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

/*

 *  (C) 2014 by Argonne National Laboratory.

 *      See COPYRIGHT in top-level directory.

 */

#include "mpi.h"

#include <stdio.h>

#include <stdlib.h>

#include "mpitest.h"

/*

static char MTEST_Descrip[] = "Test set_view with DISPLACEMENT_CURRENT";

*/

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

{

    int errs = 0, err;

    int size, rank, *buf;

    MPI_Offset offset;

    MPI_File fh;

    MPI_Comm comm;

    MPI_Status status;

    MPI_Request request;

    MTest_Init(&argc, &argv);

    /* This test reads a header then sets the view to every "size" int,

     * using set view and current displacement.  The file is first written

     * using a combination of collective and ordered writes */

    comm = MPI_COMM_WORLD;

    err = MPI_File_open(comm, (char *) "test.ord",

                        MPI_MODE_WRONLY | MPI_MODE_CREATE, MPI_INFO_NULL, &fh;;

    if (err) {

        errs++;

        MTestPrintErrorMsg("Open(1)", err);

    }

    MPI_Comm_size(comm, &size);

    MPI_Comm_rank(comm, &rank;;

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

    buf[0] = size;

    err = MPI_File_iwrite_all(fh, buf, 1, MPI_INT, &request);

    if (err) {

        errs++;

        MTestPrintErrorMsg("Iwrite_all", err);

    }

    err = MPI_Wait(&request, &status);

    if (err) {

        errs++;

        MTestPrintErrorMsg("Wait", err);

    }

    err = MPI_File_get_position(fh, &offset);

    if (err) {

        errs++;

        MTestPrintErrorMsg("Get_position", err);

    }

    err = MPI_File_seek_shared(fh, offset, MPI_SEEK_SET);

    if (err) {

        errs++;

        MTestPrintErrorMsg("Seek_shared", err);

    }

    buf[0] = rank;

    err = MPI_File_write_ordered(fh, buf, 1, MPI_INT, &status);

    if (err) {

        errs++;

        MTestPrintErrorMsg("Write_ordered", err);

    }

    err = MPI_File_close(&fh;;

    if (err) {

        errs++;

        MTestPrintErrorMsg("Close(1)", err);

    }

    /* Reopen the file as sequential */

    err = MPI_File_open(comm, (char *) "test.ord",

                        MPI_MODE_RDONLY | MPI_MODE_SEQUENTIAL |

                        MPI_MODE_DELETE_ON_CLOSE, MPI_INFO_NULL, &fh;;

    if (err) {

        errs++;

        MTestPrintErrorMsg("Open(Read)", err);

    }

    if (rank == 0) {

        err = MPI_File_read_shared(fh, buf, 1, MPI_INT, &status);

        if (err) {

            errs++;

            MTestPrintErrorMsg("Read_all", err);

        }

        if (buf[0] != size) {

            errs++;

            fprintf(stderr, "Unexpected value for the header = %d, should be %d\n", buf[0], size);

            fflush(stderr);

        }

    }

    MPI_Barrier(comm);

    /* All processes must provide the same file view for MODE_SEQUENTIAL */

    /* See MPI 2.1, 13.3 - DISPLACEMENT_CURRENT is *required* for

     * MODE_SEQUENTIAL files */

    err = MPI_File_set_view(fh, MPI_DISPLACEMENT_CURRENT, MPI_INT,

                            MPI_INT, (char *) "native", MPI_INFO_NULL);

    if (err) {

        errs++;

        MTestPrintErrorMsg("Set_view (DISPLACEMENT_CURRENT)", err);

    }

    buf[0] = -1;

    err = MPI_File_read_ordered(fh, buf, 1, MPI_INT, &status);

    if (err) {

        errs++;

        MTestPrintErrorMsg("Read_all", err);

    }

    if (buf[0] != rank) {

        errs++;

        fprintf(stderr, "%d: buf[0] = %d\n", rank, buf[0]);

        fflush(stderr);

    }

    free(buf);

    err = MPI_File_close(&fh;;

    if (err) {

        errs++;

        MTestPrintErrorMsg("Close(2)", err);

    }

    MTest_Finalize(errs);

    return MTestReturnValue(errs);

}