Edit: /usr/include/boost/mpi/status.hpp (3450B)
// Copyright (C) 2006 Douglas Gregor
.
// Use, modification and distribution is subject to 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)
/** @file status.hpp
*
* This header defines the class @c status, which reports on the
* results of point-to-point communication.
*/
#ifndef BOOST_MPI_STATUS_HPP
#define BOOST_MPI_STATUS_HPP
#include
#include
#include
#include
namespace boost { namespace mpi {
class request;
class communicator;
/** @brief Contains information about a message that has been or can
* be received.
*
* This structure contains status information about messages that
* have been received (with @c communicator::recv) or can be received
* (returned from @c communicator::probe or @c
* communicator::iprobe). It permits access to the source of the
* message, message tag, error code (rarely used), or the number of
* elements that have been transmitted.
*/
class BOOST_MPI_DECL status
{
public:
status() : m_count(-1) { }
status(MPI_Status const& s) : m_status(s), m_count(-1) {}
/**
* Retrieve the source of the message.
*/
int source() const { return m_status.MPI_SOURCE; }
/**
* Retrieve the message tag.
*/
int tag() const { return m_status.MPI_TAG; }
/**
* Retrieve the error code.
*/
int error() const { return m_status.MPI_ERROR; }
/**
* Determine whether the communication associated with this object
* has been successfully cancelled.
*/
bool cancelled() const;
/**
* Determines the number of elements of type @c T contained in the
* message. The type @c T must have an associated data type, i.e.,
* @c is_mpi_datatype must derive @c mpl::true_. In cases where
* the type @c T does not match the transmitted type, this routine
* will return an empty @c optional.
*
* @returns the number of @c T elements in the message, if it can be
* determined.
*/
template optional count() const { return count_impl(is_mpi_datatype()); }
/**
* References the underlying @c MPI_Status
*/
operator MPI_Status&() { return m_status; }
/**
* References the underlying @c MPI_Status
*/
operator const MPI_Status&() const { return m_status; }
private:
/**
* INTERNAL ONLY
*/
template optional count_impl(mpl::true_) const;
/**
* INTERNAL ONLY
*/
template optional count_impl(mpl::false_) const;
public: // friend templates are not portable
/// INTERNAL ONLY
mutable MPI_Status m_status;
mutable int m_count;
friend class communicator;
friend class request;
};
template
inline optional status::count_impl(mpl::true_) const
{
if (m_count != -1)
return m_count;
int return_value;
BOOST_MPI_CHECK_RESULT(MPI_Get_count,
(&m_status, get_mpi_datatype(T()), &return_value));
if (return_value == MPI_UNDEFINED)
return optional();
else
/* Cache the result. */
return m_count = return_value;
}
template
inline optional status::count_impl(mpl::false_) const
{
if (m_count == -1)
return optional();
else
return m_count;
}
} } // end namespace boost::mpi
#endif // BOOST_MPI_STATUS_HPP