/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */
/*
 *  (C) 2007 by Argonne National Laboratory.
 *      See COPYRIGHT in top-level directory.
 */
#include <stdio.h>
#include <stdlib.h>
#include <mpi.h>
#include "mpitest.h"

/* Test that comm_split fails gracefully when the number of communicators
   is exhausted.  Original version submitted by Paul Sack.
*/
#define MAX_COMMS 2000

/* Define VERBOSE to get an output line for every communicator */
/* #define VERBOSE 1 */
int main(int argc, char *argv[])
{
    int i, rank;
    int rc, maxcomm;
    int errs = 0;
    MPI_Comm comm[MAX_COMMS];

    MTest_Init(&argc, &argv);
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
    MPI_Errhandler_set(MPI_COMM_WORLD, MPI_ERRORS_RETURN);

    maxcomm = -1;
    for (i = 0; i < MAX_COMMS; i++) {
#ifdef VERBOSE
        if (rank == 0) {
            if (i % 20 == 0) {
                fprintf(stderr, "\n %d: ", i);
                fflush(stdout);
            }
            else {
                fprintf(stderr, ".");
                fflush(stdout);
            }
        }
#endif
        rc = MPI_Comm_split(MPI_COMM_WORLD, 1, rank, &comm[i]);
        if (rc != MPI_SUCCESS) {
            break;
        }
        maxcomm = i;
    }
    for (i = 0; i <= maxcomm; i++) {
        MPI_Comm_free(&comm[i]);
    }
    /* If we complete, there are no errors */
    MTest_Finalize(errs);
    MPI_Finalize();
    return 0;
}
