path: root/src/H5P.c

/****************************************************************************
* NCSA HDF                                                                 *
* Software Development Group                                               *
* National Center for Supercomputing Applications                          *
* University of Illinois at Urbana-Champaign                               *
* 605 E. Springfield, Champaign IL 61820                                   *
*                                                                          *
* For conditions of distribution and use, see the accompanying             *
* hdf/COPYING file.                                                        *
*                                                                          *
****************************************************************************/

#ifdef RCSID
static char             RcsId[] = "@(#)$Revision$";
#endif

/* $Id$ */

#include <stdarg.h>

/* Private header files */
#include <H5private.h>          /* Generic Functions                      */
#include <H5Aprivate.h>         /* Atoms                          */
#include <H5Bprivate.h>         /* B-tree subclass names          */
#include <H5Pprivate.h>         /* Template information           */
#include <H5Dprivate.h>         /* Datasets                               */
#include <H5Eprivate.h>         /* Error handling                 */
#include <H5MMprivate.h>        /* Memory management                      */

#define PABLO_MASK      H5P_mask

/* Is the interface initialized? */
static hbool_t          interface_initialize_g = FALSE;
#define INTERFACE_INIT H5P_init_interface
static herr_t           H5P_init_interface(void);

/* PRIVATE PROTOTYPES */
static void             H5P_term_interface(void);

/*--------------------------------------------------------------------------
NAME
   H5P_init_interface -- Initialize interface-specific information
USAGE
    herr_t H5P_init_interface()
   
RETURNS
   SUCCEED/FAIL
DESCRIPTION
    Initializes any interface-specific data or routines.

--------------------------------------------------------------------------*/
static herr_t
H5P_init_interface(void)
{
    herr_t                  ret_value = SUCCEED;
    intn                    i;
    herr_t                  status;

    FUNC_ENTER(H5P_init_interface, FAIL);

    /*
     * Make sure the file creation and file access default templates are
     * initialized since this might be done at run-time instead of compile
     * time.
     */
    if (H5F_init_interface ()<0) {
	HRETURN_ERROR (H5E_INTERNAL, H5E_CANTINIT, FAIL,
		       "unable to initialize H5F and H5P interfaces");
    }

    assert(H5P_NCLASSES <= H5_TEMPLATE_MAX - H5_TEMPLATE_0);

    /*
     * Initialize the mappings between template classes and atom groups. We
     * keep the two separate because template classes are publicly visible but
     * atom groups aren't.
     */
    for (i = 0; i < H5P_NCLASSES; i++) {
        status = H5A_init_group((group_t)(H5_TEMPLATE_0 +i),
				H5A_TEMPID_HASHSIZE, 0, NULL);
        if (status < 0) ret_value = FAIL;
    }
    if (ret_value < 0) {
        HRETURN_ERROR(H5E_ATOM, H5E_CANTINIT, FAIL,
                      "unable to initialize atom group");
    }
    
    /*
     * Register cleanup function.
     */
    if (H5_add_exit(H5P_term_interface) < 0) {
        HRETURN_ERROR(H5E_INTERNAL, H5E_CANTINIT, FAIL,
                      "unable to install atexit function");
    }
    
    FUNC_LEAVE(ret_value);
}

/*--------------------------------------------------------------------------
 NAME
    H5P_term_interface
 PURPOSE
    Terminate various H5P objects
 USAGE
    void H5P_term_interface()
 RETURNS
    SUCCEED/FAIL
 DESCRIPTION
    Release the atom group and any other resources allocated.
 GLOBAL VARIABLES
 COMMENTS, BUGS, ASSUMPTIONS
     Can't report errors...
 EXAMPLES
 REVISION LOG
--------------------------------------------------------------------------*/
static void
H5P_term_interface(void)
{
    intn                    i;

    for (i = 0; i < H5P_NCLASSES; i++) {
        H5A_destroy_group((group_t)(H5_TEMPLATE_0 + i));
    }
}

/*--------------------------------------------------------------------------
 NAME
    H5Pcreate
 PURPOSE
    Returns a copy of the default template for some class of templates.
 USAGE
    herr_t H5Pcreate (type)
        H5P_class_t type;       IN: Template class whose default is desired.
 RETURNS
    Template ID or FAIL
 
 ERRORS
    ARGS      BADVALUE      Unknown template class. 
    ATOM      CANTINIT      Can't register template. 
    INTERNAL  UNSUPPORTED   Not implemented yet. 

 DESCRIPTION
    Returns a copy of the default template for some class of templates.
--------------------------------------------------------------------------*/
hid_t
H5Pcreate(H5P_class_t type)
{
    hid_t                   ret_value = FAIL;
    void                   *tmpl = NULL;

    FUNC_ENTER(H5Pcreate, FAIL);

    /* Allocate a new template and initialize it with default values */
    switch (type) {
    case H5P_FILE_CREATE:
	tmpl = H5MM_xmalloc(sizeof(H5F_create_t));
        memcpy(tmpl, &H5F_create_dflt, sizeof(H5F_create_t));
        break;

    case H5P_FILE_ACCESS:
        tmpl = H5MM_xmalloc(sizeof(H5F_access_t));
        memcpy(tmpl, &H5F_access_dflt, sizeof(H5F_access_t));
        break;

    case H5P_DATASET_CREATE:
        tmpl = H5MM_xmalloc(sizeof(H5D_create_t));
        memcpy(tmpl, &H5D_create_dflt, sizeof(H5D_create_t));
        break;

    case H5P_DATASET_XFER:
        tmpl = H5MM_xmalloc(sizeof(H5D_xfer_t));
        memcpy(tmpl, &H5D_xfer_dflt, sizeof(H5D_xfer_t));
        break;

    default:
        HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL,
                      "unknown template class");
    }

    /* Atomize the new template */
    if ((ret_value = H5P_create(type, tmpl)) < 0) {
        HRETURN_ERROR(H5E_ATOM, H5E_CANTINIT, FAIL,
                      "can't register template");
    }
    FUNC_LEAVE(ret_value);
}

/*-------------------------------------------------------------------------
 * Function:    H5P_create
 *
 * Purpose:     Given a pointer to some template struct, atomize the template
 *              and return its ID. The template memory is not copied, so the
 *              caller should not free it; it will be freed by H5P_release().
 *
 * Return:      Success:        A new template ID.
 *
 *              Failure:        FAIL
 *
 * Programmer:  Robb Matzke
 *              Wednesday, December  3, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
hid_t
H5P_create(H5P_class_t type, void *tmpl)
{
    hid_t	ret_value = FAIL;

    FUNC_ENTER(H5P_create, FAIL);

    /* check args */
    assert(type >= 0 && type < H5P_NCLASSES);
    assert(tmpl);

    /* Atomize the new template */
    if ((ret_value=H5A_register((group_t)(H5_TEMPLATE_0+type), tmpl)) < 0) {
        HRETURN_ERROR(H5E_ATOM, H5E_CANTINIT, FAIL,
                      "can't register template");
    }
    
    FUNC_LEAVE(ret_value);
}

/*--------------------------------------------------------------------------
 NAME
    H5Pclose
 PURPOSE
    Release access to a template object.
 USAGE
    herr_t H5Pclose(oid)
        hid_t oid;       IN: Template object to release access to
 RETURNS
    SUCCEED/FAIL
 DESCRIPTION
        This function releases access to a template object
--------------------------------------------------------------------------*/
herr_t
H5Pclose(hid_t tid)
{
    H5P_class_t		type;
    void                *tmpl = NULL;

    FUNC_ENTER(H5Pclose, FAIL);

    /* Check arguments */
    if ((type=H5Pget_class (tid))<0 ||
	NULL==(tmpl=H5A_object (tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list");
    }
	
    /*
     * Chuck the object!  When the reference count reaches zero then
     * H5A_dec_ref() removes it from the group and we should free it.  The
     * free function is not registered as part of the group because it takes
     * an extra argument.
     */
    if (0==H5A_dec_ref(tid)) H5P_close (type, tmpl);

    FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5P_close
 *
 * Purpose:	Closes a template and frees the memory associated with the
 *		template.
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Wednesday, February 18, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5P_close (H5P_class_t type, void *tmpl)
{
    H5F_access_t	*fa_list = (H5F_access_t*)tmpl;
    
    FUNC_ENTER (H5P_close, FAIL);

    /* Check args */
    if (!tmpl) HRETURN (SUCCEED);

    /* Some templates may need to do special things */
    switch (type) {
    case H5P_FILE_ACCESS:
	switch (fa_list->driver) {
	case H5F_LOW_ERROR:
	case H5F_LOW_SEC2:
	case H5F_LOW_STDIO:
	case H5F_LOW_CORE:
	    /* Nothing to do */
	    break;

	case H5F_LOW_MPI:
#ifdef LATER
	    /* Need to free the COMM and INFO objects too. */
#endif
	    break;

	case H5F_LOW_SPLIT:
	    /* Free member info */
	    fa_list->driver = H5F_LOW_ERROR; /*prevent cycles*/
	    H5P_close (H5P_FILE_ACCESS, fa_list->u.split.meta_access);
	    H5P_close (H5P_FILE_ACCESS, fa_list->u.split.raw_access);
	    H5MM_xfree (fa_list->u.split.meta_ext);
	    H5MM_xfree (fa_list->u.split.raw_ext);
	    break;

	case H5F_LOW_FAMILY:
	    /* Free member info */
	    H5P_close (H5P_FILE_ACCESS, fa_list->u.fam.memb_access);
	    break;
	}
	break;
	
    case H5P_FILE_CREATE:
    case H5P_DATASET_CREATE:
    case H5P_DATASET_XFER:
	/*nothing to do*/
	break;

    default:
	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL,
		       "unknown property list class");
    }

    /* Free the template struct and return */
    H5MM_xfree(tmpl);
    FUNC_LEAVE(SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:    H5Pget_class
 *
 * Purpose:     Returns the class identifier for a template.
 *
 * Return:      Success:        A template class
 *
 *              Failure:        H5P_NO_CLASS (-1)
 *
 * Programmer:  Robb Matzke
 *              Wednesday, December  3, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
H5P_class_t
H5Pget_class(hid_t tid)
{
    group_t                 group;
    H5P_class_t             ret_value = H5P_NO_CLASS;

    FUNC_ENTER(H5Pget_class, H5P_NO_CLASS);

    if ((group = H5A_group(tid)) < 0 ||
#ifndef NDEBUG
        group >= H5_TEMPLATE_MAX ||
#endif
        group < H5_TEMPLATE_0) {
        HRETURN_ERROR(H5E_ATOM, H5E_BADATOM, H5P_NO_CLASS, "not a template");
    }
    ret_value = (H5P_class_t)(group - H5_TEMPLATE_0);
    FUNC_LEAVE(ret_value);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pget_version
 *
 * Purpose:     Retrieves version information for various parts of a file.
 *
 *              BOOT:           The file boot block.
 *              HEAP:           The global heap.
 *              FREELIST:       The global free list.
 *              STAB:           The root symbol table entry.
 *              SHHDR:          Shared object headers.
 *
 *              Any (or even all) of the output arguments can be null
 *              pointers.
 *
 * Return:      Success:        SUCCEED, version information is returned
 *                              through the arguments.
 *
 *              Failure:        FAIL
 *
 * Programmer:  Robb Matzke
 *              Wednesday, January  7, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pget_version(hid_t tid, int *boot /*out */ , int *heap /*out */ ,
         int *freelist /*out */ , int *stab /*out */ , int *shhdr /*out */ )
{
    H5F_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pget_version, FAIL);

    /* Check arguments */
    if (H5P_FILE_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "not a file creation template");
    }
    /* Get values */
    if (boot)
        *boot = tmpl->bootblock_ver;
    if (heap)
        *heap = tmpl->smallobject_ver;
    if (freelist)
        *freelist = tmpl->freespace_ver;
    if (stab)
        *stab = tmpl->objectdir_ver;
    if (shhdr)
        *shhdr = tmpl->sharedheader_ver;

    FUNC_LEAVE(SUCCEED);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pset_userblock
 *
 * Purpose:     Sets the userblock size field of a file creation template.
 *
 * Return:      Success:        SUCCEED
 *
 *              Failure:        FAIL
 *
 * Programmer:  Robb Matzke
 *              Tuesday, January  6, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pset_userblock(hid_t tid, size_t size)
{
    intn                    i;
    H5F_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pset_userblock, FAIL);

    /* Check arguments */
    if (H5P_FILE_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "not a file creation template");
    }
    for (i = 8; i < 8 * sizeof(int); i++) {
        uintn                   p2 = 8 == i ? 0 : 1 << i;
        if (size == p2)
            break;
    }
    if (i >= 8 * sizeof(int)) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL,
                      "userblock size is not valid");
    }
    /* Set value */
    tmpl->userblock_size = size;

    FUNC_LEAVE(SUCCEED);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pget_userblock
 *
 * Purpose:     Queries the size of a user block in a file creation template.
 *
 * Return:      Success:        SUCCEED, size returned through SIZE argument.
 *
 *              Failure:        FAIL
 *
 * Programmer:  Robb Matzke
 *              Wednesday, January  7, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pget_userblock(hid_t tid, size_t *size)
{
    H5F_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pget_userblock, FAIL);

    /* Check args */
    if (H5P_FILE_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "not a file creation template");
    }
    /* Get value */
    if (size)
        *size = tmpl->userblock_size;

    FUNC_LEAVE(SUCCEED);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pset_sizes
 *
 * Purpose:     Sets file size-of addresses and sizes.  TEMPLATE
 *              should be a file creation template.  A value of zero causes
 *              the property to not change.
 *
 * Return:      Success:        SUCCEED
 *
 *              Failure:        FAIL
 *
 * Programmer:  Robb Matzke
 *              Tuesday, January  6, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pset_sizes(hid_t tid, size_t sizeof_addr, size_t sizeof_size)
{
    H5F_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pset_sizeof_addr, FAIL);

    /* Check arguments */
    if (H5P_FILE_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "not a file creation template");
    }
    if (sizeof_addr) {
        if (sizeof_addr != 2 && sizeof_addr != 4 &&
            sizeof_addr != 8 && sizeof_addr != 16) {
            HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL,
                          "file haddr_t size is not valid");
        }
    }
    if (sizeof_size) {
        if (sizeof_size != 2 && sizeof_size != 4 &&
            sizeof_size != 8 && sizeof_size != 16) {
            HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL,
                          "file size_t size is not valid");
        }
    }
    /* Set value */
    if (sizeof_addr)
        tmpl->sizeof_addr = sizeof_addr;
    if (sizeof_size)
        tmpl->sizeof_size = sizeof_size;

    FUNC_LEAVE(SUCCEED);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pget_sizes
 *
 * Purpose:     Returns the size of address and size quantities stored in a
 *              file according to a file creation template.  Either (or even
 *              both) SIZEOF_ADDR and SIZEOF_SIZE may be null pointers.
 *
 * Return:      Success:        SUCCEED, sizes returned through arguments.
 *
 *              Failure:        FAIL
 *
 * Programmer:  Robb Matzke
 *              Wednesday, January  7, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pget_sizes(hid_t tid,
             size_t *sizeof_addr /*out */ , size_t *sizeof_size /*out */ )
{
    H5F_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pget_sizes, FAIL);

    /* Check args */
    if (H5P_FILE_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "not a file creation template");
    }
    /* Get values */
    if (sizeof_addr)
        *sizeof_addr = tmpl->sizeof_addr;
    if (sizeof_size)
        *sizeof_size = tmpl->sizeof_size;

    FUNC_LEAVE(SUCCEED);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pset_sym_k
 *
 * Purpose:     IK is one half the rank of a tree that stores a symbol
 *              table for a group.  Internal nodes of the symbol table are on
 *              average 75% full.  That is, the average rank of the tree is
 *              1.5 times the value of IK.
 *
 *              LK is one half of the number of symbols that can be stored in
 *              a symbol table node.  A symbol table node is the leaf of a
 *              symbol table tree which is used to store a group.  When
 *              symbols are inserted randomly into a group, the group's
 *              symbol table nodes are 75% full on average.  That is, they
 *              contain 1.5 times the number of symbols specified by LK.
 *
 *              Either (or even both) of IK and LK can be zero in which case
 *              that value is left unchanged.
 *
 * Return:      Success:        SUCCEED
 *
 *              Failure:        FAIL
 *
 * Programmer:  Robb Matzke
 *              Tuesday, January  6, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pset_sym_k(hid_t tid, int ik, int lk)
{
    H5F_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pset_sym_k, FAIL);

    /* Check arguments */
    if (H5P_FILE_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "not a file creation template");
    }
    /* Set values */
    if (ik > 0) {
        tmpl->btree_k[H5B_SNODE_ID] = ik;
    }
    if (lk > 0) {
        tmpl->sym_leaf_k = lk;
    }
    FUNC_LEAVE(SUCCEED);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pget_sym_k
 *
 * Purpose:     Retrieves the symbol table B-tree 1/2 rank (IK) and the
 *              symbol table leaf node 1/2 size (LK).  See H5Pset_sym_k() for
 *              details. Either (or even both) IK and LK may be null
 *              pointers.
 *
 * Return:      Success:        SUCCEED
 *
 *              Failure:        FAIL
 *
 * Programmer:  Robb Matzke
 *              Wednesday, January  7, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pget_sym_k(hid_t tid, int *ik /*out */ , int *lk /*out */ )
{
    H5F_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pget_sym_k, FAIL);

    /* Check arguments */
    if (H5P_FILE_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "not a file creation template");
    }
    /* Get values */
    if (ik)
        *ik = tmpl->btree_k[H5B_SNODE_ID];
    if (lk)
        *lk = tmpl->sym_leaf_k;

    FUNC_LEAVE(SUCCEED);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pset_istore_k
 *
 * Purpose:     IK is one half the rank of a tree that stores chunked raw
 *              data.  On average, such a tree will be 75% full, or have an
 *              average rank of 1.5 times the value of IK.
 *
 * Return:      Success:        SUCCEED
 *
 *              Failure:        FAIL
 *
 * Programmer:  Robb Matzke
 *              Tuesday, January  6, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pset_istore_k(hid_t tid, int ik)
{
    H5F_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pset_istore_k, FAIL);

    /* Check arguments */
    if (H5P_FILE_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "not a file creation template");
    }
    if (ik <= 0) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL,
                      "istore IK value must be positive");
    }
    /* Set value */
    tmpl->btree_k[H5B_ISTORE_ID] = ik;

    FUNC_LEAVE(SUCCEED);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pget_istore_k
 *
 * Purpose:     Queries the 1/2 rank of an indexed storage B-tree.  See
 *              H5Pset_istore_k() for details.  The argument IK may be the
 *              null pointer.
 *
 * Return:      Success:        SUCCEED, size returned through IK
 *
 *              Failure:        
 *
 * Programmer:  Robb Matzke
 *              Wednesday, January  7, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pget_istore_k(hid_t tid, int *ik /*out */ )
{
    H5F_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pget_istore_k, FAIL);

    /* Check arguments */
    if (H5P_FILE_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "not a file creation template");
    }
    /* Get value */
    if (ik)
        *ik = tmpl->btree_k[H5B_ISTORE_ID];

    FUNC_LEAVE(SUCCEED);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pset_layout
 *
 * Purpose:     Sets the layout of raw data in the file.
 *
 * Return:      Success:        SUCCEED
 *
 *              Failure:        FAIL
 *
 * Programmer:  Robb Matzke
 *              Tuesday, January  6, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pset_layout(hid_t tid, H5D_layout_t layout)
{
    H5D_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pset_layout, FAIL);

    /* Check arguments */
    if (H5P_DATASET_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "not a dataset creation template");
    }
    if (layout < 0 || layout >= H5D_NLAYOUTS) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL,
                      "raw data layout method is not valid");
    }
    /* Set value */
    tmpl->layout = layout;

    FUNC_LEAVE(SUCCEED);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pget_layout
 *
 * Purpose:     Retrieves layout type of a dataset creation template.
 *
 * Return:      Success:        The layout type
 *
 *              Failure:        H5D_LAYOUT_ERROR (-1, same as FAIL)
 *
 * Programmer:  Robb Matzke
 *              Wednesday, January  7, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
H5D_layout_t
H5Pget_layout(hid_t tid)
{
    H5D_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pget_layout, H5D_LAYOUT_ERROR);

    /* Check arguments */
    if (H5P_DATASET_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, H5D_LAYOUT_ERROR,
                      "not a dataset creation template");
    }
    FUNC_LEAVE(tmpl->layout);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pset_chunk
 *
 * Purpose:     Sets the number of dimensions and the size of each chunk to
 *              the values specified.  The dimensionality of the chunk should
 *              match the dimensionality of the data space.
 *
 *              As a side effect, the layout method is changed to
 *              H5D_CHUNKED.
 *
 * Return:      Success:        SUCCEED
 *
 *              Failure:        FAIL
 *
 * Programmer:  Robb Matzke
 *              Tuesday, January  6, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pset_chunk(hid_t tid, int ndims, const size_t dim[])
{
    int                     i;
    H5D_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pset_chunk, FAIL);

    /* Check arguments */
    if (H5P_DATASET_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "not a dataset creation template");
    }
    if (ndims <= 0) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL,
                      "chunk dimensionality must be positive");
    }
    if (ndims > NELMTS(tmpl->chunk_size)) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL,
                      "chunk dimensionality is too large");
    }
    if (!dim) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL,
                      "no chunk dimensions specified");
    }
    for (i = 0; i < ndims; i++) {
        if (dim[i] <= 0) {
            HRETURN_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL,
                          "all chunk dimensions must be positive");
        }
    }

    /* Set value */
    tmpl->layout = H5D_CHUNKED;
    tmpl->chunk_ndims = ndims;
    for (i = 0; i < ndims; i++)
        tmpl->chunk_size[i] = dim[i];

    FUNC_LEAVE(SUCCEED);
}

/*-------------------------------------------------------------------------
 * Function:    H5Pget_chunk
 *
 * Purpose:     Retrieves the chunk size of chunked layout.  The chunk
 *              dimensionality is returned and the chunk size in each
 *              dimension is returned through the DIM argument.  At most
 *              MAX_NDIMS elements of DIM will be initialized.
 *
 * Return:      Success:        Positive Chunk dimensionality.
 *
 *              Failure:        FAIL
 *
 * Programmer:  Robb Matzke
 *              Wednesday, January  7, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
int
H5Pget_chunk(hid_t tid, int max_ndims, size_t dim[] /*out */ )
{
    int                     i;
    H5D_create_t           *tmpl = NULL;

    FUNC_ENTER(H5Pget_chunk, FAIL);

    /* Check arguments */
    if (H5P_DATASET_CREATE != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
                      "not a dataset creation template");
    }
    if (H5D_CHUNKED != tmpl->layout) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL,
                      "not a chunked storage layout");
    }
    for (i = 0; i < tmpl->chunk_ndims && i < max_ndims && dim; i++) {
        dim[i] = tmpl->chunk_size[i];
    }

    FUNC_LEAVE(tmpl->chunk_ndims);
}


/*-------------------------------------------------------------------------
 * Function:	H5Pget_driver
 *
 * Purpose:	Return the ID of the low-level file driver.  TID should be a
 *		file access property list.
 *
 * Return:	Success:	A low-level driver ID
 *
 *		Failure:	H5F_LOW_ERROR (a negative value)
 *
 * Programmer:	Robb Matzke
 *              Thursday, February 26, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
H5F_driver_t
H5Pget_driver (hid_t tid)
{
    H5F_access_t	*tmpl = NULL;

    FUNC_ENTER (H5Pget_driver, H5F_LOW_ERROR);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class (tid) ||
	NULL == (tmpl = H5A_object (tid))) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, H5F_LOW_ERROR,
		       "not a file access property list");
    }

    FUNC_LEAVE (tmpl->driver);
}
    

/*-------------------------------------------------------------------------
 * Function:	H5Pset_stdio
 *
 * Purpose:	Set the low level file driver to use the functions declared
 *		in the stdio.h file: fopen(), fseek() or fseek64(), fread(),
 *		fwrite(), and fclose().
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Thursday, February 19, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pset_stdio (hid_t tid)
{
    H5F_access_t	*tmpl = NULL;
    
    FUNC_ENTER (H5Pset_stdio, FAIL);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
		      "not a file access template");
    }

    /* Set driver */
    tmpl->driver = H5F_LOW_STDIO;

    FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5Pget_stdio
 *
 * Purpose:	If the file access property list is set to the stdio driver
 *		then this function returns zero; otherwise it returns a
 *		negative value.  In the future, additional arguments may be
 *		added to this function to match those added to H5Pset_stdio().
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Thursday, February 26, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pget_stdio (hid_t tid)
{
    H5F_access_t	*tmpl = NULL;

    FUNC_ENTER (H5Pget_stdio, FAIL);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class (tid) ||
	NULL == (tmpl = H5A_object (tid))) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL,
		       "not a file access property list");
    }
    if (H5F_LOW_STDIO != tmpl->driver) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL,
		       "the stdio driver is not set");
    }

    FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5Pset_sec2
 *
 * Purpose:	Set the low-level file driver to use the functions declared
 *		in the unistd.h file: open(), lseek() or lseek64(), read(),
 *		write(), and close().
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Thursday, February 19, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pset_sec2 (hid_t tid)
{
    H5F_access_t	*tmpl = NULL;
    
    FUNC_ENTER (H5Pset_sec2, FAIL);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
		      "not a file access template");
    }

    /* Set driver */
    tmpl->driver = H5F_LOW_SEC2;

    FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5Pget_sec2
 *
 * Purpose:	If the file access property list is set to the sec2 driver
 *		then this function returns zero; otherwise it returns a
 *		negative value.  In the future, additional arguments may be
 *		added to this function to match those added to H5Pset_sec2().
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Thursday, February 26, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pget_sec2 (hid_t tid)
{
    H5F_access_t	*tmpl = NULL;

    FUNC_ENTER (H5Pget_sec2, FAIL);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class (tid) ||
	NULL == (tmpl = H5A_object (tid))) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL,
		       "not a file access property list");
    }
    if (H5F_LOW_SEC2 != tmpl->driver) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL,
		       "the sec2 driver is not set");
    }

    FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5Pset_core
 *
 * Purpose:	Set the low-level file driver to use malloc() and free().
 *		This driver is restricted to temporary files which are not
 *		larger than the amount of virtual memory available. The
 *		INCREMENT argument determines the file block size and memory
 *		will be allocated in multiples of INCREMENT bytes. A liberal
 *		INCREMENT results in fewer calls to realloc() and probably
 *		less memory fragmentation.
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Thursday, February 19, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pset_core (hid_t tid, size_t increment)
{
    H5F_access_t	*tmpl = NULL;
    
    FUNC_ENTER (H5Pset_core, FAIL);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
		      "not a file access template");
    }
    if (increment<1) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL,
		       "increment must be positive");
    }

    /* Set driver */
    tmpl->driver = H5F_LOW_CORE;
    tmpl->u.core.increment = increment;

    FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5Pget_core
 *
 * Purpose:	If the file access property list is set to the core driver
 *		then this function returns zero; otherwise it returns a
 *		negative value.  On success, the block size is returned
 *		through the INCREMENT argument if it isn't the null pointer.
 *		In the future, additional arguments may be added to this
 *		function to match those added to H5Pset_core().
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Thursday, February 26, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pget_core (hid_t tid, size_t *increment/*out*/)
{
    H5F_access_t	*tmpl = NULL;

    FUNC_ENTER (H5Pget_core, FAIL);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class (tid) ||
	NULL == (tmpl = H5A_object (tid))) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL,
		       "not a file access property list");
    }
    if (H5F_LOW_CORE != tmpl->driver) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL,
		       "the core driver is not set");
    }

    /* Return values */
    if (increment) {
	*increment = tmpl->u.core.increment;
    }
    
    FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5Pset_split
 *
 * Purpose:	Set the low-level driver to split meta data from raw data,
 *		storing meta data in one file and raw data in another file.
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Thursday, February 19, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pset_split (hid_t tid, const char *meta_ext, hid_t meta_tid,
	      const char *raw_ext, hid_t raw_tid)
{
    H5F_access_t	*tmpl = NULL;
    H5F_access_t	*meta_tmpl = NULL;
    H5F_access_t	*raw_tmpl = NULL;
    
    FUNC_ENTER (H5Pset_split, FAIL);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
		      "not a file access template");
    }
    if (H5P_DEFAULT!=meta_tid &&
	(H5P_FILE_ACCESS != H5Pget_class(meta_tid) ||
	 NULL == (tmpl = H5A_object(meta_tid)))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
		      "not a file access template");
    }
    if (H5P_DEFAULT!=raw_tid &&
	(H5P_FILE_ACCESS != H5Pget_class(raw_tid) ||
	 NULL == (tmpl = H5A_object(raw_tid)))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
		      "not a file access template");
    }

    /* Set driver */
    tmpl->driver = H5F_LOW_SPLIT;
    tmpl->u.split.meta_access = H5P_copy (H5P_FILE_ACCESS, meta_tmpl);
    tmpl->u.split.raw_access = H5P_copy (H5P_FILE_ACCESS, raw_tmpl);
    tmpl->u.split.meta_ext = H5MM_xstrdup (meta_ext);
    tmpl->u.split.raw_ext = H5MM_xstrdup (raw_ext);

    FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5Pget_split
 *
 * Purpose:	If the file access property list is set to the sec2 driver
 *		then this function returns zero; otherwise it returns a
 *		negative value.  On success, at most META_EXT_SIZE characters
 *		are copied to the META_EXT buffer if non-null and at most
 *		RAW_EXT_SIZE characters are copied to the RAW_EXT buffer if
 *		non-null.  If the actual extension is larger than the number
 *		of characters requested then the buffer will not be null
 *		terminated (that is, behavior like strncpy()).  In addition,
 *		if META_PROPERTIES and/or RAW_PROPERTIES are non-null then
 *		the file access property list of the meta file and/or raw
 *		file is copied and its OID returned through these arguments.
 *		If the meta file or raw file has no property list then an OID
 *		of FAIL (-1) is returned but the H5Pget_split() function
 *		still returns SUCCEED. In the future, additional arguments
 *		may be added to this function to match those added to
 *		H5Pset_sec2().
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Thursday, February 26, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pget_split (hid_t tid, size_t meta_ext_size, char *meta_ext/*out*/,
	      hid_t *meta_properties/*out*/, size_t raw_ext_size,
	      char *raw_ext/*out*/, hid_t *raw_properties/*out*/)
{
    H5F_access_t	*tmpl = NULL;

    FUNC_ENTER (H5Pget_split, FAIL);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class (tid) ||
	NULL == (tmpl = H5A_object (tid))) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL,
		       "not a file access property list");
    }
    if (H5F_LOW_SPLIT != tmpl->driver) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL,
		       "the split driver is not set");
    }

    /* Reset output args for error handling */
    if (meta_ext && meta_ext_size>0) *meta_ext = '\0';
    if (raw_ext && raw_ext_size>0) *raw_ext = '\0';
    if (meta_properties) *meta_properties = FAIL;
    if (raw_properties) *raw_properties = FAIL;

    /* Output arguments */
    if (meta_ext && meta_ext_size>0) {
	if (tmpl->u.split.meta_ext) {
	    strncpy (meta_ext, tmpl->u.split.meta_ext, meta_ext_size);
	} else {
	    strncpy (meta_ext, ".meta", meta_ext_size);
	}
    }
    if (raw_ext && raw_ext_size>0) {
	if (tmpl->u.split.raw_ext) {
	    strncpy (raw_ext, tmpl->u.split.raw_ext, raw_ext_size);
	} else {
	    strncpy (raw_ext, ".raw", raw_ext_size);
	}
    }
    if (meta_properties && tmpl->u.split.meta_access) {
	*meta_properties = H5P_create (H5P_FILE_ACCESS,
				       H5P_copy (H5P_FILE_ACCESS,
						 tmpl->u.split.meta_access));
    }
    if (raw_properties && tmpl->u.split.raw_access) {
	*raw_properties = H5P_create (H5P_FILE_ACCESS,
				      H5P_copy (H5P_FILE_ACCESS,
						tmpl->u.split.raw_access));
    }
    

    FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5Pset_family
 *
 * Purpose:	Sets the low-level driver to stripe the hdf5 address space
 *		across a family of files.
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Thursday, February 19, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pset_family (hid_t tid, hid_t memb_tid)
{
    
    H5F_access_t	*tmpl = NULL;
    H5F_access_t	*memb_tmpl = NULL;
    
    FUNC_ENTER (H5Pset_family, FAIL);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
		      "not a file access template");
    }
    if (H5P_DEFAULT!=memb_tid &&
	(H5P_FILE_ACCESS != H5Pget_class(memb_tid) ||
	 NULL == (tmpl = H5A_object(memb_tid)))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
		      "not a file access template");
    }

    /* Set driver */
    tmpl->driver = H5F_LOW_FAMILY;
    tmpl->u.fam.memb_access = H5P_copy (H5P_FILE_ACCESS, memb_tmpl);

    FUNC_LEAVE (SUCCEED);
}
    

/*-------------------------------------------------------------------------
 * Function:	H5Pget_family
 *
 * Purpose:	If the file access property list is set to the family driver
 *		then this function returns zero; otherwise it returns a
 *		negative value.  On success, if MEMB_TID is a non-null
 *		pointer it will be initialized with the OID of a copy of the
 *		file access template used for the family members.  If the
 *		family members have no file access template (that is, they
 *		are using the default values) then FAIL (-1) is returned for
 *		the member property list OID but the function still returns
 *		SUCCEED.  In the future, additional arguments may be added to
 *		this function to match those added to H5Pset_family().
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Thursday, February 26, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5Pget_family (hid_t tid, hid_t *memb_tid)
{
    H5F_access_t	*tmpl = NULL;

    FUNC_ENTER (H5Pget_family, FAIL);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class (tid) ||
	NULL == (tmpl = H5A_object (tid))) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL,
		       "not a file access property list");
    }
    if (H5F_LOW_FAMILY != tmpl->driver) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL,
		       "the family driver is not set");
    }

    /* Output args */
    if (memb_tid && tmpl->u.fam.memb_access) {
	*memb_tid = H5P_create (H5P_FILE_ACCESS,
				H5P_copy (H5P_FILE_ACCESS,
					  tmpl->u.fam.memb_access));
    } else if (memb_tid) {
	*memb_tid = FAIL;
    }
	
    FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:    H5Pset_mpi
 *
 * Signature:   herr_t H5Pset_mpi(hid_t tid, MPI_Comm comm, MPI_Info info,
 *                  uintn access_mode) 
 *
 * Purpose:     Store the access mode for MPIO call and the user supplied
 *              communicator and info in the access template which can then
 *              be used to open file.  This function is available only in the
 *              parallel HDF5 library and is not a collective function.
 *
 * Parameters:
 *              hid_t tid 
 *                  ID of template to modify 
 *              MPI_Comm comm 
 *      	    MPI communicator to be used for file open as defined in
 *                  MPI_FILE_OPEN of MPI-2.  This function  does not make a
 *                  duplicated communicator. Any modification to comm after
 *                  this function call returns may have undetermined effect
 *                  to the access template.  Users should call this function
 *                  again to setup the template.
 *              MPI_Info info 
 *      	    MPI info object to be used for file open as defined in
 *                  MPI_FILE_OPEN of MPI-2.  This function  does not make a
 *                  duplicated info. Any modification to info after
 *                  this function call returns may have undetermined effect
 *                  to the access template.  Users should call this function
 *                  again to setup the template.
 *              uintn access_mode 
 *      	    File data access modes: 
 *      		H5ACC_INDEPENDENT 
 *      	            Allow independent datasets access. 
 *      		H5ACC_COLLECTIVE 
 *      		    Allow only collective datasets access. 
 *           
 * Return:      Success:        SUCCEED
 *
 *              Failure:        FAIL
 *
 * Programmer:  Albert Cheng
 *              Feb 3, 1998
 *
 * Modifications:
 *
 * 	Robb Matzke, 18 Feb 1998
 *	Check all arguments before the template is updated so we don't leave
 *	the template in a bad state if something goes wrong.  Also, the
 *	template data type changed to allow more generality so all the
 *	mpi-related stuff is in the `u.mpi' member.  The `access_mode' will
 *	contain only mpi-related flags defined in H5Fpublic.h.
 *
 *-------------------------------------------------------------------------
 */
#ifdef HAVE_PARALLEL
herr_t
H5Pset_mpi (hid_t tid, MPI_Comm comm, MPI_Info info, uintn access_mode)
{
    H5F_access_t           *tmpl = NULL;
    MPI_Comm		    lcomm;
    int			    mrc;		/* MPI return code */

    FUNC_ENTER(H5Pset_mpi, FAIL);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class(tid) ||
        NULL == (tmpl = H5A_object(tid))) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL,
		      "not a file access template");
    }
    
    switch (access_mode){
    case H5ACC_INDEPENDENT:
    case H5ACC_COLLECTIVE:
	/* okay */
	break;

    default:
	HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL,
		       "invalid mpio access mode");
    }

#ifdef LATER
    /*
     * Need to verify comm and info contain sensible information.
     */
#endif


    /*
     * Everything looks good.  Now go ahead and modify the access template.
     */
    tmpl->driver = H5F_LOW_MPIO;
    tmpl->u.mpio.access_mode = access_mode;

    /*
     * Store a duplicate copy of comm so that user may freely modify comm
     * after this call.
     */
    if ((mrc = MPI_Comm_dup(comm, &lcomm)) != MPI_SUCCESS) {
        HRETURN_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL,
                      "failure to duplicate communicator");
    }
    tmpl->u.mpio.comm = comm;
    
#ifdef LATER
    /* Need to duplicate info too but don't know a quick way to do it now */
#endif
    tmpl->u.mpio.info = info;

    FUNC_LEAVE(SUCCEED);
}
#endif /*HAVE_PARALLEL*/


/*-------------------------------------------------------------------------
 * Function:	H5Pget_mpi
 *
 * Purpose:	If the file access property list is set to the mpi driver
 *		then this function returns zero; otherwise it returns a
 *		negative value.  In the future, additional arguments may be
 *		added to this function to match those added to H5Pset_mpi().
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *              Thursday, February 26, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
#ifdef HAVE_PARALLEL
herr_t
H5Pget_mpi (hid_t tid, MPI_Comm *comm, MPI_Info *info, uintn *access_mode)
{
    H5F_access_t	*tmpl = NULL;

    FUNC_ENTER (H5Pget_mpi, FAIL);

    /* Check arguments */
    if (H5P_FILE_ACCESS != H5Pget_class (tid) ||
	NULL == (tmpl = H5A_object (tid))) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADTYPE, FAIL,
		       "not a file access property list");
    }
    if (H5F_LOW_MPI != tmpl->driver) {
	HRETURN_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL,
		       "the mpi driver is not set");
    }

#ifndef LATER
    HRETURN_ERROR (H5E_IO, H5E_UNSUPPORTED, FAIL,
		   "not implemented yet");
#endif

    FUNC_LEAVE (SUCCEED);
}
#endif /*HAVE_PARALLEL*/


/*--------------------------------------------------------------------------
 NAME
    H5Pcopy
 PURPOSE
    Copy a template
 USAGE
    hid_t H5P_copy(tid)
        hid_t tid;        IN: Template object to copy
 RETURNS
    Returns template ID (atom) on success, FAIL on failure

 ERRORS
    ARGS      BADRANGE      Unknown template class. 
    ATOM      BADATOM       Can't unatomize template. 
    ATOM      CANTREGISTER  Register the atom for the new template. 
    INTERNAL  UNSUPPORTED   Dataset transfer properties are not implemented
                            yet. 
    INTERNAL  UNSUPPORTED   File access properties are not implemented yet. 

 DESCRIPTION
    This function creates a new copy of a template with all the same parameter
    settings.
--------------------------------------------------------------------------*/
hid_t
H5Pcopy(hid_t tid)
{
    const void             *tmpl = NULL;
    void                   *new_tmpl = NULL;
    H5P_class_t             type;
    hid_t                   ret_value = FAIL;
    group_t                 group;

    FUNC_ENTER(H5Pcopy, FAIL);

    /* Check args */
    if (NULL == (tmpl = H5A_object(tid)) ||
        (type = H5Pget_class(tid)) < 0 ||
        (group = H5A_group(tid)) < 0) {
        HRETURN_ERROR(H5E_ATOM, H5E_BADATOM, FAIL,
                      "can't unatomize template");
    }

    /* Copy it */
    if (NULL==(new_tmpl=H5P_copy (type, tmpl))) {
	HRETURN_ERROR (H5E_INTERNAL, H5E_CANTINIT, FAIL,
		       "unable to copy template");
    }

    /* Register the atom for the new template */
    if ((ret_value = H5A_register(group, new_tmpl)) < 0) {
        HRETURN_ERROR(H5E_ATOM, H5E_CANTREGISTER, FAIL,
                      "unable to atomize template pointer");
    }
    FUNC_LEAVE(ret_value);
}

/*-------------------------------------------------------------------------
 * Function:	H5P_copy
 *
 * Purpose:	Creates a new template and initializes it with some other
 *		template.
 *
 * Return:	Success:	Ptr to new template
 *
 *		Failure:	NULL
 *
 * Programmer:	Robb Matzke
 *              Tuesday, February  3, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
void *
H5P_copy (H5P_class_t type, const void *src)
{
    size_t	size;
    void	*dst = NULL;
    
    FUNC_ENTER (H5P_copy, NULL);
    
    /* How big is the template */
    switch (type) {
    case H5P_FILE_CREATE:
        size = sizeof(H5F_create_t);
        break;

    case H5P_FILE_ACCESS:
	size = sizeof(H5F_access_t);
	break;

    case H5P_DATASET_CREATE:
        size = sizeof(H5D_create_t);
        break;

    case H5P_DATASET_XFER:
        size = sizeof(H5D_xfer_t);
        break;

    default:
        HRETURN_ERROR(H5E_ARGS, H5E_BADRANGE, NULL,
                      "unknown template class");
    }

    /* Create the new template */
    dst = H5MM_xmalloc(size);
    HDmemcpy(dst, src, size);

    FUNC_LEAVE (dst);
}