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

/*

 *  (C) 2001 by Argonne National Laboratory.

 *      See COPYRIGHT in top-level directory.

 */

#include <stdio.h>

#include <mpi.h>

#include "mpitest.h"

/* Run with 1 process.

   This program does an MPI_Get with an indexed datatype. The datatype

   comprises a single integer at an initial displacement of 1 integer.

   That is, the first integer in the array is to be skipped.

   This program found a bug in IBM's MPI in which MPI_Get ignored the

   displacement and got the first integer instead of the second.

*/

int main(int argc, char **argv)

{

    int rank, nprocs, mpi_err, *array;

    int getval, disp, errs = 0;

    MPI_Win win;

    MPI_Datatype type;

    MTest_Init(&argc, &argv);

    MPI_Comm_rank(MPI_COMM_WORLD, &rank;;

    MPI_Comm_size(MPI_COMM_WORLD, &nprocs);

    if (rank == 0) {

        /* To improve reporting of problems about operations, we

         * change the error handler to errors return */

        MPI_Comm_set_errhandler(MPI_COMM_SELF, MPI_ERRORS_RETURN);

        /* create an indexed datatype that points to the second integer

         * in an array (the first integer is skipped). */

        disp = 1;

        mpi_err = MPI_Type_create_indexed_block(1, 1, &disp, MPI_INT, &type);

        if (mpi_err != MPI_SUCCESS)

            goto err_return;

        mpi_err = MPI_Type_commit(&type);

        if (mpi_err != MPI_SUCCESS)

            goto err_return;

        /* allocate window of size 2 integers */

        mpi_err = MPI_Alloc_mem(2 * sizeof(int), MPI_INFO_NULL, &array);

        if (mpi_err != MPI_SUCCESS)

            goto err_return;

        /* create window object */

        mpi_err =

            MPI_Win_create(array, 2 * sizeof(int), sizeof(int), MPI_INFO_NULL, MPI_COMM_SELF, &win);

        if (mpi_err != MPI_SUCCESS)

            goto err_return;

        /* initialize array */

        array[0] = 100;

        array[1] = 200;

        getval = 0;

        /* To improve reporting of problems about operations, we

         * change the error handler to errors return */

        MPI_Win_set_errhandler(win, MPI_ERRORS_RETURN);

        mpi_err = MPI_Win_lock(MPI_LOCK_EXCLUSIVE, 0, 0, win);

        if (mpi_err != MPI_SUCCESS)

            goto err_return;

        /* get the current value of element array[1] */

        mpi_err = MPI_Get(&getval, 1, MPI_INT, 0, 0, 1, type, win);

        if (mpi_err != MPI_SUCCESS)

            goto err_return;

        mpi_err = MPI_Win_unlock(0, win);

        if (mpi_err != MPI_SUCCESS)

            goto err_return;

        /* getval should contain the value of array[1] */

        if (getval != array[1]) {

            errs++;

            printf("getval=%d, should be %d\n", getval, array[1]);

        }

        MPI_Free_mem(array);

        MPI_Win_free(&win);

        MPI_Type_free(&type);

    }

    MTest_Finalize(errs);

    MPI_Finalize();

    return 0;

  err_return:

    printf("MPI function error returned an error\n");

    MTestPrintError(mpi_err);

    errs++;

    MTest_Finalize(errs);

    MPI_Finalize();

    return 1;

}