Chris@16: // Copyright (C) 2006 Douglas Gregor <doug.gregor -at- gmail.com>.
Chris@16: 
Chris@16: // Use, modification and distribution is subject to the Boost Software
Chris@16: // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: // http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: /** @file status.hpp
Chris@16:  *
Chris@16:  *  This header defines the class @c status, which reports on the
Chris@16:  *  results of point-to-point communication.
Chris@16:  */
Chris@16: #ifndef BOOST_MPI_STATUS_HPP
Chris@16: #define BOOST_MPI_STATUS_HPP
Chris@16: 
Chris@16: #include <boost/mpi/config.hpp>
Chris@16: #include <boost/optional.hpp>
Chris@16: 
Chris@16: namespace boost { namespace mpi {
Chris@16: 
Chris@16: class request;
Chris@16: class communicator;
Chris@16: 
Chris@16: /** @brief Contains information about a message that has been or can
Chris@16:  *  be received.
Chris@16:  *
Chris@16:  *  This structure contains status information about messages that
Chris@16:  *  have been received (with @c communicator::recv) or can be received
Chris@16:  *  (returned from @c communicator::probe or @c
Chris@16:  *  communicator::iprobe). It permits access to the source of the
Chris@16:  *  message, message tag, error code (rarely used), or the number of
Chris@16:  *  elements that have been transmitted.
Chris@16:  */
Chris@16: class BOOST_MPI_DECL status
Chris@16: {
Chris@16:  public:
Chris@16:   status() : m_count(-1) { }
Chris@16:   
Chris@16:   status(MPI_Status const& s) : m_status(s), m_count(-1) {}
Chris@16: 
Chris@16:   /**
Chris@16:    * Retrieve the source of the message.
Chris@16:    */
Chris@16:   int source() const { return m_status.MPI_SOURCE; }
Chris@16: 
Chris@16:   /**
Chris@16:    * Retrieve the message tag.
Chris@16:    */
Chris@16:   int tag() const { return m_status.MPI_TAG; }
Chris@16: 
Chris@16:   /**
Chris@16:    * Retrieve the error code.
Chris@16:    */
Chris@16:   int error() const { return m_status.MPI_ERROR; }
Chris@16: 
Chris@16:   /**
Chris@16:    * Determine whether the communication associated with this object
Chris@16:    * has been successfully cancelled.
Chris@16:   */
Chris@16:   bool cancelled() const;
Chris@16: 
Chris@16:   /**
Chris@16:    * Determines the number of elements of type @c T contained in the
Chris@16:    * message. The type @c T must have an associated data type, i.e.,
Chris@16:    * @c is_mpi_datatype<T> must derive @c mpl::true_. In cases where
Chris@16:    * the type @c T does not match the transmitted type, this routine
Chris@16:    * will return an empty @c optional<int>.
Chris@16:    *
Chris@16:    * @returns the number of @c T elements in the message, if it can be
Chris@16:    * determined.
Chris@16:    */
Chris@16:   template<typename T> optional<int> count() const;
Chris@16: 
Chris@16:   /**
Chris@16:    * References the underlying @c MPI_Status
Chris@16:    */
Chris@16:   operator       MPI_Status&()       { return m_status; }
Chris@16: 
Chris@16:   /**
Chris@16:    * References the underlying @c MPI_Status
Chris@16:    */
Chris@16:   operator const MPI_Status&() const { return m_status; }
Chris@16: 
Chris@16:  private:
Chris@16:   /**
Chris@16:    * INTERNAL ONLY
Chris@16:    */
Chris@16:   template<typename T> optional<int> count_impl(mpl::true_) const;
Chris@16: 
Chris@16:   /**
Chris@16:    * INTERNAL ONLY
Chris@16:    */
Chris@16:   template<typename T> optional<int> count_impl(mpl::false_) const;
Chris@16: 
Chris@16:  public: // friend templates are not portable
Chris@16: 
Chris@16:   /// INTERNAL ONLY
Chris@16:   mutable MPI_Status m_status;
Chris@16:   mutable int m_count;
Chris@16: 
Chris@16:   friend class communicator;
Chris@16:   friend class request;
Chris@16: };
Chris@16: 
Chris@16: 
Chris@16: } } // end namespace boost::mpi
Chris@16: 
Chris@16: #endif // BOOST_MPI_STATUS_HPP