#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <mpi.h>

/*----< main() >------------------------------------------------------------*/
int main(int argc, char **argv) {
    int i, err, rank, nprocs, flag;
    int root_striping_unit, striping_unit, root_striping_factor, striping_factor;
    char value[MPI_MAX_INFO_VAL];
    MPI_File fh;
    MPI_Info info_used;

    MPI_Init(&argc, &argv);
    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
    MPI_Comm_size(MPI_COMM_WORLD, &nprocs);

    if (argc != 2) {
        printf("Usage: %s filename\n",argv[0]);
        MPI_Finalize();
        return 1;
    }
    if (nprocs == 1)
        printf("Warning: this test program is designed for running on more than 1 process\n");

    err = MPI_File_open(MPI_COMM_WORLD, argv[1], MPI_MODE_CREATE | MPI_MODE_RDWR,
                        MPI_INFO_NULL, &fh);
    if (err != MPI_SUCCESS) {
        int errorStringLen;
        char errorString[MPI_MAX_ERROR_STRING];
        MPI_Error_string(err, errorString, &errorStringLen);
        printf("Error: MPI_File_open() %s (%s)\n",argv[1], errorString);
        MPI_Finalize();
        exit(1);
    }
    MPI_File_get_info(fh, &info_used);

    MPI_Info_get(info_used, "striping_unit",   MPI_MAX_INFO_VAL-1, value, &flag);
    striping_unit = atoi(value);
    MPI_Info_get(info_used, "striping_factor", MPI_MAX_INFO_VAL-1, value, &flag);
    striping_factor = atoi(value);

    err = 0;
    root_striping_unit   = striping_unit;
    root_striping_factor = striping_factor;
    MPI_Bcast(&root_striping_unit,  1, MPI_INT, 0, MPI_COMM_WORLD);
    MPI_Bcast(&root_striping_factor, 1, MPI_INT, 0, MPI_COMM_WORLD);
    if (root_striping_unit != striping_unit) {
        printf("Error at PE %2d: inconsistent striping_unit (root=%d local=%d)\n",
               rank, root_striping_unit, striping_unit);
        err++;
    }
    if (root_striping_factor != striping_factor) {
        printf("Error at PE %2d: inconsistent striping_factor (root=%d local=%d)\n",
               rank, root_striping_factor, striping_factor);
        err++;
    }
    if (err == 0 && rank == 0)
        printf("Success: striping_unit=%d striping_factor=%d\n",striping_unit,striping_factor);

    MPI_Info_free(&info_used);
    MPI_File_close(&fh);

    MPI_Finalize();
    return 0;
}