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

/*

 *

 *  (C) 2003 by Argonne National Laboratory.

 *      See COPYRIGHT in top-level directory.

 */

#include "mpi.h"

#include <stdio.h>

#include <stdlib.h>

#include "mpitest.h"

/*

static char MTEST_Descrip[] = "Test that communicators have reference count semantics";

*/

#define NELM 128

#define NCOMM 1020

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

{

    int errs = 0;

    int rank, size, source, dest, i;

    MPI_Comm comm;

    MPI_Comm tmpComm[NCOMM];

    MPI_Status status;

    MPI_Request req;

    int *buf = 0;

    MTest_Init(&argc, &argv);

    MPI_Comm_dup(MPI_COMM_WORLD, &comm);

    /* This is similar to the datatype test, except that we post

     * an irecv on a simple data buffer but use a rank-reordered communicator.

     * In this case, an error in handling the reference count will most

     * likely cause the program to hang, so this should be run only

     * if (a) you are confident that the code is correct or (b)

     * a timeout is set for mpiexec

     */

    MPI_Comm_rank(comm, &rank;;

    MPI_Comm_size(comm, &size);

    if (size < 2) {

        fprintf(stderr, "This test requires at least two processes.");

        MPI_Abort(MPI_COMM_WORLD, 1);

    }

    source = 0;

    dest = size - 1;

    if (rank == dest) {

        buf = (int *) malloc(NELM * sizeof(int));

        for (i = 0; i < NELM; i++)

            buf[i] = -i;

        MPI_Irecv(buf, NELM, MPI_INT, source, 0, comm, &req;;

        MPI_Comm_free(&comm);

        if (comm != MPI_COMM_NULL) {

            errs++;

            printf("Freed comm was not set to COMM_NULL\n");

        }

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

            MPI_Comm_split(MPI_COMM_WORLD, 0, size - rank, &tmpComm[i]);

        }

        MPI_Sendrecv(NULL, 0, MPI_INT, source, 1,

                     NULL, 0, MPI_INT, source, 1, MPI_COMM_WORLD, &status);

        MPI_Wait(&req, &status);

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

            if (buf[i] != i) {

                errs++;

                if (errs < 10) {

                    printf("buf[%d] = %d, expected %d\n", i, buf[i], i);

                }

            }

        }

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

            MPI_Comm_free(&tmpComm[i]);

        }

        free(buf);

    }

    else if (rank == source) {

        buf = (int *) malloc(NELM * sizeof(int));

        for (i = 0; i < NELM; i++)

            buf[i] = i;

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

            MPI_Comm_split(MPI_COMM_WORLD, 0, size - rank, &tmpComm[i]);

        }

        /* Synchronize with the receiver */

        MPI_Sendrecv(NULL, 0, MPI_INT, dest, 1, NULL, 0, MPI_INT, dest, 1, MPI_COMM_WORLD, &status);

        MPI_Send(buf, NELM, MPI_INT, dest, 0, comm);

        free(buf);

    }

    else {

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

            MPI_Comm_split(MPI_COMM_WORLD, 0, size - rank, &tmpComm[i]);

        }

    }

    MPI_Barrier(MPI_COMM_WORLD);

    if (rank != dest) {

        /* Clean up the communicators */

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

            MPI_Comm_free(&tmpComm[i]);

        }

    }

    if (comm != MPI_COMM_NULL) {

        MPI_Comm_free(&comm);

    }

    MTest_Finalize(errs);

    MPI_Finalize();

    return 0;

}