/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */

/*

 *  (C) 2009 by Argonne National Laboratory.

 *      See COPYRIGHT in top-level directory.

 */

/* Based on a test case contributed by Michael Hofmann.

 *

 * This test makes sure that zero counts with non-zero-sized types on the

 * send (recv) side match and don't cause a problem with non-zero counts and

 * zero-sized types on the recv (send) side when using MPI_Alltoallw and

 * MPI_Alltoallv.  */

/* TODO test intercommunicators as well */

#include <stdio.h>

#include <stdlib.h>

#include <mpi.h>

#include "mpitest.h"

int main(int argc, char *argv[])

{

    int sendbuf, recvbuf;

    int *sendcounts;

    int *recvcounts;

    int *sdispls;

    int *rdispls;

    MPI_Datatype sendtype;

    MPI_Datatype *sendtypes;

    MPI_Datatype *recvtypes;

    int rank = -1;

    int size = -1;

    int i;

    MPI_Init(&argc, &argv);

    MPI_Comm_size(MPI_COMM_WORLD, &size);

    MPI_Comm_rank(MPI_COMM_WORLD, &rank;;

    sendtypes = malloc(size * sizeof(MPI_Datatype));

    recvtypes = malloc(size * sizeof(MPI_Datatype));

    sendcounts = malloc(size * sizeof(int));

    recvcounts = malloc(size * sizeof(int));

    sdispls = malloc(size * sizeof(int));

    rdispls = malloc(size * sizeof(int));

    if (!sendtypes || !recvtypes || !sendcounts || !recvcounts || !sdispls || !rdispls) {

        printf("error, unable to allocate memory\n");

        goto fn_exit;

    }

    MPI_Type_contiguous(0, MPI_INT, &sendtype);

    MPI_Type_commit(&sendtype);

    for (i = 0; i < size; ++i) {

        sendtypes[i] = sendtype;

        sendcounts[i] = 1;

        sdispls[i] = 0;

        recvtypes[i] = MPI_INT;

        recvcounts[i] = 0;

        rdispls[i] = 0;

    }

    /* try zero-counts on both the send and recv side in case only one direction is broken for some reason */

    MPI_Alltoallw(&sendbuf, sendcounts, sdispls, sendtypes, &recvbuf, recvcounts, rdispls,

                  recvtypes, MPI_COMM_WORLD);

    MPI_Alltoallw(&sendbuf, recvcounts, rdispls, recvtypes, &recvbuf, sendcounts, sdispls,

                  sendtypes, MPI_COMM_WORLD);

#if MTEST_HAVE_MIN_MPI_VERSION(2,2)

    /* pass MPI_IN_PLACE and different but compatible types rank is even/odd */

    if (rank % 2)

        MPI_Alltoallw(MPI_IN_PLACE, NULL, NULL, NULL, &recvbuf, recvcounts, rdispls, recvtypes,

                      MPI_COMM_WORLD);

    else

        MPI_Alltoallw(MPI_IN_PLACE, NULL, NULL, NULL, &recvbuf, sendcounts, sdispls, sendtypes,

                      MPI_COMM_WORLD);

#endif

    /* now the same for Alltoallv instead of Alltoallw */

    MPI_Alltoallv(&sendbuf, sendcounts, sdispls, sendtypes[0], &recvbuf, recvcounts, rdispls,

                  recvtypes[0], MPI_COMM_WORLD);

    MPI_Alltoallv(&sendbuf, recvcounts, rdispls, recvtypes[0], &recvbuf, sendcounts, sdispls,

                  sendtypes[0], MPI_COMM_WORLD);

#if MTEST_HAVE_MIN_MPI_VERSION(2,2)

    if (rank % 2)

        MPI_Alltoallv(MPI_IN_PLACE, NULL, NULL, MPI_DATATYPE_NULL, &recvbuf, recvcounts, rdispls,

                      recvtypes[0], MPI_COMM_WORLD);

    else

        MPI_Alltoallv(MPI_IN_PLACE, NULL, NULL, MPI_DATATYPE_NULL, &recvbuf, sendcounts, sdispls,

                      sendtypes[0], MPI_COMM_WORLD);

#endif

    MPI_Type_free(&sendtype);

    if (rank == 0)

        printf(" No Errors\n");

  fn_exit:

    if (rdispls)

        free(rdispls);

    if (sdispls)

        free(sdispls);

    if (recvcounts)

        free(recvcounts);

    if (sendcounts)

        free(sendcounts);

    if (recvtypes)

        free(recvtypes);

    if (sendtypes)

        free(sendtypes);

    MPI_Finalize();

    return 0;

}