path: root/src/H5Fint.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.                                                        *
 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

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

#define H5F_PACKAGE		/*suppress error about including H5Fpkg	  */

/* Interface initialization */
#define H5_INTERFACE_INIT_FUNC	H5F_init_interface


/***********/
/* Headers */
/***********/
#include "H5private.h"		/* Generic Functions			*/
#include "H5Aprivate.h"		/* Attributes				*/
#include "H5ACprivate.h"        /* Metadata cache                       */
#include "H5Dprivate.h"		/* Datasets				*/
#include "H5Eprivate.h"		/* Error handling		  	*/
#include "H5Fpkg.h"             /* File access				*/
#include "H5FDprivate.h"	/* File drivers				*/
#include "H5Gprivate.h"		/* Groups				*/
#include "H5Iprivate.h"		/* IDs			  		*/
#include "H5MFprivate.h"	/* File memory management		*/
#include "H5MMprivate.h"	/* Memory management			*/
#include "H5Pprivate.h"		/* Property lists			*/
#include "H5SMprivate.h"	/* Shared Object Header Messages	*/
#include "H5Tprivate.h"		/* Datatypes				*/

/* Predefined file drivers */
#include "H5FDcore.h"		/*temporary in-memory files		*/
#include "H5FDfamily.h"		/*family of files			*/
#include "H5FDlog.h"            /* sec2 driver with logging, for debugging */
#include "H5FDmpi.h"            /* MPI-based file drivers		*/
#include "H5FDmulti.h"		/*multiple files partitioned by mem usage */
#include "H5FDsec2.h"		/*Posix unbuffered I/O			*/
#include "H5FDstdio.h"		/* Standard C buffered I/O		*/
#ifdef H5_HAVE_WINDOWS
#include "H5FDwindows.h"        /* Windows buffered I/O     */
#endif
#include "H5FDdirect.h"         /*Linux direct I/O			*/

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

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

/* Struct only used by functions H5F_get_objects and H5F_get_objects_cb */
typedef struct H5F_olist_t {
    H5I_type_t obj_type;        /* Type of object to look for */
    hid_t      *obj_id_list;    /* Pointer to the list of open IDs to return */
    size_t     *obj_id_count;   /* Number of open IDs */
    struct {
        hbool_t local;          /* Set flag for "local" file searches */
        union {
            H5F_file_t *shared; /* Pointer to shared file to look inside */
            const H5F_t *file;  /* Pointer to file to look inside */
        } ptr;
    } file_info;
    size_t     list_index;      /* Current index in open ID array */
    size_t     max_nobjs;       /* Maximum # of IDs to put into array */
} H5F_olist_t;


/********************/
/* Package Typedefs */
/********************/


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

static int H5F_get_objects_cb(void *obj_ptr, hid_t obj_id, void *key);
static herr_t H5F_build_actual_name(const H5F_t *f, const H5P_genplist_t *fapl,
    const char *name, char ** /*out*/ actual_name);/* Declare a free list to manage the H5F_t struct */


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


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


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

/* Declare a free list to manage the H5F_t struct */
H5FL_DEFINE(H5F_t);

/* Declare a free list to manage the H5F_file_t struct */
H5FL_DEFINE(H5F_file_t);


/*-------------------------------------------------------------------------
 * Function:	H5F_init_interface
 *
 * Purpose:	Initialize interface-specific information.
 *
 * Return:	Success:	non-negative
 *		Failure:	negative
 *
 * Programmer:	Robb Matzke
 *              Friday, November 20, 1998
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5F_init_interface(void)
{
    herr_t ret_value = SUCCEED;                 /* Return value */

    FUNC_ENTER_NOAPI_NOINIT_NOERR

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_init_interface() */


/*-------------------------------------------------------------------------
 * Function:	H5F_get_access_plist
 *
 * Purpose:	Returns a copy of the file access property list of the
 *		specified file.
 *
 *              NOTE: Make sure that, if you are going to overwrite
 *              information in the copied property list that was
 *              previously opened and assigned to the property list, then
 *              you must close it before overwriting the values.
 *
 * Return:	Success:	Object ID for a copy of the file access
 *				property list.
 *
 *		Failure:	FAIL
 *
 * Programmer:	Quincey Koziol
 *              Wednesday, May 25, 2005
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
hid_t
H5F_get_access_plist(H5F_t *f, hbool_t app_ref)
{
    H5P_genplist_t *new_plist;              /* New property list */
    H5P_genplist_t *old_plist;              /* Old property list */
    void		*driver_info=NULL;
    unsigned            efc_size = 0;
    hid_t		ret_value = SUCCEED;

    FUNC_ENTER_NOAPI(FAIL)

    /* Check args */
    HDassert(f);

    /* Make a copy of the default file access property list */
    if(NULL == (old_plist = (H5P_genplist_t *)H5I_object(H5P_LST_FILE_ACCESS_ID_g)))
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list")
    if((ret_value = H5P_copy_plist(old_plist, app_ref)) < 0)
	HGOTO_ERROR(H5E_INTERNAL, H5E_CANTINIT, FAIL, "can't copy file access property list")
    if(NULL == (new_plist = (H5P_genplist_t *)H5I_object(ret_value)))
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list")

    /* Copy properties of the file access property list */
    if(H5P_set(new_plist, H5F_ACS_META_CACHE_INIT_CONFIG_NAME, &(f->shared->mdc_initCacheCfg)) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set initial metadata cache resize config.")
    if(H5P_set(new_plist, H5F_ACS_DATA_CACHE_NUM_SLOTS_NAME, &(f->shared->rdcc_nslots)) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set data cache number of slots")
    if(H5P_set(new_plist, H5F_ACS_DATA_CACHE_BYTE_SIZE_NAME, &(f->shared->rdcc_nbytes)) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set data cache byte size")
    if(H5P_set(new_plist, H5F_ACS_PREEMPT_READ_CHUNKS_NAME, &(f->shared->rdcc_w0)) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set preempt read chunks")
    if(H5P_set(new_plist, H5F_ACS_ALIGN_THRHD_NAME, &(f->shared->threshold)) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set alignment threshold")
    if(H5P_set(new_plist, H5F_ACS_ALIGN_NAME, &(f->shared->alignment)) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set alignment")
    if(H5P_set(new_plist, H5F_ACS_GARBG_COLCT_REF_NAME, &(f->shared->gc_ref)) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set garbage collect reference")
    if(H5P_set(new_plist, H5F_ACS_META_BLOCK_SIZE_NAME, &(f->shared->meta_aggr.alloc_size)) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set metadata cache size")
    if(H5P_set(new_plist, H5F_ACS_SIEVE_BUF_SIZE_NAME, &(f->shared->sieve_buf_size)) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't sieve buffer size")
    if(H5P_set(new_plist, H5F_ACS_SDATA_BLOCK_SIZE_NAME, &(f->shared->sdata_aggr.alloc_size)) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set 'small data' cache size")
    if(H5P_set(new_plist, H5F_ACS_LATEST_FORMAT_NAME, &(f->shared->latest_format)) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set 'latest format' flag")
    if(f->shared->efc)
        efc_size = H5F_efc_max_nfiles(f->shared->efc);
    if(H5P_set(new_plist, H5F_ACS_EFC_SIZE_NAME, &efc_size) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't set elink file cache size")

    /*
     * Since we're resetting the driver ID and info, close them if they
     * exist in this new property list.
     */
    if(H5P_facc_close(ret_value, NULL) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTFREE, FAIL, "can't free the old driver information")

    /* Increment the reference count on the driver ID and insert it into the property list */
    if(H5I_inc_ref(f->shared->lf->driver_id, FALSE) < 0)
        HGOTO_ERROR(H5E_FILE, H5E_CANTINC, FAIL, "unable to increment ref count on VFL driver")
    if(H5P_set(new_plist, H5F_ACS_FILE_DRV_ID_NAME, &(f->shared->lf->driver_id)) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set file driver ID")

    /* Set the driver "info" in the property list */
    driver_info = H5FD_fapl_get(f->shared->lf);
    if(driver_info != NULL && H5P_set(new_plist, H5F_ACS_FILE_DRV_INFO_NAME, &driver_info) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set file driver info")

    /* Set the file close degree appropriately */
    if(f->shared->fc_degree == H5F_CLOSE_DEFAULT && H5P_set(new_plist, H5F_ACS_CLOSE_DEGREE_NAME, &(f->shared->lf->cls->fc_degree)) < 0) {
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set file close degree")
    } else if(f->shared->fc_degree != H5F_CLOSE_DEFAULT && H5P_set(new_plist, H5F_ACS_CLOSE_DEGREE_NAME, &(f->shared->fc_degree)) < 0) {
        HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set file close degree")
    }

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_get_access_plist() */


/*-------------------------------------------------------------------------
 * Function:    H5F_get_obj_count
 *
 * Purpose:	Private function return the number of opened object IDs
 *		(files, datasets, groups, datatypes) in the same file.
 *
 * Return:      SUCCEED on success, FAIL on failure.
 *
 * Programmer:  Raymond Lu
 *              Wednesday, Dec 5, 2001
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_get_obj_count(const H5F_t *f, unsigned types, hbool_t app_ref, size_t *obj_id_count_ptr)
{
    herr_t   ret_value = SUCCEED;

    FUNC_ENTER_NOAPI(FAIL)

    /* Sanity check */
    HDassert(obj_id_count_ptr);

    /* Perform the query */
    if((ret_value = H5F_get_objects(f, types, 0, NULL, app_ref, obj_id_count_ptr)) < 0)
        HGOTO_ERROR(H5E_INTERNAL, H5E_BADITER, FAIL, "H5F_get_objects failed")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_get_obj_count() */


/*-------------------------------------------------------------------------
 * Function:    H5F_get_obj_ids
 *
 * Purpose:     Private function to return a list of opened object IDs.
 *
 * Return:      Non-negative on success; can't fail.
 *
 * Programmer:  Raymond Lu
 *              Wednesday, Dec 5, 2001
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_get_obj_ids(const H5F_t *f, unsigned types, size_t max_objs, hid_t *oid_list, hbool_t app_ref, size_t *obj_id_count_ptr)
{
    herr_t ret_value = SUCCEED;              /* Return value */

    FUNC_ENTER_NOAPI(FAIL)

    /* Sanity check */
    HDassert(obj_id_count_ptr);

    /* Perform the query */
    if((ret_value = H5F_get_objects(f, types, max_objs, oid_list, app_ref, obj_id_count_ptr)) < 0)
        HGOTO_ERROR(H5E_INTERNAL, H5E_BADITER, FAIL, "H5F_get_objects failed")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_get_obj_ids() */


/*---------------------------------------------------------------------------
 * Function:	H5F_get_objects
 *
 * Purpose:	This function is called by H5F_get_obj_count or
 *		H5F_get_obj_ids to get number of object IDs and/or a
 *		list of opened object IDs (in return value).
 * Return:	Non-negative on success; Can't fail.
 *
 * Programmer:  Raymond Lu
 *              Wednesday, Dec 5, 2001
 *
 *---------------------------------------------------------------------------
 */
herr_t
H5F_get_objects(const H5F_t *f, unsigned types, size_t max_nobjs, hid_t *obj_id_list, hbool_t app_ref, size_t *obj_id_count_ptr)
{
    size_t obj_id_count=0;      /* Number of open IDs */
    H5F_olist_t olist;          /* Structure to hold search results */
    herr_t ret_value = SUCCEED; /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    /* Sanity check */
    HDassert(obj_id_count_ptr);

    /* Set up search information */
    olist.obj_id_list  = (max_nobjs==0 ? NULL : obj_id_list);
    olist.obj_id_count = &obj_id_count;
    olist.list_index   = 0;
    olist.max_nobjs   = max_nobjs;

    /* Determine if we are searching for local or global objects */
    if(types & H5F_OBJ_LOCAL) {
        olist.file_info.local = TRUE;
        olist.file_info.ptr.file = f;
    } /* end if */
    else {
        olist.file_info.local = FALSE;
        olist.file_info.ptr.shared = f ? f->shared : NULL;
    } /* end else */

    /* Iterate through file IDs to count the number, and put their
     * IDs on the object list.  */
    if(types & H5F_OBJ_FILE) {
        olist.obj_type = H5I_FILE;
        if(H5I_iterate(H5I_FILE, H5F_get_objects_cb, &olist, app_ref) < 0)
            HGOTO_ERROR(H5E_FILE, H5E_BADITER, FAIL, "iteration failed(1)")
    } /* end if */

    /* If the caller just wants to count the number of objects (OLIST.MAX_NOBJS is zero),
     * or the caller wants to get the list of IDs and the list isn't full,
     * search through dataset IDs to count number of datasets, and put their
     * IDs on the object list */
    if(!olist.max_nobjs || (olist.max_nobjs && olist.list_index<olist.max_nobjs)) { 
        if (types & H5F_OBJ_DATASET) {
            olist.obj_type = H5I_DATASET;
            if(H5I_iterate(H5I_DATASET, H5F_get_objects_cb, &olist, app_ref) < 0)
                HGOTO_ERROR(H5E_FILE, H5E_BADITER, FAIL, "iteration failed(2)")
        } /* end if */
    } 

    /* If the caller just wants to count the number of objects (OLIST.MAX_NOBJS is zero),
     * or the caller wants to get the list of IDs and the list isn't full,
     * search through group IDs to count number of groups, and put their
     * IDs on the object list */
    if(!olist.max_nobjs || (olist.max_nobjs && olist.list_index<olist.max_nobjs)) { 
        if(types & H5F_OBJ_GROUP) {
            olist.obj_type = H5I_GROUP;
            if(H5I_iterate(H5I_GROUP, H5F_get_objects_cb, &olist, app_ref) < 0)
                HGOTO_ERROR(H5E_FILE, H5E_BADITER, FAIL, "iteration failed(3)")
        } /* end if */
    } 

    /* If the caller just wants to count the number of objects (OLIST.MAX_NOBJS is zero),
     * or the caller wants to get the list of IDs and the list isn't full,
     * search through datatype IDs to count number of named datatypes, and put their
     * IDs on the object list */
    if(!olist.max_nobjs || (olist.max_nobjs && olist.list_index<olist.max_nobjs)) { 
        if(types & H5F_OBJ_DATATYPE) {
            olist.obj_type = H5I_DATATYPE;
            if(H5I_iterate(H5I_DATATYPE, H5F_get_objects_cb, &olist, app_ref) < 0)
                HGOTO_ERROR(H5E_FILE, H5E_BADITER, FAIL, "iteration failed(4)")
        } /* end if */
    } 

    /* If the caller just wants to count the number of objects (OLIST.MAX_NOBJS is zero),
     * or the caller wants to get the list of IDs and the list isn't full,
     * search through attribute IDs to count number of attributes, and put their
     * IDs on the object list */
    if(!olist.max_nobjs || (olist.max_nobjs && olist.list_index<olist.max_nobjs)) {
        if(types & H5F_OBJ_ATTR) {
            olist.obj_type = H5I_ATTR;
            if(H5I_iterate(H5I_ATTR, H5F_get_objects_cb, &olist, app_ref) < 0)
                HGOTO_ERROR(H5E_FILE, H5E_BADITER, FAIL, "iteration failed(5)")
        } /* end if */
    }
 
    /* Set the number of objects currently open */
    *obj_id_count_ptr = obj_id_count;

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_get_objects() */


/*-------------------------------------------------------------------------
 * Function:	H5F_get_objects_cb
 *
 * Purpose:	H5F_get_objects' callback function.  It verifies if an
 * 		object is in the file, and either count it or put its ID
 *		on the list.
 *
 * Return:      H5_ITER_STOP if the array of object IDs is filled up.
 *              H5_ITER_CONT otherwise.
 *
 * Programmer:  Raymond Lu
 *              Wednesday, Dec 5, 2001
 *
 *-------------------------------------------------------------------------
 */
static int
H5F_get_objects_cb(void *obj_ptr, hid_t obj_id, void *key)
{
    H5F_olist_t *olist = (H5F_olist_t *)key;    /* Alias for search info */
    int         ret_value = H5_ITER_CONT;    /* Return value */
    hbool_t     add_obj = FALSE;

    FUNC_ENTER_NOAPI_NOINIT

    HDassert(obj_ptr);
    HDassert(olist);

    /* Count file IDs */
    if(olist->obj_type == H5I_FILE) {
        if((olist->file_info.local &&
                        (!olist->file_info.ptr.file || (olist->file_info.ptr.file && (H5F_t*)obj_ptr == olist->file_info.ptr.file) ))
                ||  (!olist->file_info.local &&
                        ( !olist->file_info.ptr.shared || (olist->file_info.ptr.shared && ((H5F_t*)obj_ptr)->shared == olist->file_info.ptr.shared) ))) {
            add_obj = TRUE;
	}
    } /* end if */
    else { /* either count opened object IDs or put the IDs on the list */
        H5O_loc_t *oloc;        /* Group entry info for object */

    	switch(olist->obj_type) {
	    case H5I_ATTR:
	        oloc = H5A_oloc((H5A_t *)obj_ptr);
                break;

	    case H5I_GROUP:
	        oloc = H5G_oloc((H5G_t *)obj_ptr);
                break;

	    case H5I_DATASET:
	        oloc = H5D_oloc((H5D_t *)obj_ptr);
		break;

	    case H5I_DATATYPE:
                if(H5T_is_named((H5T_t*)obj_ptr)==TRUE)
                    oloc = H5T_oloc((H5T_t*)obj_ptr);
                else
                    oloc = NULL;
		break;

	    case H5I_UNINIT:
	    case H5I_BADID:
	    case H5I_FILE:
	    case H5I_DATASPACE:
	    case H5I_REFERENCE:
	    case H5I_VFL:
	    case H5I_GENPROP_CLS:
	    case H5I_GENPROP_LST:
	    case H5I_ERROR_CLASS:
	    case H5I_ERROR_MSG:
	    case H5I_ERROR_STACK:
	    case H5I_NTYPES:
            default:
                HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5_ITER_ERROR, "unknown data object")
	} /* end switch */

        if((olist->file_info.local &&
                    ( (!olist->file_info.ptr.file && olist->obj_type == H5I_DATATYPE && H5T_is_immutable((H5T_t *)obj_ptr) == FALSE)
                            || (!olist->file_info.ptr.file && olist->obj_type != H5I_DATATYPE)
                            || (oloc && oloc->file == olist->file_info.ptr.file)))
                || (!olist->file_info.local &&
                    ((!olist->file_info.ptr.shared && olist->obj_type == H5I_DATATYPE && H5T_is_immutable((H5T_t *)obj_ptr) == FALSE)
                            || (!olist->file_info.ptr.shared && olist->obj_type != H5I_DATATYPE)
                            || (oloc && oloc->file && oloc->file->shared == olist->file_info.ptr.shared)))) {
            add_obj = TRUE;
    	} /* end if */
    } /* end else */

    if(TRUE==add_obj) {
        /* Add the object's ID to the ID list, if appropriate */
        if(olist->obj_id_list) {
            olist->obj_id_list[olist->list_index] = obj_id;
	    olist->list_index++;
	} /* end if */

        /* Increment the number of open objects */
	if(olist->obj_id_count)
            (*olist->obj_id_count)++;

        /* Check if we've filled up the array.  Return H5_ITER_STOP only if
         * we have filled up the array. Otherwise return H5_ITER_CONT(RET_VALUE is
         * preset to H5_ITER_CONT) because H5I_iterate needs the return value of 
         * H5_ITER_CONT to continue the iteration. */
        if(olist->max_nobjs>0 && olist->list_index>=olist->max_nobjs)
            HGOTO_DONE(H5_ITER_STOP)  /* Indicate that the iterator should stop */
    }

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_get_objects_cb() */


/*-------------------------------------------------------------------------
 * Function:	H5F_is_hdf5
 *
 * Purpose:	Check the file signature to detect an HDF5 file.
 *
 * Bugs:	This function is not robust: it only uses the default file
 *		driver when attempting to open the file when in fact it
 *		should use all known file drivers.
 *
 * Return:	Success:	TRUE/FALSE
 *
 *		Failure:	Negative
 *
 * Programmer:	Unknown
 *
 * Modifications:
 *		Robb Matzke, 1999-08-02
 *		Rewritten to use the virtual file layer.
 *-------------------------------------------------------------------------
 */
htri_t
H5F_is_hdf5(const char *name)
{
    H5FD_t	*file = NULL;           /* Low-level file struct */
    haddr_t     sig_addr;               /* Addess of hdf5 file signature */
    htri_t	ret_value;              /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    /* Open the file at the virtual file layer */
    if(NULL == (file = H5FD_open(name, H5F_ACC_RDONLY, H5P_FILE_ACCESS_DEFAULT, HADDR_UNDEF)))
	HGOTO_ERROR(H5E_IO, H5E_CANTINIT, FAIL, "unable to open file")

    /* The file is an hdf5 file if the hdf5 file signature can be found */
    if(H5FD_locate_signature(file, H5AC_ind_dxpl_g, &sig_addr) < 0)
        HGOTO_ERROR(H5E_FILE, H5E_NOTHDF5, FAIL, "unable to locate file signature")
    ret_value = (HADDR_UNDEF != sig_addr);

done:
    /* Close the file */
    if(file)
        if(H5FD_close(file) < 0 && ret_value >= 0)
            HDONE_ERROR(H5E_IO, H5E_CANTCLOSEFILE, FAIL, "unable to close file")

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_is_hdf5() */


/*-------------------------------------------------------------------------
 * Function:	H5F_new
 *
 * Purpose:	Creates a new file object and initializes it.  The
 *		H5Fopen and H5Fcreate functions then fill in various
 *		fields.	 If SHARED is a non-null pointer then the shared info
 *		to which it points has the reference count incremented.
 *		Otherwise a new, empty shared info struct is created and
 *		initialized with the specified file access property list.
 *
 * Errors:
 *
 * Return:	Success:	Ptr to a new file struct.
 *
 *		Failure:	NULL
 *
 * Programmer:	Robb Matzke
 *		matzke@llnl.gov
 *		Jul 18 1997
 *
 *-------------------------------------------------------------------------
 */
H5F_t *
H5F_new(H5F_file_t *shared, unsigned flags, hid_t fcpl_id, hid_t fapl_id, H5FD_t *lf)
{
    H5F_t	*f = NULL, *ret_value;

    FUNC_ENTER_NOAPI_NOINIT

    if(NULL == (f = H5FL_CALLOC(H5F_t)))
	HGOTO_ERROR(H5E_FILE, H5E_NOSPACE, NULL, "can't allocate top file structure")
    f->file_id = -1;

    if(shared) {
        HDassert(lf == NULL);
	f->shared = shared;
    } /* end if */
    else {
        H5P_genplist_t *plist;          /* Property list */
        unsigned        efc_size;       /* External file cache size */
        size_t u;                       /* Local index variable */

        HDassert(lf != NULL);
        if(NULL == (f->shared = H5FL_CALLOC(H5F_file_t)))
            HGOTO_ERROR(H5E_FILE, H5E_NOSPACE, NULL, "can't allocate shared file structure")

        f->shared->flags = flags;
	f->shared->sohm_addr = HADDR_UNDEF;
	f->shared->sohm_vers = HDF5_SHAREDHEADER_VERSION;
        for(u = 0; u < NELMTS(f->shared->fs_addr); u++)
            f->shared->fs_addr[u] = HADDR_UNDEF;
	f->shared->accum.loc = HADDR_UNDEF;
        f->shared->lf = lf;

	/*
	 * Copy the file creation and file access property lists into the
	 * new file handle.  We do this early because some values might need
	 * to change as the file is being opened.
	 */
        if(NULL == (plist = (H5P_genplist_t *)H5I_object(fcpl_id)))
            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not property list")
        f->shared->fcpl_id = H5P_copy_plist(plist, FALSE);

        /* Get the FCPL values to cache */
        if(H5P_get(plist, H5F_CRT_ADDR_BYTE_NUM_NAME, &f->shared->sizeof_addr) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get byte number for address")
        if(H5P_get(plist, H5F_CRT_OBJ_BYTE_NUM_NAME, &f->shared->sizeof_size) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get byte number for object size")
        if(H5P_get(plist, H5F_CRT_SHMSG_NINDEXES_NAME, &f->shared->sohm_nindexes) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get number of SOHM indexes")
        HDassert(f->shared->sohm_nindexes < 255);

        /* Get the FAPL values to cache */
        if(NULL == (plist = (H5P_genplist_t *)H5I_object(fapl_id)))
            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not file access property list")
        if(H5P_get(plist, H5F_ACS_META_CACHE_INIT_CONFIG_NAME, &(f->shared->mdc_initCacheCfg)) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get initial metadata cache resize config")
        if(H5P_get(plist, H5F_ACS_DATA_CACHE_NUM_SLOTS_NAME, &(f->shared->rdcc_nslots)) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get data cache number of slots")
        if(H5P_get(plist, H5F_ACS_DATA_CACHE_BYTE_SIZE_NAME, &(f->shared->rdcc_nbytes)) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get data cache byte size")
        if(H5P_get(plist, H5F_ACS_PREEMPT_READ_CHUNKS_NAME, &(f->shared->rdcc_w0)) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get preempt read chunk")
        if(H5P_get(plist, H5F_ACS_ALIGN_THRHD_NAME, &(f->shared->threshold)) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get alignment threshold")
        if(H5P_get(plist, H5F_ACS_ALIGN_NAME, &(f->shared->alignment)) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get alignment")
        if(H5P_get(plist, H5F_ACS_GARBG_COLCT_REF_NAME,&(f->shared->gc_ref)) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get garbage collect reference")
        if(H5P_get(plist, H5F_ACS_SIEVE_BUF_SIZE_NAME, &(f->shared->sieve_buf_size)) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get sieve buffer size")
        if(H5P_get(plist, H5F_ACS_LATEST_FORMAT_NAME, &(f->shared->latest_format)) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get 'latest format' flag")
        if(H5P_get(plist, H5F_ACS_META_BLOCK_SIZE_NAME, &(f->shared->meta_aggr.alloc_size)) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get metadata cache size")
        f->shared->meta_aggr.feature_flag = H5FD_FEAT_AGGREGATE_METADATA;
        if(H5P_get(plist, H5F_ACS_SDATA_BLOCK_SIZE_NAME, &(f->shared->sdata_aggr.alloc_size)) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get 'small data' cache size")
        f->shared->sdata_aggr.feature_flag = H5FD_FEAT_AGGREGATE_SMALLDATA;
        if(H5P_get(plist, H5F_ACS_EFC_SIZE_NAME, &efc_size) < 0)
            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get elink file cache size")
        if(efc_size > 0)
            if(NULL == (f->shared->efc = H5F_efc_create(efc_size)))
                HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "can't create external file cache")

        /* Get the VFD values to cache */
        f->shared->maxaddr = H5FD_get_maxaddr(lf);
        if(!H5F_addr_defined(f->shared->maxaddr))
            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, NULL, "bad maximum address from VFD")
        if(H5FD_get_feature_flags(lf, &f->shared->feature_flags) < 0)
            HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "can't get feature flags from VFD")
        if(H5FD_get_fs_type_map(lf, f->shared->fs_type_map) < 0)
            HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "can't get free space type mapping from VFD")
        if(H5MF_init_merge_flags(f) < 0)
            HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "problem initializing free space merge flags")
        f->shared->tmp_addr = f->shared->maxaddr;
        /* Disable temp. space allocation for parallel I/O (for now) */
        /* (When we've arranged to have the relocated metadata addresses (and
         *      sizes) broadcast during the "end of epoch" metadata operations,
         *      this can be enabled - QAK)
         */
        /* (This should be disabled when the metadata journaling branch is
         *      merged into the trunk and journaling is enabled, at least until
         *      we make it work. - QAK)
         */
        f->shared->use_tmp_space = !H5F_HAS_FEATURE(f, H5FD_FEAT_HAS_MPI);

	/*
	 * Create a metadata cache with the specified number of elements.
	 * The cache might be created with a different number of elements and
	 * the access property list should be updated to reflect that.
	 */
	if(H5AC_create(f, &(f->shared->mdc_initCacheCfg)) < 0)
	    HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "unable to create metadata cache")

        /* Create the file's "open object" information */
        if(H5FO_create(f) < 0)
	    HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "unable to create open object data structure")

        /* Add new "shared" struct to list of open files */
        if(H5F_sfile_add(f->shared) < 0)
	    HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "unable to append to list of open files")
    } /* end else */

    f->shared->nrefs++;

    /* Create the file's "top open object" information */
    if(H5FO_top_create(f) < 0)
        HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "unable to create open object data structure")

    /* Set return value */
    ret_value = f;

done:
    if(!ret_value && f) {
	if(!shared) {
            /* Attempt to clean up some of the shared file structures */
            if(f->shared->efc)
                if(H5F_efc_destroy(f->shared->efc) < 0)
                    HDONE_ERROR(H5E_FILE, H5E_CANTRELEASE, NULL, "can't destroy external file cache")
            if(f->shared->fcpl_id > 0)
                if(H5I_dec_ref(f->shared->fcpl_id) < 0)
                    HDONE_ERROR(H5E_FILE, H5E_CANTDEC, NULL, "can't close property list")

            f->shared = H5FL_FREE(H5F_file_t, f->shared);
        } /* end if */
	f = H5FL_FREE(H5F_t, f);
    } /* end if */

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_new() */


/*-------------------------------------------------------------------------
 * Function:	H5F_dest
 *
 * Purpose:	Destroys a file structure.  This function flushes the cache
 *		but doesn't do any other cleanup other than freeing memory
 *		for the file struct.  The shared info for the file is freed
 *		only when its reference count reaches zero.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		matzke@llnl.gov
 *		Jul 18 1997
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_dest(H5F_t *f, hid_t dxpl_id, hbool_t flush)
{
    herr_t	   ret_value = SUCCEED;         /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    /* Sanity check */
    HDassert(f);
    HDassert(f->shared);

    if(1 == f->shared->nrefs) {
        H5F_io_info_t fio_info;             /* I/O info for operation */

        /* Flush at this point since the file will be closed.
         * Only try to flush the file if it was opened with write access, and if
         * the caller requested a flush.
         */
        if((f->shared->flags & H5F_ACC_RDWR) && flush)
            if(H5F_flush(f, dxpl_id, TRUE) < 0)
                HDONE_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush cache")

        /* Release the external file cache */
        if(f->shared->efc) {
            if(H5F_efc_destroy(f->shared->efc) < 0)
                HDONE_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "can't destroy external file cache")
            f->shared->efc = NULL;
        } /* end if */

        /* Release objects that depend on the superblock being initialized */
        if(f->shared->sblock) {
            /* Shutdown file free space manager(s) */
            /* (We should release the free space information now (before truncating
             *      the file and before the metadata cache is shut down) since the
             *      free space manager is holding some data structures in memory
             *      and also because releasing free space can shrink the file's
             *      'eoa' value)
             */
            if(H5F_ACC_RDWR & H5F_INTENT(f)) {
                if(H5MF_close(f, dxpl_id) < 0)
                    /* Push error, but keep going*/
                    HDONE_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "can't release file free space info")

                /* Flush the file again (if requested), as shutting down the
                 * free space manager may dirty some data structures again.
                 */
                if(flush)
                    if(H5F_flush(f, dxpl_id, TRUE) < 0)
                        /* Push error, but keep going*/
                        HDONE_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush cache")
            } /* end if */

            /* Unpin the superblock, since we're about to destroy the cache */
            if(H5AC_unpin_entry(f->shared->sblock) < 0)
                /* Push error, but keep going*/
                HDONE_ERROR(H5E_FSPACE, H5E_CANTUNPIN, FAIL, "unable to unpin superblock")
            f->shared->sblock = NULL;
        } /* end if */
 
        /* Remove shared file struct from list of open files */
        if(H5F_sfile_remove(f->shared) < 0)
            /* Push error, but keep going*/
            HDONE_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "problems closing file")

        /* Shutdown the metadata cache */
        if(H5AC_dest(f, dxpl_id))
            /* Push error, but keep going*/
            HDONE_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "problems closing file")

        /*
         * Do not close the root group since we didn't count it, but free
         * the memory associated with it.
         */
        if(f->shared->root_grp) {
            /* Free the root group */
            if(H5G_root_free(f->shared->root_grp) < 0)
                /* Push error, but keep going*/
                HDONE_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "problems closing file")
            f->shared->root_grp = NULL;
        } /* end if */

        /* Set up I/O info for operation */
        fio_info.f = f;
        if(NULL == (fio_info.dxpl = (H5P_genplist_t *)H5I_object(dxpl_id)))
            HDONE_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "can't get property list")

        /* Destroy other components of the file */
        if(H5F__accum_reset(&fio_info, TRUE) < 0)
            /* Push error, but keep going*/
            HDONE_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "problems closing file")
        if(H5FO_dest(f) < 0)
            /* Push error, but keep going*/
            HDONE_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "problems closing file")
        f->shared->cwfs = (struct H5HG_heap_t **)H5MM_xfree(f->shared->cwfs);
        if(H5G_node_close(f) < 0)
            /* Push error, but keep going*/
            HDONE_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "problems closing file")

        /* Destroy file creation properties */
        if(H5I_GENPROP_LST != H5I_get_type(f->shared->fcpl_id))
            /* Push error, but keep going*/
            HDONE_ERROR(H5E_FILE, H5E_BADTYPE, FAIL, "not a property list")
        if(H5I_dec_ref(f->shared->fcpl_id) < 0)
            /* Push error, but keep going*/
            HDONE_ERROR(H5E_FILE, H5E_CANTDEC, FAIL, "can't close property list")

        /* Close the file */
        if(H5FD_close(f->shared->lf) < 0)
            /* Push error, but keep going*/
            HDONE_ERROR(H5E_FILE, H5E_CANTCLOSEFILE, FAIL, "unable to close file")

        /* Free mount table */
        f->shared->mtab.child = (H5F_mount_t *)H5MM_xfree(f->shared->mtab.child);
        f->shared->mtab.nalloc = 0;

        /* Destroy shared file struct */
        f->shared = (H5F_file_t *)H5FL_FREE(H5F_file_t, f->shared);

    } else if(f->shared->nrefs > 0) {
        /*
         * There are other references to the shared part of the file.
         * Only decrement the reference count.
         */
        --f->shared->nrefs;
    }

    /* Free the non-shared part of the file */
    f->open_name = (char *)H5MM_xfree(f->open_name);
    f->actual_name = (char *)H5MM_xfree(f->actual_name);
    f->extpath = (char *)H5MM_xfree(f->extpath);
    if(H5FO_top_dest(f) < 0)
        HDONE_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "problems closing file")
    f->shared = NULL;
    f = H5FL_FREE(H5F_t, f);

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_dest() */


/*-------------------------------------------------------------------------
 * Function:	H5F_open
 *
 * Purpose:	Opens (or creates) a file.  This function understands the
 *		following flags which are similar in nature to the Posix
 *		open(2) flags.
 *
 *		H5F_ACC_RDWR:	Open with read/write access. If the file is
 *				currently open for read-only access then it
 *				will be reopened. Absence of this flag
 *				implies read-only access.
 *
 *		H5F_ACC_CREAT:	Create a new file if it doesn't exist yet.
 *				The permissions are 0666 bit-wise AND with
 *				the current umask.  H5F_ACC_WRITE must also
 *				be specified.
 *
 *		H5F_ACC_EXCL:	This flag causes H5F_open() to fail if the
 *				file already exists.
 *
 *		H5F_ACC_TRUNC:	The file is truncated and a new HDF5 superblock
 *				is written.  This operation will fail if the
 *				file is already open.
 *
 *		Unlinking the file name from the group directed graph while
 *		the file is opened causes the file to continue to exist but
 *		one will not be able to upgrade the file from read-only
 *		access to read-write access by reopening it. Disk resources
 *		for the file are released when all handles to the file are
 *		closed. NOTE: This paragraph probably only applies to Unix;
 *		deleting the file name in other OS's has undefined results.
 *
 *		The CREATE_PARMS argument is optional.	A null pointer will
 *		cause the default file creation parameters to be used.
 *
 *		The ACCESS_PARMS argument is optional.  A null pointer will
 *		cause the default file access parameters to be used.
 *
 * Return:	Success:	A new file pointer.
 *		Failure:	NULL
 *
 * Programmer:	Robb Matzke
 *		Tuesday, September 23, 1997
 *
 *-------------------------------------------------------------------------
 */
H5F_t *
H5F_open(const char *name, unsigned flags, hid_t fcpl_id, hid_t fapl_id,
    hid_t dxpl_id)
{
    H5F_t              *file = NULL;        /*the success return value      */
    H5F_file_t         *shared = NULL;      /*shared part of `file'         */
    H5FD_t             *lf = NULL;          /*file driver part of `shared'  */
    unsigned            tent_flags;         /*tentative flags               */
    H5FD_class_t       *drvr;               /*file driver class info        */
    H5P_genplist_t     *a_plist;            /*file access property list     */
    H5F_close_degree_t  fc_degree;          /*file close degree             */
    H5F_t              *ret_value;          /*actual return value           */

    FUNC_ENTER_NOAPI(NULL)

    /*
     * If the driver has a `cmp' method then the driver is capable of
     * determining when two file handles refer to the same file and the
     * library can insure that when the application opens a file twice
     * that the two handles coordinate their operations appropriately.
     * Otherwise it is the application's responsibility to never open the
     * same file more than once at a time.
     */
    if(NULL == (drvr = H5FD_get_class(fapl_id)))
        HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "unable to retrieve VFL class")

    /*
     * Opening a file is a two step process. First we try to open the
     * file in a way which doesn't affect its state (like not truncating
     * or creating it) so we can compare it with files that are already
     * open. If that fails then we try again with the full set of flags
     * (only if they're different than the original failed attempt).
     * However, if the file driver can't distinquish between files then
     * there's no reason to open the file tentatively because it's the
     * application's responsibility to prevent this situation (there's no
     * way for us to detect it here anyway).
     */
    if(drvr->cmp)
	tent_flags = flags & ~(H5F_ACC_CREAT|H5F_ACC_TRUNC|H5F_ACC_EXCL);
    else
	tent_flags = flags;

    if(NULL == (lf = H5FD_open(name, tent_flags, fapl_id, HADDR_UNDEF))) {
	if(tent_flags == flags) {
#ifndef H5_USING_MEMCHECKER
            time_t mytime = HDtime(NULL);

	    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to open file: time = %s, name = '%s', tent_flags = %x", HDctime(&mytime), name, tent_flags)
#else /* H5_USING_MEMCHECKER */
	    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to open file: name = '%s', tent_flags = %x", name, tent_flags)
#endif /* H5_USING_MEMCHECKER */
        } /* end if */
        H5E_clear_stack(NULL);
	tent_flags = flags;
	if(NULL == (lf = H5FD_open(name, tent_flags, fapl_id, HADDR_UNDEF))) {
#ifndef H5_USING_MEMCHECKER
            time_t mytime = HDtime(NULL);

	    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to open file: time = %s, name = '%s', tent_flags = %x", HDctime(&mytime), name, tent_flags)
#else /* H5_USING_MEMCHECKER */
	    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to open file: name = '%s', tent_flags = %x", name, tent_flags)
#endif /* H5_USING_MEMCHECKER */
        } /* end if */
    } /* end if */

    /* Is the file already open? */
    if((shared = H5F_sfile_search(lf)) != NULL) {
	/*
	 * The file is already open, so use that one instead of the one we
	 * just opened. We only one one H5FD_t* per file so one doesn't
	 * confuse the other.  But fail if this request was to truncate the
	 * file (since we can't do that while the file is open), or if the
	 * request was to create a non-existent file (since the file already
	 * exists), or if the new request adds write access (since the
	 * readers don't expect the file to change under them).
	 */
	if(H5FD_close(lf) < 0)
	    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to close low-level file info")
	if(flags & H5F_ACC_TRUNC)
	    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to truncate a file which is already open")
	if(flags & H5F_ACC_EXCL)
	    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "file exists")
	if((flags & H5F_ACC_RDWR) && 0 == (shared->flags & H5F_ACC_RDWR))
	    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "file is already open for read-only")

        /* Allocate new "high-level" file struct */
        if((file = H5F_new(shared, flags, fcpl_id, fapl_id, NULL)) == NULL)
            HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to create new file object")
    } /* end if */
    else {
        /* Check if tentative open was good enough */
        if(flags != tent_flags) {
            /*
             * This file is not yet open by the library and the flags we used to
             * open it are different than the desired flags. Close the tentative
             * file and open it for real.
             */
            if(H5FD_close(lf) < 0) {
                file = NULL; /*to prevent destruction of wrong file*/
                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to close low-level file info")
            } /* end if */
            if(NULL == (lf = H5FD_open(name, flags, fapl_id, HADDR_UNDEF))) {
                file = NULL; /*to prevent destruction of wrong file*/
                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to open file")
            } /* end if */
        } /* end if */

        if(NULL == (file = H5F_new(NULL, flags, fcpl_id, fapl_id, lf)))
            HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to create new file object")
    } /* end else */

    /* Retain the name the file was opened with */
    file->open_name = H5MM_xstrdup(name);

    /* Short cuts */
    shared = file->shared;
    lf = shared->lf;

    /*
     * Read or write the file superblock, depending on whether the file is
     * empty or not.
     */
    if(0 == H5FD_get_eof(lf) && (flags & H5F_ACC_RDWR)) {
        /*
         * We've just opened a fresh new file (or truncated one). We need
         * to create & write the superblock.
         */

        /* Initialize information about the superblock and allocate space for it */
        /* (Writes superblock extension messages, if there are any) */
        if(H5F_super_init(file, dxpl_id) < 0)
            HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "unable to allocate file superblock")

        /* Create and open the root group */
        /* (This must be after the space for the superblock is allocated in
         *      the file, since the superblock must be at offset 0)
         */
        if(H5G_mkroot(file, dxpl_id, TRUE) < 0)
            HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "unable to create/open root group")
    } else if (1 == shared->nrefs) {
	/* Read the superblock if it hasn't been read before. */
        if(H5F_super_read(file, dxpl_id) < 0)
	    HGOTO_ERROR(H5E_FILE, H5E_READERROR, NULL, "unable to read superblock")

	/* Open the root group */
	if(H5G_mkroot(file, dxpl_id, FALSE) < 0)
	    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to read root group")
    } /* end if */

    /* Get the file access property list, for future queries */
    if(NULL == (a_plist = (H5P_genplist_t *)H5I_object(fapl_id)))
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, NULL, "not file access property list")

    /*
     * Decide the file close degree.  If it's the first time to open the
     * file, set the degree to access property list value; if it's the
     * second time or later, verify the access property list value matches
     * the degree in shared file structure.
     */
    if(H5P_get(a_plist, H5F_ACS_CLOSE_DEGREE_NAME, &fc_degree) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, NULL, "can't get file close degree")

    if(shared->nrefs == 1) {
        if(fc_degree == H5F_CLOSE_DEFAULT)
            shared->fc_degree = lf->cls->fc_degree;
        else
            shared->fc_degree = fc_degree;
    } else if(shared->nrefs > 1) {
        if(fc_degree == H5F_CLOSE_DEFAULT && shared->fc_degree != lf->cls->fc_degree)
            HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "file close degree doesn't match")
        if(fc_degree != H5F_CLOSE_DEFAULT && fc_degree != shared->fc_degree)
            HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "file close degree doesn't match")
    } /* end if */

    /* Formulate the absolute path for later search of target file for external links */
    if(H5_build_extpath(name, &file->extpath) < 0)
	HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "unable to build extpath")

    /* Formulate the actual file name, after following symlinks, etc. */
    if(H5F_build_actual_name(file, a_plist, name, &file->actual_name) < 0)
	HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, NULL, "unable to build actual name")

    /* Success */
    ret_value = file;

done:
    if(!ret_value && file)
        if(H5F_dest(file, dxpl_id, FALSE) < 0)
            HDONE_ERROR(H5E_FILE, H5E_CANTCLOSEFILE, NULL, "problems closing file")

    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_open() */


/*-------------------------------------------------------------------------
 * Function:	H5F_flush
 *
 * Purpose:	Flushes cached data.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		matzke@llnl.gov
 *		Aug 29 1997
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_flush(H5F_t *f, hid_t dxpl_id, hbool_t closing)
{
    H5F_io_info_t fio_info;             /* I/O info for operation */
    herr_t   ret_value = SUCCEED;       /* Return value */

    FUNC_ENTER_NOAPI(FAIL)

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

    /* Flush any cached dataset storage raw data */
    if(H5D_flush(f, dxpl_id) < 0)
        /* Push error, but keep going*/
        HDONE_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush dataset cache")

    /* Release any space allocated to space aggregators, so that the eoa value
     *  corresponds to the end of the space written to in the file.
     */
    /* (needs to happen before cache flush, with superblock write, since the
     *  'eoa' value is written in superblock -QAK)
     */
    if(H5MF_free_aggrs(f, dxpl_id) < 0)
        /* Push error, but keep going*/
        HDONE_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "can't release file space")

    /* Flush the entire metadata cache */
    if(H5AC_flush(f, dxpl_id) < 0)
        /* Push error, but keep going*/
        HDONE_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush metadata cache")

    /* Truncate the file to the current allocated size */
    if(H5FD_truncate(f->shared->lf, dxpl_id, closing) < 0)
        HDONE_ERROR(H5E_FILE, H5E_WRITEERROR, FAIL, "low level truncate failed")

    /* Flush the entire metadata cache again since the EOA could have changed in the truncate call. */
    if(H5AC_flush(f, dxpl_id) < 0)
        /* Push error, but keep going*/
        HDONE_ERROR(H5E_CACHE, H5E_CANTFLUSH, FAIL, "unable to flush metadata cache")

    /* Set up I/O info for operation */
    fio_info.f = f;
    if(NULL == (fio_info.dxpl = (H5P_genplist_t *)H5I_object(dxpl_id)))
        HDONE_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "can't get property list")

    /* Flush out the metadata accumulator */
    if(H5F__accum_flush(&fio_info) < 0)
        /* Push error, but keep going*/
        HDONE_ERROR(H5E_IO, H5E_CANTFLUSH, FAIL, "unable to flush metadata accumulator")

    /* Flush file buffers to disk. */
    if(H5FD_flush(f->shared->lf, dxpl_id, closing) < 0)
        /* Push error, but keep going*/
        HDONE_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "low level flush failed")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_flush() */


/*-------------------------------------------------------------------------
 * Function:	H5F_close
 *
 * Purpose:	Closes a file or causes the close operation to be pended.
 *		This function is called two ways: from the API it gets called
 *		by H5Fclose->H5I_dec_ref->H5F_close when H5I_dec_ref()
 *		decrements the file ID reference count to zero.  The file ID
 *		is removed from the H5I_FILE group by H5I_dec_ref() just
 *		before H5F_close() is called. If there are open object
 *		headers then the close is pended by moving the file to the
 *		H5I_FILE_CLOSING ID group (the f->closing contains the ID
 *		assigned to file).
 *
 *		This function is also called directly from H5O_close() when
 *		the last object header is closed for the file and the file
 *		has a pending close.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Tuesday, September 23, 1997
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_close(H5F_t *f)
{
    herr_t	        ret_value = SUCCEED;    /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    /* Sanity check */
    HDassert(f);
    HDassert(f->file_id > 0);   /* This routine should only be called when a file ID's ref count drops to zero */

    /* Perform checks for "semi" file close degree here, since closing the
     * file is not allowed if there are objects still open */
    if(f->shared->fc_degree == H5F_CLOSE_SEMI) {
        unsigned nopen_files = 0;       /* Number of open files in file/mount hierarchy */
        unsigned nopen_objs = 0;        /* Number of open objects in file/mount hierarchy */

        /* Get the number of open objects and open files on this file/mount hierarchy */
        if(H5F_mount_count_ids(f, &nopen_files, &nopen_objs) < 0)
            HGOTO_ERROR(H5E_SYM, H5E_MOUNT, FAIL, "problem checking mount hierarchy")

        /* If there are no other file IDs open on this file/mount hier., but
         * there are still open objects, issue an error and bail out now,
         * without decrementing the file ID's reference count and triggering
         * a "real" attempt at closing the file */
        if(nopen_files == 1 && nopen_objs > 0)
            HGOTO_ERROR(H5E_FILE, H5E_CANTCLOSEFILE, FAIL, "can't close file, there are objects still open")
    } /* end if */

    /* Reset the file ID for this file */
    f->file_id = -1;

    /* Attempt to close the file/mount hierarchy */
    if(H5F_try_close(f) < 0)
        HGOTO_ERROR(H5E_FILE, H5E_CANTCLOSEFILE, FAIL, "can't close file")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_close() */


/*-------------------------------------------------------------------------
 * Function:	H5F_try_close
 *
 * Purpose:	Attempts to close a file due to one of several actions:
 *                      - The reference count on the file ID dropped to zero
 *                      - The last open object was closed in the file
 *                      - The file was unmounted
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Quincey Koziol
 *		Tuesday, July 19, 2005
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_try_close(H5F_t *f)
{
    unsigned            nopen_files = 0;        /* Number of open files in file/mount hierarchy */
    unsigned            nopen_objs = 0;         /* Number of open objects in file/mount hierarchy */
    herr_t	        ret_value = SUCCEED;    /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    /* Sanity check */
    HDassert(f);
    HDassert(f->shared);

    /* Check if this file is already in the process of closing */
    if(f->closing)
        HGOTO_DONE(SUCCEED)

    /* Get the number of open objects and open files on this file/mount hierarchy */
    if(H5F_mount_count_ids(f, &nopen_files, &nopen_objs) < 0)
        HGOTO_ERROR(H5E_SYM, H5E_MOUNT, FAIL, "problem checking mount hierarchy")

    /*
     * Close file according to close degree:
     *
     *  H5F_CLOSE_WEAK:	if there are still objects open, wait until
     *			they are all closed.
     *  H5F_CLOSE_SEMI:	if there are still objects open, return fail;
     *			otherwise, close file.
     *  H5F_CLOSE_STRONG:	if there are still objects open, close them
     *			first, then close file.
     */
    switch(f->shared->fc_degree) {
        case H5F_CLOSE_WEAK:
            /*
             * If file or object IDS are still open then delay deletion of
             * resources until they have all been closed.  Flush all
             * caches and update the object header anyway so that failing to
             * close all objects isn't a major problem.
             */
            if((nopen_files + nopen_objs) > 0)
                HGOTO_DONE(SUCCEED)
            break;

        case H5F_CLOSE_SEMI:
            /* Can leave safely if file IDs are still open on this file */
            if(nopen_files > 0)
                HGOTO_DONE(SUCCEED)

            /* Sanity check: If close degree if "semi" and we have gotten this
             * far and there are objects left open, bail out now */
            HDassert(nopen_files == 0 && nopen_objs == 0);

            /* If we've gotten this far (ie. there are no open objects in the file), fall through to flush & close */
            break;

        case H5F_CLOSE_STRONG:
            /* If there are other open files in the hierarchy, we can leave now */
            if(nopen_files > 0)
                HGOTO_DONE(SUCCEED)

            /* If we've gotten this far (ie. there are no open file IDs in the file/mount hierarchy), fall through to flush & close */
            break;

        case H5F_CLOSE_DEFAULT:
        default:
            HGOTO_ERROR(H5E_FILE, H5E_CANTCLOSEFILE, FAIL, "can't close file, unknown file close degree")
    } /* end switch */

    /* Mark this file as closing (prevents re-entering file shutdown code below) */
    f->closing = TRUE;

    /* If the file close degree is "strong", close all the open objects in this file */
    if(f->shared->fc_degree == H5F_CLOSE_STRONG) {
        HDassert(nopen_files ==  0);

        /* Forced close of all opened objects in this file */
        if(f->nopen_objs > 0) {
            size_t obj_count;       /* # of open objects */
            hid_t objs[128];        /* Array of objects to close */
            herr_t result;          /* Local result from obj ID query */
            size_t u;               /* Local index variable */

            /* Get the list of IDs of open dataset, group, & attribute objects */
            while((result = H5F_get_obj_ids(f, H5F_OBJ_LOCAL | H5F_OBJ_DATASET | H5F_OBJ_GROUP | H5F_OBJ_ATTR, (int)(sizeof(objs) / sizeof(objs[0])), objs, FALSE, &obj_count)) <= 0
                    && obj_count != 0 ) {

                /* Try to close all the open objects in this file */
                for(u = 0; u < obj_count; u++)
                    if(H5I_dec_ref(objs[u]) < 0)
                        HGOTO_ERROR(H5E_ATOM, H5E_CLOSEERROR, FAIL, "can't close object")
            } /* end while */
            if(result < 0)
                HGOTO_ERROR(H5E_INTERNAL, H5E_BADITER, FAIL, "H5F_get_obj_ids failed(1)")

            /* Get the list of IDs of open named datatype objects */
            /* (Do this separately from the dataset & attribute IDs, because
             * they could be using one of the named datatypes and then the
             * open named datatype ID will get closed twice)
             */
            while((result = H5F_get_obj_ids(f, H5F_OBJ_LOCAL | H5F_OBJ_DATATYPE, (int)(sizeof(objs) / sizeof(objs[0])), objs, FALSE, &obj_count)) <= 0
                    && obj_count != 0) {

                /* Try to close all the open objects in this file */
                for(u = 0; u < obj_count; u++)
                    if(H5I_dec_ref(objs[u]) < 0)
                        HGOTO_ERROR(H5E_ATOM, H5E_CLOSEERROR, FAIL, "can't close object")
            } /* end while */
            if(result < 0)
                HGOTO_ERROR(H5E_INTERNAL, H5E_BADITER, FAIL, "H5F_get_obj_ids failed(2)")
        } /* end if */
    } /* end if */

    /* Check if this is a child file in a mounting hierarchy & proceed up the
     * hierarchy if so.
     */
    if(f->parent)
        if(H5F_try_close(f->parent) < 0)
            HGOTO_ERROR(H5E_FILE, H5E_CANTCLOSEFILE, FAIL, "can't close parent file")

    /* Unmount and close each child before closing the current file. */
    if(H5F_close_mounts(f) < 0)
        HGOTO_ERROR(H5E_FILE, H5E_CANTCLOSEFILE, FAIL, "can't unmount child files")

    /* If there is more than one reference to the shared file struct and the
     * file has an external file cache, we should see if it can be closed.  This
     * can happen if a cycle is formed with external file caches */
    if(f->shared->efc && (f->shared->nrefs > 1))
        if(H5F_efc_try_close(f) < 0)
            HGOTO_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "can't attempt to close EFC")

    /* Delay flush until the shared file struct is closed, in H5F_dest.  If the
     * application called H5Fclose, it would have been flushed in that function
     * (unless it will have been flushed in H5F_dest anyways). */

    /*
     * Destroy the H5F_t struct and decrement the reference count for the
     * shared H5F_file_t struct. If the reference count for the H5F_file_t
     * struct reaches zero then destroy it also.
     */
    if(H5F_dest(f, H5AC_dxpl_id, TRUE) < 0)
        HGOTO_ERROR(H5E_FILE, H5E_CANTCLOSEFILE, FAIL, "problems closing file")

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_try_close() */


/*-------------------------------------------------------------------------
 * Function:	H5F_get_id
 *
 * Purpose:	Get the file ID, incrementing it, or "resurrecting" it as
 *              appropriate.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Raymond Lu
 *		Oct 29, 2003
 *
 *-------------------------------------------------------------------------
 */
hid_t
H5F_get_id(H5F_t *file, hbool_t app_ref)
{
    hid_t       ret_value;

    FUNC_ENTER_NOAPI_NOINIT

    HDassert(file);

    if(file->file_id == -1) {
        /* Get an atom for the file */
        if((file->file_id = H5I_register(H5I_FILE, file, app_ref)) < 0)
	    HGOTO_ERROR(H5E_ATOM, H5E_CANTREGISTER, FAIL, "unable to atomize file")
    } else {
        /* Increment reference count on atom. */
        if(H5I_inc_ref(file->file_id, app_ref) < 0)
            HGOTO_ERROR(H5E_ATOM, H5E_CANTSET, FAIL, "incrementing file ID failed")
    } /* end else */

    ret_value = file->file_id;

done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* end H5F_get_id() */


/*-------------------------------------------------------------------------
 * Function:	H5F_incr_nopen_objs
 *
 * Purpose:	Increment the number of open objects for a file.
 *
 * Return:	Success:	The number of open objects, after the increment
 *
 * 		Failure:	(can't happen)
 *
 * Programmer:	Quincey Koziol
 *		koziol@hdfgroup.org
 *		Mar  6 2007
 *
 *-------------------------------------------------------------------------
 */
unsigned
H5F_incr_nopen_objs(H5F_t *f)
{
    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    HDassert(f);

    FUNC_LEAVE_NOAPI(++f->nopen_objs)
} /* end H5F_incr_nopen_objs() */


/*-------------------------------------------------------------------------
 * Function:	H5F_decr_nopen_objs
 *
 * Purpose:	Decrement the number of open objects for a file.
 *
 * Return:	Success:	The number of open objects, after the decrement
 *
 * 		Failure:	(can't happen)
 *
 * Programmer:	Quincey Koziol
 *		koziol@hdfgroup.org
 *		Mar  6 2007
 *
 *-------------------------------------------------------------------------
 */
unsigned
H5F_decr_nopen_objs(H5F_t *f)
{
    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    HDassert(f);

    FUNC_LEAVE_NOAPI(--f->nopen_objs)
} /* end H5F_decr_nopen_objs() */


/*-------------------------------------------------------------------------
 * Function:	H5F_build_actual_name
 *
 * Purpose:	Retrieve the name of a file, after following symlinks, etc.
 *
 * Note:	Currently only working for "POSIX I/O compatible" VFDs
 *
 * Return:	Success:        0
 *		Failure:	-1
 *
 * Programmer:	Quincey Koziol
 *		November 25, 2009
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5F_build_actual_name(const H5F_t *f, const H5P_genplist_t *fapl, const char *name,
    char **actual_name/*out*/)
{
    hid_t       new_fapl_id = -1;       /* ID for duplicated FAPL */
    herr_t      ret_value = SUCCEED;    /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    /* Sanity check */
    HDassert(f);
    HDassert(fapl);
    HDassert(name);
    HDassert(actual_name);

    /* Clear actual name pointer to begin with */
    *actual_name = NULL;

/* Assume that if the OS can't create symlinks, that we don't need to worry
 *      about resolving them either. -QAK
 */
#ifdef H5_HAVE_SYMLINK
    /* Check for POSIX I/O compatible file handle */
    if(H5F_HAS_FEATURE(f, H5FD_FEAT_POSIX_COMPAT_HANDLE)) {
        h5_stat_t lst;   /* Stat info from lstat() call */

        /* Call lstat() on the file's name */
        if(HDlstat(name, &lst) < 0)
            HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "can't retrieve stat info for file")

        /* Check for symbolic link */
        if(S_IFLNK == (lst.st_mode & S_IFMT)) {
            H5P_genplist_t *new_fapl;   /* Duplicated FAPL */
            int *fd;                    /* POSIX I/O file descriptor */
            h5_stat_t st;               /* Stat info from stat() call */
            h5_stat_t fst;              /* Stat info from fstat() call */
            char realname[PATH_MAX];    /* Fully resolved path name of file */
            hbool_t want_posix_fd;      /* Flag for retrieving file descriptor from VFD */

            /* Perform a sanity check that the file or link wasn't switched
             * between when we opened it and when we called lstat().  This is
             * according to the security best practices for lstat() documented
             * here: https://www.securecoding.cert.org/confluence/display/seccode/POS35-C.+Avoid+race+conditions+while+checking+for+the+existence+of+a+symbolic+link
             */

            /* Copy the FAPL object to modify */
            if((new_fapl_id = H5P_copy_plist(fapl, FALSE)) < 0)
                HGOTO_ERROR(H5E_FILE, H5E_CANTCOPY, FAIL, "unable to copy file access property list")
            if(NULL == (new_fapl = (H5P_genplist_t *)H5I_object(new_fapl_id)))
                HGOTO_ERROR(H5E_FILE, H5E_CANTCREATE, FAIL, "can't get property list")

            /* Set the character encoding on the new property list */
            want_posix_fd = TRUE;
            if(H5P_set(new_fapl, H5F_ACS_WANT_POSIX_FD_NAME, &want_posix_fd) < 0)
                HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set character encoding")

            /* Retrieve the file handle */
            if(H5F_get_vfd_handle(f, new_fapl_id, (void **)&fd) < 0)
                HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "can't retrieve POSIX file descriptor")

            /* Stat the filename we're resolving */
            if(HDstat(name, &st) < 0)
                HSYS_GOTO_ERROR(H5E_FILE, H5E_BADFILE, FAIL, "unable to stat file")

            /* Stat the file we opened */
            if(HDfstat(*fd, &fst) < 0)
                HSYS_GOTO_ERROR(H5E_FILE, H5E_BADFILE, FAIL, "unable to fstat file")

            /* Verify that the files are really the same */
            if(st.st_mode != fst.st_mode || st.st_ino != fst.st_ino || st.st_dev != fst.st_dev)
                HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, FAIL, "files' st_ino or st_dev fields changed!")

            /* Get the resolved path for the file name */
            if(NULL == HDrealpath(name, realname))
                HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "can't retrieve real path for file")

            /* Duplicate the resolved path for the file name */
            if(NULL == (*actual_name = (char *)H5MM_strdup(realname)))
                HGOTO_ERROR(H5E_FILE, H5E_CANTALLOC, FAIL, "can't duplicate real path")
        } /* end if */
    } /* end if */
#endif /* H5_HAVE_SYMLINK */

    /* Check if we've resolved the file's name */
    if(NULL == *actual_name) {
        /* Just duplicate the name used to open the file */
        if(NULL == (*actual_name = (char *)H5MM_strdup(name)))
            HGOTO_ERROR(H5E_FILE, H5E_CANTALLOC, FAIL, "can't duplicate open name")
    } /* end else */

done:
    /* Close the property list */
    if(new_fapl_id > 0)
        if(H5I_dec_app_ref(new_fapl_id) < 0)
            HDONE_ERROR(H5E_FILE, H5E_CANTCLOSEOBJ, FAIL, "can't close duplicated FAPL")

    FUNC_LEAVE_NOAPI(ret_value)
} /* H5F_build_actual_name() */


/*-------------------------------------------------------------------------
 * Function:	H5F_addr_encode_len
 *
 * Purpose:	Encodes an address into the buffer pointed to by *PP and
 *		then increments the pointer to the first byte after the
 *		address.  An undefined value is stored as all 1's.
 *
 * Return:	void
 *
 * Programmer:	Robb Matzke
 *		Friday, November  7, 1997
 *
 *-------------------------------------------------------------------------
 */
void
H5F_addr_encode_len(size_t addr_len, uint8_t **pp/*in,out*/, haddr_t addr)
{
    unsigned    u;              /* Local index variable */

    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    HDassert(addr_len);
    HDassert(pp && *pp);

    if(H5F_addr_defined(addr)) {
	for(u = 0; u < addr_len; u++) {
	    *(*pp)++ = (uint8_t)(addr & 0xff);
	    addr >>= 8;
	} /* end for */
	HDassert("overflow" && 0 == addr);
    } /* end if */
    else {
	for(u = 0; u < addr_len; u++)
	    *(*pp)++ = 0xff;
    } /* end else */

    FUNC_LEAVE_NOAPI_VOID
} /* end H5F_addr_encode_len() */


/*-------------------------------------------------------------------------
 * Function:	H5F_addr_encode
 *
 * Purpose:	Encodes an address into the buffer pointed to by *PP and
 *		then increments the pointer to the first byte after the
 *		address.  An undefined value is stored as all 1's.
 *
 * Return:	void
 *
 * Programmer:	Robb Matzke
 *		Friday, November  7, 1997
 *
 *-------------------------------------------------------------------------
 */
void
H5F_addr_encode(const H5F_t *f, uint8_t **pp/*in,out*/, haddr_t addr)
{
    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    HDassert(f);

    H5F_addr_encode_len(H5F_SIZEOF_ADDR(f), pp, addr);

    FUNC_LEAVE_NOAPI_VOID
} /* end H5F_addr_encode() */


/*-------------------------------------------------------------------------
 * Function:	H5F_addr_decode_len
 *
 * Purpose:	Decodes an address from the buffer pointed to by *PP and
 *		updates the pointer to point to the next byte after the
 *		address.
 *
 *		If the value read is all 1's then the address is returned
 *		with an undefined value.
 *
 * Return:	void
 *
 * Programmer:	Robb Matzke
 *		Friday, November  7, 1997
 *
 *-------------------------------------------------------------------------
 */
void
H5F_addr_decode_len(size_t addr_len, const uint8_t **pp/*in,out*/, haddr_t *addr_p/*out*/)
{
    hbool_t	    all_zero = TRUE;    /* True if address was all zeroes */
    unsigned	    u;          /* Local index variable */

    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    HDassert(addr_len);
    HDassert(pp && *pp);
    HDassert(addr_p);

    /* Reset value in destination */
    *addr_p = 0;

    /* Decode bytes from address */
    for(u = 0; u < addr_len; u++) {
        uint8_t	    c;          /* Local decoded byte */

        /* Get decoded byte (and advance pointer) */
	c = *(*pp)++;

        /* Check for non-undefined address byte value */
	if(c != 0xff)
            all_zero = FALSE;

	if(u < sizeof(*addr_p)) {
            haddr_t	    tmp = c;    /* Local copy of address, for casting */

            /* Shift decoded byte to correct position */
	    tmp <<= (u * 8);	/*use tmp to get casting right */

            /* Merge into already decoded bytes */
	    *addr_p |= tmp;
	} /* end if */
        else
            if(!all_zero)
                HDassert(0 == **pp);	/*overflow */
    } /* end for */

    /* If 'all_zero' is still TRUE, the address was entirely composed of '0xff'
     *  bytes, which is the encoded form of 'HADDR_UNDEF', so set the destination
     *  to that value */
    if(all_zero)
        *addr_p = HADDR_UNDEF;

    FUNC_LEAVE_NOAPI_VOID
} /* end H5F_addr_decode_len() */


/*-------------------------------------------------------------------------
 * Function:	H5F_addr_decode
 *
 * Purpose:	Decodes an address from the buffer pointed to by *PP and
 *		updates the pointer to point to the next byte after the
 *		address.
 *
 *		If the value read is all 1's then the address is returned
 *		with an undefined value.
 *
 * Return:	void
 *
 * Programmer:	Robb Matzke
 *		Friday, November  7, 1997
 *
 *-------------------------------------------------------------------------
 */
void
H5F_addr_decode(const H5F_t *f, const uint8_t **pp/*in,out*/, haddr_t *addr_p/*out*/)
{
    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    HDassert(f);

    H5F_addr_decode_len(H5F_SIZEOF_ADDR(f), pp, addr_p);

    FUNC_LEAVE_NOAPI_VOID
} /* end H5F_addr_decode() */


/*-------------------------------------------------------------------------
 * Function:    H5F_set_grp_btree_shared
 *
 * Purpose:     Set the grp_btree_shared field with a valid ref-count pointer.
 *
 * Return:      Success:        SUCCEED
 *              Failure:        FAIL
 *
 * Programmer:  Quincey Koziol
 *              7/19/11
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_set_grp_btree_shared(H5F_t *f, H5RC_t *rc)
{
    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Sanity check */
    HDassert(f);
    HDassert(f->shared);
    HDassert(rc);

    f->shared->grp_btree_shared = rc;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5F_set_grp_btree_shared() */


/*-------------------------------------------------------------------------
 * Function:    H5F_set_sohm_addr
 *
 * Purpose:     Set the sohm_addr field with a new value.
 *
 * Return:      Success:        SUCCEED
 *              Failure:        FAIL
 *
 * Programmer:  Quincey Koziol
 *              7/20/11
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_set_sohm_addr(H5F_t *f, haddr_t addr)
{
    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Sanity check */
    HDassert(f);
    HDassert(f->shared);

    f->shared->sohm_addr = addr;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5F_set_sohm_addr() */


/*-------------------------------------------------------------------------
 * Function:    H5F_set_sohm_vers
 *
 * Purpose:     Set the sohm_vers field with a new value.
 *
 * Return:      Success:        SUCCEED
 *              Failure:        FAIL
 *
 * Programmer:  Quincey Koziol
 *              7/20/11
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_set_sohm_vers(H5F_t *f, unsigned vers)
{
    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Sanity check */
    HDassert(f);
    HDassert(f->shared);

    f->shared->sohm_vers = vers;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5F_set_sohm_vers() */


/*-------------------------------------------------------------------------
 * Function:    H5F_set_sohm_nindexes
 *
 * Purpose:     Set the sohm_nindexes field with a new value.
 *
 * Return:      Success:        SUCCEED
 *              Failure:        FAIL
 *
 * Programmer:  Quincey Koziol
 *              7/20/11
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_set_sohm_nindexes(H5F_t *f, unsigned nindexes)
{
    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Sanity check */
    HDassert(f);
    HDassert(f->shared);

    f->shared->sohm_nindexes = nindexes;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5F_set_sohm_nindexes() */


/*-------------------------------------------------------------------------
 * Function:    H5F_set_store_msg_crt_idx
 *
 * Purpose:     Set the store_msg_crt_idx field with a new value.
 *
 * Return:      Success:        SUCCEED
 *              Failure:        FAIL
 *
 * Programmer:  Quincey Koziol
 *              7/20/11
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_set_store_msg_crt_idx(H5F_t *f, hbool_t flag)
{
    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
    FUNC_ENTER_NOAPI_NOINIT_NOERR

    /* Sanity check */
    HDassert(f);
    HDassert(f->shared);

    f->shared->store_msg_crt_idx = flag;

    FUNC_LEAVE_NOAPI(SUCCEED)
} /* H5F_set_store_msg_crt_idx() */


/*-------------------------------------------------------------------------
 * Function:    H5F_get_file_image
 *
 * Purpose:     Private version of H5Fget_file_image
 *
 * Return:      Success:        Bytes copied / number of bytes needed.
 *              Failure:        negative value
 *
 * Programmer:  John Mainzer
 *              11/15/11
 *
 *-------------------------------------------------------------------------
 */
ssize_t
H5F_get_file_image(H5F_t *file, void *buf_ptr, size_t buf_len)
{
    H5FD_t     *fd_ptr;                 /* file driver */
    haddr_t     eoa;                    /* End of file address */
    ssize_t     ret_value;              /* Return value */

    FUNC_ENTER_NOAPI_NOINIT

    /* Check args */
    if(!file || !file->shared || !file->shared->lf)
        HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, FAIL, "file_id yields invalid file pointer")
    fd_ptr = file->shared->lf;
    if(!fd_ptr->cls)
        HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, FAIL, "fd_ptr yields invalid class pointer")

    /* the address space used by the split and multi file drivers is not
     * a good fit for this call.  Since the plan is to depreciate these
     * drivers anyway, don't bother to do a "force fit".
     *
     * The following clause tests for the multi file driver, and fails
     * if the supplied file has the multi file driver as its top level
     * file driver.  However, this test will not work if there is some
     * other file driver sitting on top of the multi file driver.
     *
     * I'm not sure if this is possible at present, but in all likelyhood,
     * it will become possible in the future.  On the other hand, we may
     * remove the split/multi file drivers before then.
     *
     * I am leaving this solution in for now, but we should review it,
     * and improve the solution if necessary.
     *
     *                                          JRM -- 11/11/22
     */
    if(HDstrcmp(fd_ptr->cls->name, "multi") == 0)
        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "Not supported for multi file driver.")

    /* While the family file driver is conceptually fully compatible 
     * with the get file image operation, it sets a file driver message
     * in the super block that prevents the image being opened with any
     * driver other than the family file driver.  Needless to say, this
     * rather defeats the purpose of the get file image operation.
     *
     * While this problem is quire solvable, the required time and 
     * resources are lacking at present.  Hence, for now, we don't
     * allow the get file image operation to be perfomed on files 
     * opened with the family file driver.
     *
     * Observe that the following test only looks at the top level 
     * driver, and fails if there is some other driver sitting on to
     * of the family file driver.  
     *
     * I don't think this can happen at present, but that may change
     * in the future.
     *                                   JRM -- 12/21/11
     */
    if(HDstrcmp(fd_ptr->cls->name, "family") == 0)
        HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, FAIL, "Not supported for family file driver.")

    /* Go get the actual file size */
    if(HADDR_UNDEF == (eoa = H5FD_get_eoa(file->shared->lf, H5FD_MEM_DEFAULT)))
        HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "unable to get file size")

    /* set ret_value = to eoa -- will overwrite this if appropriate */
    ret_value = (ssize_t)eoa;

    /* test to see if a buffer was provided -- if not, we are done */
    if(buf_ptr != NULL) {
        size_t	space_needed;		/* size of file image */

        /* Check for buffer too small */
        if((haddr_t)buf_len < eoa)
            HGOTO_ERROR(H5E_FILE, H5E_BADVALUE, FAIL, "supplied buffer too small")

        space_needed = (size_t)eoa;

        /* read in the file image */
        /* (Note compensation for base address addition in internal routine) */
        if(H5FD_read(fd_ptr, H5AC_ind_dxpl_g, H5FD_MEM_DEFAULT, 0, space_needed, buf_ptr) < 0)
            HGOTO_ERROR(H5E_FILE, H5E_READERROR, FAIL, "file image read request failed")
    } /* end if */
    
done:
    FUNC_LEAVE_NOAPI(ret_value)
} /* H5F_get_file_image() */