path: root/hl/src/H5PT.c

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * Copyright by The HDF Group.                                               *
 * Copyright by the Board of Trustees of the University of Illinois.         *
 * 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://support.hdfgroup.org/ftp/HDF5/releases.  *
 * If you do not have access to either file, you may request a copy from     *
 * help@hdfgroup.org.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

#include "H5PTprivate.h"
#include "H5TBprivate.h"

/*  Packet Table private data */

typedef struct {
    hid_t   dset_id;       /* The ID of the dataset containing this table */
    hid_t   type_id;       /* The ID of the packet table's native datatype */
    hsize_t current_index; /* The index of the packet that get_next_packet will read next */
    hsize_t size;          /* The number of packets currently contained in this table */
} htbl_t;

static hsize_t    H5PT_ptable_count   = 0;
static H5I_type_t H5PT_ptable_id_type = H5I_UNINIT;

#define H5PT_HASH_TABLE_SIZE 64

/* Packet Table private functions */
static herr_t H5PT_free_id(void *id);
static herr_t H5PT_close(htbl_t *table);
static herr_t H5PT_create_index(htbl_t *table_id);
static herr_t H5PT_set_index(htbl_t *table_id, hsize_t pt_index);
static herr_t H5PT_get_index(htbl_t *table_id, hsize_t *pt_index);

/*-------------------------------------------------------------------------
 *
 * Create/Open/Close functions
 *
 *-------------------------------------------------------------------------
 */

/*-------------------------------------------------------------------------
 * Function: H5PTcreate
 *
 * Purpose: Creates a dataset containing a table and returns the Identifier
 *          of the table. (Copied mostly from H5PTcreate_fl)
 *
 * Return: Success: table ID, Failure: FAIL
 *
 * Programmer: Nat Furrer (Author of H5PTcreate_fl)
 *             James Laird (Author of H5PTcreate_fl)
 *
 * Date: March 12, 2004
 *
 * Comments: This function does not handle fill data
 *           currently.  Fill data is not necessary because the
 *           table is initially of size 0.
 *
 * Modifications:
 *	Mar 1, 2016
 *		This function is added to replace H5PTcreate_fl and it differs
 *		from H5PTcreate_fl only because its last argument is plist_id
 *		instead of compression; this is to allow flexible compression.
 *		-BMR
 *
 *-------------------------------------------------------------------------
 */
hid_t
H5PTcreate(hid_t loc_id, const char *dset_name, hid_t dtype_id, hsize_t chunk_size, hid_t plist_id)
{
    htbl_t *table        = NULL;
    hid_t   dset_id      = H5I_INVALID_HID;
    hid_t   space_id     = H5I_INVALID_HID;
    hid_t   plistcopy_id = H5I_INVALID_HID;
    hsize_t dims[1];
    hsize_t dims_chunk[1];
    hsize_t maxdims[1];
    hid_t   ret_value = H5I_INVALID_HID;

    /* check the arguments */
    if (dset_name == NULL) {
        goto error;
    }

    /* Register the packet table ID type if this is the first table created */
    if (H5PT_ptable_id_type < 0)
        if ((H5PT_ptable_id_type =
                 H5Iregister_type((size_t)H5PT_HASH_TABLE_SIZE, 0, (H5I_free_t)H5PT_free_id)) < 0)
            goto error;

    /* Get memory for the table identifier */
    table = (htbl_t *)HDmalloc(sizeof(htbl_t));
    if (table == NULL) {
        goto error;
    }
    table->dset_id = H5I_INVALID_HID;
    table->type_id = H5I_INVALID_HID;

    /* Create a simple data space with unlimited size */
    dims[0]       = 0;
    dims_chunk[0] = chunk_size;
    maxdims[0]    = H5S_UNLIMITED;
    if ((space_id = H5Screate_simple(1, dims, maxdims)) < 0)
        goto error;

    /* Modify dataset creation properties to enable chunking  */
    if (plist_id == H5P_DEFAULT) {
        plistcopy_id = H5Pcreate(H5P_DATASET_CREATE);
    }
    else {
        plistcopy_id = H5Pcopy(plist_id);
    }
    if (chunk_size > 0) {
        if (H5Pset_chunk(plistcopy_id, 1, dims_chunk) < 0)
            goto error;
    }

    /* Create the dataset. */
    if ((dset_id =
             H5Dcreate2(loc_id, dset_name, dtype_id, space_id, H5P_DEFAULT, plistcopy_id, H5P_DEFAULT)) < 0)
        goto error;

    /* Create the table identifier */
    table->dset_id = dset_id;

    /* Terminate access to the data space. */
    if (H5Sclose(space_id) < 0)
        goto error;

    /* End access to the property list */
    if (H5Pclose(plistcopy_id) < 0)
        goto error;

    /* Make a copy of caller's datatype and save it in the table structure.
       It will be closed when the table is closed */
    if ((table->type_id = H5Tcopy(dtype_id)) < 0)
        goto error;

    H5PT_create_index(table);
    table->size = 0;

    /* Get an ID for this table */
    ret_value = H5Iregister(H5PT_ptable_id_type, table);
    if (ret_value != H5I_INVALID_HID)
        H5PT_ptable_count++;
    else
        H5PT_close(table);

    return ret_value;

error:
    if (space_id != H5I_INVALID_HID)
        H5Sclose(space_id);
    if (plistcopy_id != H5I_INVALID_HID)
        H5Pclose(plistcopy_id);
    if (dset_id != H5I_INVALID_HID)
        H5Dclose(dset_id);
    if (table) {
        if (table->type_id != H5I_INVALID_HID)
            H5Tclose(table->type_id);
        HDfree(table);
    }

    return ret_value;
} /* H5PTcreate */

/*-------------------------------------------------------------------------
 * Function: H5PTcreate_fl
 *
 * Purpose: Creates a dataset containing a table and returns the Identifier
 *          of the table.
 *
 * Return: Success: table ID, Failure: Negative
 *
 * Programmer: Nat Furrer
 *             James Laird
 *
 * Date: March 12, 2004
 *
 * Comments: This function does not handle fill data
 *           currently.  Fill data is not necessary because the
 *           table is initially of size 0.
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */

hid_t
H5PTcreate_fl(hid_t loc_id, const char *dset_name, hid_t dtype_id, hsize_t chunk_size, int compression)
{
    htbl_t *table    = NULL;
    hid_t   dset_id  = H5I_INVALID_HID;
    hid_t   space_id = H5I_INVALID_HID;
    hid_t   plist_id = H5I_INVALID_HID;
    hsize_t dims[1];
    hsize_t dims_chunk[1];
    hsize_t maxdims[1];
    hid_t   ret_value = H5I_INVALID_HID;

    /* check the arguments */
    if (dset_name == NULL) {
        goto error;
    }

    /* Register the packet table ID type if this is the first table created */
    if (H5PT_ptable_id_type < 0)
        if ((H5PT_ptable_id_type =
                 H5Iregister_type((size_t)H5PT_HASH_TABLE_SIZE, 0, (H5I_free_t)H5PT_free_id)) < 0)
            goto error;

    /* Get memory for the table identifier */
    table = (htbl_t *)HDmalloc(sizeof(htbl_t));
    if (table == NULL) {
        goto error;
    }
    table->dset_id = H5I_INVALID_HID;
    table->type_id = H5I_INVALID_HID;

    /* Create a simple data space with unlimited size */
    dims[0]       = 0;
    dims_chunk[0] = chunk_size;
    maxdims[0]    = H5S_UNLIMITED;
    if ((space_id = H5Screate_simple(1, dims, maxdims)) < 0)
        goto error;

    /* Modify dataset creation properties to enable chunking  */
    plist_id = H5Pcreate(H5P_DATASET_CREATE);
    if (H5Pset_chunk(plist_id, 1, dims_chunk) < 0)
        goto error;
    if (compression >= 0 && compression <= 9)
        if (H5Pset_deflate(plist_id, (unsigned)compression) < 0)
            goto error;

    /* Create the dataset. */
    if ((dset_id = H5Dcreate2(loc_id, dset_name, dtype_id, space_id, H5P_DEFAULT, plist_id, H5P_DEFAULT)) < 0)
        goto error;

    /* Create the table identifier */
    table->dset_id = dset_id;

    /* Terminate access to the data space. */
    if (H5Sclose(space_id) < 0)
        goto error;

    /* End access to the property list */
    if (H5Pclose(plist_id) < 0)
        goto error;

    /* Make a copy of caller's datatype and save it in the table structure.
       It will be closed when the table is closed */
    if ((table->type_id = H5Tcopy(dtype_id)) < 0)
        goto error;

    H5PT_create_index(table);
    table->size = 0;

    /* Get an ID for this table */
    ret_value = H5Iregister(H5PT_ptable_id_type, table);
    if (ret_value != H5I_INVALID_HID)
        H5PT_ptable_count++;
    else
        H5PT_close(table);

    return ret_value;

error:
    if (space_id != H5I_INVALID_HID)
        H5Sclose(space_id);
    if (plist_id != H5I_INVALID_HID)
        H5Pclose(plist_id);
    if (dset_id != H5I_INVALID_HID)
        H5Dclose(dset_id);
    if (table) {
        if (table->type_id != H5I_INVALID_HID)
            H5Tclose(table->type_id);
        HDfree(table);
    }

    return ret_value;
} /* H5PTcreate_fl */

/*-------------------------------------------------------------------------
 * Function: H5PTopen
 *
 * Purpose: Opens a dataset containing a table and returns the Identifier
 *          of the table.
 *
 * Return: Success: table ID, Failure: Negative
 *
 * Programmer: Nat Furrer
 *             James Laird
 *
 * Date: March 10, 2004
 *
 * Comments:
 *
 * Modifications:
 *
 * 		John Mainzer -- 4/23/08
 * 		Added error check on malloc of table, initialized fields
 * 		in table to keep lower level code from choking on bogus
 * 		data in error cases.
 *
 *-------------------------------------------------------------------------
 */
hid_t
H5PTopen(hid_t loc_id, const char *dset_name)
{
    hid_t   type_id  = H5I_INVALID_HID;
    hid_t   space_id = H5I_INVALID_HID;
    htbl_t *table    = NULL;
    hsize_t dims[1];
    hid_t   ret_value = H5I_INVALID_HID;

    /* check the arguments */
    if (dset_name == NULL) {
        goto error;
    }

    /* Register the packet table ID type if this is the first table created */
    if (H5PT_ptable_id_type < 0)
        if ((H5PT_ptable_id_type =
                 H5Iregister_type((size_t)H5PT_HASH_TABLE_SIZE, 0, (H5I_free_t)H5PT_free_id)) < 0)
            goto error;

    table = (htbl_t *)HDmalloc(sizeof(htbl_t));
    if (table == NULL) {
        goto error;
    }
    table->dset_id = H5I_INVALID_HID;
    table->type_id = H5I_INVALID_HID;

    /* Open the dataset */
    if ((table->dset_id = H5Dopen2(loc_id, dset_name, H5P_DEFAULT)) < 0)
        goto error;

    /* Get the dataset's disk datatype */
    if ((type_id = H5Dget_type(table->dset_id)) < 0)
        goto error;

    /* Make a copy of the datatype obtained and save it in the table structure.
       It will be closed when the table is closed */
    if ((table->type_id = H5Tcopy(type_id)) < 0)
        goto error;

    /* Close the disk datatype */
    if (H5Tclose(type_id) < 0)
        goto error;
    type_id = H5I_INVALID_HID;

    /* Initialize the current record pointer */
    if ((H5PT_create_index(table)) < 0)
        goto error;

    /* Get number of records in table */
    if ((space_id = H5Dget_space(table->dset_id)) < 0)
        goto error;
    if (H5Sget_simple_extent_dims(space_id, dims, NULL) < 0)
        goto error;
    if (H5Sclose(space_id) < 0)
        goto error;
    space_id = H5I_INVALID_HID;

    table->size = dims[0];

    /* Get an ID for this table */
    ret_value = H5Iregister(H5PT_ptable_id_type, table);

    if (ret_value != H5I_INVALID_HID)
        H5PT_ptable_count++;
    else
        H5PT_close(table);

    return ret_value;

error:
    if (type_id != H5I_INVALID_HID)
        H5Dclose(type_id);
    if (space_id != H5I_INVALID_HID)
        H5Sclose(space_id);
    if (table) {
        if (table->type_id != H5I_INVALID_HID)
            H5Tclose(table->type_id);
        if (table->dset_id != H5I_INVALID_HID)
            H5Dclose(table->dset_id);
        HDfree(table);
    }

    return ret_value;
} /* H5PTopen */

/*-------------------------------------------------------------------------
 * Function: H5PT_free_id
 *
 * Purpose: Free an id.  Callback for H5Iregister_type.
 *
 * Return: Success: SUCCEED, Failure: N/A
 *-------------------------------------------------------------------------
 */
static herr_t
H5PT_free_id(void *id)
{
    HDfree(id);
    return SUCCEED;
}

/*-------------------------------------------------------------------------
 * Function: H5PT_close
 *
 * Purpose: Closes a table (i.e. cleans up all open resources used by a
 *          table).
 *
 * Return: Success: SUCCEED, Failure: FAIL
 *
 * Programmer: Nat Furrer
 *             James Laird
 *
 * Date: March 10, 2004
 *
 * Comments:
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5PT_close(htbl_t *table)
{
    if (table == NULL)
        goto error;

    /* Close the dataset */
    if (H5Dclose(table->dset_id) < 0)
        goto error;

    /* Close the memory datatype */
    if (H5Tclose(table->type_id) < 0)
        goto error;

    HDfree(table);

    return SUCCEED;

error:
    if (table) {
        H5E_BEGIN_TRY
        H5Dclose(table->dset_id);
        H5Tclose(table->type_id);
        H5E_END_TRY
        HDfree(table);
    }
    return FAIL;
}

/*-------------------------------------------------------------------------
 * Function: H5PTclose
 *
 * Purpose: Closes a table (i.e. cleans up all open resources used by a
 *          table).
 *
 * Return: Success: SUCCEED, Failure: FAIL
 *
 * Programmer: Nat Furrer
 *             James Laird
 *
 * Date: April 21, 2004
 *
 * Comments:
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5PTclose(hid_t table_id)
{
    htbl_t *table;

    /* Remove the ID from the library */
    if ((table = (htbl_t *)H5Iremove_verify(table_id, H5PT_ptable_id_type)) == NULL)
        goto error;

    /* If the library found the table, remove it */
    if (H5PT_close(table) < 0)
        goto error;

    /* One less packet table open */
    H5PT_ptable_count--;

    /* Remove the packet table type ID if no more packet */
    /* tables are open                                   */
    if (H5PT_ptable_count == 0) {
        H5Idestroy_type(H5PT_ptable_id_type);
        H5PT_ptable_id_type = H5I_UNINIT;
    }

    return SUCCEED;

error:
    return FAIL;
}

/*-------------------------------------------------------------------------
 *
 * Write functions
 *
 *-------------------------------------------------------------------------
 */

/*-------------------------------------------------------------------------
 * Function: H5PTappend
 *
 * Purpose: Appends packets to the end of a packet table
 *
 * Return: Success: SUCCEED, Failure: FAIL
 *
 * Programmer: Nat Furrer
 *             James Laird
 *
 * Date: March 12, 2004
 *
 * Comments:
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5PTappend(hid_t table_id, size_t nrecords, const void *data)
{
    htbl_t *table;

    /* Find the table struct from its ID */
    if ((table = (htbl_t *)H5Iobject_verify(table_id, H5PT_ptable_id_type)) == NULL)
        goto error;

    /* If we are asked to write 0 records, just do nothing */
    if (nrecords == 0)
        return SUCCEED;

    if ((H5TB_common_append_records(table->dset_id, table->type_id, nrecords, table->size, data)) < 0)
        goto error;

    /* Update table size */
    table->size += nrecords;
    return SUCCEED;

error:
    return FAIL;
}

/*-------------------------------------------------------------------------
 *
 * Read functions
 *
 *-------------------------------------------------------------------------
 */

/*-------------------------------------------------------------------------
 * Function: H5PTget_next
 *
 * Purpose: Reads packets starting at the current index and updates
 *          that index
 *
 * Return: Success: SUCCEED, Failure: FAIL
 *
 * Programmer: Nat Furrer
 *             James Laird
 *
 * Date: March 10, 2004
 *
 * Comments:
 *
 * Modifications:
 *
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5PTget_next(hid_t table_id, size_t nrecords, void *data)
{
    htbl_t *table;

    /* Find the table struct from its ID */
    if ((table = (htbl_t *)H5Iobject_verify(table_id, H5PT_ptable_id_type)) == NULL)
        goto error;

    /* If nrecords == 0, do nothing */
    if (nrecords == 0)
        return SUCCEED;

    if ((H5TB_common_read_records(table->dset_id, table->type_id, table->current_index, nrecords, table->size,
                                  data)) < 0)
        goto error;

    /* Update the current index */
    table->current_index += nrecords;
    return SUCCEED;

error:
    return FAIL;
}

/*-------------------------------------------------------------------------
 * Function: H5PTread_packets
 *
 * Purpose: Reads packets from anywhere in a packet table
 *
 * Return: Success: SUCCEED, Failure: FAIL
 *
 * Programmer: Nat Furrer
 *             James Laird
 *
 * Date: March 12, 2004
 *
 * Comments:
 *
 * Modifications:
 *
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5PTread_packets(hid_t table_id, hsize_t start, size_t nrecords, void *data)
{
    htbl_t *table;

    /* find the table struct from its ID */
    table = (htbl_t *)H5Iobject_verify(table_id, H5PT_ptable_id_type);
    if (table == NULL)
        goto error;

    /* If nrecords == 0, do nothing */
    if (nrecords == 0)
        return SUCCEED;

    if (H5TB_common_read_records(table->dset_id, table->type_id, start, nrecords, table->size, data) < 0)
        goto error;

    return SUCCEED;

error:
    return FAIL;
}

/*-------------------------------------------------------------------------
 *
 * Table attribute functions
 *
 *-------------------------------------------------------------------------
 */

/*-------------------------------------------------------------------------
 * Function: H5PT_create_index, H5PT_set_index, H5PT_get_index
 *
 * Purpose: Resets, sets, and gets the current record index for a packet table
 *
 * Return: Success: SUCCEED, Failure: FAIL
 *
 * Programmer: Nat Furrer
 *  		   James Laird
 *
 * Date: March 12, 2004
 *
 * Comments:
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5PT_create_index(htbl_t *table)
{
    if (table != NULL) {
        table->current_index = 0;
        return SUCCEED;
    }
    return FAIL;
}

static herr_t
H5PT_set_index(htbl_t *table, hsize_t pt_index)
{
    /* Ensure index is valid */
    if (table != NULL) {
        if (pt_index < table->size) {
            table->current_index = pt_index;
            return SUCCEED;
        }
    }
    return FAIL;
}

static herr_t
H5PT_get_index(htbl_t *table, hsize_t *pt_index)
{
    /* Ensure index is valid */
    if (table != NULL) {
        if (pt_index)
            *pt_index = table->current_index;
        return SUCCEED;
    }
    return FAIL;
}

/*-------------------------------------------------------------------------
 * Function: H5PTcreate_index, H5PTset_index, H5PTget_index
 *
 * Purpose: Resets, sets, and gets the current record index for a packet table
 *
 * Return: Success: SUCCEED, Failure: FAIL
 *
 * Programmer: Nat Furrer
 *             James Laird
 *
 * Date: April 23, 2004
 *
 * Comments:
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5PTcreate_index(hid_t table_id)
{
    htbl_t *table;

    /* find the table struct from its ID */
    if ((table = (htbl_t *)(htbl_t *)H5Iobject_verify(table_id, H5PT_ptable_id_type)) == NULL)
        return FAIL;

    return H5PT_create_index(table);
}

herr_t
H5PTset_index(hid_t table_id, hsize_t pt_index)
{
    htbl_t *table;

    /* find the table struct from its ID */
    if ((table = (htbl_t *)H5Iobject_verify(table_id, H5PT_ptable_id_type)) == NULL)
        return FAIL;

    return H5PT_set_index(table, pt_index);
}

herr_t
H5PTget_index(hid_t table_id, hsize_t *pt_index)
{
    htbl_t *table;

    /* find the table struct from its ID */
    if ((table = (htbl_t *)H5Iobject_verify(table_id, H5PT_ptable_id_type)) == NULL)
        return FAIL;

    return H5PT_get_index(table, pt_index);
}

/*-------------------------------------------------------------------------
 *
 * Inquiry functions
 *
 *-------------------------------------------------------------------------
 */

/*-------------------------------------------------------------------------
 * Function: H5PTget_num_packets
 *
 * Purpose: Returns by reference the number of packets in the packet table
 *
 * Return: Success: SUCCEED, Failure: FAIL
 *
 * Programmer: Nat Furrer
 *             James Laird
 *
 * Date: March 12, 2004
 *
 * Comments:
 *
 * Modifications:
 *
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5PTget_num_packets(hid_t table_id, hsize_t *nrecords)
{
    htbl_t *table;

    /* find the table struct from its ID */
    if ((table = (htbl_t *)H5Iobject_verify(table_id, H5PT_ptable_id_type)) == NULL)
        goto error;

    if (nrecords)
        *nrecords = table->size;

    return SUCCEED;

error:
    return FAIL;
}

/*-------------------------------------------------------------------------
 * Function: H5PTis_valid
 *
 * Purpose: Validates a table identifier
 *
 * Return: Success: SUCCEED, Failure: FAIL
 *
 * Programmer: Nat Furrer
 *             James Laird
 *
 * Date: March 12, 2004
 *
 * Comments:
 *
 * Modifications:
 *
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5PTis_valid(hid_t table_id)
{
    /* find the table struct from its ID */
    if (H5Iobject_verify(table_id, H5PT_ptable_id_type) == NULL)
        return FAIL;

    return SUCCEED;
}

/*-------------------------------------------------------------------------
 * Function: H5PTis_varlen
 *
 * Purpose: Returns 1 if a table_id corresponds to a packet table of variable-
 *          length records or 0 for fixed-length records.
 *
 * Return: True: 1, False: 0, Failure: FAIL
 *
 * Programmer: Nat Furrer
 *             James Laird
 *
 * Date: April 14, 2004
 *
 * Comments:
 *
 * Modifications:
 *
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5PTis_varlen(hid_t table_id)
{
    H5T_class_t type;
    htbl_t *    table;

    /* find the table struct from its ID */
    if ((table = (htbl_t *)H5Iobject_verify(table_id, H5PT_ptable_id_type)) == NULL)
        goto error;

    if ((type = H5Tget_class(table->type_id)) == H5T_NO_CLASS)
        goto error;

    if (type == H5T_VLEN)
        return 1;
    else
        return 0;

error:
    return FAIL;
}

/*-------------------------------------------------------------------------
 *
 * Memory Management functions
 *
 *-------------------------------------------------------------------------
 */

/*-------------------------------------------------------------------------
 * Function: H5PTfree_vlen_buff
 *
 * Purpose: Frees memory used when reading from a variable length packet
 *          table.
 *
 * Return: Success: SUCCEED, Failure: FAIL
 *          -2 if memory was reclaimed but another error occurred
 *
 * Programmer: Nat Furrer
 *             James Laird
 *
 * Date: April 12, 2004
 *
 * Comments:
 *
 * Modifications:
 *
 *
 *-------------------------------------------------------------------------
 */

herr_t
H5PTfree_vlen_buff(hid_t table_id, size_t _bufflen, void *buff)
{
    hid_t   space_id = H5I_INVALID_HID;
    htbl_t *table;
    hsize_t bufflen = _bufflen;
    herr_t  ret_value;

    /* find the table struct from its ID */
    if ((table = (htbl_t *)H5Iobject_verify(table_id, H5PT_ptable_id_type)) == NULL)
        goto error;

    if ((space_id = H5Screate_simple(1, &bufflen, NULL)) < 0)
        goto error;

    /* Free the memory.  If this succeeds, ret_value should be 0. */
    if ((ret_value = H5Treclaim(table->type_id, space_id, H5P_DEFAULT, buff)) < 0)
        goto error;

    /* If the dataspace cannot be closed, return -2 to indicate that memory */
    /* was freed successfully but an error still occurred. */
    if (H5Sclose(space_id) < 0)
        return -2;

    return ret_value;

error:
    H5E_BEGIN_TRY
    H5Sclose(space_id);
    H5E_END_TRY
    return FAIL;
} /* H5PTfree_vlen_buff */

/*-------------------------------------------------------------------------
 *
 * Accessor functions
 *
 *-------------------------------------------------------------------------
 */
/*-------------------------------------------------------------------------
 * Function: H5PTget_dataset
 *
 * Purpose: Returns the backend dataset of this packet table
 *
 * Return: Success: SUCCEED, Failure: FAIL
 *
 * Programmer: User's patch 0003, HDFFV-8623. -BMR
 *
 * Date: Feb 10, 2016
 *
 * Comments:
 *
 * Modifications:
 *
 *
 *-------------------------------------------------------------------------
 */
hid_t
H5PTget_dataset(hid_t table_id)
{
    htbl_t *table;
    hid_t   ret_value = H5I_INVALID_HID;

    /* find the table struct from its ID */
    if ((table = (htbl_t *)H5Iobject_verify(table_id, H5PT_ptable_id_type)) == NULL)
        goto error;

    ret_value = table->dset_id;

error:

    return ret_value;
}

/*-------------------------------------------------------------------------
 * Function: H5PTget_type
 *
 * Purpose: Returns the backend type of this packet table
 *
 * Return: Success: datatype ID, Failure: H5I_INVALID_HID
 *
 * Programmer: User's patch 0003, HDFFV-8623. -BMR
 *
 * Date: Feb 10, 2016
 *
 * Comments:
 *
 * Modifications:
 *
 *
 *-------------------------------------------------------------------------
 */
hid_t
H5PTget_type(hid_t table_id)
{
    htbl_t *table;
    hid_t   ret_value = H5I_INVALID_HID;

    /* find the table struct from its ID */
    if ((table = (htbl_t *)H5Iobject_verify(table_id, H5PT_ptable_id_type)) == NULL)
        goto error;

    ret_value = table->type_id;

error:

    return ret_value;
}