/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * All rights reserved.                                                      *
 *                                                                           *
 * This file is part of HDF5.  The full HDF5 copyright notice, including     *
 * terms governing use, modification, and redistribution, is contained in    *
 * the LICENSE file, which can be found at the root of the source code       *
 * distribution tree, or in https://www.hdfgroup.org/licenses.               *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#include "testphdf5.h"
#include "H5Dprivate.h"
#include "H5private.h"

#define DIM         2
#define SIZE        32
#define NDATASET    4
#define GROUP_DEPTH 128
enum obj_type { is_group, is_dset };

static int  get_size(void);
static void write_dataset(hid_t, hid_t, hid_t);
static int  read_dataset(hid_t, hid_t, hid_t);
static void create_group_recursive(hid_t, hid_t, hid_t, int);
static void recursive_read_group(hid_t, hid_t, hid_t, int);
static void group_dataset_read(hid_t fid, int mpi_rank, int m);
static void write_attribute(hid_t, int, int);
static int  read_attribute(hid_t, int, int);
static int  check_value(DATATYPE *, DATATYPE *, int);
static void get_slab(hsize_t[], hsize_t[], hsize_t[], hsize_t[], int);

static void rr_obj_hdr_flush_confusion_writer(const void *params, MPI_Comm comm);
static void rr_obj_hdr_flush_confusion_reader(const void *params, MPI_Comm comm);

/*
 * The size value computed by this function is used extensively in
 * configuring tests for the current number of processes.
 *
 * This function was created as part of an effort to allow the
 * test functions in this file to run on an arbitrary number of
 * processors.
 *                                       JRM - 8/11/04
 */

static int
get_size(void)
{
    int mpi_rank;
    int mpi_size;
    int size = SIZE;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank); /* needed for VRFY */
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    if (mpi_size > size) {
        if ((mpi_size % 2) == 0) {
            size = mpi_size;
        }
        else {
            size = mpi_size + 1;
        }
    }

    VRFY((mpi_size <= size), "mpi_size <= size");
    VRFY(((size % 2) == 0), "size isn't even");

    return (size);

} /* get_size() */

/*
 * Example of using PHDF5 to create a zero sized dataset.
 *
 */
void
zero_dim_dset(void *params)
{
    int         mpi_size, mpi_rank;
    const char *filename;
    hid_t       fid, plist, dcpl, dsid, sid;
    hsize_t     dim, chunk_dim;
    herr_t      ret;
    int         data[1];

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf("    API functions for basic file or dataset aren't supported with this connector\n");
            fflush(stdout);
        }

        return;
    }

    filename = ((const H5Ptest_param_t *)params)->name;

    plist = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    VRFY((plist >= 0), "create_faccess_plist succeeded");

    fid = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, plist);
    VRFY((fid >= 0), "H5Fcreate succeeded");
    ret = H5Pclose(plist);
    VRFY((ret >= 0), "H5Pclose succeeded");

    dcpl = H5Pcreate(H5P_DATASET_CREATE);
    VRFY((dcpl >= 0), "failed H5Pcreate");

    /* Set 1 chunk size */
    chunk_dim = 1;
    ret       = H5Pset_chunk(dcpl, 1, &chunk_dim);
    VRFY((ret >= 0), "failed H5Pset_chunk");

    /* Create 1D dataspace with 0 dim size */
    dim = 0;
    sid = H5Screate_simple(1, &dim, NULL);
    VRFY((sid >= 0), "failed H5Screate_simple");

    /* Create chunked dataset */
    dsid = H5Dcreate2(fid, "dset", H5T_NATIVE_INT, sid, H5P_DEFAULT, dcpl, H5P_DEFAULT);
    VRFY((dsid >= 0), "failed H5Dcreate2");

    /* write 0 elements from dataset */
    ret = H5Dwrite(dsid, H5T_NATIVE_INT, sid, sid, H5P_DEFAULT, data);
    VRFY((ret >= 0), "failed H5Dwrite");

    /* Read 0 elements from dataset */
    ret = H5Dread(dsid, H5T_NATIVE_INT, sid, sid, H5P_DEFAULT, data);
    VRFY((ret >= 0), "failed H5Dread");

    H5Pclose(dcpl);
    H5Dclose(dsid);
    H5Sclose(sid);
    H5Fclose(fid);
}

/*
 * Example of using PHDF5 to create ndatasets datasets.  Each process write
 * a slab of array to the file.
 */
void
multiple_dset_write(void *params)
{
    int                    i, j, n, mpi_size, mpi_rank, size;
    hid_t                  iof, plist, dataset, memspace, filespace;
    hid_t                  dcpl; /* Dataset creation property list */
    hsize_t                chunk_origin[DIM];
    hsize_t                chunk_dims[DIM], file_dims[DIM];
    hsize_t                count[DIM] = {1, 1};
    double                *outme      = NULL;
    double                 fill       = 1.0; /* Fill value */
    char                   dname[100];
    herr_t                 ret;
    const H5Ptest_param_t *pt;
    char                  *filename;
    int                    ndatasets;

    pt        = params;
    filename  = pt->name;
    ndatasets = pt->count;

    size = get_size();
    H5_CHECK_OVERFLOW(size, int, size_t);

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf("    API functions for basic file or dataset aren't supported with this connector\n");
            fflush(stdout);
        }

        return;
    }

    outme = malloc((size_t)size * (size_t)size * sizeof(double));
    VRFY((outme != NULL), "malloc succeeded for outme");

    plist = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    VRFY((plist >= 0), "create_faccess_plist succeeded");
    iof = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, plist);
    VRFY((iof >= 0), "H5Fcreate succeeded");
    ret = H5Pclose(plist);
    VRFY((ret >= 0), "H5Pclose succeeded");

    /* decide the hyperslab according to process number. */
    get_slab(chunk_origin, chunk_dims, count, file_dims, size);

    memspace  = H5Screate_simple(DIM, chunk_dims, NULL);
    filespace = H5Screate_simple(DIM, file_dims, NULL);
    ret       = H5Sselect_hyperslab(filespace, H5S_SELECT_SET, chunk_origin, chunk_dims, count, chunk_dims);
    VRFY((ret >= 0), "mdata hyperslab selection");

    /* Create a dataset creation property list */
    dcpl = H5Pcreate(H5P_DATASET_CREATE);
    VRFY((dcpl >= 0), "dataset creation property list succeeded");

    ret = H5Pset_fill_value(dcpl, H5T_NATIVE_DOUBLE, &fill);
    VRFY((ret >= 0), "set fill-value succeeded");

    for (n = 0; n < ndatasets; n++) {
        snprintf(dname, sizeof(dname), "dataset %d", n);
        dataset = H5Dcreate2(iof, dname, H5T_NATIVE_DOUBLE, filespace, H5P_DEFAULT, dcpl, H5P_DEFAULT);
        VRFY((dataset > 0), dname);

        /* calculate data to write */
        for (i = 0; i < size; i++)
            for (j = 0; j < size; j++)
                outme[(i * size) + j] = n * 1000 + mpi_rank;

        H5Dwrite(dataset, H5T_NATIVE_DOUBLE, memspace, filespace, H5P_DEFAULT, outme);

        H5Dclose(dataset);
#ifdef BARRIER_CHECKS
        if (!((n + 1) % 10)) {
            printf("created %d datasets\n", n + 1);
            MPI_Barrier(MPI_COMM_WORLD);
        }
#endif /* BARRIER_CHECKS */
    }

    H5Sclose(filespace);
    H5Sclose(memspace);
    H5Pclose(dcpl);
    H5Fclose(iof);

    free(outme);
}

/* Example of using PHDF5 to create, write, and read compact dataset.
 */
void
compact_dataset(void *params)
{
    int         i, j, mpi_size, mpi_rank, size, err_num = 0;
    hid_t       iof, plist, dcpl, dxpl, dataset, filespace;
    hsize_t     file_dims[DIM];
    double     *outme;
    double     *inme;
    char        dname[] = "dataset";
    herr_t      ret;
    const char *filename;
#ifdef H5_HAVE_INSTRUMENTED_LIBRARY
    bool prop_value;
#endif

    size = get_size();

    for (i = 0; i < DIM; i++)
        file_dims[i] = (hsize_t)size;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf("    API functions for basic file or dataset aren't supported with this connector\n");
            fflush(stdout);
        }

        return;
    }

    outme = malloc((size_t)((size_t)size * (size_t)size * sizeof(double)));
    VRFY((outme != NULL), "malloc succeeded for outme");

    inme = malloc((size_t)size * (size_t)size * sizeof(double));
    VRFY((outme != NULL), "malloc succeeded for inme");

    filename = ((const H5Ptest_param_t *)params)->name;
    VRFY((mpi_size <= size), "mpi_size <= size");

    plist = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    iof   = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, plist);

    /* Define data space */
    filespace = H5Screate_simple(DIM, file_dims, NULL);

    /* Create a compact dataset */
    dcpl = H5Pcreate(H5P_DATASET_CREATE);
    VRFY((dcpl >= 0), "dataset creation property list succeeded");
    ret = H5Pset_layout(dcpl, H5D_COMPACT);
    VRFY((dcpl >= 0), "set property list for compact dataset");
    ret = H5Pset_alloc_time(dcpl, H5D_ALLOC_TIME_EARLY);
    VRFY((ret >= 0), "set space allocation time for compact dataset");

    dataset = H5Dcreate2(iof, dname, H5T_NATIVE_DOUBLE, filespace, H5P_DEFAULT, dcpl, H5P_DEFAULT);
    VRFY((dataset >= 0), "H5Dcreate2 succeeded");

    /* set up the collective transfer properties list */
    dxpl = H5Pcreate(H5P_DATASET_XFER);
    VRFY((dxpl >= 0), "");
    ret = H5Pset_dxpl_mpio(dxpl, H5FD_MPIO_COLLECTIVE);
    VRFY((ret >= 0), "H5Pcreate xfer succeeded");
    if (dxfer_coll_type == DXFER_INDEPENDENT_IO) {
        ret = H5Pset_dxpl_mpio_collective_opt(dxpl, H5FD_MPIO_INDIVIDUAL_IO);
        VRFY((ret >= 0), "set independent IO collectively succeeded");
    }

    /* Recalculate data to write.  Each process writes the same data. */
    for (i = 0; i < size; i++)
        for (j = 0; j < size; j++)
            outme[(i * size) + j] = (i + j) * 1000;

    ret = H5Dwrite(dataset, H5T_NATIVE_DOUBLE, H5S_ALL, H5S_ALL, dxpl, outme);
    VRFY((ret >= 0), "H5Dwrite succeeded");

    H5Pclose(dcpl);
    H5Pclose(plist);
    H5Dclose(dataset);
    H5Sclose(filespace);
    H5Fclose(iof);

    /* Open the file and dataset, read and compare the data. */
    plist = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    iof   = H5Fopen(filename, H5F_ACC_RDONLY, plist);
    VRFY((iof >= 0), "H5Fopen succeeded");

    /* set up the collective transfer properties list */
    dxpl = H5Pcreate(H5P_DATASET_XFER);
    VRFY((dxpl >= 0), "");
    ret = H5Pset_dxpl_mpio(dxpl, H5FD_MPIO_COLLECTIVE);
    VRFY((ret >= 0), "H5Pcreate xfer succeeded");
    if (dxfer_coll_type == DXFER_INDEPENDENT_IO) {
        ret = H5Pset_dxpl_mpio_collective_opt(dxpl, H5FD_MPIO_INDIVIDUAL_IO);
        VRFY((ret >= 0), "set independent IO collectively succeeded");
    }

    dataset = H5Dopen2(iof, dname, H5P_DEFAULT);
    VRFY((dataset >= 0), "H5Dopen2 succeeded");

#ifdef H5_HAVE_INSTRUMENTED_LIBRARY
    prop_value = H5D_XFER_COLL_RANK0_BCAST_DEF;
    ret = H5Pinsert2(dxpl, H5D_XFER_COLL_RANK0_BCAST_NAME, H5D_XFER_COLL_RANK0_BCAST_SIZE, &prop_value, NULL,
                     NULL, NULL, NULL, NULL, NULL);
    VRFY((ret >= 0), "H5Pinsert2() succeeded");
#endif /* H5_HAVE_INSTRUMENTED_LIBRARY */

    ret = H5Dread(dataset, H5T_NATIVE_DOUBLE, H5S_ALL, H5S_ALL, dxpl, inme);
    VRFY((ret >= 0), "H5Dread succeeded");

#ifdef H5_HAVE_INSTRUMENTED_LIBRARY
    prop_value = false;
    ret        = H5Pget(dxpl, H5D_XFER_COLL_RANK0_BCAST_NAME, &prop_value);
    VRFY((ret >= 0), "H5Pget succeeded");
    VRFY((prop_value == false && dxfer_coll_type == DXFER_COLLECTIVE_IO),
         "rank 0 Bcast optimization was performed for a compact dataset");
#endif /* H5_HAVE_INSTRUMENTED_LIBRARY */

    /* Verify data value */
    for (i = 0; i < size; i++)
        for (j = 0; j < size; j++)
            if (!H5_DBL_ABS_EQUAL(inme[(i * size) + j], outme[(i * size) + j]))
                if (err_num++ < MAX_ERR_REPORT || VERBOSE_MED)
                    printf("Dataset Verify failed at [%d][%d]: expect %f, got %f\n", i, j,
                           outme[(i * size) + j], inme[(i * size) + j]);

    H5Pclose(plist);
    H5Pclose(dxpl);
    H5Dclose(dataset);
    H5Fclose(iof);
    free(inme);
    free(outme);
}

/*
 * Example of using PHDF5 to create, write, and read dataset and attribute
 * of Null dataspace.
 */
void
null_dataset(void *params)
{
    int         mpi_size, mpi_rank;
    hid_t       iof, plist, dxpl, dataset, attr, sid;
    unsigned    uval = 2; /* Buffer for writing to dataset */
    int         val  = 1; /* Buffer for writing to attribute */
    hssize_t    nelem;
    char        dname[]     = "dataset";
    char        attr_name[] = "attribute";
    herr_t      ret;
    const char *filename;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC) ||
        !(vol_cap_flags_g & H5VL_CAP_FLAG_ATTR_BASIC)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf("    API functions for basic file, dataset, or attribute aren't supported with this "
                   "connector\n");
            fflush(stdout);
        }

        return;
    }

    filename = ((const H5Ptest_param_t *)params)->name;

    plist = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    iof   = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, plist);

    /* Define data space */
    sid = H5Screate(H5S_NULL);

    /* Check that the null dataspace actually has 0 elements */
    nelem = H5Sget_simple_extent_npoints(sid);
    VRFY((nelem == 0), "H5Sget_simple_extent_npoints");

    /* Create a compact dataset */
    dataset = H5Dcreate2(iof, dname, H5T_NATIVE_UINT, sid, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
    VRFY((dataset >= 0), "H5Dcreate2 succeeded");

    /* set up the collective transfer properties list */
    dxpl = H5Pcreate(H5P_DATASET_XFER);
    VRFY((dxpl >= 0), "");
    ret = H5Pset_dxpl_mpio(dxpl, H5FD_MPIO_COLLECTIVE);
    VRFY((ret >= 0), "H5Pcreate xfer succeeded");
    if (dxfer_coll_type == DXFER_INDEPENDENT_IO) {
        ret = H5Pset_dxpl_mpio_collective_opt(dxpl, H5FD_MPIO_INDIVIDUAL_IO);
        VRFY((ret >= 0), "set independent IO collectively succeeded");
    }

    /* Write "nothing" to the dataset(with type conversion) */
    ret = H5Dwrite(dataset, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, dxpl, &uval);
    VRFY((ret >= 0), "H5Dwrite succeeded");

    /* Create an attribute for the group */
    attr = H5Acreate2(dataset, attr_name, H5T_NATIVE_UINT, sid, H5P_DEFAULT, H5P_DEFAULT);
    VRFY((attr >= 0), "H5Acreate2");

    /* Write "nothing" to the attribute(with type conversion) */
    ret = H5Awrite(attr, H5T_NATIVE_INT, &val);
    VRFY((ret >= 0), "H5Awrite");

    H5Aclose(attr);
    H5Dclose(dataset);
    H5Pclose(plist);
    H5Sclose(sid);
    H5Fclose(iof);

    /* Open the file and dataset, read and compare the data. */
    plist = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    iof   = H5Fopen(filename, H5F_ACC_RDONLY, plist);
    VRFY((iof >= 0), "H5Fopen succeeded");

    /* set up the collective transfer properties list */
    dxpl = H5Pcreate(H5P_DATASET_XFER);
    VRFY((dxpl >= 0), "");
    ret = H5Pset_dxpl_mpio(dxpl, H5FD_MPIO_COLLECTIVE);
    VRFY((ret >= 0), "H5Pcreate xfer succeeded");
    if (dxfer_coll_type == DXFER_INDEPENDENT_IO) {
        ret = H5Pset_dxpl_mpio_collective_opt(dxpl, H5FD_MPIO_INDIVIDUAL_IO);
        VRFY((ret >= 0), "set independent IO collectively succeeded");
    }

    dataset = H5Dopen2(iof, dname, H5P_DEFAULT);
    VRFY((dataset >= 0), "H5Dopen2 succeeded");

    /* Try reading from the dataset(make certain our buffer is unmodified) */
    ret = H5Dread(dataset, H5T_NATIVE_UINT, H5S_ALL, H5S_ALL, dxpl, &uval);
    VRFY((ret >= 0), "H5Dread");
    VRFY((uval == 2), "H5Dread");

    /* Open the attribute for the dataset */
    attr = H5Aopen(dataset, attr_name, H5P_DEFAULT);
    VRFY((attr >= 0), "H5Aopen");

    /* Try reading from the attribute(make certain our buffer is unmodified) */ ret =
        H5Aread(attr, H5T_NATIVE_INT, &val);
    VRFY((ret >= 0), "H5Aread");
    VRFY((val == 1), "H5Aread");

    H5Pclose(plist);
    H5Pclose(dxpl);
    H5Aclose(attr);
    H5Dclose(dataset);
    H5Fclose(iof);
}

/* Example of using PHDF5 to create "large" datasets. (>2GB, >4GB, >8GB)
 * Actual data is _not_ written to these datasets.  Dataspaces are exact
 * sizes(2GB, 4GB, etc.), but the metadata for the file pushes the file over
 * the boundary of interest.
 */
void
big_dataset(void *params)
{
    int   mpi_size, mpi_rank;        /* MPI info */
    hid_t iof,                       /* File ID */
        fapl,                        /* File access property list ID */
        dataset,                     /* Dataset ID */
        filespace;                   /* Dataset's dataspace ID */
    hsize_t     file_dims[4];        /* Dimensions of dataspace */
    char        dname[] = "dataset"; /* Name of dataset */
    MPI_Offset  file_size;           /* Size of file on disk */
    bool        vol_is_native;
    herr_t      ret; /* Generic return value */
    const char *filename;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf("    API functions for basic file or dataset aren't supported with this connector\n");
            fflush(stdout);
        }

        return;
    }

    /* Verify MPI_Offset can handle larger than 2GB sizes */
    VRFY((sizeof(MPI_Offset) > 4), "sizeof(MPI_Offset)>4");

    filename = ((const H5Ptest_param_t *)params)->name;

    fapl = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    VRFY((fapl >= 0), "create_faccess_plist succeeded");

    /*
     * Create >2GB HDF5 file
     */
    iof = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
    VRFY((iof >= 0), "H5Fcreate succeeded");

    /* Check if native VOL is being used */
    VRFY((h5_using_native_vol(H5P_DEFAULT, iof, &vol_is_native) >= 0), "h5_using_native_vol");

    /* Define dataspace for 2GB dataspace */
    file_dims[0] = 2;
    file_dims[1] = 1024;
    file_dims[2] = 1024;
    file_dims[3] = 1024;
    filespace    = H5Screate_simple(4, file_dims, NULL);
    VRFY((filespace >= 0), "H5Screate_simple succeeded");

    dataset = H5Dcreate2(iof, dname, H5T_NATIVE_UCHAR, filespace, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
    VRFY((dataset >= 0), "H5Dcreate2 succeeded");

    /* Close all file objects */
    ret = H5Dclose(dataset);
    VRFY((ret >= 0), "H5Dclose succeeded");
    ret = H5Sclose(filespace);
    VRFY((ret >= 0), "H5Sclose succeeded");
    ret = H5Fclose(iof);
    VRFY((ret >= 0), "H5Fclose succeeded");

    if (vol_is_native) {
        /* Check that file of the correct size was created */
        file_size = h5_get_file_size(filename, fapl);
        VRFY((file_size == 2147485696ULL), "File is correct size(~2GB)");
    }

    /*
     * Create >4GB HDF5 file
     */
    iof = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
    VRFY((iof >= 0), "H5Fcreate succeeded");

    /* Define dataspace for 4GB dataspace */
    file_dims[0] = 4;
    file_dims[1] = 1024;
    file_dims[2] = 1024;
    file_dims[3] = 1024;
    filespace    = H5Screate_simple(4, file_dims, NULL);
    VRFY((filespace >= 0), "H5Screate_simple succeeded");

    dataset = H5Dcreate2(iof, dname, H5T_NATIVE_UCHAR, filespace, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
    VRFY((dataset >= 0), "H5Dcreate2 succeeded");

    /* Close all file objects */
    ret = H5Dclose(dataset);
    VRFY((ret >= 0), "H5Dclose succeeded");
    ret = H5Sclose(filespace);
    VRFY((ret >= 0), "H5Sclose succeeded");
    ret = H5Fclose(iof);
    VRFY((ret >= 0), "H5Fclose succeeded");

    if (vol_is_native) {
        /* Check that file of the correct size was created */
        file_size = h5_get_file_size(filename, fapl);
        VRFY((file_size == 4294969344ULL), "File is correct size(~4GB)");
    }

    /*
     * Create >8GB HDF5 file
     */
    iof = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
    VRFY((iof >= 0), "H5Fcreate succeeded");

    /* Define dataspace for 8GB dataspace */
    file_dims[0] = 8;
    file_dims[1] = 1024;
    file_dims[2] = 1024;
    file_dims[3] = 1024;
    filespace    = H5Screate_simple(4, file_dims, NULL);
    VRFY((filespace >= 0), "H5Screate_simple succeeded");

    dataset = H5Dcreate2(iof, dname, H5T_NATIVE_UCHAR, filespace, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
    VRFY((dataset >= 0), "H5Dcreate2 succeeded");

    /* Close all file objects */
    ret = H5Dclose(dataset);
    VRFY((ret >= 0), "H5Dclose succeeded");
    ret = H5Sclose(filespace);
    VRFY((ret >= 0), "H5Sclose succeeded");
    ret = H5Fclose(iof);
    VRFY((ret >= 0), "H5Fclose succeeded");

    if (vol_is_native) {
        /* Check that file of the correct size was created */
        file_size = h5_get_file_size(filename, fapl);
        VRFY((file_size == 8589936640ULL), "File is correct size(~8GB)");
    }

    /* Close fapl */
    ret = H5Pclose(fapl);
    VRFY((ret >= 0), "H5Pclose succeeded");
}

/* Example of using PHDF5 to read a partial written dataset.   The dataset does
 * not have actual data written to the entire raw data area and relies on the
 * default fill value of zeros to work correctly.
 */
void
dataset_fillvalue(void *params)
{
    int   mpi_size, mpi_rank;             /* MPI info */
    int   err_num;                        /* Number of errors */
    hid_t iof,                            /* File ID */
        fapl,                             /* File access property list ID */
        dxpl,                             /* Data transfer property list ID */
        dataset,                          /* Dataset ID */
        memspace,                         /* Memory dataspace ID */
        filespace;                        /* Dataset's dataspace ID */
    char        dname[]      = "dataset"; /* Name of dataset */
    hsize_t     dset_dims[4] = {0, 6, 7, 8};
    hsize_t     req_start[4] = {0, 0, 0, 0};
    hsize_t     req_count[4] = {1, 6, 7, 8};
    hsize_t     dset_size;           /* Dataset size */
    int        *rdata, *wdata;       /* Buffers for data to read and write */
    int        *twdata, *trdata;     /* Temporary pointer into buffer */
    int         acc, i, ii, j, k, l; /* Local index variables */
    herr_t      ret;                 /* Generic return value */
    const char *filename;
#ifdef H5_HAVE_INSTRUMENTED_LIBRARY
    bool prop_value;
#endif

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf("    API functions for basic file or dataset aren't supported with this connector\n");
            fflush(stdout);
        }

        return;
    }

    filename = ((const H5Ptest_param_t *)params)->name;

    /* Set the dataset dimension to be one row more than number of processes */
    /* and calculate the actual dataset size. */
    dset_dims[0] = (hsize_t)(mpi_size + 1);
    dset_size    = dset_dims[0] * dset_dims[1] * dset_dims[2] * dset_dims[3];

    /* Allocate space for the buffers */
    rdata = malloc((size_t)(dset_size * sizeof(int)));
    VRFY((rdata != NULL), "calloc succeeded for read buffer");
    wdata = malloc((size_t)(dset_size * sizeof(int)));
    VRFY((wdata != NULL), "malloc succeeded for write buffer");

    fapl = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    VRFY((fapl >= 0), "create_faccess_plist succeeded");

    /*
     * Create HDF5 file
     */
    iof = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl);
    VRFY((iof >= 0), "H5Fcreate succeeded");

    filespace = H5Screate_simple(4, dset_dims, NULL);
    VRFY((filespace >= 0), "File H5Screate_simple succeeded");

    dataset = H5Dcreate2(iof, dname, H5T_NATIVE_INT, filespace, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
    VRFY((dataset >= 0), "H5Dcreate2 succeeded");

    memspace = H5Screate_simple(4, dset_dims, NULL);
    VRFY((memspace >= 0), "Memory H5Screate_simple succeeded");

    /*
     * Read dataset before any data is written.
     */

    /* Create DXPL for I/O */
    dxpl = H5Pcreate(H5P_DATASET_XFER);
    VRFY((dxpl >= 0), "H5Pcreate succeeded");

#ifdef H5_HAVE_INSTRUMENTED_LIBRARY
    prop_value = H5D_XFER_COLL_RANK0_BCAST_DEF;
    ret = H5Pinsert2(dxpl, H5D_XFER_COLL_RANK0_BCAST_NAME, H5D_XFER_COLL_RANK0_BCAST_SIZE, &prop_value, NULL,
                     NULL, NULL, NULL, NULL, NULL);
    VRFY((ret >= 0), "testing property list inserted succeeded");
#endif /* H5_HAVE_INSTRUMENTED_LIBRARY */

    for (ii = 0; ii < 2; ii++) {

        if (ii == 0)
            ret = H5Pset_dxpl_mpio(dxpl, H5FD_MPIO_INDEPENDENT);
        else
            ret = H5Pset_dxpl_mpio(dxpl, H5FD_MPIO_COLLECTIVE);
        VRFY((ret >= 0), "H5Pset_dxpl_mpio succeeded");

        /* set entire read buffer with the constant 2 */
        memset(rdata, 2, (size_t)(dset_size * sizeof(int)));

        /* Read the entire dataset back */
        ret = H5Dread(dataset, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, dxpl, rdata);
        VRFY((ret >= 0), "H5Dread succeeded");

#ifdef H5_HAVE_INSTRUMENTED_LIBRARY
        prop_value = false;
        ret        = H5Pget(dxpl, H5D_XFER_COLL_RANK0_BCAST_NAME, &prop_value);
        VRFY((ret >= 0), "testing property list get succeeded");
        if (ii == 0)
            VRFY((prop_value == false), "correctly handled rank 0 Bcast");
        else
            VRFY((prop_value == true), "correctly handled rank 0 Bcast");
#endif /* H5_HAVE_INSTRUMENTED_LIBRARY */

        /* Verify all data read are the fill value 0 */
        trdata  = rdata;
        err_num = 0;
        for (i = 0; i < (int)dset_dims[0]; i++)
            for (j = 0; j < (int)dset_dims[1]; j++)
                for (k = 0; k < (int)dset_dims[2]; k++)
                    for (l = 0; l < (int)dset_dims[3]; l++, trdata++)
                        if (*trdata != 0)
                            if (err_num++ < MAX_ERR_REPORT || VERBOSE_MED)
                                printf(
                                    "Rank %d: Dataset Verify failed at [%d][%d][%d][%d]: expect 0, got %d\n",
                                    mpi_rank, i, j, k, l, *trdata);
        if (err_num > MAX_ERR_REPORT && !VERBOSE_MED)
            printf("Rank %d: [more errors ...]\n", mpi_rank);
        if (err_num) {
            printf("Rank %d: %d errors found in check_value\n", mpi_rank, err_num);
            nerrors++;
        }
    }

    /* Barrier to ensure all processes have completed the above test. */
    MPI_Barrier(MPI_COMM_WORLD);

    /*
     * Each process writes 1 row of data. Thus last row is not written.
     */
    /* Create hyperslabs in memory and file dataspaces */
    req_start[0] = (hsize_t)mpi_rank;
    ret          = H5Sselect_hyperslab(filespace, H5S_SELECT_SET, req_start, NULL, req_count, NULL);
    VRFY((ret >= 0), "H5Sselect_hyperslab succeeded on memory dataspace");
    ret = H5Sselect_hyperslab(memspace, H5S_SELECT_SET, req_start, NULL, req_count, NULL);
    VRFY((ret >= 0), "H5Sselect_hyperslab succeeded on memory dataspace");

    ret = H5Pset_dxpl_mpio(dxpl, H5FD_MPIO_COLLECTIVE);
    VRFY((ret >= 0), "H5Pset_dxpl_mpio succeeded");
    if (dxfer_coll_type == DXFER_INDEPENDENT_IO) {
        ret = H5Pset_dxpl_mpio_collective_opt(dxpl, H5FD_MPIO_INDIVIDUAL_IO);
        VRFY((ret >= 0), "set independent IO collectively succeeded");
    }

    /* Fill write buffer with some values */
    twdata = wdata;
    for (i = 0, acc = 0; i < (int)dset_dims[0]; i++)
        for (j = 0; j < (int)dset_dims[1]; j++)
            for (k = 0; k < (int)dset_dims[2]; k++)
                for (l = 0; l < (int)dset_dims[3]; l++)
                    *twdata++ = acc++;

    /* Collectively write a hyperslab of data to the dataset */
    ret = H5Dwrite(dataset, H5T_NATIVE_INT, memspace, filespace, dxpl, wdata);
    VRFY((ret >= 0), "H5Dwrite succeeded");

    /* Barrier here, to allow processes to sync */
    MPI_Barrier(MPI_COMM_WORLD);

    /*
     * Read dataset after partial write.
     */

#ifdef H5_HAVE_INSTRUMENTED_LIBRARY
    prop_value = H5D_XFER_COLL_RANK0_BCAST_DEF;
    ret        = H5Pset(dxpl, H5D_XFER_COLL_RANK0_BCAST_NAME, &prop_value);
    VRFY((ret >= 0), " H5Pset succeeded");
#endif /* H5_HAVE_INSTRUMENTED_LIBRARY */

    for (ii = 0; ii < 2; ii++) {

        if (ii == 0)
            ret = H5Pset_dxpl_mpio(dxpl, H5FD_MPIO_INDEPENDENT);
        else
            ret = H5Pset_dxpl_mpio(dxpl, H5FD_MPIO_COLLECTIVE);
        VRFY((ret >= 0), "H5Pset_dxpl_mpio succeeded");

        /* set entire read buffer with the constant 2 */
        memset(rdata, 2, (size_t)(dset_size * sizeof(int)));

        /* Read the entire dataset back */
        ret = H5Dread(dataset, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, dxpl, rdata);
        VRFY((ret >= 0), "H5Dread succeeded");

#ifdef H5_HAVE_INSTRUMENTED_LIBRARY
        prop_value = false;
        ret        = H5Pget(dxpl, H5D_XFER_COLL_RANK0_BCAST_NAME, &prop_value);
        VRFY((ret >= 0), "testing property list get succeeded");
        if (ii == 0)
            VRFY((prop_value == false), "correctly handled rank 0 Bcast");
        else
            VRFY((prop_value == true), "correctly handled rank 0 Bcast");
#endif /* H5_HAVE_INSTRUMENTED_LIBRARY */

        /* Verify correct data read */
        twdata  = wdata;
        trdata  = rdata;
        err_num = 0;
        for (i = 0; i < (int)dset_dims[0]; i++)
            for (j = 0; j < (int)dset_dims[1]; j++)
                for (k = 0; k < (int)dset_dims[2]; k++)
                    for (l = 0; l < (int)dset_dims[3]; l++, twdata++, trdata++)
                        if (i < mpi_size) {
                            if (*twdata != *trdata)
                                if (err_num++ < MAX_ERR_REPORT || VERBOSE_MED)
                                    printf("Dataset Verify failed at [%d][%d][%d][%d]: expect %d, got %d\n",
                                           i, j, k, l, *twdata, *trdata);
                        } /* end if */
                        else {
                            if (*trdata != 0)
                                if (err_num++ < MAX_ERR_REPORT || VERBOSE_MED)
                                    printf("Dataset Verify failed at [%d][%d][%d][%d]: expect 0, got %d\n", i,
                                           j, k, l, *trdata);
                        } /* end else */
        if (err_num > MAX_ERR_REPORT && !VERBOSE_MED)
            printf("[more errors ...]\n");
        if (err_num) {
            printf("%d errors found in check_value\n", err_num);
            nerrors++;
        }
    }

    /* Close all file objects */
    ret = H5Dclose(dataset);
    VRFY((ret >= 0), "H5Dclose succeeded");
    ret = H5Sclose(filespace);
    VRFY((ret >= 0), "H5Sclose succeeded");
    ret = H5Fclose(iof);
    VRFY((ret >= 0), "H5Fclose succeeded");

    /* Close memory dataspace */
    ret = H5Sclose(memspace);
    VRFY((ret >= 0), "H5Sclose succeeded");

    /* Close dxpl */
    ret = H5Pclose(dxpl);
    VRFY((ret >= 0), "H5Pclose succeeded");

    /* Close fapl */
    ret = H5Pclose(fapl);
    VRFY((ret >= 0), "H5Pclose succeeded");

    /* free the buffers */
    free(rdata);
    free(wdata);
}

/* combined cngrpw and ingrpr tests because ingrpr reads file created by cngrpw. */
void
collective_group_write_independent_group_read(void *params)
{
    collective_group_write(params);
    independent_group_read(params);
}

/* Write multiple groups with a chunked dataset in each group collectively.
 * These groups and datasets are for testing independent read later.
 */
void
collective_group_write(void *params)
{
    int                    mpi_rank, mpi_size, size;
    int                    i, j, m;
    char                   gname[64], dname[32];
    hid_t                  fid, gid, did, plist, dcpl, memspace, filespace;
    DATATYPE              *outme = NULL;
    hsize_t                chunk_origin[DIM];
    hsize_t                chunk_dims[DIM], file_dims[DIM], count[DIM];
    hsize_t                chunk_size[2]; /* Chunk dimensions - computed shortly */
    herr_t                 ret1, ret2;
    const H5Ptest_param_t *pt;
    char                  *filename;
    int                    ngroups;

    pt       = params;
    filename = pt->name;
    ngroups  = pt->count;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_GROUP_BASIC) ||
        !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf(
                "    API functions for basic file, group, or dataset aren't supported with this connector\n");
            fflush(stdout);
        }

        return;
    }

    size = get_size();

    chunk_size[0] = (hsize_t)(size / 2);
    chunk_size[1] = (hsize_t)(size / 2);

    outme = malloc((size_t)size * (size_t)size * sizeof(DATATYPE));
    VRFY((outme != NULL), "malloc succeeded for outme");

    plist = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    fid   = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, plist);
    VRFY((fid >= 0), "H5Fcreate");
    H5Pclose(plist);

    /* decide the hyperslab according to process number. */
    get_slab(chunk_origin, chunk_dims, count, file_dims, size);

    /* select hyperslab in memory and file spaces.  These two operations are
     * identical since the datasets are the same. */
    memspace  = H5Screate_simple(DIM, file_dims, NULL);
    ret1      = H5Sselect_hyperslab(memspace, H5S_SELECT_SET, chunk_origin, chunk_dims, count, chunk_dims);
    filespace = H5Screate_simple(DIM, file_dims, NULL);
    ret2      = H5Sselect_hyperslab(filespace, H5S_SELECT_SET, chunk_origin, chunk_dims, count, chunk_dims);
    VRFY((memspace >= 0), "memspace");
    VRFY((filespace >= 0), "filespace");
    VRFY((ret1 == 0), "mgroup memspace selection");
    VRFY((ret2 == 0), "mgroup filespace selection");

    dcpl = H5Pcreate(H5P_DATASET_CREATE);
    ret1 = H5Pset_chunk(dcpl, 2, chunk_size);
    VRFY((dcpl >= 0), "dataset creation property");
    VRFY((ret1 == 0), "set chunk for dataset creation property");

    /* creates ngroups groups under the root group, writes chunked
     * datasets in parallel. */
    for (m = 0; m < ngroups; m++) {
        snprintf(gname, sizeof(gname), "group%d", m);
        gid = H5Gcreate2(fid, gname, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
        VRFY((gid > 0), gname);

        snprintf(dname, sizeof(dname), "dataset%d", m);
        did = H5Dcreate2(gid, dname, H5T_NATIVE_INT, filespace, H5P_DEFAULT, dcpl, H5P_DEFAULT);
        VRFY((did > 0), dname);

        for (i = 0; i < size; i++)
            for (j = 0; j < size; j++)
                outme[(i * size) + j] = (i + j) * 1000 + mpi_rank;

        ret1 = H5Dwrite(did, H5T_NATIVE_INT, memspace, filespace, H5P_DEFAULT, outme);
        VRFY((ret1 == 0), "H5Dwrite");

        ret1 = H5Dclose(did);
        VRFY((ret1 == 0), "H5Dclose");

        ret1 = H5Gclose(gid);
        VRFY((ret1 == 0), "H5Gclose");

#ifdef BARRIER_CHECKS
        if (!((m + 1) % 10)) {
            printf("created %d groups\n", m + 1);
            MPI_Barrier(MPI_COMM_WORLD);
        }
#endif /* BARRIER_CHECKS */
    }

    H5Pclose(dcpl);
    H5Sclose(filespace);
    H5Sclose(memspace);

    ret1 = H5Fclose(fid);
    VRFY((ret1 == 0), "H5Fclose");

    free(outme);
}

/* Let two sets of processes open and read different groups and chunked
 * datasets independently.
 */
void
independent_group_read(void *params)
{
    int                    mpi_rank, m;
    hid_t                  plist, fid;
    const H5Ptest_param_t *pt;
    char                  *filename;
    int                    ngroups;
    herr_t                 ret;

    pt       = params;
    filename = pt->name;
    ngroups  = pt->count;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_GROUP_BASIC) ||
        !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf(
                "    API functions for basic file, group, or dataset aren't supported with this connector\n");
            fflush(stdout);
        }

        return;
    }

    plist = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    H5Pset_all_coll_metadata_ops(plist, false);

    fid = H5Fopen(filename, H5F_ACC_RDONLY, plist);
    VRFY((fid > 0), "H5Fopen");
    H5Pclose(plist);

    /* open groups and read datasets. Odd number processes read even number
     * groups from the end; even number processes read odd number groups
     * from the beginning. */
    if (mpi_rank % 2 == 0) {
        for (m = ngroups - 1; m == 0; m -= 2)
            group_dataset_read(fid, mpi_rank, m);
    }
    else {
        for (m = 0; m < ngroups; m += 2)
            group_dataset_read(fid, mpi_rank, m);
    }

    ret = H5Fclose(fid);
    VRFY((ret == 0), "H5Fclose");
}

/* Open and read datasets and compare data
 */
static void
group_dataset_read(hid_t fid, int mpi_rank, int m)
{
    int       ret, i, j, size;
    char      gname[64], dname[32];
    hid_t     gid, did;
    DATATYPE *outdata = NULL;
    DATATYPE *indata  = NULL;

    size = get_size();

    indata = (DATATYPE *)malloc((size_t)size * (size_t)size * sizeof(DATATYPE));
    VRFY((indata != NULL), "malloc succeeded for indata");

    outdata = (DATATYPE *)malloc((size_t)size * (size_t)size * sizeof(DATATYPE));
    VRFY((outdata != NULL), "malloc succeeded for outdata");

    /* open every group under root group. */
    snprintf(gname, sizeof(gname), "group%d", m);
    gid = H5Gopen2(fid, gname, H5P_DEFAULT);
    VRFY((gid > 0), gname);

    /* check the data. */
    snprintf(dname, sizeof(dname), "dataset%d", m);
    did = H5Dopen2(gid, dname, H5P_DEFAULT);
    VRFY((did > 0), dname);

    H5Dread(did, H5T_NATIVE_INT, H5S_ALL, H5S_ALL, H5P_DEFAULT, indata);

    /* this is the original value */
    for (i = 0; i < size; i++)
        for (j = 0; j < size; j++)
            outdata[(i * size) + j] = (i + j) * 1000 + mpi_rank;

    /* compare the original value(outdata) to the value in file(indata).*/
    ret = check_value(indata, outdata, size);
    VRFY((ret == 0), "check the data");

    ret = H5Dclose(did);
    VRFY((ret == 0), "H5Dclose");
    ret = H5Gclose(gid);
    VRFY((ret == 0), "H5Gclose");

    free(indata);
    free(outdata);
}

/*
 * Example of using PHDF5 to create multiple groups.  Under the root group,
 * it creates ngroups groups.  Under the first group just created, it creates
 * recursive subgroups of depth GROUP_DEPTH.  In each created group, it
 * generates NDATASETS datasets.  Each process write a hyperslab of an array
 * into the file.  The structure is like
 *
 *                             root group
 *                                 |
 *            ---------------------------- ... ... ------------------------
 *           |          |         |        ... ...  |                      |
 *       group0*+'   group1*+' group2*+'   ... ...             group ngroups*+'
 *           |
 *      1st_child_group*'
 *           |
 *      2nd_child_group*'
 *           |
 *           :
 *           :
 *           |
 * GROUP_DEPTHth_child_group*'
 *
 *      * means the group has dataset(s).
 *      + means the group has attribute(s).
 *      ' means the datasets in the groups have attribute(s).
 *
 */
void
multiple_group_write(void *params)
{
    int                    mpi_rank, mpi_size, size;
    int                    m;
    char                   gname[64];
    hid_t                  fid, gid, plist, memspace, filespace;
    hsize_t                chunk_origin[DIM];
    hsize_t                chunk_dims[DIM], file_dims[DIM], count[DIM];
    herr_t                 ret;
    const H5Ptest_param_t *pt;
    char                  *filename;
    int                    ngroups;

    pt       = params;
    filename = pt->name;
    ngroups  = pt->count;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_GROUP_BASIC) ||
        !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_ATTR_BASIC)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf("    API functions for basic file, group, dataset, or attribute aren't supported with "
                   "this connector\n");
            fflush(stdout);
        }

        return;
    }

    size = get_size();

    plist = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    fid   = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, plist);
    H5Pclose(plist);

    /* decide the hyperslab according to process number. */
    get_slab(chunk_origin, chunk_dims, count, file_dims, size);

    /* select hyperslab in memory and file spaces.  These two operations are
     * identical since the datasets are the same. */
    memspace = H5Screate_simple(DIM, file_dims, NULL);
    VRFY((memspace >= 0), "memspace");
    ret = H5Sselect_hyperslab(memspace, H5S_SELECT_SET, chunk_origin, chunk_dims, count, chunk_dims);
    VRFY((ret >= 0), "mgroup memspace selection");

    filespace = H5Screate_simple(DIM, file_dims, NULL);
    VRFY((filespace >= 0), "filespace");
    ret = H5Sselect_hyperslab(filespace, H5S_SELECT_SET, chunk_origin, chunk_dims, count, chunk_dims);
    VRFY((ret >= 0), "mgroup filespace selection");

    /* creates ngroups groups under the root group, writes datasets in
     * parallel. */
    for (m = 0; m < ngroups; m++) {
        snprintf(gname, sizeof(gname), "group%d", m);
        gid = H5Gcreate2(fid, gname, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
        VRFY((gid > 0), gname);

        /* create attribute for these groups. */
        write_attribute(gid, is_group, m);

        if (m != 0)
            write_dataset(memspace, filespace, gid);

        H5Gclose(gid);

#ifdef BARRIER_CHECKS
        if (!((m + 1) % 10)) {
            printf("created %d groups\n", m + 1);
            MPI_Barrier(MPI_COMM_WORLD);
        }
#endif /* BARRIER_CHECKS */
    }

    /* recursively creates subgroups under the first group. */
    gid = H5Gopen2(fid, "group0", H5P_DEFAULT);
    create_group_recursive(memspace, filespace, gid, 0);
    ret = H5Gclose(gid);
    VRFY((ret >= 0), "H5Gclose");

    ret = H5Sclose(filespace);
    VRFY((ret >= 0), "H5Sclose");
    ret = H5Sclose(memspace);
    VRFY((ret >= 0), "H5Sclose");
    ret = H5Fclose(fid);
    VRFY((ret >= 0), "H5Fclose");
}

/*
 * In a group, creates NDATASETS datasets.  Each process writes a hyperslab
 * of a data array to the file.
 */
static void
write_dataset(hid_t memspace, hid_t filespace, hid_t gid)
{
    int       i, j, n, size;
    int       mpi_rank, mpi_size;
    char      dname[32];
    DATATYPE *outme = NULL;
    hid_t     did;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    size = get_size();

    outme = malloc((size_t)size * (size_t)size * sizeof(double));
    VRFY((outme != NULL), "malloc succeeded for outme");

    for (n = 0; n < NDATASET; n++) {
        snprintf(dname, sizeof(dname), "dataset%d", n);
        did = H5Dcreate2(gid, dname, H5T_NATIVE_INT, filespace, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
        VRFY((did > 0), dname);

        for (i = 0; i < size; i++)
            for (j = 0; j < size; j++)
                outme[(i * size) + j] = n * 1000 + mpi_rank;

        H5Dwrite(did, H5T_NATIVE_INT, memspace, filespace, H5P_DEFAULT, outme);

        /* create attribute for these datasets.*/
        write_attribute(did, is_dset, n);

        H5Dclose(did);
    }
    free(outme);
}

/*
 * Creates subgroups of depth GROUP_DEPTH recursively.  Also writes datasets
 * in parallel in each group.
 */
static void
create_group_recursive(hid_t memspace, hid_t filespace, hid_t gid, int counter)
{
    hid_t child_gid;
    int   mpi_rank;
    char  gname[64];

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);

#ifdef BARRIER_CHECKS
    if (!((counter + 1) % 10)) {
        printf("created %dth child groups\n", counter + 1);
        MPI_Barrier(MPI_COMM_WORLD);
    }
#endif /* BARRIER_CHECKS */

    snprintf(gname, sizeof(gname), "%dth_child_group", counter + 1);
    child_gid = H5Gcreate2(gid, gname, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
    VRFY((child_gid > 0), gname);

    /* write datasets in parallel. */
    write_dataset(memspace, filespace, gid);

    if (counter < GROUP_DEPTH)
        create_group_recursive(memspace, filespace, child_gid, counter + 1);

    H5Gclose(child_gid);
}

/*
 * This function is to verify the data from multiple group testing.  It opens
 * every dataset in every group and check their correctness.
 */
void
multiple_group_read(void *params)
{
    int                    mpi_rank, mpi_size, error_num, size;
    int                    m;
    char                   gname[64];
    hid_t                  plist, fid, gid, memspace, filespace;
    hsize_t                chunk_origin[DIM];
    hsize_t                chunk_dims[DIM], file_dims[DIM], count[DIM];
    const H5Ptest_param_t *pt;
    char                  *filename;
    int                    ngroups;

    pt       = params;
    filename = pt->name;
    ngroups  = pt->count;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_GROUP_BASIC) ||
        !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_ATTR_BASIC)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf("    API functions for basic file, group, dataset, or attribute aren't supported with "
                   "this connector\n");
            fflush(stdout);
        }

        return;
    }

    size = get_size();

    plist = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    fid   = H5Fopen(filename, H5F_ACC_RDONLY, plist);
    H5Pclose(plist);

    /* decide hyperslab for each process */
    get_slab(chunk_origin, chunk_dims, count, file_dims, size);

    /* select hyperslab for memory and file space */
    memspace = H5Screate_simple(DIM, file_dims, NULL);
    H5Sselect_hyperslab(memspace, H5S_SELECT_SET, chunk_origin, chunk_dims, count, chunk_dims);
    filespace = H5Screate_simple(DIM, file_dims, NULL);
    H5Sselect_hyperslab(filespace, H5S_SELECT_SET, chunk_origin, chunk_dims, count, chunk_dims);

    /* open every group under root group. */
    for (m = 0; m < ngroups; m++) {
        snprintf(gname, sizeof(gname), "group%d", m);
        gid = H5Gopen2(fid, gname, H5P_DEFAULT);
        VRFY((gid > 0), gname);

        /* check the data. */
        if (m != 0)
            if ((error_num = read_dataset(memspace, filespace, gid)) > 0)
                nerrors += error_num;

        /* check attribute.*/
        error_num = 0;
        if ((error_num = read_attribute(gid, is_group, m)) > 0)
            nerrors += error_num;

        H5Gclose(gid);

#ifdef BARRIER_CHECKS
        if (!((m + 1) % 10))
            MPI_Barrier(MPI_COMM_WORLD);
#endif /* BARRIER_CHECKS */
    }

    /* open all the groups in vertical direction. */
    gid = H5Gopen2(fid, "group0", H5P_DEFAULT);
    VRFY((gid > 0), "group0");
    recursive_read_group(memspace, filespace, gid, 0);
    H5Gclose(gid);

    H5Sclose(filespace);
    H5Sclose(memspace);
    H5Fclose(fid);
}

/*
 * This function opens all the datasets in a certain, checks the data using
 * dataset_vrfy function.
 */
static int
read_dataset(hid_t memspace, hid_t filespace, hid_t gid)
{
    int       i, j, n, mpi_rank, mpi_size, size, attr_errors = 0, vrfy_errors = 0;
    char      dname[32];
    DATATYPE *outdata = NULL, *indata = NULL;
    hid_t     did;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    size = get_size();

    indata = (DATATYPE *)malloc((size_t)size * (size_t)size * sizeof(DATATYPE));
    VRFY((indata != NULL), "malloc succeeded for indata");

    outdata = (DATATYPE *)malloc((size_t)size * (size_t)size * sizeof(DATATYPE));
    VRFY((outdata != NULL), "malloc succeeded for outdata");

    for (n = 0; n < NDATASET; n++) {
        snprintf(dname, sizeof(dname), "dataset%d", n);
        did = H5Dopen2(gid, dname, H5P_DEFAULT);
        VRFY((did > 0), dname);

        H5Dread(did, H5T_NATIVE_INT, memspace, filespace, H5P_DEFAULT, indata);

        /* this is the original value */
        for (i = 0; i < size; i++)
            for (j = 0; j < size; j++) {
                *outdata = n * 1000 + mpi_rank;
                outdata++;
            }
        outdata -= size * size;

        /* compare the original value(outdata) to the value in file(indata).*/
        vrfy_errors = check_value(indata, outdata, size);

        /* check attribute.*/
        if ((attr_errors = read_attribute(did, is_dset, n)) > 0)
            vrfy_errors += attr_errors;

        H5Dclose(did);
    }

    free(indata);
    free(outdata);

    return vrfy_errors;
}

/*
 * This recursive function opens all the groups in vertical direction and
 * checks the data.
 */
static void
recursive_read_group(hid_t memspace, hid_t filespace, hid_t gid, int counter)
{
    hid_t child_gid;
    int   mpi_rank, err_num = 0;
    char  gname[64];

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
#ifdef BARRIER_CHECKS
    if ((counter + 1) % 10)
        MPI_Barrier(MPI_COMM_WORLD);
#endif /* BARRIER_CHECKS */

    if ((err_num = read_dataset(memspace, filespace, gid)))
        nerrors += err_num;

    if (counter < GROUP_DEPTH) {
        snprintf(gname, sizeof(gname), "%dth_child_group", counter + 1);
        child_gid = H5Gopen2(gid, gname, H5P_DEFAULT);
        VRFY((child_gid > 0), gname);
        recursive_read_group(memspace, filespace, child_gid, counter + 1);
        H5Gclose(child_gid);
    }
}

/* Create and write attribute for a group or a dataset.  For groups, attribute
 * is a scalar datum; for dataset, it is a one-dimensional array.
 */
static void
write_attribute(hid_t obj_id, int this_type, int num)
{
    hid_t   sid, aid;
    hsize_t dspace_dims[1] = {8};
    int     i, mpi_rank, attr_data[8], dspace_rank = 1;
    char    attr_name[32];

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);

    if (this_type == is_group) {
        snprintf(attr_name, sizeof(attr_name), "Group Attribute %d", num);
        sid = H5Screate(H5S_SCALAR);
        aid = H5Acreate2(obj_id, attr_name, H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT);
        H5Awrite(aid, H5T_NATIVE_INT, &num);
        H5Aclose(aid);
        H5Sclose(sid);
    } /* end if */
    else if (this_type == is_dset) {
        snprintf(attr_name, sizeof(attr_name), "Dataset Attribute %d", num);
        for (i = 0; i < 8; i++)
            attr_data[i] = i;
        sid = H5Screate_simple(dspace_rank, dspace_dims, NULL);
        aid = H5Acreate2(obj_id, attr_name, H5T_NATIVE_INT, sid, H5P_DEFAULT, H5P_DEFAULT);
        H5Awrite(aid, H5T_NATIVE_INT, attr_data);
        H5Aclose(aid);
        H5Sclose(sid);
    } /* end else-if */
}

/* Read and verify attribute for group or dataset. */
static int
read_attribute(hid_t obj_id, int this_type, int num)
{
    hid_t   aid;
    hsize_t group_block[2] = {1, 1}, dset_block[2] = {1, 8};
    int     i, mpi_rank, in_num, in_data[8], out_data[8], vrfy_errors = 0;
    char    attr_name[32];

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);

    if (this_type == is_group) {
        snprintf(attr_name, sizeof(attr_name), "Group Attribute %d", num);
        aid = H5Aopen(obj_id, attr_name, H5P_DEFAULT);
        H5Aread(aid, H5T_NATIVE_INT, &in_num);
        vrfy_errors = dataset_vrfy(NULL, NULL, NULL, group_block, &in_num, &num);
        H5Aclose(aid);
    }
    else if (this_type == is_dset) {
        snprintf(attr_name, sizeof(attr_name), "Dataset Attribute %d", num);
        for (i = 0; i < 8; i++)
            out_data[i] = i;
        aid = H5Aopen(obj_id, attr_name, H5P_DEFAULT);
        H5Aread(aid, H5T_NATIVE_INT, in_data);
        vrfy_errors = dataset_vrfy(NULL, NULL, NULL, dset_block, in_data, out_data);
        H5Aclose(aid);
    }

    return vrfy_errors;
}

/* This functions compares the original data with the read-in data for its
 * hyperslab part only by process ID.
 */
static int
check_value(DATATYPE *indata, DATATYPE *outdata, int size)
{
    int     mpi_rank, mpi_size, err_num = 0;
    hsize_t i, j;
    hsize_t chunk_origin[DIM];
    hsize_t chunk_dims[DIM], count[DIM];

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    get_slab(chunk_origin, chunk_dims, count, NULL, size);

    indata += chunk_origin[0] * (hsize_t)size;
    outdata += chunk_origin[0] * (hsize_t)size;
    for (i = chunk_origin[0]; i < (chunk_origin[0] + chunk_dims[0]); i++)
        for (j = chunk_origin[1]; j < (chunk_origin[1] + chunk_dims[1]); j++) {
            if (*indata != *outdata)
                if (err_num++ < MAX_ERR_REPORT || VERBOSE_MED)
                    printf("Dataset Verify failed at [%lu][%lu](row %lu, col%lu): expect %d, got %d\n",
                           (unsigned long)i, (unsigned long)j, (unsigned long)i, (unsigned long)j, *outdata,
                           *indata);
        }
    if (err_num > MAX_ERR_REPORT && !VERBOSE_MED)
        printf("[more errors ...]\n");
    if (err_num)
        printf("%d errors found in check_value\n", err_num);
    return err_num;
}

/* Decide the portion of data chunk in dataset by process ID.
 */

static void
get_slab(hsize_t chunk_origin[], hsize_t chunk_dims[], hsize_t count[], hsize_t file_dims[], int size)
{
    int mpi_rank, mpi_size;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    if (chunk_origin != NULL) {
        chunk_origin[0] = (hsize_t)mpi_rank * (hsize_t)(size / mpi_size);
        chunk_origin[1] = 0;
    }
    if (chunk_dims != NULL) {
        chunk_dims[0] = (hsize_t)(size / mpi_size);
        chunk_dims[1] = (hsize_t)size;
    }
    if (file_dims != NULL)
        file_dims[0] = file_dims[1] = (hsize_t)size;
    if (count != NULL)
        count[0] = count[1] = 1;
}

/*
 * This function is based on bug demonstration code provided by Thomas
 * Guignon(thomas.guignon@ifp.fr), and is intended to verify the
 * correctness of my fix for that bug.
 *
 * In essence, the bug appeared when at least one process attempted to
 * write a point selection -- for which collective I/O is not supported,
 * and at least one other attempted to write some other type of selection
 * for which collective I/O is supported.
 *
 * Since the processes did not compare notes before performing the I/O,
 * some would attempt collective I/O while others performed independent
 * I/O.  A hang resulted.
 *
 * This function reproduces this situation.  At present the test hangs
 * on failure.
 *                                         JRM - 9/13/04
 */

#define N 4

void
io_mode_confusion(void *params)
{
    /*
     * HDF5 APIs definitions
     */

    const int   rank         = 1;
    const char *dataset_name = "IntArray";

    hid_t file_id, dset_id;    /* file and dataset identifiers */
    hid_t filespace, memspace; /* file and memory dataspace */
                               /* identifiers               */
    hsize_t dimsf[1];          /* dataset dimensions */
    int     data[N]  = {1};    /* pointer to data buffer to write */
    hsize_t coord[N] = {0L, 1L, 2L, 3L};
    hid_t   plist_id; /* property list identifier */
    herr_t  status;

    /*
     * MPI variables
     */

    int mpi_size, mpi_rank;

    /*
     * test bed related variables
     */

    const char            *fcn_name = "io_mode_confusion";
    const bool             verbose  = false;
    const H5Ptest_param_t *pt;
    char                  *filename;

    pt       = params;
    filename = pt->name;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC) ||
        !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_MORE)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf("    API functions for basic file, dataset, or dataset more aren't supported with this "
                   "connector\n");
            fflush(stdout);
        }

        return;
    }

    /*
     * Set up file access property list with parallel I/O access
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: Setting up property list.\n", mpi_rank, fcn_name);

    plist_id = H5Pcreate(H5P_FILE_ACCESS);
    VRFY((plist_id != -1), "H5Pcreate() failed");

    status = H5Pset_fapl_mpio(plist_id, MPI_COMM_WORLD, MPI_INFO_NULL);
    VRFY((status >= 0), "H5Pset_fapl_mpio() failed");

    /*
     * Create a new file collectively and release property list identifier.
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: Creating new file.\n", mpi_rank, fcn_name);

    file_id = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, plist_id);
    VRFY((file_id >= 0), "H5Fcreate() failed");

    status = H5Pclose(plist_id);
    VRFY((status >= 0), "H5Pclose() failed");

    /*
     * Create the dataspace for the dataset.
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: Creating the dataspace for the dataset.\n", mpi_rank, fcn_name);

    dimsf[0]  = N;
    filespace = H5Screate_simple(rank, dimsf, NULL);
    VRFY((filespace >= 0), "H5Screate_simple() failed.");

    /*
     * Create the dataset with default properties and close filespace.
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: Creating the dataset, and closing filespace.\n", mpi_rank, fcn_name);

    dset_id =
        H5Dcreate2(file_id, dataset_name, H5T_NATIVE_INT, filespace, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT);
    VRFY((dset_id >= 0), "H5Dcreate2() failed");

    status = H5Sclose(filespace);
    VRFY((status >= 0), "H5Sclose() failed");

    if (verbose)
        fprintf(stdout, "%0d:%s: Calling H5Screate_simple().\n", mpi_rank, fcn_name);

    memspace = H5Screate_simple(rank, dimsf, NULL);
    VRFY((memspace >= 0), "H5Screate_simple() failed.");

    if (mpi_rank == 0) {
        if (verbose)
            fprintf(stdout, "%0d:%s: Calling H5Sselect_all(memspace).\n", mpi_rank, fcn_name);

        status = H5Sselect_all(memspace);
        VRFY((status >= 0), "H5Sselect_all() failed");
    }
    else {
        if (verbose)
            fprintf(stdout, "%0d:%s: Calling H5Sselect_none(memspace).\n", mpi_rank, fcn_name);

        status = H5Sselect_none(memspace);
        VRFY((status >= 0), "H5Sselect_none() failed");
    }

    if (verbose)
        fprintf(stdout, "%0d:%s: Calling MPI_Barrier().\n", mpi_rank, fcn_name);

    MPI_Barrier(MPI_COMM_WORLD);

    if (verbose)
        fprintf(stdout, "%0d:%s: Calling H5Dget_space().\n", mpi_rank, fcn_name);

    filespace = H5Dget_space(dset_id);
    VRFY((filespace >= 0), "H5Dget_space() failed");

    /* select all */
    if (mpi_rank == 0) {
        if (verbose)
            fprintf(stdout, "%0d:%s: Calling H5Sselect_elements() -- set up hang?\n", mpi_rank, fcn_name);

        status = H5Sselect_elements(filespace, H5S_SELECT_SET, N, (const hsize_t *)&coord);
        VRFY((status >= 0), "H5Sselect_elements() failed");
    }
    else { /* select nothing */
        if (verbose)
            fprintf(stdout, "%0d:%s: Calling H5Sselect_none().\n", mpi_rank, fcn_name);

        status = H5Sselect_none(filespace);
        VRFY((status >= 0), "H5Sselect_none() failed");
    }

    if (verbose)
        fprintf(stdout, "%0d:%s: Calling MPI_Barrier().\n", mpi_rank, fcn_name);

    MPI_Barrier(MPI_COMM_WORLD);

    if (verbose)
        fprintf(stdout, "%0d:%s: Calling H5Pcreate().\n", mpi_rank, fcn_name);

    plist_id = H5Pcreate(H5P_DATASET_XFER);
    VRFY((plist_id != -1), "H5Pcreate() failed");

    if (verbose)
        fprintf(stdout, "%0d:%s: Calling H5Pset_dxpl_mpio().\n", mpi_rank, fcn_name);

    status = H5Pset_dxpl_mpio(plist_id, H5FD_MPIO_COLLECTIVE);
    VRFY((status >= 0), "H5Pset_dxpl_mpio() failed");
    if (dxfer_coll_type == DXFER_INDEPENDENT_IO) {
        status = H5Pset_dxpl_mpio_collective_opt(plist_id, H5FD_MPIO_INDIVIDUAL_IO);
        VRFY((status >= 0), "set independent IO collectively succeeded");
    }

    if (verbose)
        fprintf(stdout, "%0d:%s: Calling H5Dwrite() -- hang here?.\n", mpi_rank, fcn_name);

    status = H5Dwrite(dset_id, H5T_NATIVE_INT, memspace, filespace, plist_id, data);

    if (verbose)
        fprintf(stdout, "%0d:%s: Returned from H5Dwrite(), status=%d.\n", mpi_rank, fcn_name, status);
    VRFY((status >= 0), "H5Dwrite() failed");

    /*
     * Close/release resources.
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: Cleaning up from test.\n", mpi_rank, fcn_name);

    status = H5Dclose(dset_id);
    VRFY((status >= 0), "H5Dclose() failed");

    status = H5Sclose(filespace);
    VRFY((status >= 0), "H5Dclose() failed");

    status = H5Sclose(memspace);
    VRFY((status >= 0), "H5Sclose() failed");

    status = H5Pclose(plist_id);
    VRFY((status >= 0), "H5Pclose() failed");

    status = H5Fclose(file_id);
    VRFY((status >= 0), "H5Fclose() failed");

    if (verbose)
        fprintf(stdout, "%0d:%s: Done.\n", mpi_rank, fcn_name);

    return;

} /* io_mode_confusion() */

#undef N

/*
 * At present, the object header code maintains an image of its on disk
 * representation, which is updates as necessary instead of generating on
 * request.
 *
 * Prior to the fix that this test in designed to verify, the image of the
 * on disk representation was only updated on flush -- not when the object
 * header was marked clean.
 *
 * This worked perfectly well as long as all writes of a given object
 * header were written from a single process.  However, with the implementation
 * of round robin metadata data writes in parallel HDF5, this is no longer
 * the case -- it is possible for a given object header to be flushed from
 * several different processes, with the object header simply being marked
 * clean in all other processes on each flush.  This resulted in NULL or
 * out of data object header information being written to disk.
 *
 * To repair this, I modified the object header code to update its
 * on disk image both on flush on when marked clean.
 *
 * This test is directed at verifying that the fix performs as expected.
 *
 * The test functions by creating a HDF5 file with several small datasets,
 * and then flushing the file.  This should result of at least one of
 * the associated object headers being flushed by a process other than
 * process 0.
 *
 * Then for each data set, add an attribute and flush the file again.
 *
 * Close the file and re-open it.
 *
 * Open the each of the data sets in turn.  If all opens are successful,
 * the test passes.  Otherwise the test fails.
 *
 * Note that this test will probably become irrelevant shortly, when we
 * land the journaling modifications on the trunk -- at which point all
 * cache clients will have to construct on disk images on demand.
 *
 *                        JRM -- 10/13/10
 */

#define NUM_DATA_SETS   4
#define LOCAL_DATA_SIZE 4
#define LARGE_ATTR_SIZE 256
/* Since all even and odd processes are split into writer and reader comm
 * respectively, process 0 and 1 in COMM_WORLD become the root process of
 * the writer and reader comm respectively.
 */
#define Writer_Root                  0
#define Reader_Root                  1
#define Reader_wait(mpi_err, xsteps) mpi_err = MPI_Bcast(&xsteps, 1, MPI_INT, Writer_Root, MPI_COMM_WORLD)
#define Reader_result(mpi_err, xsteps_done)                                                                  \
    mpi_err = MPI_Bcast(&xsteps_done, 1, MPI_INT, Reader_Root, MPI_COMM_WORLD)
#define Reader_check(mpi_err, xsteps, xsteps_done)                                                           \
    {                                                                                                        \
        Reader_wait(mpi_err, xsteps);                                                                        \
        Reader_result(mpi_err, xsteps_done);                                                                 \
    }

/* object names used by both rr_obj_hdr_flush_confusion and
 * rr_obj_hdr_flush_confusion_reader.
 */
const char *dataset_name[NUM_DATA_SETS] = {"dataset_0", "dataset_1", "dataset_2", "dataset_3"};
const char *att_name[NUM_DATA_SETS]     = {"attribute_0", "attribute_1", "attribute_2", "attribute_3"};
const char *lg_att_name[NUM_DATA_SETS]  = {"large_attribute_0", "large_attribute_1", "large_attribute_2",
                                           "large_attribute_3"};

void
rr_obj_hdr_flush_confusion(void *params)
{
    /* MPI variables */
    /* private communicator size and rank */
    int      mpi_size;
    int      mpi_rank;
    int      mrc;       /* mpi error code */
    int      is_reader; /* 1 for reader process; 0 for writer process. */
    MPI_Comm comm;

    /* test bed related variables */
    const char *fcn_name = "rr_obj_hdr_flush_confusion";
    const bool  verbose  = false;

    /* Create two new private communicators from MPI_COMM_WORLD.
     * Even and odd ranked processes go to comm_writers and comm_readers
     * respectively.
     */
    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_size);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC) ||
        !(vol_cap_flags_g & H5VL_CAP_FLAG_FLUSH_REFRESH) || !(vol_cap_flags_g & H5VL_CAP_FLAG_ATTR_BASIC) ||
        !(vol_cap_flags_g & H5VL_CAP_FLAG_ATTR_MORE)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf("    API functions for basic file, dataset, attribute, dataset more, attribute more, or "
                   "file flush aren't supported with this connector\n");
            fflush(stdout);
        }

        return;
    }

    assert(mpi_size > 2);

    is_reader = mpi_rank % 2;
    mrc       = MPI_Comm_split(MPI_COMM_WORLD, is_reader, mpi_rank, &comm);
    VRFY((mrc == MPI_SUCCESS), "MPI_Comm_split");

    /* The reader processes branches off to do reading
     * while the writer processes continues to do writing
     * Whenever writers finish one writing step, including a H5Fflush,
     * they inform the readers, via MPI_COMM_WORLD, to verify.
     * They will wait for the result from the readers before doing the next
     * step. When all steps are done, they inform readers to end.
     */
    if (is_reader)
        rr_obj_hdr_flush_confusion_reader(params, comm);
    else
        rr_obj_hdr_flush_confusion_writer(params, comm);

    MPI_Comm_free(&comm);
    if (verbose)
        fprintf(stdout, "%0d:%s: Done.\n", mpi_rank, fcn_name);

    return;

} /* rr_obj_hdr_flush_confusion() */

static void
rr_obj_hdr_flush_confusion_writer(const void *params, MPI_Comm comm)
{
    int     i;
    int     j;
    hid_t   file_id = H5I_INVALID_HID;
    hid_t   fapl_id = H5I_INVALID_HID;
    hid_t   dxpl_id = H5I_INVALID_HID;
    hid_t   att_id[NUM_DATA_SETS];
    hid_t   att_space[NUM_DATA_SETS];
    hid_t   lg_att_id[NUM_DATA_SETS];
    hid_t   lg_att_space[NUM_DATA_SETS];
    hid_t   disk_space[NUM_DATA_SETS];
    hid_t   mem_space[NUM_DATA_SETS];
    hid_t   dataset[NUM_DATA_SETS];
    hsize_t att_size[1];
    hsize_t lg_att_size[1];
    hsize_t disk_count[1];
    hsize_t disk_size[1];
    hsize_t disk_start[1];
    hsize_t mem_count[1];
    hsize_t mem_size[1];
    hsize_t mem_start[1];
    herr_t  err;
    double  data[LOCAL_DATA_SIZE];
    double  att[LOCAL_DATA_SIZE];
    double  lg_att[LARGE_ATTR_SIZE];

    /* MPI variables */
    /* world communication size and rank */
    int mpi_world_size;
    int mpi_world_rank;
    /* private communicator size and rank */
    int mpi_size;
    int mpi_rank;
    int mrc; /* mpi error code */
    /* steps to verify and have been verified */
    int steps      = 0;
    int steps_done = 0;

    /* test bed related variables */
    const char            *fcn_name = "rr_obj_hdr_flush_confusion_writer";
    const bool             verbose  = false;
    const H5Ptest_param_t *pt;
    char                  *filename;

    /*
     * setup test bed related variables:
     */

    pt       = params;
    filename = pt->name;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_world_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_world_size);
    MPI_Comm_rank(comm, &mpi_rank);
    MPI_Comm_size(comm, &mpi_size);

    /*
     * Set up file access property list with parallel I/O access
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: Setting up property list.\n", mpi_rank, fcn_name);

    fapl_id = H5Pcreate(H5P_FILE_ACCESS);
    VRFY((fapl_id != -1), "H5Pcreate(H5P_FILE_ACCESS) failed");

    err = H5Pset_fapl_mpio(fapl_id, comm, MPI_INFO_NULL);
    VRFY((err >= 0), "H5Pset_fapl_mpio() failed");

    /*
     * Create a new file collectively and release property list identifier.
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: Creating new file \"%s\".\n", mpi_rank, fcn_name, filename);

    file_id = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl_id);
    VRFY((file_id >= 0), "H5Fcreate() failed");

    err = H5Pclose(fapl_id);
    VRFY((err >= 0), "H5Pclose(fapl_id) failed");

    /*
     * Step 1: create the data sets and write data.
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: Creating the datasets.\n", mpi_rank, fcn_name);

    disk_size[0] = (hsize_t)(LOCAL_DATA_SIZE * mpi_size);
    mem_size[0]  = (hsize_t)(LOCAL_DATA_SIZE);

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

        disk_space[i] = H5Screate_simple(1, disk_size, NULL);
        VRFY((disk_space[i] >= 0), "H5Screate_simple(1) failed.\n");

        dataset[i] = H5Dcreate2(file_id, dataset_name[i], H5T_NATIVE_DOUBLE, disk_space[i], H5P_DEFAULT,
                                H5P_DEFAULT, H5P_DEFAULT);

        VRFY((dataset[i] >= 0), "H5Dcreate(1) failed.\n");
    }

    /*
     * setup data transfer property list
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: Setting up dxpl.\n", mpi_rank, fcn_name);

    dxpl_id = H5Pcreate(H5P_DATASET_XFER);
    VRFY((dxpl_id != -1), "H5Pcreate(H5P_DATASET_XFER) failed.\n");

    err = H5Pset_dxpl_mpio(dxpl_id, H5FD_MPIO_COLLECTIVE);
    VRFY((err >= 0), "H5Pset_dxpl_mpio(dxpl_id, H5FD_MPIO_COLLECTIVE) failed.\n");

    /*
     * write data to the data sets
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: Writing datasets.\n", mpi_rank, fcn_name);

    disk_count[0] = (hsize_t)(LOCAL_DATA_SIZE);
    disk_start[0] = (hsize_t)(LOCAL_DATA_SIZE * mpi_rank);
    mem_count[0]  = (hsize_t)(LOCAL_DATA_SIZE);
    mem_start[0]  = (hsize_t)(0);

    for (j = 0; j < LOCAL_DATA_SIZE; j++) {
        data[j] = (double)(mpi_rank + 1);
    }

    for (i = 0; i < NUM_DATA_SETS; i++) {
        err = H5Sselect_hyperslab(disk_space[i], H5S_SELECT_SET, disk_start, NULL, disk_count, NULL);
        VRFY((err >= 0), "H5Sselect_hyperslab(1) failed.\n");
        mem_space[i] = H5Screate_simple(1, mem_size, NULL);
        VRFY((mem_space[i] >= 0), "H5Screate_simple(2) failed.\n");
        err = H5Sselect_hyperslab(mem_space[i], H5S_SELECT_SET, mem_start, NULL, mem_count, NULL);
        VRFY((err >= 0), "H5Sselect_hyperslab(2) failed.\n");
        err = H5Dwrite(dataset[i], H5T_NATIVE_DOUBLE, mem_space[i], disk_space[i], dxpl_id, data);
        VRFY((err >= 0), "H5Dwrite(1) failed.\n");
        for (j = 0; j < LOCAL_DATA_SIZE; j++)
            data[j] *= 10.0;
    }

    /*
     * close the data spaces
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: closing dataspaces.\n", mpi_rank, fcn_name);

    for (i = 0; i < NUM_DATA_SETS; i++) {
        err = H5Sclose(disk_space[i]);
        VRFY((err >= 0), "H5Sclose(disk_space[i]) failed.\n");
        err = H5Sclose(mem_space[i]);
        VRFY((err >= 0), "H5Sclose(mem_space[i]) failed.\n");
    }

    /* End of Step 1: create the data sets and write data. */

    /*
     * flush the metadata cache
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: flushing metadata cache.\n", mpi_rank, fcn_name);
    err = H5Fflush(file_id, H5F_SCOPE_GLOBAL);
    VRFY((err >= 0), "H5Fflush(1) failed.\n");

    /* Tell the reader to check the file up to steps. */
    steps++;
    Reader_check(mrc, steps, steps_done);
    VRFY((MPI_SUCCESS == mrc), "Reader_check failed");

    /*
     * Step 2: write attributes to each dataset
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: writing attributes.\n", mpi_rank, fcn_name);

    att_size[0] = (hsize_t)(LOCAL_DATA_SIZE);
    for (j = 0; j < LOCAL_DATA_SIZE; j++) {
        att[j] = (double)(j + 1);
    }

    for (i = 0; i < NUM_DATA_SETS; i++) {
        att_space[i] = H5Screate_simple(1, att_size, NULL);
        VRFY((att_space[i] >= 0), "H5Screate_simple(3) failed.\n");
        att_id[i] =
            H5Acreate2(dataset[i], att_name[i], H5T_NATIVE_DOUBLE, att_space[i], H5P_DEFAULT, H5P_DEFAULT);
        VRFY((att_id[i] >= 0), "H5Acreate(1) failed.\n");
        err = H5Awrite(att_id[i], H5T_NATIVE_DOUBLE, att);
        VRFY((err >= 0), "H5Awrite(1) failed.\n");
        for (j = 0; j < LOCAL_DATA_SIZE; j++) {
            att[j] /= 10.0;
        }
    }

    /*
     * close attribute IDs and spaces
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: closing attr ids and spaces .\n", mpi_rank, fcn_name);

    for (i = 0; i < NUM_DATA_SETS; i++) {
        err = H5Sclose(att_space[i]);
        VRFY((err >= 0), "H5Sclose(att_space[i]) failed.\n");
        err = H5Aclose(att_id[i]);
        VRFY((err >= 0), "H5Aclose(att_id[i]) failed.\n");
    }

    /* End of Step 2: write attributes to each dataset */

    /*
     * flush the metadata cache again
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: flushing metadata cache.\n", mpi_rank, fcn_name);
    err = H5Fflush(file_id, H5F_SCOPE_GLOBAL);
    VRFY((err >= 0), "H5Fflush(2) failed.\n");

    /* Tell the reader to check the file up to steps. */
    steps++;
    Reader_check(mrc, steps, steps_done);
    VRFY((MPI_SUCCESS == mrc), "Reader_check failed");

    /*
     * Step 3: write large attributes to each dataset
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: writing large attributes.\n", mpi_rank, fcn_name);

    lg_att_size[0] = (hsize_t)(LARGE_ATTR_SIZE);

    for (j = 0; j < LARGE_ATTR_SIZE; j++) {
        lg_att[j] = (double)(j + 1);
    }

    for (i = 0; i < NUM_DATA_SETS; i++) {
        lg_att_space[i] = H5Screate_simple(1, lg_att_size, NULL);
        VRFY((lg_att_space[i] >= 0), "H5Screate_simple(4) failed.\n");
        lg_att_id[i] = H5Acreate2(dataset[i], lg_att_name[i], H5T_NATIVE_DOUBLE, lg_att_space[i], H5P_DEFAULT,
                                  H5P_DEFAULT);
        VRFY((lg_att_id[i] >= 0), "H5Acreate(2) failed.\n");
        err = H5Awrite(lg_att_id[i], H5T_NATIVE_DOUBLE, lg_att);
        VRFY((err >= 0), "H5Awrite(2) failed.\n");
        for (j = 0; j < LARGE_ATTR_SIZE; j++) {
            lg_att[j] /= 10.0;
        }
    }

    /* Step 3: write large attributes to each dataset */

    /*
     * flush the metadata cache yet again to clean the object headers.
     *
     * This is an attempt to create a situation where we have dirty
     * object header continuation chunks, but clean object headers
     * to verify a speculative bug fix -- it doesn't seem to work,
     * but I will leave the code in anyway, as the object header
     * code is going to change a lot in the near future.
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: flushing metadata cache.\n", mpi_rank, fcn_name);
    err = H5Fflush(file_id, H5F_SCOPE_GLOBAL);
    VRFY((err >= 0), "H5Fflush(3) failed.\n");

    /* Tell the reader to check the file up to steps. */
    steps++;
    Reader_check(mrc, steps, steps_done);
    VRFY((MPI_SUCCESS == mrc), "Reader_check failed");

    /*
     * Step 4: write different large attributes to each dataset
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: writing different large attributes.\n", mpi_rank, fcn_name);

    for (j = 0; j < LARGE_ATTR_SIZE; j++) {
        lg_att[j] = (double)(j + 2);
    }

    for (i = 0; i < NUM_DATA_SETS; i++) {
        err = H5Awrite(lg_att_id[i], H5T_NATIVE_DOUBLE, lg_att);
        VRFY((err >= 0), "H5Awrite(2) failed.\n");
        for (j = 0; j < LARGE_ATTR_SIZE; j++) {
            lg_att[j] /= 10.0;
        }
    }

    /* End of Step 4: write different large attributes to each dataset */

    /*
     * flush the metadata cache again
     */
    if (verbose)
        fprintf(stdout, "%0d:%s: flushing metadata cache.\n", mpi_rank, fcn_name);
    err = H5Fflush(file_id, H5F_SCOPE_GLOBAL);
    VRFY((err >= 0), "H5Fflush(3) failed.\n");

    /* Tell the reader to check the file up to steps. */
    steps++;
    Reader_check(mrc, steps, steps_done);
    VRFY((MPI_SUCCESS == mrc), "Reader_check failed");

    /* Step 5: Close all objects and the file */

    /*
     * close large attribute IDs and spaces
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: closing large attr ids and spaces .\n", mpi_rank, fcn_name);

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

        err = H5Sclose(lg_att_space[i]);
        VRFY((err >= 0), "H5Sclose(lg_att_space[i]) failed.\n");
        err = H5Aclose(lg_att_id[i]);
        VRFY((err >= 0), "H5Aclose(lg_att_id[i]) failed.\n");
    }

    /*
     * close the data sets
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: closing datasets .\n", mpi_rank, fcn_name);

    for (i = 0; i < NUM_DATA_SETS; i++) {
        err = H5Dclose(dataset[i]);
        VRFY((err >= 0), "H5Dclose(dataset[i])1 failed.\n");
    }

    /*
     * close the data transfer property list.
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: closing dxpl .\n", mpi_rank, fcn_name);

    err = H5Pclose(dxpl_id);
    VRFY((err >= 0), "H5Pclose(dxpl_id) failed.\n");

    /*
     * Close file.
     */

    if (verbose)
        fprintf(stdout, "%0d:%s: closing file.\n", mpi_rank, fcn_name);

    err = H5Fclose(file_id);
    VRFY((err >= 0), "H5Fclose(1) failed");

    /* End of Step 5: Close all objects and the file */
    /* Tell the reader to check the file up to steps. */
    steps++;
    Reader_check(mrc, steps, steps_done);
    VRFY((MPI_SUCCESS == mrc), "Reader_check failed");

    /* All done. Inform reader to end. */
    steps = 0;
    Reader_check(mrc, steps, steps_done);
    VRFY((MPI_SUCCESS == mrc), "Reader_check failed");

    if (verbose)
        fprintf(stdout, "%0d:%s: Done.\n", mpi_rank, fcn_name);

    return;

} /* rr_obj_hdr_flush_confusion_writer() */

static void
rr_obj_hdr_flush_confusion_reader(const void *params, MPI_Comm comm)
{
    int     i;
    int     j;
    hid_t   file_id = H5I_INVALID_HID;
    hid_t   fapl_id = H5I_INVALID_HID;
    hid_t   dxpl_id = H5I_INVALID_HID;
    hid_t   lg_att_id[NUM_DATA_SETS];
    hid_t   lg_att_type[NUM_DATA_SETS];
    hid_t   disk_space[NUM_DATA_SETS];
    hid_t   mem_space[NUM_DATA_SETS];
    hid_t   dataset[NUM_DATA_SETS];
    hsize_t disk_count[1];
    hsize_t disk_start[1];
    hsize_t mem_count[1];
    hsize_t mem_size[1];
    hsize_t mem_start[1];
    herr_t  err;
    htri_t  tri_err;
    double  data[LOCAL_DATA_SIZE];
    double  data_read[LOCAL_DATA_SIZE];
    double  att[LOCAL_DATA_SIZE];
    double  att_read[LOCAL_DATA_SIZE];
    double  lg_att[LARGE_ATTR_SIZE];
    double  lg_att_read[LARGE_ATTR_SIZE];

    /* MPI variables */
    /* world communication size and rank */
    int mpi_world_size;
    int mpi_world_rank;
    /* private communicator size and rank */
    int mpi_size;
    int mpi_rank;
    int mrc;             /* mpi error code */
    int steps      = -1; /* How far (steps) to verify the file */
    int steps_done = -1; /* How far (steps) have been verified */

    /* test bed related variables */
    const char            *fcn_name = "rr_obj_hdr_flush_confusion_reader";
    const bool             verbose  = false;
    const H5Ptest_param_t *pt;
    char                  *filename;

    /*
     * setup test bed related variables:
     */

    pt       = params;
    filename = pt->name;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_world_rank);
    MPI_Comm_size(MPI_COMM_WORLD, &mpi_world_size);
    MPI_Comm_rank(comm, &mpi_rank);
    MPI_Comm_size(comm, &mpi_size);

    /* Repeatedly re-open the file and verify its contents until it is */
    /* told to end (when steps=0). */
    while (steps_done != 0) {
        Reader_wait(mrc, steps);
        VRFY((mrc >= 0), "Reader_wait failed");
        steps_done = 0;

        if (steps > 0) {
            /*
             * Set up file access property list with parallel I/O access
             */

            if (verbose)
                fprintf(stdout, "%0d:%s: Setting up property list.\n", mpi_rank, fcn_name);

            fapl_id = H5Pcreate(H5P_FILE_ACCESS);
            VRFY((fapl_id != -1), "H5Pcreate(H5P_FILE_ACCESS) failed");
            err = H5Pset_fapl_mpio(fapl_id, comm, MPI_INFO_NULL);
            VRFY((err >= 0), "H5Pset_fapl_mpio() failed");

            /*
             * Create a new file collectively and release property list identifier.
             */

            if (verbose)
                fprintf(stdout, "%0d:%s: Re-open file \"%s\".\n", mpi_rank, fcn_name, filename);

            file_id = H5Fopen(filename, H5F_ACC_RDONLY, fapl_id);
            VRFY((file_id >= 0), "H5Fopen() failed");
            err = H5Pclose(fapl_id);
            VRFY((err >= 0), "H5Pclose(fapl_id) failed");

#if 1
            if (steps >= 1) {
                /*=====================================================*
                 * Step 1: open the data sets and read data.
                 *=====================================================*/

                if (verbose)
                    fprintf(stdout, "%0d:%s: opening the datasets.\n", mpi_rank, fcn_name);

                for (i = 0; i < NUM_DATA_SETS; i++) {
                    dataset[i] = -1;
                }

                for (i = 0; i < NUM_DATA_SETS; i++) {
                    dataset[i] = H5Dopen2(file_id, dataset_name[i], H5P_DEFAULT);
                    VRFY((dataset[i] >= 0), "H5Dopen(1) failed.\n");
                    disk_space[i] = H5Dget_space(dataset[i]);
                    VRFY((disk_space[i] >= 0), "H5Dget_space failed.\n");
                }

                /*
                 * setup data transfer property list
                 */

                if (verbose)
                    fprintf(stdout, "%0d:%s: Setting up dxpl.\n", mpi_rank, fcn_name);

                dxpl_id = H5Pcreate(H5P_DATASET_XFER);
                VRFY((dxpl_id != -1), "H5Pcreate(H5P_DATASET_XFER) failed.\n");
                err = H5Pset_dxpl_mpio(dxpl_id, H5FD_MPIO_COLLECTIVE);
                VRFY((err >= 0), "H5Pset_dxpl_mpio(dxpl_id, H5FD_MPIO_COLLECTIVE) failed.\n");

                /*
                 * read data from the data sets
                 */

                if (verbose)
                    fprintf(stdout, "%0d:%s: Reading datasets.\n", mpi_rank, fcn_name);

                disk_count[0] = (hsize_t)(LOCAL_DATA_SIZE);
                disk_start[0] = (hsize_t)(LOCAL_DATA_SIZE * mpi_rank);

                mem_size[0] = (hsize_t)(LOCAL_DATA_SIZE);

                mem_count[0] = (hsize_t)(LOCAL_DATA_SIZE);
                mem_start[0] = (hsize_t)(0);

                /* set up expected data for verification */
                for (j = 0; j < LOCAL_DATA_SIZE; j++) {
                    data[j] = (double)(mpi_rank + 1);
                }

                for (i = 0; i < NUM_DATA_SETS; i++) {
                    err = H5Sselect_hyperslab(disk_space[i], H5S_SELECT_SET, disk_start, NULL, disk_count,
                                              NULL);
                    VRFY((err >= 0), "H5Sselect_hyperslab(1) failed.\n");
                    mem_space[i] = H5Screate_simple(1, mem_size, NULL);
                    VRFY((mem_space[i] >= 0), "H5Screate_simple(2) failed.\n");
                    err = H5Sselect_hyperslab(mem_space[i], H5S_SELECT_SET, mem_start, NULL, mem_count, NULL);
                    VRFY((err >= 0), "H5Sselect_hyperslab(2) failed.\n");
                    err = H5Dread(dataset[i], H5T_NATIVE_DOUBLE, mem_space[i], disk_space[i], dxpl_id,
                                  data_read);
                    VRFY((err >= 0), "H5Dread(1) failed.\n");

                    /* compare read data with expected data */
                    for (j = 0; j < LOCAL_DATA_SIZE; j++)
                        if (!H5_DBL_ABS_EQUAL(data_read[j], data[j])) {
                            fprintf(stdout,
                                    "%0d:%s: Reading datasets value failed in "
                                    "Dataset %d, at position %d: expect %f, got %f.\n",
                                    mpi_rank, fcn_name, i, j, data[j], data_read[j]);
                            nerrors++;
                        }
                    for (j = 0; j < LOCAL_DATA_SIZE; j++)
                        data[j] *= 10.0;
                }

                /*
                 * close the data spaces
                 */

                if (verbose)
                    fprintf(stdout, "%0d:%s: closing dataspaces.\n", mpi_rank, fcn_name);

                for (i = 0; i < NUM_DATA_SETS; i++) {
                    err = H5Sclose(disk_space[i]);
                    VRFY((err >= 0), "H5Sclose(disk_space[i]) failed.\n");
                    err = H5Sclose(mem_space[i]);
                    VRFY((err >= 0), "H5Sclose(mem_space[i]) failed.\n");
                }
                steps_done++;
            }
            /* End of Step 1: open the data sets and read data. */
#endif

#if 1
            /*=====================================================*
             * Step 2: reading attributes from each dataset
             *=====================================================*/

            if (steps >= 2) {
                if (verbose)
                    fprintf(stdout, "%0d:%s: reading attributes.\n", mpi_rank, fcn_name);

                for (j = 0; j < LOCAL_DATA_SIZE; j++) {
                    att[j] = (double)(j + 1);
                }

                for (i = 0; i < NUM_DATA_SETS; i++) {
                    hid_t att_id, att_type;

                    att_id = H5Aopen(dataset[i], att_name[i], H5P_DEFAULT);
                    VRFY((att_id >= 0), "H5Aopen failed.\n");
                    att_type = H5Aget_type(att_id);
                    VRFY((att_type >= 0), "H5Aget_type failed.\n");
                    tri_err = H5Tequal(att_type, H5T_NATIVE_DOUBLE);
                    VRFY((tri_err >= 0), "H5Tequal failed.\n");
                    if (tri_err == 0) {
                        fprintf(stdout, "%0d:%s: Mismatched Attribute type of Dataset %d.\n", mpi_rank,
                                fcn_name, i);
                        nerrors++;
                    }
                    else {
                        /* should verify attribute size before H5Aread */
                        err = H5Aread(att_id, H5T_NATIVE_DOUBLE, att_read);
                        VRFY((err >= 0), "H5Aread failed.\n");
                        /* compare read attribute data with expected data */
                        for (j = 0; j < LOCAL_DATA_SIZE; j++)
                            if (!H5_DBL_ABS_EQUAL(att_read[j], att[j])) {
                                fprintf(stdout,
                                        "%0d:%s: Mismatched attribute data read in Dataset %d, at position "
                                        "%d: expect %f, got %f.\n",
                                        mpi_rank, fcn_name, i, j, att[j], att_read[j]);
                                nerrors++;
                            }
                        for (j = 0; j < LOCAL_DATA_SIZE; j++) {
                            att[j] /= 10.0;
                        }
                    }
                    err = H5Aclose(att_id);
                    VRFY((err >= 0), "H5Aclose failed.\n");
                }
                steps_done++;
            }
            /* End of Step 2: reading attributes from each dataset */
#endif

#if 1
            /*=====================================================*
             * Step 3 or 4: read large attributes from each dataset.
             * Step 4 has different attribute value from step 3.
             *=====================================================*/

            if (steps >= 3) {
                if (verbose)
                    fprintf(stdout, "%0d:%s: reading large attributes.\n", mpi_rank, fcn_name);

                for (j = 0; j < LARGE_ATTR_SIZE; j++) {
                    lg_att[j] = (steps == 3) ? (double)(j + 1) : (double)(j + 2);
                }

                for (i = 0; i < NUM_DATA_SETS; i++) {
                    lg_att_id[i] = H5Aopen(dataset[i], lg_att_name[i], H5P_DEFAULT);
                    VRFY((lg_att_id[i] >= 0), "H5Aopen(2) failed.\n");
                    lg_att_type[i] = H5Aget_type(lg_att_id[i]);
                    VRFY((err >= 0), "H5Aget_type failed.\n");
                    tri_err = H5Tequal(lg_att_type[i], H5T_NATIVE_DOUBLE);
                    VRFY((tri_err >= 0), "H5Tequal failed.\n");
                    if (tri_err == 0) {
                        fprintf(stdout, "%0d:%s: Mismatched Large attribute type of Dataset %d.\n", mpi_rank,
                                fcn_name, i);
                        nerrors++;
                    }
                    else {
                        /* should verify large attribute size before H5Aread */
                        err = H5Aread(lg_att_id[i], H5T_NATIVE_DOUBLE, lg_att_read);
                        VRFY((err >= 0), "H5Aread failed.\n");
                        /* compare read attribute data with expected data */
                        for (j = 0; j < LARGE_ATTR_SIZE; j++)
                            if (!H5_DBL_ABS_EQUAL(lg_att_read[j], lg_att[j])) {
                                fprintf(stdout,
                                        "%0d:%s: Mismatched large attribute data read in Dataset %d, at "
                                        "position %d: expect %f, got %f.\n",
                                        mpi_rank, fcn_name, i, j, lg_att[j], lg_att_read[j]);
                                nerrors++;
                            }
                        for (j = 0; j < LARGE_ATTR_SIZE; j++) {

                            lg_att[j] /= 10.0;
                        }
                    }
                    err = H5Tclose(lg_att_type[i]);
                    VRFY((err >= 0), "H5Tclose failed.\n");
                    err = H5Aclose(lg_att_id[i]);
                    VRFY((err >= 0), "H5Aclose failed.\n");
                }
                /* Both step 3 and 4 use this same read checking code. */
                steps_done = (steps == 3) ? 3 : 4;
            }

            /* End of Step 3 or 4: read large attributes from each dataset */
#endif

            /*=====================================================*
             * Step 5: read all objects from the file
             *=====================================================*/
            if (steps >= 5) {
                /* nothing extra to verify. The file is closed normally. */
                /* Just increment steps_done */
                steps_done++;
            }

            /*
             * Close the data sets
             */

            if (verbose)
                fprintf(stdout, "%0d:%s: closing datasets again.\n", mpi_rank, fcn_name);

            for (i = 0; i < NUM_DATA_SETS; i++) {
                if (dataset[i] >= 0) {
                    err = H5Dclose(dataset[i]);
                    VRFY((err >= 0), "H5Dclose(dataset[i])1 failed.\n");
                }
            }

            /*
             * close the data transfer property list.
             */

            if (verbose)
                fprintf(stdout, "%0d:%s: closing dxpl .\n", mpi_rank, fcn_name);

            err = H5Pclose(dxpl_id);
            VRFY((err >= 0), "H5Pclose(dxpl_id) failed.\n");

            /*
             * Close the file
             */
            if (verbose)
                fprintf(stdout, "%0d:%s: closing file again.\n", mpi_rank, fcn_name);
            err = H5Fclose(file_id);
            VRFY((err >= 0), "H5Fclose(1) failed");

        } /* else if (steps_done==0) */
        Reader_result(mrc, steps_done);
    } /* end while(1) */

    if (verbose)
        fprintf(stdout, "%0d:%s: Done.\n", mpi_rank, fcn_name);

    return;
} /* rr_obj_hdr_flush_confusion_reader() */

#undef NUM_DATA_SETS
#undef LOCAL_DATA_SIZE
#undef LARGE_ATTR_SIZE
#undef Reader_check
#undef Reader_wait
#undef Reader_result
#undef Writer_Root
#undef Reader_Root

/*
 * Test creating a chunked dataset in parallel in a file with an alignment set
 * and an alignment threshold large enough to avoid aligning the chunks but
 * small enough that the raw data aggregator will be aligned if it is treated as
 * an object that must be aligned by the library
 */
#define CHUNK_SIZE  72
#define NCHUNKS     32
#define AGGR_SIZE   2048
#define EXTRA_ALIGN 100

void
chunk_align_bug_1(void *params)
{
    int            mpi_rank;
    hid_t          file_id, dset_id, fapl_id, dcpl_id, space_id;
    hsize_t        dims = CHUNK_SIZE * NCHUNKS, cdims = CHUNK_SIZE;
    h5_stat_size_t file_size;
    hsize_t        align = 1;
    bool           vol_is_native;
    herr_t         ret;
    const char    *filename;

    MPI_Comm_rank(MPI_COMM_WORLD, &mpi_rank);

    /* Make sure the connector supports the API functions being tested */
    if (!(vol_cap_flags_g & H5VL_CAP_FLAG_FILE_BASIC) || !(vol_cap_flags_g & H5VL_CAP_FLAG_DATASET_BASIC)) {
        if (MAINPROCESS) {
            puts("SKIPPED");
            printf("    API functions for basic file or dataset aren't supported with this connector\n");
            fflush(stdout);
        }

        return;
    }

    filename = ((const H5Ptest_param_t *)params)->name;

    /* Create file without alignment */
    fapl_id = create_faccess_plist(MPI_COMM_WORLD, MPI_INFO_NULL, facc_type);
    VRFY((fapl_id >= 0), "create_faccess_plist succeeded");
    file_id = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl_id);
    VRFY((file_id >= 0), "H5Fcreate succeeded");

    /* Check if native VOL is being used */
    VRFY((h5_using_native_vol(H5P_DEFAULT, file_id, &vol_is_native) >= 0), "h5_using_native_vol");

    /* Close file */
    ret = H5Fclose(file_id);
    VRFY((ret >= 0), "H5Fclose succeeded");

    if (vol_is_native) {
        /* Get file size */
        file_size = h5_get_file_size(filename, fapl_id);
        VRFY((file_size >= 0), "h5_get_file_size succeeded");

        /* Calculate alignment value, set to allow a chunk to squeak in between the
         * original EOF and the aligned location of the aggregator.  Add some space
         * for the dataset metadata */
        align = (hsize_t)file_size + CHUNK_SIZE + EXTRA_ALIGN;
    }

    /* Set aggregator size and alignment, disable metadata aggregator */
    assert(AGGR_SIZE > CHUNK_SIZE);
    ret = H5Pset_small_data_block_size(fapl_id, AGGR_SIZE);
    VRFY((ret >= 0), "H5Pset_small_data_block_size succeeded");
    ret = H5Pset_meta_block_size(fapl_id, 0);
    VRFY((ret >= 0), "H5Pset_meta_block_size succeeded");
    ret = H5Pset_alignment(fapl_id, CHUNK_SIZE + 1, align);
    VRFY((ret >= 0), "H5Pset_small_data_block_size succeeded");

    /* Reopen file with new settings */
    file_id = H5Fopen(filename, H5F_ACC_RDWR, fapl_id);
    VRFY((file_id >= 0), "H5Fopen succeeded");

    /* Create dataset */
    space_id = H5Screate_simple(1, &dims, NULL);
    VRFY((space_id >= 0), "H5Screate_simple succeeded");
    dcpl_id = H5Pcreate(H5P_DATASET_CREATE);
    VRFY((dcpl_id >= 0), "H5Pcreate succeeded");
    ret = H5Pset_chunk(dcpl_id, 1, &cdims);
    VRFY((ret >= 0), "H5Pset_chunk succeeded");
    dset_id = H5Dcreate2(file_id, "dset", H5T_NATIVE_CHAR, space_id, H5P_DEFAULT, dcpl_id, H5P_DEFAULT);
    VRFY((dset_id >= 0), "H5Dcreate2 succeeded");

    /* Close ids */
    ret = H5Dclose(dset_id);
    VRFY((dset_id >= 0), "H5Dclose succeeded");
    ret = H5Sclose(space_id);
    VRFY((space_id >= 0), "H5Sclose succeeded");
    ret = H5Pclose(dcpl_id);
    VRFY((dcpl_id >= 0), "H5Pclose succeeded");
    ret = H5Pclose(fapl_id);
    VRFY((fapl_id >= 0), "H5Pclose succeeded");

    /* Close file */
    ret = H5Fclose(file_id);
    VRFY((ret >= 0), "H5Fclose succeeded");

    return;
} /* end chunk_align_bug_1() */

/*=============================================================================
 *                         End of t_mdset.c
 *===========================================================================*/
