allgatherv.c

MPI stands for the Message Passing Interface. Written by the MPI Forum (a large committee comprising

/*
 * Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
 *                         University Research and Technology
 *                         Corporation.  All rights reserved.
 * Copyright (c) 2004-2005 The University of Tennessee and The University
 *                         of Tennessee Research Foundation.  All rights
 *                         reserved.
 * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart, 
 *                         University of Stuttgart.  All rights reserved.
 * Copyright (c) 2004-2005 The Regents of the University of California.
 *                         All rights reserved.
 * $COPYRIGHT$
 * 
 * Additional copyrights may follow
 * 
 * $HEADER$
 */

#include "ompi_config.h"
#include <stdio.h>

#include "ompi/mpi/c/bindings.h"
#include "ompi/datatype/datatype.h"

#if OMPI_HAVE_WEAK_SYMBOLS && OMPI_PROFILING_DEFINES
#pragma weak MPI_Allgatherv = PMPI_Allgatherv
#endif

#if OMPI_PROFILING_DEFINES
#include "ompi/mpi/c/profile/defines.h"
#endif

static const char FUNC_NAME[] = "MPI_Allgatherv";


int MPI_Allgatherv(void *sendbuf, int sendcount, MPI_Datatype sendtype,
                   void *recvbuf, int *recvcounts,
                   int *displs, MPI_Datatype recvtype, MPI_Comm comm) 
{
    int i, size, err;

    if (MPI_PARAM_CHECK) {

        /* Unrooted operation -- same checks for all ranks on both
           intracommunicators and intercommunicators */

        err = MPI_SUCCESS;
        OMPI_ERR_INIT_FINALIZE(FUNC_NAME);
        if (ompi_comm_invalid(comm)) {
            return OMPI_ERRHANDLER_INVOKE(MPI_COMM_WORLD, MPI_ERR_COMM, 
                                          FUNC_NAME);
        } else if (MPI_IN_PLACE == recvbuf) {
          return OMPI_ERRHANDLER_INVOKE(comm, MPI_ERR_ARG, FUNC_NAME);
	}

        if (MPI_IN_PLACE != sendbuf) {
            OMPI_CHECK_DATATYPE_FOR_SEND(err, sendtype, sendcount);
        }
        OMPI_ERRHANDLER_CHECK(err, comm, err, FUNC_NAME);

        size = ompi_comm_size(comm);
        for (i = 0; i < size; ++i) {
          if (recvcounts[i] < 0) {
            return OMPI_ERRHANDLER_INVOKE(comm, MPI_ERR_COUNT, FUNC_NAME);
          } else if (MPI_DATATYPE_NULL == recvtype) {
            return OMPI_ERRHANDLER_INVOKE(comm, MPI_ERR_TYPE, FUNC_NAME);
          }
        }
          
        if (NULL == displs) {
          return OMPI_ERRHANDLER_INVOKE(comm, MPI_ERR_BUFFER, FUNC_NAME);
        }
    }

    /* Do we need to do anything?  Everyone had to give the same 
       signature, which means that everyone must have given a
       sum(recvounts) > 0 if there's anything to do. */

    for (i = 0; i < ompi_comm_size(comm); ++i) {
        if (0 != recvcounts[i]) {
            break;
        }
    }
    if (i >= ompi_comm_size(comm)) {
        return MPI_SUCCESS;
    }

    /* Invoke the coll component to perform the back-end operation */

    err = comm->c_coll.coll_allgatherv(sendbuf, sendcount, sendtype, 
                                       recvbuf, recvcounts, 
                                       displs, recvtype, comm);
    OMPI_ERRHANDLER_RETURN(err, comm, err, FUNC_NAME);
}