path: root/test/external.c

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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 COPYING 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.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/*
 * Purpose:    Tests datasets stored in external raw files.
 */
#include "external_common.h"
#include "external_fname.h"

#define AEF_EXNAME_MAX_LEN 12 /* string buffer size for external file name */
                              /* used in __add_external_files()            */

/*-------------------------------------------------------------------------
 * Function:    files_have_same_contents
 *
 * Purpose:     Determines whether two files contain the same data.
 *
 * Return:      Success:    nonzero if same, zero if different.
 *              Failure:    zero
 *
 *-------------------------------------------------------------------------
 */
static bool
files_have_same_contents(const char *name1, const char *name2)
{
    int     fd1 = 0;
    int     fd2 = 0;
    ssize_t n1  = 0;
    ssize_t n2  = 0;
    char    buf1[1024];
    char    buf2[1024];
    bool    ret = false; /* not equal until proven otherwise */

    if ((fd1 = HDopen(name1, O_RDONLY)) < 0)
        goto out;
    if ((fd2 = HDopen(name2, O_RDONLY)) < 0)
        goto out;

    /* Loop until files are empty or we encounter a problem */
    while (1) {
        memset(buf1, 0, sizeof(buf1));
        memset(buf2, 0, sizeof(buf2));

        n1 = HDread(fd1, buf1, sizeof(buf1));
        if (n1 < 0 || (size_t)n1 > sizeof(buf1))
            break;
        n2 = HDread(fd2, buf2, sizeof(buf2));
        if (n2 < 0 || (size_t)n2 > sizeof(buf2))
            break;

        if (n1 != n2)
            break;

        if (n1 == 0 && n2 == 0) {
            ret = true;
            break;
        }

        if (memcmp(buf1, buf2, (size_t)n1) != 0)
            break;

    } /* end while */

out:
    if (fd1)
        HDclose(fd1);
    if (fd2)
        HDclose(fd2);
    return ret;
} /* end files_have_same_contents() */

/*-------------------------------------------------------------------------
 * Function:    test_non_extendible
 *
 * Purpose:     Tests a non-extendible dataset with a single external file.
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_non_extendible(hid_t file)
{
    hid_t   dcpl        = H5I_INVALID_HID; /* dataset creation properties          */
    hid_t   space       = H5I_INVALID_HID; /* data space                           */
    hid_t   dset        = H5I_INVALID_HID; /* dataset                              */
    hsize_t cur_size[1] = {100};           /* data space current size              */
    hsize_t max_size[1] = {100};           /* data space maximum size              */
    int     n           = 0;               /* number of external files             */
    off_t   file_offset = 0;               /* external file offset                 */
    hsize_t file_size   = 0;               /* sizeof external file segment         */
    haddr_t dset_addr   = HADDR_UNDEF;     /* address of dataset                   */

    TESTING("fixed-size data space, exact storage");

    /* Create the dataset and close */
    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    if (H5Pset_external(dcpl, "ext1.data", 0, (hsize_t)(max_size[0] * sizeof(int))) < 0)
        FAIL_STACK_ERROR;
    if ((space = H5Screate_simple(1, cur_size, max_size)) < 0)
        FAIL_STACK_ERROR;
    if ((dset = H5Dcreate2(file, "dset1", H5T_NATIVE_INT, space, H5P_DEFAULT, dcpl, H5P_DEFAULT)) < 0)
        FAIL_STACK_ERROR;
    if (H5Dclose(dset) < 0)
        FAIL_STACK_ERROR;
    if (H5Sclose(space) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;

    /* Read dataset creation information */
    if ((dset = H5Dopen2(file, "dset1", H5P_DEFAULT)) < 0)
        FAIL_STACK_ERROR;

    /* Test dataset address.  Should be undefined. */
    H5E_BEGIN_TRY
    {
        dset_addr = H5Dget_offset(dset);
    }
    H5E_END_TRY
    if (dset_addr != HADDR_UNDEF)
        FAIL_STACK_ERROR;

    /* Check external count */
    if ((dcpl = H5Dget_create_plist(dset)) < 0)
        FAIL_STACK_ERROR;
    if ((n = H5Pget_external_count(dcpl)) < 0)
        FAIL_STACK_ERROR;
    if (1 != n) {
        H5_FAILED();
        puts("    Returned external count is wrong.");
        printf("   got: %d\n    ans: 1\n", n);
        goto error;
    }

    /* Verify external file settings */
    if (H5Pget_external(dcpl, 0, 0, NULL, &file_offset, &file_size) < 0)
        FAIL_STACK_ERROR;
    if (file_offset != 0) {
        H5_FAILED();
        puts("    Wrong file offset.");
        printf("    got: %lu\n    ans: 0\n", (unsigned long)file_offset);
        goto error;
    }
    if (file_size != (max_size[0] * sizeof(int))) {
        H5_FAILED();
        puts("    Wrong file size.");
        printf("    got: %" PRIuHSIZE "\n    ans: %" PRIuHSIZE "\n", file_size, max_size[0] * sizeof(int));
        goto error;
    }

    /* Done (dataspace was previously closed) */
    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;
    if (H5Dclose(dset) < 0)
        FAIL_STACK_ERROR;
    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Pclose(dcpl);
        H5Sclose(space);
        H5Dclose(dset);
    }
    H5E_END_TRY
    return 1;
} /* end test_non_extendible() */

/*-------------------------------------------------------------------------
 * Function:    test_too_small
 *
 * Purpose:     Test a single external file which is too small to represent
 *              all the data.
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_too_small(hid_t file)
{
    hid_t   dcpl        = H5I_INVALID_HID; /* dataset creation properties          */
    hid_t   space       = H5I_INVALID_HID; /* data space                           */
    hid_t   dset        = H5I_INVALID_HID; /* dataset                              */
    hsize_t cur_size[1] = {100};           /* current data space size              */
    hsize_t max_size[1] = {100};           /* maximum data space size              */

    TESTING("external storage is too small");

    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    if (H5Pset_external(dcpl, "ext1.data", 0, (hsize_t)(max_size[0] * sizeof(int) - 1)) < 0) /* note -1 */
        FAIL_STACK_ERROR;
    if ((space = H5Screate_simple(1, cur_size, max_size)) < 0)
        FAIL_STACK_ERROR;

    H5E_BEGIN_TRY
    {
        dset = H5Dcreate2(file, "dset2", H5T_NATIVE_INT, space, H5P_DEFAULT, dcpl, H5P_DEFAULT);
    }
    H5E_END_TRY
    if (dset >= 0)
        FAIL_PUTS_ERROR("    Small external file succeeded instead of failing.");
    if (H5Sclose(space) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;

    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Sclose(space);
        H5Pclose(dcpl);
        H5Dclose(dset);
    }
    H5E_END_TRY
    return 1;
} /* end test_too_small() */

/*-------------------------------------------------------------------------
 * Function:    test_large_enough_current_eventual
 *
 * Purpose:     Test a single external file which is large enough to
 *              represent the current data and large enough to represent the
 *              eventual size of the data.
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_large_enough_current_eventual(hid_t file)
{
    hid_t   dcpl        = H5I_INVALID_HID; /* dataset creation properties          */
    hid_t   space       = H5I_INVALID_HID; /* data space                           */
    hid_t   dset        = H5I_INVALID_HID; /* dataset                              */
    hsize_t cur_size[1] = {100};           /* current data space size              */
    hsize_t max_size[1] = {200};           /* maximum data space size              */

    TESTING("extendible dataspace, exact external size");

    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    if (H5Pset_external(dcpl, "ext1.data", 0, (hsize_t)(max_size[0] * sizeof(int))) < 0)
        FAIL_STACK_ERROR;
    if ((space = H5Screate_simple(1, cur_size, max_size)) < 0)
        FAIL_STACK_ERROR;
    if ((dset = H5Dcreate2(file, "dset3", H5T_NATIVE_INT, space, H5P_DEFAULT, dcpl, H5P_DEFAULT)) < 0)
        FAIL_STACK_ERROR;

    if (H5Dclose(dset) < 0)
        FAIL_STACK_ERROR;
    if (H5Sclose(space) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;

    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Dclose(dset);
        H5Pclose(dcpl);
        H5Sclose(space);
    }
    H5E_END_TRY
    return 1;
} /* end test_large_enough_current_eventual() */

/*-------------------------------------------------------------------------
 * Function:    test_large_enough_current_not_eventual
 *
 * Purpose:     Test a single external file which is large enough for the
 *              current data size but not large enough for the eventual size.
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_large_enough_current_not_eventual(hid_t file)
{
    hid_t   dcpl        = H5I_INVALID_HID; /* dataset creation properties          */
    hid_t   space       = H5I_INVALID_HID; /* data space                           */
    hid_t   dset        = H5I_INVALID_HID; /* dataset                              */
    hsize_t cur_size[1] = {100};           /* current data space size              */
    hsize_t max_size[1] = {200};           /* maximum data space size              */

    TESTING("extendible dataspace, external storage is too small");

    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    if (H5Pset_external(dcpl, "ext1.data", 0, (hsize_t)(max_size[0] * sizeof(int) - 1)) < 0) /* note -1 */
        FAIL_STACK_ERROR;
    if ((space = H5Screate_simple(1, cur_size, max_size)) < 0)
        FAIL_STACK_ERROR;

    H5E_BEGIN_TRY
    {
        dset = H5Dcreate2(file, "dset4", H5T_NATIVE_INT, space, H5P_DEFAULT, dcpl, H5P_DEFAULT);
    }
    H5E_END_TRY
    if (dset >= 0)
        FAIL_PUTS_ERROR("    Small external file succeeded instead of failing.");

    if (H5Sclose(space) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;

    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Dclose(dset);
        H5Pclose(dcpl);
        H5Sclose(space);
    }
    H5E_END_TRY
    return 1;
} /* end test_large_enough_current_not_eventual() */

/*-------------------------------------------------------------------------
 * Function:    test_unlimited
 *
 * Purpose:     Test a single external file of unlimited size and an
 *              unlimited data space.
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_unlimited(hid_t file)
{
    hid_t   dcpl        = H5I_INVALID_HID; /* dataset creation properties   */
    hid_t   space       = H5I_INVALID_HID; /* data space                    */
    hid_t   dset        = H5I_INVALID_HID; /* dataset                       */
    hsize_t cur_size[1] = {100};           /* data space current size       */
    hsize_t max_size[1] = {H5S_UNLIMITED}; /* data space maximum size       */
    int     n;                             /* number of external files      */
    off_t   file_offset;                   /* external file offset          */
    hsize_t file_size;                     /* sizeof external file segment  */

    TESTING("unlimited dataspace, unlimited external storage");

    /* Create dataset */
    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    if (H5Pset_external(dcpl, "ext1.data", 0, H5F_UNLIMITED) < 0)
        FAIL_STACK_ERROR;
    if ((space = H5Screate_simple(1, cur_size, max_size)) < 0)
        FAIL_STACK_ERROR;
    if ((dset = H5Dcreate2(file, "dset5", H5T_NATIVE_INT, space, H5P_DEFAULT, dcpl, H5P_DEFAULT)) < 0)
        FAIL_STACK_ERROR;

    if (H5Dclose(dset) < 0)
        FAIL_STACK_ERROR;
    if (H5Sclose(space) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;

    /* Read dataset creation information */
    if ((dset = H5Dopen2(file, "dset5", H5P_DEFAULT)) < 0)
        FAIL_STACK_ERROR;
    if ((dcpl = H5Dget_create_plist(dset)) < 0)
        FAIL_STACK_ERROR;
    if ((n = H5Pget_external_count(dcpl)) < 0)
        FAIL_STACK_ERROR;
    if (1 != n) {
        H5_FAILED();
        puts("    Returned external count is wrong.");
        printf("    got: %d\n    ans: 1\n", n);
        goto error;
    } /* end if */

    if (H5Pget_external(dcpl, 0, 0, NULL, &file_offset, &file_size) < 0)
        FAIL_STACK_ERROR;
    if (file_offset != 0) {
        H5_FAILED();
        puts("    Wrong file offset.");
        printf("    got: %lu\n    ans: 0\n", (unsigned long)file_offset);
        goto error;
    }
    if (H5F_UNLIMITED != file_size) {
        H5_FAILED();
        puts("    Wrong file size.");
        printf("    got: %lu\n    ans: INF\n", (unsigned long)file_size);
        goto error;
    }

    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;
    if (H5Dclose(dset) < 0)
        FAIL_STACK_ERROR;

    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Dclose(dset);
        H5Pclose(dcpl);
        H5Sclose(space);
    }
    H5E_END_TRY
    return 1;
} /* end test_unlimited() */

/*-------------------------------------------------------------------------
 * Function:    __add_external_files
 *
 * Purpose:     Add external file names to the DCPL with the given properties.
 *              Used in test_multiple_files().
 *              Limit to no more than 999 external files.
 *
 * Return:      Success:    0
 *              Failure:    -1
 *
 *-------------------------------------------------------------------------
 */
static int
add_external_files(hid_t dcpl_id, unsigned int n_external_files, off_t offset, hsize_t max_ext_size)
{
    char         exname[AEF_EXNAME_MAX_LEN + 1];
    unsigned int i = 0;

    if (dcpl_id < 0) {
        return -1;
    }
    for (i = 0; i < n_external_files; i++) {
        if (snprintf(exname, AEF_EXNAME_MAX_LEN, "ext%d.data", i + 1) > AEF_EXNAME_MAX_LEN) {
            fprintf(stderr, "External file %d overflows name buffer\n", i + 1);
            fflush(stderr);
            return -1;
        }
        if (H5Pset_external(dcpl_id, exname, offset, max_ext_size) < 0) {
            fprintf(stderr, "Problem adding external file %s\n", exname);
            fflush(stderr);
            return -1;
        }
    }
    return 0;
} /* end __add_external_files() */

/*-------------------------------------------------------------------------
 * Function:    test_multiple_files
 *
 * Purpose:     Test multiple external files for a dataset.
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_multiple_files(hid_t file)
{
    hid_t        dcpl        = H5I_INVALID_HID; /* dataset creation properties         */
    hid_t        space       = H5I_INVALID_HID; /* dataspace                           */
    hid_t        dset        = H5I_INVALID_HID; /* dataset                             */
    hsize_t      cur_size[1] = {100};           /* data space current size             */
    hsize_t      max_size[1] = {100};           /* data space maximum size             */
    hsize_t      max_ext_size;                  /* maximum size of external files      */
    unsigned int n_external_files = 4;

    TESTING("multiple external files");

    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;

    max_ext_size = (hsize_t)(sizeof(int) * max_size[0] / n_external_files);

    if (add_external_files(dcpl, n_external_files, 0, max_ext_size) < 0) {
        FAIL_STACK_ERROR;
    }

    if ((space = H5Screate_simple(1, cur_size, max_size)) < 0)
        FAIL_STACK_ERROR;

    if ((dset = H5Dcreate2(file, "dset6", H5T_NATIVE_INT, space, H5P_DEFAULT, dcpl, H5P_DEFAULT)) < 0)
        FAIL_STACK_ERROR;

    if (H5Dclose(dset) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;
    /* Reuse space below */

    /* ----------------------------------------------
     * Verify that too-small external files will fail
     */
    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;

    max_ext_size -= 1;

    if (add_external_files(dcpl, n_external_files, 0, max_ext_size) < 0) {
        FAIL_STACK_ERROR;
    }

    H5E_BEGIN_TRY
    {
        dset = H5Dcreate2(file, "dset7", H5T_NATIVE_INT, space, H5P_DEFAULT, dcpl, H5P_DEFAULT);
    }
    H5E_END_TRY
    if (dset >= 0)
        FAIL_PUTS_ERROR("    Small external files succeeded instead of failing.");

    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;
    if (H5Sclose(space) < 0)
        FAIL_STACK_ERROR;

    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Dclose(dset);
        H5Pclose(dcpl);
        H5Sclose(space);
    }
    H5E_END_TRY
    return 1;
} /* end test_multiple_files() */

/*-------------------------------------------------------------------------
 * Function:    test_add_to_unlimited
 *
 * Purpose:     It should be impossible to define an unlimited external file
 *              and then follow it with another external file.
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_add_to_unlimited(void)
{
    hid_t  dcpl   = H5I_INVALID_HID; /* dataset creation properties          */
    herr_t status = FAIL;            /* function return status               */
    int    n      = 0;               /* number of external files             */

    TESTING("external file following unlimited file");

    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    if (H5Pset_external(dcpl, "ext1.data", 0, H5F_UNLIMITED) < 0)
        FAIL_STACK_ERROR;

    H5E_BEGIN_TRY
    {
        status = H5Pset_external(dcpl, "ext2.data", 0, 100);
    }
    H5E_END_TRY
    if (status >= 0)
        FAIL_PUTS_ERROR("    H5Pset_external() succeeded when it should have failed.");

    if ((n = H5Pget_external_count(dcpl)) < 0)
        FAIL_STACK_ERROR;
    if (1 != n)
        FAIL_PUTS_ERROR("    Wrong external file count returned.");

    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;
    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Pclose(dcpl);
    }
    H5E_END_TRY
    return 1;
} /* end test_add_to_unlimited() */

/*-------------------------------------------------------------------------
 * Function:    test_overflow
 *
 * Purpose:     It should be impossible to create a set of external files
 *              whose total size overflows a size_t integer.
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_overflow(void)
{
    hid_t  dcpl   = H5I_INVALID_HID; /* dataset creation properties          */
    herr_t status = FAIL;            /* return status                        */

    TESTING("address overflow in external files");

    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    if (H5Pset_external(dcpl, "ext1.data", 0, H5F_UNLIMITED - 1) < 0)
        FAIL_STACK_ERROR;

    H5E_BEGIN_TRY
    {
        status = H5Pset_external(dcpl, "ext2.data", 0, 100);
    }
    H5E_END_TRY
    if (status >= 0)
        FAIL_PUTS_ERROR("    H5Pset_external() succeeded when it should have failed.");

    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;

    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Pclose(dcpl);
    }
    H5E_END_TRY
    return 1;
} /* end test_overflow() */

/*-------------------------------------------------------------------------
 * Function:    test_read_file_set
 *
 * Purpose:     Tests reading from an external file set.
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_read_file_set(hid_t fapl)
{
    hid_t   file  = H5I_INVALID_HID;    /* file to write to                     */
    hid_t   dcpl  = H5I_INVALID_HID;    /* dataset creation properties          */
    hid_t   space = H5I_INVALID_HID;    /* data space                           */
    hid_t   dset  = H5I_INVALID_HID;    /* dataset                              */
    hid_t   grp   = H5I_INVALID_HID;    /* group to emit diagnostics            */
    size_t  i     = 0;                  /* miscellaneous counter                */
    char    filename[1024];             /* file names                           */
    int     part[PART_SIZE];            /* raw data buffer (partial)            */
    int     whole[TOTAL_SIZE];          /* raw data buffer (total)              */
    hsize_t cur_size;                   /* current data space size              */
    hid_t   hs_space = H5I_INVALID_HID; /* hyperslab data space                 */
    hsize_t hs_start = 30;              /* hyperslab starting offset            */
    hsize_t hs_count = 25;              /* hyperslab size                       */

    TESTING("read external dataset");

    if (HDsetenv("HDF5_EXTFILE_PREFIX", "", 1) < 0)
        TEST_ERROR;

    /* Reset the raw data files */
    if (reset_raw_data_files(false) < 0)
        TEST_ERROR;

    /* Create the file and an initial group.  This causes messages about
     * debugging to be emitted before we start playing games with what the
     * output looks like.
     */
    h5_fixname(EXT_FNAME[1], fapl, filename, sizeof(filename));
    if ((file = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl)) < 0)
        FAIL_STACK_ERROR;
    if ((grp = H5Gcreate2(file, "emit-diagnostics", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0)
        FAIL_STACK_ERROR;
    if (H5Gclose(grp) < 0)
        FAIL_STACK_ERROR;

    /* Create the dcpl */
    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    for (i = 0; i < N_EXT_FILES; i++) {
        snprintf(filename, sizeof(filename), "extern_%dr.raw", (int)i + 1);
        if (H5Pset_external(dcpl, filename, (off_t)(i * GARBAGE_PER_FILE), (hsize_t)sizeof(part)) < 0)
            FAIL_STACK_ERROR;
    }

    /* Create the dataspace */
    cur_size = TOTAL_SIZE;
    if ((space = H5Screate_simple(1, &cur_size, NULL)) < 0)
        FAIL_STACK_ERROR;

    /* Create the dataset */
    if ((dset = H5Dcreate2(file, "dset1", H5T_NATIVE_INT, space, H5P_DEFAULT, dcpl, H5P_DEFAULT)) < 0)
        FAIL_STACK_ERROR;

    /* Read the entire dataset */
    memset(whole, 0, sizeof(whole));
    if (H5Dread(dset, H5T_NATIVE_INT, space, space, H5P_DEFAULT, whole) < 0)
        FAIL_STACK_ERROR;

    /* Compare data */
    for (i = 0; i < TOTAL_SIZE; i++)
        if (whole[i] != (signed)i)
            FAIL_PUTS_ERROR("Incorrect value(s) read.");

    /* Read via a hypserslab in the middle of the dataset */

    /* Set up dataspace */
    if ((hs_space = H5Scopy(space)) < 0)
        FAIL_STACK_ERROR;
    if (H5Sselect_hyperslab(hs_space, H5S_SELECT_SET, &hs_start, NULL, &hs_count, NULL) < 0)
        FAIL_STACK_ERROR;

    /* Read */
    memset(whole, 0, sizeof(whole));
    if (H5Dread(dset, H5T_NATIVE_INT, hs_space, hs_space, H5P_DEFAULT, whole) < 0)
        FAIL_STACK_ERROR;

    /* Verify data */
    for (i = (size_t)hs_start; i < (size_t)(hs_start + hs_count); i++) {
        if (whole[i] != (signed)i)
            FAIL_PUTS_ERROR("Incorrect value(s) read (hyperslab).");
    } /* end for */

    if (H5Dclose(dset) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;
    if (H5Sclose(space) < 0)
        FAIL_STACK_ERROR;
    if (H5Sclose(hs_space) < 0)
        FAIL_STACK_ERROR;
    if (H5Fclose(file) < 0)
        FAIL_STACK_ERROR;
    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Gclose(grp);
        H5Dclose(dset);
        H5Pclose(dcpl);
        H5Sclose(space);
        H5Sclose(hs_space);
        H5Fclose(file);
    }
    H5E_END_TRY
    return 1;
} /* end test_read_file_set() */

/*-------------------------------------------------------------------------
 * Function:    test_write_file_set
 *
 * Purpose:     Tests writing to an external file set.
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_write_file_set(hid_t fapl)
{
    hid_t    file       = H5I_INVALID_HID; /* file to which to write               */
    hid_t    dcpl       = H5I_INVALID_HID; /* dataset creation properties          */
    hid_t    mem_space  = H5I_INVALID_HID; /* memory data space                    */
    hid_t    file_space = H5I_INVALID_HID; /* file data space                      */
    hid_t    dset       = H5I_INVALID_HID; /* dataset                              */
    unsigned i          = 0;               /* miscellaneous counter                */
    int      part[PART_SIZE];              /* raw data buffer (partial)            */
    int      whole[TOTAL_SIZE];            /* raw data buffer (total)              */
    hsize_t  cur_size = 100;               /* current data space size              */
    hsize_t  max_size = 200;               /* maximum data space size              */
    hsize_t  hs_start = 100;               /* hyperslab starting offset            */
    hsize_t  hs_count = 100;               /* hyperslab size                       */
    char     filename[1024];               /* file name                            */

    TESTING("write external dataset");

    if (HDsetenv("HDF5_EXTFILE_PREFIX", "", 1) < 0)
        TEST_ERROR;

    /* Create another file */
    h5_fixname(EXT_FNAME[2], fapl, filename, sizeof(filename));
    if ((file = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl)) < 0)
        FAIL_STACK_ERROR;

    /* Create the dcpl and external file list */
    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    for (i = 0; i < N_EXT_FILES; i++) {
        hsize_t size;

        snprintf(filename, sizeof(filename), "extern_%dw.raw", (int)i + 1);

        if (i != N_EXT_FILES - 1)
            size = (hsize_t)sizeof(part);
        else
            size = H5F_UNLIMITED;

        if (H5Pset_external(dcpl, filename, (off_t)(i * GARBAGE_PER_FILE), size) < 0)
            FAIL_STACK_ERROR;
    } /* end for */

    /* Reset the raw data files */
    if (reset_raw_data_files(false) < 0)
        TEST_ERROR;

    /* Create the dataset */
    if ((mem_space = H5Screate_simple(1, &cur_size, &max_size)) < 0)
        FAIL_STACK_ERROR;
    if ((file_space = H5Scopy(mem_space)) < 0)
        FAIL_STACK_ERROR;
    if ((dset = H5Dcreate2(file, "dset1", H5T_NATIVE_INT, file_space, H5P_DEFAULT, dcpl, H5P_DEFAULT)) < 0)
        FAIL_STACK_ERROR;

    /* Write the entire dataset and compare with the original */
    for (i = 0; i < cur_size; i++)
        whole[i] = (int)i;
    if (H5Dwrite(dset, H5T_NATIVE_INT, mem_space, file_space, H5P_DEFAULT, whole) < 0)
        FAIL_STACK_ERROR;
    for (i = 0; i < N_EXT_FILES; i++) {
        char name1[64], name2[64];

        snprintf(name1, sizeof(name1), "extern_%dr.raw", i + 1);
        snprintf(name2, sizeof(name2), "extern_%dw.raw", i + 1);
        if (!files_have_same_contents(name1, name2))
            FAIL_PUTS_ERROR("   Output differs from expected value.");
    } /* end for */

    /* Extend the dataset by another 100 elements */
    if (H5Dset_extent(dset, &max_size) < 0)
        FAIL_STACK_ERROR;
    if (H5Sclose(file_space) < 0)
        FAIL_STACK_ERROR;
    if ((file_space = H5Dget_space(dset)) < 0)
        FAIL_STACK_ERROR;

    /* Write second half of dataset */
    for (i = 0; i < hs_count; i++)
        whole[i] = 100 + (int)i;
    if (H5Sselect_hyperslab(file_space, H5S_SELECT_SET, &hs_start, NULL, &hs_count, NULL) < 0)
        FAIL_STACK_ERROR;
    if (H5Dwrite(dset, H5T_NATIVE_INT, mem_space, file_space, H5P_DEFAULT, whole) < 0)
        FAIL_STACK_ERROR;

    if (H5Dclose(dset) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;
    if (H5Sclose(mem_space) < 0)
        FAIL_STACK_ERROR;
    if (H5Sclose(file_space) < 0)
        FAIL_STACK_ERROR;
    if (H5Fclose(file) < 0)
        FAIL_STACK_ERROR;

    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Dclose(dset);
        H5Pclose(dcpl);
        H5Sclose(mem_space);
        H5Sclose(file_space);
        H5Fclose(file);
    }
    H5E_END_TRY
    return 1;
} /* end test_write_file_set() */

/*-------------------------------------------------------------------------
 * Function:    test_path_absolute
 *
 * Purpose:     Test absolute filenames for external files.
 *              This will create an HDF5 file in a subdirectory which will
 *              refer to /full/path/extern_*a.raw on unix and to
 *              c:\full\path\extern_*a.raw and \full\path\extern_*a.raw on
 *              windows.
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_path_absolute(hid_t fapl)
{
    hid_t   file  = H5I_INVALID_HID; /* file to write to                     */
    hid_t   dcpl  = H5I_INVALID_HID; /* dataset creation properties          */
    hid_t   space = H5I_INVALID_HID; /* data space                           */
    hid_t   dset  = H5I_INVALID_HID; /* dataset                              */
    size_t  i     = 0;               /* miscellaneous counter                */
    char    cwdpath[1024];           /* working directory                    */
    char    filename[1088];          /* file name                            */
    int     part[PART_SIZE];         /* raw data buffer (partial)            */
    int     whole[TOTAL_SIZE];       /* raw data buffer (total)              */
    hsize_t cur_size;                /* current data space size              */

    TESTING("absolute filenames for external file");

    h5_fixname(EXT_FNAME[3], fapl, filename, sizeof(filename));
    if ((file = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl)) < 0)
        FAIL_STACK_ERROR;

    /* Reset the raw data files */
    if (reset_raw_data_files(false) < 0)
        TEST_ERROR;

    /* Create the dcpl */
    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    if (NULL == HDgetcwd(cwdpath, sizeof(cwdpath)))
        TEST_ERROR;
    for (i = 0; i < N_EXT_FILES; i++) {
        snprintf(filename, sizeof(filename), "%s%sextern_%zur.raw", cwdpath, H5_DIR_SEPS, i + 1);
#if defined(H5_HAVE_WINDOW_PATH)
        /* For windows, test path-absolute case (\dir\file.raw) for the second file */
        if (i == 1)
            snprintf(filename, sizeof(filename), "%s%sextern_%zur.raw", cwdpath + 2, H5_DIR_SEPS, i + 1);
#endif
        if (H5Pset_external(dcpl, filename, (off_t)(i * GARBAGE_PER_FILE), (hsize_t)sizeof(part)) < 0)
            FAIL_STACK_ERROR;
    } /* end for */

    /* create the dataspace */
    cur_size = TOTAL_SIZE;
    if ((space = H5Screate_simple(1, &cur_size, NULL)) < 0)
        FAIL_STACK_ERROR;

    /* create the dataset */
    if ((dset = H5Dcreate2(file, "dset1", H5T_NATIVE_INT, space, H5P_DEFAULT, dcpl, H5P_DEFAULT)) < 0)
        FAIL_STACK_ERROR;

    /* Read the entire dataset and compare with the original */
    memset(whole, 0, sizeof(whole));
    if (H5Dread(dset, H5T_NATIVE_INT, space, space, H5P_DEFAULT, whole) < 0)
        FAIL_STACK_ERROR;
    for (i = 0; i < TOTAL_SIZE; i++)
        if (whole[i] != (signed)i)
            FAIL_PUTS_ERROR("Incorrect value(s) read.");

    if (H5Dclose(dset) < 0)
        FAIL_STACK_ERROR;
    if (H5Sclose(space) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;
    if (H5Fclose(file) < 0)
        FAIL_STACK_ERROR;
    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Dclose(dset);
        H5Sclose(space);
        H5Pclose(dcpl);
        H5Fclose(file);
    }
    H5E_END_TRY
    return 1;
} /* end test_path_absolute() */

/*-------------------------------------------------------------------------
 * Function:    test_path_relative
 *
 * Purpose:     Test external files with filename relative to current directory.
 *              This will create an HDF5 file in a subdirectory which will
 *              refer to extern_*a.raw
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_path_relative(hid_t fapl)
{
    hid_t   file  = H5I_INVALID_HID; /* file to write to                     */
    hid_t   dcpl  = H5I_INVALID_HID; /* dataset creation properties          */
    hid_t   space = H5I_INVALID_HID; /* data space                           */
    hid_t   dset  = H5I_INVALID_HID; /* dataset                              */
    size_t  i     = 0;               /* miscellaneous counters               */
    char    filename[1024];          /* file name                            */
    int     part[PART_SIZE];         /* raw data buffer (partial)            */
    int     whole[TOTAL_SIZE];       /* raw data buffer (total)              */
    hsize_t cur_size;                /* current data space size              */

    TESTING("filenames relative to current directory for external file");

    if (HDsetenv("HDF5_EXTFILE_PREFIX", "", 1) < 0)
        TEST_ERROR;

    if (HDmkdir("extern_dir", (mode_t)0755) < 0 && errno != EEXIST)
        TEST_ERROR;

    h5_fixname(EXT_FNAME[4], fapl, filename, sizeof(filename));
    if ((file = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl)) < 0)
        FAIL_STACK_ERROR;

    /* Reset the raw data files */
    if (reset_raw_data_files(false) < 0)
        TEST_ERROR;

    /* Create the dataset */
    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    for (i = 0; i < N_EXT_FILES; i++) {
        snprintf(filename, sizeof(filename), "extern_%dr.raw", (int)i + 1);
        if (H5Pset_external(dcpl, filename, (off_t)(i * GARBAGE_PER_FILE), (hsize_t)sizeof(part)) < 0)
            FAIL_STACK_ERROR;
    } /* end for */

    cur_size = TOTAL_SIZE;
    if ((space = H5Screate_simple(1, &cur_size, NULL)) < 0)
        FAIL_STACK_ERROR;
    if ((dset = H5Dcreate2(file, "dset1", H5T_NATIVE_INT, space, H5P_DEFAULT, dcpl, H5P_DEFAULT)) < 0)
        FAIL_STACK_ERROR;

    /* Read the entire dataset and compare with the original */
    memset(whole, 0, sizeof(whole));
    if (H5Dread(dset, H5T_NATIVE_INT, space, space, H5P_DEFAULT, whole) < 0)
        FAIL_STACK_ERROR;
    for (i = 0; i < TOTAL_SIZE; i++)
        if (whole[i] != (signed)i)
            FAIL_PUTS_ERROR("Incorrect value(s) read.");

    if (H5Dclose(dset) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;
    if (H5Sclose(space) < 0)
        FAIL_STACK_ERROR;
    if (H5Fclose(file) < 0)
        FAIL_STACK_ERROR;
    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Dclose(dset);
        H5Pclose(dcpl);
        H5Sclose(space);
        H5Fclose(file);
    }
    H5E_END_TRY
    return 1;
} /* end test_path_relative() */

/*-------------------------------------------------------------------------
 * Function:    test_path_relative_cwd
 *
 * Purpose:     Test external files with filename relative to current directory.
 *              This will create an HDF5 file in a subdirectory which will
 *              refer to ../extern_*a.raw
 *              The files are then accessed by setting the efile_prefix dataset
 *              access property to "${ORIGIN}".
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_path_relative_cwd(hid_t fapl)
{
    hid_t   file  = H5I_INVALID_HID; /* file to write to                     */
    hid_t   dcpl  = H5I_INVALID_HID; /* dataset creation properties          */
    hid_t   space = H5I_INVALID_HID; /* data space                           */
    hid_t   dapl  = H5I_INVALID_HID; /* dataset access property list         */
    hid_t   dapl2 = H5I_INVALID_HID; /* copy of dapl                         */
    hid_t   dset  = H5I_INVALID_HID; /* dataset                              */
    hid_t   dset2 = H5I_INVALID_HID; /* dataset, opened a second time        */
    hid_t   dset3 = H5I_INVALID_HID; /* dataset, opened with different prefix    */
    size_t  i     = 0;               /* miscellaneous counters               */
    char    filename[1024];          /* file name                            */
    int     part[PART_SIZE];         /* raw data buffer (partial)            */
    int     whole[TOTAL_SIZE];       /* raw data buffer (total)              */
    hsize_t cur_size;                /* current data space size              */
    char    buffer[1024];            /* buffer to read efile_prefix          */

    TESTING("filenames relative to HDF5 file for external file");

    if (HDsetenv("HDF5_EXTFILE_PREFIX", "", 1) < 0)
        TEST_ERROR;

    if (HDmkdir("extern_dir", (mode_t)0755) < 0 && errno != EEXIST)
        TEST_ERROR;

    h5_fixname(EXT_FNAME[4], fapl, filename, sizeof(filename));
    if ((file = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl)) < 0)
        FAIL_STACK_ERROR;

    /* Reset the raw data files */
    if (reset_raw_data_files(false) < 0)
        TEST_ERROR;

    /* Create the dataset */
    if ((dcpl = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    for (i = 0; i < N_EXT_FILES; i++) {
        snprintf(filename, sizeof(filename), "..%sextern_%dr.raw", H5_DIR_SEPS, (int)i + 1);
        if (H5Pset_external(dcpl, filename, (off_t)(i * GARBAGE_PER_FILE), (hsize_t)sizeof(part)) < 0)
            FAIL_STACK_ERROR;
    } /* end for */

    cur_size = TOTAL_SIZE;
    if ((space = H5Screate_simple(1, &cur_size, NULL)) < 0)
        FAIL_STACK_ERROR;
    if ((dapl = H5Pcreate(H5P_DATASET_ACCESS)) < 0)
        FAIL_STACK_ERROR;
    if (H5Pset_efile_prefix(dapl, "${ORIGIN}") < 0)
        FAIL_STACK_ERROR;
    if (H5Pget_efile_prefix(dapl, buffer, sizeof(buffer)) < 0)
        FAIL_STACK_ERROR;
    if (strcmp(buffer, "${ORIGIN}") != 0)
        FAIL_PUTS_ERROR("efile prefix not set correctly");
    if ((dapl2 = H5Pcopy(dapl)) < 0)
        FAIL_STACK_ERROR;

    /* Create dataset */
    if ((dset = H5Dcreate2(file, "dset1", H5T_NATIVE_INT, space, H5P_DEFAULT, dcpl, dapl2)) < 0)
        FAIL_STACK_ERROR;

    /* Reopen dataset with same efile_prefix property */
    if ((dset2 = H5Dopen2(file, "dset1", dapl2)) < 0)
        FAIL_STACK_ERROR;

    /* Reopen dataset with different efile_prefix property */
    if (H5Pset_efile_prefix(dapl, "//") < 0)
        FAIL_STACK_ERROR;
    H5E_BEGIN_TRY
    {
        dset3 = H5Dopen2(file, "dset1", dapl);
    }
    H5E_END_TRY
    if (dset3 >= 0)
        FAIL_PUTS_ERROR("reopening the dataset with a different efile_prefix succeeded");

    /* Read the entire dataset and compare with the original */
    memset(whole, 0, sizeof(whole));
    if (H5Dread(dset, H5T_NATIVE_INT, space, space, H5P_DEFAULT, whole) < 0)
        FAIL_STACK_ERROR;
    for (i = 0; i < TOTAL_SIZE; i++)
        if (whole[i] != (signed)i)
            FAIL_PUTS_ERROR("Incorrect value(s) read.");

    /* Close dataset */
    if (H5Dclose(dset2) < 0)
        FAIL_STACK_ERROR;
    if (H5Dclose(dset) < 0)
        FAIL_STACK_ERROR;

    /* Open dataset (use a different prefix than for create.
     * This works because the dataset was closed.
     */
    if (H5Pset_efile_prefix(dapl2, "${ORIGIN}/.") < 0)
        FAIL_STACK_ERROR;
    if ((dset = H5Dopen2(file, "dset1", dapl2)) < 0)
        FAIL_STACK_ERROR;

    /* Reopen dataset with same efile_prefix property */
    if ((dset2 = H5Dopen2(file, "dset1", dapl2)) < 0)
        FAIL_STACK_ERROR;

    /* Reopen dataset with different efile_prefix property */
    if (H5Pset_efile_prefix(dapl, NULL) < 0)
        FAIL_STACK_ERROR;
    H5E_BEGIN_TRY
    {
        dset3 = H5Dopen2(file, "dset1", dapl);
    }
    H5E_END_TRY
    if (dset3 >= 0)
        FAIL_PUTS_ERROR("reopening the dataset with a different efile_prefix succeeded");

    /* Read the entire dataset and compare with the original */
    memset(whole, 0, sizeof(whole));
    if (H5Dread(dset, H5T_NATIVE_INT, space, space, H5P_DEFAULT, whole) < 0)
        FAIL_STACK_ERROR;
    for (i = 0; i < TOTAL_SIZE; i++)
        if (whole[i] != (signed)i)
            FAIL_PUTS_ERROR("Incorrect value(s) read.");

    if (H5Dclose(dset2) < 0)
        FAIL_STACK_ERROR;
    if (H5Dclose(dset) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dapl2) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dapl) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dcpl) < 0)
        FAIL_STACK_ERROR;
    if (H5Sclose(space) < 0)
        FAIL_STACK_ERROR;
    if (H5Fclose(file) < 0)
        FAIL_STACK_ERROR;
    PASSED();
    return 0;

error:
    H5E_BEGIN_TRY
    {
        H5Pclose(dapl2);
        H5Pclose(dapl);
        H5Dclose(dset3);
        H5Dclose(dset2);
        H5Dclose(dset);
        H5Pclose(dcpl);
        H5Sclose(space);
        H5Fclose(file);
    }
    H5E_END_TRY
    return 1;
} /* end test_path_relative_cwd() */

/*-------------------------------------------------------------------------
 * Function:    test_h5d_get_access_plist
 *
 * Purpose:     Ensure that H5Dget_access_plist returns correct values.
 *
 * Return:      Success:    0
 *              Failure:    1
 *
 *-------------------------------------------------------------------------
 */
static int
test_h5d_get_access_plist(hid_t fapl_id)
{
    hid_t   fid     = H5I_INVALID_HID; /* file to write to                     */
    hid_t   dcpl_id = H5I_INVALID_HID; /* dataset creation properties          */
    hid_t   dapl_id = H5I_INVALID_HID; /* dataset access properties            */
    hid_t   sid     = H5I_INVALID_HID; /* data space                           */
    hid_t   did     = H5I_INVALID_HID; /* dataset                              */
    hsize_t dims    = 0;               /* dataset size                         */
    char   *buffer  = NULL;            /* saved prefix name from dapl          */
    char    filename[1024];            /* file names                           */

    TESTING("H5Dget_access_plist() returns correct prefix");

    if (HDsetenv("HDF5_EXTFILE_PREFIX", "", 1) < 0)
        TEST_ERROR;

    /* Reset the raw data files */
    if (reset_raw_data_files(false) < 0)
        TEST_ERROR;

    /* Create the file */
    h5_fixname(EXT_FNAME[5], fapl_id, filename, sizeof(filename));
    if ((fid = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl_id)) < 0)
        FAIL_STACK_ERROR;

    /* Create the dcpl and set external storage */
    if ((dcpl_id = H5Pcreate(H5P_DATASET_CREATE)) < 0)
        FAIL_STACK_ERROR;
    if (H5Pset_external(dcpl_id, "extern_1r.raw", 0, 0) < 0)
        FAIL_STACK_ERROR;

    /* Create the dapl and set the prefix */
    if ((dapl_id = H5Pcreate(H5P_DATASET_ACCESS)) < 0)
        FAIL_STACK_ERROR;
    if (H5Pset_efile_prefix(dapl_id, "someprefix") < 0)
        FAIL_STACK_ERROR;

    /* Create the dataset */
    if ((sid = H5Screate_simple(1, &dims, NULL)) < 0)
        FAIL_STACK_ERROR;
    if ((did = H5Dcreate2(fid, "dset1", H5T_NATIVE_INT, sid, H5P_DEFAULT, dcpl_id, dapl_id)) < 0)
        FAIL_STACK_ERROR;

    /* Close the dapl */
    if (H5Pclose(dapl_id) < 0)
        FAIL_STACK_ERROR;
    dapl_id = -1;

    /* Get a data access property list from the dataset */
    if ((dapl_id = H5Dget_access_plist(did)) < 0)
        FAIL_STACK_ERROR;

    /* Check the value for the external prefix */
    if ((buffer = (char *)calloc((size_t)64, sizeof(char))) == NULL)
        TEST_ERROR;
    if (H5Pget_efile_prefix(dapl_id, buffer, (size_t)64) < 0)
        FAIL_STACK_ERROR;
    if (strcmp(buffer, "someprefix") != 0)
        FAIL_PUTS_ERROR("external file prefix from dapl incorrect");

    /* Close everything */
    free(buffer);
    if (H5Sclose(sid) < 0)
        FAIL_STACK_ERROR;
    if (H5Dclose(did) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dcpl_id) < 0)
        FAIL_STACK_ERROR;
    if (H5Pclose(dapl_id) < 0)
        FAIL_STACK_ERROR;
    if (H5Fclose(fid) < 0)
        FAIL_STACK_ERROR;

    PASSED();
    return 0;

error:
    if (buffer)
        free(buffer);
    H5E_BEGIN_TRY
    {
        H5Dclose(did);
        H5Pclose(dcpl_id);
        H5Pclose(dapl_id);
        H5Sclose(sid);
        H5Fclose(fid);
    }
    H5E_END_TRY
    return 1;
} /* end test_h5d_get_access_plist() */

/*-------------------------------------------------------------------------
 * Function:    main
 *
 * Purpose:     Runs external dataset tests.
 *
 * Return:      EXIT_SUCCESS/EXIT_FAILURE
 *
 *-------------------------------------------------------------------------
 */
int
main(void)
{
    hid_t    fapl_id_old = H5I_INVALID_HID; /* file access properties (old format)  */
    hid_t    fapl_id_new = H5I_INVALID_HID; /* file access properties (new format)  */
    hid_t    fid         = H5I_INVALID_HID; /* file for test_1* functions           */
    hid_t    gid         = H5I_INVALID_HID; /* group to emit diagnostics            */
    char     filename[1024];                /* file name for test_1* funcs          */
    unsigned latest_format;                 /* default or latest file format        */
    int      nerrors = 0;                   /* number of errors                     */

    h5_reset();

    /* Get a fapl for the old (default) file format */
    fapl_id_old = h5_fileaccess();
    h5_fixname(EXT_FNAME[0], fapl_id_old, filename, sizeof(filename));

    /* Copy and set up a fapl for the latest file format */
    if ((fapl_id_new = H5Pcopy(fapl_id_old)) < 0)
        FAIL_STACK_ERROR;
    if (H5Pset_libver_bounds(fapl_id_new, H5F_LIBVER_LATEST, H5F_LIBVER_LATEST) < 0)
        FAIL_STACK_ERROR;

    /* The file format doesn't matter for this test */
    nerrors += test_h5d_get_access_plist(fapl_id_new);
    puts("");

    /* Test with old & new format groups */
    for (latest_format = false; latest_format <= true; latest_format++) {
        hid_t current_fapl_id = H5I_INVALID_HID;

        /* Set the fapl for different file formats */
        if (latest_format) {
            puts("\nTesting with the latest file format:");
            current_fapl_id = fapl_id_new;
        }
        else {
            puts("Testing with the default file format:");
            current_fapl_id = fapl_id_old;
        }

        /* Create the common file used by some of the tests */
        if ((fid = H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, current_fapl_id)) < 0)
            FAIL_STACK_ERROR;

        /* Create a group that will be used in the file set read test */
        if ((gid = H5Gcreate2(fid, "emit-diagnostics", H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0)
            FAIL_STACK_ERROR;
        if (H5Gclose(gid) < 0)
            FAIL_STACK_ERROR;

        /* These tests use a common file */
        nerrors += test_non_extendible(fid);
        nerrors += test_too_small(fid);
        nerrors += test_large_enough_current_eventual(fid);
        nerrors += test_large_enough_current_not_eventual(fid);
        nerrors += test_unlimited(fid);
        nerrors += test_multiple_files(fid);

        /* These tests use no file */
        nerrors += test_add_to_unlimited();
        nerrors += test_overflow();

        /* These file set tests use the VFD-aware fapl */
        nerrors += test_read_file_set(current_fapl_id);
        nerrors += test_write_file_set(current_fapl_id);
        nerrors += test_path_absolute(current_fapl_id);
        nerrors += test_path_relative(current_fapl_id);
        nerrors += test_path_relative_cwd(current_fapl_id);

        /* Verify symbol table messages are cached */
        nerrors += (h5_verify_cached_stabs(EXT_FNAME, current_fapl_id) < 0 ? 1 : 0);

        /* Close the common file */
        if (H5Fclose(fid) < 0)
            FAIL_STACK_ERROR;

    } /* end for old and new format */

    if (nerrors > 0)
        goto error;

    /* Close the new ff fapl. h5_cleanup will take care of the old ff fapl */
    if (H5Pclose(fapl_id_new) < 0)
        FAIL_STACK_ERROR;

    puts("All external storage tests passed.");

    /* Clean up files used by file set tests */
    if (h5_cleanup(EXT_FNAME, fapl_id_old)) {
        HDremove("extern_1r.raw");
        HDremove("extern_2r.raw");
        HDremove("extern_3r.raw");
        HDremove("extern_4r.raw");

        HDremove("extern_1w.raw");
        HDremove("extern_2w.raw");
        HDremove("extern_3w.raw");
        HDremove("extern_4w.raw");

        HDrmdir("extern_dir");
    }

    return EXIT_SUCCESS;

error:
    H5E_BEGIN_TRY
    {
        H5Fclose(fid);
        H5Pclose(fapl_id_old);
        H5Pclose(fapl_id_new);
        H5Gclose(gid);
    }
    H5E_END_TRY
    nerrors = MAX(1, nerrors);
    printf("%d TEST%s FAILED.\n", nerrors, 1 == nerrors ? "" : "s");
    return EXIT_FAILURE;
} /* end main() */