<p align="left">Dangerous features, or features which may be misused,
|
||||
are identified as such in the documentation to make users aware of potential
|
||||
pitfalls.</p>
|
||||
</li>
|
||||
</ul>
|
||||
</li>
|
||||
<li> <b>Flexibility</b>
|
||||
<p><b>Boost.Threads</b> was designed to be flexible. This goal is often at
|
||||
odds with <i>safety</i>. When functionality might be compromised by the
|
||||
desire to keep the interface safe, <b> Boost.Threads</b> has been designed
|
||||
to provide the functionality, but to make it's use prohibitive for general
|
||||
use. In other words, the interfaces have been designed such that it's usually
|
||||
obvious when something is unsafe, and the documentation is written to explain
|
||||
why.</p>
|
||||
</li>
|
||||
<li> <b>Efficiency</b>
|
||||
<p><b>Boost.Threads</b> was designed to be as efficient as possible. When
|
||||
building a library on top of another library there is always a danger that
|
||||
the result will be so much slower than the "native" API that programmers
|
||||
are inclined to ignore the higher level API. <b>Boost.Threads</b> was designed
|
||||
to minimize the chances of this occurring. The interfaces have been crafted
|
||||
to allow an implementation the greatest chance of being as efficient as
|
||||
possible. This goal is often at odds with the goal for <i>safety</i>. Every
|
||||
effort was made to ensure efficient implementations, but when in conflict
|
||||
<i>safety</i> has always taken precedence.</p>
|
||||
</li>
|
||||
</ul>
|
||||
<h2><a name="phases"></a>Iterative Phases</h2>
|
||||
<p>Another goal of <b>Boost.Threads</b> was to take a dynamic, iterative approach
|
||||
in its development. The computing industry is still exploring the concepts of
|
||||
parallel programming. Most thread libraries supply only simple primitive concepts
|
||||
for thread synchronization. These concepts are very simple, but they are very
|
||||
difficult to use safely or to provide formal proofs for constructs built on
|
||||
top of them. There has been a lot of research in other concepts, such as in
|
||||
"Communicating Sequential Processes." <b>Boost.Threads</b> was designed
|
||||
in iterative steps, providing the building blocks necessary for the next step,
|
||||
and giving the researcher the tools necessary to explore new concepts in a portable
|
||||
manner.</p>
|
||||
<p>Given the goal of following a dynamic, iterative approach <b> Boost.Threads</b>
|
||||
shall go through several growth cycles. Each phase in its development shall
|
||||
be roughly documented here.</p>
|
||||
<h3><a name="phase1"></a>Phase 1, Synchronization Primitives</h3>
|
||||
<p>Boost is all about providing high quality libraries with implementations for
|
||||
many platforms. Unfortunately, there's a big problem faced by developers
|
||||
wishing to supply such high quality libraries, namely thread-safety. The C++
|
||||
standard doesn't address threads at all, but real world programs often make
|
||||
use of native threading support. A portable library that doesn't address
|
||||
the issue of thread-safety is there for not much help to a programmer who wants
|
||||
to use the library in his multithreaded application. So there's a very great
|
||||
need for portable primitives that will allow the library developer to create
|
||||
<a href="definitions.html#Thread-safe"> thread-safe</a> implementations. This
|
||||
need far out weighs the need for portable methods to create and manage threads.</p>
|
||||
<p>Because of this need, the first phase of <b>Boost.Threads</b> focuses solely
|
||||
on providing portable primitive concepts for thread synchronization. Types provided
|
||||
in this phase include the <a href="mutex.html"> mutex/try_mutex/timed_mutex</a>,
|
||||
<a href="recursive_mutex.html"> recursive_mutex/recursive_try_mutex/recursive_timed_mutex</a>
|
||||
and <a href="exceptions.html#class-lock_error">lock_error</a>. These are considered
|
||||
the "core" synchronization primitives, though there are others that
|
||||
will be added in later phases.</p>
|
||||
<h3><a name="phase2"></a>Phase 2, Thread Management and Thread Specific Storage</h3>
|
||||
<p>This phase addresses the creation and management of threads and provides a
|
||||
mechanism for thread specific storage (data associated with a thread instance).
|
||||
Thread management is a tricky issue in C++, so this phase addresses only the
|
||||
basic needs of multithreaded program. Later phases are likely to add additional
|
||||
functionality in this area. This phase of <b>Boost.Threads</b> adds the <a href="thread.html">thread</a>
|
||||
and <a href="tss.html#class-thread_specific_ptr">thread_specific_ptr</a> types.
|
||||
With these additions the <b>Boost.Threads</b> library can be considered minimal
|
||||
but complete.</p>
|
||||
<h3><a name="next-phase"></a>The Next Phase</h3>
|
||||
<p>The next phase will address more advanced synchronization concepts, such as
|
||||
read/write mutexes and barriers.</p>
|
||||
<hr>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
|
||||
<title>Boost.Threads, Introduction</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#ffffff" link="#0000ff" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img height="86" alt="C++ Boost" src=
|
||||
"../../../c++boost.gif" width="277"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">Introduction</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<h3>Motivation</h3>
|
||||
|
||||
<p>With client/server and three-tier architectures becoming common
|
||||
place in today's world, it's becoming increasingly important
|
||||
for programs to be able to handle parallel processing. Modern day
|
||||
operating systems usually provide some support for this through native
|
||||
thread APIs. Unfortunately, writing portable code that makes use of
|
||||
parallel processing in C++ is made very difficult by a lack of a
|
||||
standard interface for these native APIs. Further, these APIs are
|
||||
almost universally C APIs and fail to take advantage of C++'s
|
||||
strengths, or to address C++'s issues.</p>
|
||||
|
||||
<p>The <b>Boost.Threads</b> library is an attempt to define a portable
|
||||
interface for writing parallel processes in C++.</p>
|
||||
|
||||
<h3>Goals</h3>
|
||||
|
||||
<p>The <b>Boost.Threads</b> library has several goals that should help
|
||||
to set it apart from other solutions. These goals are listed in order
|
||||
of precedence with full descriptions below.</p>
|
||||
|
||||
<ul>
|
||||
<li>
|
||||
<b>Portability</b>
|
||||
|
||||
<p><b>Boost.Threads</b> was designed to be highly portable. The
|
||||
goal is for the interface to be easily implemented on any
|
||||
platform that supports threads, and possibly even on platforms
|
||||
without native thread support.</p>
|
||||
</li>
|
||||
|
||||
<li>
|
||||
<b>Safety</b>
|
||||
|
||||
<p><b>Boost.Threads</b> was designed to be as safe as possible.
|
||||
Writing <a href="definitions.html#Thread-safe">thread-safe</a>
|
||||
code is very difficult and successful libraries must strive to
|
||||
insulate the programmer from dangerous constructs as much as
|
||||
possible. This is accomplished in several ways:</p>
|
||||
|
||||
<ul>
|
||||
<li>
|
||||
<p align="left">C++ language features are used make
|
||||
correct usage easy (if possible, the default) and
|
||||
error-prone impossible or at least more difficult. For
|
||||
example, see the <a href="mutex_concept.html">Mutex</a>
|
||||
and <a href="lock_concept.html">Lock</a> designs, and
|
||||
how note how they interact.</p>
|
||||
</li>
|
||||
|
||||
<li>
|
||||
<p align="left">Certain traditional concurrent
|
||||
programming features are considered so error-prone that
|
||||
they are not provided at all. For example, see the <a
|
||||
href="rationale.html#Events">Events Not Provided</a>
|
||||
rationale.</p>
|
||||
</li>
|
||||
|
||||
<li>
|
||||
<p align="left">Dangerous features, or features which
|
||||
may be misused, are identified as such in the
|
||||
documentation to make users aware of potential
|
||||
pitfalls.</p>
|
||||
</li>
|
||||
</ul>
|
||||
</li>
|
||||
|
||||
<li>
|
||||
<b>Flexibility</b>
|
||||
|
||||
<p><b>Boost.Threads</b> was designed to be flexible. This goal
|
||||
is often at odds with <i>safety</i>. When functionality might
|
||||
be compromised by the desire to keep the interface safe, <b>
|
||||
Boost.Threads</b> has been designed to provide the
|
||||
functionality, but to make it's use prohibitive for general
|
||||
use.</p>
|
||||
</li>
|
||||
|
||||
<li>
|
||||
<b>Efficiency</b>
|
||||
|
||||
<p><b>Boost.Threads</b> was designed to be as efficient as
|
||||
possible. When building a library on top of another library
|
||||
there is always a danger that the result will be so much slower
|
||||
than the "native" API that programmers are inclined
|
||||
to ignore the higher level API. <b>Boost.Threads</b> was
|
||||
designed to minimize the chances of this occurring. The
|
||||
interfaces have been crafted to allow an implementation the
|
||||
greatest chance of being as efficient as possible. This goal is
|
||||
often at odds with the goal for <i>safety</i>. Every effort was
|
||||
made to ensure efficient implementations, but when in conflict
|
||||
<i>safety</i> has always taken precedence.</p>
|
||||
</li>
|
||||
</ul>
|
||||
|
||||
<h3>Iterative Phases</h3>
|
||||
|
||||
<p>Another goal of <b>Boost.Threads</b> was to take a dynamic,
|
||||
iterative approach in its development. The computing industry is still
|
||||
exploring the concepts of parallel programming. Most thread libraries
|
||||
supply only simple primitive concepts for thread synchronization. These
|
||||
concepts are very simple, but they are very difficult to use safely or
|
||||
to provide formal proofs for constructs built on top of them. Until
|
||||
recently, these primitives were "state of the art" and the
|
||||
only concepts available to programmers. Recently there has been a lot
|
||||
of research in other concepts, such as in "Communicating
|
||||
Sequential Processes." <b>Boost.Threads</b> was designed in
|
||||
iterative steps, providing the building blocks necessary for the next
|
||||
step, and giving the researcher the tools necessary to explore new
|
||||
concepts in a portable manner.</p>
|
||||
|
||||
<p>Given the goal of following a dynamic, iterative approach <b>
|
||||
Boost.Threads</b> shall go through several growth cycles. Each phase in
|
||||
its development shall be roughly documented here.</p>
|
||||
|
||||
<h4>Phase 1, Synchronization Primitives</h4>
|
||||
|
||||
<p>Boost is all about providing high quality libraries with
|
||||
implementations for many platforms. Unfortunately, there's a big
|
||||
problem faced by developers wishing to supply such high quality
|
||||
libraries, namely thread-safety. The C++ standard doesn't address
|
||||
threads at all, but real world programs often make use of native
|
||||
threading support. A portable library that doesn't address the
|
||||
issue of thread-safety is there for not much help to a programmer who
|
||||
wants to use the library in his multi-threaded application. So
|
||||
there's a very great need for portable primitives that will allow
|
||||
the library developer to create <a href="definitions.html#Thread-safe">
|
||||
thread-safe</a> implementations. This need far out weighs the need for
|
||||
portable methods to create and manage threads.</p>
|
||||
|
||||
<p>Because of this need, the first phase of <b>Boost.Threads</b>
|
||||
focuses solely on providing portable primitive concepts for thread
|
||||
synchronization. Types provided in this phase include the <a href="mutex.html">
|
||||
mutex/try_mutex/timed_mutex</a>, <a href="recursive_mutex.html">
|
||||
recursive_mutex/recursive_try_mutex/recursive_timed_mutex</a>, <a href=
|
||||
"scoped_lock.html">scoped_lock</a>, <a href="scoped_try_lock.html">
|
||||
scoped_try_lock</a>, <a href="scoped_timed_lock.html">
|
||||
scoped_timed_lock</a> and <a href="lock_error.html">lock_error</a>.
|
||||
These are considered the "core" synchronization primitives,
|
||||
though there are others that will be added in later phases.</p>
|
||||
|
||||
<h4>Phase 2, Thread Management and Thread Specific Storage</h4>
|
||||
|
||||
<p>This phase addresses the creation and management of threads and
|
||||
provides a mechanism for thread specific storage (data associated with
|
||||
a thread instance). Thread management is a tricky issue in C++, so this
|
||||
phase addresses only the basic needs of multi-threaded program. Later
|
||||
phases are likely to add additional functionality in this area. This
|
||||
phase of <b>Boost.Threads</b> adds the <a href="thread.html">thread</a>
|
||||
and <a href="thread_specific_ptr.html">thread_specific_ptr</a> types.
|
||||
With these additions the <b>Boost.Threads</b> library can be considered
|
||||
minimal but complete.</p>
|
||||
|
||||
<h4>The Next Phase</h4>
|
||||
|
||||
<p>The next phase will address more advanced synchronization concepts,
|
||||
such as read/write mutexes and barriers.</p>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
@@ -1,194 +1,300 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - ScopedLock Concept</title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">ScopedLock Concept</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#concept-requirements">Concept Requirements</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#Lock-concept">Lock Concept</a></dt>
|
||||
<dt><a href="#ScopedLock-concept">ScopedLock Concept</a></dt>
|
||||
<dt><a href="#ScopedTryLock-concept">ScopedTryLock Concept</a></dt>
|
||||
<dt><a href="#ScopedTimedLock-concept">ScopedTimedLock Concept</a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>A lock object provides a safe means for locking and unlocking a mutex object
|
||||
(an object whose type is a model of <a href="mutex_concept.html">Mutex</a> or
|
||||
one of its refinements). In other words they are an implementation of the <i>Scoped
|
||||
Locking</i> <a href="bibliography.html#Schmidt-00">[Schmidt 00]</a> pattern.
|
||||
The <a href="#ScopedLock-concept">ScopedLock</a> concept, with <a href="#ScopedTryLock-concept">ScopedTryLock</a>
|
||||
and <a href="#ScopedTimedLock-concept">ScopedTimedLock</a> refinements, formalize
|
||||
the requirements.</p>
|
||||
<p>Lock objects are constructed with a reference to a mutex object and typically
|
||||
acquire ownership of the mutex object by setting its state to locked. They also
|
||||
ensure ownership is relinquished in the destructor. Lock objects also expose
|
||||
functions to query the lock status and to manually lock and unlock the mutex
|
||||
object.</p>
|
||||
<p>Lock objects are meant to be short lived, expected to be used at block scope
|
||||
only. The lock objects are not <a href="definitions.html#definition-thread-safe">thread-safe</a>.
|
||||
Lock objects must maintain state to indicate whether or not they've been
|
||||
locked and this state is not protected by any synchronization concepts. For
|
||||
this reason a lock object should never be shared between multiple threads.</p>
|
||||
<h2><a name="concept-requirements"></a>Concept Requirements</h2>
|
||||
<h3><a name="Lock-concept"></a>Lock Concept</h3>
|
||||
<p>For a Lock type <code>L</code> and an object <code>lk</code> and const object
|
||||
<code>clk</code> of that type, the following expressions must be well-formed
|
||||
and have the indicated effects.</p>
|
||||
<table summary="Lock expressions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>(&lk)->~L();</code></td>
|
||||
<td><code>if (locked()) unlock();</code></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>(&clk)->operator const void*()</code></td>
|
||||
<td>Returns type void*, non-zero if if the associated mutex object has been
|
||||
locked by <code>clk</code>, otherwise 0.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>clk.locked()</code></td>
|
||||
<td>Returns a <code>bool</code>, <code>(&clk)->operator const void*()
|
||||
!= 0</code></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>lk.lock()</code></td>
|
||||
<td>Throws <code>lock_error</code> if <code>locked()</code>. If the associated
|
||||
mutex object is already locked by some other thread, places the current
|
||||
thread in the <a href="definitions.html#State">Blocked</a> state until the
|
||||
associated mutex is unlocked, after which the current thread is placed in
|
||||
the <a href="definitions.html#State"> Ready</a> state, eventually to be
|
||||
returned to the <a href="definitions.html#State">Running</a> state. If the
|
||||
associated mutex object is already locked by the same thread the behavior
|
||||
is dependent on the <a href="mutex_concept.html#locking-strategies">locking
|
||||
strategy</a> of the associated mutex object.<br>
|
||||
Postcondition: <code>locked() == true</code></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>lk.unlock()</code></td>
|
||||
<td>If <code>!locked()</code>, throws <code>lock_error</code>, otherwise unlocks
|
||||
the associated mutex.<br>
|
||||
Postcondition: <code>!locked()</code></td>
|
||||
</tr>
|
||||
</table>
|
||||
<h3><a name="ScopedLock-concept"></a>ScopedLock Concept</h3>
|
||||
<p>A ScopedLock is a refinement of <a href="#Lock">Lock</a>. For a ScopedLock
|
||||
type <code>L</code> and an object <code>lk</code> of that type, and an object
|
||||
<code>m</code> of a type meeting the <a href="mutex_concept.html#Mutex-concept">Mutex</a>
|
||||
requirements, and an object <code>b</code> of type <code>bool</code>, the following
|
||||
expressions must be well-formed and have the indicated effects.</p>
|
||||
<table summary="ScopedLock expressions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>L lk(m);</code></td>
|
||||
<td>Constructs an object <code>lk</code>, and associates mutex object <code>m</code>
|
||||
with it, then calls <code>lock()</code></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>L lk(m,b);</code></td>
|
||||
<td>Constructs an object <code>lk</code>, and associates mutex object <code>m</code>
|
||||
with it, then if <code>b</code>, calls <code>lock()</code></td>
|
||||
</tr>
|
||||
</table>
|
||||
<h3><a name="ScopedTryLock-concept"></a>ScopedTryLock Concept</h3>
|
||||
<p>A ScopedTryLock is a refinement of <a href="#Lock-concept">Lock</a>. For a
|
||||
ScopedTryLock type <code>L</code> and an object <code>lk</code> of that type,
|
||||
and an object <code>m</code> of a type meeting the <a href="mutex_concept.html#TryMutex-concept">TryMutex</a>
|
||||
requirements, and an object <code>b</code> of type <code>bool</code>, the following
|
||||
expressions must be well-formed and have the indicated effects.</p>
|
||||
<table summary="ScopedTryLock expressions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>L lk(m);</code></td>
|
||||
<td>Constructs an object <code>lk</code>, and associates mutex object <code>m</code>
|
||||
with it, then calls <code>try_lock()</code></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>L lk(m,b);</code></td>
|
||||
<td>Constructs an object <code>lk</code>, and associates mutex object <code>m</code>
|
||||
with it, then if <code>b</code>, calls <code> lock()</code></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>lk.try_lock()</code></td>
|
||||
<td>If locked(), throws <code>lock_error</code>. Makes a non-blocking attempt
|
||||
to lock the associated mutex object, returning <code>true</code> if the
|
||||
lock attempt is successful, otherwise <code>false</code>. If the associated
|
||||
mutex object is already locked by the same thread the behavior is dependent
|
||||
on the <a href="mutex_concept.html#locking-strategies">locking strategy</a>
|
||||
of the associated mutex object.</td>
|
||||
</tr>
|
||||
</table>
|
||||
<h3><a name="ScopedTimedLock-concept"></a>ScopedTimedLock Concept</h3>
|
||||
<p>A ScopedTimedLock is a refinement of <a href="#Lock">Lock</a>. For a ScopedTimedLock
|
||||
type <code>L</code> and an object <code>lk</code> of that type, and an object
|
||||
<code>m</code> of a type meeting the <a href="mutex_concept.html#TimedMutex">TimedMutex</a>
|
||||
requirements, and an object <code>b</code> of type <code>bool</code>, and an
|
||||
object <code>t</code> of type <code><a href="xtime.html"> xtime</a></code>,
|
||||
the following expressions must be well-formed and have the indicated effects.</p>
|
||||
<table summary="ScopedTimedLock expressions" border="1" cellpadding=
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
|
||||
<title>Boost.Threads, Lock Concept</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">Lock Concepts</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Requirements">Concept Requirements</a><br>
|
||||
<a href="#Lock">Lock Concept</a><br>
|
||||
<a href="#ScopedLock">ScopedLock Concept</a><br>
|
||||
<a href="#ScopedTryLock">ScopedTryLock Concept</a><br>
|
||||
<a href="#ScopedTimedLock">ScopedTimedLock Concept</a><br>
|
||||
<a href="#Models">Models</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>The lock concepts provide exception safe means for locking and
|
||||
unlocking a <a href="mutex_concept.html">mutex model</a>. In other
|
||||
words they are an implementation of the <i>Scoped Locking</i> <a href=
|
||||
"bibliography.html#Schmidt 00">[Schmidt 00]</a> pattern. The <a href=
|
||||
"#ScopedLock">ScopedLock</a> concept, with <a href="#ScopedTryLock">
|
||||
ScopedTryLock</a> and <a href="#ScopedTimedLock">ScopedTimedLock</a>
|
||||
refinements, formalize the requirements.</p>
|
||||
|
||||
<p>Lock models are constructed with a reference to a <a href=
|
||||
"mutex_concept.html">mutex model</a> and typically acquire ownership of
|
||||
the <a href="mutex_concept.html">mutex model</a> by setting its state
|
||||
to locked. They also ensure ownership is relinquished in the
|
||||
destructor. Lock models also expose functions to query the lock status
|
||||
and to manually lock and unlock the <a href="mutex_concept.html">mutex
|
||||
model</a>.</p>
|
||||
|
||||
<p>Instances of lock models are meant to be short lived, expected to be
|
||||
used at block scope only. The lock models are not <a href=
|
||||
"definitions.html#Thread-safe">thread-safe</a>. Lock models must
|
||||
maintain state to indicate whether or not they've been locked and
|
||||
this state is not protected by any synchronization concepts. For this
|
||||
reason an instance of a lock model should never be shared between
|
||||
multiple threads.</p>
|
||||
|
||||
<h2>Concept <a name="Requirements">Requirements</a></h2>
|
||||
|
||||
<p>[For documentation purposes, portions of the concept requirements
|
||||
are repeated in the documentation for specific lock classes. Those
|
||||
copies need to be kept in sync with the requirements here.]</p>
|
||||
|
||||
<h3><a name="Lock">Lock</a> Concept</h3>
|
||||
|
||||
<p>For a <a href="#ScopedLock">ScopedLock</a>, <a href=
|
||||
"#ScopedTryLock">ScopedTryLock</a>, or <a href="#ScopedTimedLock">
|
||||
ScopedTimedLock</a> type <code>L</code> and an object <code>lk</code>
|
||||
and const object <code>clk</code> of that type, the following
|
||||
expressions must be well-formed and have the indicated effects.</p>
|
||||
|
||||
<p>The Lock concept is used as a base for the <a href="#ScopedLock">
|
||||
ScopedLock</a>, <a href="#ScopedTryLock">ScopedTryLock</a>, and <a
|
||||
href="#ScopedTimedLock">ScopedTimedLock</a> refinements. The associated
|
||||
mutex type is as specified for each of those refinements
|
||||
respectively.</p>
|
||||
|
||||
<table summary="Lock expressions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>(&lk)->~L();</code></td>
|
||||
|
||||
<td><code>if (locked()) unlock();</code></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>(&clk)->operator const
|
||||
void*()</code></td>
|
||||
|
||||
<td>Returns type void*, non-zero if if the associated mutex has
|
||||
been locked by <code>clk</code>, otherwise 0.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>clk.locked()</code></td>
|
||||
|
||||
<td>Returns a <code>bool</code>, <code>(&clk)->operator
|
||||
const void*() != 0</code></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>lk.lock()</code></td>
|
||||
|
||||
<td>Throws lock_error if locked(). If the associated mutex is
|
||||
already locked by some other thread, places the current thread
|
||||
in the <a href="definitions.html#State">Blocked</a> state until
|
||||
the associated mutex is unlocked, after which the current
|
||||
thread is placed in the <a href="definitions.html#State">
|
||||
Ready</a> state, eventually to be returned to the <a href=
|
||||
"definitions.html#State">Running</a> state.<br>
|
||||
Postcondition: locked()</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>lk.unlock()</code></td>
|
||||
|
||||
<td>If !locked(), throws lock_error, otherwise unlocks the
|
||||
associated mutex.<br>
|
||||
Postcondition: !locked()</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<h3><a name="ScopedLock">ScopedLock</a> Concept</h3>
|
||||
|
||||
<p>A ScopedLock must meet the <a href="#Lock">Lock</a> requirements.
|
||||
For a ScopedLock type <code>L</code> and an object <code>lk</code> of
|
||||
that type, and an object <code>m</code> of a type meeting the <a href=
|
||||
"mutex_concept.html#Mutex">Mutex</a> requirements, and an object <code>
|
||||
b</code> of type <code>bool</code>, the following expressions must be
|
||||
well-formed and have the indicated effects.</p>
|
||||
|
||||
<table summary="ScopedLock expressions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>L lk(m);</code></td>
|
||||
|
||||
<td>Constructs an object <code>lk</code>, and associates mutex
|
||||
<code>m</code> with it, then calls <code>lock()</code></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>L lk(m,b);</code></td>
|
||||
|
||||
<td>Constructs an object <code>lk</code>, and associates mutex
|
||||
<code>m</code> with it, then if <code>b</code>, calls <code>
|
||||
lock()</code></td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<h3><a name="ScopedTryLock">ScopedTryLock</a> Concept</h3>
|
||||
|
||||
<p>A ScopedTryLock must meet the <a href="#Lock">Lock</a> requirements.
|
||||
For a ScopedTryLock type <code>L</code> and an object <code>lk</code>
|
||||
of that type, and an object <code>m</code> of a type meeting the <a
|
||||
href="mutex_concept.html#TryMutex">TryMutex</a> requirements, and an
|
||||
object <code>b</code> of type <code>bool</code>, the following
|
||||
expressions must be well-formed and have the indicated effects.</p>
|
||||
|
||||
<table summary="ScopedTryLock expressions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>L lk(m);</code></td>
|
||||
|
||||
<td>Constructs an object <code>lk</code>, and associates mutex
|
||||
<code>m</code> with it, then calls <code>try_lock()</code></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>L lk(m,b);</code></td>
|
||||
|
||||
<td>Constructs an object <code>lk</code>, and associates mutex
|
||||
<code>m</code> with it, then if <code>b</code>, calls <code>
|
||||
lock()</code></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>lk.try_lock()</code></td>
|
||||
|
||||
<td>If locked(), throws <code>lock_error</code>. Makes a
|
||||
non-blocking attempt to lock the associated mutex, returning
|
||||
<code>true</code> if the lock attempt is successful, otherwise
|
||||
<code>false</code>.</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<h3><a name="ScopedTimedLock">ScopedTimedLock</a> Concept</h3>
|
||||
|
||||
<p>A ScopedTimedLock must meet the <a href="#Lock">Lock</a>
|
||||
requirements. For a ScopedTimedLock type <code>L</code> and an object
|
||||
<code>lk</code> of that type, and an object <code>m</code> of a type
|
||||
meeting the <a href="mutex_concept.html#TimedMutex">TimedMutex</a>
|
||||
requirements, and an object <code>b</code> of type <code>bool</code>,
|
||||
and an object <code>t</code> of type <code><a href="xtime.html">
|
||||
xtime</a></code>, the following expressions must be well-formed and
|
||||
have the indicated effects.</p>
|
||||
|
||||
<table summary="ScopedTimedLock expressions" border="1" cellpadding=
|
||||
"5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>L lk(m,t);</code></td>
|
||||
<td>Constructs an object <code>lk</code>, and associates mutex object <code>m</code>
|
||||
with it, then calls <code> timed_lock(t)</code></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>L lk(m,b);</code></td>
|
||||
<td>Constructs an object <code>lk</code>, and associates mutex object <code>m</code>
|
||||
with it, then if <code>b</code>, calls <code> lock()</code></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code>lk.timed_lock(t)</code></td>
|
||||
<td>If locked(), throws lock_error. Makes a blocking attempt to lock the associated
|
||||
mutex object, and returns <code>true</code> if successful within the specified
|
||||
time <code>t</code>, otherwise <code>false</code>. If the associated mutex
|
||||
object is already locked by the same thread the behavior is dependent on
|
||||
the <a href="mutex_concept.html#locking-strategies">locking strategy</a>
|
||||
of the associated mutex object.</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>L lk(m,t);</code></td>
|
||||
|
||||
<td>Constructs an object <code>lk</code>, and associates mutex
|
||||
<code>m</code> with it, then calls <code>
|
||||
timed_lock(t)</code></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>L lk(m,b);</code></td>
|
||||
|
||||
<td>Constructs an object <code>lk</code>, and associates mutex
|
||||
<code>m</code> with it, then if <code>b</code>, calls <code>
|
||||
lock()</code></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code>lk.timed_lock(t)</code></td>
|
||||
|
||||
<td>If locked(), throws lock_error. Makes a blocking attempt to
|
||||
lock the associated mutex, and returns <code>true</code> if
|
||||
successful within the specified time <code>t</code>, otherwise
|
||||
<code>false</code>.</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<h2><a name="Models">Models</a></h2>
|
||||
|
||||
<p><b>Boost.Threads</b> currently supplies three classes which model
|
||||
lock concepts.</p>
|
||||
|
||||
<p>These classes are normally accessed via typedefs of the same name
|
||||
supplied by a <a href="mutex_concept.html">mutex model</a>.</p>
|
||||
|
||||
<table summary="Lock concept classes" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Concept</b></td>
|
||||
|
||||
<td><b>Refines</b></td>
|
||||
|
||||
<td><b>Classes Modeling the Concept</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><a href="#ScopedLock">ScopedLock</a></td>
|
||||
|
||||
<td> </td>
|
||||
|
||||
<td><a href="scoped_lock.html">scoped_lock</a></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><a href="#ScopedTryLock">ScopedTryLock</a></td>
|
||||
|
||||
<td><a href="#ScopedLock">ScopedLock</a></td>
|
||||
|
||||
<td><a href="scoped_try_lock.html">scoped_try_lock</a> </td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><a href="#ScopedTimedLock">ScopedTimedLock</a></td>
|
||||
|
||||
<td><a href="#ScopedLock">ScopedLock</a></td>
|
||||
|
||||
<td><a href="scoped_timed_lock.html">scoped_timed_lock</a></td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
110
doc/lock_error.html
Normal file
110
doc/lock_error.html
Normal file
@@ -0,0 +1,110 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, lock_error</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">lock_error</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#Synopsis">Synopsis</a><br>
|
||||
<a href="#Members">Members</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>The <tt>lock_error</tt> class defines an exception type thrown to
|
||||
indicate a locking related error has been detected. Examples of such
|
||||
errors include a lock operation which can be determined to result in a
|
||||
deadlock, or unlock operations attempted by a thread that does not own
|
||||
the lock.</p>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/thread.hpp"><boost/thread/thread.hpp></a>
|
||||
</pre>
|
||||
|
||||
<h2><a name="Synopsis">Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost
|
||||
|
||||
class lock_error : public std::runtime_error
|
||||
{
|
||||
public:
|
||||
lock_error();
|
||||
};
|
||||
}
|
||||
</pre>
|
||||
|
||||
<h2><a name="Members">Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
lock_error();
|
||||
</pre>
|
||||
|
||||
<p>Constructs a <tt>lock_error</tt> object.</p>
|
||||
<hr>
|
||||
|
||||
<h2><a name="Example">Example</a> Usage</h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/mutex.hpp"><boost/thread/mutex.hpp></a>
|
||||
#include <a href=
|
||||
"../../../boost/thread/thread.hpp"><boost/thread/thread.hpp></a>
|
||||
#include <iostream>
|
||||
|
||||
int main(int, char*[])
|
||||
{
|
||||
boost::mutex mutex;
|
||||
boost::mutex::scoped_lock scoped_lock(mutex);
|
||||
try
|
||||
{
|
||||
boost::mutex::scoped_lock deadlock(mutex);
|
||||
std::cout << "lock succeeded" << std::endl;
|
||||
}
|
||||
catch (boost::lock_error& err)
|
||||
{
|
||||
std::cout << err.what() << " - deadlock occurred." << std::endl;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
</pre>
|
||||
|
||||
<p>The output is:</p>
|
||||
<pre>
|
||||
thread lock error - deadlock occurred.
|
||||
</pre>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
518
doc/mutex.html
518
doc/mutex.html
@@ -1,243 +1,359 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Header <boost/thread/mutex.hpp></title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Header <<a href="../../../boost/thread/mutex.hpp">boost/thread/mutex.hpp</a>></h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<h2>Contents</h2>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#classes">Classes</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-mutex">Class <code>mutex</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-mutex-synopsis">Class <code>mutex</code> synopsis</a></dt>
|
||||
<dt><a href="#class-mutex-ctors">Class <code>mutex</code> constructors and
|
||||
destructor</a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-try_mutex">Class <code>try_mutex</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-try_mutex-synopsis">Class <code>try_mutex</code> synopsis</a></dt>
|
||||
<dt><a href="#class-try_mutex-ctors">Class <code>try_mutex</code> constructors
|
||||
and destructor</a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-timed_mutex">Class <code>timed_mutex</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-timed_mutex-synopsis">Class <code>timed_mutex</code>
|
||||
synopsis</a></dt>
|
||||
<dt><a href="#class-timed_mutex-ctors">Class <code>timed_mutex</code> constructors
|
||||
and destructor</a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
<dt><a href="#examples">Example(s)</a></dt>
|
||||
</dl>
|
||||
<hr>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>Include the header <<a href="../../../boost/thread/mutex.hpp">boost/thread/mutex.hpp</a>>
|
||||
to define the <code><a href="#mutex Synopsis">mutex</a></code>, <code><a href=
|
||||
"#try_mutex Synopsis">try_mutex</a></code> and <code><a href=
|
||||
"#timed_mutex Synopsis">timed_mutex</a></code> classes.</p>
|
||||
<p>The <code><a href="#mutex Synopsis">mutex</a></code>, <code><a href=
|
||||
"#try_mutex Synopsis">try_mutex</a></code> and <code><a href=
|
||||
"#timed_mutex Synopsis">timed_mutex</a></code> classes are models of <a href="mutex_concept.html#Mutex-concept">Mutex</a>,
|
||||
<a href="mutex_concept.html#TryMutex-concept">TryMutex</a>, and <a href="mutex_concept.html#TimedMutex-concept">TimedMutex</a>
|
||||
respectively. These types should be used to non-recursively synchronize access
|
||||
to shared resources. For recursive locking mechanics, see the <a href="recursive_mutex.html">recursive
|
||||
mutexes</a> supplied by <b>Boost.Threads</b>.</p>
|
||||
<p>Each class supplies one or more typedefs for lock types which model matching
|
||||
lock concepts. For the best possible performance you should use the mutex class
|
||||
that supports the minimum set of lock types that you need.</p>
|
||||
<table summary="lock types" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Mutex Class</b></td>
|
||||
<td><b>Lock name</b></td>
|
||||
<td><b>Lock Concept</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><a href="#mutex Synopsis"><code> mutex</code></a></td>
|
||||
<td valign="middle"><code>scoped_lock</code></td>
|
||||
<td valign="middle"><a href="lock_concept.html#ScopedLock"> ScopedLock</a></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code><a href="#try_mutex Synopsis"> try_mutex</a></code>
|
||||
</td>
|
||||
<td valign="middle"><code>scoped_lock<br>
|
||||
scoped_try_lock</code></td>
|
||||
<td valign="middle"><a href="lock_concept.html#ScopedLock"> ScopedLock</a><br>
|
||||
<a href="lock_concept.html#ScopedTryLock"> ScopedTryLock</a></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code><a href="#timed_mutex Synopsis"> timed_mutex</a></code>
|
||||
</td>
|
||||
<td valign="middle"><code>scoped_lock<br>
|
||||
scoped_try_lock<br>
|
||||
scoped_timed_lock</code></td>
|
||||
<td valign="middle"><a href="lock_concept.html#ScopedLock"> ScopedLock</a><br>
|
||||
<a href="lock_concept.html#ScopedTryLock"> ScopedTryLock</a><br>
|
||||
<a href="lock_concept.html#ScopedTimedLock"> ScopedTimedLock</a></td>
|
||||
</tr>
|
||||
</table>
|
||||
<p>The <code>mutex</code>, <code>try_mutex</code> and <code>timed_mutex</code>
|
||||
classes use an <code>Unspecified</code> <a href="mutex_concept.html#LockingStrategies">locking
|
||||
strategy</a>, so attempts to recursively lock them or attempts to unlock them
|
||||
by threads that don't own a lock on them result in <b>undefined behavior</b>.
|
||||
This strategy allows implementations to be as efficient as possible on any given
|
||||
platform. It is, however, recommended that implementations include debugging
|
||||
support to detect misuse when <code>NDEBUG</code> is not defined.</p>
|
||||
<p>Like all the <b>Boost.Threads</b> <a href="mutex_concept.html">mutex models</a>,
|
||||
the <code>mutex</code>, <code>try_mutex</code> and <code> timed_mutex</code>
|
||||
leave the <a href="mutex_concept.html#SchedulingPolicies">scheduling policy</a>
|
||||
as <code> Unspecified</code>. Programmers should make no assumptions about the
|
||||
order in which waiting threads acquire a lock.</p>
|
||||
<h2><a name="classes"></a>Classes</h2>
|
||||
<h3><a name="class-mutex"></a>Class <code>mutex</code></h3>
|
||||
<p>The <code>mutex</code> class is a model of <a href="mutex_concept.html#Mutex-concept">Mutex</a>
|
||||
and <a href="overview.html#non-copyable">NonCopyable</a>, and provides no additional
|
||||
facilities beyond the requirements of these concepts.</p>
|
||||
<h4><a name="class-mutex-synopsis"></a>Class <code>mutex</code> synopsis</h4>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, mutex</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#ffffff" link="#0000ff" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img alt="C++ Boost" src="../../../c++boost.gif" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">mutex<br>
|
||||
try_mutex<br>
|
||||
timed_mutex</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#mutex Synopsis">Class mutex Synopsis</a><br>
|
||||
<a href="#mutex Members">Class mutex Members</a><br>
|
||||
<a href="#try_mutex Synopsis">Class try_mutex Synopsis</a><br>
|
||||
<a href="#try_mutex Members">Class try_mutex Members</a><br>
|
||||
<a href="#timed_mutex Synopsis">Class timed_mutex Synopsis</a><br>
|
||||
<a href="#timed_mutex Members">Class timed_mutex Members</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>The <tt><a href="#mutex Synopsis">mutex</a></tt>, <tt><a href=
|
||||
"#try_mutex Synopsis">try_mutex</a></tt> and <tt><a href=
|
||||
"#timed_mutex Synopsis">timed_mutex</a></tt> classes define full
|
||||
featured models of the <a href="mutex_concept.html#Mutex">Mutex</a>, <a
|
||||
href="mutex_concept.html#TryMutex">TryMutex</a>, and <a href=
|
||||
"mutex_concept.html#TimedMutex">TimedMutex</a> concepts. These types
|
||||
should be used to non-recursively synchronize access to shared
|
||||
resources. For recursive locking mechanics, see <a href=
|
||||
"recursive_mutex.html">recursive mutexes</a>.</p>
|
||||
|
||||
<p>Each class supplies one or more typedefs for lock types which model
|
||||
matching lock concepts. For the best possible performance you should
|
||||
use the mutex class that supports the minimum set of lock types that
|
||||
you need.</p>
|
||||
|
||||
<table summary="lock types" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Mutex Class</b></td>
|
||||
|
||||
<td><b>Lock name</b></td>
|
||||
|
||||
<td><b>Implementation defined Lock Type</b></td>
|
||||
|
||||
<td><b>Lock Concept</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><a href="#mutex Synopsis"><code>
|
||||
mutex</code></a></td>
|
||||
|
||||
<td valign="middle"><code>scoped_lock</code></td>
|
||||
|
||||
<td valign="middle"><code><a href="scoped_lock.html">
|
||||
boost::</a></code><a href=
|
||||
"scoped_lock.html"><code>detail::thread::scoped_lock<mutex></code></a></td>
|
||||
|
||||
<td valign="middle"><a href="lock_concept.html#ScopedLock">
|
||||
ScopedLock</a></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><tt><a href="#try_mutex Synopsis">
|
||||
try_mutex</a></tt> </td>
|
||||
|
||||
<td valign="middle"><code>scoped_lock<br>
|
||||
scoped_try_lock</code></td>
|
||||
|
||||
<td valign="middle"><code><a href="scoped_lock.html">
|
||||
boost::</a></code><a href=
|
||||
"scoped_lock.html"><code>detail::thread::scoped_lock<try_mutex><br>
|
||||
|
||||
</code></a> <code><a href="scoped_try_lock.html">
|
||||
boost::detail::thread::scoped_try_lock<try_mutex></a></code></td>
|
||||
|
||||
<td valign="middle"><a href="lock_concept.html#ScopedLock">
|
||||
ScopedLock</a><br>
|
||||
<a href="lock_concept.html#ScopedTryLock">
|
||||
ScopedTryLock</a></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code><a href="#timed_mutex Synopsis">
|
||||
timed_mutex</a></code> </td>
|
||||
|
||||
<td valign="middle"><code>scoped_lock<br>
|
||||
scoped_try_lock<br>
|
||||
scoped_timed_lock</code></td>
|
||||
|
||||
<td valign="middle"><code><a href="scoped_lock.html">
|
||||
boost::</a></code><a href=
|
||||
"scoped_lock.html"><code>detail::thread::scoped_lock<timed_mutex></code></a><br>
|
||||
|
||||
<code><a href="scoped_try_lock.html">boost::</a></code><a
|
||||
href=
|
||||
"scoped_try_lock.html"><code>detail::thread::scoped_try_lock<timed_mutex></code></a><br>
|
||||
|
||||
<code><a href="scoped_timed_lock.html">boost::</a></code><a
|
||||
href=
|
||||
"scoped_timed_lock.html"><code>detail::thread::scoped_timed_lock<timed_mutex></code></a></td>
|
||||
|
||||
<td valign="middle"><a href="lock_concept.html#ScopedLock">
|
||||
ScopedLock</a><br>
|
||||
<a href="lock_concept.html#ScopedTryLock">
|
||||
ScopedTryLock</a><br>
|
||||
<a href="lock_concept.html#ScopedTimedLock">
|
||||
ScopedTimedLock</a></td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<p>The <tt>mutex</tt>, <tt>try_mutex</tt> and <tt>timed_mutex</tt>
|
||||
classes use an <tt>Unspecified</tt> <a href=
|
||||
"mutex_concept.html#LockingStrategies">locking strategy</a>, so
|
||||
attempts to recursively lock them or attempts to unlock them by threads
|
||||
that don't own a lock on them result in <b>undefined behavior</b>.
|
||||
This strategy allows implementations to be as efficient as possible on
|
||||
any given platform. It is, however, recommended that implementations
|
||||
include debugging support to detect misuse when <tt>NDEBUG</tt> is not
|
||||
defined.</p>
|
||||
|
||||
<p>Like all the <b>Boost.Threads</b> <a href="mutex_concept.html">mutex
|
||||
models</a>, the <tt>mutex</tt>, <tt>try_mutex</tt> and <tt>
|
||||
timed_mutex</tt> leave the <a href=
|
||||
"mutex_concept.html#SchedulingPolicies">scheduling policy</a> as <tt>
|
||||
Unspecified</tt>. Programmers should assume that threads waiting for a
|
||||
lock on objects of these types acquire the lock in a random order, even
|
||||
though the specific behavior for a given platform may be different.</p>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/mutex.hpp"><boost/thread/mutex.hpp></a>
|
||||
</pre>
|
||||
|
||||
<h2>Class <a name="mutex Synopsis">mutex Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
class mutex : private <a href="../../utility/utility.htm">boost::noncopyable</a> // Exposition only.
|
||||
// Class mutex meets the <a href="overview.html#non-copyable">NonCopyable</a> requirement.
|
||||
class mutex : private <a href=
|
||||
"../../utility/utility.htm">boost::noncopyable</a> // Exposition only.
|
||||
// Class mutex meets the <a href=
|
||||
"overview.html#NonCopyable">NonCopyable</a> requirement.
|
||||
{
|
||||
public:
|
||||
typedef <i>[implementation defined; see <a href="#Introduction">Introduction</a>]</i> scoped_lock;
|
||||
|
||||
typedef <i>[implementation defined; see <a href=
|
||||
"#Introduction">Introduction</a>]</i> scoped_lock;
|
||||
|
||||
mutex();
|
||||
~mutex();
|
||||
};
|
||||
};
|
||||
}
|
||||
</pre>
|
||||
<h4><a name="class-mutex-ctors"></a>Class <code>mutex</code> constructors and
|
||||
destructor</h4>
|
||||
|
||||
<h2>Class <a name="mutex Members">mutex Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
mutex();
|
||||
mutex();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Postconditions:</b> <code>*this</code> is in an unlocked state.</dt>
|
||||
</dl>
|
||||
|
||||
<p><b>Postconditions:</b> <code>*this</code> is in the unlocked
|
||||
state.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~mutex();
|
||||
~mutex();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> <code>*this</code> is in an unlocked sate.</dt>
|
||||
<dt><b>Danger:</b> Destruction of a locked mutex is a serious programming error
|
||||
resulting in undefined behavior such as a program crash.</dt>
|
||||
</dl>
|
||||
<h3><a name="class-try_mutex"></a>Class <code>try_mutex</code></h3>
|
||||
<p>The <code>try_mutex</code> class is a model of <a href="mutex_concept.html#TryMutex-concept">TryMutex</a>
|
||||
and <a href="overview.html#non-copyable">NonCopyable</a>, and provides no additional
|
||||
facilities beyond the requirements of these concepts.</p>
|
||||
<h4><a name="class-try_mutex-synopsis"></a>Class <code>try_mutex</code> synopsis</h4>
|
||||
|
||||
<p><b>Requires:</b> <code>*this</code> is in the unlocked state.</p>
|
||||
|
||||
<p><b>Effects:</b> Destroys <code>*this</code>.</p>
|
||||
|
||||
<p><b>Dangers:</b> Destruction of a locked mutex is a serious
|
||||
programming error resulting in undefined behavior such as a program
|
||||
crash.</p>
|
||||
<hr>
|
||||
|
||||
<h2>Class <a name="try_mutex Synopsis">try_mutex Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
class try_mutex : private <a href="../../utility/utility.htm">boost::noncopyable</a> // Exposition only.
|
||||
// Class try_mutex meets the <a href="overview.html#non-copyable">NonCopyable</a> requirement.
|
||||
class try_mutex : private boost::noncopyable // Exposition only.
|
||||
// Class try_mutex meets the <a href=
|
||||
"overview.html#NonCopyable">NonCopyable</a> requirement.
|
||||
{
|
||||
Public:
|
||||
typedef <i>[implementation defined; see <a href="#Introduction">Introduction</a>]</i> scoped_lock;
|
||||
typedef <i>[implementation defined; see <a href="#Introduction">Introduction</a>]</i> scoped_try_lock;
|
||||
|
||||
public:
|
||||
typedef <i>[implementation defined; see <a href=
|
||||
"#Introduction">Introduction</a>]</i> scoped_lock;
|
||||
typedef <i>[implementation defined; see <a href=
|
||||
"#Introduction">Introduction</a>]</i> scoped_try_lock;
|
||||
|
||||
try_mutex();
|
||||
~try_mutex();
|
||||
};
|
||||
};
|
||||
}
|
||||
</pre>
|
||||
<h4><a name="class-try_mutex-ctors"></a>Class <code>try_mutex</code> constructors
|
||||
and destructor</h4>
|
||||
|
||||
<h2>Class <a name="try_mutex Members">try_mutex Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
try_mutex();
|
||||
try_mutex();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Postconditions:</b> <code>*this</code> is in an unlocked state.</dt>
|
||||
</dl>
|
||||
|
||||
<p><b>Postconditions:</b> <code>*this</code> is in the unlocked
|
||||
state.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~try_mutex();
|
||||
~try_mutex();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> <code>*this</code> is in an unlocked sate.</dt>
|
||||
<dt><b>Danger:</b> Destruction of a locked mutex is a serious programming error
|
||||
resulting in undefined behavior such as a program crash.</dt>
|
||||
</dl>
|
||||
<h3><a name="class-timed_mutex"></a>Class <code>timed_mutex</code></h3>
|
||||
<p>The <code>timed_mutex</code> class is a model of <a href="mutex_concept.html#TimedMutex-concept">TimedMutex</a>
|
||||
and <a href="overview.html#non-copyable">NonCopyable</a>, and provides no additional
|
||||
facilities beyond the requirements of these concepts.</p>
|
||||
<h4><a name="class-timed_mutex-synopsis"></a>Class <code>timed_mutex</code> synopsis</h4>
|
||||
|
||||
<p><b>Requires:</b> <code>*this</code> is in the unlocked state.</p>
|
||||
|
||||
<p><b>Effects:</b> Destroys <code>*this</code>.</p>
|
||||
|
||||
<p><b>Dangers:</b> Destruction of a locked mutex is a serious
|
||||
programming error resulting in undefined behavior such as a program
|
||||
crash.</p>
|
||||
<hr>
|
||||
|
||||
<h2>Class <a name="timed_mutex Synopsis">timed_mutex Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
class timed_mutex : private <a href="../../utility/utility.htm">boost::noncopyable</a> // Exposition only.
|
||||
// Class timed_mutex meets the <a href="overview.html#non-copyable">NonCopyable</a> requirement.
|
||||
class timed_mutex : private boost::noncopyable // Exposition only.
|
||||
// Class timed_mutex meets the <a href=
|
||||
"overview.html#NonCopyable">NonCopyable</a> requirement.
|
||||
{
|
||||
Public:
|
||||
typedef <i>[implementation defined; see <a href="#Introduction">Introduction</a>]</i> scoped_lock;
|
||||
typedef <i>[implementation defined; see <a href="#Introduction">Introduction</a>]</i> scoped_try_lock;
|
||||
typedef <i>[implementation defined; see <a href="#Introduction">Introduction</a>]</i> scoped_timed_lock;
|
||||
|
||||
public:
|
||||
typedef <i>[implementation defined; see <a href=
|
||||
"#Introduction">Introduction</a>]</i> scoped_lock;
|
||||
typedef <i>[implementation defined; see <a href=
|
||||
"#Introduction">Introduction</a>]</i> scoped_try_lock;
|
||||
typedef <i>[implementation defined; see <a href=
|
||||
"#Introduction">Introduction</a>]</i> scoped_timed_lock;
|
||||
|
||||
timed_mutex();
|
||||
~timed_mutex();
|
||||
};
|
||||
}
|
||||
</pre>
|
||||
|
||||
<h2>Class <a name="timed_mutex Members">timed_mutex Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
timed_mutex();
|
||||
</pre>
|
||||
|
||||
<p><b>Postconditions:</b> <code>*this</code> is in the unlocked
|
||||
state.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~timed_mutex();
|
||||
</pre>
|
||||
|
||||
<p><b>Requires:</b> <code>*this</code> is in the unlocked state.</p>
|
||||
|
||||
<p><b>Effects:</b> Destroys <code>*this</code>.</p>
|
||||
|
||||
<p><b>Dangers:</b> Destruction of a locked mutex is a serious
|
||||
programming error resulting in undefined behavior such as a program
|
||||
crash.</p>
|
||||
<hr>
|
||||
|
||||
<h2><a name="Example">Example</a> Usage</h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/mutex.hpp"><boost/thread/mutex.hpp></a>
|
||||
#include <a href=
|
||||
"../../../boost/thread/thread.hpp"><boost/thread/thread.hpp></a>
|
||||
#include <iostream>
|
||||
|
||||
boost::mutex io_mutex; // The iostreams are not guaranteed to be <a href=
|
||||
"definitions.html#Thread-safe">thread-safe</a>!
|
||||
|
||||
class counter
|
||||
{
|
||||
public:
|
||||
counter() : count(0) { }
|
||||
|
||||
int increment() {
|
||||
boost::mutex::scoped_lock scoped_lock(mutex);
|
||||
return ++count;
|
||||
}
|
||||
|
||||
private:
|
||||
boost::mutex mutex;
|
||||
int count;
|
||||
};
|
||||
|
||||
counter c;
|
||||
|
||||
void change_count(void*)
|
||||
{
|
||||
int i = c.increment();
|
||||
boost::mutex::scoped_lock scoped_lock(io_mutex);
|
||||
std::cout << "count == " << i << std::endl;
|
||||
}
|
||||
|
||||
int main(int, char*[])
|
||||
{
|
||||
const int num_threads = 4;
|
||||
boost::thread_group thrds;
|
||||
for (int i=0; i < num_threads; ++i)
|
||||
thrds.create_thread(&change_count, 0);
|
||||
|
||||
thrds.join_all();
|
||||
|
||||
return 0;
|
||||
}
|
||||
</pre>
|
||||
<h4><a name="class-timed_mutex-ctors"></a>Class <code>timed_mutex</code> constructors
|
||||
and destructor</h4>
|
||||
<pre>
|
||||
timed_mutex();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Postconditions:</b> <code>*this</code> is in an unlocked state.</dt>
|
||||
</dl>
|
||||
<pre>
|
||||
~timed_mutex();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> <code>*this</code> is in an unlocked sate.</dt>
|
||||
<dt><b>Danger:</b> Destruction of a locked mutex is a serious programming error
|
||||
resulting in undefined behavior such as a program crash.</dt>
|
||||
</dl>
|
||||
<h2><a name="examples"></a>Example(s)</h2>
|
||||
<p><a href="../example/mutex.cpp">libs/thread/example/mutex.cpp</a></p>
|
||||
<p>The output is:</p>
|
||||
|
||||
<p>The output is:</p>
|
||||
<pre>
|
||||
count == 1
|
||||
count == 2
|
||||
count == 3
|
||||
count == 4
|
||||
</pre>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
@@ -1,237 +1,337 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Mutex Concept</title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300"> <a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Mutex Concept</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#locking-strategies">Locking Strategies</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#locking-strategy-recursive">Recursive</a></dt>
|
||||
<dt><a href="#locking-strategy-checked">Checked</a></dt>
|
||||
<dt><a href="#locking-strategy-unchecked">Unchecked</a></dt>
|
||||
<dt><a href="#locking-strategy-unspecified">Unspecified</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#scheduling-policies">Scheduling Policies</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#scheduling-policy-FIFO">FIFO</a></dt>
|
||||
<dt><a href="#scheduling-policy-priority-driven">Priority Driven</a></dt>
|
||||
<dt><a href="#scheduling-policy-unspecified">Unspecified</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#concept-requirements">Concept Requirements</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#Mutex-concept">Mutex Concept</a></dt>
|
||||
<dt><a href="#TryMutex-concept">TryMutex Concept</a></dt>
|
||||
<dt><a href="#TimedMutex-concept">TimedMutex Concept</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#models">Models</a></dt>
|
||||
</dl>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>A mutex (short for mutual-exclusion) object is used to serializes access to
|
||||
a resource shared between multiple threads. The <a href="#Mutex">Mutex</a> concept,
|
||||
with <a href="#TryMutex">TryMutex</a> and <a href="#TimedMutex">TimedMutex</a>
|
||||
refinements, formalize the requirements. A model that implements Mutex and its
|
||||
refinements has two states: <b>locked</b> and <b>unlocked</b>. Before using
|
||||
a shared resource, a thread locks a <b>Boost.Threads</b> mutex object (an object
|
||||
whose type is a model of <a href="#Mutex-concept">Mutex</a> or one of it's
|
||||
refinements), insuring <a href="definitions.html#thread-safe">thread-safe</a>
|
||||
access to the shared resource. When use of the shared resource is complete,
|
||||
the thread unlocks the mutex object, allowing another thread to acquire the
|
||||
lock and use the shared resource.</p>
|
||||
<p>Traditional C thread APIs, like POSIX threads or the Windows thread APIs, expose
|
||||
functions to lock and unlock a mutex object. This is dangerous since it's
|
||||
easy to forget to unlock a locked mutex. When the flow of control is complex,
|
||||
with multiple return points, the likelihood of forgetting to unlock a mutex
|
||||
object would become even greater. When exceptions are thrown, it becomes nearly
|
||||
impossible to ensure that the mutex object is unlocked properly when using these
|
||||
traditional API's. The result is <a href="definitions.html#deadlock">deadlock</a>.</p>
|
||||
<p>Many C++ threading libraries use a pattern known as <i>Scoped Locking</i> <a href="bibliography.html#Schmidt-00">[Schmidt
|
||||
00]</a> to free the programmer from the need to explicitly lock and unlock mutex
|
||||
objects. With this pattern, a <a href="lock_concept.html">Lock</a> concept is
|
||||
employed where the lock object's constructor locks the associated mutex
|
||||
object and the destructor automatically does the unlocking. The <b>Boost.Threads</b>
|
||||
library takes this pattern to the extreme in that Lock concepts are the only
|
||||
way to lock and unlock a mutex object: lock and unlock functions are not exposed
|
||||
by any <b>Boost.Threads</b> mutex objects. This helps to ensure safe usage patterns,
|
||||
especially when code throws exceptions.</p>
|
||||
<h2><a name="locking-strategies"></a>Locking Strategies</h2>
|
||||
<p>Every mutex object follows one of several locking strategies. These strategies
|
||||
define the semantics for the locking operation when the calling thread already
|
||||
owns a lock on the mutex object.</p>
|
||||
<h3><a name="locking-strategy-recursive"></a>Recursive</h3>
|
||||
<p>With a recursive locking strategy when a thread attempts to acquire a lock
|
||||
on the mutex object for which it already owns a lock, the operation is successful.
|
||||
Note the distinction between a thread, which may have multiple locks outstanding
|
||||
on a recursive mutex object, and a lock object, which even for a recursive mutex
|
||||
object cannot have any of its lock functions called multiple times without first
|
||||
calling unlock.</p>
|
||||
<p>Internally a lock count is maintained and the owning thread must unlock the
|
||||
mutex model the same number of times that it's locked it before the mutex
|
||||
object's state returns to unlocked. Since mutex objects in <b>Boost.Threads</b>
|
||||
expose locking functionality only through lock concepts, a thread will always
|
||||
unlock a mutex object the same number of times that it locked it. This helps
|
||||
to eliminate a whole set of errors typically found in traditional C style thread
|
||||
APIs.</p>
|
||||
<p>Classes <a href="recursive_mutex.html#class-recursive_mutex">recursive_mutex</a>,
|
||||
<a href="recursive_mutex.html#class-recursive_try_mutex">recursive_try_mutex</a>
|
||||
and <a href="recursive_mutex.html#class-recursive_timed_mutex">recursive_timed_mutex</a>
|
||||
use this locking strategy.</p>
|
||||
<h3><a name="locking-strategy-checked"></a>Checked</h3>
|
||||
<p>With a checked locking strategy when a thread attempts to acquire a lock on
|
||||
the mutex object for which the thread already owns a lock, the operation will
|
||||
fail with some sort of error indication. Further, attempts by a thread to unlock
|
||||
a mutex object that was not locked by the thread will also return some sort
|
||||
of error indication. In <b>Boost.Threads</b>, an exception of type <a href="exceptions.html#class-lock_error">
|
||||
lock_error</a> would be thrown in these cases.</p>
|
||||
<p><b>Boost.Threads</b> does not currently provide any mutex objects that use
|
||||
this strategy.</p>
|
||||
<h3><a name="locking-strategy-unchecked"></a>Unchecked</h3>
|
||||
<p>With an unchecked locking strategy when a thread attempts to acquire a lock
|
||||
on a mutex object for which the thread already owns a lock the operation will
|
||||
<a href="definitions.html#definition-deadlock">deadlock</a>. In general this
|
||||
locking strategy is less safe than a checked or recursive strategy, but it's
|
||||
also a faster strategy and so is employed by many libraries.</p>
|
||||
<p><b>Boost.Threads</b> does not currently provide any mutex objects that use
|
||||
this strategy.</p>
|
||||
<h3><a name="locking-strategy-unspecified"></a>Unspecified</h3>
|
||||
<p>With an unspecified locking strategy, when a thread attempts to acquire a lock
|
||||
on a mutex object for which the thread already owns a lock the operation results
|
||||
in <b>undefined behavior</b>.</p>
|
||||
<p>In general a mutex object with an unspecified locking strategy is unsafe, and
|
||||
it requires programmer discipline to use the mutex object properly. However,
|
||||
this strategy allows an implementation to be as fast as possible with no restrictions
|
||||
on its implementation. This is especially true for portable implementations
|
||||
that wrap the native threading support of a platform. For this reason, the classes
|
||||
<a href="mutex.html#class-mutex">mutex</a>, <a href="mutex.html#class-try_mutex">try_mutex</a>
|
||||
and <a href="mutex.html#class-timed_mutex">timed_mutex</a> use this locking
|
||||
strategy despite the lack of safety.</p>
|
||||
<h2><a name="scheduling-policies"></a>Scheduling Policies</h2>
|
||||
<p>Every mutex object follows one of several scheduling policies. These policies
|
||||
define the semantics when the mutex object is unlocked and there is more than
|
||||
one thread waiting to acquire a lock. In other words, the policy defines which
|
||||
waiting thread shall acquire the lock.</p>
|
||||
<h3><a name="scheduling-policy-FIFO"></a>FIFO</h3>
|
||||
<p>With a FIFO scheduling policy, threads waiting for the lock will acquire it
|
||||
in a first come first serve order (or First In First Out). This can help prevent
|
||||
a high priority thread from starving lower priority threads that are also waiting
|
||||
on the mutex object's lock.</p>
|
||||
<h3><a name="scheduling-policy-priority-driven"></a>Priority Driven</h3>
|
||||
<p>With a Priority Driven scheduling policy, the thread with the highest priority
|
||||
acquires the lock. Note that this means that low-priority threads may never
|
||||
acquire the lock if the mutex object has high contention and there is always
|
||||
at least one high-priority thread waiting. This is known as thread starvation.
|
||||
When multiple threads of the same priority are waiting on the mutex object's
|
||||
lock one of the other scheduling priorities will determine which thread shall
|
||||
acquire the lock.</p>
|
||||
<h3><a name="scheduling-policy-unspecified"></a>Unspecified</h3>
|
||||
<p>The mutex object does not specify a scheduling policy. In order to ensure portability,
|
||||
all <b>Boost.Threads</b> mutex models use an unspecified scheduling policy.</p>
|
||||
<h2><a name="concept-requirements"></a>Concept Requirements</h2>
|
||||
<h3><a name="Mutex-concept"></a>Mutex Concept</h3>
|
||||
<p>A Mutex object has two states: locked and unlocked. Mutex object state can
|
||||
only be determined by an object meeting the <a href="lock_concept.html#ScopedLock">ScopedLock</a>
|
||||
requirements and constructed for the Mutex object.</p>
|
||||
<p>A Mutex is <a href="../../utility/utility.htm#Class_noncopyable">NonCopyable</a>.</p>
|
||||
<p>For a Mutex type M and an object m of that type, the following expressions
|
||||
must be well-formed and have the indicated effects.</p>
|
||||
<table summary="Mutex expressions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td><code>M m;</code></td>
|
||||
<td>Constructs a mutex object m. Post-condition: m is unlocked.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td><code>(&m)->~M();</code></td>
|
||||
<td>Precondition: m is unlocked. Destroys a mutex object m.</td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td><code>M::scoped_lock</code></td>
|
||||
<td>A model of <a href="lock_concept.html#ScopedLock">ScopedLock</a>.</td>
|
||||
</tr>
|
||||
</table>
|
||||
<h3><a name="TryMutex-concept"></a>TryMutex Concept</h3>
|
||||
<p>A TryMutex is a refinement of <a href="#Mutex-concept">Mutex</a>. For a TryMutex
|
||||
type M and an object m of that type, the following expressions must be well-formed
|
||||
and have the indicated effects.</p>
|
||||
<table summary="TryMutex expressions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td><code>M::scoped_try_lock</code></td>
|
||||
<td>A model of <a href="lock_concept.html#ScopedTryLock">ScopedTryLock</a>.</td>
|
||||
</tr>
|
||||
</table>
|
||||
<h3><a name="TimedMutex-concept"></a>TimedMutex Concept</h3>
|
||||
<p>A TimedMutex is a refinement of <a href="#TryMutex-concept">TryMutex</a>. For
|
||||
a TimedMutex type M and an object m of that type, the following expressions
|
||||
must be well-formed and have the indicated effects.</p>
|
||||
<table summary="TimedMutex expressions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td><code>M::scoped_timed_lock</code></td>
|
||||
<td>A model of <a href="lock_concept.html#ScopedTimedLock">ScopedTimedLock</a>.</td>
|
||||
</tr>
|
||||
</table>
|
||||
<h2><a name="models"></a>Models</h2>
|
||||
<p><b>Boost.Threads</b> currently supplies six models of Mutex.</p>
|
||||
<table summary="Mutex concept classes" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Concept</b></td>
|
||||
<td><b>Refines</b></td>
|
||||
<td><b>Models</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><a href="#Mutex-concept">Mutex</a></td>
|
||||
<td valign="top"> </td>
|
||||
<td><a href="mutex.html">mutex</a><br>
|
||||
<a href="recursive_mutex.html">recursive_mutex</a></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><a href="#TryMutex-concept">TryMutex</a></td>
|
||||
<td valign="top"><a href="#Mutex-concept">Mutex</a></td>
|
||||
<td><a href="mutex.html">try_mutex<br>
|
||||
</a> <a href="recursive_mutex.html">recursive_try_mutex</a> </td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><a href="#TimedMutex-concept">TimedMutex</a></td>
|
||||
<td valign="top"><a href="#TryMutex-concept">TryMutex</a></td>
|
||||
<td><a href="mutex.html">timed_mutex<br>
|
||||
</a> <a href="recursive_mutex.html"> recursive_timed_mutex</a></td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->09 January, 2003<!--webbot bot="Timestamp" endspan i-checksum="38582" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
|
||||
<title>Boost.Threads, Mutex Concept</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#ffffff" link="#0000ff" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img height="86" alt="C++ Boost" src=
|
||||
"../../../c++boost.gif" width="277"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">Mutex Concepts</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#LockingStrategies">Locking Strategies</a><br>
|
||||
<a href="#Recursive">Recursive</a><br>
|
||||
<a href="#CheckedStrategy">Checked</a><br>
|
||||
<a href="#UncheckedStrategy">Unchecked</a><br>
|
||||
<a href="#UnspecifiedStrategy">
|
||||
Unspecified</a><br>
|
||||
<a href="#SchedulingPolicies">Scheduling Policies</a><br>
|
||||
<a href="#FIFO">FIFO</a><br>
|
||||
<a href="#Priority Driven">Priority
|
||||
Driven</a><br>
|
||||
<a href="#UndefinedScheduling">
|
||||
Undefined</a><br>
|
||||
<a href="#UnspecifiedScheduling">
|
||||
Unspecified</a><br>
|
||||
<a href="#Requirements">Concept Requirements</a><br>
|
||||
<a href="#Mutex">Mutex Concept</a><br>
|
||||
<a href="#TryMutex">TryMutex Concept</a><br>
|
||||
<a href="#TimedMutex">TimedMutex
|
||||
Concept</a><br>
|
||||
<a href="#Models">Models</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>A mutex (short for mutual-exclusion) concept serializes access to a
|
||||
resource shared between multiple threads. The <a href="#Mutex">
|
||||
Mutex</a> concept, with <a href="#TryMutex">TryMutex</a> and <a href=
|
||||
"#TimedMutex">TimedMutex</a> refinements, formalize the requirements. A
|
||||
model that implements Mutex and its refinements has two states: <b>
|
||||
locked</b> and <b>unlocked</b>. Before using a shared resource, a
|
||||
thread locks a Boost.Threads mutex model object, insuring <a href=
|
||||
"definitions.html#Thread-safe">thread-safe</a> access to the shared
|
||||
resource. When use of the shared resource is complete, the thread
|
||||
unlocks the mutex model object, allowing another thread to acquire the
|
||||
lock and use the shared resource.</p>
|
||||
|
||||
<p>Traditional C thread APIs, like Pthreads or the Windows thread APIs,
|
||||
expose functions to lock and unlock a mutex model. This is dangerous
|
||||
since it's easy to forget to unlock a locked mutex. When the flow
|
||||
of control is complex, with multiple return points, the likelihood of
|
||||
forgetting to unlock a mutex model would become even greater. When
|
||||
exceptions are thrown, it becomes nearly impossible to ensure that the
|
||||
mutex is unlocked properly when using these traditional API's. The
|
||||
result is <a href="definitions.html#Deadlock">deadlock</a>.</p>
|
||||
|
||||
<p>Many C++ threading libraries use a pattern known as <i>Scoped
|
||||
Locking</i> <a href="bibliography.html#Schmidt 00">[Schmidt 00]</a> to
|
||||
free the programmer from the need to explicitly lock and unlock
|
||||
mutexes. With this pattern, a <a href="lock_concept.html">lock
|
||||
concept</a> is employed where the lock model's constructor locks
|
||||
the associated mutex model and the destructor automatically does the
|
||||
unlocking. The <b>Boost.Threads</b> library takes this pattern to the
|
||||
extreme in that lock concepts are the only way to lock and unlock a
|
||||
mutex model: lock and unlock functions are not exposed by any <b>
|
||||
Boost.Threads</b> mutex models. This helps to ensure safe usage
|
||||
patterns, especially when code throws exceptions.</p>
|
||||
|
||||
<h2><a name="LockingStrategies">Locking Strategies</a></h2>
|
||||
|
||||
<p>Every mutex model follows one of several locking strategies. These
|
||||
strategies define the semantics for the locking operation when the
|
||||
calling thread already owns a lock on the mutex model.</p>
|
||||
|
||||
<h3><a name="Recursive">Recursive</a></h3>
|
||||
|
||||
<p>With a recursive locking strategy when a thread attempts to acquire
|
||||
a lock on the mutex model for which it already owns a lock, the
|
||||
operation is successful. Note the distinction between a thread, which
|
||||
may have multiple locks outstanding on a recursive mutex, and a lock
|
||||
object, which even for a recursive mutex cannot have its lock()
|
||||
function called multiple times without first calling unlock().</p>
|
||||
|
||||
<p>Internally a lock count is maintained and the owning thread must
|
||||
unlock the mutex model the same number of times that it's locked it
|
||||
before the mutex model's state returns to unlocked. Since mutex
|
||||
models in <b>Boost.Threads</b> expose locking functionality only
|
||||
through lock concepts, a thread will always unlock a mutex model the
|
||||
same number of times that it locked it. This helps to eliminate a whole
|
||||
set of errors typically found in traditional C style thread APIs.</p>
|
||||
|
||||
<p>Classes <a href="recursive_mutex.html">recursive_mutex</a>, <a href=
|
||||
"recursive_mutex.html">recursive_try_mutex</a> and <a href=
|
||||
"recursive_mutex.html">recursive_timed_mutex</a> use this locking
|
||||
strategy.</p>
|
||||
|
||||
<h3><a name="CheckedStrategy">Checked</a></h3>
|
||||
|
||||
<p>With a checked locking strategy when a thread attempts to acquire a
|
||||
lock on the mutex model for which the thread already owns a lock, the
|
||||
operation will fail with some sort of error indication. Further,
|
||||
attempts by a thread to unlock a mutex that was not locked by the
|
||||
thread will also return some sort of error indication. In <b>
|
||||
Boost.Threads</b>, an exception of type <a href="lock_error.html">
|
||||
lock_error</a> would be thrown in these cases.</p>
|
||||
|
||||
<p><b>Boost.Threads</b> does not currently provide any mutex models
|
||||
that use this strategy.</p>
|
||||
|
||||
<h3><a name="UncheckedStrategy">Unchecked</a></h3>
|
||||
|
||||
<p>With an unchecked locking strategy when a thread attempts to acquire
|
||||
a lock on the mutex model for which the thread already owns a lock the
|
||||
operation will <a href="definitions.html#Deadlock">deadlock</a>. In
|
||||
general this locking strategy is less safe than a checked or recursive
|
||||
strategy, but it's also a faster strategy and so is employed by
|
||||
many libraries.</p>
|
||||
|
||||
<p><b>Boost.Threads</b> does not currently provide any mutex models
|
||||
that use this strategy.</p>
|
||||
|
||||
<h3><a name="UnspecifiedStrategy">Unspecified</a></h3>
|
||||
|
||||
<p>With an unspecified locking strategy, when a thread attempts to
|
||||
acquire a lock on a mutex model for which the thread already owns a
|
||||
lock the operation results in <b>undefined behavior</b>. When a mutex
|
||||
model has an unspecified locking strategy the programmer must assume
|
||||
that the mutex model instead uses an unchecked strategy.</p>
|
||||
|
||||
<p>In general a mutex model with an unspecified locking strategy is
|
||||
unsafe, and it requires programmer discipline to use the mutex model
|
||||
properly. However, this strategy allows an implementation to be as fast
|
||||
as possible with no restrictions on its implementation. This is
|
||||
especially true for portable implementations that wrap the native
|
||||
threading support of a platform. For this reason, the classes <a href=
|
||||
"mutex.html">mutex</a>, <a href="mutex.html">try_mutex</a> and <a href=
|
||||
"mutex.html">timed_mutex</a> use this locking strategy despite the lack
|
||||
of safety.</p>
|
||||
|
||||
<h2><a name="SchedulingPolicies">Scheduling Policies</a></h2>
|
||||
|
||||
<p>Every mutex model follows one of several scheduling policies. These
|
||||
policies define the semantics when the mutex model is unlocked and
|
||||
there is more than one thread waiting to acquire a lock. In other
|
||||
words, the policy defines which waiting thread shall acquire the
|
||||
lock.</p>
|
||||
|
||||
<h3><a name="FIFO">FIFO</a></h3>
|
||||
|
||||
<p>With a FIFO scheduling policy, threads waiting for the lock will
|
||||
acquire it in a first come first serve order (or First In First Out).
|
||||
This can help prevent a high priority thread from starving lower
|
||||
priority threads that are also waiting on the mutex lock.</p>
|
||||
|
||||
<h3><a name="Priority Driven">Priority Driven</a></h3>
|
||||
|
||||
<p>With a Priority Driven scheduling policy, the thread with the
|
||||
highest priority acquires the lock. Note that this means that
|
||||
low-priority threads may never acquire the lock if the mutex model has
|
||||
high contention and there is always at least one high-priority thread
|
||||
waiting. This is known as thread starvation. When multiple threads of
|
||||
the same priority are waiting on the mutex lock one of the other
|
||||
scheduling priorities will determine which thread shall acquire the
|
||||
lock.</p>
|
||||
|
||||
<h3><a name="UndefinedScheduling">Undefined</a></h3>
|
||||
|
||||
<p>Threads acquire the lock in no particular order. Users should assume
|
||||
that low-priority threads may wait indefinitely, and that threads of
|
||||
the same priority acquire the lock in essentially random order.</p>
|
||||
|
||||
<h3><a name="UnspecifiedScheduling">Unspecified</a></h3>
|
||||
|
||||
<p>The mutex model does not specify which scheduling policy is used.
|
||||
The programmer must assume that an undefined scheduling policy is used.
|
||||
In order to ensure portability, all <b>Boost.Threads</b> mutex models
|
||||
use an unspecified scheduling policy.</p>
|
||||
|
||||
<h2>Concept <a name="Requirements">Requirements</a></h2>
|
||||
|
||||
<h3><a name="Mutex">Mutex</a> Concept</h3>
|
||||
|
||||
<p>A Mutex object has two states: locked and unlocked. Mutex object
|
||||
state can only be determined by an object meeting the <a href=
|
||||
"lock_concept.html#ScopedLock">ScopedLock</a> requirements and
|
||||
constructed for the Mutex object.</p>
|
||||
|
||||
<p>A Mutex is <a href="../../utility/utility.htm#Class noncopyable">
|
||||
noncopyable</a>.</p>
|
||||
|
||||
<p>For a Mutex type M and an object m of that type, the following
|
||||
expressions must be well-formed and have the indicated effects.</p>
|
||||
|
||||
<table summary="Mutex expressions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><code>M m;</code></td>
|
||||
|
||||
<td>Constructs a mutex object m. Post-condition: m is
|
||||
unlocked.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><code>(&m)->~M();</code></td>
|
||||
|
||||
<td>Precondition: m is unlocked. Destroys a mutex object
|
||||
m.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><code>M::scoped_lock</code></td>
|
||||
|
||||
<td>A type meeting the <a href="lock_concept.html#ScopedLock">
|
||||
ScopedLock</a> requirements.</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<h3><a name="TryMutex">TryMutex</a> Concept</h3>
|
||||
|
||||
<p>A TryMutex must meet the <a href="#Mutex">Mutex</a> requirements. In
|
||||
addition, for a TryMutex type M and an object m of that type, the
|
||||
following expressions must be well-formed and have the indicated
|
||||
effects.</p>
|
||||
|
||||
<table summary="TryMutex expressions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><code>M::scoped_try_lock</code></td>
|
||||
|
||||
<td>A type meeting the <a href=
|
||||
"lock_concept.html#ScopedTryLock">ScopedTryLock</a>
|
||||
requirements.</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<h3><a name="TimedMutex">TimedMutex</a> Concept</h3>
|
||||
|
||||
<p>A TimedMutex must meet the <a href="#TryMutex">TryMutex</a>
|
||||
requirements. In addition, for a TimedMutex type M and an object m of
|
||||
that type, the following expressions must be well-formed and have the
|
||||
indicated effects.</p>
|
||||
|
||||
<table summary="TimedMutex expressions" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Expression</b></td>
|
||||
|
||||
<td><b>Effects</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td><code>M::scoped_timed_lock</code></td>
|
||||
|
||||
<td>A type meeting the <a href=
|
||||
"lock_concept.html#ScopedTimedLock">ScopedTimedLock</a>
|
||||
requirements.</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<h2><a name="Models">Models</a></h2>
|
||||
|
||||
<p><b>Boost.Threads</b> currently supplies six classes which model
|
||||
mutex concepts.</p>
|
||||
|
||||
<table summary="Mutex concept classes" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Concept</b></td>
|
||||
|
||||
<td><b>Refines</b></td>
|
||||
|
||||
<td><b>Classes Modeling the Concept</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><a href="#Mutex">Mutex</a></td>
|
||||
|
||||
<td valign="top"> </td>
|
||||
|
||||
<td><a href="mutex.html">mutex</a><br>
|
||||
<a href="recursive_mutex.html">recursive_mutex</a></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><a href="#TryMutex">TryMutex</a></td>
|
||||
|
||||
<td valign="top"><a href="#Mutex">Mutex</a></td>
|
||||
|
||||
<td><a href="mutex.html">try_mutex<br>
|
||||
</a> <a href="recursive_mutex.html">recursive_try_mutex</a>
|
||||
</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><a href="#TimedMutex">TimedMutex</a></td>
|
||||
|
||||
<td valign="top"><a href="#TryMutex">TryMutex</a></td>
|
||||
|
||||
<td><a href="mutex.html">timed_mutex<br>
|
||||
</a> <a href="recursive_mutex.html">
|
||||
recursive_timed_mutex</a></td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
@@ -1,90 +0,0 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Header <boost/thread/once.hpp></title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Header <<a href="../../../boost/thread/once.hpp">boost/thread/once.hpp</a>></h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<h2>Contents</h2>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#macros">Macros</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#macro-BOOST_ONCE_INIT">BOOST_ONCE_INIT</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#types">Types</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#type-once_flag">once_flag</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#functions">Functions</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#function-call_once">call_once</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#examples">Example(s)</a></dt>
|
||||
</dl>
|
||||
<hr>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>Include the header <<a href="../../../boost/thread/once.hpp">boost/thread/once.hpp</a>>
|
||||
to define the <code>call_once</code> function, <code>once_flag</code> type and
|
||||
<code>BOOST_ONCE_INIT</code> constant.</p>
|
||||
<p>The <code>call_once</code> function and <code>once_flag</code> type (statically
|
||||
initialized to <code>BOOST_ONCE_INIT</code>) can be used to run a routine exactly
|
||||
once. This can be used to initialize data in a <a href="definitions.html#Thread-safe">
|
||||
thread-safe</a> manner.</p>
|
||||
<h2><a name="macros"></a>Macros</h2>
|
||||
<pre>
|
||||
<a name="macro-BOOST_ONCE_INIT"></a>#define BOOST_ONCE_INIT <i>implementation defined</i>
|
||||
</pre>
|
||||
<p>This is a constant value used to initialize <code>once_flag</code> instances
|
||||
to indicate that the logically associated routine has not been run yet.</p>
|
||||
<h2><a name="types"></a>Types</h2>
|
||||
<pre>
|
||||
<a name="type-once_flag"></a>typedef <i>implementation defined</i> once_flag;
|
||||
</pre>
|
||||
<p>This implementation defined type is used as a flag to insure a routine is called
|
||||
only once. Instances of this type should be statically initialized to <code>BOOST_ONCE_INIT</code>.</p>
|
||||
<h2><a name="functions"></a>Functions</h2>
|
||||
<pre>
|
||||
<a name="function-call_once"></a>void call_once(void (*func)(), once_flag& flag);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> The function <code>func</code> shall not throw exceptions.</dt>
|
||||
<dt><b>Effects:</b> As if (in an atomic fashion):
|
||||
<pre>
|
||||
if (flag == BOOST_ONCE_INIT)
|
||||
func();
|
||||
</pre>
|
||||
</dt>
|
||||
<dt><b>Postconditions:</b> <code>flag != BOOST_ONCE_INIT</code></dt>
|
||||
</dl>
|
||||
<h2><a name="examples"></a>Example(s)</h2>
|
||||
<p><a href="../example/once.cpp">libs/thread/example/once.cpp</a></p>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
@@ -1,172 +1,224 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Overview</title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Overview</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<dl class="index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#dangers">Dangers</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="#testing-debugging">Testing and debugging considerations</a></dt>
|
||||
<dt><a href="#head-start">Getting a head start</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#library">C++ Standard Library usage in multithreaded programs</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="#runtime-libraries">Runtime libraries</a></dt>
|
||||
<dt><a href="#non-thread-safe-functions">Potentially non-thread-safe functions</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#common-requirements">Common requirements for all Boost.Threads
|
||||
components</a></dt>
|
||||
<dl class="index">
|
||||
<dt><a href="#exceptions">Exceptions</a></dt>
|
||||
<dt><a href="#non-copyable">NonCopyable requirement</a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>Boost.Threads allows C++ programs to execute as multiple, asynchronous, independent,
|
||||
threads-of-execution. Each thread has its own machine state including program
|
||||
instruction counter and registers. Programs which execute as multiple threads
|
||||
are called multithreaded programs to distinguish them from traditional single-threaded
|
||||
programs. <a href="definitions.html">Definitions</a> gives a more complete description
|
||||
of the multithreading execution environment.</p>
|
||||
<p>Multithreading provides several advantages:</p>
|
||||
<ul>
|
||||
<li>Programs which would otherwise block waiting for some external event can
|
||||
continue to respond if the blocking operation is placed in a separate thread.
|
||||
Multithreading is usually an absolute requirement for these programs.</li>
|
||||
</ul>
|
||||
<ul>
|
||||
<li>Well-designed multithreaded programs may execute faster than single-threaded
|
||||
programs, particularly on multiprocessor hardware. Note, however, that poorly-designed
|
||||
multithreaded programs are often slower that single-threaded programs.</li>
|
||||
</ul>
|
||||
<ul>
|
||||
<li>Some program designs may be easier to formulate using a multithreaded approach.
|
||||
After all, the real world is asynchronous!</li>
|
||||
</ul>
|
||||
<h2><a name="dangers"></a>Dangers</h2>
|
||||
<p>Beyond the errors which can occur in single-threaded programs, multithreaded
|
||||
programs are subject to additional errors:</p>
|
||||
<ul>
|
||||
<li><a href="definitions.html#definition-race-condition">Race conditions</a>.</li>
|
||||
<li><a href="definitions.html#definition-deadlock">Deadlock</a> (sometimes called
|
||||
"deadly embrace")</li>
|
||||
<li><a href="definitions.html#definition-priority-failure">Priority failures</a>
|
||||
(priority inversion, infinite overtaking, starvation, etc.)</li>
|
||||
</ul>
|
||||
<p>Every multithreaded program must be designed carefully to avoid race conditions,
|
||||
priority failures and deadlock. These aren't rare or exotic failures - they
|
||||
are virtually guaranteed to occur unless multithreaded code is designed to avoid
|
||||
them. Priority failures are somewhat less common, but are nonetheless serious.</p>
|
||||
<p>The <a href="introduction.html">Boost.Threads design</a> attempts to minimize
|
||||
these errors, but they will still occur unless the programmer proactively designs
|
||||
to avoid them.</p>
|
||||
<h3><a name="testing-debugging"></a>Testing and debugging considerations</h3>
|
||||
<p>Multithreaded programs are non-deterministic. In other words, the same program
|
||||
with the same input data may follow different execution paths each time it is
|
||||
invoked. That can make testing and debugging a nightmare:</p>
|
||||
<ul>
|
||||
<li>Failures are often not repeatable.</li>
|
||||
<li>Probe effect causes debuggers to produce very different results from non-debug
|
||||
uses.</li>
|
||||
<li>Debuggers require special support to show thread state.</li>
|
||||
<li>Tests on a single processor system may give no indication of serious errors
|
||||
which would appear on multiprocessor systems, and visa versa. Thus test cases
|
||||
should include a varying number of processors.</li>
|
||||
<li>For programs which create a varying number of threads according to workload,
|
||||
tests which don't span the full range of possibilities may miss serious
|
||||
errors.</li>
|
||||
</ul>
|
||||
<h3><a name="head-start"></a>Getting a head start</h3>
|
||||
<p>Although it might appear that multithreaded programs are inherently unreliable,
|
||||
many reliable multithreaded programs do exist. Multithreading techniques are
|
||||
known which lead to reliable programs.</p>
|
||||
<p>Design patterns for reliable multithreaded programs, including the important
|
||||
<i>monitor</i> pattern, are presented in <cite> Pattern-Oriented Software Architecture
|
||||
Volume 2 - Patterns for Concurrent and Networked Objects</cite> [<a href=
|
||||
"bibliography.html#Schmidt-00">Schmidt 00</a>]. Many important multithreading
|
||||
programming considerations (independent of threading library) are discussed
|
||||
in <cite>Programming with POSIX Threads</cite> [<a href="bibliography.html#Butenhof-97">Butenhof
|
||||
97</a>].</p>
|
||||
<p>Doing some reading before attempting multithreaded designs will give you a
|
||||
head start toward reliable multithreaded programs.</p>
|
||||
<h2><a name="library"></a>C++ Standard Library usage in multithreaded programs</h2>
|
||||
<h3><a name="runtime-libraries"></a>Runtime libraries</h3>
|
||||
<p><b>Warning:</b> Multithreaded programs such as those using <b> Boost.Threads</b>
|
||||
must link to <a href="definitions.html#Thread-safe"> thread-safe</a> versions
|
||||
of all runtime libraries used by the program, including the runtime library
|
||||
for the C++ Standard Library. Otherwise
|
||||
<a href="definitions.html#definition-race-condition">race
|
||||
conditions</a> will occur when multiple threads simultaneously execute runtime
|
||||
library functions for <i>new</i>, <i>delete</i>, or other language features
|
||||
which imply shared state.</p>
|
||||
<h3><a name="non-thread-safe-functions"></a>Potentially non-thread-safe functions</h3>
|
||||
<p>Certain C++ Standard Library functions inherited from C are particular problems
|
||||
because they hold internal state between calls:</p>
|
||||
<ul>
|
||||
<li>rand</li>
|
||||
<li>strtok</li>
|
||||
<li>asctime</li>
|
||||
<li>ctime</li>
|
||||
<li>gmtime</li>
|
||||
<li>localtime</li>
|
||||
</ul>
|
||||
<p>It is possible to write thread-safe implementations of these by using <a href="tss.html#class-thread_specific_ptr">thread-specific
|
||||
storage</a>, and several C++ compiler vendors do just that. The technique is
|
||||
well-know and is explained in [<a href=
|
||||
"bibliography.html#Butenhof-97">Buttenhof 97</a>].</p>
|
||||
<p>But at least one vendor (HP-UX) does not provide thread-safe implementations
|
||||
of the above functions in their otherwise thread-safe runtime library. Instead
|
||||
they provide replacement functions with different names and arguments.</p>
|
||||
<p><b>Recommendation:</b> For the most portable, yet thread-safe code, use Boost
|
||||
replacements for the problem functions. See the <a href=
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=windows-1252">
|
||||
<meta name="GENERATOR" content="Microsoft FrontPage 4.0">
|
||||
<meta name="ProgId" content="FrontPage.Editor.Document">
|
||||
|
||||
<title>Boost.Threads Overview</title>
|
||||
</head>
|
||||
|
||||
<body>
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img height="86" alt="C++ Boost" src=
|
||||
"../../../c++boost.gif" width="277"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">Overview</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Dangers">Dangers</a><br>
|
||||
<a href="#Library">C++ Standard Library usage</a><br>
|
||||
<a href="#Common">Common requirements</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>Boost.Threads allows C++ programs to execute as multiple,
|
||||
asynchronous, independent, threads-of-execution. Each thread has its
|
||||
own machine state including program instruction counter and registers.
|
||||
Programs which execute as multiple threads are called multi-threaded
|
||||
programs to distinguish them from traditional single-threaded programs.
|
||||
<a href="definitions.html">Definitions</a> gives a more complete
|
||||
description of the multi-threading execution environment.</p>
|
||||
|
||||
<p>Multi-threading provides several advantages:</p>
|
||||
|
||||
<ul>
|
||||
<li>Programs which would otherwise block waiting for some external
|
||||
event can continue to respond if the blocking operation is placed
|
||||
in a separate thread. Multi-threading is usually an absolute
|
||||
requirement for these programs.</li>
|
||||
</ul>
|
||||
|
||||
<ul>
|
||||
<li>Well-designed multi-threaded programs may execute faster than
|
||||
single-threaded programs, particularly on multi-processor hardware.
|
||||
Note, however, that poorly-designed multi-threaded programs are
|
||||
often slower that single-threaded programs.</li>
|
||||
</ul>
|
||||
|
||||
<ul>
|
||||
<li>Some program designs may be easier to formulate using a
|
||||
multi-threaded approach. After all, the real world is
|
||||
asynchronous!</li>
|
||||
</ul>
|
||||
|
||||
<h2><a name="Dangers">Dangers</a></h2>
|
||||
|
||||
<p>Beyond the errors which can occur in single-threaded programs,
|
||||
multi-threaded programs are subject to additional errors:</p>
|
||||
|
||||
<ul>
|
||||
<li><a href="definitions.html#Race condition">Race
|
||||
conditions</a>.</li>
|
||||
|
||||
<li><a href="definitions.html#Deadlock">Deadlock</a> (sometimes
|
||||
called "deadly embrace")</li>
|
||||
|
||||
<li><a href="definitions.html#Priority failure">Priority
|
||||
failures</a> (priority inversion, infinite overtaking, starvation,
|
||||
etc.)</li>
|
||||
</ul>
|
||||
|
||||
<p>Every multi-threaded program must be designed carefully to avoid
|
||||
race conditions and deadlock. These aren't rare or exotic failures
|
||||
- they are virtually guaranteed to occur unless multi-threaded code is
|
||||
designed to avoid them. Priority failures are somewhat less common, but
|
||||
are none-the-less serious.</p>
|
||||
|
||||
<p>The <a href="introduction.html">Boost.Threads design</a> attempts to
|
||||
minimize these errors, but they will still occur unless the programmer
|
||||
proactively designs to avoid them.</p>
|
||||
|
||||
<h3>Testing and debugging considerations</h3>
|
||||
|
||||
<p>Multi-threaded programs are non-deterministic. In other words, the
|
||||
same program with the same input data may follow different execution
|
||||
paths each time it is invoked. That can make testing and debugging a
|
||||
nightmare:</p>
|
||||
|
||||
<ul>
|
||||
<li>Failures are often not repeatable.</li>
|
||||
|
||||
<li>Probe effect causes debuggers to produce very different results
|
||||
from non-debug uses.</li>
|
||||
|
||||
<li>Debuggers require special support to show thread state.</li>
|
||||
|
||||
<li>Tests on a single processor system may give no indication of
|
||||
serious errors which would appear on multiprocessor systems, and
|
||||
visa versa. Thus test cases should include a varying number of
|
||||
processors.</li>
|
||||
|
||||
<li>For programs which create a varying number of threads according
|
||||
to workload, tests which don't span the full range of
|
||||
possibilities may miss serious errors.</li>
|
||||
</ul>
|
||||
|
||||
<h3>Getting a head start</h3>
|
||||
|
||||
<p>Although it might appear that multi-threaded programs are inherently
|
||||
unreliable, many reliable multi-threaded programs do exist.
|
||||
Multi-threading techniques are known which lead to reliable
|
||||
programs.</p>
|
||||
|
||||
<p>Design patterns for reliable multi-threaded programs, including the
|
||||
important <i>monitor</i> pattern, are presented in <cite>
|
||||
Pattern-Oriented Software Architecture Volume 2 - Patterns for
|
||||
Concurrent and Networked Objects</cite> [<a href=
|
||||
"bibliography.html#Schmidt-00">Schmidt 00</a>]. Many important
|
||||
multi-threading programming considerations (independent of threading
|
||||
library) are discussed in <cite>Programming with POSIX Threads</cite>
|
||||
[<a href="bibliography.html#Butenhof-97">Butenhof 97</a>].</p>
|
||||
|
||||
<p>Doing some reading before attempting multi-threaded designs will give
|
||||
you a head start toward reliable multi-threaded programs.</p>
|
||||
|
||||
<h2><a name="Library">C++ Standard Library usage in multi-threaded
|
||||
programs</a></h2>
|
||||
|
||||
<h3>Runtime libraries</h3>
|
||||
|
||||
<p><b>Warning:</b> Multi-threaded programs such as those using <b>
|
||||
Boost.Threads</b> must link to <a href="definitions.html#Thread-safe">
|
||||
thread-safe</a> versions of all runtime libraries used by the program,
|
||||
including the runtime library for the C++ Standard Library. Otherwise
|
||||
<a href="definitions.html#Race condition">race conditions</a> will
|
||||
occur when multiple threads simultaneously execute runtime library
|
||||
functions for <i>new</i>, <i>delete</i>, or other language features
|
||||
which imply shared state.</p>
|
||||
|
||||
<h3>Potentially non-thread-safe functions</h3>
|
||||
|
||||
<p>Certain C++ Standard Library functions inherited from C are
|
||||
particular problems because they hold internal state between calls:</p>
|
||||
|
||||
<ul>
|
||||
<li>rand</li>
|
||||
|
||||
<li>strtok</li>
|
||||
|
||||
<li>asctime</li>
|
||||
|
||||
<li>ctime</li>
|
||||
|
||||
<li>gmtime</li>
|
||||
|
||||
<li>localtime</li>
|
||||
</ul>
|
||||
|
||||
<p>It is possible to write thread-safe implementations of these by
|
||||
using <a href="thread_specific_ptr.html">thread-specific storage</a>,
|
||||
and several C++ compiler vendors do just that. The technique is
|
||||
well-know and is explained in [<a href=
|
||||
"bibliography.html#Butenhof-97">Buttenhof-97</a>].</p>
|
||||
|
||||
<p>But at least one vendor (HP-UX) does not provide thread-safe
|
||||
implementations of the above functions in their otherwise thread-safe
|
||||
runtime library. Instead they provide replacement functions with
|
||||
different names and arguments.</p>
|
||||
|
||||
<p><b>Recommendation:</b> For the most portable, yet thread-safe code,
|
||||
use Boost replacements for the problem functions. See the <a href=
|
||||
"../../random/index.html">Boost Random Number Library</a> and <a href=
|
||||
"../../tokenizer/index.htm">Boost Tokenizer Library</a>.</p>
|
||||
<h2><a name="common-gaurantees"></a>Common guarantees for all Boost.Threads components</h2>
|
||||
<h3><a name="exceptions"></a>Exceptions</h3>
|
||||
<p><b>Boost.Threads</b> destructors never throw exceptions. Unless otherwise specified,
|
||||
other <b>Boost.Threads</b> functions that do not have an exception-specification
|
||||
may throw implementation-defined exceptions.</p>
|
||||
<p>In particular, <b>Boost.Threads</b> reports failure to allocate storage by
|
||||
throwing an exception of type std::bad_alloc, or a class derived from std::bad_alloc,
|
||||
failure to obtain thread resources other than memory by throwing an exception
|
||||
of type <a href="exceptions.html#class-thread_resource_error">boost::thread_resource_error</a>,
|
||||
and certain lock related failures by throwing an exception of type <a href="exceptions.html#class-lock_error">boost::lock_error</a></p>
|
||||
<p><b>Rationale:</b> Follows the C++ Standard Library practice of allowing all
|
||||
functions except destructors or other specified functions to throw exceptions
|
||||
on errors.</p>
|
||||
<h3><a name="non-copyable"></a>NonCopyable requirement</h3>
|
||||
<p><b>Boost.Threads</b> classes documented as meeting the NonCopyable requirement
|
||||
disallow copy construction and copy assignment. For the sake of exposition,
|
||||
the synopsis of such classes show private derivation from <a href="../../utility/utility.htm">
|
||||
boost::noncopyable</a>. Users should not depend on this derivation, however,
|
||||
as implementations are free to meet the NonCopyable requirement in other ways.</p>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->09 January, 2003<!--webbot bot="Timestamp" endspan i-checksum="38582" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
<h2><a name="Common">Common</a> requirements for all Boost.Threads
|
||||
components</h2>
|
||||
|
||||
<h3>Exceptions</h3>
|
||||
|
||||
<p><b>Boost.Threads</b> destructors never throw exceptions. Unless
|
||||
otherwise specified, other <b>Boost.Threads</b> functions that do not
|
||||
have an exception-specification may throw implementation-defined
|
||||
exceptions.</p>
|
||||
|
||||
<p>In particular, <b>Boost.Threads</b> reports failure to allocate
|
||||
storage by throwing an exception of type std::bad_alloc, or a class
|
||||
derived from std::bad_alloc, failure to obtain thread resources other
|
||||
than memory by throwing an exception of type <a href=
|
||||
"thread_resource_error.html">boost::thread_resource_error</a>, and
|
||||
certain lock related failures by throwing an exception of type <a href=
|
||||
"lock_error.html">boost::lock_error</a></p>
|
||||
|
||||
<p><b>Rationale:</b> Follows the C++ Standard Library practice of
|
||||
allowing all functions except destructors or other specified functions
|
||||
to throw exceptions on errors.</p>
|
||||
|
||||
<h3><a name="NonCopyable">NonCopyable</a> requirement</h3>
|
||||
|
||||
<p><b>Boost.Threads</b> classes documented as meeting the NonCopyable
|
||||
requirement disallow copy construction and copy assignment. For the
|
||||
sake of exposition, the synopsis of such classes show private
|
||||
derivation from <a href="../../utility/utility.htm">
|
||||
boost::noncopyable</a>. Users should not depend on this derivation,
|
||||
however, as implementations are free to meet the NonCopyable
|
||||
requirement in other ways.</p>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p>© Copyright 2001 Beman Dawes</p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
@@ -1,170 +1,215 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Rationale</title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Rationale</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<dl class="index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#library">Rationale for the Creation of <b>Boost.Threads</b></a></dt>
|
||||
<dt><a href="#primitives">Rationale for the Low Level Primitives Supported in
|
||||
<b>Boost.Threads</b></a></dt>
|
||||
<dt><a href="#lock_objects">Rationale for the Lock Design</a></dt>
|
||||
<dt><a href="#non-copyable">Rationale for NonCopyable Thread Type</a></dt>
|
||||
<dt><a href="#events">Rationale for not providing <i>Event Variables</i></a></dt>
|
||||
</dl>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>This page explains the rationale behind various design decisions in the <b>Boost.Threads</b>
|
||||
library. Having the rationale documented here should explain how we arrived
|
||||
at the current design as well as prevent future rehashing of discussions and
|
||||
thought processes that have already occurred. It can also give users a lot of
|
||||
insight into the design process required for this library.</p>
|
||||
<h2><a name="library"></a>Rationale for the Creation of <b>Boost.Threads</b></h2>
|
||||
<p>Processes often have a degree of "potential parallelism" and it can
|
||||
often be more intuitive to design systems with this in mind. Further, these
|
||||
parallel processes can result in more responsive programs. The benefits for
|
||||
multithreaded programming are quite well known to most modern programmers, yet
|
||||
the C++ language doesn't directly support this concept.</p>
|
||||
<p>Many platforms support multithreaded programming despite the fact that the
|
||||
language doesn't support it. They do this through external libraries, which
|
||||
are, unfortunately, platform specific. POSIX has tried to address this problem
|
||||
through the standardization of a "pthread" library. However, this
|
||||
is a standard only on POSIX platforms, so its portability is limited.</p>
|
||||
<p>Another problem with POSIX and other platform specific thread libraries is
|
||||
that they are almost universally C based libraries. This leaves several C++
|
||||
specific issues unresolved, such as what happens when an exception is thrown
|
||||
in a thread. Further, there are some C++ concepts, such as destructors, that
|
||||
can make usage much easier than what's available in a C library.</p>
|
||||
<p>What's truly needed is C++ language support for threads. However, the C++
|
||||
standards committee needs existing practice or a good proposal as a starting
|
||||
point for adding this to the standard.</p>
|
||||
<p>The <b>Boost.Threads</b> library was developed to provide a C++ developer with
|
||||
a portable interface for writing multithreaded programs on numerous platforms.
|
||||
There's a hope that the library can be the basis for a more detailed proposal
|
||||
for the C++ standards committee to consider for inclusion in the next C++ standard.</p>
|
||||
<h2><a name="primitives"></a>Rationale for the Low Level Primitives Supported
|
||||
in <b>Boost.Threads</b></h2>
|
||||
<p>The <b>Boost.Threads</b> library supplies a set of low level primitives for
|
||||
writing multithreaded programs, such as mutexes and condition variables. In
|
||||
fact, the first release of <b>Boost.Threads</b> supports only these low level
|
||||
primitives. However, computer science research has shown that use of these primitives
|
||||
is difficult since it's difficult to mathematically prove that a usage pattern
|
||||
is correct, meaning it doesn't result in race conditions or deadlocks. There
|
||||
are several algebras (such as CSP, CCS and Join calculus) that have been developed
|
||||
to help write provably correct parallel processes. In order to prove the correctness
|
||||
these processes must be coded using higher level abstractions. So why does <b>Boost.Threads</b>
|
||||
support the lower level concepts?</p>
|
||||
<p>The reason is simple: the higher level concepts need to be implemented using
|
||||
at least some of the lower level concepts. So having portable lower level concepts
|
||||
makes it easier to develop the higher level concepts and will allow researchers
|
||||
to experiment with various techniques.</p>
|
||||
<p>Beyond this theoretical application of higher level concepts, however, the
|
||||
fact remains that many multithreaded programs are written using only the lower
|
||||
level concepts, so they are useful in and of themselves, even if it's hard
|
||||
to prove that their usage is correct. Since many users will be familiar with
|
||||
these lower level concepts but be unfamiliar with any of the higher level concepts
|
||||
there's also an argument for accessibility.</p>
|
||||
<h2><a name="lock_objects"></a>Rationale for the Lock Design</h2>
|
||||
<p>Programmers who are used to multithreaded programming issues will quickly note
|
||||
that the Boost.Thread's design for mutex lock concepts is not <a href="definitions.html#Thread-safe">thread-safe</a>
|
||||
(this is clearly documented as well). At first this may seem like a serious
|
||||
design flaw. Why have a multithreading primitive that's not thread-safe
|
||||
itself?</p>
|
||||
<p>A lock object is not a synchronization primitive. A lock object's sole
|
||||
responsibility is to ensure that a mutex is both locked and unlocked in a manner
|
||||
that won't result in the common error of locking a mutex and then forgetting
|
||||
to unlock it. This means that instances of a lock object are only going to be
|
||||
created, at least in theory, within block scope and won't be shared between
|
||||
threads. Only the mutex objects will be created outside of block scope and/or
|
||||
shared between threads. Though it's possible to create a lock object outside
|
||||
of block scope and to share it between threads to do so would not be a typical
|
||||
usage (in fact, to do so would likely be an error). Nor are there any cases
|
||||
when such usage would be required.</p>
|
||||
<p>Lock objects must maintain some state information. In order to allow a program
|
||||
to determine if a try_lock or timed_lock was successful the lock object must
|
||||
retain state indicating the success or failure of the call made in its constructor.
|
||||
If a lock object were to have such state and remain thread-safe it would need
|
||||
to synchronize access to the state information which would result in roughly
|
||||
doubling the time of most operations. Worse, since checking the state can occur
|
||||
only by a call after construction we'd have a race condition if the lock
|
||||
object were shared between threads.</p>
|
||||
<p>So, to avoid the overhead of synchronizing access to the state information
|
||||
and to avoid the race condition the <b>Boost.Threads</b> library simply does
|
||||
nothing to make lock objects thread-safe. Instead, sharing a lock object between
|
||||
threads results in undefined behavior. Since the only proper usage of lock objects
|
||||
is within block scope this isn't a problem, and so long as the lock object
|
||||
is properly used there's no danger of any multithreading issues.</p>
|
||||
<h2><a name="non-copyable"></a>Rationale for NonCopyable Thread Type</h2>
|
||||
<p>Programmers who are used to C libraries for multithreaded programming are likely
|
||||
to wonder why <b>Boost.Threads</b> uses a noncopyable design for <a href="thread.html">boost::thread</a>.
|
||||
After all, the C thread types are copyable, and you often have a need for copying
|
||||
them within user code. However, careful comparison of C designs to C++ designs
|
||||
shows a flaw in this logic.</p>
|
||||
<p>All C types are copyable. It is, in fact, not possible to make a noncopyable
|
||||
type in C. For this reason types that represent system resources in C are often
|
||||
designed to behave very similarly to a pointer to dynamic memory. There's
|
||||
an API for acquiring the resource and an API for releasing the resources. For
|
||||
memory we have pointers as the type and alloc/free for the acquisition and release
|
||||
APIs. For files we have FILE* as the type and fopen/fclose for the acquisition
|
||||
and release APIs. You can freely copy instances of the types but must manually
|
||||
manage the lifetime of the actual resource through the acquisition and release
|
||||
APIs.</p>
|
||||
<p>C++ designs recognize that the acquisition and release APIs are error prone
|
||||
and try to eliminate possible errors by acquiring the resource in the constructor
|
||||
and releasing it in the destructor. The best example of such a design is the
|
||||
std::iostream set of classes which can represent the same resource as the FILE*
|
||||
type in C. A file is opened in the std::fstream's constructor and closed
|
||||
in its destructor. However, if an iostream were copyable it could lead to a
|
||||
file being closed twice, an obvious error, so the std::iostream types are noncopyable
|
||||
by design. This is the same design used by boost::thread, which is a simple
|
||||
and easy to understand design that's consistent with other C++ standard
|
||||
types.</p>
|
||||
<p>During the design of boost::thread it was pointed out that it would be possible
|
||||
to allow it to be a copyable type if some form of "reference management"
|
||||
were used, such as ref-counting or ref-lists, and many argued for a boost::thread_ref
|
||||
design instead. The reasoning was that copying "thread" objects was
|
||||
a typical need in the C libraries, and so presumably would be in the C++ libraries
|
||||
as well. It was also thought that implementations could provide more efficient
|
||||
reference management than wrappers (such as boost::shared_ptr) around a noncopyable
|
||||
thread concept. Analysis of whether or not these arguments would hold true doesn't
|
||||
appear to bear them out. To illustrate the analysis we'll first provide
|
||||
pseudo-code illustrating the six typical usage patterns of a thread object.</p>
|
||||
<h3>1. Simple creation of a thread.</h3>
|
||||
<pre>void foo()
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
|
||||
<title>Boost.Threads, rationale</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#ffffff" link="#0000ff" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img height="86" alt="C++ Boost" src=
|
||||
"../../../c++boost.gif" width="277"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">Rationale</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p>This page explains the rationale behind various design decisions in
|
||||
the <b>Boost.Threads</b> library. Having the rationale documented here
|
||||
should explain how we arrived at the current design as well as prevent
|
||||
future rehashing of discussions and thought processes that have already
|
||||
occurred. It can also give users a lot of insight into the design
|
||||
process required for this library.</p>
|
||||
|
||||
<h2><a name="library">Rationale for the Creation of
|
||||
Boost.Threads</a></h2>
|
||||
|
||||
<p>Processes often have a degree of "potential parallelism"
|
||||
and it can often be more intuitive to design systems with this in mind.
|
||||
Further, these parallel processes can result in more responsive
|
||||
programs. The benefits for multi-threaded programming are quite well
|
||||
known to most modern programmers, yet the C++ language doesn't
|
||||
directly support this concept.</p>
|
||||
|
||||
<p>Many platforms support multi-threaded programming despite the fact
|
||||
that the language doesn't support it. They do this through external
|
||||
libraries, which are, unfortunately, platform specific. POSIX has tried
|
||||
to address this problem through the standardization of a
|
||||
"pthread" library. However, this is a standard only on POSIX
|
||||
platforms, so its portability is limited.</p>
|
||||
|
||||
<p>Another problem with POSIX and other platform specific thread
|
||||
libraries is that they are almost universally C based libraries. This
|
||||
leaves several C++ specific issues unresolved, such as what happens
|
||||
when an exception is thrown in a thread. Further, there are some C++
|
||||
concepts, such as destructors, that can make usage much easier than
|
||||
what's available in a C library.</p>
|
||||
|
||||
<p>What's truly needed is C++ language support for threads.
|
||||
However, the C++ standards committee needs existing practice or a good
|
||||
proposal as a starting point for adding this to the standard.</p>
|
||||
|
||||
<p>The Boost.Threads library was developed to provide a C++ developer
|
||||
with a portable interface for writing multi-threaded programs on
|
||||
numerous platforms. There's a hope that the library can be the
|
||||
basis for a more detailed proposal for the C++ standards committee to
|
||||
consider for inclusion in the next C++ standard.</p>
|
||||
|
||||
<h2><a name="primitives">Rationale for the Low Level Primitives
|
||||
Supported in Boost.Threads</a></h2>
|
||||
|
||||
<p>The Boost.Threads library supplies a set of low level primitives for
|
||||
writing multi-threaded programs, such as mutexes and condition variables.
|
||||
In fact, the first release of Boost.Threads supports only these low level
|
||||
primitives. However, computer science research has shown that use of these
|
||||
primitives is difficult since there's no way to mathematically prove
|
||||
that a usage pattern is correct, meaning it doesn't result in race
|
||||
conditions or deadlocks. There are several algebras (such as CSP, CCS and
|
||||
Join calculus) that have been developed to help write provably correct
|
||||
parallel processes. In order to prove the correctness these processes must
|
||||
be coded using higher level abstractions. So why does Boost.Threads support
|
||||
the lower level concepts?</p>
|
||||
|
||||
<p>The reason is simple: the higher level concepts need to be
|
||||
implemented using at least some of the lower level concepts. So having
|
||||
portable lower level concepts makes it easier to develop the higher
|
||||
level concepts and will allow researchers to experiment with various
|
||||
techniques.</p>
|
||||
|
||||
<p>Beyond this theoretical application of higher level concepts,
|
||||
however, the fact remains that many multi-threaded programs are written
|
||||
using only the lower level concepts, so they are useful in and of
|
||||
themselves, even if it's hard to prove that their usage is correct.
|
||||
Since many users will be familiar with these lower level concepts but
|
||||
be unfamiliar with any of the higher level concepts there's also an
|
||||
argument for accessibility.</p>
|
||||
|
||||
<h2><a name="lock_objects">Rationale for the Lock Design</a></h2>
|
||||
|
||||
<p>Programmers who are used to multi-threaded programming issues will
|
||||
quickly note that the Boost.Thread's design for mutex lock concepts
|
||||
is not <a href="definitions.html#Thread-safe">thread-safe</a> (this is
|
||||
clearly documented as well). At first this may seem like a serious
|
||||
design flaw. Why have a multi-threading primitive that's not
|
||||
thread-safe itself?</p>
|
||||
|
||||
<p>A lock object is not a synchronization primitive. A lock
|
||||
object's sole responsibility is to ensure that a mutex is both
|
||||
locked and unlocked in a manner that won't result in the common
|
||||
error of locking a mutex and then forgetting to unlock it. This means
|
||||
that instances of a lock object are only going to be created, at least
|
||||
in theory, within block scope and won't be shared between threads.
|
||||
Only the mutex objects will be created outside of block scope and/or
|
||||
shared between threads. Though it's possible to create a lock
|
||||
object outside of block scope and to share it between threads to do so
|
||||
would not be a typical usage. Nor are there any cases when such usage
|
||||
would be required.</p>
|
||||
|
||||
<p>Lock objects must maintain some state information. In order to allow
|
||||
a program to determine if a try_lock or timed_lock was successful the
|
||||
lock object must retain state indicating the success or failure of the
|
||||
call made in its constructor. If a lock object were to have such state
|
||||
and remain thread-safe it would need to synchronize access to the state
|
||||
information which would result in roughly doubling the time of most
|
||||
operations. Worse, since checking the state can occur only by a call
|
||||
after construction we'd have a race condition if the lock object
|
||||
were shared between threads.</p>
|
||||
|
||||
<p>So, to avoid the overhead of synchronizing access to the state
|
||||
information and to avoid the race condition the Boost.Threads library
|
||||
simply does nothing to make lock objects thread-safe. Instead, sharing
|
||||
a lock object between threads results in undefined behavior. Since the
|
||||
only proper usage of lock objects is within block scope this isn't
|
||||
a problem, and so long as the lock object is properly used there's
|
||||
no danger of any multi-threading issues.</p>
|
||||
|
||||
<h2><a name="thread">Rationale for Non-copyable Thread Type</a></h2>
|
||||
|
||||
<p>Programmers who are used to C libraries for multi-threaded
|
||||
programming are likely to wonder why Boost.Threads uses a non-copyable
|
||||
design for <a href="thread.html">boost::thread</a>. After all, the C
|
||||
thread types are copyable, and you often have a need for copying them
|
||||
within user code. However, careful comparison of C designs to C++
|
||||
designs shows a flaw in this logic.</p>
|
||||
|
||||
<p>All C types are copyable. It is, in fact, not possible to make a
|
||||
non-copyable type in C. For this reason types that represent system
|
||||
resources in C are often designed to behave very similarly to a pointer
|
||||
to dynamic memory. There's an API for acquiring the resource and an
|
||||
API for releasing the resources. For memory we have pointers as the
|
||||
type and alloc/free for the acquisition and release APIs. For files we
|
||||
have FILE* as the type and fopen/fclose for the acquisition and release
|
||||
APIs. You can freely copy instances of the types but must manually
|
||||
manage the lifetime of the actual resource through the acquisition and
|
||||
release APIs.</p>
|
||||
|
||||
<p>C++ designs recognize that the acquisition and release APIs are
|
||||
error prone and try to eliminate possible errors by acquiring the
|
||||
resource in the constructor and releasing it in the destructor. The
|
||||
best example of such a design is the std::iostream set of classes which
|
||||
can represent the same resource as the FILE* type in C. A file is
|
||||
opened in the std::fstream's constructor and closed in its
|
||||
destructor. However, if an iostream were copyable it could lead to a
|
||||
file being closed twice, an obvious error, so the std::iostream types
|
||||
are noncopyable by design. This is the same design used by
|
||||
boost::thread, which is a simple and easy to understand design
|
||||
that's consistent with other C++ standard types.</p>
|
||||
|
||||
<p>During the design of boost::thread it was pointed out that it would
|
||||
be possible to allow it to be a copyable type if some form of
|
||||
"reference management" were used, such as ref-counting or
|
||||
ref-lists, and many argued for a boost::thread_ref design instead. The
|
||||
reasoning was that copying "thread" objects was a typical
|
||||
need in the C libraries, and so presumably would be in the C++
|
||||
libraries as well. It was also thought that implementations could
|
||||
provide more efficient reference management then wrappers (such as
|
||||
boost::shared_ptr) around a noncopyable thread concept. Analysis of
|
||||
whether or not these arguments would hold true don't appear to bear
|
||||
them out. To illustrate the analysis we'll first provide
|
||||
pseudo-code illustrating the six typical usage patterns of a thread
|
||||
object.</p>
|
||||
|
||||
<h3>1. Simple creation of a thread.</h3>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
create_thread(&bar);
|
||||
}
|
||||
</pre>
|
||||
<h3>2. Creation of a thread that's later joined.</h3>
|
||||
<pre>Void foo()
|
||||
|
||||
<h3>2. Creation of a thread that's later joined.</h3>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
thread = create_thread(&bar);
|
||||
join(thread);
|
||||
}
|
||||
</pre>
|
||||
<h3>3. Simple creation of several threads in a loop.</h3>
|
||||
<pre>Void foo()
|
||||
|
||||
<h3>3. Simple creation of several threads in a loop.</h3>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
for (int i=0; i<NUM_THREADS; ++i)
|
||||
create_thread(&bar);
|
||||
}
|
||||
</pre>
|
||||
<h3>4. Creation of several threads in a loop which are later joined.</h3>
|
||||
<pre>Void foo()
|
||||
|
||||
<h3>4. Creation of several threads in a loop which are later
|
||||
joined.</h3>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
for (int i=0; i<NUM_THREADS; ++i)
|
||||
threads[i] = create_thread(&bar);
|
||||
@@ -172,40 +217,56 @@
|
||||
threads[i].join();
|
||||
}
|
||||
</pre>
|
||||
<h3>5. Creation of a thread whose ownership is passed to another object/method.</h3>
|
||||
<pre>Void foo()
|
||||
|
||||
<h3>5. Creation of a thread whose ownership is passed to another
|
||||
object/method.</h3>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
thread = create_thread(&bar);
|
||||
manager.owns(thread);
|
||||
}
|
||||
</pre>
|
||||
<h3>6. Creation of a thread whose ownership is shared between multiple objects.</h3>
|
||||
<pre>Void foo()
|
||||
|
||||
<h3>6. Creation of a thread whose ownership is shared between multiple
|
||||
objects.</h3>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
thread = create_thread(&bar);
|
||||
manager1.add(thread);
|
||||
manager2.add(thread);
|
||||
}
|
||||
</pre>
|
||||
<p>Of these usage patterns there's only one that requires reference management
|
||||
(number 6). Hopefully it's fairly obvious that this usage pattern simply
|
||||
won't occur as often as the other usage patterns. So there really isn't
|
||||
a "typical need" for a thread concept, though there is some need.</p>
|
||||
<p>Since the need isn't typical we must use different criteria for deciding
|
||||
on either a thread_ref or thread design. Possible criteria include ease of use
|
||||
and performance. So let's analyze both of these carefully.</p>
|
||||
<p>With ease of use we can look at existing experience. The standard C++ objects
|
||||
that represent a system resource, such as std::iostream, are noncopyable, so
|
||||
we know that C++ programmers must at least be experienced with this design.
|
||||
Most C++ developers are also used to smart pointers such as boost::shared_ptr,
|
||||
so we know they can at least adapt to a thread_ref concept with little effort.
|
||||
So existing experience isn't going to lead us to a choice.</p>
|
||||
<p>The other thing we can look at is how difficult it is to use both types for
|
||||
the six usage patterns above. If we find it overly difficult to use a concept
|
||||
for any of the usage patterns there would be a good argument for choosing the
|
||||
other design. So we'll code all six usage patterns using both designs.</p>
|
||||
<h3>1.</h3>
|
||||
<pre>void foo()
|
||||
|
||||
<p>Of these usage patterns there's only one that requires reference
|
||||
management (number 6). Hopefully it's fairly obvious that this
|
||||
usage pattern simply won't occur as often as the other usage
|
||||
patterns. So there really isn't a "typical need" for a
|
||||
thread concept, though there is some need.</p>
|
||||
|
||||
<p>Since the need isn't typical we must use different criteria for
|
||||
deciding on either a thread_ref or thread design. Possible criteria
|
||||
include ease of use and performance. So let's analyze both of these
|
||||
carefully.</p>
|
||||
|
||||
<p>With ease of use we can look at existing experience. The standard
|
||||
C++ objects that represent a system resource, such as std::iostream,
|
||||
are noncopyable, so we know that C++ programmers must at least be
|
||||
experienced with this design. Most C++ developers are also used to
|
||||
smart pointers such as boost::shared_ptr, so we know they can at least
|
||||
adapt to a thread_ref concept with little effort. So existing
|
||||
experience isn't going to lead us to a choice.</p>
|
||||
|
||||
<p>The other thing we can look at is how difficult it is to use both
|
||||
types for the six usage patterns above. If we find it overly difficult
|
||||
to use a concept for any of the usage patterns there would be a good
|
||||
argument for choosing the other design. So we'll code all six usage
|
||||
patterns using both designs.</p>
|
||||
|
||||
<h3>1.</h3>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
thread thrd(&bar);
|
||||
}
|
||||
@@ -215,8 +276,10 @@ void foo()
|
||||
thread_ref thrd = create_thread(&bar);
|
||||
}
|
||||
</pre>
|
||||
<h3>2.</h3>
|
||||
<pre>void foo()
|
||||
|
||||
<h3>2.</h3>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
thread thrd(&bar);
|
||||
thrd.join();
|
||||
@@ -224,12 +287,14 @@ void foo()
|
||||
|
||||
void foo()
|
||||
{
|
||||
thread_ref thrd =
|
||||
thread_ref thrd =
|
||||
create_thread(&bar);thrd->join();
|
||||
}
|
||||
</pre>
|
||||
<h3>3.</h3>
|
||||
<pre>void foo()
|
||||
|
||||
<h3>3.</h3>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
for (int i=0; i<NUM_THREADS; ++i)
|
||||
thread thrd(&bar);
|
||||
@@ -241,8 +306,10 @@ void foo()
|
||||
thread_ref thrd = create_thread(&bar);
|
||||
}
|
||||
</pre>
|
||||
<h3>4.</h3>
|
||||
<pre>void foo()
|
||||
|
||||
<h3>4.</h3>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
std::auto_ptr<thread> threads[NUM_THREADS];
|
||||
for (int i=0; i<NUM_THREADS; ++i)
|
||||
@@ -257,11 +324,13 @@ void foo()
|
||||
for (int i=0; i<NUM_THREADS; ++i)
|
||||
threads[i] = create_thread(&bar);
|
||||
for (int i= 0; i<NUM_THREADS;
|
||||
++i)threads[i]->join();
|
||||
++i)threads[i]->join();
|
||||
}
|
||||
</pre>
|
||||
<h3>5.</h3>
|
||||
<pre>void foo()
|
||||
|
||||
<h3>5.</h3>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
thread thrd* = new thread(&bar);
|
||||
manager.owns(thread);
|
||||
@@ -273,8 +342,10 @@ void foo()
|
||||
manager.owns(thrd);
|
||||
}
|
||||
</pre>
|
||||
<h3>6.</h3>
|
||||
<pre>void foo()
|
||||
|
||||
<h3>6.</h3>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
boost::shared_ptr<thread> thrd(new thread(&bar));
|
||||
manager1.add(thrd);
|
||||
@@ -288,15 +359,18 @@ void foo()
|
||||
manager2.add(thrd);
|
||||
}
|
||||
</pre>
|
||||
<p>This shows the usage patterns being nearly identical in complexity for both
|
||||
designs. The only actual added complexity occurs because of the use of operator
|
||||
new in (4), (5) and (6) and the use of std::auto_ptr and boost::shared_ptr in
|
||||
(4) and (6) respectively. However, that's not really much added complexity,
|
||||
and C++ programmers are used to using these idioms any way. Some may dislike
|
||||
the presence of operator new in user code, but this can be eliminated by proper
|
||||
design of higher level concepts, such as the boost::thread_group class that
|
||||
simplifies example (4) down to:</p>
|
||||
<pre>void foo()
|
||||
|
||||
<p>This shows the usage patterns being nearly identical in complexity
|
||||
for both designs. The only actual added complexity occurs because of
|
||||
the use of operator new in (4), (5) and (6) and the use of
|
||||
std::auto_ptr and boost::shared_ptr in (4) and (6) respectively.
|
||||
However, that's not really much added complexity, and C++
|
||||
programmers are used to using these idioms any way. Some may dislike
|
||||
the presence of operator new in user code, but this can be eliminated
|
||||
by proper design of higher level concepts, such as the
|
||||
boost::thread_group class that simplifies example (4) down to:</p>
|
||||
<pre>
|
||||
void foo()
|
||||
{
|
||||
thread_group threads;
|
||||
for (int i=0; i<NUM_THREADS; ++i)
|
||||
@@ -304,80 +378,104 @@ void foo()
|
||||
threads.join_all();
|
||||
}
|
||||
</pre>
|
||||
<p>So ease of use is really a wash and not much help in picking a design.</p>
|
||||
<p>So what about performance? If you look at the above code examples we can analyze
|
||||
the theoretical impact to performance that both designs have. For (1) we can
|
||||
see that platforms that don't have a ref-counted native thread type (POSIX,
|
||||
for instance) will be impacted by a thread_ref design. Even if the native thread
|
||||
type is ref-counted there may be an impact if more state information has to
|
||||
be maintained for concepts foreign to the native API, such as clean up stacks
|
||||
for Win32 implementations. For (2) the performance impact will be identical
|
||||
to (1). The same for (3). For (4) things get a little more interesting and we
|
||||
find that theoretically at least the thread_ref may perform faster since the
|
||||
thread design requires dynamic memory allocation/deallocation. However, in practice
|
||||
there may be dynamic allocation for the thread_ref design as well, it will just
|
||||
be hidden from the user. As long as the implementation has to do dynamic allocations
|
||||
the thread_ref loses again because of the reference management. For (5) we see
|
||||
the same impact as we do for (4). For (6) we still have a possible impact to
|
||||
the thread design because of dynamic allocation but thread_ref no longer suffers
|
||||
because of its reference management, and in fact, theoretically at least, the
|
||||
thread_ref may do a better job of managing the references. All of this indicates
|
||||
that thread wins for (1), (2) and (3), with (4) and (5) the winner depends on
|
||||
the implementation and the platform but the thread design probably has a better
|
||||
chance, and with (6) it will again depend on the implementation and platform
|
||||
but this time we favor thread_ref slightly. Given all of this it's a narrow
|
||||
margin, but the thread design prevails.</p>
|
||||
<p>Given this analysis, and the fact that noncopyable objects for system resources
|
||||
are the normal designs that C++ programmers are used to dealing with, the <b>Boost.Threads</b>
|
||||
library has gone with a noncopyable design.</p>
|
||||
<h2><a name="events"></a>Rationale for not providing <i>Event Variables</i></h2>
|
||||
<p><i>Event variables</i> are simply far too error-prone. <a href=
|
||||
"condition.html">Condition variables</a> are a much safer alternative.</p>
|
||||
<p>[Note that Graphical User Interface <i>events</i> are a different concept,
|
||||
and are not what is being discussed here.]</p>
|
||||
<p>Event variables were one of the first synchronization primitives. They are
|
||||
still used today, for example, in the native Windows multithreading API.</p>
|
||||
<p>Yet both respected computer science researchers and experienced multithreading
|
||||
practitioners believe event variables are so inherently error-prone that they
|
||||
should never be used, and thus should not be part of a multithreading library.</p>
|
||||
<p>Per Brinch Hansen <a href="bibliography.html#Brinch-Hansen-73"> [Brinch Hansen
|
||||
73]</a> analyzed event variables in some detail, pointing out [emphasis his]
|
||||
that "<i>event operations force the programmer to be aware of the relative
|
||||
speeds of the sending and receiving processes</i>". His summary:</p>
|
||||
<blockquote>
|
||||
<p>We must therefore conclude that event variables of the previous type are
|
||||
impractical for system design. <i>The effect of an interaction between two
|
||||
processes must be independent of the speed at which it is carried out.</i></p>
|
||||
</blockquote>
|
||||
<p>Experienced programmers using the Windows platform today report that event
|
||||
variables are a continuing source of errors, even after previous bad experiences
|
||||
caused them to be very careful in their use of event variables. Overt problems
|
||||
can be avoided, for example, by teaming the event variable with a mutex, but
|
||||
that may just convert a <a href="definitions.html#definition-race-condition">race condition</a> into another problem,
|
||||
such as excessive resource use. One of the most distressing aspects of the experience
|
||||
reports is the claim that many defects are latent. That is, the programs appear
|
||||
to work correctly, but contain hidden timing dependencies which will cause them
|
||||
to fail when environmental factors or usage patterns change, altering relative
|
||||
thread timings.</p>
|
||||
<p>The decision to exclude event variables from <b>Boost.Threads</b> has been
|
||||
surprising to some Windows programmers. They have written programs which work
|
||||
using event variables, and wonder what the problem is. It seems similar to the
|
||||
"goto considered harmful" controversy of 30 years ago. It isn't
|
||||
that events, like gotos, can't be made to work, but rather that virtually
|
||||
all programs using alternatives will be easier to write, debug, read, maintain,
|
||||
and be less likely to contain latent defects.</p>
|
||||
<p>[Rationale provided by Beman Dawes]</p>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->09 January, 2003<!--webbot bot="Timestamp" endspan i-checksum="38582" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
<p>So ease of use is really a wash and not much help in picking a
|
||||
design.</p>
|
||||
|
||||
<p>So what about performance? If you look at the above code examples we
|
||||
can analyze the theoretical impact to performance that both designs
|
||||
have. For (1) we can see that platforms that don't have a
|
||||
ref-counted native thread type (POSIX, for instance) will be impacted
|
||||
by a thread_ref design. Even if the native thread type is ref-counted
|
||||
there may be an impact if more state information has to be maintained
|
||||
for concepts foreign to the native API, such as clean up stacks for
|
||||
Win32 implementations. For (2) the performance impact will be identical
|
||||
to (1). The same for (3). For (4) things get a little more interesting
|
||||
and we find that theoretically at least the thread_ref may perform
|
||||
faster since the thread design requires dynamic memory
|
||||
allocation/deallocation. However, in practice there may be dynamic
|
||||
allocation for the thread_ref design as well, it will just be hidden
|
||||
from the user. As long as the implementation has to do dynamic
|
||||
allocations the thread_ref loses again because of the reference
|
||||
management. For (5) we see the same impact as we do for (4). For (6) we
|
||||
still have a possible impact to the thread design because of dynamic
|
||||
allocation but thread_ref no longer suffers because of it's
|
||||
reference management, and in fact, theoretically at least, the
|
||||
thread_ref may do a better job of managing the references. All of this
|
||||
indicates that thread wins for (1), (2) and (3), with (4) and (5) the
|
||||
winner depends on the implementation and the platform but the thread
|
||||
design probably has a better chance, and with (6) it will again depend
|
||||
on the implementation and platform but this time we favor thread_ref
|
||||
slightly. Given all of this it's a narrow margin, but the thread
|
||||
design prevails.</p>
|
||||
|
||||
<p>Given this analysis, and the fact that noncopyable objects for
|
||||
system resources are the normal designs that C++ programmers are used
|
||||
to dealing with, the Boost.Threads library has gone with a noncopyable
|
||||
design.</p>
|
||||
|
||||
<h2>Rationale for not providing <i><a name="Events">Event</a>
|
||||
Variables</i></h2>
|
||||
|
||||
<p><i>Event variables</i> are simply far too error-prone. <a href=
|
||||
"condition.html">Condition variables</a> are a much safer
|
||||
alternative.</p>
|
||||
|
||||
<p>[Note that Graphical User Interface <i>events</i> are a different
|
||||
concept, and are not what is being discussed here.]</p>
|
||||
|
||||
<p>Event variables were one of the first synchronization primitives.
|
||||
They are still used today, for example, in the native Windows
|
||||
multithreading API.</p>
|
||||
|
||||
<p>Yet both respected computer science researchers and experienced
|
||||
multithreading practitioners believe event variables are so inherently
|
||||
error-prone that they should never be used, and thus should not be part
|
||||
of a multithreading library.</p>
|
||||
|
||||
<p>Per Brinch Hansen <a href="bibliography.html#Brinch-Hansen-73">
|
||||
[Brinch Hansen 73]</a> analyzed event variables in some detail,
|
||||
pointing out [emphasis his] that "<i>event operations force the
|
||||
programmer to be aware of the relative speeds of the sending and
|
||||
receiving processes</i>". His summary:</p>
|
||||
|
||||
<blockquote>
|
||||
<p>We must therefore conclude that event variables of the previous
|
||||
type are impractical for system design. <i>The effect of an
|
||||
interaction between two processes must be independent of the speed
|
||||
at which it is carried out.</i></p>
|
||||
</blockquote>
|
||||
|
||||
<p>Experienced programmers using the Windows platform today report that
|
||||
event variables are a continuing source of errors, even after previous
|
||||
bad experiences caused them to be very careful in their use of event
|
||||
variables. Overt problems can be avoided, for example, by teaming the
|
||||
event variable with a mutex, but that may just convert a <a href=
|
||||
"definitions.html#Race condition">race condition</a> into another
|
||||
problem, such as excessive resource use. One of the most distressing
|
||||
aspects of the experience reports is the claim that many defects are
|
||||
latent. That is, the programs appear to work correctly, but contain
|
||||
hidden timing dependencies which will cause them to fail when
|
||||
environmental factors or usage patterns change, altering relative
|
||||
thread timings.</p>
|
||||
|
||||
<p>The decision to exclude event variables from Boost.Threads has been
|
||||
surprising to some Windows programmers. They have written programs
|
||||
which work using event variables, and wonder what the problem is. It
|
||||
seems similar to the "goto considered harmful" controversy of
|
||||
30 years ago. It isn't that events, like gotos, can't be made
|
||||
to work, but rather that virtually all programs using alternatives will
|
||||
be easier to write, debug, read, maintain, and be less likely to
|
||||
contain latent defects.</p>
|
||||
|
||||
<p>[Rationale provided by Beman Dawes]</p>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
@@ -1,244 +1,368 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Header <boost/thread/recursive_mutex.hpp></title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Header <<a href="../../../boost/thread/recursive_mutex.hpp">boost/thread/recursive_mutex.hpp</a>></h2> </td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<h2>Contents</h2>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#classes">Classes</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-recursive_mutex">Class <code>recursive_mutex</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-recursive_mutex-synopsis">Class <code>recursive_mutex</code>
|
||||
synopsis</a></dt>
|
||||
<dt><a href="#class-recursive_mutex-ctors">Class <code>recursive_mutex</code>
|
||||
constructors and destructor</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#class-recursive_try_mutex">Class <code>recursive_try_mutex</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-recursive_try_mutex-synopsis">Class <code>recursive_try_mutex</code>
|
||||
synopsis</a></dt>
|
||||
<dt><a href="#class-recursive_try_mutex-ctors">Class <code>recursive_try_mutex</code>
|
||||
constructors and destructor</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#class-recursive_timed_mutex">Class <code>recursive_timed_mutex</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-recursive_timed_mutex-synopsis">Class <code>recursive_timed_mutex</code>
|
||||
synopsis</a></dt>
|
||||
<dt><a href="#class-recursive_timed_mutex-ctors">Class <code>recursive_timed_mutex</code>
|
||||
constructors and destructor</a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
<dt><a href="#examples">Example(s)</a></dt>
|
||||
</dl>
|
||||
<hr>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>Include the header <<a href="../../../boost/thread/recursive_mutex.hpp">boost/thread/recursive_mutex.hpp</a>>
|
||||
to define the <a href="#class-recursive_mutex">recursive_mutex</a>, <a href="#class-recursive_try_mutex">recursive_try_mutex</a>
|
||||
and <a href="#class-recursive_timed_mutex">recursive_timed_mutex</a> classes.</p>
|
||||
<p>The <a href="#class-recursive_mutex">recursive_mutex</a>, <a href="#class-recursive_try_mutex">recursive_try_mutex</a>
|
||||
and <a href="#class-recursive_timed_mutex">recursive_timed_mutex</a> classes
|
||||
are models of <a href="mutex_concept.html#Mutex-concept">Mutex</a>, <a href="mutex_concept.html#TryMutex-concept">TryMutex</a>,
|
||||
and <a href="mutex_concept.html#TimedMutex-concept">TimedMutex</a> respectively.
|
||||
These types should be used to synchronize access to shared resources when recursive
|
||||
locking by a single thread is likely to occur. A good example for this is when
|
||||
a class supplies "internal synchronization" to ensure <a href="definitions.html#Thread-safe">
|
||||
thread-safety</a> and a function of the class may have to call other functions
|
||||
of the class which also attempt to lock the mutex. For recursive locking mechanics,
|
||||
see <a href="mutex.html">mutexes</a>.</p>
|
||||
<p>Each class supplies one or more typedefs for lock types which model matching
|
||||
lock concepts. For the best possible performance you should use the mutex class
|
||||
that supports the minimum set of lock types that you need.</p>
|
||||
<table summary="lock types" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Mutex Class</b></td>
|
||||
<td><b>Lock name</b></td>
|
||||
<td><b>Lock Concept</b></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><a href="#recursive_mutex Synopsis"><code> recursive_mutex</code></a></td>
|
||||
<td valign="middle"><code>scoped_lock</code></td>
|
||||
<td valign="middle"><a href="lock_concept.html#ScopedLock"> ScopedLock</a></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code><a href="#recursive_try_mutex Synopsis"> recursive_try_mutex</a></code></td>
|
||||
<td valign="middle"><code>scoped_lock<br>
|
||||
scoped_try_lock</code></td>
|
||||
<td valign="middle"><a href="lock_concept.html#ScopedLock"> ScopedLock</a><br>
|
||||
<a href="lock_concept.html#ScopedTryLock"> ScopedTryLock</a></td>
|
||||
</tr>
|
||||
<tr>
|
||||
<td valign="top"><code><a href=
|
||||
"#recursive_timed_mutex Synopsis"> recursive_timed_mutex</a></code>
|
||||
</td>
|
||||
<td valign="middle"><code>scoped_lock<br>
|
||||
scoped_try_lock<br>
|
||||
scoped_timed_lock</code></td>
|
||||
<td valign="middle"><a href="lock_concept.html#ScopedLock"> ScopedLock</a><br>
|
||||
<a href="lock_concept.html#ScopedTryLock"> ScopedTryLock</a><br>
|
||||
<a href="lock_concept.html#ScopedTimedLock"> ScopedTimedLock</a></td>
|
||||
</tr>
|
||||
</table>
|
||||
<p>The <code>recursive_mutex</code>, <code>recursive_try_mutex</code> and <code>recursive_timed_mutex</code>
|
||||
employ a <code>Recursive</code> <a href="mutex_concept.html#LockingStrategies">locking
|
||||
strategy</a>, so attempts to recursively lock them succeed and an internal "lock
|
||||
count" is maintained. Attempts to unlock them by a thread that does not
|
||||
own a lock on them will result in <b>undefined behavior</b>.</p>
|
||||
<p>The <code>recursive_mutex</code>, <code>recursive_try_mutex</code> and <code>recursive_timed_mutex</code>
|
||||
leave the <a href=
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, recursive_mutex</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0" width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">recursive_mutex<br>
|
||||
recursive_try_mutex<br>
|
||||
recursive_timed_mutex</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#recursive_mutex Synopsis">Class recursive_mutex
|
||||
Synopsis</a><br>
|
||||
<a href="#recursive_mutex Members">Class recursive_mutex
|
||||
Members</a><br>
|
||||
<a href="#recursive_try_mutex Synopsis">Class recursive_try_mutex
|
||||
Synopsis</a><br>
|
||||
<a href="#recursive_try_mutex Members">Class recursive_try_mutex
|
||||
Members</a><br>
|
||||
<a href="#recursive_timed_mutex Synopsis">Class recursive_timed_mutex
|
||||
Synopsis</a><br>
|
||||
<a href="#recursive_timed_mutex Members">Class recursive_timed_mutex
|
||||
Members</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>The <code>recursive_mutex</code>, <code>recursive_try_mutex</code>
|
||||
and <code>recursive_timed_mutex</code> classes define full featured
|
||||
models of the <a href="mutex_concept.html#Mutex">Mutex</a>, <a href=
|
||||
"mutex_concept.html#TryMutex">TryMutex</a> and <a href=
|
||||
"mutex_concept.html#TimedMutex">TimedMutex</a> concepts with recursive
|
||||
locking semantics. These types should be used to synchronize access to
|
||||
shared resources when recursive locking by a single thread is likely to
|
||||
occur. A good example for this is when a class supplies "internal
|
||||
synchronization" to ensure <a href="definitions.html#Thread-safe">
|
||||
thread-safety</a> and a function of the class may have to call other
|
||||
functions of the class which also attempt to lock the mutex. For
|
||||
recursive locking mechanics, see <a href="mutex.html">mutexes</a>.</p>
|
||||
|
||||
<p>Each class supplies one or more typedefs for lock types which model
|
||||
matching lock concepts. For the best possible performance you should
|
||||
use the mutex class that supports the minimum set of lock types that
|
||||
you need.</p>
|
||||
|
||||
<table summary="lock types" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><b>Mutex Class</b></td>
|
||||
|
||||
<td><b>Lock name</b></td>
|
||||
|
||||
<td><b>Implementation defined Lock Type</b></td>
|
||||
|
||||
<td><b>Lock Concept</b></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><a href="#recursive_mutex Synopsis"><code>
|
||||
recursive_mutex</code></a></td>
|
||||
|
||||
<td valign="middle"><code>scoped_lock</code></td>
|
||||
|
||||
<td valign="middle"><a href="scoped_lock.html"><code>
|
||||
detail::thread::scoped_lock<recursive_mutex></code></a></td>
|
||||
|
||||
<td valign="middle"><a href="lock_concept.html#ScopedLock">
|
||||
ScopedLock</a></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code><a href="#recursive_try_mutex Synopsis">
|
||||
recursive_try_mutex</a></code></td>
|
||||
|
||||
<td valign="middle"><code>scoped_lock<br>
|
||||
scoped_try_lock</code></td>
|
||||
|
||||
<td valign="middle"><a href="scoped_lock.html"><code>
|
||||
detail::thread::scoped_lock<recursive_try_mutex><br>
|
||||
</code></a> <code><a href="scoped_try_lock.html">
|
||||
detail::thread::scoped_try_lock<recursive_try_mutex></a></code></td>
|
||||
|
||||
<td valign="middle"><a href="lock_concept.html#ScopedLock">
|
||||
ScopedLock</a><br>
|
||||
<a href="lock_concept.html#ScopedTryLock">
|
||||
ScopedTryLock</a></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td valign="top"><code><a href=
|
||||
"#recursive_timed_mutex Synopsis">
|
||||
recursive_timed_mutex</a></code> </td>
|
||||
|
||||
<td valign="middle"><code>scoped_lock<br>
|
||||
scoped_try_lock<br>
|
||||
scoped_timed_lock</code></td>
|
||||
|
||||
<td valign="middle"><a href="scoped_lock.html"><code>
|
||||
detail::thread::scoped_lock<recursive_timed_mutex></code></a><br>
|
||||
|
||||
<a href="scoped_try_lock.html"><code>
|
||||
detail::thread::scoped_try_lock<recursive_timed_mutex></code></a><br>
|
||||
|
||||
<a href="scoped_timed_lock.html"><code>
|
||||
detail::thread::scoped_timed_lock<recursive_timed_mutex></code></a></td>
|
||||
|
||||
<td valign="middle"><a href="lock_concept.html#ScopedLock">
|
||||
ScopedLock</a><br>
|
||||
<a href="lock_concept.html#ScopedTryLock">
|
||||
ScopedTryLock</a><br>
|
||||
<a href="lock_concept.html#ScopedTimedLock">
|
||||
ScopedTimedLock</a></td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<p>The <code>recursive_mutex</code>, <code>recursive_try_mutex</code>
|
||||
and <code>recursive_timed_mutex</code> employ a <code>Recursive</code>
|
||||
<a href="mutex_concept.html#LockingStrategies">locking strategy</a>, so
|
||||
attempts to recursively lock them succeed and an internal "lock
|
||||
count" is maintained. Attempts to unlock them by a thread that
|
||||
does not own a lock on them will result in a <a href="lock_error.html">
|
||||
lock_error</a> exception being thrown.</p>
|
||||
|
||||
<p>The <code>recursive_mutex</code>, <code>recursive_try_mutex</code>
|
||||
and <code>recursive_timed_mutex</code> leave the <a href=
|
||||
"mutex_concept.html#SchedulingPolicies">scheduling policy</a> as <code>
|
||||
Unspecified</code>. Programmers should assume that threads waiting for a lock
|
||||
on objects of these types acquire the lock in a random order, even though the
|
||||
specific behavior for a given platform may be different.</p>
|
||||
<h2><a name="classes"></a>Classes</h2>
|
||||
<h3><a name="class-recursive_mutex"></a>Class <code>recursive_mutex</code></h3>
|
||||
<p>The <code>recursive_mutex</code> class is a model of <a href="mutex_concept.html#Mutex-concept">Mutex</a>
|
||||
and <a href="overview.html#non-copyable">NonCopyable</a>, and provides no additional
|
||||
facilities beyond the requirements of these concepts.</p>
|
||||
<h4><a name="class-recursive_mutex-synopsis"></a>Class <code>recursive_mutex</code>
|
||||
synopsis</h4>
|
||||
Unspecified</code>. Programmers should assume that threads waiting for
|
||||
a lock on objects of these types acquire the lock in a random order,
|
||||
even though the specific behavior for a given platform may be
|
||||
different.</p>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/recursive_mutex.hpp"><boost/thread/recursive_mutex.hpp></a>
|
||||
</pre>
|
||||
|
||||
<h2>Class <a name="recursive_mutex Synopsis">recursive_mutex
|
||||
Synopsis</a></h2>
|
||||
<hr>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
class recursive_mutex : private boost::noncopyable // Exposition only.
|
||||
// Class recursive_mutex meets the NonCopyable requirement.
|
||||
class recursive_mutex : private <a href=
|
||||
"../../utility/utility.htm">boost::noncopyable</a> // Exposition only.
|
||||
// Class recursive_mutex meets the <a href=
|
||||
"overview.html#NonCopyable">NonCopyable</a> requirement.
|
||||
{
|
||||
public:
|
||||
typedef <i>[implementation defined; see <a href=
|
||||
"#Introduction">Introduction</a>]</i> scoped_lock;
|
||||
|
||||
recursive_mutex();
|
||||
~recursive_mutex();
|
||||
};
|
||||
}
|
||||
</pre>
|
||||
|
||||
<h2>Class <a name="recursive_mutex Members">recursive_mutex
|
||||
Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
recursive_mutex();
|
||||
</pre>
|
||||
|
||||
<p><b>Postconditions:</b> <code>*this</code> is in the unlocked
|
||||
state.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~recursive_mutex();
|
||||
</pre>
|
||||
|
||||
<p><b>Requires:</b> <code>*this</code> is in the unlocked state.</p>
|
||||
|
||||
<p><b>Effects:</b> Destroys <code>*this</code>.</p>
|
||||
|
||||
<p><b>Dangers:</b> Destruction of a locked mutex is a serious
|
||||
programming error resulting in undefined behavior such as a program
|
||||
crash..</p>
|
||||
<hr>
|
||||
|
||||
<h2>Class <a name="recursive_try_mutex Synopsis">recursive_try_mutex
|
||||
Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
class recursive_try_mutex : private boost::noncopyable // Exposition only.
|
||||
// Class recursive_try_mutex meets the <a href=
|
||||
"overview.html#NonCopyable">NonCopyable</a> requirement.
|
||||
{
|
||||
public:
|
||||
typedef [implementation defined; see Introduction] scoped_lock;
|
||||
|
||||
recursive_mutex();
|
||||
~recursive_mutex();
|
||||
typedef <i>[implementation defined; see <a href=
|
||||
"#Introduction">Introduction</a>]</i> scoped_lock;
|
||||
typedef <i>[implementation defined; see <a href=
|
||||
"#Introduction">Introduction</a>]</i> scoped_try_lock;
|
||||
|
||||
recursive_try_mutex();
|
||||
~recursive_try_mutex();
|
||||
};
|
||||
};
|
||||
}
|
||||
</pre>
|
||||
<h4><a name="class-recursive_mutex-ctors"></a>Class <code>recursive_mutex</code>
|
||||
constructors and destructor</h4>
|
||||
<pre>
|
||||
recursive_mutex();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Postconditions:</b> <code>*this</code> is in an unlocked state.</dt>
|
||||
</dl>
|
||||
<pre>
|
||||
~recursive_mutex();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> <code>*this</code> is in an unlocked sate.</dt>
|
||||
<dt><b>Danger:</b> Destruction of a locked mutex is a serious programming error
|
||||
resulting in undefined behavior such as a program crash.</dt>
|
||||
</dl>
|
||||
<h3><a name="class-recursive_try_mutex"></a>Class <code>recursive_try_mutex</code></h3>
|
||||
<p>The <code>recursive_try_mutex</code> class is a model of <a href="mutex_concept.html#TryMutex-concept">TryMutex</a>
|
||||
and <a href="overview.html#non-copyable">NonCopyable</a>, and provides no additional
|
||||
facilities beyond the requirements of these concepts.</p>
|
||||
<h4><a name="class-recursive_try_mutex-synopsis"></a>Class <code>recursive_try_mutex</code>
|
||||
synopsis</h4>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
class recursive_mutex : private boost::noncopyable // Exposition only.
|
||||
// Class recursive_mutex meets the NonCopyable requirement.
|
||||
{
|
||||
Public:
|
||||
typedef [implementation defined; see Introduction] scoped_lock;
|
||||
typedef [implementation defined; see Introduction] scoped_try_lock;
|
||||
|
||||
recursive_try_mutex();
|
||||
~recursive_try_mutex();
|
||||
};
|
||||
};
|
||||
</pre>
|
||||
<h4><a name="class-recursive_try_mutex-ctors"></a>Class <code>recursive_try_mutex</code>
|
||||
constructors and destructor</h4>
|
||||
<h2>Class <a name="recursive_try_mutex Members">recursive_try_mutex
|
||||
Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
recursive_try_mutex();
|
||||
recursive_try_mutex();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Postconditions:</b> <code>*this</code> is in an unlocked state.</dt>
|
||||
</dl>
|
||||
|
||||
<p><b>Postconditions:</b> <code>*this</code> is in the unlocked
|
||||
state.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~recursive_try_mutex();
|
||||
~recursive_try_mutex();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> <code>*this</code> is in an unlocked sate.</dt>
|
||||
<dt><b>Danger:</b> Destruction of a locked mutex is a serious programming error
|
||||
resulting in undefined behavior such as a program crash.</dt>
|
||||
</dl>
|
||||
<h3><a name="class-recursive_timed_mutex"></a>Class <code>recursive_timed_mutex</code></h3>
|
||||
<p>The <code>recursive_timed_mutex</code> class is a model of <a href="mutex_concept.html#TimedMutex-concept">TimedMutex</a>
|
||||
and <a href="overview.html#non-copyable">NonCopyable</a>, and provides no additional
|
||||
facilities beyond the requirements of these concepts.</p>
|
||||
<h4><a name="class-recursive_timed_mutex-synopsis"></a>Class <code>recursive_timed_mutex</code>
|
||||
synopsis</h4>
|
||||
|
||||
<p><b>Requires:</b> <code>*this</code> is in the unlocked state.</p>
|
||||
|
||||
<p><b>Effects:</b> Destroys <code>*this</code>.</p>
|
||||
|
||||
<p><b>Dangers:</b> Destruction of a locked mutex is a serious
|
||||
programming error resulting in undefined behavior such as a program
|
||||
crash..</p>
|
||||
<hr>
|
||||
|
||||
<h2>Class <a name="recursive_timed_mutex Synopsis">
|
||||
recursive_timed_mutex Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
class recursive_timed_mutex : private boost::noncopyable // Exposition only.
|
||||
// Class recursive_mutex meets the NonCopyable requirement.
|
||||
// Class recursive_timed_mutex meets the <a href=
|
||||
"overview.html#NonCopyable">NonCopyable</a> requirement.
|
||||
{
|
||||
Public:
|
||||
typedef [implementation defined; see Introduction] scoped_lock;
|
||||
typedef [implementation defined; see Introduction] scoped_try_lock;
|
||||
typedef [implementation defined; see Introduction] scoped_timed_lock;
|
||||
|
||||
recursive_timed_mutex();
|
||||
~recursive_timed_mutex();
|
||||
public:
|
||||
typedef <i>[implementation defined; see <a href=
|
||||
"#Introduction">Introduction</a>]</i> scoped_lock;
|
||||
typedef <i>[implementation defined; see <a href=
|
||||
"#Introduction">Introduction</a>]</i> scoped_try_lock;
|
||||
typedef <i>[implementation defined; see <a href=
|
||||
"#Introduction">Introduction</a>]</i> scoped_timed_lock;
|
||||
|
||||
recursive_timed_mutex();
|
||||
~recursive_timed_mutex();
|
||||
};
|
||||
}
|
||||
</pre>
|
||||
|
||||
<h2>Class <a name="recursive_timed_mutex Members">recursive_timed_mutex
|
||||
Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
recursive_timed_mutex();
|
||||
</pre>
|
||||
|
||||
<p><b>Postconditions:</b> <code>*this</code> is in the unlocked
|
||||
state.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~recursive_timed_mutex();
|
||||
</pre>
|
||||
|
||||
<p><b>Requires:</b> <code>*this</code> is in the unlocked state.</p>
|
||||
|
||||
<p><b>Effects:</b> Destroys <code>*this</code>.</p>
|
||||
|
||||
<p><b>Dangers:</b> Destruction of a locked mutex is a serious
|
||||
programming error resulting in undefined behavior such as a program
|
||||
crash..</p>
|
||||
<hr>
|
||||
|
||||
<h2><a name="Example">Example</a> Usage</h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/recursive_mutex.hpp"><boost/thread/recursive_mutex.hpp></a>
|
||||
#include <a href=
|
||||
"../../../boost/thread/thread.hpp"><boost/thread/thread.hpp></a>
|
||||
#include <iostream>
|
||||
|
||||
class counter
|
||||
{
|
||||
public:
|
||||
counter() : count(0) { }
|
||||
|
||||
int add(int val) {
|
||||
boost::recursive_mutex::scoped_lock scoped_lock(mutex);
|
||||
count += val;
|
||||
return count;
|
||||
}
|
||||
int increment() {
|
||||
boost::recursive_mutex::scoped_lock scoped_lock(mutex);
|
||||
return add(1);
|
||||
}
|
||||
|
||||
private:
|
||||
boost::recursive_mutex mutex;
|
||||
int count;
|
||||
};
|
||||
|
||||
counter c;
|
||||
|
||||
void change_count(void*)
|
||||
{
|
||||
std::cout << "count == " << c.increment() << std::endl;
|
||||
}
|
||||
|
||||
int main(int, char*[])
|
||||
{
|
||||
const int num_threads=4;
|
||||
|
||||
boost::thread_group threads;
|
||||
for (int i=0; i < num_threads; ++i)
|
||||
threads.create_thread(&change_count, 0);
|
||||
|
||||
threads.join_all();
|
||||
|
||||
return 0;
|
||||
}
|
||||
</pre>
|
||||
<h4><a name="class-recursive_timed_mutex-ctors"></a>Class <code>recursive_timed_mutex</code>
|
||||
constructors and destructor</h4>
|
||||
<pre>
|
||||
recursive_timed_mutex();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Postconditions:</b> <code>*this</code> is in an unlocked state.</dt>
|
||||
</dl>
|
||||
<pre>
|
||||
~recursive_timed_mutex();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> <code>*this</code> is in an unlocked sate.</dt>
|
||||
<dt><b>Danger:</b> Destruction of a locked mutex is a serious programming error
|
||||
resulting in undefined behavior such as a program crash.</dt>
|
||||
</dl>
|
||||
<h2><a name="examples"></a>Example(s)</h2>
|
||||
<p><a href="../example/recursive_mutex.cpp">libs/thread/example/recursive_mutex.cpp</a></p>
|
||||
<p>The output is:</p>
|
||||
|
||||
<p>The output is:</p>
|
||||
<pre>
|
||||
count == 1
|
||||
count == 2
|
||||
count == 3
|
||||
count == 4
|
||||
</pre>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
134
doc/removed_atomic_t.html
Normal file
134
doc/removed_atomic_t.html
Normal file
@@ -0,0 +1,134 @@
|
||||
<html>
|
||||
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
<title>Boost.Threads, atomic_t</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width="277" height="86"></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">atomic_t</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<hr>
|
||||
|
||||
<h2>Header</h2>
|
||||
|
||||
<p>The <tt>atomic_t</tt> class defines an "atomic integer" type. This class should be used
|
||||
to perform thread safe operations on an integral type with out the overhead of locks. Only
|
||||
a limited set of integer operations are available with an <tt>atomic_t</tt> instance.</p>
|
||||
|
||||
<pre>
|
||||
#include <boost/thread/atomic.hpp>
|
||||
</pre>
|
||||
|
||||
<h2>Public Interface</h2>
|
||||
|
||||
<pre>
|
||||
class atomic_t
|
||||
{
|
||||
public:
|
||||
typedef <b>implementation defined</b> value_type;
|
||||
|
||||
explicit atomic_t(value_type val=0);
|
||||
};
|
||||
|
||||
atomic_t::value_type read(const atomic_t& x);
|
||||
atomic_t::value_type increment(atomic_t& x);
|
||||
atomic_t::value_type decrement(atomic_t& x);
|
||||
atomic_t::value_type swap(atomic_t& x, atomic_t::value_type y);
|
||||
atomic_t::value_type compare_swap(atomic_t& x, atomic_t::value_type y, atomic_t::value_type z);
|
||||
</pre>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
|
||||
<pre>
|
||||
atomic_t(atomic_t::value_type val=0);
|
||||
</pre>
|
||||
|
||||
<p>Constructs an <tt>atomic_t</tt> and sets its value to <tt>val</tt>.</p>
|
||||
|
||||
<h3>read</h3>
|
||||
|
||||
<pre>
|
||||
atomic_t::value_type read(const atomic_t& x);
|
||||
</pre>
|
||||
|
||||
<p>Gets the current value of <tt>x</tt>.</p>
|
||||
|
||||
<h3>increment</h3>
|
||||
|
||||
<pre>
|
||||
atomic_t::value_type increment(atomic_t& x);
|
||||
</pre>
|
||||
|
||||
<p>Increments <tt>x</tt> and returns a value <tt>< 0</tt> if the result is less than 0,
|
||||
<tt>> 0</tt> if the result is greater than 0 and <tt>== 0</tt> if the result is equal to
|
||||
0.</p>
|
||||
|
||||
<h3>decrement</h3>
|
||||
|
||||
<pre>
|
||||
atomic_t::value_type decrement(atomic_t& x);
|
||||
</pre>
|
||||
|
||||
<p>Decrements <tt>x</tt> and returns a value <tt>< 0</tt> if the result is less than 0,
|
||||
<tt>> 0</tt> if the result is greater than 0 and <tt>== 0</tt> if the result is equal to
|
||||
0.</p>
|
||||
|
||||
<h3>swap</h3>
|
||||
|
||||
<pre>
|
||||
atomic_t::value_type swap(atomic_t& x, atomic_t::value_type y);
|
||||
</pre>
|
||||
|
||||
<p>Assigns the value of <tt>y</tt> to <tt>x</tt> and returns the value of <tt>x</tt> prior
|
||||
to the swap.</p>
|
||||
|
||||
<h3>compare_swap</h3>
|
||||
|
||||
<pre>
|
||||
atomic_t::value_type compare_swap(atomic_t& x, atomic_t::value_type y, atomic_t::value_type z);
|
||||
</pre>
|
||||
|
||||
<p>Compares the value of <tt>z</tt> to the value of <tt>x</tt> and if equal sets the value of
|
||||
<tt>x</tt> to the value of <tt>y</tt> and returns the value of <tt>x</tt> prior to the swap.</p>
|
||||
|
||||
<h2>Example Usage</h2>
|
||||
|
||||
<pre>
|
||||
#include <boost/thread/atomic.hpp>
|
||||
#include <boost/test/test_tools.hpp>
|
||||
|
||||
int test_main(int, char*[])
|
||||
{
|
||||
boost::atomic_t a;
|
||||
BOOST_TEST_VERIFY(boost::read(a) == 0);
|
||||
BOOST_TEST_VERIFY(boost::increment(a) > 0);
|
||||
BOOST_TEST_VERIFY(boost::decrement(a) == 0);
|
||||
BOOST_TEST_VERIFY(boost::swap(a, 1) == 0);
|
||||
BOOST_TEST_VERIFY(boost::swap(a, 2, 0) == 1);
|
||||
BOOST_TEST_VERIFY(boost::read(a) == 1);
|
||||
}
|
||||
</pre>
|
||||
|
||||
<hr>
|
||||
|
||||
<p>Revised <!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">William E. Kempf</a>
|
||||
2001 all rights reserved.</i></p>
|
||||
|
||||
</body>
|
||||
</html>
|
||||
227
doc/scoped_lock.html
Normal file
227
doc/scoped_lock.html
Normal file
@@ -0,0 +1,227 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, scoped_lock</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">scoped_lock</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#Synopsis">Synopsis</a><br>
|
||||
<a href="#Members">Members</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>This class template defines a generic lock type which meets the <a
|
||||
href="lock_concept.html#ScopedLock">ScopedLock</a> requirements. The <a
|
||||
href="mutex.html">mutex</a>, <a href="mutex.html">try_mutex</a>, <a
|
||||
href="mutex.html">timed_mutex</a>, <a href="recursive_mutex.html">
|
||||
recursive_mutex</a>, <a href="recursive_mutex.html">
|
||||
recursive_try_mutex</a> and <a href="recursive_mutex.html">
|
||||
recursive_timed_mutex</a> classes all use this template to define their
|
||||
<code>scoped_lock</code> types.</p>
|
||||
|
||||
<p>Like all the <b>Boost.Threads</b> <a href="lock_concept.html">lock
|
||||
models</a>, <code>scoped_lock</code> objects are meant to be
|
||||
short-lived. Objects of the class are not <a href=
|
||||
"definitions.html#thread-safe">thread-safe</a>, and so should not be
|
||||
shared between threads.</p>
|
||||
|
||||
<p>Class <code>scoped_lock</code> follows the "resource
|
||||
acquisition is initialization" idiom <a href=
|
||||
"bibliography.html#Stroustrup-00">[Stroustrup 00 14.4.1]</a> and is a
|
||||
realization of the "Scoped Locking Pattern" <a href=
|
||||
"bibliography.html#Schmidt-00">[Schmidt-00]</a>. Thus the usage is to
|
||||
let the constructor do the locking, and then let the destructor do the
|
||||
unlocking automatically at the end of the enclosing scope. The lock()
|
||||
and unlock() members are usually not explicitly called, but are
|
||||
provided to allow for complex overlapping locks of multiple
|
||||
mutexes.</p>
|
||||
|
||||
<p>The type used to instantiate the class must meet the <a href=
|
||||
"mutex_concept.html#Mutex">Mutex</a> requirements.</p>
|
||||
|
||||
<p>Although this class is an implementation detail, it is publicly
|
||||
documented here because of its importance.</p>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/detail/lock.hpp"><boost/thread/detail/lock.hpp></a>
|
||||
<i>This header is usually not included directly by programmers
|
||||
because it is supplied by <a href=
|
||||
"../../../boost/thread/mutex.hpp"><boost/thread/mutex.hpp></a> or
|
||||
<a href=
|
||||
"../../../boost/thread/recursive_mutex.hpp"><boost/thread/recursive_mutex.hpp></a></i>
|
||||
</pre>
|
||||
|
||||
<h2><a name="Synopsis">Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost { namespace detail { namespace thread {
|
||||
template <typename Mutex>
|
||||
class scoped_lock : private <a href=
|
||||
"../../utility/utility.htm#Class noncopyable">boost::noncopyable</a> // Exposition only.
|
||||
// Class scoped_lock meets the <a href=
|
||||
"overview.html#NonCopyable">NonCopyable</a> requirement.
|
||||
{
|
||||
public:
|
||||
typedef Mutex mutex_type;
|
||||
|
||||
explicit scoped_lock(Mutex& mx, bool initially_locked=true);
|
||||
~scoped_lock();
|
||||
|
||||
void lock();
|
||||
void unlock();
|
||||
|
||||
operator const void*() const;
|
||||
bool locked() const;
|
||||
};
|
||||
} // namespace thread
|
||||
} // namespace detail
|
||||
} // namespace boost
|
||||
</pre>
|
||||
|
||||
<h2><a name="Members">Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
explicit scoped_lock(Mutex& mx, bool initially_locked=true);
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Associates mutex <code>mx</code> with <code>
|
||||
*this</code>. If <code>initially_locked</code> is <code>true,</code>
|
||||
calls <code>lock()</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~scoped_lock();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> If <code>locked()</code>, calls <code>
|
||||
unlock()</code>. Destroys <code>*this</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>lock</h3>
|
||||
<pre>
|
||||
void lock();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> If the associated mutex is already locked by another
|
||||
lock in the current thread, the effects depend on the locking strategy
|
||||
of the associated mutex, as shown in the following table:</p>
|
||||
|
||||
<table summary="lock effects" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><i><a href="mutex_concept.html#LockingStrategies">Locking
|
||||
Strategy</a><br>
|
||||
of associated mutex</i></td>
|
||||
|
||||
<td><i>Effect if associated mutex is already locked by the
|
||||
current thread</i></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Recursive</td>
|
||||
|
||||
<td>As if an additional lock were added to the mutex.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Checked</td>
|
||||
|
||||
<td>Throws <a href="lock_error.html">lock_error</a>.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Unchecked</td>
|
||||
|
||||
<td>Undefined behavior [<a href="bibliography.html#ISO">ISO</a>
|
||||
1.3.12] (but typically, <a href="definitions.html#Deadlock">
|
||||
deadlock</a>.)</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<p>If the associated mutex is already locked by some other thread,
|
||||
places the current thread in the <a href="definitions.html#State">
|
||||
Blocked</a> state until the associated mutex is unlocked, after which
|
||||
the current thread is placed in the <a href="definitions.html#State">
|
||||
Ready</a> state, eventually to be returned to the <a href=
|
||||
"definitions.html#State">Running</a> state.</p>
|
||||
|
||||
<p><b>Postcondition:</b> locked()</p>
|
||||
|
||||
<p><b>Throws:</b> <a href="lock_error.html">lock_error</a> if <code>
|
||||
locked()</code> or as indicated in <b>Effects</b>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>unlock</h3>
|
||||
<pre>
|
||||
void unlock();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Unlocks the associated mutex.</p>
|
||||
|
||||
<p><b>Throws:</b> <a href="lock_error.html">lock_error</a> if <code>
|
||||
!locked()</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>const void* Conversion</h3>
|
||||
<pre>
|
||||
operator const void*() const;
|
||||
</pre>
|
||||
|
||||
<p><b>Returns:</b> If the associated mutex is currently locked, a value
|
||||
convertible to <code>true</code>, else a value convertible to <code>
|
||||
false</code>.</p>
|
||||
|
||||
<p><b>Rationale:</b> A <code>const void*</code> conversion is
|
||||
considered safer than a conversion to <code>bool</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>locked</h3>
|
||||
<pre>
|
||||
bool locked() const;
|
||||
</pre>
|
||||
|
||||
<p><b>Returns:</b> <code>this->operator const void*() !=
|
||||
0</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h2><a name="Example">Example</a> Usage</h2>
|
||||
|
||||
<p>See the example given in the documentation for the <a href=
|
||||
"mutex.html">mutex</a> class.</p>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
267
doc/scoped_timed_lock.html
Normal file
267
doc/scoped_timed_lock.html
Normal file
@@ -0,0 +1,267 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, scoped_timed_lock</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">scoped_timed_lock</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#Synopsis">Synopsis</a><br>
|
||||
<a href="#Members">Members</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>This class template defines a generic lock type which meets the <a
|
||||
href="lock_concept.html#ScopedTimedLock">ScopedTimedLock</a>
|
||||
requirements. The <a href="mutex.html">timed_mutex</a> and <a href=
|
||||
"recursive_mutex.html">recursive_timed_mutex</a> classes use this
|
||||
template to define their <code>scoped_timed_lock</code> types.</p>
|
||||
|
||||
<p>Like all the <b>Boost.Threads</b> <a href="lock_concept.html">lock
|
||||
models</a>, <code>scoped_timed_lock</code> objects are meant to be
|
||||
short-lived. Objects of the class are not <a href=
|
||||
"definitions.html#thread-safe">thread-safe</a>, and so should not be
|
||||
shared between threads.</p>
|
||||
|
||||
<p>Class <code>scoped_timed_lock</code> follows the "resource
|
||||
acquisition is initialization" idiom <a href=
|
||||
"bibliography.html#Stroustrup-00">[Stroustrup 00 14.4.1]</a> and is a
|
||||
realization of the "Scoped Locking Pattern" <a href=
|
||||
"bibliography.html#Schmidt-00">[Schmidt-00]</a>. Thus the usage is to
|
||||
let the constructor do the locking, and then let the destructor do the
|
||||
unlocking automatically at the end of the enclosing scope. The lock()
|
||||
and unlock() members are usually not explicitly called, but are
|
||||
provided to allow for complex overlapping locks of multiple
|
||||
mutexes.</p>
|
||||
|
||||
<p>The type used to instantiate the class must meet the <a href=
|
||||
"mutex_concept.html#TimedMutex">TimedMutex</a> requirements.</p>
|
||||
|
||||
<p>Although this class is an implementation detail, it is publicly
|
||||
documented here because of its importance.</p>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/detail/lock.hpp"><boost/thread/detail/lock.hpp></a>
|
||||
<i>This header is usually not included directly by programmers
|
||||
because it is supplied by <a href=
|
||||
"../../../boost/thread/mutex.hpp"><boost/thread/mutex.hpp></a> or
|
||||
<a href=
|
||||
"../../../boost/thread/recursive_mutex.hpp"><boost/thread/recursive_mutex.hpp></a></i>
|
||||
</pre>
|
||||
|
||||
<h2><a name="Synopsis">Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost { namespace detail { namespace thread {
|
||||
template <typename TimedMutex>
|
||||
class scoped_timed_lock : private <a href=
|
||||
"../../utility/utility.htm#Class noncopyable">boost::noncopyable</a> // Exposition only.
|
||||
// Class scoped_timed_lock meets the <a href=
|
||||
"overview.html#NonCopyable">NonCopyable</a> requirement.
|
||||
{
|
||||
public:
|
||||
typedef TimedMutex mutex_type;
|
||||
|
||||
scoped_timed_lock(TimedMutex& mx, const boost::xtime& xt);
|
||||
scoped_timed_lock(TimedMutex& mx, bool initially_locked);
|
||||
~scoped_timed_lock();
|
||||
|
||||
void lock();
|
||||
bool timed_lock(const xtime& xt);
|
||||
void unlock();
|
||||
|
||||
operator const void*() const;
|
||||
};
|
||||
} // namespace thread
|
||||
} // namesapce detail
|
||||
} // namespace boost
|
||||
</pre>
|
||||
|
||||
<h2><a name="Members">Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
scoped_timed_lock(TimedMutex& mx, const <a href=
|
||||
"xtime.html">xtime</a>& xt);
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Associates mutex <code>mx</code> with <code>
|
||||
*this</code>. Calls <code>timed_lock</code>( <code>xt</code>)</p>
|
||||
<hr>
|
||||
<pre>
|
||||
scoped_timed_lock(TimedMutex& mx, bool initially_locked);
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Associates mutex <code>mx</code> with <code>
|
||||
*this</code>. If <code>initially_locked</code> is <code>true</code>,
|
||||
calls <code>lock()</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~scoped_timed_lock();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> If <code>locked()</code>, calls <code>
|
||||
unlock()</code>. Destroys <code>*this</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>lock</h3>
|
||||
<pre>
|
||||
void lock();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> If the associated mutex is already locked by another
|
||||
lock in the current thread, the effects depend on the locking strategy
|
||||
of the associated mutex, as shown in the following table:</p>
|
||||
|
||||
<table summary="lock effects" border="1" cellpadding="5">
|
||||
<tr>
|
||||
<td><i><a href="mutex_concept.html#LockingStrategies">Locking
|
||||
Strategy</a><br>
|
||||
of associated mutex</i></td>
|
||||
|
||||
<td><i>Effect if associated mutex is already locked by the
|
||||
current thread</i></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Recursive</td>
|
||||
|
||||
<td>As if an additional lock were added to the mutex.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Checked</td>
|
||||
|
||||
<td>Throws <a href="lock_error.html">lock_error</a>.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td>Unchecked</td>
|
||||
|
||||
<td>Undefined behavior [<a href="bibliography.html#ISO">ISO</a>
|
||||
1.3.12] (but typically, <a href="definitions.html#Deadlock">
|
||||
deadlock</a>.)</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<p>If the associated mutex is already locked by some other thread,
|
||||
places the current thread in the <a href="definitions.html#State">
|
||||
Blocked</a> state until the associated mutex is unlocked, after which
|
||||
the current thread is placed in the <a href="definitions.html#State">
|
||||
Ready</a> state, eventually to be returned to the <a href=
|
||||
"definitions.html#State">Running</a> state. Places the associated mutex
|
||||
in the locked state.</p>
|
||||
|
||||
<p><b>Throws:</b> <a href="lock_error.html">lock_error</a> if <code>
|
||||
locked()</code> or as indicated in <b>Effects</b>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>timed_lock</h3>
|
||||
<pre>
|
||||
bool timed_lock(const <a href="xtime.html">xtime</a>& xt);
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Same as <code>lock()</code>, except that if xt is
|
||||
reached, places the current thread in the <a href=
|
||||
"definitions.html#State">Ready</a> state without further ado.</p>
|
||||
|
||||
<p><b>Returns:</b> <code>locked()</code>.</p>
|
||||
|
||||
<p><b>Throws:</b> <a href="lock_error.html">lock_error</a> if <code>
|
||||
locked()</code> or as indicated in <b>Effects</b>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>unlock</h3>
|
||||
<pre>
|
||||
void unlock();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Unlocks the associated mutex.</p>
|
||||
|
||||
<p><b>Throws:</b> <a href="lock_error.html">lock_error</a> if <code>
|
||||
!locked()</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>const void* Conversion</h3>
|
||||
<pre>
|
||||
operator const void*() const;
|
||||
</pre>
|
||||
|
||||
<p><b>Returns:</b> If the associated mutex is currently locked, a value
|
||||
convertible to <code>true</code>, else a value convertible to <code>
|
||||
false</code>.</p>
|
||||
|
||||
<p><b>Rationale:</b> A <code>const void*</code> conversion is
|
||||
considered safer than a conversion to <code>bool</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>locked</h3>
|
||||
<pre>
|
||||
bool locked() const;
|
||||
</pre>
|
||||
|
||||
<p><b>Returns:</b> <code>this->operator const void*() !=
|
||||
0</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h2><a name="Example">Example</a> Usage</h2>
|
||||
<pre>
|
||||
#include <boost/thread/mutex.hpp>
|
||||
#include <iostream>
|
||||
|
||||
int main(int, char*[])
|
||||
{
|
||||
boost::timed_mutex mutex;
|
||||
boost::xtime xt;
|
||||
boost::get_xtime(&xt, boost::TIME_UTC);
|
||||
xt.sec += 1;
|
||||
boost::mutex::scoped_timed_lock scope_timed_lock(mutex, xt);
|
||||
if (scope_timed_lock.locked())
|
||||
std::cout << "locked" << std::endl;
|
||||
else
|
||||
std::cout << "unlocked" << std::endl;
|
||||
return 0;
|
||||
}
|
||||
</pre>
|
||||
|
||||
<p>The output is:</p>
|
||||
<pre>
|
||||
locked
|
||||
</pre>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%B %d, %Y" startspan -->November 05, 2001<!--webbot bot="Timestamp" endspan i-checksum="39585" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
305
doc/scoped_try_lock.html
Normal file
305
doc/scoped_try_lock.html
Normal file
@@ -0,0 +1,305 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, scoped_try_lock</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">scoped_try_lock</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#Synopsis">Synopsis</a><br>
|
||||
<a href="#Members">Members</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>This class template defines a generic lock type which meets the <a
|
||||
href="lock_concept.html#ScopedTryLock">ScopedTryLock</a> requirements.
|
||||
The <a href="mutex.html">try_mutex</a>, <a href="mutex.html">
|
||||
timed_mutex</a>, <a href="recursive_mutex.html">recursive_try_mutex</a>
|
||||
and <a href="recursive_mutex.html">recursive_timed_mutex</a> classes
|
||||
use this template to define their <code>scoped_try_lock</code>
|
||||
types.</p>
|
||||
|
||||
<p>Like all the <b>Boost.Threads</b> <a href="lock_concept.html">lock
|
||||
models</a>, <code>scoped_try_lock</code> objects are meant to be
|
||||
short-lived. Objects of the class are not <a href=
|
||||
"definitions.html#thread-safe">thread-safe</a>, and so should not be
|
||||
shared between threads.</p>
|
||||
|
||||
<p>Class <code>scoped_try_lock</code> follows the "resource
|
||||
acquisition is initialization" idiom <a href=
|
||||
"bibliography.html#Stroustrup-00">[Stroustrup 00 14.4.1]</a> and is a
|
||||
realization of the "Scoped Locking Pattern" <a href=
|
||||
"bibliography.html#Schmidt-00">[Schmidt-00]</a>. Thus the usage is to
|
||||
let the constructor do the locking, and then let the destructor do the
|
||||
unlocking automatically at the end of the enclosing scope. The lock()
|
||||
and unlock() members are usually not explicitly called, but are
|
||||
provided to allow for complex overlapping locks of multiple
|
||||
mutexes.</p>
|
||||
|
||||
<p>Although this class is an implementation detail, it is publicly
|
||||
documented here because of its importance.</p>
|
||||
|
||||
<p>The type used to instantiate the class must meet the <a href=
|
||||
"mutex_concept.html#TryMutex">TryMutex</a> requirements.</p>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/detail/lock.hpp"><boost/thread/detail/lock.hpp></a>
|
||||
<i>This header is usually not included directly by programmers
|
||||
because it is supplied by <a href=
|
||||
"../../../boost/thread/mutex.hpp"><boost/thread/mutex.hpp></a> or
|
||||
<a href=
|
||||
"../../../boost/thread/recursive_mutex.hpp"><boost/thread/recursive_mutex.hpp></a></i>
|
||||
</pre>
|
||||
|
||||
<h2><a name="Synopsis">Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost { namespace detail { namespace thread {
|
||||
template <typename TryMutex>
|
||||
class scoped_try_lock : private <a href=
|
||||
"../../utility/utility.htm#Class noncopyable">boost::noncopyable</a> // Exposition only.
|
||||
// Class scoped_try_lock meets the <a href=
|
||||
"overview.html#NonCopyable">NonCopyable</a> requirement.
|
||||
{
|
||||
public:
|
||||
typedef TryMutex mutex_type;
|
||||
|
||||
explicit scoped_try_lock(TryMutex& mx);
|
||||
scoped_try_lock(TryMutex& mx, bool initially_locked);
|
||||
~scoped_try_lock();
|
||||
|
||||
void lock();
|
||||
bool try_lock();
|
||||
void unlock();
|
||||
|
||||
operator const void*() const;
|
||||
};
|
||||
} // namespace thread
|
||||
} // namespace detail
|
||||
} // namespace boost
|
||||
</pre>
|
||||
|
||||
<h2><a name="Members">Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructors</h3>
|
||||
<pre>
|
||||
explicit scoped_try_lock(TryMutex& mx);
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Associates mutex <code>mx</code> with <code>
|
||||
*this</code>. Calls <code>try_lock()</code>.</p>
|
||||
<hr>
|
||||
<pre>
|
||||
scoped_try_lock(TryMutex& mx, bool initially_locked);
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Associates mutex <code>mx</code> with <code>
|
||||
*this</code>. If <code>initially_locked</code> is <code>true,</code>
|
||||
calls <code>lock()</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~scoped_try_lock();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> If <code>locked()</code>, calls <code>
|
||||
unlock()</code>. Destroys <code>*this</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>lock</h3>
|
||||
<pre>
|
||||
void lock();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> If the associated mutex is already locked by another
|
||||
lock in the current thread, the effects depend on the locking strategy
|
||||
of the associated mutex, as shown in the following table:</p>
|
||||
|
||||
<table summary="lock effects" border="1" cellpadding="5" height="147">
|
||||
<tr>
|
||||
<td height="34"><i><a href=
|
||||
"mutex_concept.html#LockingStrategies">Locking Strategy</a><br>
|
||||
of associated mutex</i></td>
|
||||
|
||||
<td height="34"><i>Effect if associated mutex is already locked
|
||||
by the current thread</i></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td height="19">Recursive</td>
|
||||
|
||||
<td height="19">As if an additional lock were added to the
|
||||
mutex.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td height="19">Checked</td>
|
||||
|
||||
<td height="19">Throws <a href="lock_error.html">
|
||||
lock_error</a>.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td height="19">Unchecked</td>
|
||||
|
||||
<td height="19">Undefined behavior [<a href=
|
||||
"bibliography.html#ISO">ISO</a> 1.3.12] (but typically, <a
|
||||
href="definitions.html#Deadlock">deadlock</a>.)</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<p>If the associated mutex is already locked by some other thread,
|
||||
places the current thread in the <a href="definitions.html#State">
|
||||
Blocked</a> state until the associated mutex is unlocked, after which
|
||||
the current thread is placed in the <a href="definitions.html#State">
|
||||
Ready</a> state, eventually to be returned to the <a href=
|
||||
"definitions.html#State">Running</a> state. Places the associated mutex
|
||||
in the locked state.</p>
|
||||
|
||||
<p><b>Throws:</b> <a href="lock_error.html">lock_error</a> if <code>
|
||||
locked()</code> or as indicated in <b>Effects</b>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>try_lock</h3>
|
||||
<pre>
|
||||
bool try_lock();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> If the associated mutex is already locked by another
|
||||
lock in the current thread, the effects depend on the locking strategy
|
||||
of the associated mutex, as shown in the following table:</p>
|
||||
|
||||
<table summary="try_lock effects" border="1" cellpadding="5" height=
|
||||
"147">
|
||||
<tr>
|
||||
<td height="34"><i><a href=
|
||||
"mutex_concept.html#LockingStrategies">Locking Strategy</a><br>
|
||||
of associated mutex</i></td>
|
||||
|
||||
<td height="34"><i>Effect if associated mutex is already locked
|
||||
by the current thread</i></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td height="19">Recursive</td>
|
||||
|
||||
<td height="19">As if an additional lock were added to the
|
||||
mutex.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td height="19">Checked</td>
|
||||
|
||||
<td height="19">Throws <a href="lock_error.html">
|
||||
lock_error</a>.</td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
<td height="19">Unspecified</td>
|
||||
|
||||
<td height="19">Undefined behavior [<a href=
|
||||
"bibliography.html#ISO">ISO</a> 1.3.12] (but typically, <a
|
||||
href="definitions.html#Deadlock">deadlock</a>.)</td>
|
||||
</tr>
|
||||
</table>
|
||||
|
||||
<p>If the associated mutex is not already locked by some other thread,
|
||||
locks the associated mutex and returns true, else returns false.</p>
|
||||
|
||||
<p><b>Returns:</b> See effects.</p>
|
||||
|
||||
<p><b>Throws:</b> <a href="lock_error.html">lock_error</a> if <code>
|
||||
locked()</code> or as indicated in <b>Effects</b>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>unlock</h3>
|
||||
<pre>
|
||||
void unlock();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Unlocks the associated mutex.</p>
|
||||
|
||||
<p><b>Throws:</b> <a href="lock_error.html">lock_error</a> if <code>
|
||||
!locked()</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>const void* Conversion</h3>
|
||||
<pre>
|
||||
operator const void*() const;
|
||||
</pre>
|
||||
|
||||
<p><b>Returns:</b> If the associated mutex is currently locked, a value
|
||||
convertible to <code>true</code>, else a value convertible to <code>
|
||||
false</code>.</p>
|
||||
|
||||
<p><b>Rationale:</b> A <code>const void*</code> conversion is
|
||||
considered safer than a conversion to <code>bool</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>locked</h3>
|
||||
<pre>
|
||||
bool locked() const;
|
||||
</pre>
|
||||
|
||||
<p><b>Returns:</b> <code>this->operator const void*() !=
|
||||
0</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h2><a name="Example">Example</a> Usage</h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/mutex.hpp"><boost/thread/mutex.hpp></a>
|
||||
#include <iostream>
|
||||
|
||||
int main(int, char*[])
|
||||
{
|
||||
boost::mutex mutex;
|
||||
boost::mutex::try_lock lock(mutex);
|
||||
if (lock)
|
||||
std::cout << "locked" << std::endl;
|
||||
else
|
||||
std::cout << "unlocked" << std::endl;
|
||||
return 0;
|
||||
}
|
||||
</pre>
|
||||
|
||||
<p>The output is:</p>
|
||||
<pre>
|
||||
locked
|
||||
</pre>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
4
doc/styles.css
Normal file
4
doc/styles.css
Normal file
@@ -0,0 +1,4 @@
|
||||
PRE
|
||||
{
|
||||
BACKGROUND-COLOR: lightcyan
|
||||
}
|
||||
506
doc/thread.html
506
doc/thread.html
@@ -1,94 +1,92 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - <boost/thread.hpp></title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Header <<a href="../../../boost/thread/thread.hpp">boost/thread.hpp</a>></h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<h2>Contents</h2>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#classes">Classes</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-thread">Class <code>thread</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-thread-synopsis">Class <code>thread</code> synopsis</a></dt>
|
||||
<dt><a href="#class-thread-ctors">Class <code>thread</code> constructors
|
||||
and destructor</a></dt>
|
||||
<dt><a href="#class-thread-comparisons">Class <code>thread</code> comparison
|
||||
functions</a></dt>
|
||||
<dt><a href="#class-thread-modifiers">Class <code>thread</code> modifier
|
||||
functions</a></dt>
|
||||
<dt><a href="#class-thread-statics">Class <code>thread</code> static functions</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#class-thread_group">Class <code>thread_group</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-thread_group-synopsis">Class <code>thread_group</code>
|
||||
synopsis</a></dt>
|
||||
<dt><a href="#class-thread_group-ctors">Class <code>thread_group</code>
|
||||
constructors and destructor</a></dt>
|
||||
<dt><a href="#class-thread_group-modifiers">Class <code>thread_group</code>
|
||||
modifier functions</a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
<dt><a href="#examples">Example(s)</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#example-thread">Simple usage of <code>boost::thread</code></a></dt>
|
||||
<dt><a href="#example-thread_group">Simple usage of <code>boost::thread_group</code></a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
<hr>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>The header <<a href="../../../boost/thread/thread.hpp">boost/thread.hpp</a>>
|
||||
defines the classes <a href="#class-thread">thread</a> and <a href="#class-thread_group">thread_group</a>
|
||||
which are used to create, observe and manage threads and groups of threads.</p>
|
||||
<h2><a name="classes"></a>Classes</h2>
|
||||
<h3><a name="class-thread"></a>Class <code>thread</code></h3>
|
||||
<p>The <code>thread</code> class represents threads of execution, and provides
|
||||
the functionality to create and manage threads within the <b> Boost.Threads</b>
|
||||
library. See <a href="definitions.html"> Definitions</a> for a precise description
|
||||
of "thread of execution", and for definitions of threading related
|
||||
terms and of thread states such as "blocked".</p>
|
||||
<p>A thread of execution has an initial function. For the program's initial
|
||||
thread, the initial function is <code>main()</code>. For other threads, the
|
||||
initial function is <code>operator()</code> of the function object passed to
|
||||
the class <code>thread</code> constructor.</p>
|
||||
<p>A thread of execution is said to be "finished" or "finished
|
||||
execution" when its initial function returns or is terminated. This includes
|
||||
completion of all thread cleanup handlers, and completion of the normal C++
|
||||
function return behaviors, such as destruction of automatic storage (stack)
|
||||
objects and releasing any associated implementation resources.</p>
|
||||
<p>A thread object has an associated state which is either "joinable"
|
||||
or "non-joinable".</p>
|
||||
<p>Except as described below, the policy used by an implementation of <b>Boost.Threads</b>
|
||||
to schedule transitions between thread states is unspecified.</p>
|
||||
<p><b>Note:</b> Just as the lifetime of a file may be different from the lifetime
|
||||
of an iostream object which represents the file, the lifetime of a thread of
|
||||
execution may be different from the <code> thread</code> object which represents
|
||||
the thread of execution. In particular, after a call to <code>join()</code>,
|
||||
the thread of execution will no longer exist even though the <code>thread</code>
|
||||
object continues to exist until the end of its normal lifetime. The converse
|
||||
is also possible; if a <code>thread</code> object is destroyed without <code>join()</code>
|
||||
having first been called, the thread of execution continues until its initial
|
||||
function completes.</p>
|
||||
<h4><a name="class-thread-synopsis"></a>Class <code>thread</code> synopsis</h4>
|
||||
<pre>namespace boost {
|
||||
class thread : <a href="../../utility/utility.htm#Class_noncopyable">boost::noncopyable</a> // Exposition only.
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content=
|
||||
"threads, Boost.Threads, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, thread</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#ffffff" link="#0000ff" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img height="86" alt="C++ Boost" src=
|
||||
"../../../c++boost.gif" width="277"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">Class thread</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#Synopsis">Synopsis</a><br>
|
||||
<a href="#Members">Members</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>The <code>thread</code> class represents threads of execution, and
|
||||
provides the functionality to create and manage threads within the <b>
|
||||
Boost.Threads</b> library. See <a href="definitions.html">
|
||||
Definitions</a> for a precise description of "thread of
|
||||
execution", and for definitions of threading related terms and of
|
||||
thread states such as "blocked".</p>
|
||||
|
||||
<p>A thread of execution has an initial function. For the program's
|
||||
initial thread, the initial function is <code>main()</code>. For other
|
||||
threads, the initial function is <code>operator()</code> of the
|
||||
function object passed to the class <code>thread</code>
|
||||
constructor.</p>
|
||||
|
||||
<p>A thread of execution is said to be "finished" or
|
||||
"finished execution" when its initial function returns or is
|
||||
terminated. This includes completion of all thread cleanup handlers,
|
||||
and completion of the normal C++ function return behaviors, such as
|
||||
destruction of automatic storage (stack) objects and releasing any
|
||||
associated implementation resources.</p>
|
||||
|
||||
<p>A thread object has an associated state which is either
|
||||
"joinable" or "non-joinable".</p>
|
||||
|
||||
<p>Except as described below, the policy used by an implementation of
|
||||
<b>Boost.Threads</b> to schedule transitions between thread states is
|
||||
unspecified.</p>
|
||||
|
||||
<p><b>Note:</b> Just as the lifetime of a file may be different from
|
||||
the lifetime of an iostream object which represents the file, the
|
||||
lifetime of a thread of execution may be different from the <code>
|
||||
thread</code> object which represents the thread of execution. In
|
||||
particular, after a call to <code>join()</code>, the thread of
|
||||
execution will no longer exist even though the <code>thread</code>
|
||||
object continues to exist until the end of its normal lifetime. The
|
||||
converse is also possible; if a <code>thread</code> object is destroyed
|
||||
without <code>join()</code> having first been called, the thread of
|
||||
execution continues until its initial function completes.</p>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/thread.hpp"><boost/thread/thread.hpp></a>
|
||||
</pre>
|
||||
|
||||
<h2><a name="Synopsis">Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost {
|
||||
|
||||
class thread : <a href=
|
||||
"../../utility/utility.htm#noncopyable">boost::noncopyable</a> // Exposition only.
|
||||
// Class thread meets the <a href=
|
||||
"overview.html#non-copyable">NonCopyable</a> requirement.
|
||||
"overview.html#NonCopyable">NonCopyable</a> requirement.
|
||||
{
|
||||
public:
|
||||
thread();
|
||||
@@ -103,199 +101,161 @@ public:
|
||||
static void sleep(const xtime& xt);
|
||||
static void yield();
|
||||
};
|
||||
} // namespace boost
|
||||
</pre>
|
||||
<h4><a name="class-thread-ctors"></a>Class <code>thread</code> constructors and
|
||||
destructor</h4>
|
||||
<pre>thread();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Constructs a <code>thread</code> object representing the
|
||||
current thread of execution.</dt>
|
||||
<dt><b>Postconditions:</b> <code>*this</code> is non-joinable.</dt>
|
||||
<dt><b>Danger:</b> <code>*this</code> is valid only within the current thread.</dt>
|
||||
</dl>
|
||||
<pre>thread(const <a href="../../function/index.html">boost::function0</a><void>& threadfunc);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Starts a new thread of execution and constructs a <code>thread</code>
|
||||
object representing it. Copies <code> threadfunc</code> (which in turn copies
|
||||
the function object wrapped by <code>threadfunc</code>) to an internal location
|
||||
which persists for the lifetime of the new thread of execution. Calls <code>operator()</code>
|
||||
on the copy of the <code>threadfunc</code> function object in the new thread
|
||||
of execution.</dt>
|
||||
<dt><b>Postconditions:</b> <code>*this</code> is joinable.</dt>
|
||||
<dt><b>Throws:</b> <code>boost::thread_resource_error</code> if a new thread
|
||||
of execution cannot be started.</dt>
|
||||
</dl>
|
||||
<pre>~Thread();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Destroys <code>*this</code>. The actual thread of execution
|
||||
may continue to execute after the <code>thread</code> object has been destroyed.</dt>
|
||||
<dt><b>Note:</b> If <code>*this</code> is joinable the actual thread of execution
|
||||
becomes "detached". Any resources used by the thread will be reclaimed
|
||||
when the thread of execution completes. To ensure such a thread of execution
|
||||
runs to completion before the <code> thread</code> object is destroyed, call
|
||||
<code>join()</code>.</dt>
|
||||
</dl>
|
||||
<h4><a name="class-thread-comparisons"></a>Class <code>thread</code> comparison
|
||||
functions</h4>
|
||||
<pre>bool operator==(const thread& rhs) const;
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> The thread is non-terminated or <code>*this</code> is joinable.</dt>
|
||||
<dt><b>Returns:</b> <code>true</code> if <code>*this</code> and <code> rhs</code>
|
||||
represent the same thread of execution.</dt>
|
||||
</dl>
|
||||
<pre>bool operator!=(const thread& rhs) const;
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> The thread is non-terminated or <code>*this</code> is joinable.</dt>
|
||||
<dt><b>Returns:</b> <code>!(*this==rhs)</code>.</dt>
|
||||
</dl>
|
||||
<h4><a name="class-thread-modifiers"></a>Class <code>thread</code> modifier functions</h4>
|
||||
<pre>void join();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> <code>*this</code> is joinable.</dt>
|
||||
<dt><b>Effects:</b> The current thread of execution blocks until the initial
|
||||
function of the thread of execution represented by <code> *this</code> finishes
|
||||
and all resources are reclaimed.</dt>
|
||||
<dt><b>Postconditions:</b> <code>*this</code> is non-joinable.</dt>
|
||||
<dt><b>Notes:</b> If <code>*this == thread()</code> the result is implementation
|
||||
defined. If the implementation doesn't detect this the result will be
|
||||
<a href="definitions.html#Deadlock"> deadlock</a>.</dt>
|
||||
</dl>
|
||||
<h4><a name="class-thread-statics"></a>Class <code>thread</code> static functions</h4>
|
||||
<pre>static void sleep(const <a href="xtime.html">xtime</a>& XT);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> The current thread of execution blocks until <code> XT</code>
|
||||
is reached.</dt>
|
||||
</dl>
|
||||
<pre>static void yield();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> The current thread of execution is placed in the "ready"
|
||||
state.</dt>
|
||||
<dt><b>Notes:</b> Allow the current thread to give up the rest of its time slice
|
||||
(or other scheduling quota) to another thread. Particularly useful in non-preemptive
|
||||
implementations.</dt>
|
||||
</dl>
|
||||
<h3><a name="class-thread_group"></a>Class <code>thread_group</code></h3>
|
||||
<p>The <tt>thread_group</tt> class provides a container for easy grouping of threads
|
||||
to simplify several common thread creation and management idioms.</p>
|
||||
<p>All <tt>thread_group</tt> member functions are <a href=
|
||||
"definitions.html#thread-safe">thread-safe</a>, except destruction.</p>
|
||||
<h4><a name="class-thread_group-synopsis"></a>Class <code>thread_group</code>
|
||||
synopsis</h4>
|
||||
<pre>namespace boost {
|
||||
class thread_group : <a href=
|
||||
"../../utility/utility.htm#Class_noncopyable">boost::noncopyable</a>
|
||||
{
|
||||
public:
|
||||
thread_group();
|
||||
~thread_group();
|
||||
|
||||
thread* create_thread(const boost::function0<void>& threadfunc);
|
||||
void add_thread(thread* thrd);
|
||||
void remove_thread(thread* thrd);
|
||||
void join_all();
|
||||
};
|
||||
} // namespace boost
|
||||
</pre>
|
||||
<h4><a name="class-thread_group-ctors"></a>Class <code>thread_group</code> constructors
|
||||
and destructor</h4>
|
||||
<pre>thread_group();
|
||||
|
||||
<h2><a name="Members">Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructors</h3>
|
||||
<pre>
|
||||
thread();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Constructs an empty <code>thread_group</code> container.</dt>
|
||||
</dl>
|
||||
<pre>~thread_group();
|
||||
|
||||
<p><b>Effects:</b> Constructs a <code>thread</code> object representing
|
||||
the current thread of execution.</p>
|
||||
|
||||
<p><b>Postcondition:</b> <code>*this</code> is non-joinable.</p>
|
||||
|
||||
<p><b>Danger:</b> <code>*this</code> is valid only within the current
|
||||
thread.</p>
|
||||
<pre>
|
||||
thread(const <a href=
|
||||
"../../function/index.html">boost::function0</a><void>& threadfunc);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Destroys each contained thread object. Destroys <code>*this</code>.</dt>
|
||||
<dt><b>Notes:</b> Behavior is undefined if another thread references *this during
|
||||
the execution of the destructor.</dt>
|
||||
</dl>
|
||||
<h4><a name="class-thread_group-modifiers"></a>Class <code>thread_group</code>
|
||||
modifier functions</h4>
|
||||
<pre>thread* create_thread(const boost::function0<void>& threadfunc);
|
||||
|
||||
<p><b>Effects:</b> Starts a new thread of execution and constructs a
|
||||
<code>thread</code> object representing it. Copies <code>
|
||||
threadfunc</code> (which in turn copies the function object wrapped by
|
||||
<code>threadfunc</code>) to an internal location which persists for the
|
||||
lifetime of the new thread of execution. Calls <code>operator()</code>
|
||||
on the copy of the <code>threadfunc</code> function object in the new
|
||||
thread of execution.</p>
|
||||
|
||||
<p><b>Postcondition:</b> <code>*this</code> is joinable.</p>
|
||||
|
||||
<p><b>Throws:</b> <code>boost::thread_resource_error</code> if a new
|
||||
thread of execution cannot be started.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~thread();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Creates a new <tt>thread</tt> object that executes <tt>threadfunc</tt>
|
||||
and adds it to the <tt>thread_group</tt> container object's list of managed
|
||||
<tt>thread</tt> objects.</dt>
|
||||
<dt><b>Returns:</b> Pointer to the newly created thread.</dt>
|
||||
</dl>
|
||||
<pre>void add_thread(thread* thrd);
|
||||
|
||||
<p><b>Effects:</b> Destroys <code>*this</code>. The actual thread of
|
||||
execution may continue to execute after the <code>thread</code> object
|
||||
has been destroyed.</p>
|
||||
|
||||
<p><b>Notes:</b> If <code>*this</code> is joinable the actual thread of
|
||||
execution becomes "detached". Any resources used by the
|
||||
thread will be reclaimed when the thread of execution completes. To
|
||||
ensure such a thread of execution runs to completion before the <code>
|
||||
thread</code> object is destroyed, call <code>join()</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Comparison Operators</h3>
|
||||
<pre>
|
||||
bool operator==(const thread& rhs);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Adds <tt>thrd</tt> to the <tt>thread_group</tt> object's
|
||||
list of managed <tt>thread</tt> objects. The <tt>thrd</tt> object must have
|
||||
been allocated via operator new and will be deleted when the group is destroyed.</dt>
|
||||
</dl>
|
||||
<pre>Void remove_thread(thread* thrd);
|
||||
|
||||
<p><b>Requires:</b> The thread is non-terminated or <code>*this</code>
|
||||
is joinable.</p>
|
||||
|
||||
<p><b>Returns:</b> <code>true</code> if <code>*this</code> and <code>
|
||||
rhs</code> represent the same thread of execution.</p>
|
||||
<pre>
|
||||
bool operator!=(const thread& rhs);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Removes <code>*this</code>'s list of managed <tt>thread</tt>
|
||||
objects.</dt>
|
||||
<dt><b>Throws:</b> ? if <tt>thrd</tt> is not it <code>*this</code>'s list
|
||||
of managed <tt>thread</tt> objects.</dt>
|
||||
</dl>
|
||||
<pre>Void join_all();
|
||||
|
||||
<p><b>Returns:</b> <code>!(*this==rhs)</code>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>join</h3>
|
||||
<pre>
|
||||
void join();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> Calls <code>join()</code> on each of the managed <tt>thread</tt>
|
||||
objects.</dt>
|
||||
</dl>
|
||||
<h2><a name="functions"></a>Functions</h2>
|
||||
<pre><a name="function-spec"></a>{{function}}
|
||||
|
||||
<p><b>Requires:</b> <code>*this</code> is joinable.</p>
|
||||
|
||||
<p><b>Effects:</b> The current thread of execution blocks until the
|
||||
initial function of the thread of execution represented by <code>
|
||||
*this</code> finishes and all resources are reclaimed.</p>
|
||||
|
||||
<p><b>Postcondition:</b> <code>*this</code> is non-joinable.</p>
|
||||
|
||||
<p><b>Note:</b> If <code>*this == thread()</code> the result is
|
||||
implementation defined. If the implementation doesn't detect this
|
||||
the result will be <a href="definitions.html#Deadlock">
|
||||
deadlock</a>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>sleep</h3>
|
||||
<pre>
|
||||
static void sleep(const <a href="xtime.html">xtime</a>& xt);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> {{text}}</dt>
|
||||
<dt><b>Effects:</b> {{text}}</dt>
|
||||
<dt><b>Postconditions:</b> {{text}}</dt>
|
||||
<dt><b>Returns:</b> {{text}}</dt>
|
||||
<dt><b>Throws:</b> {{text}}</dt>
|
||||
<dt><b>Complexity:</b> {{text}}</dt>
|
||||
<dt><b>Rationale:</b> {{text}}</dt>
|
||||
</dl>
|
||||
<h2><a name="objects"></a>Objects</h2>
|
||||
<p><a name="object-spec"></a>{{Object specifications}}</p>
|
||||
<h2><a name="examples"></a>Example(s)</h2>
|
||||
<h3><a name="example-thread"></a>Simple usage of <code>boost::thread</code></h3>
|
||||
<p><a href="../example/thread.cpp">libs/thread/example/thread.cpp</a></p>
|
||||
<p>The output is:</p>
|
||||
<pre>setting alarm for 5 seconds...
|
||||
|
||||
<p><b>Effects:</b> The current thread of execution blocks until <code>
|
||||
xt</code> is reached.</p>
|
||||
<hr>
|
||||
|
||||
<h3>yield</h3>
|
||||
<pre>
|
||||
static void yield();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> The current thread of execution is placed in the
|
||||
"ready" state.</p>
|
||||
|
||||
<p><b>Notes:</b> Allow the current thread to give up the rest of its
|
||||
time slice (or other scheduling quota) to another thread. Particularly
|
||||
useful in non-preemptive implementations.</p>
|
||||
<hr>
|
||||
|
||||
<h2><a name="Example">Example Usage</a></h2>
|
||||
<pre>
|
||||
#include <boost/thread/thread.hpp>
|
||||
#include <iostream>
|
||||
|
||||
struct thread_alarm
|
||||
{
|
||||
thread_alarm(int secs) : m_secs(secs) { }
|
||||
void operator()()
|
||||
{
|
||||
boost::xtime xt;
|
||||
boost::xtime_get(&xt, boost::TIME_UTC);
|
||||
xt.sec += m_secs;
|
||||
|
||||
boost::thread::sleep(xt);
|
||||
|
||||
std::cout << "alarm sounded..." << std::endl;
|
||||
}
|
||||
|
||||
int m_secs;
|
||||
};
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
int secs = 5;
|
||||
std::cout << "setting alarm for 5 seconds..." << std::endl;
|
||||
boost::thread thrd(thread_alarm(secs));
|
||||
thrd.join();
|
||||
}
|
||||
</pre>
|
||||
|
||||
<p>The output is:</p>
|
||||
<pre>
|
||||
setting alarm for 5 seconds...
|
||||
alarm sounded...
|
||||
</pre>
|
||||
<h3><a name="example-thread_group"></a>Simple usage of <code>boost::thread_group</code></h3>
|
||||
<p><a href="../example/thread_group.cpp">libs/thread/example/thread_group.cpp</a></p>
|
||||
<p>The output is:</p>
|
||||
<pre>count = 1
|
||||
count = 2
|
||||
count = 3
|
||||
count = 4
|
||||
count = 5
|
||||
count = 6
|
||||
count = 7
|
||||
count = 8
|
||||
count = 9
|
||||
count = 10
|
||||
</pre>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->09 January, 2003<!--webbot bot="Timestamp" endspan i-checksum="38582" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
182
doc/thread_group.html
Normal file
182
doc/thread_group.html
Normal file
@@ -0,0 +1,182 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, thread_group</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">thread_group</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#Synopsis">Synopsis</a><br>
|
||||
<a href="#Members">Members</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>The <tt>thread_group</tt> class provides a container for easy
|
||||
grouping of threads to simplify several common thread creation and
|
||||
management idioms.</p>
|
||||
|
||||
<p>All <tt>thread_group</tt> member functions are <a href=
|
||||
"definitions.html#thread-safe">thread-safe</a>, except destruction.</p>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/thread.hpp"><boost/thread/thread.hpp></a>
|
||||
</pre>
|
||||
|
||||
<h2><a name="Synopsis">Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
class thread_group : <a href=
|
||||
"../../utility/utility.htm#noncopyable">boost::noncopyable</a>
|
||||
{
|
||||
public:
|
||||
thread_group();
|
||||
~thread_group();
|
||||
|
||||
thread* create_thread(const boost::function0<void>& threadfunc);
|
||||
void add_thread(thread* thrd);
|
||||
void remove_thread(thread* thrd);
|
||||
void join_all();
|
||||
};
|
||||
}
|
||||
</pre>
|
||||
|
||||
<h2><a name="Members">Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
thread_group();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Constructs an empty <tt>thread_group</tt>
|
||||
container.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~thread_group();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Destroys each contained thread object. Destroys
|
||||
<code>*this</code>.</p>
|
||||
|
||||
<p><b>Notes:</b> Behavior is undefined if another thread references
|
||||
*this during the execution of the destructor.</p>
|
||||
<hr>
|
||||
|
||||
<h3>create_thread</h3>
|
||||
<pre>
|
||||
thread* create_thread(const boost::function0<void>& threadfunc);
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Creates a new <tt>thread</tt> object that executes
|
||||
<tt>threadfunc</tt> and adds it to the <tt>thread_group</tt> container
|
||||
object's list of managed <tt>thread</tt> objects.</p>
|
||||
|
||||
<p><b>Returns:</b> Pointer to the newly created thread.</p>
|
||||
<hr>
|
||||
|
||||
<h3>add_thread</h3>
|
||||
<pre>
|
||||
void add_thread(thread* thrd);
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Adds <tt>thrd</tt> to the <tt>thread_group</tt>
|
||||
object's list of managed <tt>thread</tt> objects. The <tt>thrd</tt>
|
||||
object must have been allocated via operator new and will be deleted
|
||||
when the group is destroyed.</p>
|
||||
<hr>
|
||||
|
||||
<h3>remove_thread</h3>
|
||||
<pre>
|
||||
void remove_thread(thread* thrd);
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Removes <code>*this</code>'s list of managed
|
||||
<tt>thread</tt> objects.</p>
|
||||
|
||||
<p><b>Throws:</b> ? if <tt>thrd</tt> is not it <code>*this</code>'s
|
||||
list of managed <tt>thread</tt> objects.</p>
|
||||
<hr>
|
||||
|
||||
<h3>join_all</h3>
|
||||
<pre>
|
||||
void join_all();
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> Calls <code>join()</code> on each of the managed
|
||||
<tt>thread</tt> objects.</p>
|
||||
<hr>
|
||||
|
||||
<h2><a name="Example">Example</a> Usage</h2>
|
||||
<pre>
|
||||
#include <boost/thread/thread.hpp>
|
||||
#include <iostream>
|
||||
|
||||
int count = 0;
|
||||
boost::mutex mutex;
|
||||
|
||||
void increment_count()
|
||||
{
|
||||
boost::mutex::lock lock(mutex);
|
||||
std::cout << "count = " << ++count << std::endl;
|
||||
}
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
boost::thread_group threads;
|
||||
for (int i = 0; i < 10; ++i)
|
||||
threads.create_thread(&increment_count);
|
||||
threads.join_all();
|
||||
}
|
||||
</pre>
|
||||
|
||||
<p>The output is:</p>
|
||||
<pre>
|
||||
count = 1
|
||||
count = 2
|
||||
count = 3
|
||||
count = 4
|
||||
count = 5
|
||||
count = 6
|
||||
count = 7
|
||||
count = 8
|
||||
count = 9
|
||||
count = 10
|
||||
</pre>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
78
doc/thread_resource_error.html
Normal file
78
doc/thread_resource_error.html
Normal file
@@ -0,0 +1,78 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content="threads, BTL, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, thread_resource_error</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0" width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">thread_resource_error</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#Synopsis">Synopsis</a><br>
|
||||
<a href="#Members">Members</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>The <code>thread_resource_error</code> class defines an exception
|
||||
type that is thrown by constructors in the <b>Boost.Threads</b> library
|
||||
when thread related resources can not be acquired. This does not
|
||||
include memory allocation failures which instead throw
|
||||
std::bad_alloc.</p>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/thread.hpp"><boost/thread/exceptions.hpp></a>
|
||||
</pre>
|
||||
|
||||
<h2><a name="Synopsis">Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
class thread_resource_error : public std::runtime_error
|
||||
{
|
||||
public:
|
||||
thread_resource_error();
|
||||
};
|
||||
}
|
||||
</pre>
|
||||
|
||||
<h2><a name="Members">Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
thread_resource_error();
|
||||
</pre>
|
||||
|
||||
<p>Constructs a <code>thread_resource_error</code> object.</p>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
223
doc/thread_specific_ptr.html
Normal file
223
doc/thread_specific_ptr.html
Normal file
@@ -0,0 +1,223 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content=
|
||||
"threads, Boost.Threads, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, thread_specific_ptr</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">thread_specific_ptr</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#Synopsis">Synopsis</a><br>
|
||||
<a href="#Members">Members</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>The <code>thread_specific_ptr</code> class defines an interface for
|
||||
using thread specific storage. Thread specific storage is data
|
||||
associated with individual threads and is often used to make operations
|
||||
<a href="definitions.html#Thread-safe">thread-safe</a> that rely on
|
||||
global data.</p>
|
||||
|
||||
<p>Template <code>thread_specific_ptr</code> stores a pointer to an
|
||||
object obtained via <code>new</code> on a thread-by-thread basis and
|
||||
calls delete on the contained pointer when the thread terminates. Each
|
||||
thread initially stores the null pointer in each <code>
|
||||
thread_specific_ptr</code> instance.</p>
|
||||
|
||||
<p>The template <code>thread_specific_ptr</code> is useful in the
|
||||
following cases:</p>
|
||||
|
||||
<ul>
|
||||
<li>An interface was original written assuming a single thread of
|
||||
control and is being ported to a multi-threaded environment.</li>
|
||||
|
||||
<li>Each thread of control invokes sequences of methods that share
|
||||
data that must be logically accessed through a globally visible
|
||||
access point, but are physically unique for each thread, instead of
|
||||
being explicitly passed.</li>
|
||||
</ul>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/tss.hpp"><boost/thread/tss.hpp></a>
|
||||
</pre>
|
||||
|
||||
<h2><a name="Synopsis">Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost {
|
||||
|
||||
template <typename T>
|
||||
class thread_specific_ptr : private boost::noncopyable // Exposition only.
|
||||
// Class thread_specific_ptr meets the <a href=
|
||||
"overview.html#NonCopyable">NonCopyable</a> requirement.
|
||||
{
|
||||
public:
|
||||
thread_specific_ptr();
|
||||
~thread_specific_ptr();
|
||||
|
||||
T* get() const;
|
||||
T* operator->() const;
|
||||
T& operator*() const;
|
||||
T* release();
|
||||
void reset(T* p=0);
|
||||
};
|
||||
|
||||
} // namespace boost
|
||||
</pre>
|
||||
|
||||
<h2><a name="Members">Members</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>Constructor</h3>
|
||||
<pre>
|
||||
thread_specific_ptr();
|
||||
</pre>
|
||||
|
||||
<p><b>Postconditions:</b> A thread specific storage has been reserved
|
||||
for use by *this in all threads, with each thread initially storing a
|
||||
null pointer.</p>
|
||||
|
||||
<p><b>Requires:</b> The expression <code>delete get()</code> is well
|
||||
formed.</p>
|
||||
|
||||
<p><b>Throws:</b> <code>boost::thread_resource_error</code> if the
|
||||
necessary resources can not be obtained.</p>
|
||||
|
||||
<p><b>Notes:</b> There is an implementation specific limit to the
|
||||
number of thread specific storage objects that can be created, and this
|
||||
limit may be small.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Destructor</h3>
|
||||
<pre>
|
||||
~thread_specific_ptr();
|
||||
</pre>
|
||||
|
||||
<p><b>Notes:</b> Does not destroy any data that may be stored in any
|
||||
thread's thread specific storage. For this reason you should not
|
||||
destroy a <code>thread_specific_ptr</code> object until you are certain
|
||||
there are no threads running that have made use of its thread specific
|
||||
storage.</p>
|
||||
<hr>
|
||||
|
||||
<h3>get</h3>
|
||||
<pre>
|
||||
T* get() const;
|
||||
</pre>
|
||||
|
||||
<p><b>Returns:</b> The object stored in thread specific storage for the
|
||||
current thread for *this.</p>
|
||||
|
||||
<p><b>Notes:</b> Each thread initially returns 0.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Smart Pointer Operations</h3>
|
||||
<pre>
|
||||
T* operator->() const;
|
||||
</pre>
|
||||
|
||||
<p><b>Returns:</b> <code>get()</code></p>
|
||||
<pre>
|
||||
T& operator*() const;
|
||||
</pre>
|
||||
|
||||
<p><b>Returns:</b> <code>get()</code></p>
|
||||
|
||||
<p><b>Requires:</b> <code>get() != 0</code></p>
|
||||
<hr>
|
||||
|
||||
<h3>Release</h3>
|
||||
<pre>
|
||||
T* release();
|
||||
</pre>
|
||||
|
||||
<p><b>Returns:</b> <code>get()</code></p>
|
||||
|
||||
<p><b>Postcondition:</b> *this holds the null pointer for the current
|
||||
thread.</p>
|
||||
<hr>
|
||||
|
||||
<h3>Reset</h3>
|
||||
<pre>
|
||||
void reset(T* p=0);
|
||||
</pre>
|
||||
|
||||
<p><b>Effects:</b> If <code>get()!= p</code> then <code>delete
|
||||
get()</code>.</p>
|
||||
|
||||
<p><b>Postconditions:</b> <code>*this</code> holds the pointer <code>
|
||||
p</code> for the current thread.</p>
|
||||
|
||||
<p><b>Notes:</b> The pointer will be deleted when the thread
|
||||
terminates.</p>
|
||||
<hr>
|
||||
|
||||
<h2><a name="Example">Example Usage</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/thread.hpp"><boost/thread/thread.hpp></a>
|
||||
#include <a href=
|
||||
"../../../boost/thread/tss.hpp"><boost/thread/tss.hpp></a>
|
||||
#include <cassert>
|
||||
|
||||
boost::thread_specific_ptr<int> value;
|
||||
|
||||
void increment()
|
||||
{
|
||||
int* p = value.get();
|
||||
++*p;
|
||||
}
|
||||
|
||||
void thread_proc()
|
||||
{
|
||||
value.reset(new int(0)); // initialize the thread's storage
|
||||
for (int i=0; i<10; ++i)
|
||||
{
|
||||
increment();
|
||||
int* p = value.get();
|
||||
assert(*p == i+1);
|
||||
}
|
||||
}
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
boost::thread_group threads;
|
||||
for (int i=0; i<5; ++i)
|
||||
threads.create_thread(&thread_proc);
|
||||
threads.join_all();
|
||||
}
|
||||
</pre>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
169
doc/tss.html
169
doc/tss.html
@@ -1,169 +0,0 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Header <boost/thread/tss.hpp></title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Header <<a href="../../../boost/thread/tss.hpp">boost/thread/tss.hpp</a>></h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<h2>Contents</h2>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#classes">Classes</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-thread_specific_ptr">Class <code>thread_specific_ptr</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-thread_specific_ptr-synopsis">Class <code>thread_specific_ptr</code>
|
||||
synopsis</a></dt>
|
||||
<dt><a href="#class-thread_specific_ptr-ctors">Class <code>thread_specific_ptr</code>
|
||||
constructors and destructor</a></dt>
|
||||
<dt><a href="#class-thread_specific_ptr-modifiers">Class <code>thread_specific_ptr</code>
|
||||
modifier functions</a></dt>
|
||||
<dt><a href="#class-thread_specific_ptr-observers">Class <code>thread_specific_ptr</code>
|
||||
observer functions</a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
<dt><a href="#examples">Example(s)</a></dt>
|
||||
</dl>
|
||||
<hr>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>The header <<a href="../../../boost/thread/tss.hpp">boost/thread/tss.hpp</a>>
|
||||
defines the class <a href="#class-thread_specific_ptr">thread_specific_ptr</a>
|
||||
which is used to manage data associated with specific thread instances.</p>
|
||||
<h2><a name="classes"></a>Classes</h2>
|
||||
<h3><a name="class-thread_specific_ptr"></a>Class <code>thread_specific_ptr</code></h3>
|
||||
<p>The <code>thread_specific_ptr</code> class defines an interface for using thread
|
||||
specific storage. Thread specific storage is data associated with individual
|
||||
threads and is often used to make operations <a href="definitions.html#Thread-safe">thread-safe</a>
|
||||
that rely on global data.</p>
|
||||
<p>Template <code>thread_specific_ptr</code> stores a pointer to an object obtained
|
||||
via <code>new</code> on a thread-by-thread basis and calls delete on the contained
|
||||
pointer when the thread terminates. Each thread initially stores the null pointer
|
||||
in each <code> thread_specific_ptr</code> instance.</p>
|
||||
<p>The template <code>thread_specific_ptr</code> is useful in the following cases:</p>
|
||||
<ul>
|
||||
<li>An interface was originally written assuming a single thread of control
|
||||
and is being ported to a multithreaded environment.</li>
|
||||
<li>Each thread of control invokes sequences of methods that share data that
|
||||
must be logically accessed through a globally visible access point, but are
|
||||
physically unique for each thread, instead of being explicitly passed.</li>
|
||||
</ul>
|
||||
<h4><a name="class-thread_specific_ptr-synopsis"></a>Class <code>thread_specific_ptr</code>
|
||||
synopsis</h4>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
template <typename T>
|
||||
class thread_specific_ptr : private boost::noncopyable // Exposition only.
|
||||
// Class thread_specific_ptr meets the <a href="overview.html#non-copyable">NonCopyable</a> requirement.
|
||||
{
|
||||
public:
|
||||
thread_specific_ptr();
|
||||
~thread_specific_ptr();
|
||||
|
||||
T* get() const;
|
||||
T* operator->() const;
|
||||
T& operator*() const;
|
||||
T* release();
|
||||
void reset(T* p=0);
|
||||
};
|
||||
};
|
||||
</pre>
|
||||
<h4><a name="class-thread_specific_ptr-ctors"></a>Class <code>thread_specific_ptr</code>
|
||||
constructors and destructor</h4>
|
||||
<pre>
|
||||
thread_specific_ptr();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> The expression <code>delete get()</code> is well formed.</dt>
|
||||
<dt><b>Postconditions:</b> A thread specific storage has been reserved for use
|
||||
by <code>*this</code> in all threads, with each thread initially storing a
|
||||
null pointer.</dt>
|
||||
<dt><b>Throws:</b> <code>boost::thread_resource_error</code> if the necessary
|
||||
resources can not be obtained.</dt>
|
||||
<dt><b>Note:</b> There is an implementation specific limit to the number of
|
||||
thread specific storage objects that can be created, and this limit may be
|
||||
small.</dt>
|
||||
</dl>
|
||||
<pre>
|
||||
~thread_specific_ptr();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Note:</b> Does not destroy any data that may be stored in any thread's
|
||||
thread specific storage. For this reason you should not destroy a <code>thread_specific_ptr</code>
|
||||
object until you are certain there are no threads running that have made use
|
||||
of its thread specific storage.</dt>
|
||||
</dl>
|
||||
<h4><a name="class-thread_specific_ptr-modifiers"></a>Class <code>thread_specific_ptr</code>
|
||||
modifier functions</h4>
|
||||
<pre>
|
||||
T* release();
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Postconditions:</b> <code>*this</code> holds the null pointer for the
|
||||
current thread.</dt>
|
||||
<dt><b>Returns:</b> <code>this->get()</code> prior to the call.</dt>
|
||||
</dl>
|
||||
<pre>
|
||||
void reset(T* p=0);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Effects:</b> If <code>this->get()!= p</code> then <code>delete this->get()</code>.
|
||||
</dt>
|
||||
<dt><b>Postconditions:</b> <code>*this</code> holds the pointer <code> p</code>
|
||||
for the current thread.</dt>
|
||||
<dt><b>Note:</b> The pointer will be deleted when the thread terminates.</dt>
|
||||
</dl>
|
||||
<h4><a name="class-thread_specific_ptr-observers"></a>Class <code>thread_specific_ptr</code>
|
||||
observer functions</h4>
|
||||
<pre>
|
||||
T* get() const;
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Returns:</b> The object stored in thread specific storage for the current
|
||||
thread for <code>*this</code>.</dt>
|
||||
<dt><b>Note:</b> Each thread initially returns 0.</dt>
|
||||
</dl>
|
||||
<pre>
|
||||
T* operator->() const;
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Returns:</b> <code>this-<get()</code>.</dt>
|
||||
</dl>
|
||||
<pre>
|
||||
T& operator*() const;
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Requires:</b> <code>this-<get() != 0</code></dt>
|
||||
<dt><b>Returns:</b> <code>this-<get()</code>.</dt>
|
||||
</dl>
|
||||
<h2><a name="examples"></a>Example(s)</h2>
|
||||
<p><a href="../example/tss.cpp">libs/thread/example/tss.cpp</a></p>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
</html>
|
||||
245
doc/xtime.html
245
doc/xtime.html
@@ -1,110 +1,147 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
|
||||
<link rel="stylesheet" type="text/css" href="../../../boost.css">
|
||||
<title>Boost.Threads - Header <boost/thread/xtime.hpp></title>
|
||||
</head>
|
||||
<body link="#0000ff" vlink="#800080">
|
||||
<table border="0" cellpadding="7" cellspacing="0" width="100%" summary=
|
||||
"header">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><a href="../../../index.htm"><img height="86" width="277" alt="C++ Boost" src="../../../c++boost.gif" border="0"></a></h3>
|
||||
</td>
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
<h2 align="center">Header <<a href="../../../boost/thread/xtime.hpp">boost/thread/xtime.hpp</a>></h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
<h2>Contents</h2>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#introduction">Introduction</a></dt>
|
||||
<dt><a href="#values">Values</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#value-spec">TIME_UTC</a></dt>
|
||||
</dl>
|
||||
<dt><a href="#classes">Classes</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-spec">Struct <code>xtime</code></a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#class-xtime-synopsis">Struct <code>xtime</code> synopsis</a></dt>
|
||||
</dl>
|
||||
</dl>
|
||||
<dt><a href="#functions">Functions</a></dt>
|
||||
<dl class="page-index">
|
||||
<dt><a href="#function-xtime_get"><code>xtime_get</code></a></dt>
|
||||
</dl>
|
||||
<dt><a href="#examples">Example(s)</a></dt>
|
||||
</dl>
|
||||
<hr>
|
||||
<h2><a name="introduction"></a>Introduction</h2>
|
||||
<p>The header <<a href="../../../boost/thread/xtime.hpp">boost/thread/xtime.hpp</a>>
|
||||
defines functions and data types used to perform high-resolution time operations.
|
||||
This is a temporary solution that will be replaced by a more robust time library
|
||||
once available in Boost.</p>
|
||||
<h2><a name="values"></a>Values</h2>
|
||||
<pre><a name="value-spec"></a>
|
||||
<head>
|
||||
<meta http-equiv="Content-Type" content=
|
||||
"text/html; charset=iso-8859-1">
|
||||
<meta name="keywords" content=
|
||||
"threads, Boost.Threads, thread library, C++">
|
||||
<link rel="stylesheet" type="text/css" href="styles.css">
|
||||
|
||||
<title>Boost.Threads, xtime</title>
|
||||
</head>
|
||||
|
||||
<body bgcolor="#FFFFFF" link="#0000FF" vlink="#800080">
|
||||
<table summary="header" border="0" cellpadding="7" cellspacing="0"
|
||||
width="100%">
|
||||
<tr>
|
||||
<td valign="top" width="300">
|
||||
<h3><img src="../../../c++boost.gif" alt="C++ Boost" width=
|
||||
"277" height="86"></h3>
|
||||
</td>
|
||||
|
||||
<td valign="top">
|
||||
<h1 align="center">Boost.Threads</h1>
|
||||
|
||||
<h2 align="center">xtime</h2>
|
||||
</td>
|
||||
</tr>
|
||||
</table>
|
||||
<hr>
|
||||
|
||||
<p><a href="#Introduction">Introduction</a><br>
|
||||
<a href="#Header">Header</a><br>
|
||||
<a href="#Synopsis">Synopsis</a><br>
|
||||
<a href="#Reference">Reference</a><br>
|
||||
<a href="#Example">Example</a></p>
|
||||
|
||||
<h2><a name="Introduction">Introduction</a></h2>
|
||||
|
||||
<p>The <code>xtime</code> type is used to represent a point on some
|
||||
time scale or a duration in time. This type may be proposed for the C
|
||||
standard by Markus Kuhn. <b>Boost.Threads</b> provides only a very
|
||||
minimal implementation of this proposal and it's expected that a
|
||||
full implementation will be provided in Boost as a separate library, at
|
||||
which time <b>Boost.Threads</b> will deprecate its implementation.</p>
|
||||
|
||||
<h2><a name="Header">Header</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/xtime.hpp"><boost/thread/xtime.hpp></a>
|
||||
</pre>
|
||||
|
||||
<h2><a name="Synopsis">Synopsis</a></h2>
|
||||
<pre>
|
||||
namespace boost {
|
||||
|
||||
enum
|
||||
{
|
||||
TIME_UTC
|
||||
TIME_UTC=1,
|
||||
};
|
||||
|
||||
struct xtime
|
||||
{
|
||||
#if defined(BOOST_NO_INT64_T)
|
||||
int_fast32_t sec;
|
||||
#else
|
||||
int_fast64_t sec;
|
||||
#endif
|
||||
int_fast32_t nsec;
|
||||
};
|
||||
|
||||
int xtime_get(struct xtime* xtp, int clock_type);
|
||||
|
||||
} // namespace boost
|
||||
</pre>
|
||||
|
||||
<h2><a name="Reference">Reference</a></h2>
|
||||
<hr>
|
||||
|
||||
<h3>TIME_UTC</h3>
|
||||
|
||||
<p>The clock type for Coordinated Universal Time (UTC). The epoch for
|
||||
this clock type is 1970-01-01 00:00:00. This is the only clock type
|
||||
supported by <b>Boost.Threads</b>.</p>
|
||||
<hr>
|
||||
|
||||
<h3>xtime</h3>
|
||||
<pre>
|
||||
struct xtime
|
||||
{
|
||||
#if defined(BOOST_NO_INT64_T)
|
||||
int_fast32_t sec;
|
||||
#else
|
||||
int_fast64_t sec;
|
||||
#endif
|
||||
int_fast32_t nsec;
|
||||
};
|
||||
</pre>
|
||||
|
||||
<p><b>sec</b> represents the whole seconds that have passed since the
|
||||
epoch.</p>
|
||||
|
||||
<p><b>nsec</b> represents the nanoseconds since <code>sec.</code></p>
|
||||
<hr>
|
||||
|
||||
<h3>xtime_get</h3>
|
||||
<pre>
|
||||
int xtime_get(struct xtime* xtp, int clock_type);
|
||||
</pre>
|
||||
|
||||
<p><b>Postcondition:</b> <code>xtp</code> represents the current point
|
||||
in time as a duration since the epoch specified by the <code>
|
||||
clock_type</code>.</p>
|
||||
|
||||
<p><b>Returns:</b> <code>clock_type</code> if successful, otherwise
|
||||
0.</p>
|
||||
|
||||
<p><b>Notes:</b> The resolution is implementation specific. For many
|
||||
implementations the best resolution of time is far more than one
|
||||
nanosecond, and even when the resolution is reasonably good, the
|
||||
latency of a call to <code>xtime_get()</code> may be significant. For
|
||||
maximum portability, avoid durations of less than one second.</p>
|
||||
<hr>
|
||||
|
||||
<h2><a name="Example">Example Usage</a></h2>
|
||||
<pre>
|
||||
#include <a href=
|
||||
"../../../boost/thread/thread.hpp"><boost/thread/thread.hpp></a>
|
||||
#include <a href=
|
||||
"../../../boost/thread/tss.hpp"><boost/thread/xtime.hpp></a>
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
boost::xtime xt;
|
||||
boost::xtime_get(&xt, boost::TIME_UTC);
|
||||
xt.sec += 1;
|
||||
boost::thread::sleep(xt); // Sleep for 1 second
|
||||
}
|
||||
</pre>
|
||||
<p>The clock type for Coordinated Universal Time (UTC). The epoch for this clock
|
||||
type is 1970-01-01 00:00:00. This is the only clock type supported by <b>Boost.Threads</b>.</p>
|
||||
<h2><a name="classes"></a>Classes</h2>
|
||||
<h3><a name="class-xtime"></a>Struct <code>xtime</code></h3>
|
||||
<p>The <code>xtime</code> type is used to represent a point on some time scale
|
||||
or a duration in time. This type may be proposed for the C standard by Markus
|
||||
Kuhn. <b>Boost.Threads</b> provides only a very minimal implementation of this
|
||||
proposal and it's expected that a full implementation (or some other time
|
||||
library) will be provided in Boost as a separate library, at which time <b>Boost.Threads</b>
|
||||
will deprecate its implementation.</p>
|
||||
<h4><a name="class-xtime-synopsis"></a>Struct <code>xtime</code> synopsis</h4>
|
||||
<pre>
|
||||
namespace boost
|
||||
{
|
||||
struct xtime
|
||||
{
|
||||
#if defined(BOOST_NO_INT64_T)
|
||||
int_fast32_t sec;
|
||||
#else
|
||||
int_fast64_t sec;
|
||||
#endif
|
||||
int_fast32_t nsec;
|
||||
};
|
||||
};
|
||||
</pre>
|
||||
<h2><a name="functions"></a>Functions</h2>
|
||||
<pre>
|
||||
<a name="function-xtime_get"></a>int xtime_get(struct xtime* xtp, int clock_type);
|
||||
</pre>
|
||||
<dl class="function-semantics">
|
||||
<dt><b>Postconditions:</b> <code>xtp</code> represents the current point in
|
||||
time as a duration since the epoch specified by the <code> clock_type</code>.</dt>
|
||||
<dt><b>Returns:</b> <code>clock_type</code> if successful, otherwise 0.</dt>
|
||||
<dt><b>Note:</b> The resolution is implementation specific. For many implementations
|
||||
the best resolution of time is far more than one nanosecond, and even when
|
||||
the resolution is reasonably good, the latency of a call to <code>xtime_get()</code>
|
||||
may be significant. For maximum portability, avoid durations of less than
|
||||
one second.</dt>
|
||||
</dl>
|
||||
<h2><a name="examples"></a>Example(s)</h2>
|
||||
<p><a href="../example/xtime.cpp">libs/thread/example/xtime.cpp</a></p>
|
||||
<hr>
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->
|
||||
05 November, 2001
|
||||
<!--webbot bot="Timestamp" endspan i-checksum="39359" -->
|
||||
</p>
|
||||
<p><i>© Copyright <a href="mailto:wekempf@cox.net">William E. Kempf</a> 2001-2002.
|
||||
All Rights Reserved.</i></p>
|
||||
<p>Permission to use, copy, modify, distribute and sell this software and its
|
||||
documentation for any purpose is hereby granted without fee, provided that the
|
||||
above copyright notice appear in all copies and that both that copyright notice
|
||||
and this permission notice appear in supporting documentation. William E. Kempf
|
||||
makes no representations about the suitability of this software for any purpose.
|
||||
It is provided "as is" without express or implied warranty.</p>
|
||||
</body>
|
||||
<hr>
|
||||
|
||||
<p>Revised
|
||||
<!--webbot bot="Timestamp" S-Type="EDITED" S-Format="%d %B, %Y" startspan -->05 November, 2001<!--webbot bot="Timestamp" endspan i-checksum="39359" --></p>
|
||||
|
||||
<p><i>© Copyright <a href="mailto:williamkempf@hotmail.com">
|
||||
William E. Kempf</a> 2001 all rights reserved.</i></p>
|
||||
</body>
|
||||
</html>
|
||||
|
||||
|
||||
@@ -1,2 +0,0 @@
|
||||
bin
|
||||
*.pdb
|
||||
101
example/Jamfile
101
example/Jamfile
@@ -1,49 +1,66 @@
|
||||
# (C) Copyright William E. Kempf 2001. Permission to copy, use, modify, sell
|
||||
# and distribute this software is granted provided this copyright notice
|
||||
# appears in all copies. This software is provided "as is" without express or
|
||||
# implied warranty, and with no claim as to its suitability for any purpose.
|
||||
# (C) Copyright William E. Kempf 2001. Permission to copy, use, modify, sell and
|
||||
# distribute this software is granted provided this copyright notice appears
|
||||
# in all copies. This software is provided "as is" without express or implied
|
||||
# warranty, and with no claim as to its suitability for any purpose.
|
||||
#
|
||||
# Boost.Threads example Jamfile
|
||||
# Boost.Threads build and test Jamfile
|
||||
#
|
||||
# Additional configuration variables used:
|
||||
# 1. PTW32 may be used on Win32 platforms to specify that the pthreads-win32
|
||||
# library should be used instead of "native" threads. This feature is
|
||||
# mostly used for testing and it's generally recommended you use the
|
||||
# native threading libraries instead. PTW32 should be set to be a list
|
||||
# of two strings, the first specifying the installation path of the
|
||||
# pthreads-win32 library and the second specifying which library
|
||||
# variant to link against (see the pthreads-win32 documentation).
|
||||
# Example: jam -sPTW32="c:\pthreads-win32 pthreadVCE.lib"
|
||||
# Declares the following targets:
|
||||
# 1. monitor, an example program.
|
||||
# 2. starvephil, an example program.
|
||||
# 3. tennis, an example program.
|
||||
|
||||
# Declare the location of this subproject relative to the root.
|
||||
# declare the location of this subproject relative to the root
|
||||
subproject libs/thread/example ;
|
||||
|
||||
# Include threads.jam for Boost.Threads global build information.
|
||||
# This greatly simplifies the Jam code needed to configure the build
|
||||
# for the various Win32 build types.
|
||||
SEARCH on <module@>threads.jam = $(BOOST_ROOT)/libs/thread/build ;
|
||||
include <module@>threads.jam ;
|
||||
|
||||
# Do some OS-specific setup
|
||||
if $(NT)
|
||||
{
|
||||
template example
|
||||
## sources ##
|
||||
: <template>thread_base
|
||||
<dll>../build/boost_thread
|
||||
## requirements ##
|
||||
:
|
||||
## default build ##
|
||||
:
|
||||
;
|
||||
|
||||
exe monitor : <template>example monitor.cpp ;
|
||||
exe starvephil : <template>example starvephil.cpp ;
|
||||
exe tennis : <template>example tennis.cpp ;
|
||||
exe condition : <template>example condition.cpp ;
|
||||
exe mutex : <template>example mutex.cpp ;
|
||||
exe once : <template>example once.cpp ;
|
||||
exe recursive_mutex : <template>example recursive_mutex.cpp ;
|
||||
exe thread : <template>example thread.cpp ;
|
||||
exe thread_group : <template>example thread_group.cpp ;
|
||||
exe tss : <template>example tss.cpp ;
|
||||
exe xtime : <template>example xtime.cpp ;
|
||||
BOOST_THREADMON_LIB = <lib>../build/libboost_threadmon ;
|
||||
}
|
||||
else
|
||||
{
|
||||
BOOST_THREADMON_LIB = ;
|
||||
}
|
||||
|
||||
#######################
|
||||
|
||||
#
|
||||
# Declare the Boost.Threads monitor example program.
|
||||
#
|
||||
|
||||
exe monitor : monitor/monitor.cpp
|
||||
<lib>../build/libboost_thread
|
||||
$(BOOST_THREADMON_LIB)
|
||||
# requirements
|
||||
: <include>$(BOOST_ROOT)
|
||||
<threading>multi
|
||||
: debug release ;
|
||||
|
||||
#######################
|
||||
|
||||
#
|
||||
# Declare the Boost.Threads starvephil example program.
|
||||
#
|
||||
|
||||
exe starvephil : starvephil/starvephil.cpp
|
||||
<lib>../build/libboost_thread
|
||||
$(BOOST_THREADMON_LIB)
|
||||
# requirements
|
||||
: <include>$(BOOST_ROOT)
|
||||
<threading>multi
|
||||
: debug release ;
|
||||
|
||||
#######################
|
||||
|
||||
#
|
||||
# Declare the Boost.Threads tennis example program.
|
||||
#
|
||||
|
||||
exe tennis : tennis/tennis.cpp
|
||||
<lib>../build/libboost_thread
|
||||
$(BOOST_THREADMON_LIB)
|
||||
# requirements
|
||||
: <include>$(BOOST_ROOT)
|
||||
<threading>multi
|
||||
: debug release ;
|
||||
|
||||
@@ -1,5 +0,0 @@
|
||||
|
||||
exe starvephil
|
||||
: starvephil.cpp ../build/boost_thread ../../test/build/unit_test_framework
|
||||
;
|
||||
|
||||
@@ -1,79 +0,0 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#include <iostream>
|
||||
#include <vector>
|
||||
#include <boost/utility.hpp>
|
||||
#include <boost/thread/condition.hpp>
|
||||
#include <boost/thread/thread.hpp>
|
||||
|
||||
class bounded_buffer : private boost::noncopyable
|
||||
{
|
||||
public:
|
||||
typedef boost::mutex::scoped_lock lock;
|
||||
|
||||
bounded_buffer(int n) : begin(0), end(0), buffered(0), circular_buf(n) { }
|
||||
|
||||
void send (int m) {
|
||||
lock lk(monitor);
|
||||
while (buffered == circular_buf.size())
|
||||
buffer_not_full.wait(lk);
|
||||
circular_buf[end] = m;
|
||||
end = (end+1) % circular_buf.size();
|
||||
++buffered;
|
||||
buffer_not_empty.notify_one();
|
||||
}
|
||||
int receive() {
|
||||
lock lk(monitor);
|
||||
while (buffered == 0)
|
||||
buffer_not_empty.wait(lk);
|
||||
int i = circular_buf[begin];
|
||||
begin = (begin+1) % circular_buf.size();
|
||||
--buffered;
|
||||
buffer_not_full.notify_one();
|
||||
return i;
|
||||
}
|
||||
|
||||
private:
|
||||
int begin, end, buffered;
|
||||
std::vector<int> circular_buf;
|
||||
boost::condition buffer_not_full, buffer_not_empty;
|
||||
boost::mutex monitor;
|
||||
};
|
||||
|
||||
bounded_buffer buf(2);
|
||||
|
||||
void sender() {
|
||||
int n = 0;
|
||||
while (n < 100) {
|
||||
buf.send(n);
|
||||
std::cout << "sent: " << n << std::endl;
|
||||
++n;
|
||||
}
|
||||
buf.send(-1);
|
||||
}
|
||||
|
||||
void receiver() {
|
||||
int n;
|
||||
do {
|
||||
n = buf.receive();
|
||||
std::cout << "received: " << n << std::endl;
|
||||
} while (n != -1); // -1 indicates end of buffer
|
||||
}
|
||||
|
||||
int main(int, char*[])
|
||||
{
|
||||
boost::thread thrd1(&sender);
|
||||
boost::thread thrd2(&receiver);
|
||||
thrd1.join();
|
||||
thrd2.join();
|
||||
return 0;
|
||||
}
|
||||
@@ -1,14 +1,3 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#include <vector>
|
||||
#include <iostream>
|
||||
#include <boost/thread/condition.hpp>
|
||||
@@ -17,23 +6,21 @@
|
||||
#include <boost/thread/thread.hpp>
|
||||
|
||||
namespace {
|
||||
|
||||
const int ITERS = 100;
|
||||
boost::mutex io_mutex;
|
||||
|
||||
} // namespace
|
||||
const int ITERS = 100;
|
||||
boost::mutex io_mutex;
|
||||
};
|
||||
|
||||
template <typename M>
|
||||
class buffer_t
|
||||
{
|
||||
public:
|
||||
typedef typename M::scoped_lock scoped_lock;
|
||||
|
||||
|
||||
buffer_t(int n)
|
||||
: p(0), c(0), full(0), buf(n)
|
||||
{
|
||||
}
|
||||
|
||||
|
||||
void send(int m)
|
||||
{
|
||||
scoped_lock lk(mutex);
|
||||
@@ -42,7 +29,7 @@ public:
|
||||
buf[p] = m;
|
||||
p = (p+1) % buf.size();
|
||||
++full;
|
||||
cond.notify_one();
|
||||
cond.notify_all();
|
||||
}
|
||||
int receive()
|
||||
{
|
||||
@@ -52,40 +39,41 @@ public:
|
||||
int i = buf[c];
|
||||
c = (c+1) % buf.size();
|
||||
--full;
|
||||
cond.notify_one();
|
||||
cond.notify_all();
|
||||
return i;
|
||||
}
|
||||
|
||||
|
||||
static buffer_t& get_buffer()
|
||||
{
|
||||
static buffer_t buf(2);
|
||||
return buf;
|
||||
}
|
||||
|
||||
|
||||
static void do_sender_thread()
|
||||
{
|
||||
for (int n = 0; n < ITERS; ++n)
|
||||
{
|
||||
get_buffer().send(n);
|
||||
{
|
||||
boost::mutex::scoped_lock lock(io_mutex);
|
||||
std::cout << "sending: " << n << std::endl;
|
||||
std::cout << "sent: " << n << std::endl;
|
||||
}
|
||||
get_buffer().send(n);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
static void do_receiver_thread()
|
||||
{
|
||||
for (int x=0; x < (ITERS/2); ++x)
|
||||
int n;
|
||||
do
|
||||
{
|
||||
int n = get_buffer().receive();
|
||||
n = get_buffer().receive();
|
||||
{
|
||||
boost::mutex::scoped_lock lock(io_mutex);
|
||||
std::cout << "received: " << n << std::endl;
|
||||
}
|
||||
}
|
||||
} while (n < ITERS - 1);
|
||||
}
|
||||
|
||||
|
||||
private:
|
||||
M mutex;
|
||||
boost::condition cond;
|
||||
@@ -98,12 +86,10 @@ void do_test(M* dummy=0)
|
||||
{
|
||||
typedef buffer_t<M> buffer_type;
|
||||
buffer_type::get_buffer();
|
||||
boost::thread thrd1(&buffer_type::do_receiver_thread);
|
||||
boost::thread thrd1(&buffer_type::do_sender_thread);
|
||||
boost::thread thrd2(&buffer_type::do_receiver_thread);
|
||||
boost::thread thrd3(&buffer_type::do_sender_thread);
|
||||
thrd1.join();
|
||||
thrd2.join();
|
||||
thrd3.join();
|
||||
}
|
||||
|
||||
void test_buffer()
|
||||
@@ -1,52 +0,0 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#include <boost/thread/mutex.hpp>
|
||||
#include <boost/thread/thread.hpp>
|
||||
#include <iostream>
|
||||
|
||||
boost::mutex io_mutex; // The iostreams are not guaranteed to be thread-safe!
|
||||
|
||||
class counter
|
||||
{
|
||||
public:
|
||||
counter() : count(0) { }
|
||||
|
||||
int increment() {
|
||||
boost::mutex::scoped_lock scoped_lock(mutex);
|
||||
return ++count;
|
||||
}
|
||||
|
||||
private:
|
||||
boost::mutex mutex;
|
||||
int count;
|
||||
};
|
||||
|
||||
counter c;
|
||||
|
||||
void change_count()
|
||||
{
|
||||
int i = c.increment();
|
||||
boost::mutex::scoped_lock scoped_lock(io_mutex);
|
||||
std::cout << "count == " << i << std::endl;
|
||||
}
|
||||
|
||||
int main(int, char*[])
|
||||
{
|
||||
const int num_threads = 4;
|
||||
boost::thread_group thrds;
|
||||
for (int i=0; i < num_threads; ++i)
|
||||
thrds.create_thread(&change_count);
|
||||
|
||||
thrds.join_all();
|
||||
|
||||
return 0;
|
||||
}
|
||||
@@ -1,36 +0,0 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#include <boost/thread/thread.hpp>
|
||||
#include <boost/thread/once.hpp>
|
||||
#include <cassert>
|
||||
|
||||
int value=0;
|
||||
boost::once_flag once = BOOST_ONCE_INIT;
|
||||
|
||||
void init()
|
||||
{
|
||||
++value;
|
||||
}
|
||||
|
||||
void thread_proc()
|
||||
{
|
||||
boost::call_once(&init, once);
|
||||
}
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
boost::thread_group threads;
|
||||
for (int i=0; i<5; ++i)
|
||||
threads.create_thread(&thread_proc);
|
||||
threads.join_all();
|
||||
assert(value == 1);
|
||||
}
|
||||
@@ -1,54 +0,0 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#include <boost/thread/recursive_mutex.hpp>
|
||||
#include <boost/thread/thread.hpp>
|
||||
#include <iostream>
|
||||
|
||||
class counter
|
||||
{
|
||||
public:
|
||||
counter() : count(0) { }
|
||||
|
||||
int add(int val) {
|
||||
boost::recursive_mutex::scoped_lock scoped_lock(mutex);
|
||||
count += val;
|
||||
return count;
|
||||
}
|
||||
int increment() {
|
||||
boost::recursive_mutex::scoped_lock scoped_lock(mutex);
|
||||
return add(1);
|
||||
}
|
||||
|
||||
private:
|
||||
boost::recursive_mutex mutex;
|
||||
int count;
|
||||
};
|
||||
|
||||
counter c;
|
||||
|
||||
void change_count()
|
||||
{
|
||||
std::cout << "count == " << c.increment() << std::endl;
|
||||
}
|
||||
|
||||
int main(int, char*[])
|
||||
{
|
||||
const int num_threads=4;
|
||||
|
||||
boost::thread_group threads;
|
||||
for (int i=0; i < num_threads; ++i)
|
||||
threads.create_thread(&change_count);
|
||||
|
||||
threads.join_all();
|
||||
|
||||
return 0;
|
||||
}
|
||||
@@ -1,191 +0,0 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#include <boost/thread/mutex.hpp>
|
||||
#include <boost/thread/condition.hpp>
|
||||
#include <boost/thread/thread.hpp>
|
||||
#include <boost/thread/xtime.hpp>
|
||||
#include <iostream>
|
||||
#include <time.h>
|
||||
|
||||
namespace {
|
||||
|
||||
boost::mutex iomx;
|
||||
|
||||
}
|
||||
|
||||
class canteen
|
||||
{
|
||||
public:
|
||||
canteen() : m_chickens(0) { }
|
||||
|
||||
void get(int id)
|
||||
{
|
||||
boost::mutex::scoped_lock lock(m_mutex);
|
||||
while (m_chickens == 0)
|
||||
{
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Phil" << id <<
|
||||
": wot, no chickens? I'll WAIT ..." << std::endl;
|
||||
}
|
||||
m_condition.wait(lock);
|
||||
}
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Phil" << id <<
|
||||
": those chickens look good ... one please ..." << std::endl;
|
||||
}
|
||||
m_chickens--;
|
||||
}
|
||||
void put(int value)
|
||||
{
|
||||
boost::mutex::scoped_lock lock(m_mutex);
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock()
|
||||
<< ") Chef: ouch ... make room ... this dish is "
|
||||
<< "very hot ..." << std::endl;
|
||||
}
|
||||
boost::xtime xt;
|
||||
boost::xtime_get(&xt, boost::TIME_UTC);
|
||||
xt.sec += 3;
|
||||
boost::thread::sleep(xt);
|
||||
m_chickens += value;
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() <<
|
||||
") Chef: more chickens ... " << m_chickens <<
|
||||
" now available ... NOTIFYING ..." << std::endl;
|
||||
}
|
||||
m_condition.notify_all();
|
||||
}
|
||||
|
||||
private:
|
||||
boost::mutex m_mutex;
|
||||
boost::condition m_condition;
|
||||
int m_chickens;
|
||||
};
|
||||
|
||||
canteen g_canteen;
|
||||
|
||||
void chef()
|
||||
{
|
||||
const int chickens = 4;
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Chef: starting ..." << std::endl;
|
||||
}
|
||||
for (;;)
|
||||
{
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Chef: cooking ..." << std::endl;
|
||||
}
|
||||
boost::xtime xt;
|
||||
boost::xtime_get(&xt, boost::TIME_UTC);
|
||||
xt.sec += 2;
|
||||
boost::thread::sleep(xt);
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Chef: " << chickens
|
||||
<< " chickens, ready-to-go ..." << std::endl;
|
||||
}
|
||||
g_canteen.put(chickens);
|
||||
}
|
||||
}
|
||||
|
||||
struct phil
|
||||
{
|
||||
phil(int id) : m_id(id) { }
|
||||
void run() {
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Phil" << m_id
|
||||
<< ": starting ..." << std::endl;
|
||||
}
|
||||
for (;;)
|
||||
{
|
||||
if (m_id > 0)
|
||||
{
|
||||
boost::xtime xt;
|
||||
boost::xtime_get(&xt, boost::TIME_UTC);
|
||||
xt.sec += 3;
|
||||
boost::thread::sleep(xt);
|
||||
}
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Phil" << m_id
|
||||
<< ": gotta eat ..." << std::endl;
|
||||
}
|
||||
g_canteen.get(m_id);
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Phil" << m_id
|
||||
<< ": mmm ... that's good ..." << std::endl;
|
||||
}
|
||||
}
|
||||
}
|
||||
static void do_thread(void* param) {
|
||||
static_cast<phil*>(param)->run();
|
||||
}
|
||||
|
||||
int m_id;
|
||||
};
|
||||
|
||||
struct thread_adapt
|
||||
{
|
||||
thread_adapt(void (*func)(void*), void* param)
|
||||
: _func(func), _param(param)
|
||||
{
|
||||
}
|
||||
int operator()() const
|
||||
{
|
||||
_func(_param);
|
||||
return 0;
|
||||
}
|
||||
|
||||
void (*_func)(void*);
|
||||
void* _param;
|
||||
};
|
||||
|
||||
class thread_adapter
|
||||
{
|
||||
public:
|
||||
thread_adapter(void (*func)(void*), void* param)
|
||||
: _func(func), _param(param)
|
||||
{
|
||||
}
|
||||
void operator()() const { _func(_param); }
|
||||
private:
|
||||
void (*_func)(void*);
|
||||
void* _param;
|
||||
};
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
boost::thread thrd_chef(&chef);
|
||||
phil p[] = { phil(0), phil(1), phil(2), phil(3), phil(4) };
|
||||
boost::thread thrd_phil0(thread_adapter(&phil::do_thread, &p[0]));
|
||||
boost::thread thrd_phil1(thread_adapter(&phil::do_thread, &p[1]));
|
||||
boost::thread thrd_phil2(thread_adapter(&phil::do_thread, &p[2]));
|
||||
boost::thread thrd_phil3(thread_adapter(&phil::do_thread, &p[3]));
|
||||
boost::thread thrd_phil4(thread_adapter(&phil::do_thread, &p[4]));
|
||||
|
||||
thrd_chef.join();
|
||||
thrd_phil0.join();
|
||||
thrd_phil1.join();
|
||||
thrd_phil2.join();
|
||||
thrd_phil3.join();
|
||||
thrd_phil4.join();
|
||||
|
||||
return 0;
|
||||
}
|
||||
171
example/starvephil/starvephil.cpp
Normal file
171
example/starvephil/starvephil.cpp
Normal file
@@ -0,0 +1,171 @@
|
||||
#include <boost/thread/mutex.hpp>
|
||||
#include <boost/thread/condition.hpp>
|
||||
#include <boost/thread/thread.hpp>
|
||||
#include <boost/thread/xtime.hpp>
|
||||
#include <iostream>
|
||||
#include <time.h>
|
||||
|
||||
namespace
|
||||
{
|
||||
boost::mutex iomx;
|
||||
};
|
||||
|
||||
class canteen
|
||||
{
|
||||
public:
|
||||
canteen() : m_chickens(0) { }
|
||||
|
||||
void get(int id)
|
||||
{
|
||||
boost::mutex::scoped_lock lock(m_mutex);
|
||||
while (m_chickens == 0)
|
||||
{
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Phil" << id <<
|
||||
": wot, no chickens? I'll WAIT ..." << std::endl;
|
||||
}
|
||||
m_condition.wait(lock);
|
||||
}
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Phil" << id <<
|
||||
": those chickens look good ... one please ..." << std::endl;
|
||||
}
|
||||
m_chickens--;
|
||||
}
|
||||
void put(int value)
|
||||
{
|
||||
boost::mutex::scoped_lock lock(m_mutex);
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() <<
|
||||
") Chef: ouch ... make room ... this dish is very hot ..." << std::endl;
|
||||
}
|
||||
boost::xtime xt;
|
||||
boost::xtime_get(&xt, boost::TIME_UTC);
|
||||
xt.sec += 3;
|
||||
boost::thread::sleep(xt);
|
||||
m_chickens += value;
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() <<
|
||||
") Chef: more chickens ... " << m_chickens <<
|
||||
" now available ... NOTIFYING ..." << std::endl;
|
||||
}
|
||||
m_condition.notify_all();
|
||||
}
|
||||
|
||||
private:
|
||||
boost::mutex m_mutex;
|
||||
boost::condition m_condition;
|
||||
int m_chickens;
|
||||
};
|
||||
|
||||
canteen g_canteen;
|
||||
|
||||
void chef()
|
||||
{
|
||||
const int chickens = 4;
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Chef: starting ..." << std::endl;
|
||||
}
|
||||
for (;;)
|
||||
{
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Chef: cooking ..." << std::endl;
|
||||
}
|
||||
boost::xtime xt;
|
||||
boost::xtime_get(&xt, boost::TIME_UTC);
|
||||
xt.sec += 2;
|
||||
boost::thread::sleep(xt);
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Chef: " << chickens
|
||||
<< " chickens, ready-to-go ..." << std::endl;
|
||||
}
|
||||
g_canteen.put(chickens);
|
||||
}
|
||||
}
|
||||
|
||||
struct phil
|
||||
{
|
||||
phil(int id) : m_id(id) { }
|
||||
void run() {
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Phil" << m_id << ": starting ..." << std::endl;
|
||||
}
|
||||
for (;;)
|
||||
{
|
||||
if (m_id > 0)
|
||||
{
|
||||
boost::xtime xt;
|
||||
boost::xtime_get(&xt, boost::TIME_UTC);
|
||||
xt.sec += 3;
|
||||
boost::thread::sleep(xt);
|
||||
}
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Phil" << m_id
|
||||
<< ": gotta eat ..." << std::endl;
|
||||
}
|
||||
g_canteen.get(m_id);
|
||||
{
|
||||
boost::mutex::scoped_lock lock(iomx);
|
||||
std::cout << "(" << clock() << ") Phil" << m_id
|
||||
<< ": mmm ... that's good ..." << std::endl;
|
||||
}
|
||||
}
|
||||
}
|
||||
static void do_thread(void* param) {
|
||||
static_cast<phil*>(param)->run();
|
||||
}
|
||||
|
||||
int m_id;
|
||||
};
|
||||
|
||||
struct thread_adapt
|
||||
{
|
||||
thread_adapt(void (*func)(void*), void* param) : _func(func), _param(param) { }
|
||||
int operator()() const
|
||||
{
|
||||
_func(_param);
|
||||
return 0;
|
||||
}
|
||||
|
||||
void (*_func)(void*);
|
||||
void* _param;
|
||||
};
|
||||
|
||||
class thread_adapter
|
||||
{
|
||||
public:
|
||||
thread_adapter(void (*func)(void*), void* param) : _func(func), _param(param) { }
|
||||
void operator()() const { _func(_param); }
|
||||
private:
|
||||
void (*_func)(void*);
|
||||
void* _param;
|
||||
};
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
boost::thread thrd_chef(&chef);
|
||||
phil p[] = { phil(0), phil(1), phil(2), phil(3), phil(4) };
|
||||
boost::thread thrd_phil0(thread_adapter(&phil::do_thread, &p[0]));
|
||||
boost::thread thrd_phil1(thread_adapter(&phil::do_thread, &p[1]));
|
||||
boost::thread thrd_phil2(thread_adapter(&phil::do_thread, &p[2]));
|
||||
boost::thread thrd_phil3(thread_adapter(&phil::do_thread, &p[3]));
|
||||
boost::thread thrd_phil4(thread_adapter(&phil::do_thread, &p[4]));
|
||||
|
||||
thrd_chef.join();
|
||||
thrd_phil0.join();
|
||||
thrd_phil1.join();
|
||||
thrd_phil2.join();
|
||||
thrd_phil3.join();
|
||||
thrd_phil4.join();
|
||||
|
||||
return 0;
|
||||
}
|
||||
@@ -1,14 +1,3 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#include <boost/thread/mutex.hpp>
|
||||
#include <boost/thread/condition.hpp>
|
||||
#include <boost/thread/thread.hpp>
|
||||
@@ -16,8 +5,8 @@
|
||||
#include <iostream>
|
||||
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
# include <windows.h>
|
||||
# include <process.h>
|
||||
# include <windows.h>
|
||||
# include <process.h>
|
||||
#endif
|
||||
|
||||
enum game_state
|
||||
@@ -60,8 +49,7 @@ void player(void* param)
|
||||
{
|
||||
cond.wait(lock);
|
||||
if (state == other)
|
||||
std::cout << "---" << player_name(active)
|
||||
<< ": Spurious wakeup!" << std::endl;
|
||||
std::cout << "---" << player_name(active) << ": Spurious wakeup!" << std::endl;
|
||||
} while (state == other);
|
||||
}
|
||||
|
||||
@@ -72,10 +60,7 @@ void player(void* param)
|
||||
|
||||
struct thread_adapt
|
||||
{
|
||||
thread_adapt(void (*func)(void*), void* param)
|
||||
: _func(func), _param(param)
|
||||
{
|
||||
}
|
||||
thread_adapt(void (*func)(void*), void* param) : _func(func), _param(param) { }
|
||||
int operator()() const
|
||||
{
|
||||
_func(_param);
|
||||
@@ -89,10 +74,7 @@ struct thread_adapt
|
||||
class thread_adapter
|
||||
{
|
||||
public:
|
||||
thread_adapter(void (*func)(void*), void* param)
|
||||
: _func(func), _param(param)
|
||||
{
|
||||
}
|
||||
thread_adapter(void (*func)(void*), void* param) : _func(func), _param(param) { }
|
||||
void operator()() const { _func(_param); }
|
||||
private:
|
||||
void (*_func)(void*);
|
||||
@@ -1,40 +0,0 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#include <boost/thread/thread.hpp>
|
||||
#include <boost/thread/xtime.hpp>
|
||||
#include <iostream>
|
||||
|
||||
struct thread_alarm
|
||||
{
|
||||
thread_alarm(int secs) : m_secs(secs) { }
|
||||
void operator()()
|
||||
{
|
||||
boost::xtime xt;
|
||||
boost::xtime_get(&xt, boost::TIME_UTC);
|
||||
xt.sec += m_secs;
|
||||
|
||||
boost::thread::sleep(xt);
|
||||
|
||||
std::cout << "alarm sounded..." << std::endl;
|
||||
}
|
||||
|
||||
int m_secs;
|
||||
};
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
int secs = 5;
|
||||
std::cout << "setting alarm for 5 seconds..." << std::endl;
|
||||
thread_alarm alarm(secs);
|
||||
boost::thread thrd(alarm);
|
||||
thrd.join();
|
||||
}
|
||||
@@ -1,30 +0,0 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#include <boost/thread/thread.hpp>
|
||||
#include <iostream>
|
||||
|
||||
int count = 0;
|
||||
boost::mutex mutex;
|
||||
|
||||
void increment_count()
|
||||
{
|
||||
boost::mutex::scoped_lock lock(mutex);
|
||||
std::cout << "count = " << ++count << std::endl;
|
||||
}
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
boost::thread_group threads;
|
||||
for (int i = 0; i < 10; ++i)
|
||||
threads.create_thread(&increment_count);
|
||||
threads.join_all();
|
||||
}
|
||||
@@ -1,41 +0,0 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#include <boost/thread/thread.hpp>
|
||||
#include <boost/thread/tss.hpp>
|
||||
#include <cassert>
|
||||
|
||||
boost::thread_specific_ptr<int> value;
|
||||
|
||||
void increment()
|
||||
{
|
||||
int* p = value.get();
|
||||
++*p;
|
||||
}
|
||||
|
||||
void thread_proc()
|
||||
{
|
||||
value.reset(new int(0)); // initialize the thread's storage
|
||||
for (int i=0; i<10; ++i)
|
||||
{
|
||||
increment();
|
||||
int* p = value.get();
|
||||
assert(*p == i+1);
|
||||
}
|
||||
}
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
boost::thread_group threads;
|
||||
for (int i=0; i<5; ++i)
|
||||
threads.create_thread(&thread_proc);
|
||||
threads.join_all();
|
||||
}
|
||||
@@ -1,21 +0,0 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#include <boost/thread/thread.hpp>
|
||||
#include <boost/thread/xtime.hpp>
|
||||
|
||||
int main(int argc, char* argv[])
|
||||
{
|
||||
boost::xtime xt;
|
||||
boost::xtime_get(&xt, boost::TIME_UTC);
|
||||
xt.sec += 1;
|
||||
boost::thread::sleep(xt); // Sleep for 1 second
|
||||
}
|
||||
@@ -1,24 +0,0 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#if !defined(BOOST_THREAD_WEK01082003_HPP)
|
||||
#define BOOST_THREAD_WEK01082003_HPP
|
||||
|
||||
#include <boost/thread/thread.hpp>
|
||||
#include <boost/thread/condition.hpp>
|
||||
#include <boost/thread/exceptions.hpp>
|
||||
#include <boost/thread/mutex.hpp>
|
||||
#include <boost/thread/once.hpp>
|
||||
#include <boost/thread/recursive_mutex.hpp>
|
||||
#include <boost/thread/tss.hpp>
|
||||
#include <boost/thread/xtime.hpp>
|
||||
|
||||
#endif
|
||||
@@ -1,4 +1,4 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// Copyright (C) 2001
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
@@ -20,72 +20,23 @@
|
||||
#include <boost/thread/exceptions.hpp>
|
||||
#include <boost/utility.hpp>
|
||||
#include <boost/thread/detail/lock.hpp>
|
||||
#include <boost/thread/detail/config.hpp>
|
||||
|
||||
#if defined(BOOST_HAS_PTHREADS)
|
||||
# include <pthread.h>
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
# include "scoped_critical_region.hpp"
|
||||
#endif
|
||||
|
||||
namespace boost {
|
||||
|
||||
struct xtime;
|
||||
|
||||
namespace detail {
|
||||
|
||||
class BOOST_THREAD_DECL condition_impl : private noncopyable
|
||||
{
|
||||
friend class condition;
|
||||
|
||||
public:
|
||||
condition_impl();
|
||||
~condition_impl();
|
||||
|
||||
void notify_one();
|
||||
void notify_all();
|
||||
|
||||
#if (defined(BOOST_HAS_WINTHREADS) || defined(BOOST_HAS_MPTASKS))
|
||||
void enter_wait();
|
||||
void do_wait();
|
||||
bool do_timed_wait(const xtime& xt);
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
void do_wait(pthread_mutex_t* pmutex);
|
||||
bool do_timed_wait(const xtime& xt, pthread_mutex_t* pmutex);
|
||||
#endif
|
||||
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
void* m_gate;
|
||||
void* m_queue;
|
||||
void* m_mutex;
|
||||
unsigned m_gone; // # threads that timed out and never made it to m_queue
|
||||
unsigned long m_blocked; // # threads blocked on the condition
|
||||
unsigned m_waiting; // # threads no longer waiting for the condition but
|
||||
// still waiting to be removed from m_queue
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
pthread_cond_t m_condition;
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
MPSemaphoreID m_gate;
|
||||
MPSemaphoreID m_queue;
|
||||
threads::mac::detail::scoped_critical_region m_mutex;
|
||||
threads::mac::detail::scoped_critical_region m_mutex_mutex;
|
||||
unsigned m_gone; // # threads that timed out and never made it to m_queue
|
||||
unsigned long m_blocked; // # threads blocked on the condition
|
||||
unsigned m_waiting; // # threads no longer waiting for the condition but
|
||||
// still waiting to be removed from m_queue
|
||||
#endif
|
||||
};
|
||||
|
||||
} // namespace detail
|
||||
|
||||
class condition : private noncopyable
|
||||
{
|
||||
public:
|
||||
condition() { }
|
||||
~condition() { }
|
||||
condition();
|
||||
~condition();
|
||||
|
||||
void notify_one() { m_impl.notify_one(); }
|
||||
void notify_all() { m_impl.notify_all(); }
|
||||
void notify_one();
|
||||
void notify_all();
|
||||
|
||||
template <typename L>
|
||||
void wait(L& lock)
|
||||
@@ -131,63 +82,70 @@ public:
|
||||
}
|
||||
|
||||
private:
|
||||
detail::condition_impl m_impl;
|
||||
|
||||
template <typename M>
|
||||
void do_wait(M& mutex)
|
||||
{
|
||||
#if (defined(BOOST_HAS_WINTHREADS) || defined(BOOST_HAS_MPTASKS))
|
||||
m_impl.enter_wait();
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
enter_wait();
|
||||
#endif
|
||||
|
||||
typedef detail::thread::lock_ops<M>
|
||||
#if defined(__HP_aCC) && __HP_aCC <= 33900 && !defined(BOOST_STRICT_CONFIG)
|
||||
# define lock_ops lock_ops_ // HP confuses lock_ops witht the template
|
||||
#endif
|
||||
lock_ops;
|
||||
|
||||
typename lock_ops::lock_state state;
|
||||
typedef typename detail::thread::lock_ops<M> lock_ops;
|
||||
lock_ops::lock_state state;
|
||||
lock_ops::unlock(mutex, state);
|
||||
|
||||
#if defined(BOOST_HAS_PTHREADS)
|
||||
m_impl.do_wait(state.pmutex);
|
||||
#elif (defined(BOOST_HAS_WINTHREADS) || defined(BOOST_HAS_MPTASKS))
|
||||
m_impl.do_wait();
|
||||
do_wait(state.pmutex);
|
||||
#elif defined(BOOST_HAS_WINTHREADS)
|
||||
do_wait();
|
||||
#endif
|
||||
|
||||
lock_ops::lock(mutex, state);
|
||||
#undef lock_ops
|
||||
}
|
||||
|
||||
template <typename M>
|
||||
bool do_timed_wait(M& mutex, const xtime& xt)
|
||||
{
|
||||
#if (defined(BOOST_HAS_WINTHREADS) || defined(BOOST_HAS_MPTASKS))
|
||||
m_impl.enter_wait();
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
enter_wait();
|
||||
#endif
|
||||
|
||||
typedef detail::thread::lock_ops<M>
|
||||
#if defined(__HP_aCC) && __HP_aCC <= 33900 && !defined(BOOST_STRICT_CONFIG)
|
||||
# define lock_ops lock_ops_ // HP confuses lock_ops witht the template
|
||||
#endif
|
||||
lock_ops;
|
||||
|
||||
typename lock_ops::lock_state state;
|
||||
typedef typename detail::thread::lock_ops<M> lock_ops;
|
||||
lock_ops::lock_state state;
|
||||
lock_ops::unlock(mutex, state);
|
||||
|
||||
bool ret = false;
|
||||
|
||||
#if defined(BOOST_HAS_PTHREADS)
|
||||
ret = m_impl.do_timed_wait(xt, state.pmutex);
|
||||
#elif (defined(BOOST_HAS_WINTHREADS) || defined(BOOST_HAS_MPTASKS))
|
||||
ret = m_impl.do_timed_wait(xt);
|
||||
ret = do_timed_wait(xt, state.pmutex);
|
||||
#elif defined(BOOST_HAS_WINTHREADS)
|
||||
ret = do_timed_wait(xt);
|
||||
#endif
|
||||
|
||||
lock_ops::lock(mutex, state);
|
||||
#undef lock_ops
|
||||
|
||||
return ret;
|
||||
}
|
||||
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
void enter_wait();
|
||||
void do_wait();
|
||||
bool do_timed_wait(const xtime& xt);
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
void do_wait(pthread_mutex_t* pmutex);
|
||||
bool do_timed_wait(const xtime& xt, pthread_mutex_t* pmutex);
|
||||
#endif
|
||||
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
void* m_gate;
|
||||
void* m_queue;
|
||||
void* m_mutex;
|
||||
unsigned m_gone; // # threads that timed out and never made it to the m_queue
|
||||
unsigned long m_blocked; // # threads m_blocked m_waiting for the condition
|
||||
unsigned m_waiting; // # threads m_waiting no longer m_waiting for the condition but still
|
||||
// m_waiting to be removed from the m_queue
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
pthread_cond_t m_condition;
|
||||
#endif
|
||||
};
|
||||
|
||||
} // namespace boost
|
||||
@@ -195,8 +153,7 @@ private:
|
||||
// Change Log:
|
||||
// 8 Feb 01 WEKEMPF Initial version.
|
||||
// 22 May 01 WEKEMPF Modified to use xtime for time outs.
|
||||
// 23 May 01 WEKEMPF Removed "duration" timed_waits, as they are too
|
||||
// difficult to use with spurious wakeups.
|
||||
// 3 Jan 03 WEKEMPF Modified for DLL implementation.
|
||||
// 23 May 01 WEKEMPF Removed "duration" timed_waits, as they are too difficult
|
||||
// to use with spurious wakeups.
|
||||
|
||||
#endif // BOOST_CONDITION_WEK070601_HPP
|
||||
|
||||
100
include/boost/thread/config.hpp
Normal file
100
include/boost/thread/config.hpp
Normal file
@@ -0,0 +1,100 @@
|
||||
// Copyright (C) 2001
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
// This file is used to configure Boost.Threads during development
|
||||
// in order to decouple dependency on any Boost release. Once
|
||||
// accepted into Boost these contents will be moved to <boost/config>
|
||||
// or some other appropriate build configuration and all
|
||||
// #include <boost/thread/config.hpp> statements will be changed
|
||||
// accordingly.
|
||||
|
||||
#ifndef BOOST_THREAD_CONFIG_WEK070601_HPP
|
||||
#define BOOST_THREAD_CONFIG_WEK070601_HPP
|
||||
|
||||
#include <boost/config.hpp>
|
||||
|
||||
#error "Included <boost/thread/config.hpp>"
|
||||
|
||||
/*// Define if threading support is enabled for the toolset.
|
||||
#undef BOOST_HAS_THREADS
|
||||
|
||||
// Define if threading should be implemented in terms of Win32 threads.
|
||||
#undef BOOST_HAS_WINTHREADS
|
||||
|
||||
// Define if threading should be implemented in terms of POSIX threads.
|
||||
#undef BOOST_HAS_PTHREADS
|
||||
|
||||
// Define if BOOST_HAS_PTHREADS and pthread_delay_np() exists.
|
||||
#undef BOOST_HAS_PTHREAD_DELAY_NP
|
||||
|
||||
// Define if BOOST_HAS_PTHREADS and not BOOST_HAS_PTHREAD_DELAY_NP
|
||||
// but nanosleep can be used instead.
|
||||
#undef BOOST_HAS_NANOSLEEP
|
||||
|
||||
// Define if BOOST_HAS_PTHREADS and pthread_yield() exists.
|
||||
#undef BOOST_HAS_PTHREAD_YIELD
|
||||
|
||||
// Define if BOOST_HAS_PTHREADS and not BOOST_HAS_PTHREAD_YIELD and
|
||||
// sched_yield() exists.
|
||||
#undef BOOST_HAS_SCHED_YIELD
|
||||
|
||||
// Define if gettimeofday() exists.
|
||||
#undef BOOST_HAS_GETTIMEOFDAY
|
||||
|
||||
// Define if not BOOST_HAS_GETTIMEOFDAY and clock_gettime() exists.
|
||||
#undef BOOST_HAS_CLOCK_GETTIME
|
||||
|
||||
// Define if not BOOST_HAS_GETTIMEOFDAY and not BOOST_HAS_CLOCK_GETTIME and
|
||||
// GetSystemTimeAsFileTime() can be called with an FTIME structure.
|
||||
#undef BOOST_HAS_FTIME
|
||||
|
||||
// Define if pthread_mutexattr_settype and pthread_mutexattr_gettype exist.
|
||||
#undef BOOST_HAS_PTHREAD_MUTEXATTR_SETTYPE
|
||||
|
||||
// Here we'll set up known compiler options.
|
||||
|
||||
#if defined(BOOST_MSVC)
|
||||
# if defined(_MT)
|
||||
# define BOOST_HAS_THREADS
|
||||
# endif
|
||||
# define BOOST_HAS_WINTHREADS // comment out this to test pthreads-win32.
|
||||
# if !defined(BOOST_HAS_WINTHREADS)
|
||||
# define BOOST_HAS_PTHREADS
|
||||
# define BOOST_HAS_PTHREAD_MUTEXATTR_SETTYPE
|
||||
# define PtW32NoCatchWarn
|
||||
# pragma comment(lib, "pthreadVCE.lib")
|
||||
# endif
|
||||
# define BOOST_HAS_FTIME
|
||||
// pdm: this is for linux - is there a better #define to #if on?
|
||||
// wek: not sure how else to do this, but GNU CC on Win32 should probably
|
||||
// use BOOST_HAS_WINTHREADS, and I expect there will be other
|
||||
// platform specific variations for this compiler toolset. Need
|
||||
// to decide how to handle this.
|
||||
#elif defined( __GNUC__ )
|
||||
# define BOOST_HAS_THREADS
|
||||
# define BOOST_HAS_PTHREADS
|
||||
# define BOOST_HAS_NANOSLEEP
|
||||
# define BOOST_HAS_GETTIMEOFDAY
|
||||
// pdm: From the pthread.h header, one of these macros
|
||||
// must be defined for this stuff to exist.
|
||||
// wek: This seems like a harmless enough method to determine these
|
||||
// switches, but one should note that some implementations may not
|
||||
// use these. Notably, pthreads-win32 doesn't define either
|
||||
// __USE_UNIX98 or __USE_GNU.
|
||||
# if defined( __USE_UNIX98 )
|
||||
# define BOOST_HAS_PTHREAD_MUTEXATTR_SETTYPE
|
||||
# elif defined( __USE_GNU )
|
||||
# define BOOST_HAS_PTHREAD_MUTEXATTR_SETTYPE
|
||||
# define BOOST_HAS_PTHREAD_YIELD
|
||||
# endif
|
||||
#endif*/
|
||||
|
||||
#endif // BOOST_THREAD_CONFIG_WEK070601_HPP
|
||||
@@ -1,25 +0,0 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#ifndef BOOST_THREAD_CONFIG_WEK01032003_HPP
|
||||
#define BOOST_THREAD_CONFIG_WEK01032003_HPP
|
||||
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
# if defined(BOOST_THREAD_BUILD_DLL)
|
||||
# define BOOST_THREAD_DECL __declspec(dllexport)
|
||||
# else
|
||||
# define BOOST_THREAD_DECL __declspec(dllimport)
|
||||
# endif
|
||||
#else
|
||||
# define BOOST_THREAD_DECL
|
||||
#endif // BOOST_THREAD_SHARED_LIB
|
||||
|
||||
#endif // BOOST_THREAD_CONFIG_WEK1032003_HPP
|
||||
@@ -1,44 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_FORCE_CAST_MJM012402_HPP
|
||||
#define BOOST_FORCE_CAST_MJM012402_HPP
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace detail {
|
||||
|
||||
namespace thread {
|
||||
|
||||
|
||||
// force_cast will convert anything to anything.
|
||||
|
||||
// general case
|
||||
template<class Return_Type, class Argument_Type>
|
||||
inline Return_Type &force_cast(Argument_Type &rSrc)
|
||||
{ return(*reinterpret_cast<Return_Type *>(&rSrc)); }
|
||||
|
||||
// specialization for const
|
||||
template<class Return_Type, class Argument_Type>
|
||||
inline const Return_Type &force_cast(const Argument_Type &rSrc)
|
||||
{ return(*reinterpret_cast<const Return_Type *>(&rSrc)); }
|
||||
|
||||
|
||||
} // namespace thread
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_FORCE_CAST_MJM012402_HPP
|
||||
@@ -20,182 +20,182 @@ namespace boost {
|
||||
class condition;
|
||||
struct xtime;
|
||||
|
||||
namespace detail { namespace thread {
|
||||
namespace detail { namespace thread {
|
||||
|
||||
template <typename Mutex>
|
||||
class lock_ops : private noncopyable
|
||||
{
|
||||
private:
|
||||
lock_ops() { }
|
||||
template <typename Mutex>
|
||||
class lock_ops : private noncopyable
|
||||
{
|
||||
private:
|
||||
lock_ops() { }
|
||||
|
||||
public:
|
||||
typedef typename Mutex::cv_state lock_state;
|
||||
public:
|
||||
typedef typename Mutex::cv_state lock_state;
|
||||
|
||||
static void lock(Mutex& m)
|
||||
{
|
||||
m.do_lock();
|
||||
}
|
||||
static bool trylock(Mutex& m)
|
||||
{
|
||||
return m.do_trylock();
|
||||
}
|
||||
static bool timedlock(Mutex& m, const xtime& xt)
|
||||
{
|
||||
return m.do_timedlock(xt);
|
||||
}
|
||||
static void unlock(Mutex& m)
|
||||
{
|
||||
m.do_unlock();
|
||||
}
|
||||
static void lock(Mutex& m, lock_state& state)
|
||||
{
|
||||
m.do_lock(state);
|
||||
}
|
||||
static void unlock(Mutex& m, lock_state& state)
|
||||
{
|
||||
m.do_unlock(state);
|
||||
}
|
||||
};
|
||||
static void lock(Mutex& m)
|
||||
{
|
||||
m.do_lock();
|
||||
}
|
||||
static bool trylock(Mutex& m)
|
||||
{
|
||||
return m.do_trylock();
|
||||
}
|
||||
static bool timedlock(Mutex& m, const xtime& xt)
|
||||
{
|
||||
return m.do_timedlock(xt);
|
||||
}
|
||||
static void unlock(Mutex& m)
|
||||
{
|
||||
m.do_unlock();
|
||||
}
|
||||
static void lock(Mutex& m, lock_state& state)
|
||||
{
|
||||
m.do_lock(state);
|
||||
}
|
||||
static void unlock(Mutex& m, lock_state& state)
|
||||
{
|
||||
m.do_unlock(state);
|
||||
}
|
||||
};
|
||||
|
||||
template <typename Mutex>
|
||||
class scoped_lock : private noncopyable
|
||||
{
|
||||
public:
|
||||
typedef Mutex mutex_type;
|
||||
|
||||
explicit scoped_lock(Mutex& mx, bool initially_locked=true)
|
||||
: m_mutex(mx), m_locked(false)
|
||||
template <typename Mutex>
|
||||
class scoped_lock : private noncopyable
|
||||
{
|
||||
if (initially_locked) lock();
|
||||
}
|
||||
~scoped_lock()
|
||||
public:
|
||||
typedef Mutex mutex_type;
|
||||
|
||||
explicit scoped_lock(Mutex& mx, bool initially_locked=true)
|
||||
: m_mutex(mx), m_locked(false)
|
||||
{
|
||||
if (initially_locked) lock();
|
||||
}
|
||||
~scoped_lock()
|
||||
{
|
||||
if (m_locked) unlock();
|
||||
}
|
||||
|
||||
void lock()
|
||||
{
|
||||
if (m_locked) throw lock_error();
|
||||
lock_ops<Mutex>::lock(m_mutex);
|
||||
m_locked = true;
|
||||
}
|
||||
void unlock()
|
||||
{
|
||||
if (!m_locked) throw lock_error();
|
||||
lock_ops<Mutex>::unlock(m_mutex);
|
||||
m_locked = false;
|
||||
}
|
||||
|
||||
bool locked() const { return m_locked; }
|
||||
operator const void*() const { return m_locked ? this : 0; }
|
||||
|
||||
private:
|
||||
friend class boost::condition;
|
||||
|
||||
Mutex& m_mutex;
|
||||
bool m_locked;
|
||||
};
|
||||
|
||||
template <typename TryMutex>
|
||||
class scoped_try_lock : private noncopyable
|
||||
{
|
||||
if (m_locked) unlock();
|
||||
}
|
||||
public:
|
||||
typedef TryMutex mutex_type;
|
||||
|
||||
void lock()
|
||||
explicit scoped_try_lock(TryMutex& mx)
|
||||
: m_mutex(mx), m_locked(false)
|
||||
{
|
||||
try_lock();
|
||||
}
|
||||
scoped_try_lock(TryMutex& mx, bool initially_locked)
|
||||
: m_mutex(mx), m_locked(false)
|
||||
{
|
||||
if (initially_locked) lock();
|
||||
}
|
||||
~scoped_try_lock()
|
||||
{
|
||||
if (m_locked) unlock();
|
||||
}
|
||||
|
||||
void lock()
|
||||
{
|
||||
if (m_locked) throw lock_error();
|
||||
lock_ops<TryMutex>::lock(m_mutex);
|
||||
m_locked = true;
|
||||
}
|
||||
bool try_lock()
|
||||
{
|
||||
if (m_locked) throw lock_error();
|
||||
return (m_locked = lock_ops<TryMutex>::trylock(m_mutex));
|
||||
}
|
||||
void unlock()
|
||||
{
|
||||
if (!m_locked) throw lock_error();
|
||||
lock_ops<TryMutex>::unlock(m_mutex);
|
||||
m_locked = false;
|
||||
}
|
||||
|
||||
bool locked() const { return m_locked; }
|
||||
operator const void*() const { return m_locked ? this : 0; }
|
||||
|
||||
private:
|
||||
friend class boost::condition;
|
||||
|
||||
TryMutex& m_mutex;
|
||||
bool m_locked;
|
||||
};
|
||||
|
||||
template <typename TimedMutex>
|
||||
class scoped_timed_lock : private noncopyable
|
||||
{
|
||||
if (m_locked) throw lock_error();
|
||||
lock_ops<Mutex>::lock(m_mutex);
|
||||
m_locked = true;
|
||||
}
|
||||
void unlock()
|
||||
{
|
||||
if (!m_locked) throw lock_error();
|
||||
lock_ops<Mutex>::unlock(m_mutex);
|
||||
m_locked = false;
|
||||
}
|
||||
public:
|
||||
typedef TimedMutex mutex_type;
|
||||
|
||||
bool locked() const { return m_locked; }
|
||||
operator const void*() const { return m_locked ? this : 0; }
|
||||
scoped_timed_lock(TimedMutex& mx, const xtime& xt)
|
||||
: m_mutex(mx), m_locked(false)
|
||||
{
|
||||
timed_lock(xt);
|
||||
}
|
||||
scoped_timed_lock(TimedMutex& mx, bool initially_locked)
|
||||
: m_mutex(mx), m_locked(false)
|
||||
{
|
||||
if (initially_locked) lock();
|
||||
}
|
||||
~scoped_timed_lock()
|
||||
{
|
||||
if (m_locked) unlock();
|
||||
}
|
||||
|
||||
private:
|
||||
friend class boost::condition;
|
||||
void lock()
|
||||
{
|
||||
if (m_locked) throw lock_error();
|
||||
lock_ops<TimedMutex>::lock(m_mutex);
|
||||
m_locked = true;
|
||||
}
|
||||
bool timed_lock(const xtime& xt)
|
||||
{
|
||||
if (m_locked) throw lock_error();
|
||||
return (m_locked = lock_ops<TimedMutex>::timedlock(m_mutex, xt));
|
||||
}
|
||||
void unlock()
|
||||
{
|
||||
if (!m_locked) throw lock_error();
|
||||
lock_ops<TimedMutex>::unlock(m_mutex);
|
||||
m_locked = false;
|
||||
}
|
||||
|
||||
Mutex& m_mutex;
|
||||
bool m_locked;
|
||||
};
|
||||
bool locked() const { return m_locked; }
|
||||
operator const void*() const { return m_locked ? this : 0; }
|
||||
|
||||
template <typename TryMutex>
|
||||
class scoped_try_lock : private noncopyable
|
||||
{
|
||||
public:
|
||||
typedef TryMutex mutex_type;
|
||||
private:
|
||||
friend class boost::condition;
|
||||
|
||||
explicit scoped_try_lock(TryMutex& mx)
|
||||
: m_mutex(mx), m_locked(false)
|
||||
{
|
||||
try_lock();
|
||||
}
|
||||
scoped_try_lock(TryMutex& mx, bool initially_locked)
|
||||
: m_mutex(mx), m_locked(false)
|
||||
{
|
||||
if (initially_locked) lock();
|
||||
}
|
||||
~scoped_try_lock()
|
||||
{
|
||||
if (m_locked) unlock();
|
||||
}
|
||||
TimedMutex& m_mutex;
|
||||
bool m_locked;
|
||||
};
|
||||
|
||||
void lock()
|
||||
{
|
||||
if (m_locked) throw lock_error();
|
||||
lock_ops<TryMutex>::lock(m_mutex);
|
||||
m_locked = true;
|
||||
}
|
||||
bool try_lock()
|
||||
{
|
||||
if (m_locked) throw lock_error();
|
||||
return (m_locked = lock_ops<TryMutex>::trylock(m_mutex));
|
||||
}
|
||||
void unlock()
|
||||
{
|
||||
if (!m_locked) throw lock_error();
|
||||
lock_ops<TryMutex>::unlock(m_mutex);
|
||||
m_locked = false;
|
||||
}
|
||||
|
||||
bool locked() const { return m_locked; }
|
||||
operator const void*() const { return m_locked ? this : 0; }
|
||||
|
||||
private:
|
||||
friend class boost::condition;
|
||||
|
||||
TryMutex& m_mutex;
|
||||
bool m_locked;
|
||||
};
|
||||
|
||||
template <typename TimedMutex>
|
||||
class scoped_timed_lock : private noncopyable
|
||||
{
|
||||
public:
|
||||
typedef TimedMutex mutex_type;
|
||||
|
||||
scoped_timed_lock(TimedMutex& mx, const xtime& xt)
|
||||
: m_mutex(mx), m_locked(false)
|
||||
{
|
||||
timed_lock(xt);
|
||||
}
|
||||
scoped_timed_lock(TimedMutex& mx, bool initially_locked)
|
||||
: m_mutex(mx), m_locked(false)
|
||||
{
|
||||
if (initially_locked) lock();
|
||||
}
|
||||
~scoped_timed_lock()
|
||||
{
|
||||
if (m_locked) unlock();
|
||||
}
|
||||
|
||||
void lock()
|
||||
{
|
||||
if (m_locked) throw lock_error();
|
||||
lock_ops<TimedMutex>::lock(m_mutex);
|
||||
m_locked = true;
|
||||
}
|
||||
bool timed_lock(const xtime& xt)
|
||||
{
|
||||
if (m_locked) throw lock_error();
|
||||
return (m_locked = lock_ops<TimedMutex>::timedlock(m_mutex, xt));
|
||||
}
|
||||
void unlock()
|
||||
{
|
||||
if (!m_locked) throw lock_error();
|
||||
lock_ops<TimedMutex>::unlock(m_mutex);
|
||||
m_locked = false;
|
||||
}
|
||||
|
||||
bool locked() const { return m_locked; }
|
||||
operator const void*() const { return m_locked ? this : 0; }
|
||||
|
||||
private:
|
||||
friend class boost::condition;
|
||||
|
||||
TimedMutex& m_mutex;
|
||||
bool m_locked;
|
||||
};
|
||||
|
||||
} // namespace thread
|
||||
} // namespace detail
|
||||
} // namespace thread
|
||||
} // namespace detail
|
||||
} // namespace boost
|
||||
|
||||
// Change Log:
|
||||
|
||||
@@ -1,64 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_SINGLETON_MJM012402_HPP
|
||||
#define BOOST_SINGLETON_MJM012402_HPP
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace detail {
|
||||
|
||||
namespace thread {
|
||||
|
||||
// class singleton has the same goal as all singletons: create one instance of a
|
||||
// class on demand, then dish it out as requested.
|
||||
|
||||
template<class T>
|
||||
class singleton: private T
|
||||
{
|
||||
private:
|
||||
singleton();
|
||||
~singleton();
|
||||
|
||||
public:
|
||||
static T &instance();
|
||||
};
|
||||
|
||||
|
||||
template<class T>
|
||||
inline singleton<T>::singleton()
|
||||
{ /* no-op */ }
|
||||
|
||||
template<class T>
|
||||
inline singleton<T>::~singleton()
|
||||
{ /* no-op */ }
|
||||
|
||||
|
||||
template<class T>
|
||||
/*static*/ T &singleton<T>::instance()
|
||||
{
|
||||
// function-local static to force this to work correctly at static
|
||||
// initialization time.
|
||||
static singleton<T> s_oT;
|
||||
return(s_oT);
|
||||
}
|
||||
|
||||
|
||||
} // namespace thread
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_SINGLETON_MJM012402_HPP
|
||||
@@ -1,25 +0,0 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. William E. Kempf makes no representations
|
||||
// about the suitability of this software for any purpose.
|
||||
// It is provided "as is" without express or implied warranty.
|
||||
|
||||
#include <boost/config.hpp>
|
||||
#ifndef BOOST_HAS_THREADS
|
||||
# error Thread support is unavailable!
|
||||
#endif
|
||||
|
||||
#include <boost/thread/detail/config.hpp>
|
||||
|
||||
#ifdef BOOST_HAS_WINTHREADS
|
||||
|
||||
#include <boost/thread/detail/config.hpp>
|
||||
|
||||
extern "C" BOOST_THREAD_DECL int on_thread_exit(void (__cdecl * func)(void));
|
||||
|
||||
#endif // BOOST_HAS_WINTHREADS
|
||||
@@ -1,4 +1,4 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// Copyright (C) 2001
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
@@ -12,9 +12,6 @@
|
||||
#ifndef BOOST_THREAD_EXCEPTIONS_PDM070801_H
|
||||
#define BOOST_THREAD_EXCEPTIONS_PDM070801_H
|
||||
|
||||
#include <boost/config.hpp>
|
||||
#include <boost/thread/detail/config.hpp>
|
||||
|
||||
// pdm: Sorry, but this class is used all over the place & I end up
|
||||
// with recursive headers if I don't separate it
|
||||
// wek: Not sure why recursive headers would cause compilation problems
|
||||
@@ -25,13 +22,13 @@
|
||||
|
||||
namespace boost {
|
||||
|
||||
class BOOST_THREAD_DECL lock_error : public std::logic_error
|
||||
class lock_error : public std::runtime_error
|
||||
{
|
||||
public:
|
||||
lock_error();
|
||||
};
|
||||
|
||||
class BOOST_THREAD_DECL thread_resource_error : public std::runtime_error
|
||||
class thread_resource_error : public std::runtime_error
|
||||
{
|
||||
public:
|
||||
thread_resource_error();
|
||||
@@ -39,7 +36,4 @@ public:
|
||||
|
||||
} // namespace boost
|
||||
|
||||
// Change log:
|
||||
// 3 Jan 03 WEKEMPF Modified for DLL implementation.
|
||||
|
||||
#endif // BOOST_THREAD_CONFIG_PDM070801_H
|
||||
|
||||
@@ -1,4 +1,4 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// Copyright (C) 2001
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
@@ -19,21 +19,16 @@
|
||||
|
||||
#include <boost/utility.hpp>
|
||||
#include <boost/thread/detail/lock.hpp>
|
||||
#include <boost/thread/detail/config.hpp>
|
||||
|
||||
#if defined(BOOST_HAS_PTHREADS)
|
||||
# include <pthread.h>
|
||||
#endif
|
||||
|
||||
#if defined(BOOST_HAS_MPTASKS)
|
||||
# include "scoped_critical_region.hpp"
|
||||
#endif
|
||||
|
||||
namespace boost {
|
||||
|
||||
struct xtime;
|
||||
|
||||
class BOOST_THREAD_DECL mutex : private noncopyable
|
||||
class mutex : private noncopyable
|
||||
{
|
||||
public:
|
||||
friend class detail::thread::lock_ops<mutex>;
|
||||
@@ -51,10 +46,6 @@ private:
|
||||
{
|
||||
pthread_mutex_t* pmutex;
|
||||
};
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
struct cv_state
|
||||
{
|
||||
};
|
||||
#endif
|
||||
void do_lock();
|
||||
void do_unlock();
|
||||
@@ -65,13 +56,10 @@ private:
|
||||
void* m_mutex;
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
pthread_mutex_t m_mutex;
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
threads::mac::detail::scoped_critical_region m_mutex;
|
||||
threads::mac::detail::scoped_critical_region m_mutex_mutex;
|
||||
#endif
|
||||
};
|
||||
|
||||
class BOOST_THREAD_DECL try_mutex : private noncopyable
|
||||
class try_mutex : private noncopyable
|
||||
{
|
||||
public:
|
||||
friend class detail::thread::lock_ops<try_mutex>;
|
||||
@@ -90,10 +78,6 @@ private:
|
||||
{
|
||||
pthread_mutex_t* pmutex;
|
||||
};
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
struct cv_state
|
||||
{
|
||||
};
|
||||
#endif
|
||||
void do_lock();
|
||||
bool do_trylock();
|
||||
@@ -105,13 +89,10 @@ private:
|
||||
void* m_mutex;
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
pthread_mutex_t m_mutex;
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
threads::mac::detail::scoped_critical_region m_mutex;
|
||||
threads::mac::detail::scoped_critical_region m_mutex_mutex;
|
||||
#endif
|
||||
};
|
||||
|
||||
class BOOST_THREAD_DECL timed_mutex : private noncopyable
|
||||
class timed_mutex : private noncopyable
|
||||
{
|
||||
public:
|
||||
friend class detail::thread::lock_ops<timed_mutex>;
|
||||
@@ -131,10 +112,6 @@ private:
|
||||
{
|
||||
pthread_mutex_t* pmutex;
|
||||
};
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
struct cv_state
|
||||
{
|
||||
};
|
||||
#endif
|
||||
void do_lock();
|
||||
bool do_trylock();
|
||||
@@ -149,9 +126,6 @@ private:
|
||||
pthread_mutex_t m_mutex;
|
||||
pthread_cond_t m_condition;
|
||||
bool m_locked;
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
threads::mac::detail::scoped_critical_region m_mutex;
|
||||
threads::mac::detail::scoped_critical_region m_mutex_mutex;
|
||||
#endif
|
||||
};
|
||||
|
||||
@@ -161,6 +135,5 @@ private:
|
||||
// 8 Feb 01 WEKEMPF Initial version.
|
||||
// 22 May 01 WEKEMPF Modified to use xtime for time outs. Factored out
|
||||
// to three classes, mutex, try_mutex and timed_mutex.
|
||||
// 3 Jan 03 WEKEMPF Modified for DLL implementation.
|
||||
|
||||
#endif // BOOST_MUTEX_WEK070601_HPP
|
||||
|
||||
@@ -1,4 +1,4 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// Copyright (C) 2001
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
@@ -17,8 +17,6 @@
|
||||
# error Thread support is unavailable!
|
||||
#endif
|
||||
|
||||
#include <boost/thread/detail/config.hpp>
|
||||
|
||||
#if defined(BOOST_HAS_PTHREADS)
|
||||
# include <pthread.h>
|
||||
#endif
|
||||
@@ -30,14 +28,14 @@ namespace boost {
|
||||
typedef pthread_once_t once_flag;
|
||||
#define BOOST_ONCE_INIT PTHREAD_ONCE_INIT
|
||||
|
||||
#elif (defined(BOOST_HAS_WINTHREADS) || defined(BOOST_HAS_MPTASKS))
|
||||
#elif defined(BOOST_HAS_WINTHREADS)
|
||||
|
||||
typedef long once_flag;
|
||||
#define BOOST_ONCE_INIT 0
|
||||
typedef bool once_flag;
|
||||
#define BOOST_ONCE_INIT false
|
||||
|
||||
#endif
|
||||
|
||||
void BOOST_THREAD_DECL call_once(void (*func)(), once_flag& flag);
|
||||
void call_once(void (*func)(), once_flag& flag);
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
@@ -1,4 +1,4 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// Copyright (C) 2001
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
@@ -19,19 +19,16 @@
|
||||
|
||||
#include <boost/utility.hpp>
|
||||
#include <boost/thread/detail/lock.hpp>
|
||||
#include <boost/thread/detail/config.hpp>
|
||||
|
||||
#if defined(BOOST_HAS_PTHREADS)
|
||||
# include <pthread.h>
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
# include "scoped_critical_region.hpp"
|
||||
#endif
|
||||
|
||||
namespace boost {
|
||||
|
||||
struct xtime;
|
||||
|
||||
class BOOST_THREAD_DECL recursive_mutex : private noncopyable
|
||||
class recursive_mutex : private noncopyable
|
||||
{
|
||||
public:
|
||||
friend class detail::thread::lock_ops<recursive_mutex>;
|
||||
@@ -42,7 +39,7 @@ public:
|
||||
~recursive_mutex();
|
||||
|
||||
private:
|
||||
#if (defined(BOOST_HAS_WINTHREADS) || defined(BOOST_HAS_MPTASKS))
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
typedef std::size_t cv_state;
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
struct cv_state
|
||||
@@ -67,27 +64,22 @@ private:
|
||||
pthread_t m_thread_id;
|
||||
bool m_valid_id;
|
||||
# endif
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
threads::mac::detail::scoped_critical_region m_mutex;
|
||||
threads::mac::detail::scoped_critical_region m_mutex_mutex;
|
||||
std::size_t m_count;
|
||||
#endif
|
||||
};
|
||||
|
||||
class BOOST_THREAD_DECL recursive_try_mutex : private noncopyable
|
||||
class recursive_try_mutex : private noncopyable
|
||||
{
|
||||
public:
|
||||
friend class detail::thread::lock_ops<recursive_try_mutex>;
|
||||
|
||||
typedef detail::thread::scoped_lock<recursive_try_mutex> scoped_lock;
|
||||
typedef detail::thread::scoped_try_lock<
|
||||
recursive_try_mutex> scoped_try_lock;
|
||||
typedef detail::thread::scoped_try_lock<recursive_try_mutex> scoped_try_lock;
|
||||
|
||||
recursive_try_mutex();
|
||||
~recursive_try_mutex();
|
||||
|
||||
private:
|
||||
#if (defined(BOOST_HAS_WINTHREADS) || defined(BOOST_HAS_MPTASKS))
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
typedef std::size_t cv_state;
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
struct cv_state
|
||||
@@ -113,29 +105,23 @@ private:
|
||||
pthread_t m_thread_id;
|
||||
bool m_valid_id;
|
||||
# endif
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
threads::mac::detail::scoped_critical_region m_mutex;
|
||||
threads::mac::detail::scoped_critical_region m_mutex_mutex;
|
||||
std::size_t m_count;
|
||||
#endif
|
||||
};
|
||||
|
||||
class BOOST_THREAD_DECL recursive_timed_mutex : private noncopyable
|
||||
class recursive_timed_mutex : private noncopyable
|
||||
{
|
||||
public:
|
||||
friend class detail::thread::lock_ops<recursive_timed_mutex>;
|
||||
|
||||
typedef detail::thread::scoped_lock<recursive_timed_mutex> scoped_lock;
|
||||
typedef detail::thread::scoped_try_lock<
|
||||
recursive_timed_mutex> scoped_try_lock;
|
||||
typedef detail::thread::scoped_timed_lock<
|
||||
recursive_timed_mutex> scoped_timed_lock;
|
||||
typedef detail::thread::scoped_try_lock<recursive_timed_mutex> scoped_try_lock;
|
||||
typedef detail::thread::scoped_timed_lock<recursive_timed_mutex> scoped_timed_lock;
|
||||
|
||||
recursive_timed_mutex();
|
||||
~recursive_timed_mutex();
|
||||
|
||||
private:
|
||||
#if (defined(BOOST_HAS_WINTHREADS) || defined(BOOST_HAS_MPTASKS))
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
typedef std::size_t cv_state;
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
struct cv_state
|
||||
@@ -160,10 +146,6 @@ private:
|
||||
pthread_t m_thread_id;
|
||||
bool m_valid_id;
|
||||
unsigned m_count;
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
threads::mac::detail::scoped_critical_region m_mutex;
|
||||
threads::mac::detail::scoped_critical_region m_mutex_mutex;
|
||||
std::size_t m_count;
|
||||
#endif
|
||||
};
|
||||
|
||||
@@ -174,7 +156,5 @@ private:
|
||||
// 1 Jun 01 WEKEMPF Modified to use xtime for time outs. Factored out
|
||||
// to three classes, mutex, try_mutex and timed_mutex.
|
||||
// 11 Jun 01 WEKEMPF Modified to use PTHREAD_MUTEX_RECURSIVE if available.
|
||||
// 3 Jan 03 WEKEMPF Modified for DLL implementation.
|
||||
|
||||
|
||||
#endif // BOOST_RECURSIVE_MUTEX_WEK070601_HPP
|
||||
|
||||
@@ -1,4 +1,4 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// Copyright (C) 2001
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
@@ -20,22 +20,19 @@
|
||||
#include <boost/utility.hpp>
|
||||
#include <boost/function.hpp>
|
||||
#include <boost/thread/mutex.hpp>
|
||||
#include <boost/thread/detail/config.hpp>
|
||||
#include <list>
|
||||
#include <memory>
|
||||
|
||||
#if defined(BOOST_HAS_PTHREADS)
|
||||
# include <pthread.h>
|
||||
# include <boost/thread/condition.hpp>
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
# include <Multiprocessing.h>
|
||||
#endif
|
||||
|
||||
namespace boost {
|
||||
|
||||
struct xtime;
|
||||
|
||||
class BOOST_THREAD_DECL thread : private noncopyable
|
||||
class thread : private noncopyable
|
||||
{
|
||||
public:
|
||||
thread();
|
||||
@@ -57,14 +54,11 @@ private:
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
private:
|
||||
pthread_t m_thread;
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
MPQueueID m_pJoinQueueID;
|
||||
MPTaskID m_pTaskID;
|
||||
#endif
|
||||
bool m_joinable;
|
||||
};
|
||||
|
||||
class BOOST_THREAD_DECL thread_group : private noncopyable
|
||||
class thread_group : private noncopyable
|
||||
{
|
||||
public:
|
||||
thread_group();
|
||||
|
||||
@@ -1,4 +1,4 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// Copyright (C) 2001
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
@@ -18,42 +18,32 @@
|
||||
#endif
|
||||
|
||||
#include <boost/utility.hpp>
|
||||
#include <boost/thread/detail/config.hpp>
|
||||
|
||||
#if defined(BOOST_HAS_PTHREADS)
|
||||
# include <pthread.h>
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
# include <Multiprocessing.h>
|
||||
#endif
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace detail {
|
||||
class BOOST_THREAD_DECL tss : private noncopyable
|
||||
{
|
||||
public:
|
||||
tss(void (*cleanup)(void*)=0);
|
||||
~tss();
|
||||
namespace detail {
|
||||
class tss : private noncopyable
|
||||
{
|
||||
public:
|
||||
tss(void (*cleanup)(void*)=0);
|
||||
~tss();
|
||||
|
||||
void* get() const;
|
||||
bool set(void* value);
|
||||
void* get() const;
|
||||
bool set(void* value);
|
||||
|
||||
private:
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
unsigned long m_key;
|
||||
void (*m_cleanup)(void*);
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
pthread_key_t m_key;
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
TaskStorageIndex m_key;
|
||||
void (*m_cleanup)(void*);
|
||||
#endif
|
||||
};
|
||||
|
||||
#if defined(BOOST_HAS_MPTASKS)
|
||||
void thread_cleanup();
|
||||
#endif
|
||||
}
|
||||
private:
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
unsigned long m_key;
|
||||
void (*m_cleanup)(void*);
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
pthread_key_t m_key;
|
||||
#endif
|
||||
};
|
||||
}
|
||||
|
||||
template <typename T>
|
||||
class thread_specific_ptr : private noncopyable
|
||||
@@ -65,13 +55,7 @@ public:
|
||||
T* operator->() const { return get(); }
|
||||
T& operator*() const { return *get(); }
|
||||
T* release() { T* temp = get(); m_tss.set(0); return temp; }
|
||||
void reset(T* p=0)
|
||||
{
|
||||
T* cur = get();
|
||||
if (cur == p) return;
|
||||
delete cur;
|
||||
m_tss.set(p);
|
||||
}
|
||||
void reset(T* p=0) { T* cur = get(); if (cur == p) return; delete cur; m_tss.set(p); }
|
||||
|
||||
private:
|
||||
static void cleanup(void* p) { delete static_cast<T*>(p); }
|
||||
|
||||
@@ -1,4 +1,4 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// Copyright (C) 2001
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
@@ -12,9 +12,8 @@
|
||||
#ifndef BOOST_XTIME_WEK070601_HPP
|
||||
#define BOOST_XTIME_WEK070601_HPP
|
||||
|
||||
#include <boost/config.hpp>
|
||||
#include <boost/cstdint.hpp>
|
||||
#include <boost/thread/detail/config.hpp>
|
||||
#include <boost/config.hpp>
|
||||
|
||||
namespace boost {
|
||||
|
||||
@@ -40,14 +39,7 @@ struct xtime
|
||||
int_fast32_t nsec;
|
||||
};
|
||||
|
||||
int BOOST_THREAD_DECL xtime_get(struct xtime* xtp, int clock_type);
|
||||
inline int xtime_cmp(const xtime& xt1, const xtime& xt2)
|
||||
{
|
||||
int res = (int)(xt1.sec - xt2.sec);
|
||||
if (res == 0)
|
||||
res = (int)(xt1.nsec - xt2.nsec);
|
||||
return res;
|
||||
}
|
||||
int xtime_get(struct xtime* xtp, int clock_type);
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
@@ -1,8 +0,0 @@
|
||||
<html>
|
||||
<head>
|
||||
<meta http-equiv="refresh" content="0; URL=doc/index.html">
|
||||
</head>
|
||||
<body>
|
||||
Automatic redirection failed, please go to <a href="doc/index.html">doc/index.html</a>
|
||||
</body>
|
||||
</html>
|
||||
@@ -1,4 +1,4 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// Copyright (C) 2001
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
@@ -18,56 +18,46 @@
|
||||
#include "timeconv.inl"
|
||||
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
# ifndef NOMINMAX
|
||||
# define NOMINMAX
|
||||
# endif
|
||||
# define NOMINMAX
|
||||
# include <windows.h>
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
# include <errno.h>
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
# include <MacErrors.h>
|
||||
# include "mac/init.hpp"
|
||||
# include "mac/safe.hpp"
|
||||
#endif
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace detail {
|
||||
|
||||
#if defined(BOOST_HAS_WINTHREADS)
|
||||
condition_impl::condition_impl()
|
||||
condition::condition()
|
||||
: m_gone(0), m_blocked(0), m_waiting(0)
|
||||
{
|
||||
m_gate = reinterpret_cast<void*>(CreateSemaphore(0, 1, 1, 0));
|
||||
m_queue = reinterpret_cast<void*>(CreateSemaphore(0, 0,
|
||||
std::numeric_limits<long>::max(),
|
||||
0));
|
||||
m_queue = reinterpret_cast<void*>(CreateSemaphore(0, 0, std::numeric_limits<long>::max(), 0));
|
||||
m_mutex = reinterpret_cast<void*>(CreateMutex(0, 0, 0));
|
||||
|
||||
if (!m_gate || !m_queue || !m_mutex)
|
||||
{
|
||||
int res = 0;
|
||||
if (m_gate)
|
||||
{
|
||||
int res = 0;
|
||||
if (m_gate)
|
||||
{
|
||||
res = CloseHandle(reinterpret_cast<HANDLE>(m_gate));
|
||||
assert(res);
|
||||
}
|
||||
if (m_queue)
|
||||
{
|
||||
res = CloseHandle(reinterpret_cast<HANDLE>(m_queue));
|
||||
assert(res);
|
||||
}
|
||||
if (m_mutex)
|
||||
{
|
||||
res = CloseHandle(reinterpret_cast<HANDLE>(m_mutex));
|
||||
assert(res);
|
||||
}
|
||||
|
||||
throw thread_resource_error();
|
||||
res = CloseHandle(reinterpret_cast<HANDLE>(m_gate));
|
||||
assert(res);
|
||||
}
|
||||
if (m_queue)
|
||||
{
|
||||
res = CloseHandle(reinterpret_cast<HANDLE>(m_queue));
|
||||
assert(res);
|
||||
}
|
||||
if (m_mutex)
|
||||
{
|
||||
res = CloseHandle(reinterpret_cast<HANDLE>(m_mutex));
|
||||
assert(res);
|
||||
}
|
||||
|
||||
throw thread_resource_error();
|
||||
}
|
||||
}
|
||||
|
||||
condition_impl::~condition_impl()
|
||||
condition::~condition()
|
||||
{
|
||||
int res = 0;
|
||||
res = CloseHandle(reinterpret_cast<HANDLE>(m_gate));
|
||||
@@ -78,7 +68,7 @@ condition_impl::~condition_impl()
|
||||
assert(res);
|
||||
}
|
||||
|
||||
void condition_impl::notify_one()
|
||||
void condition::notify_one()
|
||||
{
|
||||
unsigned signals = 0;
|
||||
|
||||
@@ -87,50 +77,49 @@ void condition_impl::notify_one()
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
|
||||
if (m_waiting != 0) // the m_gate is already closed
|
||||
{
|
||||
if (m_blocked == 0)
|
||||
{
|
||||
if (m_blocked == 0)
|
||||
{
|
||||
res = ReleaseMutex(reinterpret_cast<HANDLE>(m_mutex));
|
||||
assert(res);
|
||||
return;
|
||||
}
|
||||
|
||||
++m_waiting;
|
||||
--m_blocked;
|
||||
signals = 1;
|
||||
res = ReleaseMutex(reinterpret_cast<HANDLE>(m_mutex));
|
||||
assert(res);
|
||||
return;
|
||||
}
|
||||
|
||||
++m_waiting;
|
||||
--m_blocked;
|
||||
}
|
||||
else
|
||||
{
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_gate), INFINITE);
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
if (m_blocked > m_gone)
|
||||
{
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_gate), INFINITE);
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
if (m_blocked > m_gone)
|
||||
{
|
||||
if (m_gone != 0)
|
||||
{
|
||||
m_blocked -= m_gone;
|
||||
m_gone = 0;
|
||||
}
|
||||
signals = m_waiting = 1;
|
||||
--m_blocked;
|
||||
}
|
||||
else
|
||||
{
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0);
|
||||
assert(res);
|
||||
}
|
||||
if (m_gone != 0)
|
||||
{
|
||||
m_blocked -= m_gone;
|
||||
m_gone = 0;
|
||||
}
|
||||
signals = m_waiting = 1;
|
||||
--m_blocked;
|
||||
}
|
||||
else
|
||||
{
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0);
|
||||
assert(res);
|
||||
}
|
||||
|
||||
res = ReleaseMutex(reinterpret_cast<HANDLE>(m_mutex));
|
||||
assert(res);
|
||||
res = ReleaseMutex(reinterpret_cast<HANDLE>(m_mutex));
|
||||
assert(res);
|
||||
|
||||
if (signals)
|
||||
if (signals)
|
||||
{
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_queue), signals, 0);
|
||||
assert(res);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
void condition_impl::notify_all()
|
||||
void condition::notify_all()
|
||||
{
|
||||
unsigned signals = 0;
|
||||
|
||||
@@ -139,50 +128,49 @@ void condition_impl::notify_all()
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
|
||||
if (m_waiting != 0) // the m_gate is already closed
|
||||
{
|
||||
if (m_blocked == 0)
|
||||
{
|
||||
if (m_blocked == 0)
|
||||
{
|
||||
res = ReleaseMutex(reinterpret_cast<HANDLE>(m_mutex));
|
||||
assert(res);
|
||||
return;
|
||||
}
|
||||
res = ReleaseMutex(reinterpret_cast<HANDLE>(m_mutex));
|
||||
assert(res);
|
||||
return;
|
||||
}
|
||||
|
||||
m_waiting += (signals = m_blocked);
|
||||
m_waiting += (signals = m_blocked);
|
||||
m_blocked = 0;
|
||||
}
|
||||
else
|
||||
{
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_gate), INFINITE);
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
if (m_blocked > m_gone)
|
||||
{
|
||||
if (m_gone != 0)
|
||||
{
|
||||
m_blocked -= m_gone;
|
||||
m_gone = 0;
|
||||
}
|
||||
signals = m_waiting = m_blocked;
|
||||
m_blocked = 0;
|
||||
}
|
||||
else
|
||||
else
|
||||
{
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_gate), INFINITE);
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
if (m_blocked > m_gone)
|
||||
{
|
||||
if (m_gone != 0)
|
||||
{
|
||||
m_blocked -= m_gone;
|
||||
m_gone = 0;
|
||||
}
|
||||
signals = m_waiting = m_blocked;
|
||||
m_blocked = 0;
|
||||
}
|
||||
else
|
||||
{
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0);
|
||||
assert(res);
|
||||
}
|
||||
}
|
||||
|
||||
res = ReleaseMutex(reinterpret_cast<HANDLE>(m_mutex));
|
||||
assert(res);
|
||||
|
||||
if (signals)
|
||||
{
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_queue), signals,
|
||||
0);
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0);
|
||||
assert(res);
|
||||
}
|
||||
|
||||
res = ReleaseMutex(reinterpret_cast<HANDLE>(m_mutex));
|
||||
assert(res);
|
||||
|
||||
if (signals)
|
||||
{
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_queue), signals, 0);
|
||||
assert(res);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
void condition_impl::enter_wait()
|
||||
void condition::enter_wait()
|
||||
{
|
||||
int res = 0;
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_gate), INFINITE);
|
||||
@@ -192,7 +180,7 @@ void condition_impl::enter_wait()
|
||||
assert(res);
|
||||
}
|
||||
|
||||
void condition_impl::do_wait()
|
||||
void condition::do_wait()
|
||||
{
|
||||
int res = 0;
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_queue), INFINITE);
|
||||
@@ -206,74 +194,57 @@ void condition_impl::do_wait()
|
||||
was_waiting = m_waiting;
|
||||
was_gone = m_gone;
|
||||
if (was_waiting != 0)
|
||||
{
|
||||
if (--m_waiting == 0)
|
||||
{
|
||||
if (--m_waiting == 0)
|
||||
{
|
||||
if (m_blocked != 0)
|
||||
{
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1,
|
||||
0); // open m_gate
|
||||
assert(res);
|
||||
was_waiting = 0;
|
||||
}
|
||||
else if (m_gone != 0)
|
||||
m_gone = 0;
|
||||
}
|
||||
if (m_blocked != 0)
|
||||
{
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0); // open m_gate
|
||||
assert(res);
|
||||
was_waiting = 0;
|
||||
}
|
||||
else if (m_gone != 0)
|
||||
m_gone = 0;
|
||||
}
|
||||
}
|
||||
else if (++m_gone == (std::numeric_limits<unsigned>::max() / 2))
|
||||
{
|
||||
// timeout occured, normalize the m_gone count
|
||||
// this may occur if many calls to wait with a timeout are made and
|
||||
// no call to notify_* is made
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_gate), INFINITE);
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
m_blocked -= m_gone;
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0);
|
||||
assert(res);
|
||||
m_gone = 0;
|
||||
}
|
||||
{
|
||||
// timeout occured, normalize the m_gone count
|
||||
// this may occur if many calls to wait with a timeout are made and
|
||||
// no call to notify_* is made
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_gate), INFINITE);
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
m_blocked -= m_gone;
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0);
|
||||
assert(res);
|
||||
m_gone = 0;
|
||||
}
|
||||
res = ReleaseMutex(reinterpret_cast<HANDLE>(m_mutex));
|
||||
assert(res);
|
||||
|
||||
if (was_waiting == 1)
|
||||
{
|
||||
for (/**/ ; was_gone; --was_gone)
|
||||
{
|
||||
for (/**/ ; was_gone; --was_gone)
|
||||
{
|
||||
// better now than spurious later
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_queue),
|
||||
INFINITE);
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
}
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0);
|
||||
assert(res);
|
||||
// better now than spurious later
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_queue), INFINITE);
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
}
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0);
|
||||
assert(res);
|
||||
}
|
||||
}
|
||||
|
||||
bool condition_impl::do_timed_wait(const xtime& xt)
|
||||
bool condition::do_timed_wait(const xtime& xt)
|
||||
{
|
||||
bool ret = false;
|
||||
unsigned milliseconds;
|
||||
to_duration(xt, milliseconds);
|
||||
|
||||
unsigned int res = 0;
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_queue), milliseconds);
|
||||
assert(res != WAIT_FAILED && res != WAIT_ABANDONED);
|
||||
|
||||
for (;;)
|
||||
{
|
||||
int milliseconds;
|
||||
to_duration(xt, milliseconds);
|
||||
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_queue),
|
||||
milliseconds);
|
||||
assert(res != WAIT_FAILED && res != WAIT_ABANDONED);
|
||||
ret = (res == WAIT_OBJECT_0);
|
||||
|
||||
if (res == WAIT_TIMEOUT)
|
||||
{
|
||||
xtime cur;
|
||||
xtime_get(&cur, TIME_UTC);
|
||||
if (xtime_cmp(xt, cur) > 0)
|
||||
continue;
|
||||
}
|
||||
|
||||
break;
|
||||
}
|
||||
bool ret = (res == WAIT_OBJECT_0);
|
||||
|
||||
unsigned was_waiting=0;
|
||||
unsigned was_gone=0;
|
||||
@@ -283,59 +254,57 @@ bool condition_impl::do_timed_wait(const xtime& xt)
|
||||
was_waiting = m_waiting;
|
||||
was_gone = m_gone;
|
||||
if (was_waiting != 0)
|
||||
{
|
||||
if (!ret) // timeout
|
||||
{
|
||||
if (!ret) // timeout
|
||||
{
|
||||
if (m_blocked != 0)
|
||||
--m_blocked;
|
||||
else
|
||||
++m_gone; // count spurious wakeups
|
||||
}
|
||||
if (--m_waiting == 0)
|
||||
{
|
||||
if (m_blocked != 0)
|
||||
{
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1,
|
||||
0); // open m_gate
|
||||
assert(res);
|
||||
was_waiting = 0;
|
||||
}
|
||||
else if (m_gone != 0)
|
||||
m_gone = 0;
|
||||
}
|
||||
if (m_blocked != 0)
|
||||
--m_blocked;
|
||||
else
|
||||
++m_gone; // count spurious wakeups
|
||||
}
|
||||
if (--m_waiting == 0)
|
||||
{
|
||||
if (m_blocked != 0)
|
||||
{
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0); // open m_gate
|
||||
assert(res);
|
||||
was_waiting = 0;
|
||||
}
|
||||
else if (m_gone != 0)
|
||||
m_gone = 0;
|
||||
}
|
||||
}
|
||||
else if (++m_gone == (std::numeric_limits<unsigned>::max() / 2))
|
||||
{
|
||||
// timeout occured, normalize the m_gone count
|
||||
// this may occur if many calls to wait with a timeout are made and
|
||||
// no call to notify_* is made
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_gate), INFINITE);
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
m_blocked -= m_gone;
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0);
|
||||
assert(res);
|
||||
m_gone = 0;
|
||||
}
|
||||
{
|
||||
// timeout occured, normalize the m_gone count
|
||||
// this may occur if many calls to wait with a timeout are made and
|
||||
// no call to notify_* is made
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_gate), INFINITE);
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
m_blocked -= m_gone;
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0);
|
||||
assert(res);
|
||||
m_gone = 0;
|
||||
}
|
||||
res = ReleaseMutex(reinterpret_cast<HANDLE>(m_mutex));
|
||||
assert(res);
|
||||
|
||||
if (was_waiting == 1)
|
||||
{
|
||||
for (/**/ ; was_gone; --was_gone)
|
||||
{
|
||||
for (/**/ ; was_gone; --was_gone)
|
||||
{
|
||||
// better now than spurious later
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_queue),
|
||||
INFINITE);
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
}
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0);
|
||||
assert(res);
|
||||
// better now than spurious later
|
||||
res = WaitForSingleObject(reinterpret_cast<HANDLE>(m_queue), INFINITE);
|
||||
assert(res == WAIT_OBJECT_0);
|
||||
}
|
||||
res = ReleaseSemaphore(reinterpret_cast<HANDLE>(m_gate), 1, 0);
|
||||
assert(res);
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
#elif defined(BOOST_HAS_PTHREADS)
|
||||
condition_impl::condition_impl()
|
||||
condition::condition()
|
||||
{
|
||||
int res = 0;
|
||||
res = pthread_cond_init(&m_condition, 0);
|
||||
@@ -343,35 +312,35 @@ condition_impl::condition_impl()
|
||||
throw thread_resource_error();
|
||||
}
|
||||
|
||||
condition_impl::~condition_impl()
|
||||
condition::~condition()
|
||||
{
|
||||
int res = 0;
|
||||
res = pthread_cond_destroy(&m_condition);
|
||||
assert(res == 0);
|
||||
}
|
||||
|
||||
void condition_impl::notify_one()
|
||||
void condition::notify_one()
|
||||
{
|
||||
int res = 0;
|
||||
res = pthread_cond_signal(&m_condition);
|
||||
assert(res == 0);
|
||||
}
|
||||
|
||||
void condition_impl::notify_all()
|
||||
void condition::notify_all()
|
||||
{
|
||||
int res = 0;
|
||||
res = pthread_cond_broadcast(&m_condition);
|
||||
assert(res == 0);
|
||||
}
|
||||
|
||||
void condition_impl::do_wait(pthread_mutex_t* pmutex)
|
||||
void condition::do_wait(pthread_mutex_t* pmutex)
|
||||
{
|
||||
int res = 0;
|
||||
res = pthread_cond_wait(&m_condition, pmutex);
|
||||
assert(res == 0);
|
||||
}
|
||||
|
||||
bool condition_impl::do_timed_wait(const xtime& xt, pthread_mutex_t* pmutex)
|
||||
bool condition::do_timed_wait(const xtime& xt, pthread_mutex_t* pmutex)
|
||||
{
|
||||
timespec ts;
|
||||
to_timespec(xt, ts);
|
||||
@@ -382,296 +351,10 @@ bool condition_impl::do_timed_wait(const xtime& xt, pthread_mutex_t* pmutex)
|
||||
|
||||
return res != ETIMEDOUT;
|
||||
}
|
||||
#elif defined(BOOST_HAS_MPTASKS)
|
||||
|
||||
using threads::mac::detail::safe_enter_critical_region;
|
||||
using threads::mac::detail::safe_wait_on_semaphore;
|
||||
|
||||
condition_impl::condition_impl()
|
||||
: m_gone(0), m_blocked(0), m_waiting(0)
|
||||
{
|
||||
threads::mac::detail::thread_init();
|
||||
|
||||
OSStatus lStatus = noErr;
|
||||
|
||||
lStatus = MPCreateSemaphore(1, 1, &m_gate);
|
||||
if(lStatus == noErr)
|
||||
lStatus = MPCreateSemaphore(ULONG_MAX, 0, &m_queue);
|
||||
|
||||
if(lStatus != noErr || !m_gate || !m_queue)
|
||||
{
|
||||
if (m_gate)
|
||||
{
|
||||
lStatus = MPDeleteSemaphore(m_gate);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
if (m_queue)
|
||||
{
|
||||
lStatus = MPDeleteSemaphore(m_queue);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
|
||||
throw thread_resource_error();
|
||||
}
|
||||
}
|
||||
|
||||
condition_impl::~condition_impl()
|
||||
{
|
||||
OSStatus lStatus = noErr;
|
||||
lStatus = MPDeleteSemaphore(m_gate);
|
||||
assert(lStatus == noErr);
|
||||
lStatus = MPDeleteSemaphore(m_queue);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
|
||||
void condition_impl::notify_one()
|
||||
{
|
||||
unsigned signals = 0;
|
||||
|
||||
OSStatus lStatus = noErr;
|
||||
lStatus = safe_enter_critical_region(m_mutex, kDurationForever,
|
||||
m_mutex_mutex);
|
||||
assert(lStatus == noErr);
|
||||
|
||||
if (m_waiting != 0) // the m_gate is already closed
|
||||
{
|
||||
if (m_blocked == 0)
|
||||
{
|
||||
lStatus = MPExitCriticalRegion(m_mutex);
|
||||
assert(lStatus == noErr);
|
||||
return;
|
||||
}
|
||||
|
||||
++m_waiting;
|
||||
--m_blocked;
|
||||
}
|
||||
else
|
||||
{
|
||||
lStatus = safe_wait_on_semaphore(m_gate, kDurationForever);
|
||||
assert(lStatus == noErr);
|
||||
if (m_blocked > m_gone)
|
||||
{
|
||||
if (m_gone != 0)
|
||||
{
|
||||
m_blocked -= m_gone;
|
||||
m_gone = 0;
|
||||
}
|
||||
signals = m_waiting = 1;
|
||||
--m_blocked;
|
||||
}
|
||||
else
|
||||
{
|
||||
lStatus = MPSignalSemaphore(m_gate);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
|
||||
lStatus = MPExitCriticalRegion(m_mutex);
|
||||
assert(lStatus == noErr);
|
||||
|
||||
while (signals)
|
||||
{
|
||||
lStatus = MPSignalSemaphore(m_queue);
|
||||
assert(lStatus == noErr);
|
||||
--signals;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
void condition_impl::notify_all()
|
||||
{
|
||||
unsigned signals = 0;
|
||||
|
||||
OSStatus lStatus = noErr;
|
||||
lStatus = safe_enter_critical_region(m_mutex, kDurationForever,
|
||||
m_mutex_mutex);
|
||||
assert(lStatus == noErr);
|
||||
|
||||
if (m_waiting != 0) // the m_gate is already closed
|
||||
{
|
||||
if (m_blocked == 0)
|
||||
{
|
||||
lStatus = MPExitCriticalRegion(m_mutex);
|
||||
assert(lStatus == noErr);
|
||||
return;
|
||||
}
|
||||
|
||||
m_waiting += (signals = m_blocked);
|
||||
m_blocked = 0;
|
||||
}
|
||||
else
|
||||
{
|
||||
lStatus = safe_wait_on_semaphore(m_gate, kDurationForever);
|
||||
assert(lStatus == noErr);
|
||||
if (m_blocked > m_gone)
|
||||
{
|
||||
if (m_gone != 0)
|
||||
{
|
||||
m_blocked -= m_gone;
|
||||
m_gone = 0;
|
||||
}
|
||||
signals = m_waiting = m_blocked;
|
||||
m_blocked = 0;
|
||||
}
|
||||
else
|
||||
{
|
||||
lStatus = MPSignalSemaphore(m_gate);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
|
||||
lStatus = MPExitCriticalRegion(m_mutex);
|
||||
assert(lStatus == noErr);
|
||||
|
||||
while (signals)
|
||||
{
|
||||
lStatus = MPSignalSemaphore(m_queue);
|
||||
assert(lStatus == noErr);
|
||||
--signals;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
void condition_impl::enter_wait()
|
||||
{
|
||||
OSStatus lStatus = noErr;
|
||||
lStatus = safe_wait_on_semaphore(m_gate, kDurationForever);
|
||||
assert(lStatus == noErr);
|
||||
++m_blocked;
|
||||
lStatus = MPSignalSemaphore(m_gate);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
|
||||
void condition_impl::do_wait()
|
||||
{
|
||||
OSStatus lStatus = noErr;
|
||||
lStatus = safe_wait_on_semaphore(m_queue, kDurationForever);
|
||||
assert(lStatus == noErr);
|
||||
|
||||
unsigned was_waiting=0;
|
||||
unsigned was_gone=0;
|
||||
|
||||
lStatus = safe_enter_critical_region(m_mutex, kDurationForever,
|
||||
m_mutex_mutex);
|
||||
assert(lStatus == noErr);
|
||||
was_waiting = m_waiting;
|
||||
was_gone = m_gone;
|
||||
if (was_waiting != 0)
|
||||
{
|
||||
if (--m_waiting == 0)
|
||||
{
|
||||
if (m_blocked != 0)
|
||||
{
|
||||
lStatus = MPSignalSemaphore(m_gate); // open m_gate
|
||||
assert(lStatus == noErr);
|
||||
was_waiting = 0;
|
||||
}
|
||||
else if (m_gone != 0)
|
||||
m_gone = 0;
|
||||
}
|
||||
}
|
||||
else if (++m_gone == (std::numeric_limits<unsigned>::max() / 2))
|
||||
{
|
||||
// timeout occured, normalize the m_gone count
|
||||
// this may occur if many calls to wait with a timeout are made and
|
||||
// no call to notify_* is made
|
||||
lStatus = safe_wait_on_semaphore(m_gate, kDurationForever);
|
||||
assert(lStatus == noErr);
|
||||
m_blocked -= m_gone;
|
||||
lStatus = MPSignalSemaphore(m_gate);
|
||||
assert(lStatus == noErr);
|
||||
m_gone = 0;
|
||||
}
|
||||
lStatus = MPExitCriticalRegion(m_mutex);
|
||||
assert(lStatus == noErr);
|
||||
|
||||
if (was_waiting == 1)
|
||||
{
|
||||
for (/**/ ; was_gone; --was_gone)
|
||||
{
|
||||
// better now than spurious later
|
||||
lStatus = safe_wait_on_semaphore(m_queue, kDurationForever);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
lStatus = MPSignalSemaphore(m_gate);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
}
|
||||
|
||||
bool condition_impl::do_timed_wait(const xtime& xt)
|
||||
{
|
||||
int milliseconds;
|
||||
to_duration(xt, milliseconds);
|
||||
|
||||
OSStatus lStatus = noErr;
|
||||
lStatus = safe_wait_on_semaphore(m_queue, milliseconds);
|
||||
assert(lStatus == noErr || lStatus == kMPTimeoutErr);
|
||||
|
||||
bool ret = (lStatus == noErr);
|
||||
|
||||
unsigned was_waiting=0;
|
||||
unsigned was_gone=0;
|
||||
|
||||
lStatus = safe_enter_critical_region(m_mutex, kDurationForever,
|
||||
m_mutex_mutex);
|
||||
assert(lStatus == noErr);
|
||||
was_waiting = m_waiting;
|
||||
was_gone = m_gone;
|
||||
if (was_waiting != 0)
|
||||
{
|
||||
if (!ret) // timeout
|
||||
{
|
||||
if (m_blocked != 0)
|
||||
--m_blocked;
|
||||
else
|
||||
++m_gone; // count spurious wakeups
|
||||
}
|
||||
if (--m_waiting == 0)
|
||||
{
|
||||
if (m_blocked != 0)
|
||||
{
|
||||
lStatus = MPSignalSemaphore(m_gate); // open m_gate
|
||||
assert(lStatus == noErr);
|
||||
was_waiting = 0;
|
||||
}
|
||||
else if (m_gone != 0)
|
||||
m_gone = 0;
|
||||
}
|
||||
}
|
||||
else if (++m_gone == (std::numeric_limits<unsigned>::max() / 2))
|
||||
{
|
||||
// timeout occured, normalize the m_gone count
|
||||
// this may occur if many calls to wait with a timeout are made and
|
||||
// no call to notify_* is made
|
||||
lStatus = safe_wait_on_semaphore(m_gate, kDurationForever);
|
||||
assert(lStatus == noErr);
|
||||
m_blocked -= m_gone;
|
||||
lStatus = MPSignalSemaphore(m_gate);
|
||||
assert(lStatus == noErr);
|
||||
m_gone = 0;
|
||||
}
|
||||
lStatus = MPExitCriticalRegion(m_mutex);
|
||||
assert(lStatus == noErr);
|
||||
|
||||
if (was_waiting == 1)
|
||||
{
|
||||
for (/**/ ; was_gone; --was_gone)
|
||||
{
|
||||
// better now than spurious later
|
||||
lStatus = safe_wait_on_semaphore(m_queue, kDurationForever);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
lStatus = MPSignalSemaphore(m_gate);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
|
||||
return ret;
|
||||
}
|
||||
#endif
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace boost
|
||||
|
||||
// Change Log:
|
||||
// 8 Feb 01 WEKEMPF Initial version.
|
||||
// 22 May 01 WEKEMPF Modified to use xtime for time outs.
|
||||
// 3 Jan 03 WEKEMPF Modified for DLL implementation.
|
||||
|
||||
@@ -1,4 +1,4 @@
|
||||
// Copyright (C) 2001-2003
|
||||
// Copyright (C) 2001
|
||||
// William E. Kempf
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
@@ -14,13 +14,11 @@
|
||||
|
||||
namespace boost {
|
||||
|
||||
lock_error::lock_error()
|
||||
: std::logic_error("thread lock error")
|
||||
lock_error::lock_error() : std::runtime_error("thread lock error")
|
||||
{
|
||||
}
|
||||
|
||||
thread_resource_error::thread_resource_error()
|
||||
: std::runtime_error("thread resource error")
|
||||
thread_resource_error::thread_resource_error() : std::runtime_error("thread resource error")
|
||||
{
|
||||
}
|
||||
|
||||
|
||||
@@ -1,14 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#define TARGET_CARBON 1
|
||||
@@ -1,72 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#include "delivery_man.hpp"
|
||||
|
||||
#include "os.hpp"
|
||||
#include "execution_context.hpp"
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
delivery_man::delivery_man():
|
||||
m_pPackage(NULL),
|
||||
m_pSemaphore(kInvalidID),
|
||||
m_bPackageWaiting(false)
|
||||
{
|
||||
assert(at_st());
|
||||
|
||||
OSStatus lStatus = MPCreateSemaphore(1UL, 0UL, &m_pSemaphore);
|
||||
// TODO - throw on error here
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
|
||||
delivery_man::~delivery_man()
|
||||
{
|
||||
assert(m_bPackageWaiting == false);
|
||||
|
||||
OSStatus lStatus = MPDeleteSemaphore(m_pSemaphore);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
|
||||
|
||||
void delivery_man::accept_deliveries()
|
||||
{
|
||||
if(m_bPackageWaiting)
|
||||
{
|
||||
assert(m_pPackage != NULL);
|
||||
m_pPackage->accept();
|
||||
m_pPackage = NULL;
|
||||
m_bPackageWaiting = false;
|
||||
|
||||
// signal to the thread making the call that we're done
|
||||
OSStatus lStatus = MPSignalSemaphore(m_pSemaphore);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
@@ -1,90 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_DELIVERY_MAN_MJM012402_HPP
|
||||
#define BOOST_DELIVERY_MAN_MJM012402_HPP
|
||||
|
||||
|
||||
#include <boost/function.hpp>
|
||||
#include <boost/utility.hpp>
|
||||
|
||||
#include <boost/thread/mutex.hpp>
|
||||
|
||||
#include "package.hpp"
|
||||
|
||||
#include <Multiprocessing.h>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
// class delivery_man is intended to move boost::function objects from MP tasks to
|
||||
// other execution contexts (such as deferred task time or system task time).
|
||||
|
||||
class delivery_man: private noncopyable
|
||||
{
|
||||
public:
|
||||
delivery_man();
|
||||
~delivery_man();
|
||||
|
||||
public:
|
||||
template<class R>
|
||||
R deliver(function<R> &rFunctor);
|
||||
|
||||
void accept_deliveries();
|
||||
|
||||
private:
|
||||
base_package *m_pPackage;
|
||||
mutex m_oMutex;
|
||||
MPSemaphoreID m_pSemaphore;
|
||||
bool m_bPackageWaiting;
|
||||
};
|
||||
|
||||
|
||||
template<class R>
|
||||
R delivery_man::deliver(function<R> &rFunctor)
|
||||
{
|
||||
assert(at_mp());
|
||||
|
||||
// lock our mutex
|
||||
mutex::scoped_lock oLock(m_oMutex);
|
||||
|
||||
// create a package and save it
|
||||
package<R> oPackage(rFunctor);
|
||||
m_pPackage = &oPackage;
|
||||
m_bPackageWaiting = true;
|
||||
|
||||
// wait on the semaphore
|
||||
OSStatus lStatus = MPWaitOnSemaphore(m_pSemaphore, kDurationForever);
|
||||
assert(lStatus == noErr);
|
||||
|
||||
return(oPackage.return_value());
|
||||
}
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_DELIVERY_MAN_MJM012402_HPP
|
||||
@@ -1,99 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#include "dt_scheduler.hpp"
|
||||
|
||||
#include "ot_context.hpp"
|
||||
|
||||
|
||||
#include <boost/thread/detail/singleton.hpp>
|
||||
|
||||
#include <OpenTransportProtocol.h>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
const OTTimeout k_ulTimerTaskDelay = 1UL;
|
||||
|
||||
|
||||
dt_scheduler::dt_scheduler():
|
||||
m_bReschedule(false),
|
||||
m_uppTask(NULL),
|
||||
m_lTask(0UL)
|
||||
{
|
||||
using ::boost::detail::thread::singleton;
|
||||
|
||||
ot_context &rContext(singleton<ot_context>::instance());
|
||||
|
||||
m_uppTask = NewOTProcessUPP(task_entry);
|
||||
m_lTask = OTCreateTimerTaskInContext(m_uppTask, this, rContext.get_context());
|
||||
}
|
||||
|
||||
dt_scheduler::~dt_scheduler()
|
||||
{
|
||||
OTDestroyTimerTask(m_lTask);
|
||||
m_lTask = 0UL;
|
||||
DisposeOTProcessUPP(m_uppTask);
|
||||
m_uppTask = NULL;
|
||||
}
|
||||
|
||||
|
||||
void dt_scheduler::start_polling()
|
||||
{
|
||||
m_bReschedule = true;
|
||||
schedule_task();
|
||||
}
|
||||
|
||||
void dt_scheduler::stop_polling()
|
||||
{
|
||||
m_bReschedule = false;
|
||||
}
|
||||
|
||||
|
||||
void dt_scheduler::schedule_task()
|
||||
{
|
||||
if(m_bReschedule)
|
||||
{
|
||||
OTScheduleTimerTask(m_lTask, k_ulTimerTaskDelay);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
/*static*/ pascal void dt_scheduler::task_entry(void *pRefCon)
|
||||
{
|
||||
dt_scheduler *pThis = reinterpret_cast<dt_scheduler *>(pRefCon);
|
||||
assert(pThis != NULL);
|
||||
pThis->task();
|
||||
}
|
||||
|
||||
void dt_scheduler::task()
|
||||
{
|
||||
periodic_function();
|
||||
schedule_task();
|
||||
}
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
@@ -1,69 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_DT_SCHEDULER_MJM012402_HPP
|
||||
#define BOOST_DT_SCHEDULER_MJM012402_HPP
|
||||
|
||||
|
||||
#include "periodical.hpp"
|
||||
|
||||
#include <OpenTransport.h>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
// class dt_scheduler calls its pure-virtual periodic_function method periodically at
|
||||
// deferred task time. This is generally 1kHz under Mac OS 9.
|
||||
|
||||
class dt_scheduler
|
||||
{
|
||||
public:
|
||||
dt_scheduler();
|
||||
virtual ~dt_scheduler();
|
||||
|
||||
protected:
|
||||
void start_polling();
|
||||
void stop_polling();
|
||||
|
||||
private:
|
||||
virtual void periodic_function() = 0;
|
||||
|
||||
private:
|
||||
void schedule_task();
|
||||
static pascal void task_entry(void *pRefCon);
|
||||
void task();
|
||||
|
||||
private:
|
||||
bool m_bReschedule;
|
||||
OTProcessUPP m_uppTask;
|
||||
long m_lTask;
|
||||
};
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_DT_SCHEDULER_MJM012402_HPP
|
||||
@@ -1,66 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#include <Debugging.h>
|
||||
#include <Multiprocessing.h>
|
||||
|
||||
#include "execution_context.hpp"
|
||||
#include "init.hpp"
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
|
||||
execution_context_t execution_context()
|
||||
{
|
||||
// make sure that MP services are available the first time through
|
||||
static bool bIgnored = detail::thread_init();
|
||||
|
||||
// first check if we're an MP task
|
||||
if(MPTaskIsPreemptive(kInvalidID))
|
||||
{
|
||||
return(k_eExecutionContextMPTask);
|
||||
}
|
||||
|
||||
#if TARGET_CARBON
|
||||
// Carbon has TaskLevel
|
||||
UInt32 ulLevel = TaskLevel();
|
||||
|
||||
if(ulLevel == 0UL)
|
||||
{
|
||||
return(k_eExecutionContextSystemTask);
|
||||
}
|
||||
|
||||
if(ulLevel & kInDeferredTaskMask)
|
||||
{
|
||||
return(k_eExecutionContextDeferredTask);
|
||||
}
|
||||
|
||||
return(k_eExecutionContextOther);
|
||||
#else
|
||||
// this can be implemented using TaskLevel if you don't mind linking against
|
||||
// DebugLib (and therefore breaking Mac OS 8.6 support), or CurrentExecutionLevel.
|
||||
# error execution_context unimplimented
|
||||
#endif
|
||||
}
|
||||
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
@@ -1,53 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_EXECUTION_CONTEXT_MJM012402_HPP
|
||||
#define BOOST_EXECUTION_CONTEXT_MJM012402_HPP
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
|
||||
// utility functions for figuring out what context your code is executing in.
|
||||
// Bear in mind that at_mp and in_blue are the only functions guarenteed by
|
||||
// Apple to work. There is simply no way of being sure that you will not get
|
||||
// false readings about task level at interrupt time in blue.
|
||||
|
||||
typedef enum {
|
||||
k_eExecutionContextSystemTask,
|
||||
k_eExecutionContextDeferredTask,
|
||||
k_eExecutionContextMPTask,
|
||||
k_eExecutionContextOther
|
||||
} execution_context_t;
|
||||
|
||||
execution_context_t execution_context();
|
||||
|
||||
inline bool at_st()
|
||||
{ return(execution_context() == k_eExecutionContextSystemTask); }
|
||||
|
||||
inline bool at_mp()
|
||||
{ return(execution_context() == k_eExecutionContextMPTask); }
|
||||
inline bool in_blue()
|
||||
{ return(!at_mp()); }
|
||||
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
#endif // BOOST_EXECUTION_CONTEXT_MJM012402_HPP
|
||||
@@ -1,64 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#include "init.hpp"
|
||||
|
||||
#include "remote_call_manager.hpp"
|
||||
|
||||
|
||||
#include <boost/thread/detail/singleton.hpp>
|
||||
|
||||
#include <Multiprocessing.h>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
namespace {
|
||||
|
||||
// force these to get called by the end of static initialization time.
|
||||
static bool g_bInitialized = (thread_init() && create_singletons());
|
||||
|
||||
}
|
||||
|
||||
|
||||
bool thread_init()
|
||||
{
|
||||
static bool bResult = MPLibraryIsLoaded();
|
||||
|
||||
return(bResult);
|
||||
}
|
||||
|
||||
bool create_singletons()
|
||||
{
|
||||
using ::boost::detail::thread::singleton;
|
||||
|
||||
singleton<remote_call_manager>::instance();
|
||||
|
||||
return(true);
|
||||
}
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
@@ -1,40 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_INIT_MJM012402_HPP
|
||||
#define BOOST_INIT_MJM012402_HPP
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
bool thread_init();
|
||||
bool create_singletons();
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_INIT_MJM012402_HPP
|
||||
@@ -1,30 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#include <cassert>
|
||||
#include <cstdio>
|
||||
|
||||
#include <MacTypes.h>
|
||||
|
||||
#include "remote_calls.hpp"
|
||||
|
||||
// this function will be called when an assertion fails. We redirect the assertion
|
||||
// to DebugStr (MacsBug under Mac OS 1.x-9.x, Console under Mac OS X).
|
||||
void __assertion_failed(char const *pszAssertion, char const *pszFile, int nLine)
|
||||
{
|
||||
using std::snprintf;
|
||||
unsigned char strlDebug[sizeof(Str255) + 1];
|
||||
char *pszDebug = reinterpret_cast<char *>(&strlDebug[1]);
|
||||
strlDebug[0] = snprintf(pszDebug, sizeof(Str255), "assertion failed: \"%s\", %s, line %d", pszAssertion, pszFile, nLine);
|
||||
boost::threads::mac::dt_remote_call(DebugStr, static_cast<ConstStringPtr>(strlDebug));
|
||||
}
|
||||
@@ -1,134 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
//
|
||||
// includes
|
||||
//
|
||||
|
||||
#include <abort_exit.h>
|
||||
#include <console.h>
|
||||
#include <console_io.h>
|
||||
#include <misc_io.h>
|
||||
#include <SIOUX.h>
|
||||
|
||||
#include "remote_calls.hpp"
|
||||
|
||||
|
||||
//
|
||||
// using declarations
|
||||
//
|
||||
|
||||
using std::__file_handle;
|
||||
using std::__idle_proc;
|
||||
using std::__io_error;
|
||||
using std::__no_io_error;
|
||||
using std::size_t;
|
||||
|
||||
using boost::threads::mac::st_remote_call;
|
||||
|
||||
|
||||
//
|
||||
// prototypes
|
||||
//
|
||||
|
||||
static bool check_console();
|
||||
static int do_read_console(__file_handle ulHandle, unsigned char *pBuffer, size_t *pCount, __idle_proc pfnIdleProc);
|
||||
static int do_write_console(__file_handle ulHandle, unsigned char *pBuffer, size_t *pCount, __idle_proc pfnIdleProc);
|
||||
|
||||
|
||||
//
|
||||
// MSL function replacements
|
||||
//
|
||||
|
||||
// these two functions are called by cin and cout, respectively, as well as by (all?)
|
||||
// other functions in MSL that do console I/O. All that they do is as the remote
|
||||
// call manager to ensure that their guts are called at system task time.
|
||||
int __read_console(__file_handle handle, unsigned char * buffer, size_t * count, __idle_proc idle_proc)
|
||||
{
|
||||
return(st_remote_call(do_read_console, handle, buffer, count, idle_proc));
|
||||
}
|
||||
|
||||
int __write_console(__file_handle handle, unsigned char * buffer, size_t * count, __idle_proc idle_proc)
|
||||
{
|
||||
return(st_remote_call(do_write_console, handle, buffer, count, idle_proc));
|
||||
}
|
||||
|
||||
|
||||
//
|
||||
// implementations
|
||||
//
|
||||
|
||||
static bool check_console()
|
||||
{
|
||||
static bool s_bHaveConsole(false);
|
||||
static bool s_bWontHaveConsole(false);
|
||||
|
||||
if(s_bHaveConsole)
|
||||
{
|
||||
return(true);
|
||||
}
|
||||
|
||||
if(s_bWontHaveConsole == false)
|
||||
{
|
||||
__stdio_atexit();
|
||||
|
||||
if(InstallConsole(0) != 0)
|
||||
{
|
||||
s_bWontHaveConsole = true;
|
||||
return(false);
|
||||
}
|
||||
__console_exit = RemoveConsole;
|
||||
s_bHaveConsole = true;
|
||||
return(true);
|
||||
}
|
||||
|
||||
return(false);
|
||||
}
|
||||
|
||||
|
||||
int do_read_console(__file_handle /*ulHandle*/, unsigned char *pBuffer, size_t *pCount, __idle_proc /*pfnIdleProc*/)
|
||||
{
|
||||
assert(pCount != NULL);
|
||||
assert(pBuffer != NULL || *pCount == 0UL);
|
||||
|
||||
if(check_console() == false)
|
||||
{
|
||||
return(__io_error);
|
||||
}
|
||||
std::fflush(stdout);
|
||||
long lCount = ReadCharsFromConsole(reinterpret_cast<char *>(pBuffer), static_cast<long>(*pCount));
|
||||
*pCount = static_cast<size_t>(lCount);
|
||||
if(lCount == -1L)
|
||||
{
|
||||
return(__io_error);
|
||||
}
|
||||
|
||||
return(__no_io_error);
|
||||
}
|
||||
|
||||
int do_write_console(__file_handle /*ulHandle*/, unsigned char *pBuffer, size_t *pCount, __idle_proc /*pfnIdleProc*/)
|
||||
{
|
||||
if(check_console() == false)
|
||||
{
|
||||
return(__io_error);
|
||||
}
|
||||
|
||||
long lCount = WriteCharsToConsole(reinterpret_cast<char *>(pBuffer), static_cast<long>(*pCount));
|
||||
*pCount = static_cast<size_t>(lCount);
|
||||
if(lCount == -1L)
|
||||
{
|
||||
return(__io_error);
|
||||
}
|
||||
|
||||
return(__no_io_error);
|
||||
}
|
||||
@@ -1,58 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
//
|
||||
// includes
|
||||
//
|
||||
|
||||
#include <cstdlib>
|
||||
|
||||
#include <Multiprocessing.h>
|
||||
|
||||
|
||||
//
|
||||
// using declarations
|
||||
//
|
||||
|
||||
using std::size_t;
|
||||
|
||||
|
||||
extern "C" {
|
||||
|
||||
//
|
||||
// prototypes
|
||||
//
|
||||
|
||||
void *malloc(size_t ulSize);
|
||||
void free(void *pBlock);
|
||||
|
||||
}
|
||||
|
||||
|
||||
//
|
||||
// MSL function replacements
|
||||
//
|
||||
|
||||
// all allocation/deallocation currently goes through MPAllocateAligned/MPFree. This
|
||||
// solution is sub-optimal at best, but will have to do for now.
|
||||
void *malloc(size_t ulSize)
|
||||
{
|
||||
static bool bIgnored = MPLibraryIsLoaded();
|
||||
return(MPAllocateAligned(ulSize, kMPAllocateDefaultAligned, 0UL));
|
||||
}
|
||||
|
||||
void free(void *pBlock)
|
||||
{
|
||||
if(pBlock == NULL) return;
|
||||
MPFree(pBlock);
|
||||
}
|
||||
@@ -1,105 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
//
|
||||
// includes
|
||||
//
|
||||
|
||||
#include <new>
|
||||
|
||||
#include <Multiprocessing.h>
|
||||
|
||||
|
||||
//
|
||||
// using declarations
|
||||
//
|
||||
|
||||
using std::size_t;
|
||||
using std::bad_alloc;
|
||||
using std::nothrow_t;
|
||||
using std::nothrow;
|
||||
|
||||
|
||||
//
|
||||
// local utility functions
|
||||
//
|
||||
|
||||
// all allocation/deallocation currently goes through MPAllocateAligned/MPFree. This
|
||||
// solution is sub-optimal at best, but will have to do for now.
|
||||
inline static void *allocate(size_t ulSize, const nothrow_t &)
|
||||
{
|
||||
static bool bIgnored = MPLibraryIsLoaded();
|
||||
return(MPAllocateAligned(ulSize, kMPAllocateDefaultAligned, 0UL));
|
||||
}
|
||||
|
||||
inline static void *allocate(size_t ulSize)
|
||||
{
|
||||
void *pBlock = allocate(ulSize, nothrow);
|
||||
if(pBlock == NULL)
|
||||
throw(bad_alloc());
|
||||
return(pBlock);
|
||||
}
|
||||
|
||||
inline static void deallocate(void *pBlock)
|
||||
{
|
||||
if(pBlock == NULL) return;
|
||||
MPFree(pBlock);
|
||||
}
|
||||
|
||||
|
||||
//
|
||||
// global operators
|
||||
//
|
||||
|
||||
void *operator new(size_t ulSize)
|
||||
{
|
||||
return(allocate(ulSize));
|
||||
}
|
||||
|
||||
void *operator new[](size_t ulSize)
|
||||
{
|
||||
return(allocate(ulSize));
|
||||
}
|
||||
|
||||
|
||||
void *operator new(size_t ulSize, const nothrow_t &rNoThrow)
|
||||
{
|
||||
return(allocate(ulSize, rNoThrow));
|
||||
}
|
||||
|
||||
void *operator new[](size_t ulSize, const nothrow_t &rNoThrow)
|
||||
{
|
||||
return(allocate(ulSize, rNoThrow));
|
||||
}
|
||||
|
||||
|
||||
void operator delete(void *pBlock)
|
||||
{
|
||||
deallocate(pBlock);
|
||||
}
|
||||
|
||||
void operator delete[](void *pBlock)
|
||||
{
|
||||
deallocate(pBlock);
|
||||
}
|
||||
|
||||
|
||||
void operator delete(void *pBlock, const nothrow_t &)
|
||||
{
|
||||
deallocate(pBlock);
|
||||
}
|
||||
|
||||
void operator delete[](void *pBlock, const nothrow_t &)
|
||||
{
|
||||
deallocate(pBlock);
|
||||
}
|
||||
@@ -1,156 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#include <cassert>
|
||||
// we include timesize.mac.h to get whether or not __TIMESIZE_DOUBLE__ is
|
||||
// defined. This is not safe, given that __TIMESIZE_DOUBLE__ affects MSL
|
||||
// at MSL's compile time, not ours, so be forgiving if you have changed it
|
||||
// since you have built MSL.
|
||||
#include <timesize.mac.h>
|
||||
#include <time.h>
|
||||
|
||||
#include <boost/thread/detail/force_cast.hpp>
|
||||
#include <boost/thread/xtime.hpp>
|
||||
|
||||
#include "execution_context.hpp"
|
||||
|
||||
#include <DriverServices.h>
|
||||
|
||||
|
||||
extern "C"
|
||||
{
|
||||
clock_t __get_clock();
|
||||
time_t __get_time();
|
||||
int __to_gm_time(time_t *pTime);
|
||||
int __is_dst();
|
||||
}
|
||||
|
||||
|
||||
static inline uint64_t get_nanoseconds()
|
||||
{
|
||||
using boost::detail::thread::force_cast;
|
||||
return(force_cast<uint64_t>(AbsoluteToNanoseconds(UpTime())));
|
||||
}
|
||||
|
||||
|
||||
#ifdef __TIMESIZE_DOUBLE__
|
||||
|
||||
// return number of microseconds since startup as a double
|
||||
clock_t __get_clock()
|
||||
{
|
||||
static const double k_dNanosecondsPerMicrosecond(1000.0);
|
||||
|
||||
return(get_nanoseconds() / k_dNanosecondsPerMicrosecond);
|
||||
}
|
||||
|
||||
#else
|
||||
|
||||
// return number of ticks (60th of a second) since startup as a long
|
||||
clock_t __get_clock()
|
||||
{
|
||||
static const uint64_t k_ullTicksPerSecond(60ULL);
|
||||
static const uint64_t k_ullNanosecondsPerSecond(1000ULL * 1000ULL * 1000ULL);
|
||||
static const uint64_t k_ullNanosecondsPerTick(k_ullNanosecondsPerSecond / k_ullTicksPerSecond);
|
||||
|
||||
return(get_nanoseconds() / k_ullNanosecondsPerTick);
|
||||
}
|
||||
|
||||
#endif
|
||||
|
||||
// return number of seconds elapsed since Jan 1, 1970
|
||||
time_t __get_time()
|
||||
{
|
||||
boost::xtime sTime;
|
||||
int nType = boost::xtime_get(&sTime, boost::TIME_UTC);
|
||||
assert(nType == boost::TIME_UTC);
|
||||
return(static_cast<time_t>(sTime.sec));
|
||||
}
|
||||
|
||||
|
||||
static inline MachineLocation &read_location()
|
||||
{
|
||||
static MachineLocation s_sLocation;
|
||||
assert(boost::threads::mac::at_st());
|
||||
ReadLocation(&s_sLocation);
|
||||
return(s_sLocation);
|
||||
}
|
||||
|
||||
static inline MachineLocation &get_location()
|
||||
{
|
||||
static MachineLocation &s_rLocation(read_location());
|
||||
return(s_rLocation);
|
||||
}
|
||||
|
||||
|
||||
// force the machine location to be cached at static initlialization
|
||||
static MachineLocation &g_rIgnored(get_location());
|
||||
|
||||
static inline long calculate_delta()
|
||||
{
|
||||
MachineLocation &rLocation(get_location());
|
||||
|
||||
// gmtDelta is a 24-bit, signed integer. We need to strip out the lower 24 bits,
|
||||
// then sign-extend what we have.
|
||||
long lDelta = rLocation.u.gmtDelta & 0x00ffffffL;
|
||||
if((lDelta & 0x00800000L) != 0L)
|
||||
{
|
||||
lDelta |= 0xFF000000;
|
||||
}
|
||||
return(lDelta);
|
||||
}
|
||||
|
||||
static inline bool check_if_location_is_broken()
|
||||
{
|
||||
MachineLocation &rLocation(get_location());
|
||||
if(rLocation.latitude == 0 && rLocation.longitude == 0 && rLocation.u.gmtDelta == 0)
|
||||
return(true);
|
||||
return(false);
|
||||
}
|
||||
|
||||
static inline bool location_is_broken()
|
||||
{
|
||||
static bool s_bLocationIsBroken(check_if_location_is_broken());
|
||||
return(s_bLocationIsBroken);
|
||||
}
|
||||
|
||||
|
||||
// translate time to GMT
|
||||
int __to_gm_time(time_t *pTime)
|
||||
{
|
||||
if(location_is_broken())
|
||||
{
|
||||
return(0);
|
||||
}
|
||||
|
||||
static long s_lDelta(calculate_delta());
|
||||
*pTime -= s_lDelta;
|
||||
return(1);
|
||||
}
|
||||
|
||||
|
||||
static inline bool is_daylight_savings_time()
|
||||
{
|
||||
MachineLocation &rLocation(get_location());
|
||||
return(rLocation.u.dlsDelta != 0);
|
||||
}
|
||||
|
||||
// check if we're in daylight savings time
|
||||
int __is_dst()
|
||||
{
|
||||
if(location_is_broken())
|
||||
{
|
||||
return(-1);
|
||||
}
|
||||
static bool bIsDaylightSavingsTime(is_daylight_savings_time());
|
||||
return(static_cast<int>(bIsDaylightSavingsTime));
|
||||
}
|
||||
@@ -1,63 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#include "os.hpp"
|
||||
|
||||
|
||||
#include <cassert>
|
||||
|
||||
#include <Gestalt.h>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace os {
|
||||
|
||||
|
||||
// read the OS version from Gestalt
|
||||
static inline long get_version()
|
||||
{
|
||||
long lVersion;
|
||||
OSErr nErr = Gestalt(gestaltSystemVersion, &lVersion);
|
||||
assert(nErr == noErr);
|
||||
return(lVersion);
|
||||
}
|
||||
|
||||
|
||||
// check if we're running under Mac OS X and cache that information
|
||||
bool x()
|
||||
{
|
||||
static bool bX = (version() >= 0x1000);
|
||||
return(bX);
|
||||
}
|
||||
|
||||
|
||||
// read the OS version and cache it
|
||||
long version()
|
||||
{
|
||||
static long lVersion = get_version();
|
||||
return(lVersion);
|
||||
}
|
||||
|
||||
|
||||
} // namespace os
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
@@ -1,43 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_OS_MJM012402_HPP
|
||||
#define BOOST_OS_MJM012402_HPP
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace os {
|
||||
|
||||
|
||||
// functions to determine the OS environment. With namespaces, you get a cute call:
|
||||
// mac::os::x
|
||||
|
||||
bool x();
|
||||
long version();
|
||||
|
||||
|
||||
} // namespace os
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_OS_MJM012402_HPP
|
||||
@@ -1,52 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#include "ot_context.hpp"
|
||||
|
||||
#include "execution_context.hpp"
|
||||
|
||||
|
||||
#include <cassert>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
ot_context::ot_context()
|
||||
{
|
||||
assert(at_st());
|
||||
|
||||
OSStatus lStatus = InitOpenTransportInContext(0UL, &m_pContext);
|
||||
// TODO - throw on error
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
|
||||
ot_context::~ot_context()
|
||||
{
|
||||
CloseOpenTransportInContext(m_pContext);
|
||||
}
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
@@ -1,64 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_OT_CONTEXT_MJM012402_HPP
|
||||
#define BOOST_OT_CONTEXT_MJM012402_HPP
|
||||
|
||||
|
||||
#include <OpenTransport.h>
|
||||
|
||||
#include <boost/utility.hpp>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
// class ot_context is intended to be used only as a singleton. All that this class
|
||||
// does is ask OpenTransport to create him an OTClientContextPtr, and then doles
|
||||
// this out to anyone who wants it. ot_context should only be instantiated at
|
||||
// system task time.
|
||||
|
||||
class ot_context: private noncopyable
|
||||
{
|
||||
protected:
|
||||
ot_context();
|
||||
~ot_context();
|
||||
|
||||
public:
|
||||
OTClientContextPtr get_context();
|
||||
|
||||
private:
|
||||
OTClientContextPtr m_pContext;
|
||||
};
|
||||
|
||||
|
||||
inline OTClientContextPtr ot_context::get_context()
|
||||
{ return(m_pContext); }
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_OT_CONTEXT_MJM012402_HPP
|
||||
@@ -1,82 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_PACKAGE_MJM012402_HPP
|
||||
#define BOOST_PACKAGE_MJM012402_HPP
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
class base_package: private noncopyable
|
||||
{
|
||||
public:
|
||||
virtual void accept() = 0;
|
||||
};
|
||||
|
||||
template<class R>
|
||||
class package: public base_package
|
||||
{
|
||||
public:
|
||||
inline package(function<R> &rFunctor):
|
||||
m_rFunctor(rFunctor)
|
||||
{ /* no-op */ }
|
||||
inline ~package()
|
||||
{ /* no-op */ }
|
||||
|
||||
virtual void accept()
|
||||
{ m_oR = m_rFunctor(); }
|
||||
inline R return_value()
|
||||
{ return(m_oR); }
|
||||
|
||||
private:
|
||||
function<R> &m_rFunctor;
|
||||
R m_oR;
|
||||
};
|
||||
|
||||
template<>
|
||||
class package<void>: public base_package
|
||||
{
|
||||
public:
|
||||
inline package(function<void> &rFunctor):
|
||||
m_rFunctor(rFunctor)
|
||||
{ /* no-op */ }
|
||||
inline ~package()
|
||||
{ /* no-op */ }
|
||||
|
||||
virtual void accept()
|
||||
{ m_rFunctor(); }
|
||||
inline void return_value()
|
||||
{ return; }
|
||||
|
||||
private:
|
||||
function<void> &m_rFunctor;
|
||||
};
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_PACKAGE_MJM012402_HPP
|
||||
@@ -1,103 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_PERIODICAL_MJM012402_HPP
|
||||
#define BOOST_PERIODICAL_MJM012402_HPP
|
||||
|
||||
|
||||
#include <boost/function.hpp>
|
||||
#include <boost/utility.hpp>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
// class periodical inherits from its template parameter, which should follow the
|
||||
// pattern set by classes dt_scheduler and st_scheduler. periodical knows how to
|
||||
// call a boost::function, where the xx_scheduler classes only know to to call a
|
||||
// member periodically.
|
||||
|
||||
template<class Scheduler>
|
||||
class periodical: private noncopyable, private Scheduler
|
||||
{
|
||||
public:
|
||||
periodical(function<void> &rFunction);
|
||||
~periodical();
|
||||
|
||||
public:
|
||||
void start();
|
||||
void stop();
|
||||
|
||||
protected:
|
||||
virtual void periodic_function();
|
||||
|
||||
private:
|
||||
function<void> m_oFunction;
|
||||
};
|
||||
|
||||
|
||||
template<class Scheduler>
|
||||
periodical<Scheduler>::periodical(function<void> &rFunction):
|
||||
m_oFunction(rFunction)
|
||||
{
|
||||
// no-op
|
||||
}
|
||||
|
||||
template<class Scheduler>
|
||||
periodical<Scheduler>::~periodical()
|
||||
{
|
||||
stop();
|
||||
}
|
||||
|
||||
template<class Scheduler>
|
||||
void periodical<Scheduler>::start()
|
||||
{
|
||||
start_polling();
|
||||
}
|
||||
|
||||
template<class Scheduler>
|
||||
void periodical<Scheduler>::stop()
|
||||
{
|
||||
stop_polling();
|
||||
}
|
||||
|
||||
|
||||
template<class Scheduler>
|
||||
inline void periodical<Scheduler>::periodic_function()
|
||||
{
|
||||
try
|
||||
{
|
||||
m_oFunction();
|
||||
}
|
||||
catch(...)
|
||||
{
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_PERIODICAL_MJM012402_HPP
|
||||
@@ -1,15 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#define NDEBUG
|
||||
#define TARGET_CARBON 1
|
||||
@@ -1,54 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#include "remote_call_manager.hpp"
|
||||
|
||||
#include <boost/bind.hpp>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
using detail::delivery_man;
|
||||
|
||||
|
||||
remote_call_manager::remote_call_manager():
|
||||
m_oDTDeliveryMan(),
|
||||
m_oSTDeliveryMan(),
|
||||
m_oDTFunction(bind(&delivery_man::accept_deliveries, &m_oDTDeliveryMan)),
|
||||
m_oSTFunction(bind(&delivery_man::accept_deliveries, &m_oSTDeliveryMan)),
|
||||
m_oDTPeriodical(m_oDTFunction),
|
||||
m_oSTPeriodical(m_oSTFunction)
|
||||
{
|
||||
m_oDTPeriodical.start();
|
||||
m_oSTPeriodical.start();
|
||||
}
|
||||
|
||||
remote_call_manager::~remote_call_manager()
|
||||
{
|
||||
}
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
@@ -1,108 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_REMOTE_CALL_MANAGER_MJM012402_HPP
|
||||
#define BOOST_REMOTE_CALL_MANAGER_MJM012402_HPP
|
||||
|
||||
|
||||
#include <boost/utility.hpp>
|
||||
|
||||
#include "delivery_man.hpp"
|
||||
#include "dt_scheduler.hpp"
|
||||
#include "periodical.hpp"
|
||||
#include "execution_context.hpp"
|
||||
#include "st_scheduler.hpp"
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
// class remote_call_manager is used by the remote call functions (dt_remote_call and
|
||||
// st_remote_call) to execute functions in non-MP contexts.
|
||||
|
||||
class remote_call_manager: private noncopyable
|
||||
{
|
||||
protected:
|
||||
remote_call_manager();
|
||||
~remote_call_manager();
|
||||
|
||||
public:
|
||||
template<class R>
|
||||
R execute_at_dt(function<R> &rFunctor);
|
||||
template<class R>
|
||||
R execute_at_st(function<R> &rFunctor);
|
||||
|
||||
private:
|
||||
template<class R>
|
||||
static R execute_now(function<R> &rFunctor);
|
||||
|
||||
private:
|
||||
delivery_man m_oDTDeliveryMan;
|
||||
delivery_man m_oSTDeliveryMan;
|
||||
function<void> m_oDTFunction;
|
||||
function<void> m_oSTFunction;
|
||||
periodical<dt_scheduler> m_oDTPeriodical;
|
||||
periodical<st_scheduler> m_oSTPeriodical;
|
||||
};
|
||||
|
||||
|
||||
template<class R>
|
||||
/*static*/ inline R remote_call_manager::execute_now(function<R> &rFunctor)
|
||||
{
|
||||
return(rFunctor());
|
||||
}
|
||||
template<>
|
||||
/*static*/ inline void remote_call_manager::execute_now<void>(function<void> &rFunctor)
|
||||
{
|
||||
rFunctor();
|
||||
}
|
||||
|
||||
|
||||
template<class R>
|
||||
inline R remote_call_manager::execute_at_dt(function<R> &rFunctor)
|
||||
{
|
||||
if(at_mp())
|
||||
{
|
||||
return(m_oDTDeliveryMan.deliver(rFunctor));
|
||||
}
|
||||
return(execute_now(rFunctor));
|
||||
}
|
||||
|
||||
template<class R>
|
||||
inline R remote_call_manager::execute_at_st(function<R> &rFunctor)
|
||||
{
|
||||
if(at_mp())
|
||||
{
|
||||
return(m_oSTDeliveryMan.deliver(rFunctor));
|
||||
}
|
||||
assert(at_st());
|
||||
return(execute_now(rFunctor));
|
||||
}
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_REMOTE_CALL_MANAGER_MJM012402_HPP
|
||||
@@ -1,163 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_REMOTE_CALLS_MJM012402_HPP
|
||||
#define BOOST_REMOTE_CALLS_MJM012402_HPP
|
||||
|
||||
|
||||
#include <boost/bind.hpp>
|
||||
|
||||
#include "remote_call_manager.hpp"
|
||||
#include <boost/thread/detail/singleton.hpp>
|
||||
|
||||
|
||||
// this file contains macros to generate functions with the signatures:
|
||||
// ReturnType st_remote_call([pascal] ReturnType (*pfnFunction)(
|
||||
// [Argument1Type[, Argument2Type[...]]])
|
||||
// [, Argument1Type oArgument1[, Argument2Type oArgument2[...]]])
|
||||
// and
|
||||
// ReturnType dt_remote_call([pascal] ReturnType (*pfnFunction)(
|
||||
// [Argument1Type[, Argument2Type[...]]])
|
||||
// [, Argument1Type oArgument1[, Argument2Type oArgument2[...]]])
|
||||
// in other words, identical to the function pointer versions of boost::bind, but
|
||||
// with the return type returned. The purpose of these functions is to be able to
|
||||
// request that a function be called at system task time or deferred task time, then
|
||||
// sleep until it is called, and finally get back its return value.
|
||||
|
||||
#define BOOST_REMOTE_CALL_CLASS_LIST_0
|
||||
#define BOOST_REMOTE_CALL_CLASS_LIST_1 BOOST_REMOTE_CALL_CLASS_LIST_0, class A1
|
||||
#define BOOST_REMOTE_CALL_CLASS_LIST_2 BOOST_REMOTE_CALL_CLASS_LIST_1, class A2
|
||||
#define BOOST_REMOTE_CALL_CLASS_LIST_3 BOOST_REMOTE_CALL_CLASS_LIST_2, class A3
|
||||
#define BOOST_REMOTE_CALL_CLASS_LIST_4 BOOST_REMOTE_CALL_CLASS_LIST_3, class A4
|
||||
#define BOOST_REMOTE_CALL_CLASS_LIST_5 BOOST_REMOTE_CALL_CLASS_LIST_4, class A5
|
||||
#define BOOST_REMOTE_CALL_CLASS_LIST_6 BOOST_REMOTE_CALL_CLASS_LIST_5, class A6
|
||||
#define BOOST_REMOTE_CALL_CLASS_LIST_7 BOOST_REMOTE_CALL_CLASS_LIST_6, class A7
|
||||
#define BOOST_REMOTE_CALL_CLASS_LIST_8 BOOST_REMOTE_CALL_CLASS_LIST_7, class A8
|
||||
#define BOOST_REMOTE_CALL_CLASS_LIST_9 BOOST_REMOTE_CALL_CLASS_LIST_8, class A9
|
||||
|
||||
|
||||
#define BOOST_REMOTE_CALL_ARGUMENT_LIST_0
|
||||
#define BOOST_REMOTE_CALL_ARGUMENT_LIST_1 BOOST_REMOTE_CALL_ARGUMENT_LIST_0 A1 oA1
|
||||
#define BOOST_REMOTE_CALL_ARGUMENT_LIST_2 BOOST_REMOTE_CALL_ARGUMENT_LIST_1, A2 oA2
|
||||
#define BOOST_REMOTE_CALL_ARGUMENT_LIST_3 BOOST_REMOTE_CALL_ARGUMENT_LIST_2, A3 oA3
|
||||
#define BOOST_REMOTE_CALL_ARGUMENT_LIST_4 BOOST_REMOTE_CALL_ARGUMENT_LIST_3, A4 oA4
|
||||
#define BOOST_REMOTE_CALL_ARGUMENT_LIST_5 BOOST_REMOTE_CALL_ARGUMENT_LIST_4, A5 oA5
|
||||
#define BOOST_REMOTE_CALL_ARGUMENT_LIST_6 BOOST_REMOTE_CALL_ARGUMENT_LIST_5, A6 oA6
|
||||
#define BOOST_REMOTE_CALL_ARGUMENT_LIST_7 BOOST_REMOTE_CALL_ARGUMENT_LIST_6, A7 oA7
|
||||
#define BOOST_REMOTE_CALL_ARGUMENT_LIST_8 BOOST_REMOTE_CALL_ARGUMENT_LIST_7, A8 oA8
|
||||
#define BOOST_REMOTE_CALL_ARGUMENT_LIST_9 BOOST_REMOTE_CALL_ARGUMENT_LIST_8, A9 oA9
|
||||
|
||||
|
||||
#define BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_0
|
||||
#define BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_1 BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_0, oA1
|
||||
#define BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_2 BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_1, oA2
|
||||
#define BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_3 BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_2, oA3
|
||||
#define BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_4 BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_3, oA4
|
||||
#define BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_5 BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_4, oA5
|
||||
#define BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_6 BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_5, oA6
|
||||
#define BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_7 BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_6, oA7
|
||||
#define BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_8 BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_7, oA8
|
||||
#define BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_9 BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_8, oA9
|
||||
|
||||
|
||||
#define BOOST_REMOTE_CALL_COMMA_0
|
||||
#define BOOST_REMOTE_CALL_COMMA_1 ,
|
||||
#define BOOST_REMOTE_CALL_COMMA_2 ,
|
||||
#define BOOST_REMOTE_CALL_COMMA_3 ,
|
||||
#define BOOST_REMOTE_CALL_COMMA_4 ,
|
||||
#define BOOST_REMOTE_CALL_COMMA_5 ,
|
||||
#define BOOST_REMOTE_CALL_COMMA_6 ,
|
||||
#define BOOST_REMOTE_CALL_COMMA_7 ,
|
||||
#define BOOST_REMOTE_CALL_COMMA_8 ,
|
||||
#define BOOST_REMOTE_CALL_COMMA_9 ,
|
||||
|
||||
|
||||
// this is the macro that ties it all together. From here, we generate all forms of
|
||||
// dt_remote_call and st_remote_call.
|
||||
|
||||
#define BOOST_REMOTE_CALL(context, stack, n) \
|
||||
template<class R BOOST_REMOTE_CALL_CLASS_LIST_ ## n> \
|
||||
inline R context ## _remote_call(stack R (*pfnF)( \
|
||||
BOOST_REMOTE_CALL_ARGUMENT_LIST_ ## n) \
|
||||
BOOST_REMOTE_CALL_COMMA_ ## n \
|
||||
BOOST_REMOTE_CALL_ARGUMENT_LIST_ ## n) \
|
||||
{ \
|
||||
using ::boost::detail::thread::singleton; \
|
||||
using detail::remote_call_manager; \
|
||||
function<R> oFunc(bind(pfnF BOOST_REMOTE_CALL_FUNCTION_ARGUMENT_LIST_ ## n)); \
|
||||
remote_call_manager &rManager(singleton<remote_call_manager>::instance()); \
|
||||
return(rManager.execute_at_ ## context(oFunc)); \
|
||||
}
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
|
||||
BOOST_REMOTE_CALL(st, , 0)
|
||||
BOOST_REMOTE_CALL(st, , 1)
|
||||
BOOST_REMOTE_CALL(st, , 2)
|
||||
BOOST_REMOTE_CALL(st, , 3)
|
||||
BOOST_REMOTE_CALL(st, , 4)
|
||||
BOOST_REMOTE_CALL(st, , 5)
|
||||
BOOST_REMOTE_CALL(st, , 6)
|
||||
BOOST_REMOTE_CALL(st, , 7)
|
||||
BOOST_REMOTE_CALL(st, , 8)
|
||||
BOOST_REMOTE_CALL(st, , 9)
|
||||
|
||||
BOOST_REMOTE_CALL(dt, , 0)
|
||||
BOOST_REMOTE_CALL(dt, , 1)
|
||||
BOOST_REMOTE_CALL(dt, , 2)
|
||||
BOOST_REMOTE_CALL(dt, , 3)
|
||||
BOOST_REMOTE_CALL(dt, , 4)
|
||||
BOOST_REMOTE_CALL(dt, , 5)
|
||||
BOOST_REMOTE_CALL(dt, , 6)
|
||||
BOOST_REMOTE_CALL(dt, , 7)
|
||||
BOOST_REMOTE_CALL(dt, , 8)
|
||||
BOOST_REMOTE_CALL(dt, , 9)
|
||||
|
||||
|
||||
BOOST_REMOTE_CALL(st, pascal, 0)
|
||||
BOOST_REMOTE_CALL(st, pascal, 1)
|
||||
BOOST_REMOTE_CALL(st, pascal, 2)
|
||||
BOOST_REMOTE_CALL(st, pascal, 3)
|
||||
BOOST_REMOTE_CALL(st, pascal, 4)
|
||||
BOOST_REMOTE_CALL(st, pascal, 5)
|
||||
BOOST_REMOTE_CALL(st, pascal, 6)
|
||||
BOOST_REMOTE_CALL(st, pascal, 7)
|
||||
BOOST_REMOTE_CALL(st, pascal, 8)
|
||||
BOOST_REMOTE_CALL(st, pascal, 9)
|
||||
|
||||
BOOST_REMOTE_CALL(dt, pascal, 0)
|
||||
BOOST_REMOTE_CALL(dt, pascal, 1)
|
||||
BOOST_REMOTE_CALL(dt, pascal, 2)
|
||||
BOOST_REMOTE_CALL(dt, pascal, 3)
|
||||
BOOST_REMOTE_CALL(dt, pascal, 4)
|
||||
BOOST_REMOTE_CALL(dt, pascal, 5)
|
||||
BOOST_REMOTE_CALL(dt, pascal, 6)
|
||||
BOOST_REMOTE_CALL(dt, pascal, 7)
|
||||
BOOST_REMOTE_CALL(dt, pascal, 8)
|
||||
BOOST_REMOTE_CALL(dt, pascal, 9)
|
||||
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_REMOTE_CALLS_MJM012402_HPP
|
||||
216
src/mac/safe.cpp
216
src/mac/safe.cpp
@@ -1,216 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#include <DriverServices.h>
|
||||
#include <Events.h>
|
||||
#include <Multiprocessing.h>
|
||||
#include <Threads.h>
|
||||
|
||||
#include <boost/bind.hpp>
|
||||
#include <boost/function.hpp>
|
||||
|
||||
#include <boost/thread/detail/force_cast.hpp>
|
||||
#include <limits>
|
||||
#include "execution_context.hpp"
|
||||
|
||||
|
||||
using boost::detail::thread::force_cast;
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
static OSStatus safe_wait(function<OSStatus, Duration> &rFunction, Duration lDuration);
|
||||
|
||||
|
||||
// we call WNE to allow tasks that own the resource the blue is waiting on system
|
||||
// task time, in case they are blocked on an ST remote call (or a memory allocation
|
||||
// for that matter).
|
||||
static void idle()
|
||||
{
|
||||
if(at_st())
|
||||
{
|
||||
EventRecord sEvent;
|
||||
bool bEvent = WaitNextEvent(0U, &sEvent, 0UL, NULL);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
OSStatus safe_wait_on_semaphore(MPSemaphoreID pSemaphoreID, Duration lDuration)
|
||||
{
|
||||
function<OSStatus, Duration> oWaitOnSemaphore;
|
||||
oWaitOnSemaphore = bind(MPWaitOnSemaphore, pSemaphoreID, _1);
|
||||
return(safe_wait(oWaitOnSemaphore, lDuration));
|
||||
}
|
||||
|
||||
|
||||
OSStatus safe_enter_critical_region(MPCriticalRegionID pCriticalRegionID, Duration lDuration, MPCriticalRegionID pCriticalRegionCriticalRegionID/* = kInvalidID*/)
|
||||
{
|
||||
if(pCriticalRegionCriticalRegionID != kInvalidID)
|
||||
{
|
||||
if(at_mp())
|
||||
{
|
||||
// enter the critical region's critical region
|
||||
OSStatus lStatus = noErr;
|
||||
AbsoluteTime sExpiration;
|
||||
if(lDuration != kDurationImmediate && lDuration != kDurationForever)
|
||||
{
|
||||
sExpiration = AddDurationToAbsolute(lDuration, UpTime());
|
||||
}
|
||||
lStatus = MPEnterCriticalRegion(pCriticalRegionCriticalRegionID, lDuration);
|
||||
assert(lStatus == noErr || lStatus == kMPTimeoutErr);
|
||||
if(lStatus == noErr)
|
||||
{
|
||||
// calculate a new duration
|
||||
if(lDuration != kDurationImmediate && lDuration != kDurationForever)
|
||||
{
|
||||
// check if we have any time left
|
||||
AbsoluteTime sUpTime(UpTime());
|
||||
if(force_cast<uint64_t>(sExpiration) > force_cast<uint64_t>(sUpTime))
|
||||
{
|
||||
// reset our duration to our remaining time
|
||||
lDuration = AbsoluteDeltaToDuration(sExpiration, sUpTime);
|
||||
}
|
||||
else
|
||||
{
|
||||
// no time left
|
||||
lDuration = kDurationImmediate;
|
||||
}
|
||||
}
|
||||
// if we entered the critical region, exit it again
|
||||
lStatus = MPExitCriticalRegion(pCriticalRegionCriticalRegionID);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
else
|
||||
{
|
||||
// otherwise, give up
|
||||
return(lStatus);
|
||||
}
|
||||
}
|
||||
else
|
||||
{
|
||||
// if we're at system task time, try to enter the critical region's critical
|
||||
// region until we succeed. MP tasks will block on this until we let it go.
|
||||
OSStatus lStatus;
|
||||
do
|
||||
{
|
||||
lStatus = MPEnterCriticalRegion(pCriticalRegionCriticalRegionID, kDurationImmediate);
|
||||
} while(lStatus == kMPTimeoutErr);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
}
|
||||
|
||||
// try to enter the critical region
|
||||
function<OSStatus, Duration> oEnterCriticalRegion;
|
||||
oEnterCriticalRegion = bind(MPEnterCriticalRegion, pCriticalRegionID, _1);
|
||||
OSStatus lStatus = safe_wait(oEnterCriticalRegion, lDuration);
|
||||
|
||||
// if we entered the critical region's critical region to get the critical region,
|
||||
// exit the critical region's critical region.
|
||||
if(pCriticalRegionCriticalRegionID != kInvalidID && at_mp() == false)
|
||||
{
|
||||
lStatus = MPExitCriticalRegion(pCriticalRegionCriticalRegionID);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
return(lStatus);
|
||||
}
|
||||
|
||||
OSStatus safe_wait_on_queue(MPQueueID pQueueID, void **pParam1, void **pParam2, void **pParam3, Duration lDuration)
|
||||
{
|
||||
function<OSStatus, Duration> oWaitOnQueue;
|
||||
oWaitOnQueue = bind(MPWaitOnQueue, pQueueID, pParam1, pParam2, pParam3, _1);
|
||||
return(safe_wait(oWaitOnQueue, lDuration));
|
||||
}
|
||||
|
||||
OSStatus safe_delay_until(AbsoluteTime *pWakeUpTime)
|
||||
{
|
||||
if(execution_context() == k_eExecutionContextMPTask)
|
||||
{
|
||||
return(MPDelayUntil(pWakeUpTime));
|
||||
}
|
||||
else
|
||||
{
|
||||
uint64_t ullWakeUpTime = force_cast<uint64_t>(*pWakeUpTime);
|
||||
|
||||
while(force_cast<uint64_t>(UpTime()) < ullWakeUpTime)
|
||||
{
|
||||
idle();
|
||||
}
|
||||
|
||||
return(noErr);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
OSStatus safe_wait(function<OSStatus, Duration> &rFunction, Duration lDuration)
|
||||
{
|
||||
if(execution_context() == k_eExecutionContextMPTask)
|
||||
{
|
||||
return(rFunction(lDuration));
|
||||
}
|
||||
else
|
||||
{
|
||||
uint64_t ullExpiration = 0ULL;
|
||||
|
||||
// get the expiration time in UpTime units
|
||||
if(lDuration == kDurationForever)
|
||||
{
|
||||
ullExpiration = ::std::numeric_limits<uint64_t>::max();
|
||||
}
|
||||
else if(lDuration == kDurationImmediate)
|
||||
{
|
||||
ullExpiration = force_cast<uint64_t>(UpTime());
|
||||
}
|
||||
else
|
||||
{
|
||||
AbsoluteTime sExpiration = AddDurationToAbsolute(lDuration, UpTime());
|
||||
ullExpiration = force_cast<uint64_t>(sExpiration);
|
||||
}
|
||||
|
||||
OSStatus lStatus;
|
||||
bool bExpired = false;
|
||||
|
||||
do
|
||||
{
|
||||
lStatus = rFunction(kDurationImmediate);
|
||||
// mm - "if" #if 0'd out to allow task time to threads blocked on I/O
|
||||
#if 0
|
||||
if(lStatus == kMPTimeoutErr)
|
||||
#endif
|
||||
{
|
||||
idle();
|
||||
}
|
||||
if(lDuration != kDurationForever)
|
||||
{
|
||||
bExpired = (force_cast<uint64_t>(UpTime()) < ullExpiration);
|
||||
}
|
||||
} while(lStatus == kMPTimeoutErr && bExpired == false);
|
||||
|
||||
return(lStatus);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
@@ -1,47 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_SAFE_MJM012402_HPP
|
||||
#define BOOST_SAFE_MJM012402_HPP
|
||||
|
||||
|
||||
#include <Multiprocessing.h>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
// these functions are used to wain in an execution context-independent manor. All of these
|
||||
// functions are both MP- and ST-safe.
|
||||
|
||||
OSStatus safe_wait_on_semaphore(MPSemaphoreID pSemaphoreID, Duration lDuration);
|
||||
OSStatus safe_enter_critical_region(MPCriticalRegionID pCriticalRegionID, Duration lDuration, MPCriticalRegionID pCriticalRegionCriticalRegionID = kInvalidID);
|
||||
OSStatus safe_wait_on_queue(MPQueueID pQueueID, void **pParam1, void **pParam2, void **pParam3, Duration lDuration);
|
||||
OSStatus safe_delay_until(AbsoluteTime *pWakeUpTime);
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
#endif // BOOST_SAFE_MJM012402_HPP
|
||||
@@ -1,53 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#include "scoped_critical_region.hpp"
|
||||
|
||||
#include "init.hpp"
|
||||
|
||||
|
||||
#include <cassert>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
scoped_critical_region::scoped_critical_region():
|
||||
m_pCriticalRegionID(kInvalidID)
|
||||
{
|
||||
static bool bIgnored = thread_init();
|
||||
OSStatus lStatus = MPCreateCriticalRegion(&m_pCriticalRegionID);
|
||||
if(lStatus != noErr || m_pCriticalRegionID == kInvalidID)
|
||||
throw(thread_resource_error());
|
||||
}
|
||||
|
||||
scoped_critical_region::~scoped_critical_region()
|
||||
{
|
||||
OSStatus lStatus = MPDeleteCriticalRegion(m_pCriticalRegionID);
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
@@ -1,69 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_SCOPED_CRITICAL_REGION_MJM012402_HPP
|
||||
#define BOOST_SCOPED_CRITICAL_REGION_MJM012402_HPP
|
||||
|
||||
|
||||
#include <boost/thread/exceptions.hpp>
|
||||
|
||||
#include <Multiprocessing.h>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
// class scoped_critical_region probably needs a new name. Although the current name
|
||||
// is accurate, it can be read to mean that a critical region is entered for the
|
||||
// current scope. In reality, a critical region is _created_ for the current scope.
|
||||
// This class is intended as a replacement for MPCriticalRegionID that will
|
||||
// automatically create and dispose of itself.
|
||||
|
||||
class scoped_critical_region
|
||||
{
|
||||
public:
|
||||
scoped_critical_region();
|
||||
~scoped_critical_region();
|
||||
|
||||
public:
|
||||
operator const MPCriticalRegionID &() const;
|
||||
const MPCriticalRegionID &get() const;
|
||||
|
||||
private:
|
||||
MPCriticalRegionID m_pCriticalRegionID;
|
||||
};
|
||||
|
||||
|
||||
// these are inlined for speed.
|
||||
inline scoped_critical_region::operator const MPCriticalRegionID &() const
|
||||
{ return(m_pCriticalRegionID); }
|
||||
inline const MPCriticalRegionID &scoped_critical_region::get() const
|
||||
{ return(m_pCriticalRegionID); }
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_SCOPED_CRITICAL_REGION_MJM012402_HPP
|
||||
@@ -1,91 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#include "st_scheduler.hpp"
|
||||
|
||||
#include <cassert>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
#if TARGET_CARBON
|
||||
|
||||
st_scheduler::st_scheduler():
|
||||
m_uppTask(NULL),
|
||||
m_pTimer(NULL)
|
||||
{
|
||||
m_uppTask = NewEventLoopTimerUPP(task_entry);
|
||||
// TODO - throw on error
|
||||
assert(m_uppTask != NULL);
|
||||
}
|
||||
|
||||
st_scheduler::~st_scheduler()
|
||||
{
|
||||
DisposeEventLoopTimerUPP(m_uppTask);
|
||||
m_uppTask = NULL;
|
||||
}
|
||||
|
||||
|
||||
void st_scheduler::start_polling()
|
||||
{
|
||||
assert(m_pTimer == NULL);
|
||||
OSStatus lStatus = InstallEventLoopTimer(GetMainEventLoop(),
|
||||
0 * kEventDurationSecond,
|
||||
kEventDurationMillisecond,
|
||||
m_uppTask,
|
||||
this,
|
||||
&m_pTimer);
|
||||
// TODO - throw on error
|
||||
assert(lStatus == noErr);
|
||||
}
|
||||
|
||||
void st_scheduler::stop_polling()
|
||||
{
|
||||
assert(m_pTimer != NULL);
|
||||
OSStatus lStatus = RemoveEventLoopTimer(m_pTimer);
|
||||
assert(lStatus == noErr);
|
||||
m_pTimer = NULL;
|
||||
}
|
||||
|
||||
|
||||
/*static*/ pascal void st_scheduler::task_entry(EventLoopTimerRef /*pTimer*/, void *pRefCon)
|
||||
{
|
||||
st_scheduler *pThis = reinterpret_cast<st_scheduler *>(pRefCon);
|
||||
assert(pThis != NULL);
|
||||
pThis->task();
|
||||
}
|
||||
|
||||
void st_scheduler::task()
|
||||
{
|
||||
periodic_function();
|
||||
}
|
||||
|
||||
#else
|
||||
# error st_scheduler unimplemented!
|
||||
#endif
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
@@ -1,73 +0,0 @@
|
||||
// Copyright (C) 2001
|
||||
// Mac Murrett
|
||||
//
|
||||
// Permission to use, copy, modify, distribute and sell this software
|
||||
// and its documentation for any purpose is hereby granted without fee,
|
||||
// provided that the above copyright notice appear in all copies and
|
||||
// that both that copyright notice and this permission notice appear
|
||||
// in supporting documentation. Mac Murrett makes no representations
|
||||
// about the suitability of this software for any purpose. It is
|
||||
// provided "as is" without express or implied warranty.
|
||||
//
|
||||
// See http://www.boost.org for most recent version including documentation.
|
||||
|
||||
#ifndef BOOST_ST_SCHEDULER_MJM012402_HPP
|
||||
#define BOOST_ST_SCHEDULER_MJM012402_HPP
|
||||
|
||||
|
||||
#include <CarbonEvents.h>
|
||||
|
||||
|
||||
namespace boost {
|
||||
|
||||
namespace threads {
|
||||
|
||||
namespace mac {
|
||||
|
||||
namespace detail {
|
||||
|
||||
|
||||
// class st_scheduler calls its pure-virtual periodic_function method periodically at
|
||||
// system task time. This is generally 40Hz under Mac OS 9.
|
||||
|
||||
class st_scheduler
|
||||
{
|
||||
public:
|
||||
st_scheduler();
|
||||
virtual ~st_scheduler();
|
||||
|
||||
protected:
|
||||
void start_polling();
|
||||
void stop_polling();
|
||||
|
||||
private:
|
||||
virtual void periodic_function() = 0;
|
||||
|
||||
#if TARGET_CARBON
|
||||
// use event loop timers under Carbon
|
||||
private:
|
||||
static pascal void task_entry(EventLoopTimerRef pTimer, void *pRefCon);
|
||||
void task();
|
||||
|
||||
private:
|
||||
EventLoopTimerUPP m_uppTask;
|
||||
EventLoopTimerRef m_pTimer;
|
||||
#else
|
||||
// this can be implemented using OT system tasks. This would be mostly a copy-and-
|
||||
// paste of the dt_scheduler code, replacing DeferredTask with SystemTask and DT
|
||||
// with ST.
|
||||
# error st_scheduler unimplemented!
|
||||
#endif
|
||||
};
|
||||
|
||||
|
||||
} // namespace detail
|
||||
|
||||
} // namespace mac
|
||||
|
||||
} // namespace threads
|
||||
|
||||
} // namespace boost
|
||||
|
||||
|
||||
#endif // BOOST_ST_SCHEDULER_MJM012402_HPP
|
||||
Some files were not shown because too many files have changed in this diff Show More
Reference in New Issue
Block a user