From 38e585a302e8e5dc144422a11fc901e23dc2f58e Mon Sep 17 00:00:00 2001
From: Douglas Gregor <doug.gregor@gmail.com>
Date: Wed, 29 Aug 2007 16:00:53 +0000
Subject: [PATCH] Constify status::count and status::cancelled. Fixes #1101

[SVN r39052]
---
 include/boost/mpi/communicator.hpp |  6 +++---
 include/boost/mpi/status.hpp       | 12 ++++++------
 src/communicator.cpp               |  2 +-
 3 files changed, 10 insertions(+), 10 deletions(-)

diff --git a/include/boost/mpi/communicator.hpp b/include/boost/mpi/communicator.hpp
index c86684d..2bd8ec9 100644
--- a/include/boost/mpi/communicator.hpp
+++ b/include/boost/mpi/communicator.hpp
@@ -1071,13 +1071,13 @@ inline bool operator!=(const communicator& comm1, const communicator& comm2)
  ************************************************************************/
 // Count elements in a message
 template<typename T> 
-inline optional<int> status::count()
+inline optional<int> status::count() const
 {
   return count_impl<T>(is_mpi_datatype<T>());
 }
 
 template<typename T> 
-optional<int> status::count_impl(mpl::true_)
+optional<int> status::count_impl(mpl::true_) const
 {
   if (m_count != -1)
     return m_count;
@@ -1093,7 +1093,7 @@ optional<int> status::count_impl(mpl::true_)
 }
 
 template<typename T> 
-inline optional<int> status::count_impl(mpl::false_)
+inline optional<int> status::count_impl(mpl::false_) const
 {
   if (m_count == -1)
     return optional<int>();
diff --git a/include/boost/mpi/status.hpp b/include/boost/mpi/status.hpp
index 0bc99dc..734f075 100644
--- a/include/boost/mpi/status.hpp
+++ b/include/boost/mpi/status.hpp
@@ -54,7 +54,7 @@ class BOOST_MPI_DECL status
    * Determine whether the communication associated with this object
    * has been successfully cancelled.
   */
-  bool cancelled();
+  bool cancelled() const;
 
   /**
    * Determines the number of elements of type @c T contained in the
@@ -66,7 +66,7 @@ class BOOST_MPI_DECL status
    * @returns the number of @c T elements in the message, if it can be
    * determined.
    */
-  template<typename T> optional<int> count();
+  template<typename T> optional<int> count() const;
 
   /**
    * References the underlying @c MPI_Status
@@ -82,18 +82,18 @@ class BOOST_MPI_DECL status
   /**
    * INTERNAL ONLY
    */
-  template<typename T> optional<int> count_impl(mpl::true_);
+  template<typename T> optional<int> count_impl(mpl::true_) const;
 
   /**
    * INTERNAL ONLY
    */
-  template<typename T> optional<int> count_impl(mpl::false_);
+  template<typename T> optional<int> count_impl(mpl::false_) const;
 
  public: // friend templates are not portable
 
   /// INTERNAL ONLY
-  MPI_Status m_status;
-  int m_count;
+  mutable MPI_Status m_status;
+  mutable int m_count;
 
   friend class communicator;
   friend class request;
diff --git a/src/communicator.cpp b/src/communicator.cpp
index a93b856..c1e145c 100644
--- a/src/communicator.cpp
+++ b/src/communicator.cpp
@@ -15,7 +15,7 @@ namespace boost { namespace mpi {
 /***************************************************************************
  * status                                                                  *
  ***************************************************************************/
-bool status::cancelled()
+bool status::cancelled() const
 {
   int flag = 0;
   BOOST_MPI_CHECK_RESULT(MPI_Test_cancelled, (&m_status, &flag));