NcMPI.h

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#if !defined(INC_netCDF_NcMPI)
#define INC_netCDF_NcMPI

#ifndef USE_PARALLEL
  #error For parallel netCDF, define USE_PARALLEL during library compilation.
#endif

#ifdef USE_PARALLEL

#include "mpi.h"
#include "NcException.h"
#include <sstream>

namespace netcdf {


    class NcMPI
    {
      public:

        NcMPI ()
          : pComm (0),
            pInfo (0)
          {
          }

        NcMPI (
          MPI::Comm & mpiComm,
          MPI::Info & mpiInfo)
          : pComm (&mpiComm),
            pInfo (&mpiInfo)
          {
            if ( pComm != 0 && !MPI::Is_initialized() )
                NcEXCEPTION( "MPI has not been initialized." );
          }

        NcMPI ( NcMPI const & rhs )
          : pComm (rhs.pComm), pInfo (rhs.pInfo)
          {
          }

        MPI::Comm & Comm () { return *pComm; }
        MPI::Info & Info () { return *pInfo; }

        bool IsInitialized () const
          {
            return pComm != 0 ? MPI::Is_initialized() : false;
          }

        static std::string GetVersion ()
          {
            #if defined(MPICH_VERSION)
                return std::string("MPICH ") + std::string(MPICH_VERSION);
            #elif defined(OMPI_MAJOR_VERSION)
                char const dot = '.';
                std::stringstream os;
                os << "OpenMPI "
                   << OMPI_MAJOR_VERSION << dot << OMPI_MINOR_VERSION << dot << OMPI_RELEASE_VERSION;
                return os.str();
            #else
                std::stringstream os;
                int version = 0, subversion = 0;
                MPI::Get_version( version, subversion );
                os << version << '.' << subversion;
                return os.str();
            #endif
          }

      private:

        MPI::Comm * const pComm;
        MPI::Info * const pInfo;

        // not used
        NcMPI operator= ( NcMPI const & rhs );

    };


} // namespace netcdf

#endif // USE_PARALLEL

#endif // INC_netCDF_NcMPI