/* -*- 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"

#include "mpicolltest.h"

/*

static char MTEST_Descrip[] = "Simple intercomm scatter test";

*/

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

{

    int errs = 0, err;

    int *buf = 0;

    int leftGroup, i, count, rank, size, rsize;

    MPI_Comm comm;

    MPI_Datatype datatype;

    MTest_Init(&argc, &argv);

    datatype = MPI_INT;

    /* Get an intercommunicator */

    while (MTestGetIntercomm(&comm, &leftGroup, 4)) {

        if (comm == MPI_COMM_NULL)

            continue;

        MPI_Comm_remote_size(comm, &rsize);

        MPI_Comm_rank(comm, &rank;;

        MPI_Comm_size(comm, &size);

        /* To improve reporting of problems about operations, we

         * change the error handler to errors return */

        MPI_Comm_set_errhandler(comm, MPI_ERRORS_RETURN);

        for (count = 1; count < 65000; count = 2 * count) {

            buf = 0;

            if (leftGroup) {

                buf = (int *) malloc(count * rsize * sizeof(int));

                if (rank == 0) {

                    for (i = 0; i < count * rsize; i++)

                        buf[i] = i;

                } else {

                    for (i = 0; i < count * rsize; i++)

                        buf[i] = -1;

                }

                err = MTest_Scatter(buf, count, datatype,

                                    NULL, 0, datatype,

                                    (rank == 0) ? MPI_ROOT : MPI_PROC_NULL, comm);

                if (err) {

                    errs++;

                    MTestPrintError(err);

                }

                /* Test that no other process in this group received the

                 * scatter */

                if (rank != 0) {

                    for (i = 0; i < count * rsize; i++) {

                        if (buf[i] != -1) {

                            if (errs < 10) {

                                fprintf(stderr, "Received data on root group!\n");

                            }

                            errs++;

                        }

                    }

                }

            } else {

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

                /* In the right group */

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

                    buf[i] = -1;

                err = MTest_Scatter(NULL, 0, datatype, buf, count, datatype, 0, comm);

                if (err) {

                    errs++;

                    MTestPrintError(err);

                }

                /* Check that we have received the correct data */

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

                    if (buf[i] != i + rank * count) {

                        if (errs < 10)

                            fprintf(stderr, "buf[%d] = %d on %d\n", i, buf[i], rank);

                        errs++;

                    }

                }

            }

            free(buf);

        }

        MTestFreeComm(&comm);

    }

    MTest_Finalize(errs);

    return MTestReturnValue(errs);

}