/* -*- 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 alltoall test";
*/

int main(int argc, char *argv[])
{
    int errs = 0, err;
    int *sendbuf = 0, *recvbuf = 0;
    int leftGroup, i, j, idx, count, rrank, rsize;
    MPI_Comm comm;
    MPI_Datatype datatype;

    MTest_Init(&argc, &argv);

    datatype = MPI_INT;
    while (MTestGetIntercomm(&comm, &leftGroup, 4)) {
        if (comm == MPI_COMM_NULL)
            continue;
        for (count = 1; count < 66000; count = 2 * count) {
            /* Get an intercommunicator */
            MPI_Comm_remote_size(comm, &rsize);
            MPI_Comm_rank(comm, &rrank);
            sendbuf = (int *) malloc(rsize * count * sizeof(int));
            recvbuf = (int *) malloc(rsize * count * sizeof(int));
            for (i = 0; i < rsize * count; i++)
                recvbuf[i] = -1;
            if (leftGroup) {
                idx = 0;
                for (j = 0; j < rsize; j++) {
                    for (i = 0; i < count; i++) {
                        sendbuf[idx++] = i + rrank;
                    }
                }
                err = MTest_Alltoall(sendbuf, count, datatype, NULL, 0, datatype, comm);
                if (err) {
                    errs++;
                    MTestPrintError(err);
                }
            }
            else {
                int rank, size;

                MPI_Comm_rank(comm, &rank);
                MPI_Comm_size(comm, &size);

                /* In the right group */
                err = MTest_Alltoall(NULL, 0, datatype, recvbuf, count, datatype, comm);
                if (err) {
                    errs++;
                    MTestPrintError(err);
                }
                /* Check that we have received the correct data */
                idx = 0;
                for (j = 0; j < rsize; j++) {
                    for (i = 0; i < count; i++) {
                        if (recvbuf[idx++] != i + j) {
                            errs++;
                            if (errs < 10)
                                fprintf(stderr, "buf[%d] = %d on %d\n", i, recvbuf[i], rank);
                        }
                    }
                }
            }
            free(recvbuf);
            free(sendbuf);
        }
        MTestFreeComm(&comm);
    }

    MTest_Finalize(errs);
    MPI_Finalize();
    return 0;
}
