netcdf-c/libdispatch/dparallel.c
2015-08-15 16:26:35 -06:00

130 lines
2.9 KiB
C

/** \file
This file has the parallel I/O functions.
Copyright 2010 University Corporation for Atmospheric
Research/Unidata. See COPYRIGHT file for more info.
*/
#include "config.h"
#include "ncdispatch.h"
/* This function creates a file for use with parallel I/O. */
int
nc_create_par(const char *path, int cmode, MPI_Comm comm,
MPI_Info info, int *ncidp)
{
#ifndef USE_PARALLEL
return NC_ENOPAR;
#else
NC_MPI_INFO data;
/* One of these two parallel IO modes must be chosen by the user,
* or else pnetcdf must be in use. */
if (!(cmode & NC_MPIIO || cmode & NC_MPIPOSIX) &&
!(cmode & NC_PNETCDF))
return NC_EINVAL;
data.comm = comm;
data.info = info;
return NC_create(path, cmode, 0, 0, NULL, 1, &data, ncidp);
#endif /* USE_PARALLEL */
}
/* This function opens a file for parallel I/O. */
int
nc_open_par(const char *path, int mode, MPI_Comm comm,
MPI_Info info, int *ncidp)
{
#ifndef USE_PARALLEL
return NC_ENOPAR;
#else
NC_MPI_INFO mpi_data;
/* One of these two parallel IO modes must be chosen by the user,
* or else pnetcdf must be in use. */
if ((mode & NC_MPIIO) || (mode & NC_MPIPOSIX)) {
/* ok */
} else if(mode & NC_PNETCDF) {
/* ok */
} else
return NC_EINVAL;
mpi_data.comm = comm;
mpi_data.info = info;
return NC_open(path, mode, 0, NULL, 1, &mpi_data, ncidp);
#endif /* USE_PARALLEL */
}
/* Fortran needs to pass MPI comm/info as integers. */
int
nc_open_par_fortran(const char *path, int mode, int comm,
int info, int *ncidp)
{
#ifndef USE_PARALLEL
return NC_ENOPAR;
#else
MPI_Comm comm_c;
MPI_Info info_c;
/* Convert fortran comm and info to C comm and info, if there is a
* function to do so. Otherwise just pass them. */
#ifdef HAVE_MPI_COMM_F2C
comm_c = MPI_Comm_f2c(comm);
info_c = MPI_Info_f2c(info);
#else
comm_c = (MPI_Comm)comm;
info_c = (MPI_Info)info;
#endif
return nc_open_par(path, mode, comm_c, info_c, ncidp);
#endif
}
/* This function will change the parallel access of a variable from
* independent to collective. */
int
nc_var_par_access(int ncid, int varid, int par_access)
{
NC* ncp;
int stat = NC_NOERR;
if ((stat = NC_check_id(ncid, &ncp)))
return stat;
#ifndef USE_PARALLEL
return NC_ENOPAR;
#else
return ncp->dispatch->var_par_access(ncid,varid,par_access);
#endif
}
/* when calling from fortran: convert MPI_Comm and MPI_Info to C */
int
nc_create_par_fortran(const char *path, int cmode, int comm,
int info, int *ncidp)
{
#ifndef USE_PARALLEL
return NC_ENOPAR;
#else
MPI_Comm comm_c;
MPI_Info info_c;
/* Convert fortran comm and info to C comm and info, if there is a
* function to do so. Otherwise just pass them. */
#ifdef HAVE_MPI_COMM_F2C
comm_c = MPI_Comm_f2c(comm);
info_c = MPI_Info_f2c(info);
#else
comm_c = (MPI_Comm)comm;
info_c = (MPI_Info)info;
#endif
return nc_create_par(path, cmode, comm_c, info_c, ncidp);
#endif
}