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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/****************/
/* Module Setup */
/****************/

#include "H5Dmodule.h" /* This source code file is part of the H5D module */

/***********/
/* Headers */
/***********/
#include "H5private.h"   /* Generic Functions                        */
#include "H5Dpkg.h"      /* Datasets                                 */
#include "H5Eprivate.h"  /* Error handling                           */
#include "H5HLprivate.h" /* Local heaps                              */

/****************/
/* Local Macros */
/****************/

/******************/
/* Local Typedefs */
/******************/

/********************/
/* Local Prototypes */
/********************/

/*********************/
/* Package Variables */
/*********************/

/* Format version bounds for layout */
const unsigned H5O_layout_ver_bounds[] = {
    H5O_LAYOUT_VERSION_1,                      /* H5F_LIBVER_EARLIEST */
    H5O_LAYOUT_VERSION_3, /* H5F_LIBVER_V18 */ /* H5O_LAYOUT_VERSION_DEFAULT */
    H5O_LAYOUT_VERSION_4,                      /* H5F_LIBVER_V110 */
    H5O_LAYOUT_VERSION_4,                      /* H5F_LIBVER_V112 */
    H5O_LAYOUT_VERSION_LATEST                  /* H5F_LIBVER_LATEST */
};

/*****************************/
/* Library Private Variables */
/*****************************/

/*******************/
/* Local Variables */
/*******************/

/*-------------------------------------------------------------------------
 * Function:    H5D__layout_set_io_ops
 *
 * Purpose:     Set the I/O operation function pointers for a dataset,
 *              according to the dataset's layout
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Quincey Koziol
 *              Thursday, March 20, 2008
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__layout_set_io_ops(const H5D_t *dataset)
{
    herr_t ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE

    /* check args */
    HDassert(dataset);

    /* Set the I/O functions for each layout type */
    switch (dataset->shared->layout.type) {
        case H5D_CONTIGUOUS:
            if (dataset->shared->dcpl_cache.efl.nused > 0)
                dataset->shared->layout.ops = H5D_LOPS_EFL;
            else
                dataset->shared->layout.ops = H5D_LOPS_CONTIG;
            break;

        case H5D_CHUNKED:
            dataset->shared->layout.ops = H5D_LOPS_CHUNK;

            /* Set the chunk operations */
            switch (dataset->shared->layout.u.chunk.idx_type) {
                case H5D_CHUNK_IDX_BTREE:
                    dataset->shared->layout.storage.u.chunk.ops = H5D_COPS_BTREE;
                    break;

                case H5D_CHUNK_IDX_NONE:
                    dataset->shared->layout.storage.u.chunk.ops = H5D_COPS_NONE;
                    break;

                case H5D_CHUNK_IDX_SINGLE:
                    dataset->shared->layout.storage.u.chunk.ops = H5D_COPS_SINGLE;
                    break;

                case H5D_CHUNK_IDX_FARRAY:
                    dataset->shared->layout.storage.u.chunk.ops = H5D_COPS_FARRAY;
                    break;

                case H5D_CHUNK_IDX_EARRAY:
                    dataset->shared->layout.storage.u.chunk.ops = H5D_COPS_EARRAY;
                    break;

                case H5D_CHUNK_IDX_BT2:
                    dataset->shared->layout.storage.u.chunk.ops = H5D_COPS_BT2;
                    break;

                case H5D_CHUNK_IDX_NTYPES:
                default:
                    HDassert(0 && "Unknown chunk index method!");
                    HGOTO_ERROR(H5E_DATASET, H5E_UNSUPPORTED, FAIL, "unknown chunk index method")
            } /* end switch */
            break;

        case H5D_COMPACT:
            dataset->shared->layout.ops = H5D_LOPS_COMPACT;
            break;

        case H5D_VIRTUAL:
            dataset->shared->layout.ops = H5D_LOPS_VIRTUAL;
            break;

        case H5D_LAYOUT_ERROR:
        case H5D_NLAYOUTS:
        default:
            HGOTO_ERROR(H5E_DATASET, H5E_UNSUPPORTED, FAIL, "unknown storage method")
    } /* end switch */ /*lint !e788 All appropriate cases are covered */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__layout_set_io_ops() */

/*-------------------------------------------------------------------------
 * Function:    H5D__layout_meta_size
 *
 * Purpose:     Returns the size of the raw message in bytes except raw data
 *              part for compact dataset.  This function doesn't take into
 *              account message alignment.
 *
 * Return:      Success:        Message data size in bytes
 *              Failure:        0
 *
 * Programmer:  Raymond Lu
 *              August 14, 2002
 *
 *-------------------------------------------------------------------------
 */
size_t
H5D__layout_meta_size(const H5F_t *f, const H5O_layout_t *layout, hbool_t include_compact_data)
{
    size_t ret_value = 0; /* Return value */

    FUNC_ENTER_PACKAGE

    /* check args */
    HDassert(f);
    HDassert(layout);

    ret_value = 1 + /* Version number                       */
                1;  /* layout class type                    */

    switch (layout->type) {
        case H5D_COMPACT:
            /* This information only present in older versions of message */
            /* Size of raw data */
            ret_value += 2;
            if (include_compact_data)
                ret_value += layout->storage.u.compact.size; /* data for compact dataset             */
            break;

        case H5D_CONTIGUOUS:
            /* This information only present in older versions of message */
            ret_value += H5F_SIZEOF_ADDR(f); /* Address of data */
            ret_value += H5F_SIZEOF_SIZE(f); /* Length of data */
            break;

        case H5D_CHUNKED:
            if (layout->version < H5O_LAYOUT_VERSION_4) {
                /* Number of dimensions (1 byte) */
                HDassert(layout->u.chunk.ndims > 0 && layout->u.chunk.ndims <= H5O_LAYOUT_NDIMS);
                ret_value++;

                /* B-tree address */
                ret_value += H5F_SIZEOF_ADDR(f); /* Address of data */

                /* Dimension sizes */
                ret_value += layout->u.chunk.ndims * 4;
            } /* end if */
            else {
                /* Chunked layout feature flags */
                ret_value++;

                /* Number of dimensions (1 byte) */
                HDassert(layout->u.chunk.ndims > 0 && layout->u.chunk.ndims <= H5O_LAYOUT_NDIMS);
                ret_value++;

                /* Encoded # of bytes for each chunk dimension */
                HDassert(layout->u.chunk.enc_bytes_per_dim > 0 && layout->u.chunk.enc_bytes_per_dim <= 8);
                ret_value++;

                /* Dimension sizes */
                ret_value += layout->u.chunk.ndims * (size_t)layout->u.chunk.enc_bytes_per_dim;

                /* Type of chunk index */
                ret_value++;

                switch (layout->u.chunk.idx_type) {
                    case H5D_CHUNK_IDX_BTREE:
                        HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, 0,
                                    "v1 B-tree index type found for layout message >v3")

                    case H5D_CHUNK_IDX_NONE:
                        /* nothing */
                        break;

                    case H5D_CHUNK_IDX_SINGLE:
                        /* Possible filter information */
                        if (layout->u.chunk.flags & H5O_LAYOUT_CHUNK_SINGLE_INDEX_WITH_FILTER) {
                            ret_value += H5F_SIZEOF_SIZE(f); /* Size of chunk (in file) */
                            ret_value += 4;                  /* Filter mask for chunk */
                        }                                    /* end if */
                        break;

                    case H5D_CHUNK_IDX_FARRAY:
                        /* Fixed array creation parameters */
                        ret_value += H5D_FARRAY_CREATE_PARAM_SIZE;
                        break;

                    case H5D_CHUNK_IDX_EARRAY:
                        /* Extensible array creation parameters */
                        ret_value += H5D_EARRAY_CREATE_PARAM_SIZE;
                        break;

                    case H5D_CHUNK_IDX_BT2:
                        /* v2 B-tree creation parameters */
                        ret_value += H5D_BT2_CREATE_PARAM_SIZE;
                        break;

                    case H5D_CHUNK_IDX_NTYPES:
                    default:
                        HGOTO_ERROR(H5E_OHDR, H5E_CANTENCODE, 0, "Invalid chunk index type")
                } /* end switch */

                /* Chunk index address */
                ret_value += H5F_SIZEOF_ADDR(f);
            } /* end else */
            break;

        case H5D_VIRTUAL:
            ret_value += H5F_SIZEOF_ADDR(f); /* Address of global heap */
            ret_value += 4;                  /* Global heap index */
            break;

        case H5D_LAYOUT_ERROR:
        case H5D_NLAYOUTS:
        default:
            HGOTO_ERROR(H5E_OHDR, H5E_CANTENCODE, 0, "Invalid layout class")
    } /* end switch */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__layout_meta_size() */

/*-------------------------------------------------------------------------
 * Function:    H5D__layout_set_version
 *
 * Purpose:     Set the version to encode a layout with.
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Vailin Choi; December 2017
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__layout_set_version(H5F_t *f, H5O_layout_t *layout)
{
    unsigned version;             /* Message version */
    herr_t   ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_NOAPI(FAIL)

    /* Sanity check */
    HDassert(layout);
    HDassert(f);

    /* Upgrade to the version indicated by the file's low bound if higher */
    version = MAX(layout->version, H5O_layout_ver_bounds[H5F_LOW_BOUND(f)]);

    /* Version bounds check */
    if (version > H5O_layout_ver_bounds[H5F_HIGH_BOUND(f)])
        HGOTO_ERROR(H5E_DATASET, H5E_BADRANGE, FAIL, "layout version out of bounds")

    /* Set the message version */
    layout->version = version;

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__layout_set_version() */

/*-------------------------------------------------------------------------
 * Function:    H5D__layout_set_latest_indexing
 *
 * Purpose:     Set the latest indexing type for a layout message
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Quincey Koziol
 *              Thursday, January 15, 2009
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__layout_set_latest_indexing(H5O_layout_t *layout, const H5S_t *space, const H5D_dcpl_cache_t *dcpl_cache)
{
    herr_t ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity check */
    HDassert(layout);
    HDassert(space);
    HDassert(dcpl_cache);

    /* The indexing methods only apply to chunked datasets (currently) */
    if (layout->type == H5D_CHUNKED) {
        int      sndims; /* Rank of dataspace */
        unsigned ndims;  /* Rank of dataspace */

        /* Query the dimensionality of the dataspace */
        if ((sndims = H5S_GET_EXTENT_NDIMS(space)) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "invalid dataspace rank")
        ndims = (unsigned)sndims;

        /* Avoid scalar/null dataspace */
        if (ndims > 0) {
            hsize_t  max_dims[H5O_LAYOUT_NDIMS]; /* Maximum dimension sizes */
            hsize_t  cur_dims[H5O_LAYOUT_NDIMS]; /* Current dimension sizes */
            unsigned unlim_count = 0;            /* Count of unlimited max. dimensions */
            hbool_t  single      = TRUE;         /* Fulfill single chunk indexing */
            unsigned u;                          /* Local index variable */

            /* Query the dataspace's dimensions */
            if (H5S_get_simple_extent_dims(space, cur_dims, max_dims) < 0)
                HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get dataspace max. dimensions")

            /* Spin through the max. dimensions, looking for unlimited dimensions */
            for (u = 0; u < ndims; u++) {
                if (max_dims[u] == H5S_UNLIMITED)
                    unlim_count++;
                if (cur_dims[u] != max_dims[u] || cur_dims[u] != layout->u.chunk.dim[u])
                    single = FALSE;
            } /* end for */

            /* Chunked datasets with unlimited dimension(s) */
            if (unlim_count) {          /* dataset with unlimited dimension(s) must be chunked */
                if (1 == unlim_count) { /* Chunked dataset with only 1 unlimited dimension */
                    /* Set the chunk index type to an extensible array */
                    layout->u.chunk.idx_type         = H5D_CHUNK_IDX_EARRAY;
                    layout->storage.u.chunk.idx_type = H5D_CHUNK_IDX_EARRAY;
                    layout->storage.u.chunk.ops      = H5D_COPS_EARRAY;

                    /* Set the extensible array creation parameters */
                    /* (use hard-coded defaults for now, until we give applications
                     *          control over this with a property list - QAK)
                     */
                    layout->u.chunk.u.earray.cparam.max_nelmts_bits       = H5D_EARRAY_MAX_NELMTS_BITS;
                    layout->u.chunk.u.earray.cparam.idx_blk_elmts         = H5D_EARRAY_IDX_BLK_ELMTS;
                    layout->u.chunk.u.earray.cparam.sup_blk_min_data_ptrs = H5D_EARRAY_SUP_BLK_MIN_DATA_PTRS;
                    layout->u.chunk.u.earray.cparam.data_blk_min_elmts    = H5D_EARRAY_DATA_BLK_MIN_ELMTS;
                    layout->u.chunk.u.earray.cparam.max_dblk_page_nelmts_bits =
                        H5D_EARRAY_MAX_DBLOCK_PAGE_NELMTS_BITS;
                }      /* end if */
                else { /* Chunked dataset with > 1 unlimited dimensions */
                    /* Set the chunk index type to v2 B-tree */
                    layout->u.chunk.idx_type         = H5D_CHUNK_IDX_BT2;
                    layout->storage.u.chunk.idx_type = H5D_CHUNK_IDX_BT2;
                    layout->storage.u.chunk.ops      = H5D_COPS_BT2;

                    /* Set the v2 B-tree creation parameters */
                    /* (use hard-coded defaults for now, until we give applications
                     *          control over this with a property list - QAK)
                     */
                    layout->u.chunk.u.btree2.cparam.node_size     = H5D_BT2_NODE_SIZE;
                    layout->u.chunk.u.btree2.cparam.split_percent = H5D_BT2_SPLIT_PERC;
                    layout->u.chunk.u.btree2.cparam.merge_percent = H5D_BT2_MERGE_PERC;
                }  /* end else */
            }      /* end if */
            else { /* Chunked dataset with fixed dimensions */
                /* Check for correct condition for using "single chunk" chunk index */
                if (single) {
                    layout->u.chunk.idx_type         = H5D_CHUNK_IDX_SINGLE;
                    layout->storage.u.chunk.idx_type = H5D_CHUNK_IDX_SINGLE;
                    layout->storage.u.chunk.ops      = H5D_COPS_SINGLE;
                } /* end if */
                else if (!dcpl_cache->pline.nused && dcpl_cache->fill.alloc_time == H5D_ALLOC_TIME_EARLY) {

                    /* Set the chunk index type to "none" Index */
                    layout->u.chunk.idx_type         = H5D_CHUNK_IDX_NONE;
                    layout->storage.u.chunk.idx_type = H5D_CHUNK_IDX_NONE;
                    layout->storage.u.chunk.ops      = H5D_COPS_NONE;
                } /* end else-if */
                else {
                    /* Set the chunk index type to Fixed Array */
                    layout->u.chunk.idx_type         = H5D_CHUNK_IDX_FARRAY;
                    layout->storage.u.chunk.idx_type = H5D_CHUNK_IDX_FARRAY;
                    layout->storage.u.chunk.ops      = H5D_COPS_FARRAY;

                    /* Set the fixed array creation parameters */
                    /* (use hard-coded defaults for now, until we give applications
                     *          control over this with a property list - QAK)
                     */
                    layout->u.chunk.u.farray.cparam.max_dblk_page_nelmts_bits =
                        H5D_FARRAY_MAX_DBLK_PAGE_NELMTS_BITS;
                } /* end else */
            }     /* end else */
        }         /* end if */
    }             /* end if */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__layout_set_latest_indexing() */

/*-------------------------------------------------------------------------
 * Function:    H5D__layout_oh_create
 *
 * Purpose:     Create layout/pline/efl information for dataset
 *
 * Return:      Success:    SUCCEED
 *              Failure:    FAIL
 *
 * Programmer:  Quincey Koziol
 *              Monday, July 27, 2009
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__layout_oh_create(H5F_t *file, H5O_t *oh, H5D_t *dset, hid_t dapl_id)
{
    H5O_layout_t     *layout;                /* Dataset's layout information */
    const H5O_fill_t *fill_prop;             /* Pointer to dataset's fill value information */
    unsigned          layout_mesg_flags;     /* Flags for inserting layout message */
    hbool_t           layout_init = FALSE;   /* Flag to indicate that chunk information was initialized */
    herr_t            ret_value   = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE_TAG(dset->oloc.addr)

    /* Sanity checking */
    HDassert(file);
    HDassert(oh);
    HDassert(dset);

    /* Set some local variables, for convenience */
    layout    = &dset->shared->layout;
    fill_prop = &dset->shared->dcpl_cache.fill;

    /* Update the filters message, if this is a chunked dataset */
    if (layout->type == H5D_CHUNKED) {
        H5O_pline_t *pline; /* Dataset's I/O pipeline information */

        pline = &dset->shared->dcpl_cache.pline;
        if (pline->nused > 0 &&
            H5O_msg_append_oh(file, oh, H5O_PLINE_ID, H5O_MSG_FLAG_CONSTANT, 0, pline) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to update filter header message")
    } /* end if */

    /* Initialize the layout information for the new dataset */
    if (dset->shared->layout.ops->init && (dset->shared->layout.ops->init)(file, dset, dapl_id) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize layout information")

    /* Indicate that the layout information was initialized */
    layout_init = TRUE;

    /*
     * Allocate storage if space allocate time is early; otherwise delay
     * allocation until later.
     */
    if (fill_prop->alloc_time == H5D_ALLOC_TIME_EARLY)
        if (H5D__alloc_storage(dset, H5D_ALLOC_CREATE, FALSE, NULL) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize storage")

    /* Update external storage message, if it's used */
    if (dset->shared->dcpl_cache.efl.nused > 0) {
        H5O_efl_t *efl = &dset->shared->dcpl_cache.efl; /* Dataset's external file list */
        H5HL_t    *heap;                                /* Pointer to local heap for EFL file names */
        size_t     heap_size = H5HL_ALIGN(1);
        size_t     u;
        size_t     name_offset;

        /* Determine size of heap needed to stored the file names */
        for (u = 0; u < efl->nused; ++u)
            heap_size += H5HL_ALIGN(HDstrlen(efl->slot[u].name) + 1);

        /* Create the heap for the EFL file names */
        if (H5HL_create(file, heap_size, &efl->heap_addr /*out*/) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to create EFL file name heap")

        /* Pin the heap down in memory */
        if (NULL == (heap = H5HL_protect(file, efl->heap_addr, H5AC__NO_FLAGS_SET)))
            HGOTO_ERROR(H5E_DATASET, H5E_CANTPROTECT, FAIL, "unable to protect EFL file name heap")

        /* Insert "empty" name first */
        if (H5HL_insert(file, heap, (size_t)1, "", &name_offset) < 0) {
            H5HL_unprotect(heap);
            HGOTO_ERROR(H5E_DATASET, H5E_CANTINSERT, FAIL, "unable to insert file name into heap")
        }

        for (u = 0; u < efl->nused; ++u) {
            /* Insert file name into heap */
            if (H5HL_insert(file, heap, HDstrlen(efl->slot[u].name) + 1, efl->slot[u].name, &name_offset) <
                0) {
                H5HL_unprotect(heap);
                HGOTO_ERROR(H5E_DATASET, H5E_CANTINSERT, FAIL, "unable to insert file name into heap")
            }

            /* Store EFL file name offset */
            efl->slot[u].name_offset = name_offset;
        }

        /* Release the heap */
        if (H5HL_unprotect(heap) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTUNPROTECT, FAIL, "unable to unprotect EFL file name heap")
        heap = NULL;

        /* Insert EFL message into dataset object header */
        if (H5O_msg_append_oh(file, oh, H5O_EFL_ID, H5O_MSG_FLAG_CONSTANT, 0, efl) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to update external file list message")
    } /* end if */

    /* Create layout message */
    /* (Don't make layout message constant unless allocation time is early and
     *  non-filtered and has >0 elements, since space may not be allocated -QAK) */
    /* (Note: this is relying on H5D__alloc_storage not calling H5O_msg_write during dataset creation) */
    if (fill_prop->alloc_time == H5D_ALLOC_TIME_EARLY && H5D_COMPACT != layout->type &&
        !dset->shared->dcpl_cache.pline.nused && (0 != H5S_GET_EXTENT_NPOINTS(dset->shared->space)))
        layout_mesg_flags = H5O_MSG_FLAG_CONSTANT;
    else
        layout_mesg_flags = 0;

    /* Store VDS info in global heap */
    if (H5D_VIRTUAL == layout->type)
        if (H5D__virtual_store_layout(file, layout) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTSET, FAIL, "unable to store VDS info")

    /* Create layout message */
    if (H5O_msg_append_oh(file, oh, H5O_LAYOUT_ID, layout_mesg_flags, 0, layout) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to update layout")

done:
    /* Error cleanup */
    if (ret_value < 0)
        if (layout_init)
            /* Destroy any cached layout information for the dataset */
            if (dset->shared->layout.ops->dest && (dset->shared->layout.ops->dest)(dset) < 0)
                HDONE_ERROR(H5E_DATASET, H5E_CANTRELEASE, FAIL, "unable to destroy layout info")

    FUNC_LEAVE_NOAPI_TAG(ret_value)
} /* end H5D__layout_oh_create() */

/*-------------------------------------------------------------------------
 * Function:    H5D__layout_oh_read
 *
 * Purpose:     Read layout/pline/efl information for dataset
 *
 * Return:      Success:    SUCCEED
 *              Failure:    FAIL
 *
 * Programmer:  Quincey Koziol
 *              Monday, July 27, 2009
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__layout_oh_read(H5D_t *dataset, hid_t dapl_id, H5P_genplist_t *plist)
{
    htri_t  msg_exists;              /* Whether a particular type of message exists */
    hbool_t layout_copied = FALSE;   /* Flag to indicate that layout message was copied */
    herr_t  ret_value     = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checking */
    HDassert(dataset);
    HDassert(plist);

    /* Get the optional filters message */
    if ((msg_exists = H5O_msg_exists(&(dataset->oloc), H5O_PLINE_ID)) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't check if message exists")
    if (msg_exists) {
        /* Retrieve the I/O pipeline message */
        if (NULL == H5O_msg_read(&(dataset->oloc), H5O_PLINE_ID, &dataset->shared->dcpl_cache.pline))
            HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't retrieve message")

        /* Set the I/O pipeline info in the property list */
        if (H5P_set(plist, H5O_CRT_PIPELINE_NAME, &dataset->shared->dcpl_cache.pline) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTSET, FAIL, "can't set pipeline")
    } /* end if */

    /*
     * Get the raw data layout info.  It's actually stored in two locations:
     * the storage message of the dataset (dataset->storage) and certain
     * values are copied to the dataset create plist so the user can query
     * them.
     */
    if (NULL == H5O_msg_read(&(dataset->oloc), H5O_LAYOUT_ID, &(dataset->shared->layout)))
        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to read data layout message")
    layout_copied = TRUE;

    /* Check for external file list message (which might not exist) */
    if ((msg_exists = H5O_msg_exists(&(dataset->oloc), H5O_EFL_ID)) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't check if message exists")
    if (msg_exists) {
        /* Retrieve the EFL  message */
        if (NULL == H5O_msg_read(&(dataset->oloc), H5O_EFL_ID, &dataset->shared->dcpl_cache.efl))
            HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't retrieve message")

        /* Set the EFL info in the property list */
        if (H5P_set(plist, H5D_CRT_EXT_FILE_LIST_NAME, &dataset->shared->dcpl_cache.efl) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_CANTSET, FAIL, "can't set external file list")

        /* Set the dataset's I/O operations */
        dataset->shared->layout.ops = H5D_LOPS_EFL;
    } /* end if */

    /* Sanity check that the layout operations are set up */
    HDassert(dataset->shared->layout.ops);

    /* Initialize the layout information for the dataset */
    if (dataset->shared->layout.ops->init &&
        (dataset->shared->layout.ops->init)(dataset->oloc.file, dataset, dapl_id) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize layout information")

    /* Adjust chunk dimensions to omit datatype size (in last dimension) for creation property */
    if (H5D_CHUNKED == dataset->shared->layout.type)
        dataset->shared->layout.u.chunk.ndims--;

    /* Copy layout to the DCPL */
    if (H5P_set(plist, H5D_CRT_LAYOUT_NAME, &dataset->shared->layout) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTSET, FAIL, "can't set layout")

    /* Set chunk sizes */
    if (H5D_CHUNKED == dataset->shared->layout.type)
        if (H5D__chunk_set_sizes(dataset) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_BADVALUE, FAIL, "unable to set chunk sizes")

done:
    if (ret_value < 0 && layout_copied)
        if (H5O_msg_reset(H5O_LAYOUT_ID, &dataset->shared->layout) < 0)
            HDONE_ERROR(H5E_DATASET, H5E_CANTRESET, FAIL, "unable to reset layout info")

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__layout_oh_read() */

/*-------------------------------------------------------------------------
 * Function:    H5D__layout_oh_write
 *
 * Purpose:     Write layout information for dataset
 *
 * Return:      Success:    SUCCEED
 *              Failure:    FAIL
 *
 * Programmer:  Quincey Koziol
 *              Monday, July 27, 2009
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5D__layout_oh_write(const H5D_t *dataset, H5O_t *oh, unsigned update_flags)
{
    htri_t msg_exists;          /* Whether the layout message exists */
    herr_t ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_PACKAGE

    /* Sanity checking */
    HDassert(dataset);
    HDassert(oh);

    /* Check if the layout message has been added to the dataset's header */
    if ((msg_exists = H5O_msg_exists_oh(oh, H5O_LAYOUT_ID)) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "unable to check if layout message exists")
    if (msg_exists) {
        /* Write the layout message to the dataset's header */
        if (H5O_msg_write_oh(dataset->oloc.file, oh, H5O_LAYOUT_ID, 0, update_flags,
                             &dataset->shared->layout) < 0)
            HGOTO_ERROR(H5E_DATASET, H5E_WRITEERROR, FAIL, "unable to update layout message")
    } /* end if */

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5D__layout_oh_write() */