# Copyright 2006 Roland Schwarz.
# Distributed under the Boost Software License, Version 1.0. (See
# accompanying file LICENSE_1_0.txt or copy at
# http://www.boost.org/LICENSE_1_0.txt)
#
# This work is a reimplementation along the design and ideas
# of William E. Kempf.

# find out if pthread is available on current build platform
rule threads::is-pthread-available
{
	if $(OS) = "NT" {
		if $(PTW32_INCLUDE) && $(PTW32_LIB) {
			return true ;
		}
		else {
			ECHO "******************************************************" ;
			ECHO "Building Boost.Thread without pthread support" ;
			ECHO "If you need pthread you should specify the paths." ;
			ECHO "For example:" ;
			ECHO "PTW32_INCLUDE=C:\\Program Files\\ptw32\\Pre-built2\\include" ;
			ECHO "PTW32_LIB=C:\\Program Files\\ptw32\\Pre-built2\\lib\\pthreadVC2.lib" ;
			ECHO "******************************************************" ;
		}
	}
	else if $(OS) = "LINUX" {
		return true ;
	}
	else { ## assume pthread is available on unknown os for now
		return true ;
	}
}

# find the native library variant for current build os
rule threads::is-native-on-build-os ( libvariant )
{
	if      $(OS) = "NT" {
		if $(libvariant) = win32 { return true ; }
	}
	else if $(OS) = "LINUX" {
		if $(libvariant) = pthread { return true ; }
	}
	else { ## assume pthread is native on others for now
		if $(libvariant) = pthread { return true ; }
	}
}

# utility to prepend the source path to the cpp sources
rule threads::cpp_source ( path : sources * )
{
	return $(path)/$(sources).cpp ;
}

# impose the pthread library and include path on the requirements
rule threads::lib-pthread ( toolset variant : subvariant-path properties * )
{
        if $(OS) = "NT" &&  $(PTW32_INCLUDE) && $(PTW32_LIB) {
		properties = [ impose-requirements $(properties) :
                	<define>BOOST_HAS_PTHREADS
			<include>$(PTW32_INCLUDE)
			<library-file>$(PTW32_LIB) ] ;
        }
        
	return $(subvariant-path) $(properties) ;
}