/* -*- 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"

/*

 * This test ensures that shrink works correctly

 */

int main(int argc, char **argv)

{

    int rank, size, newsize, rc, errclass, errs = 0;

    MPI_Comm newcomm;

    MPI_Init(&argc, &argv);

    MPI_Comm_rank(MPI_COMM_WORLD, &rank;;

    MPI_Comm_size(MPI_COMM_WORLD, &size);

    MPI_Comm_set_errhandler(MPI_COMM_WORLD, MPI_ERRORS_RETURN);

    if (size < 4) {

        fprintf(stderr, "Must run with at least 4 processes\n");

        MPI_Abort(MPI_COMM_WORLD, 1);

    }

    if (2 == rank)

        exit(EXIT_FAILURE);

    rc = MPIX_Comm_shrink(MPI_COMM_WORLD, &newcomm);

    if (rc) {

        MPI_Error_class(rc, &errclass);

        fprintf(stderr, "Expected MPI_SUCCESS from MPIX_Comm_shrink. Received: %d\n", errclass);

        errs++;

        MPI_Abort(MPI_COMM_WORLD, 1);

    }

    MPI_Comm_size(newcomm, &newsize);

    if (newsize != size - 1)

        errs++;

    rc = MPI_Barrier(newcomm);

    if (rc) {

        MPI_Error_class(rc, &errclass);

        fprintf(stderr, "Expected MPI_SUCCESS from MPI_BARRIER. Received: %d\n", errclass);

        errs++;

        MPI_Abort(MPI_COMM_WORLD, 1);

    }

    MPI_Comm_free(&newcomm);

    if (0 == rank)

        fprintf(stdout, " No Errors\n");

    MPI_Finalize();

    return MTestReturnValue(errs);

}