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

/*

 *

 *  (C) 2006 by Argonne National Laboratory.

 *      See COPYRIGHT in top-level directory.

 */

#include "mpi.h"

#include <stdio.h>

#include <stdlib.h>

#include "mpitest.h"

#include "mpithreadtest.h"

/*

static char MTEST_Descrip[] = "Creating communications concurrently in different threads";

*/

MTEST_THREAD_RETURN_TYPE dup_thread(void *);

MTEST_THREAD_RETURN_TYPE dup_thread(void *p)

{

    int rank;

    int buffer[1];

    MPI_Comm *comm2_ptr = (MPI_Comm *) p;

    MPI_Comm comm3;

    MPI_Comm_rank(MPI_COMM_WORLD, &rank;;

    if (rank & 0x1) {

        /* If odd, wait for message */

        MPI_Recv(buffer, 0, MPI_INT, rank, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);

    }

    MPI_Comm_dup(*comm2_ptr, &comm3;;

    MPI_Barrier(comm3);

    MPI_Recv(buffer, 0, MPI_INT, rank, 1, MPI_COMM_WORLD, MPI_STATUS_IGNORE);

    MPI_Comm_free(&comm3;;

    /* Tell the main thread that we're done */

    MPI_Send(buffer, 0, MPI_INT, rank, 2, MPI_COMM_WORLD);

    return (MTEST_THREAD_RETURN_TYPE) 0;

}

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

{

    int rank, size;

    int provided;

    int buffer[1];

    MPI_Comm comm1, comm2, comm4;

    MTest_Init_thread(&argc, &argv, MPI_THREAD_MULTIPLE, &provided);

    MPI_Comm_rank(MPI_COMM_WORLD, &rank;;

    MPI_Comm_size(MPI_COMM_WORLD, &size);

    /* Check that we're multi-threaded */

    if (provided != MPI_THREAD_MULTIPLE) {

        if (rank == 0) {

            printf

                ("MPI_Init_thread must return MPI_THREAD_MULTIPLE in order for this test to run.\n");

            fflush(stdout);

        }

        return 1;

    }

    /* The test is this:

     * The main thread on ODD processors tells the other thread to start

     * a comm dup(on comm2), then starts a comm dup(on comm1) after a delay.

     * The main thread on even processors starts a comm dup(on comm1)

     *

     * The second thread on ODD processors waits until it gets a message

     * (from the same process) before starting the comm dup on comm2.

     */

    /* Create two communicators */

    MPI_Comm_dup(MPI_COMM_WORLD, &comm1;;

    MPI_Comm_dup(MPI_COMM_WORLD, &comm2;;

    /* Start a thread that will perform a dup comm2 */

    MTest_Start_thread(dup_thread, (void *) &comm2;;

    /* If we're odd, send to our new thread and then delay */

    if (rank & 0x1) {

        MPI_Ssend(buffer, 0, MPI_INT, rank, 0, MPI_COMM_WORLD);

        MTestSleep(1);

    }

    MPI_Comm_dup(comm1, &comm4;;

    /* Tell the threads to exit after we've created our new comm */

    MPI_Barrier(comm4);

    MPI_Ssend(buffer, 0, MPI_INT, rank, 1, MPI_COMM_WORLD);

    MPI_Recv(buffer, 0, MPI_INT, rank, 2, MPI_COMM_WORLD, MPI_STATUS_IGNORE);

    MTest_Join_threads();

    MPI_Comm_free(&comm4;;

    MPI_Comm_free(&comm1;;

    MPI_Comm_free(&comm2;;

    MTest_Finalize(0);

    return 0;

}