/*
 * Copyright (C) by Argonne National Laboratory
 *     See COPYRIGHT in top-level directory
 */

#include "mpi.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "mpitest.h"

/*
 * This check is intended to fail if there is a leak of context ids.
 * Because this is trying to exhaust the number of context ids, it needs
 * to run for a longer time than many tests.  The for loop uses 100,000
 * iterations, which is adequate for MPICH (with only about 1k context ids
 * available).
 */

int main(int argc, char **argv)
{

    int i = 0;
    int randval;
    int rank;
    int errs = 0;
    MPI_Comm newcomm;
    double startTime;
    int nLoop = 100000;

    MTest_Init(&argc, &argv);

    for (i = 1; i < argc; i++) {
        if (strcmp(argv[i], "--loopcount") == 0) {
            i++;
            nLoop = atoi(argv[i]);
        } else {
            fprintf(stderr, "Unrecognized argument %s\n", argv[i]);
        }
    }

    MPI_Comm_rank(MPI_COMM_WORLD, &rank);

    startTime = MPI_Wtime();
    for (i = 0; i < nLoop; i++) {

        if (rank == 0 && (i % 100 == 0)) {
            double rate = MPI_Wtime() - startTime;
            if (rate > 0) {
                rate = i / rate;
                MTestPrintfMsg(10, "After %d (%f)\n", i, rate);
            } else {
                MTestPrintfMsg(10, "After %d\n", i);
            }
        }

        /* FIXME: Explain the rationale behind rand in this test */
        randval = rand();

        if (randval % (rank + 2) == 0) {
            MPI_Comm_split(MPI_COMM_WORLD, 1, rank, &newcomm);
            MPI_Comm_free(&newcomm);
        } else {
            MPI_Comm_split(MPI_COMM_WORLD, MPI_UNDEFINED, rank, &newcomm);
            if (newcomm != MPI_COMM_NULL) {
                errs++;
                printf("Created a non-null communicator with MPI_UNDEFINED\n");
            }
        }
    }

    MTest_Finalize(errs);

    return MTestReturnValue(errs);
}
