/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil ; -*- */
/*
 *
 *  (C) 2005 by Argonne National Laboratory.
 *      See COPYRIGHT in top-level directory.
 */
#include "mpi.h"
#include <stdio.h>
#include "mpitest.h"

/*
static char MTEST_Descrip[] = "Use Spawn to create an intercomm, then create a new intercomm that includes processes not in the initial spawn intercomm";
*/

/*
 * This test ensures that spawned processes are able to communicate with
 * processes that were not in the communicator from which they were spawned.
 */

int main(int argc, char *argv[])
{
    int errs = 0;
    int wrank, wsize;
    int np = 2;
    int errcodes[2];
    MPI_Comm parentcomm, intercomm, intercomm2;
    int can_spawn;

    MTest_Init(&argc, &argv);

    errs += MTestSpawnPossible(&can_spawn);

    if (can_spawn) {
        MPI_Comm_rank(MPI_COMM_WORLD, &wrank);
        MPI_Comm_size(MPI_COMM_WORLD, &wsize);

        MPI_Comm_get_parent(&parentcomm);

        if (parentcomm == MPI_COMM_NULL) {
            /* Create 2 more processes, from process 0 in the original
             * comm world */
            if (wrank == 0) {
                MPI_Comm_spawn((char *) "./spaiccreate", MPI_ARGV_NULL, np,
                               MPI_INFO_NULL, 0, MPI_COMM_SELF, &intercomm, errcodes);
            } else {
                intercomm = MPI_COMM_NULL;
            }
        } else
            intercomm = parentcomm;

        /* We now have a valid intercomm.  Use it to create a NEW intercomm
         * that includes all processes */
        MPI_Intercomm_create(MPI_COMM_WORLD, 0, intercomm, 0, 123, &intercomm2);

        /* Have the spawned processes send to rank 1 in the comm world of the
         * parent */
        if (parentcomm == MPI_COMM_NULL) {
            MPI_Send(&wrank, 1, MPI_INT, 1, wrank, intercomm2);
        } else {
            if (wrank == 1) {
                int i, rsize, rrank;
                MPI_Status status;

                MPI_Comm_remote_size(intercomm2, &rsize);
                for (i = 0; i < rsize; i++) {
                    MPI_Recv(&rrank, 1, MPI_INT, i, i, intercomm2, &status);
                    if (rrank != i) {
                        errs++;
                        printf("Received %d from %d; expected %d\n", rrank, i, i);
                    }
                }
            }
        }

        /*    printf("%sAbout to barrier on intercomm2\n",
         * (parentcomm == MPI_COMM_NULL) ? "<orig>" : "<spawned>");
         * fflush(stdout); */
        MPI_Barrier(intercomm2);

        /* It isn't necessary to free the intercomms, but it should not hurt */
        if (intercomm != MPI_COMM_NULL)
            MPI_Comm_free(&intercomm);
        MPI_Comm_free(&intercomm2);

        /* Note that the MTest_Finalize get errs only over COMM_WORLD */
        /* Note also that both the parent and child will generate "No Errors"
         * if both call MTest_Finalize */
        if (parentcomm == MPI_COMM_NULL) {
            MTest_Finalize(errs);
        } else {
            MPI_Finalize();
        }
    } else {
        MTest_Finalize(errs);
    }

    return MTestReturnValue(errs);
}
