/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */

/*

 *

 *  (C) 2001 by Argonne National Laboratory.

 *      See COPYRIGHT in top-level directory.

 */

#include "mpi.h"

#include <stdio.h>

#include <stdlib.h>

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

{

    MPI_Group g1, g2, g4, g5, g45, selfgroup, g6;

    int ranks[16], size, rank, myrank, range[1][3];

    int errs = 0;

    int i, rin[16], rout[16], result;

    MPI_Init(0, 0);

    MPI_Comm_group(MPI_COMM_WORLD, &g1;;

    MPI_Comm_rank(MPI_COMM_WORLD, &myrank);

    MPI_Comm_size(MPI_COMM_WORLD, &size);

    if (size < 8) {

        fprintf(stderr, "Test requires 8 processes (16 prefered) only %d provided\n", size);

        errs++;

    }

    /* 16 members, this process is rank 0, return in group 1 */

    ranks[0] = myrank;

    ranks[1] = 2;

    ranks[2] = 7;

    if (myrank == 2)

        ranks[1] = 3;

    if (myrank == 7)

        ranks[2] = 6;

    MPI_Group_incl(g1, 3, ranks, &g2;;

    /* Check the resulting group */

    MPI_Group_size(g2, &size);

    MPI_Group_rank(g2, &rank;;

    if (size != 3) {

        fprintf(stderr, "Size should be %d, is %d\n", 3, size);

        errs++;

    }

    if (rank != 0) {

        fprintf(stderr, "Rank should be %d, is %d\n", 0, rank);

        errs++;

    }

    rin[0] = 0;

    rin[1] = 1;

    rin[2] = 2;

    MPI_Group_translate_ranks(g2, 3, rin, g1, rout);

    for (i = 0; i < 3; i++) {

        if (rout[i] != ranks[i]) {

            fprintf(stderr, "translated rank[%d] %d should be %d\n", i, rout[i], ranks[i]);

            errs++;

        }

    }

    /* Translate the process of the self group against another group */

    MPI_Comm_group(MPI_COMM_SELF, &selfgroup);

    rin[0] = 0;

    MPI_Group_translate_ranks(selfgroup, 1, rin, g1, rout);

    if (rout[0] != myrank) {

        fprintf(stderr, "translated of self is %d should be %d\n", rout[0], myrank);

        errs++;

    }

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

        rin[i] = i;

    MPI_Group_translate_ranks(g1, size, rin, selfgroup, rout);

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

        if (i == myrank && rout[i] != 0) {

            fprintf(stderr, "translated world to self of %d is %d\n", i, rout[i]);

            errs++;

        }

        else if (i != myrank && rout[i] != MPI_UNDEFINED) {

            fprintf(stderr, "translated world to self of %d should be undefined, is %d\n",

                    i, rout[i]);

            errs++;

        }

    }

    MPI_Group_free(&selfgroup);

    /* Exclude everyone in our group */

    {

        int ii, *lranks, g1size;

        MPI_Group_size(g1, &g1size);

        lranks = (int *) malloc(g1size * sizeof(int));

        for (ii = 0; ii < g1size; ii++)

            lranks[ii] = ii;

        MPI_Group_excl(g1, g1size, lranks, &g6;;

        if (g6 != MPI_GROUP_EMPTY) {

            fprintf(stderr, "Group formed by excluding all ranks not empty\n");

            errs++;

            MPI_Group_free(&g6;;

        }

        free(lranks);

    }

    /* Add tests for additional group operations */

    /*

     * g2 = incl 1,3,7

     * g3 = excl 1,3,7

     * intersect (w, g2) => g2

     * intersect (w, g3) => g3

     * intersect (g2, g3) => empty

     *

     * g4 = rincl 1:n-1:2

     * g5 = rexcl 1:n-1:2

     * union(g4, g5) => world

     * g6 = rincl n-1:1:-1

     * g7 = rexcl n-1:1:-1

     * union(g6, g7) => concat of entries, similar to world

     * diff(w, g2) => g3

     */

    MPI_Group_free(&g2;;

    range[0][0] = 1;

    range[0][1] = size - 1;

    range[0][2] = 2;

    MPI_Group_range_excl(g1, 1, range, &g5;;

    range[0][0] = 1;

    range[0][1] = size - 1;

    range[0][2] = 2;

    MPI_Group_range_incl(g1, 1, range, &g4;;

    MPI_Group_union(g4, g5, &g45);

    MPI_Group_compare(MPI_GROUP_EMPTY, g4, &result);

    if (result != MPI_UNEQUAL) {

        errs++;

        fprintf(stderr, "Comparison with empty group gave %d, not 3\n", result);

    }

    MPI_Group_free(&g4;;

    MPI_Group_free(&g5;;

    MPI_Group_free(&g45);

    /* Now, duplicate the test, but using negative strides */

    range[0][0] = size - 1;

    range[0][1] = 1;

    range[0][2] = -2;

    MPI_Group_range_excl(g1, 1, range, &g5;;

    range[0][0] = size - 1;

    range[0][1] = 1;

    range[0][2] = -2;

    MPI_Group_range_incl(g1, 1, range, &g4;;

    MPI_Group_union(g4, g5, &g45);

    MPI_Group_compare(MPI_GROUP_EMPTY, g4, &result);

    if (result != MPI_UNEQUAL) {

        errs++;

        fprintf(stderr,

                "Comparison with empty group (formed with negative strides) gave %d, not 3\n",

                result);

    }

    MPI_Group_free(&g4;;

    MPI_Group_free(&g5;;

    MPI_Group_free(&g45);

    MPI_Group_free(&g1;;

    if (myrank == 0) {

        if (errs == 0) {

            printf(" No Errors\n");

        }

        else {

            printf("Found %d errors\n", errs);

        }

    }

    MPI_Finalize();

    return 0;

}