Moved code from H5O.c to H5Oint.c

1 files changed, 2641 insertions, 0 deletions

diff --git a/src/H5Oint.c b/src/H5Oint.c
index fbaad53..6ab5393 100644
--- a/src/H5Oint.c
+++ b/src/H5Oint.c
@@ -32,7 +32,17 @@
 /***********/
 #include "H5private.h"          /* Generic Functions                        */
 #include "H5Eprivate.h"         /* Error handling                           */
+#include "H5Fprivate.h"         /* File access                              */
+#include "H5FLprivate.h"        /* Free lists                               */
+#include "H5FOprivate.h"        /* File objects                             */
+#include "H5Iprivate.h"         /* IDs                                      */
+#include "H5Lprivate.h"         /* Links                                    */
+#include "H5MFprivate.h"        /* File memory management                   */
+#ifdef H5O_ENABLE_BOGUS
+#include "H5MMprivate.h"        /* Memory management                        */
+#endif /* H5O_ENABLE_BOGUS */
 #include "H5Opkg.h"             /* Object headers                           */
+#include "H5SMprivate.h"        /* Shared object header messages            */
 
 
 /****************/
@@ -44,6 +54,17 @@
 /* Local Typedefs */
 /******************/
 
+/* User data for recursive traversal over objects from a group */
+typedef struct {
+    hid_t       obj_id;         /* The ID for the starting group */
+    H5G_loc_t	*start_loc;     /* Location of starting group */
+    hid_t       lapl_id;        /* LAPL for walking across links */
+    hid_t       dxpl_id; 	/* DXPL for operations */
+    H5SL_t     *visited;        /* Skip list for tracking visited nodes */
+    H5O_iterate_t op;           /* Application callback */
+    void       *op_data;        /* Application's op data */
+} H5O_iter_visit_ud_t;
+
 
 /********************/
 /* Package Typedefs */
@@ -54,19 +75,2639 @@
 /* Local Prototypes */
 /********************/
 
+static herr_t H5O_delete_oh(H5F_t *f, hid_t dxpl_id, H5O_t *oh);
+static herr_t H5O_obj_type_real(H5O_t *oh, H5O_type_t *obj_type);
+static herr_t H5O_get_hdr_info_real(const H5O_t *oh, H5O_hdr_info_t *hdr);
+static const H5O_obj_class_t *H5O_obj_class_real(H5O_t *oh);
+
 
 /*********************/
 /* Package Variables */
 /*********************/
 
+/* Package initialization variable */
+hbool_t H5_PKG_INIT_VAR = FALSE;
+
+/* Header message ID to class mapping
+ *
+ * Remember to increment H5O_MSG_TYPES in H5Opkg.h when adding a new
+ * message.
+ */
+const H5O_msg_class_t *const H5O_msg_class_g[] = {
+    H5O_MSG_NULL,		/*0x0000 Null				*/
+    H5O_MSG_SDSPACE,		/*0x0001 Dataspace			*/
+    H5O_MSG_LINFO,		/*0x0002 Link information		*/
+    H5O_MSG_DTYPE,		/*0x0003 Datatype			*/
+    H5O_MSG_FILL,       	/*0x0004 Old data storage -- fill value */
+    H5O_MSG_FILL_NEW,		/*0x0005 New data storage -- fill value */
+    H5O_MSG_LINK,		/*0x0006 Link 				*/
+    H5O_MSG_EFL,		/*0x0007 Data storage -- external data files */
+    H5O_MSG_LAYOUT,		/*0x0008 Data Layout			*/
+#ifdef H5O_ENABLE_BOGUS
+    H5O_MSG_BOGUS_VALID,	/*0x0009 "Bogus valid" (for testing)	*/
+#else /* H5O_ENABLE_BOGUS */
+    NULL,			/*0x0009 "Bogus valid" (for testing)	*/
+#endif /* H5O_ENABLE_BOGUS */
+    H5O_MSG_GINFO,		/*0x000A Group information		*/
+    H5O_MSG_PLINE,		/*0x000B Data storage -- filter pipeline */
+    H5O_MSG_ATTR,		/*0x000C Attribute			*/
+    H5O_MSG_NAME,		/*0x000D Object name			*/
+    H5O_MSG_MTIME,		/*0x000E Object modification date and time */
+    H5O_MSG_SHMESG,		/*0x000F File-wide shared message table */
+    H5O_MSG_CONT,		/*0x0010 Object header continuation	*/
+    H5O_MSG_STAB,		/*0x0011 Symbol table			*/
+    H5O_MSG_MTIME_NEW,		/*0x0012 New Object modification date and time */
+    H5O_MSG_BTREEK,		/*0x0013 Non-default v1 B-tree 'K' values */
+    H5O_MSG_DRVINFO,		/*0x0014 Driver info settings		*/
+    H5O_MSG_AINFO,		/*0x0015 Attribute information		*/
+    H5O_MSG_REFCOUNT,		/*0x0016 Object's ref. count		*/
+    H5O_MSG_FSINFO,		/*0x0017 Free-space manager info        */
+    H5O_MSG_MDCI,               /*0x0018 Metadata cache image           */
+    H5O_MSG_UNKNOWN,		/*0x0019 Placeholder for unknown message */
+#ifdef H5O_ENABLE_BOGUS
+    H5O_MSG_BOGUS_INVALID, 	/*0x001A "Bogus invalid" (for testing) 	*/
+#else /* H5O_ENABLE_BOGUS */
+    NULL,                       /*0x001A "Bogus invalid" (for testing) 	*/
+#endif /* H5O_ENABLE_BOGUS */
+};
+
+/* Declare a free list to manage the H5O_t struct */
+H5FL_DEFINE(H5O_t);
+
+/* Declare a free list to manage the H5O_mesg_t sequence information */
+H5FL_SEQ_DEFINE(H5O_mesg_t);
+
+/* Declare a free list to manage the H5O_chunk_t sequence information */
+H5FL_SEQ_DEFINE(H5O_chunk_t);
+
+/* Declare a free list to manage the chunk image information */
+H5FL_BLK_DEFINE(chunk_image);
+
+/* Declare external the free list for H5O_cont_t sequences */
+H5FL_SEQ_EXTERN(H5O_cont_t);
+
 
 /*****************************/
 /* Library Private Variables */
 /*****************************/
 
+/* Declare external the free list for time_t's */
+H5FL_EXTERN(time_t);
+
+/* Declare external the free list for H5_obj_t's */
+H5FL_EXTERN(H5_obj_t);
+
 
 /*******************/
 /* Local Variables */
 /*******************/
 
+/* Header object ID to class mapping */
+/*
+ * Initialize the object class info table.  Begin with the most general types
+ * and end with the most specific. For instance, any object that has a
+ * datatype message is a datatype but only some of them are datasets.
+ */
+static const H5O_obj_class_t *const H5O_obj_class_g[] = {
+    H5O_OBJ_DATATYPE,		/* Datatype object (H5O_TYPE_NAMED_DATATYPE - 2) */
+    H5O_OBJ_DATASET,		/* Dataset object (H5O_TYPE_DATASET - 1) */
+    H5O_OBJ_GROUP,		/* Group object (H5O_TYPE_GROUP - 0) */
+};
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O__init_package
+ *
+ * Purpose:	Initialize information specific to H5O interface.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Thursday, January 18, 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O__init_package(void)
+{
+    FUNC_ENTER_PACKAGE_NOERR
+
+    /* H5O interface sanity checks */
+    HDcompile_assert(H5O_MSG_TYPES == NELMTS(H5O_msg_class_g));
+    HDcompile_assert(sizeof(H5O_fheap_id_t) == H5O_FHEAP_ID_LEN);
+
+    HDcompile_assert(H5O_UNKNOWN_ID < H5O_MSG_TYPES);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5O__init_package() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_create
+ *
+ * Purpose:	Creates a new object header. Allocates space for it and
+ *              then calls an initialization function. The object header
+ *              is opened for write access and should eventually be
+ *              closed by calling H5O_close().
+ *
+ * Return:	Success:	Non-negative, the ENT argument contains
+ *				information about the object header,
+ *				including its address.
+ *
+ *		Failure:	Negative
+ *
+ * Programmer:	Robb Matzke
+ *		matzke@llnl.gov
+ *		Aug  5 1997
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_create(H5F_t *f, hid_t dxpl_id, size_t size_hint, size_t initial_rc,
+    hid_t ocpl_id, H5O_loc_t *loc/*out*/)
+{
+    H5P_genplist_t  *oc_plist;          /* Object creation property list */
+    H5O_t      *oh = NULL;              /* Object header created */
+    haddr_t     oh_addr;                /* Address of initial object header */
+    size_t      oh_size;                /* Size of initial object header */
+    uint8_t	oh_flags;		/* Object header's initial status flags */
+    unsigned    insert_flags = H5AC__NO_FLAGS_SET; /* Flags for inserting object header into cache */
+    hbool_t     store_msg_crt_idx;      /* Whether to always store message creation indices for this file */
+    herr_t      ret_value = SUCCEED;    /* return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* check args */
+    HDassert(f);
+    HDassert(loc);
+    HDassert(TRUE == H5P_isa_class(ocpl_id, H5P_OBJECT_CREATE));
+
+    /* Check for invalid access request */
+    if(0 == (H5F_INTENT(f) & H5F_ACC_RDWR))
+        HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, FAIL, "no write intent on file")
+
+    /* Make certain we allocate at least a reasonable size for the object header */
+    size_hint = H5O_ALIGN_F(f, MAX(H5O_MIN_SIZE, size_hint));
+
+    /* Get the property list */
+    if(NULL == (oc_plist = (H5P_genplist_t *)H5I_object(ocpl_id)))
+        HGOTO_ERROR(H5E_PLIST, H5E_BADTYPE, FAIL, "not a property list")
+
+    /* Get any object header status flags set by properties */
+    if(H5P_get(oc_plist, H5O_CRT_OHDR_FLAGS_NAME, &oh_flags) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get object header flags")
+
+    /* Allocate the object header and zero out header fields */
+    if(NULL == (oh = H5FL_CALLOC(H5O_t)))
+        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
+
+    /* Initialize file-specific information for object header */
+    store_msg_crt_idx = H5F_STORE_MSG_CRT_IDX(f);
+    if(H5F_USE_LATEST_FLAGS(f, H5F_LATEST_OBJ_HEADER) || store_msg_crt_idx || (oh_flags & H5O_HDR_ATTR_CRT_ORDER_TRACKED))
+        oh->version = H5O_VERSION_LATEST;
+    else
+        oh->version = H5O_VERSION_1;
+    oh->sizeof_size = H5F_SIZEOF_SIZE(f);
+    oh->sizeof_addr = H5F_SIZEOF_ADDR(f);
+    oh->swmr_write = !!(H5F_INTENT(f) & H5F_ACC_SWMR_WRITE);
+#ifdef H5O_ENABLE_BAD_MESG_COUNT
+    /* Check whether the "bad message count" property is set */
+    if(H5P_exist_plist(oc_plist, H5O_BAD_MESG_COUNT_NAME) > 0) {
+        /* Retrieve bad message count flag */
+        if(H5P_get(oc_plist, H5O_BAD_MESG_COUNT_NAME, &oh->store_bad_mesg_count) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't get bad message count flag")
+    }
+#endif /* H5O_ENABLE_BAD_MESG_COUNT */
+
+    /* Create object header proxy if doing SWMR writes */
+    if(oh->swmr_write) {
+        /* Create virtual entry, for use as proxy */
+        if(NULL == (oh->proxy = H5AC_proxy_entry_create()))
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTCREATE, FAIL, "can't create object header proxy")
+    }
+    else
+        oh->proxy = NULL;
+
+    /* Set initial status flags */
+    oh->flags = oh_flags;
+
+    /* Initialize version-specific fields */
+    if(oh->version > H5O_VERSION_1) {
+        /* Initialize all time fields with current time, if we are storing them */
+        if(oh->flags & H5O_HDR_STORE_TIMES)
+            oh->atime = oh->mtime = oh->ctime = oh->btime = H5_now();
+        else
+            oh->atime = oh->mtime = oh->ctime = oh->btime = 0;
+
+        /* Make certain attribute creation order tracking is enabled if
+         *      attributes can be shared in this file.
+         */
+        if(store_msg_crt_idx)
+            oh->flags |= H5O_HDR_ATTR_CRT_ORDER_TRACKED;
+
+        /* Retrieve attribute storage phase change values from property list */
+        if(H5P_get(oc_plist, H5O_CRT_ATTR_MAX_COMPACT_NAME, &oh->max_compact) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get max. # of compact attributes")
+        if(H5P_get(oc_plist, H5O_CRT_ATTR_MIN_DENSE_NAME, &oh->min_dense) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't get min. # of dense attributes")
+
+        /* Check for non-default attribute storage phase change values */
+        if(oh->max_compact != H5O_CRT_ATTR_MAX_COMPACT_DEF || oh->min_dense != H5O_CRT_ATTR_MIN_DENSE_DEF)
+            oh->flags |= H5O_HDR_ATTR_STORE_PHASE_CHANGE;
+
+        /* Determine correct value for chunk #0 size bits */
+/* Avoid compiler warning on 32-bit machines */
+#if H5_SIZEOF_SIZE_T > H5_SIZEOF_INT32_T
+        if(size_hint > 4294967295UL)
+            oh->flags |= H5O_HDR_CHUNK0_8;
+        else
+#endif /* H5_SIZEOF_SIZE_T > H5_SIZEOF_INT32_T */
+        if(size_hint > 65535)
+            oh->flags |= H5O_HDR_CHUNK0_4;
+        else if(size_hint > 255)
+            oh->flags |= H5O_HDR_CHUNK0_2;
+    } /* end if */
+    else {
+        /* Reset unused time fields */
+        oh->atime = oh->mtime = oh->ctime = oh->btime = 0;
+    } /* end else */
+
+    /* Compute total size of initial object header */
+    /* (i.e. object header prefix and first chunk) */
+    oh_size = (size_t)H5O_SIZEOF_HDR(oh) + size_hint;
+
+    /* Allocate disk space for header and first chunk */
+    if(HADDR_UNDEF == (oh_addr = H5MF_alloc(f, H5FD_MEM_OHDR, dxpl_id, (hsize_t)oh_size)))
+        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "file allocation failed for object header")
+
+    /* Create the chunk list */
+    oh->nchunks = oh->alloc_nchunks = 1;
+    if(NULL == (oh->chunk = H5FL_SEQ_MALLOC(H5O_chunk_t, (size_t)oh->alloc_nchunks)))
+        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
+
+    /* Initialize the first chunk */
+    oh->chunk[0].addr = oh_addr;
+    oh->chunk[0].size = oh_size;
+    oh->chunk[0].gap = 0;
+
+    /* Allocate enough space for the first chunk */
+    /* (including space for serializing the object header prefix */
+    if(NULL == (oh->chunk[0].image = H5FL_BLK_CALLOC(chunk_image, oh_size)))
+        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
+    oh->chunk[0].chunk_proxy = NULL;
+
+    /* Put magic # for object header in first chunk */
+    if(oh->version > H5O_VERSION_1)
+        HDmemcpy(oh->chunk[0].image, H5O_HDR_MAGIC, (size_t)H5_SIZEOF_MAGIC);
+
+    /* Create the message list */
+    oh->nmesgs = 1;
+    oh->alloc_nmesgs = H5O_NMESGS;
+    if(NULL == (oh->mesg = H5FL_SEQ_CALLOC(H5O_mesg_t, oh->alloc_nmesgs)))
+        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
+
+    /* Initialize the initial "null" message, covering the entire first chunk */
+    oh->mesg[0].type = H5O_MSG_NULL;
+    oh->mesg[0].dirty = TRUE;
+    oh->mesg[0].native = NULL;
+    oh->mesg[0].raw = oh->chunk[0].image + (H5O_SIZEOF_HDR(oh) - H5O_SIZEOF_CHKSUM_OH(oh)) + H5O_SIZEOF_MSGHDR_OH(oh);
+    oh->mesg[0].raw_size = size_hint - (size_t)H5O_SIZEOF_MSGHDR_OH(oh);
+    oh->mesg[0].chunkno = 0;
+
+    /* Check for non-zero initial refcount on the object header */
+    if(initial_rc > 0) {
+        /* Set the initial refcount & pin the header when its inserted */
+        oh->rc = initial_rc;
+        insert_flags |= H5AC__PIN_ENTRY_FLAG;
+    }
+
+    /* Set metadata tag in dxpl_id */
+    H5_BEGIN_TAG(dxpl_id, oh_addr, FAIL);
+
+    /* Cache object header */
+    if(H5AC_insert_entry(f, dxpl_id, H5AC_OHDR, oh_addr, oh, insert_flags) < 0)
+        HGOTO_ERROR_TAG(H5E_OHDR, H5E_CANTINSERT, FAIL, "unable to cache object header")
+
+    /* Reset object header pointer, now that it's been inserted into the cache */
+    oh = NULL;
+
+    /* Reset metadata tag in dxpl_id */
+    H5_END_TAG(FAIL);
+
+    /* Set up object location */
+    loc->file = f;
+    loc->addr = oh_addr;
+
+    /* Open it */
+    if(H5O_open(loc) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTOPENOBJ, FAIL, "unable to open object header")
+
+done:
+    if(ret_value < 0 && oh)
+        if(H5O__free(oh) < 0)
+            HDONE_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "unable to destroy object header data")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_create() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_open
+ *
+ * Purpose:	Opens an object header which is described by the symbol table
+ *		entry OBJ_ENT.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Robb Matzke
+ *		Monday, January	 5, 1998
+ *
+ * Modification:
+ *              Raymond Lu
+ *              5 November 2007
+ *              Turn off the holding file variable if it's on.  When it's
+ *              needed, the caller will turn it on again.
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_open(H5O_loc_t *loc)
+{
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* Check args */
+    HDassert(loc);
+    HDassert(loc->file);
+
+#ifdef H5O_DEBUG
+    if(H5DEBUG(O))
+        HDfprintf(H5DEBUG(O), "> %a\n", loc->addr);
+#endif
+
+    /* Turn off the variable for holding file or increment open-lock counters */
+    if(loc->holding_file)
+     	loc->holding_file = FALSE;
+    else
+        H5F_INCR_NOPEN_OBJS(loc->file);
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_open() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_open_name
+ *
+ * Purpose:	Opens an object within an HDF5 file.
+ *
+ * Return:	Success:	An open object identifier
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *		March  5 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+hid_t
+H5O_open_name(H5G_loc_t *loc, const char *name, hid_t lapl_id, hid_t dxpl_id, hbool_t app_ref)
+{
+    H5G_loc_t   obj_loc;                /* Location used to open group */
+    H5G_name_t  obj_path;            	/* Opened object group hier. path */
+    H5O_loc_t   obj_oloc;            	/* Opened object object location */
+    hbool_t     loc_found = FALSE;      /* Entry at 'name' found */
+    hid_t       ret_value = FAIL;
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* Check args */
+    HDassert(loc);
+    HDassert(name && *name);
+
+    /* Set up opened group location to fill in */
+    obj_loc.oloc = &obj_oloc;
+    obj_loc.path = &obj_path;
+    H5G_loc_reset(&obj_loc);
+
+    /* Find the object's location */
+    if(H5G_loc_find(loc, name, &obj_loc/*out*/, lapl_id, dxpl_id) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_NOTFOUND, FAIL, "object not found")
+    loc_found = TRUE;
+
+    /* Open the object */
+    if((ret_value = H5O_open_by_loc(&obj_loc, lapl_id, dxpl_id, app_ref)) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTOPENOBJ, FAIL, "unable to open object")
+
+done:
+    if(ret_value < 0 && loc_found)
+        if(H5G_loc_free(&obj_loc) < 0)
+            HDONE_ERROR(H5E_OHDR, H5E_CANTRELEASE, FAIL, "can't free location")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_open_name() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_open_by_loc
+ *
+ * Purpose:	Opens an object and returns an ID given its group loction.
+ *
+ * Return:	Success:	Open object identifier
+ *		Failure:	Negative
+ *
+ * Programmer:	James Laird
+ *		July 25 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+hid_t
+H5O_open_by_loc(const H5G_loc_t *obj_loc, hid_t lapl_id, hid_t dxpl_id, hbool_t app_ref)
+{
+    const H5O_obj_class_t *obj_class;   /* Class of object for location */
+    hid_t               ret_value = H5I_INVALID_HID;    /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    HDassert(obj_loc);
+
+    /* Get the object class for this location */
+    if(NULL == (obj_class = H5O_obj_class(obj_loc->oloc, dxpl_id)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "unable to determine object class")
+
+    /* Call the object class's 'open' routine */
+    HDassert(obj_class->open);
+    if((ret_value = obj_class->open(obj_loc, lapl_id, dxpl_id, app_ref)) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTOPENOBJ, FAIL, "unable to open object")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_open_by_loc() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_close
+ *
+ * Purpose:	Closes an object header that was previously open.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Robb Matzke
+ *		Monday, January	 5, 1998
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_close(H5O_loc_t *loc, hbool_t *file_closed /*out*/)
+{
+    herr_t ret_value = SUCCEED;   /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* Check args */
+    HDassert(loc);
+    HDassert(loc->file);
+    HDassert(H5F_NOPEN_OBJS(loc->file) > 0);
+
+    /* Set the file_closed flag to the default value.
+     * This flag lets downstream code know if the file struct is
+     * still accessible and/or likely to contain useful data.
+     * It's needed by the evict-on-close code. Clients can ignore
+     * this value by passing in NULL.
+     */
+    if(file_closed)
+        *file_closed = FALSE;
+
+    /* Decrement open-lock counters */
+    H5F_DECR_NOPEN_OBJS(loc->file);
+
+#ifdef H5O_DEBUG
+    if(H5DEBUG(O)) {
+        if(H5F_FILE_ID(loc->file)< 0 && 1 == H5F_NREFS(loc->file))
+            HDfprintf(H5DEBUG(O), "< %a auto %lu remaining\n",
+                loc->addr, (unsigned long)H5F_NOPEN_OBJS(loc->file));
+	else
+	    HDfprintf(H5DEBUG(O), "< %a\n", loc->addr);
+    }
+#endif
+
+    /*
+     * If the file open object count has reached the number of open mount points
+     * (each of which has a group open in the file) attempt to close the file.
+     */
+    if(H5F_NOPEN_OBJS(loc->file) == H5F_NMOUNTS(loc->file))
+        /* Attempt to close down the file hierarchy */
+        if(H5F_try_close(loc->file, file_closed) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTCLOSEFILE, FAIL, "problem attempting file close")
+
+    /* Release location information */
+    if(H5O_loc_free(loc) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTRELEASE, FAIL, "problem attempting to free location")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_close() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_link_oh
+ *
+ * Purpose:	Adjust the link count for an open object header by adding
+ *		ADJUST to the link count.
+ *
+ * Return:	Success:	New link count
+ *
+ *		Failure:	Negative
+ *
+ * Programmer:	Robb Matzke
+ *		matzke@llnl.gov
+ *		Aug  5 1997
+ *
+ *-------------------------------------------------------------------------
+ */
+int
+H5O_link_oh(H5F_t *f, int adjust, hid_t dxpl_id, H5O_t *oh, hbool_t *deleted)
+{
+    haddr_t addr = H5O_OH_GET_ADDR(oh);     /* Object header address */
+    int	ret_value = -1;                     /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* check args */
+    HDassert(f);
+    HDassert(oh);
+    HDassert(deleted);
+
+    /* Check for adjusting link count */
+    if(adjust) {
+        if(adjust < 0) {
+            /* Check for too large of an adjustment */
+            if((unsigned)(-adjust) > oh->nlink)
+                HGOTO_ERROR(H5E_OHDR, H5E_LINKCOUNT, FAIL, "link count would be negative")
+
+            /* Adjust the link count for the object header */
+            oh->nlink = (unsigned)((int)oh->nlink + adjust);
+
+            /* Mark object header as dirty in cache */
+            if(H5AC_mark_entry_dirty(oh) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTMARKDIRTY, FAIL, "unable to mark object header as dirty")
+
+            /* Check if the object should be deleted */
+            if(oh->nlink == 0) {
+                /* Check if the object is still open by the user */
+                if(H5FO_opened(f, addr) != NULL) {
+                    /* Flag the object to be deleted when it's closed */
+                    if(H5FO_mark(f, addr, TRUE) < 0)
+                        HGOTO_ERROR(H5E_OHDR, H5E_CANTDELETE, FAIL, "can't mark object for deletion")
+                } /* end if */
+                else {
+                    /* Mark the object header for deletion */
+                    *deleted = TRUE;
+                } /* end else */
+            } /* end if */
+        } /* end if */
+        else {
+            /* A new object, or one that will be deleted */
+            if(0 == oh->nlink) {
+                /* Check if the object is currently open, but marked for deletion */
+                if(H5FO_marked(f, addr)) {
+                    /* Remove "delete me" flag on the object */
+                    if(H5FO_mark(f, addr, FALSE) < 0)
+                        HGOTO_ERROR(H5E_OHDR, H5E_CANTDELETE, FAIL, "can't mark object for deletion")
+                } /* end if */
+            } /* end if */
+
+            /* Adjust the link count for the object header */
+            oh->nlink = (unsigned)((int)oh->nlink + adjust);
+
+            /* Mark object header as dirty in cache */
+            if(H5AC_mark_entry_dirty(oh) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTMARKDIRTY, FAIL, "unable to mark object header as dirty")
+        } /* end if */
+
+        /* Check for operations on refcount message */
+        if(oh->version > H5O_VERSION_1) {
+            /* Check if the object has a refcount message already */
+            if(oh->has_refcount_msg) {
+                /* Check for removing refcount message */
+                if(oh->nlink <= 1) {
+                    if(H5O_msg_remove_real(f, oh, H5O_MSG_REFCOUNT, H5O_ALL, NULL, NULL, TRUE, dxpl_id) < 0)
+                        HGOTO_ERROR(H5E_OHDR, H5E_CANTDELETE, FAIL, "unable to delete refcount message")
+                    oh->has_refcount_msg = FALSE;
+                } /* end if */
+                /* Update refcount message with new link count */
+                else {
+                    H5O_refcount_t refcount = oh->nlink;
+
+                    if(H5O_msg_write_real(f, dxpl_id, oh, H5O_MSG_REFCOUNT, H5O_MSG_FLAG_DONTSHARE, 0, &refcount) < 0)
+                        HGOTO_ERROR(H5E_OHDR, H5E_CANTUPDATE, FAIL, "unable to update refcount message")
+                } /* end else */
+            } /* end if */
+            else {
+                /* Check for adding refcount message to object */
+                if(oh->nlink > 1) {
+                    H5O_refcount_t refcount = oh->nlink;
+
+                    if(H5O_msg_append_real(f, dxpl_id, oh, H5O_MSG_REFCOUNT, H5O_MSG_FLAG_DONTSHARE, 0, &refcount) < 0)
+                        HGOTO_ERROR(H5E_OHDR, H5E_CANTINSERT, FAIL, "unable to create new refcount message")
+                    oh->has_refcount_msg = TRUE;
+                } /* end if */
+            } /* end else */
+        } /* end if */
+    } /* end if */
+
+    /* Set return value */
+    ret_value = (int)oh->nlink;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_link_oh() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_link
+ *
+ * Purpose:	Adjust the link count for an object header by adding
+ *		ADJUST to the link count.
+ *
+ * Return:	Success:	New link count
+ *
+ *		Failure:	Negative
+ *
+ * Programmer:	Robb Matzke
+ *		matzke@llnl.gov
+ *		Aug  5 1997
+ *
+ *-------------------------------------------------------------------------
+ */
+int
+H5O_link(const H5O_loc_t *loc, int adjust, hid_t dxpl_id)
+{
+    H5O_t	*oh = NULL;
+    hbool_t deleted = FALSE;            /* Whether the object was deleted */
+    int	ret_value = -1;                 /* Return value */
+
+    FUNC_ENTER_NOAPI_TAG(dxpl_id, loc->addr, FAIL)
+
+    /* check args */
+    HDassert(loc);
+    HDassert(loc->file);
+    HDassert(H5F_addr_defined(loc->addr));
+
+    /* Pin the object header */
+    if(NULL == (oh = H5O_pin(loc, dxpl_id)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTPIN, FAIL, "unable to pin object header")
+
+    /* Call the "real" link routine */
+    if((ret_value = H5O_link_oh(loc->file, adjust, dxpl_id, oh, &deleted)) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_LINKCOUNT, FAIL, "unable to adjust object link count")
+
+done:
+    if(oh && H5O_unpin(oh) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTUNPIN, FAIL, "unable to unpin object header")
+    if(ret_value >= 0 && deleted && H5O_delete(loc->file, dxpl_id, loc->addr) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTDELETE, FAIL, "can't delete object from file")
+
+    FUNC_LEAVE_NOAPI_TAG(ret_value, FAIL)
+} /* end H5O_link() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_protect
+ *
+ * Purpose:	Wrapper around H5AC_protect for use during a H5O_protect->
+ *              H5O_msg_append->...->H5O_msg_append->H5O_unprotect sequence of calls
+ *              during an object's creation.
+ *
+ * Return:	Success:	Pointer to the object header structure for the
+ *                              object.
+ *		Failure:	NULL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Dec 31 2002
+ *
+ *-------------------------------------------------------------------------
+ */
+H5O_t *
+H5O_protect(const H5O_loc_t *loc, hid_t dxpl_id, unsigned prot_flags,
+    hbool_t pin_all_chunks)
+{
+    H5O_t *oh = NULL;           /* Object header protected */
+    H5O_cache_ud_t udata;       /* User data for protecting object header */
+    H5O_cont_msgs_t cont_msg_info;      /* Continuation message info */
+    unsigned file_intent;       /* R/W intent on file */
+    H5O_t *ret_value = NULL;    /* Return value */
+
+    FUNC_ENTER_NOAPI_TAG(dxpl_id, loc->addr, NULL)
+
+    /* check args */
+    HDassert(loc);
+    HDassert(loc->file);
+
+    /* prot_flags may only contain the H5AC__READ_ONLY_FLAG */
+    HDassert((prot_flags & (unsigned)(~H5AC__READ_ONLY_FLAG)) == 0);
+
+    /* Check for valid address */
+    if(!H5F_addr_defined(loc->addr))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, NULL, "address undefined")
+
+    /* Check for write access on the file */
+    file_intent = H5F_INTENT(loc->file);
+    if((0 == (prot_flags & H5AC__READ_ONLY_FLAG)) && (0 == (file_intent & H5F_ACC_RDWR)))
+        HGOTO_ERROR(H5E_OHDR, H5E_BADVALUE, NULL, "no write intent on file")
+
+    /* Construct the user data for protect callback */
+    udata.made_attempt = FALSE;
+    udata.v1_pfx_nmesgs = 0;
+    udata.chunk0_size = 0;
+    udata.oh = NULL;
+    udata.common.f = loc->file;
+    udata.common.dxpl_id = dxpl_id;
+    udata.common.file_intent = file_intent;
+    udata.common.merged_null_msgs = 0;
+    HDmemset(&cont_msg_info, 0, sizeof(cont_msg_info));
+    udata.common.cont_msg_info = &cont_msg_info;
+    udata.common.addr = loc->addr;
+
+    /* Lock the object header into the cache */
+    if(NULL == (oh = (H5O_t *)H5AC_protect(loc->file, dxpl_id, H5AC_OHDR, loc->addr, &udata, prot_flags)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, NULL, "unable to load object header")
+
+    /* Check if there are any continuation messages to process */
+    if(cont_msg_info.nmsgs > 0) {
+        size_t curr_msg;        /* Current continuation message to process */
+        H5O_chk_cache_ud_t chk_udata;   /* User data for loading chunk */
+
+        /* Sanity check - we should only have continuation messages to process
+         *      when the object header is actually loaded from the file.
+         */
+        HDassert(udata.made_attempt == TRUE);
+        HDassert(cont_msg_info.msgs);
+
+        /* Construct the user data for protecting chunks */
+        chk_udata.decoding = TRUE;
+        chk_udata.oh = oh;
+        chk_udata.chunkno = UINT_MAX;   /* Set to invalid value, for better error detection */
+        chk_udata.common.f = loc->file;
+        chk_udata.common.dxpl_id = dxpl_id;
+        chk_udata.common.file_intent = file_intent;
+        chk_udata.common.merged_null_msgs = udata.common.merged_null_msgs;
+        chk_udata.common.cont_msg_info = &cont_msg_info;
+
+        /* Read in continuation messages, until there are no more */
+        /* (Note that loading chunks could increase the # of continuation
+         *      messages if new ones are found - QAK, 19/11/2016)
+         */
+        curr_msg = 0;
+        while(curr_msg < cont_msg_info.nmsgs) {
+            H5O_chunk_proxy_t *chk_proxy;       /* Proxy for chunk, to bring it into memory */
+#ifndef NDEBUG
+            size_t chkcnt = oh->nchunks;      /* Count of chunks (for sanity checking) */
+#endif /* NDEBUG */
+
+            /* Bring the chunk into the cache */
+            /* (which adds to the object header) */
+            chk_udata.common.addr = cont_msg_info.msgs[curr_msg].addr;
+            chk_udata.size = cont_msg_info.msgs[curr_msg].size;
+            if(NULL == (chk_proxy = (H5O_chunk_proxy_t *)H5AC_protect(loc->file, dxpl_id, H5AC_OHDR_CHK, cont_msg_info.msgs[curr_msg].addr, &chk_udata, prot_flags)))
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, NULL, "unable to load object header chunk")
+
+            /* Sanity check */
+            HDassert(chk_proxy->oh == oh);
+            HDassert(chk_proxy->chunkno == chkcnt);
+            HDassert(oh->nchunks == (chkcnt + 1));
+
+            /* Release the chunk from the cache */
+            if(H5AC_unprotect(loc->file, dxpl_id, H5AC_OHDR_CHK, cont_msg_info.msgs[curr_msg].addr, chk_proxy, H5AC__NO_FLAGS_SET) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, NULL, "unable to release object header chunk")
+
+            /* Advance to next continuation message */
+            curr_msg++;
+        } /* end while */
+
+        /* Release any continuation messages built up */
+        cont_msg_info.msgs = (H5O_cont_t *)H5FL_SEQ_FREE(H5O_cont_t, cont_msg_info.msgs);
+
+        /* Pass back out some of the chunk's user data */
+        udata.common.merged_null_msgs = chk_udata.common.merged_null_msgs;
+    } /* end if */
+
+    /* Check for incorrect # of object header messages, if we've just loaded
+     *  this object header from the file
+     */
+    if(udata.made_attempt) {
+/* Don't enforce the error on an incorrect # of object header messages bug
+ *      unless strict format checking is enabled.  This allows for older
+ *      files, created with a version of the library that had a bug in tracking
+ *      the correct # of header messages to be read in without the library
+ *      erroring out here. -QAK
+ */
+#ifdef H5_STRICT_FORMAT_CHECKS
+        /* Check for incorrect # of messages in v1 object header */
+        if(oh->version == H5O_VERSION_1 &&
+                (oh->nmesgs + udata.common.merged_null_msgs) != udata.v1_pfx_nmesgs)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, NULL, "corrupt object header - incorrect # of messages")
+#endif /* H5_STRICT_FORMAT_CHECKS */
+    } /* end if */
+
+#ifdef H5O_DEBUG
+H5O_assert(oh);
+#endif /* H5O_DEBUG */
+
+    /* Pin the other chunks also when requested, so that the object header
+     *  proxy can be set up.
+     */
+    if(pin_all_chunks && oh->nchunks > 1) {
+        unsigned u;         /* Local index variable */
+
+        /* Sanity check */
+        HDassert(oh->swmr_write);
+
+        /* Iterate over chunks > 0 */
+        for(u = 1; u < oh->nchunks; u++) {
+            H5O_chunk_proxy_t *chk_proxy;       /* Chunk proxy */
+
+            /* Protect chunk */
+            if(NULL == (chk_proxy = H5O_chunk_protect(loc->file, dxpl_id, oh, u)))
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, NULL, "unable to protect object header chunk")
+
+            /* Pin chunk proxy*/
+            if(H5AC_pin_protected_entry(chk_proxy) < 0 )
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTPIN, NULL, "unable to pin object header chunk")
+
+            /* Unprotect chunk */
+            if(H5O_chunk_unprotect(loc->file, dxpl_id, chk_proxy, FALSE) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, NULL, "unable to unprotect object header chunk")
+
+            /* Preserve chunk proxy pointer for later */
+            oh->chunk[u].chunk_proxy = chk_proxy;
+        } /* end for */
+
+        /* Set the flag for the unprotect */
+        oh->chunks_pinned = TRUE;
+    } /* end if */
+
+    /* Set return value */
+    ret_value = oh;
+
+done:
+    if(ret_value == NULL && oh)
+        if(H5O_unprotect(loc, dxpl_id, oh, H5AC__NO_FLAGS_SET) < 0)
+            HDONE_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, NULL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI_TAG(ret_value, NULL)
+} /* end H5O_protect() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_pin
+ *
+ * Purpose:	Pin an object header down for use during a sequence of message
+ *              operations, which prevents the object header from being
+ *              evicted from the cache.
+ *
+ * Return:	Success:	Pointer to the object header structure for the
+ *                              object.
+ *		Failure:	NULL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Jul 13 2008
+ *
+ *-------------------------------------------------------------------------
+ */
+H5O_t *
+H5O_pin(const H5O_loc_t *loc, hid_t dxpl_id)
+{
+    H5O_t       *oh = NULL;             /* Object header */
+    H5O_t       *ret_value = NULL;      /* Return value */
+
+    FUNC_ENTER_NOAPI(NULL)
+
+    /* check args */
+    HDassert(loc);
+
+    /* Get header */
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__NO_FLAGS_SET, FALSE)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, NULL, "unable to protect object header")
+
+    /* Increment the reference count on the object header */
+    /* (which will pin it, if appropriate) */
+    if(H5O_inc_rc(oh) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTINC, NULL, "unable to increment reference count on object header")
+
+    /* Set the return value */
+    ret_value = oh;
+
+done:
+    /* Release the object header from the cache */
+    if(oh && H5O_unprotect(loc, dxpl_id, oh, H5AC__NO_FLAGS_SET) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, NULL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_pin() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_unpin
+ *
+ * Purpose:	Unpin an object header, allowing it to be evicted from the
+ *              metadata cache.
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Jul 13 2008
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_unpin(H5O_t *oh)
+{
+    herr_t ret_value = SUCCEED;      /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* check args */
+    HDassert(oh);
+
+    /* Decrement the reference count on the object header */
+    /* (which will unpin it, if appropriate) */
+    if(H5O_dec_rc(oh) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTDEC, FAIL, "unable to decrement reference count on object header")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_unpin() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_unprotect
+ *
+ * Purpose:	Wrapper around H5AC_unprotect for use during a H5O_protect->
+ *              H5O_msg_append->...->H5O_msg_append->H5O_unprotect sequence of calls
+ *              during an object's creation.
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Dec 31 2002
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_unprotect(const H5O_loc_t *loc, hid_t dxpl_id, H5O_t *oh, unsigned oh_flags)
+{
+    herr_t ret_value = SUCCEED;      /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* check args */
+    HDassert(loc);
+    HDassert(oh);
+
+    /* Unpin the other chunks */
+    if(oh->chunks_pinned && oh->nchunks > 1) {
+        unsigned u;         /* Local index variable */
+
+        /* Sanity check */
+        HDassert(oh->swmr_write);
+
+        /* Iterate over chunks > 0 */
+        for(u = 1; u < oh->nchunks; u++) {
+            if(NULL != oh->chunk[u].chunk_proxy) {
+                /* Release chunk proxy */
+                if(H5AC_unpin_entry(oh->chunk[u].chunk_proxy) < 0)
+                    HGOTO_ERROR(H5E_OHDR, H5E_CANTUNPIN, FAIL, "unable to unpin object header chunk")
+                oh->chunk[u].chunk_proxy = NULL;
+            } /* end if */
+        } /* end for */
+
+        /* Reet the flag from the unprotect */
+        oh->chunks_pinned = FALSE;
+    } /* end if */
+
+    /* Unprotect the object header */
+    if(H5AC_unprotect(loc->file, dxpl_id, H5AC_OHDR, oh->chunk[0].addr, oh, oh_flags) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, FAIL, "unable to release object header")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_unprotect() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_touch_oh
+ *
+ * Purpose:	If FORCE is non-zero then create a modification time message
+ *		unless one already exists.  Then update any existing
+ *		modification time message with the current time.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Robb Matzke
+ *              Monday, July 27, 1998
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_touch_oh(H5F_t *f, hid_t dxpl_id, H5O_t *oh, hbool_t force)
+{
+    H5O_chunk_proxy_t *chk_proxy = NULL;        /* Chunk that message is in */
+    hbool_t chk_dirtied = FALSE;        /* Flag for unprotecting chunk */
+    time_t	now;                    /* Current time */
+    herr_t      ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT
+
+    HDassert(f);
+    HDassert(oh);
+
+    /* Check if this object header is tracking times */
+    if(oh->flags & H5O_HDR_STORE_TIMES) {
+        /* Get current time */
+        now = H5_now();
+
+        /* Check version, to determine how to store time information */
+        if(oh->version == H5O_VERSION_1) {
+            size_t	idx;                    /* Index of modification time message to update */
+
+            /* Look for existing message */
+            for(idx = 0; idx < oh->nmesgs; idx++)
+                if(H5O_MSG_MTIME == oh->mesg[idx].type || H5O_MSG_MTIME_NEW == oh->mesg[idx].type)
+                    break;
+
+            /* Create a new message, if necessary */
+            if(idx == oh->nmesgs) {
+                unsigned mesg_flags = 0;        /* Flags for message in object header */
+
+                /* If we would have to create a new message, but we aren't 'forcing' it, get out now */
+                if(!force)
+                    HGOTO_DONE(SUCCEED);        /*nothing to do*/
+
+                /* Allocate space for the modification time message */
+                if(H5O_msg_alloc(f, dxpl_id, oh, H5O_MSG_MTIME_NEW, &mesg_flags, &now, &idx) < 0)
+                    HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "unable to allocate space for modification time message")
+
+                /* Set the message's flags if appropriate */
+                oh->mesg[idx].flags = (uint8_t)mesg_flags;
+            } /* end if */
+
+            /* Protect chunk */
+            if(NULL == (chk_proxy = H5O_chunk_protect(f, dxpl_id, oh, oh->mesg[idx].chunkno)))
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header chunk")
+
+            /* Allocate 'native' space, if necessary */
+            if(NULL == oh->mesg[idx].native) {
+                if(NULL == (oh->mesg[idx].native = H5FL_MALLOC(time_t)))
+                    HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "memory allocation failed for modification time message")
+            } /* end if */
+
+            /* Update the message */
+            *((time_t *)(oh->mesg[idx].native)) = now;
+
+            /* Mark the message as dirty */
+            oh->mesg[idx].dirty = TRUE;
+            chk_dirtied = TRUE;
+        } /* end if */
+        else {
+            /* XXX: For now, update access time & change fields in the object header */
+            /* (will need to add some code to update modification time appropriately) */
+            oh->atime = oh->ctime = now;
+
+            /* Mark object header as dirty in cache */
+            if(H5AC_mark_entry_dirty(oh) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTMARKDIRTY, FAIL, "unable to mark object header as dirty")
+        } /* end else */
+    } /* end if */
+
+done:
+    /* Release chunk */
+    if(chk_proxy && H5O_chunk_unprotect(f, dxpl_id, chk_proxy, chk_dirtied) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, FAIL, "unable to unprotect object header chunk")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_touch_oh() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_touch
+ *
+ * Purpose:	Touch an object by setting the modification time to the
+ *		current time and marking the object as dirty.  Unless FORCE
+ *		is non-zero, nothing happens if there is no MTIME message in
+ *		the object header.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Robb Matzke
+ *              Monday, July 27, 1998
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_touch(const H5O_loc_t *loc, hbool_t force, hid_t dxpl_id)
+{
+    H5O_t	*oh = NULL;             /* Object header to modify */
+    unsigned 	oh_flags = H5AC__NO_FLAGS_SET; /* Flags for unprotecting object header */
+    herr_t      ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* check args */
+    HDassert(loc);
+
+    /* Get the object header */
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__NO_FLAGS_SET, FALSE)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
+
+    /* Create/Update the modification time message */
+    if(H5O_touch_oh(loc->file, dxpl_id, oh, force) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTSET, FAIL, "unable to update object modificaton time")
+
+    /* Mark object header as changed */
+    oh_flags |= H5AC__DIRTIED_FLAG;
+
+done:
+    if(oh && H5O_unprotect(loc, dxpl_id, oh, oh_flags) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, FAIL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_touch() */
+
+#ifdef H5O_ENABLE_BOGUS
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_bogus_oh
+ *
+ * Purpose:	Create a "bogus" message unless one already exists.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              <koziol@ncsa.uiuc.edu>
+ *              Tuesday, January 21, 2003
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_bogus_oh(H5F_t *f, hid_t dxpl_id, H5O_t *oh, unsigned bogus_id, unsigned mesg_flags)
+{
+    size_t	idx;                /* Local index variable */
+    H5O_msg_class_t *type;	    /* Message class type */
+    herr_t ret_value = SUCCEED;     /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    HDassert(f);
+    HDassert(oh);
+
+    /* Look for existing message */
+    for(idx = 0; idx < oh->nmesgs; idx++)
+        if(H5O_MSG_BOGUS_VALID == oh->mesg[idx].type || H5O_MSG_BOGUS_INVALID == oh->mesg[idx].type)
+            break;
+
+    /* Create a new message */
+    if(idx == oh->nmesgs) {
+        H5O_bogus_t *bogus;             /* Pointer to the bogus information */
+
+        /* Allocate the native message in memory */
+	if(NULL == (bogus = H5MM_malloc(sizeof(H5O_bogus_t))))
+	    HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "memory allocation failed for 'bogus' message")
+
+        /* Update the native value */
+        bogus->u = H5O_BOGUS_VALUE;
+
+	if(bogus_id == H5O_BOGUS_VALID_ID)
+	    type = H5O_MSG_BOGUS_VALID;
+	else if(bogus_id == H5O_BOGUS_INVALID_ID)
+	    type = H5O_MSG_BOGUS_INVALID;
+	else
+	    HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "invalid ID for 'bogus' message")
+
+        /* Allocate space in the object header for bogus message */
+	if(H5O_msg_alloc(f, dxpl_id, oh, type, &mesg_flags, bogus, &idx) < 0)
+	    HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "unable to allocate space for 'bogus' message")
+
+        /* Point to "bogus" information (take it over) */
+	oh->mesg[idx].native = bogus;
+
+        /* Set the appropriate flags for the message */
+        oh->mesg[idx].flags = mesg_flags;
+
+        /* Mark the message and object header as dirty */
+        oh->mesg[idx].dirty = TRUE;
+        oh->cache_info.is_dirty = TRUE;
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_bogus_oh() */
+#endif /* H5O_ENABLE_BOGUS */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_delete
+ *
+ * Purpose:	Delete an object header from a file.  This frees the file
+ *              space used for the object header (and it's continuation blocks)
+ *              and also walks through each header message and asks it to
+ *              remove all the pieces of the file referenced by the header.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Mar 19 2003
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_delete(H5F_t *f, hid_t dxpl_id, haddr_t addr)
+{
+    H5O_t *oh = NULL;           /* Object header information */
+    H5O_loc_t loc;              /* Object location for object to delete */
+    unsigned oh_flags = H5AC__NO_FLAGS_SET; /* Flags for unprotecting object header */
+    hbool_t corked;
+    herr_t ret_value = SUCCEED; /* Return value */
+
+    FUNC_ENTER_NOAPI_TAG(dxpl_id, addr, FAIL)
+
+    /* Check args */
+    HDassert(f);
+    HDassert(H5F_addr_defined(addr));
+
+    /* Set up the object location */
+    loc.file = f;
+    loc.addr = addr;
+    loc.holding_file = FALSE;
+
+    /* Get the object header information */
+    if(NULL == (oh = H5O_protect(&loc, dxpl_id, H5AC__NO_FLAGS_SET, FALSE)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
+
+    /* Delete object */
+    if(H5O_delete_oh(f, dxpl_id, oh) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTDELETE, FAIL, "can't delete object from file")
+
+    /* Uncork cache entries with tag: addr */
+    if(H5AC_cork(f, addr, H5AC__GET_CORKED, &corked) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "unable to retrieve an object's cork status")
+    if(corked)
+        if(H5AC_cork(f, addr, H5AC__UNCORK, NULL) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTUNCORK, FAIL, "unable to uncork an object")
+
+    /* Mark object header as deleted */
+    oh_flags = H5AC__DIRTIED_FLAG | H5AC__DELETED_FLAG | H5AC__FREE_FILE_SPACE_FLAG;
+
+done:
+    if(oh && H5O_unprotect(&loc, dxpl_id, oh, oh_flags) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_PROTECT, FAIL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI_TAG(ret_value, FAIL)
+} /* end H5O_delete() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_delete_oh
+ *
+ * Purpose:	Internal function to:
+ *              Delete an object header from a file.  This frees the file
+ *              space used for the object header (and it's continuation blocks)
+ *              and also walks through each header message and asks it to
+ *              remove all the pieces of the file referenced by the header.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Mar 19 2003
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5O_delete_oh(H5F_t *f, hid_t dxpl_id, H5O_t *oh)
+{
+    H5O_mesg_t *curr_msg;       /* Pointer to current message being operated on */
+    unsigned	u;
+    herr_t ret_value = SUCCEED;   /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT
+
+    /* Check args */
+    HDassert(f);
+    HDassert(oh);
+
+    /* Walk through the list of object header messages, asking each one to
+     * delete any file space used
+     */
+    for(u = 0, curr_msg = &oh->mesg[0]; u < oh->nmesgs; u++, curr_msg++) {
+        /* Free any space referred to in the file from this message */
+        if(H5O_delete_mesg(f, dxpl_id, oh, curr_msg) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTDELETE, FAIL, "unable to delete file space for object header message")
+    } /* end for */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_delete_oh() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_obj_type
+ *
+ * Purpose:	Retrieves the type of object pointed to by `loc'.
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Robb Matzke
+ *              Wednesday, November  4, 1998
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_obj_type(const H5O_loc_t *loc, H5O_type_t *obj_type, hid_t dxpl_id)
+{
+    H5O_t	*oh = NULL;             /* Object header for location */
+    herr_t      ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_NOAPI_TAG(dxpl_id, loc->addr, FAIL)
+
+    /* Load the object header */
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG, FALSE)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
+
+    /* Retrieve the type of the object */
+    if(H5O_obj_type_real(oh, obj_type) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "unable to determine object type")
+
+done:
+    if(oh && H5O_unprotect(loc, dxpl_id, oh, H5AC__NO_FLAGS_SET) < 0)
+	HDONE_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, FAIL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI_TAG(ret_value, FAIL)
+} /* end H5O_obj_type() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_obj_type_real
+ *
+ * Purpose:	Returns the type of object pointed to by `oh'.
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, November 21, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5O_obj_type_real(H5O_t *oh, H5O_type_t *obj_type)
+{
+    const H5O_obj_class_t *obj_class;           /* Class of object for header */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+
+    /* Sanity check */
+    HDassert(oh);
+    HDassert(obj_type);
+
+    /* Look up class for object header */
+    if(NULL == (obj_class = H5O_obj_class_real(oh))) {
+        /* Clear error stack from "failed" class lookup */
+        H5E_clear_stack(NULL);
+
+        /* Set type to "unknown" */
+        *obj_type = H5O_TYPE_UNKNOWN;
+    }
+    else {
+        /* Set object type */
+        *obj_type = obj_class->type;
+    }
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5O_obj_type_real() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_obj_class
+ *
+ * Purpose:	Returns the class of object pointed to by `loc'.
+ *
+ * Return:	Success:	An object class
+ *		Failure:	NULL
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, November  6, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+const H5O_obj_class_t *
+H5O_obj_class(const H5O_loc_t *loc, hid_t dxpl_id)
+{
+    H5O_t	*oh = NULL;                     /* Object header for location */
+    const H5O_obj_class_t *ret_value = NULL;    /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT_TAG(dxpl_id, loc->addr, NULL)
+
+    /* Load the object header */
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG, FALSE)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, NULL, "unable to load object header")
+
+    /* Test whether entry qualifies as a particular type of object */
+    if(NULL == (ret_value = H5O_obj_class_real(oh)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, NULL, "unable to determine object type")
+
+done:
+    if(oh && H5O_unprotect(loc, dxpl_id, oh, H5AC__NO_FLAGS_SET) < 0)
+	HDONE_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, NULL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI_TAG(ret_value, NULL)
+} /* end H5O_obj_class() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_obj_class_real
+ *
+ * Purpose:	Returns the class of object pointed to by `oh'.
+ *
+ * Return:	Success:	An object class
+ *		Failure:	NULL
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, November 21, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static const H5O_obj_class_t *
+H5O_obj_class_real(H5O_t *oh)
+{
+    size_t	i;                      /* Local index variable */
+    const H5O_obj_class_t *ret_value = NULL;   /* Return value */
+
+    FUNC_ENTER_NOAPI(NULL)
+
+    /* Sanity check */
+    HDassert(oh);
+
+    /* Test whether entry qualifies as a particular type of object */
+    /* (Note: loop is in reverse order, to test specific objects first) */
+    for(i = NELMTS(H5O_obj_class_g); i > 0; --i) {
+        htri_t	isa;            /* Is entry a particular type? */
+
+        if((isa = (H5O_obj_class_g[i - 1]->isa)(oh)) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, NULL, "unable to determine object type")
+        else if(isa)
+            HGOTO_DONE(H5O_obj_class_g[i - 1])
+    }
+
+    if(0 == i)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, NULL, "unable to determine object type")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_obj_class_real() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_loc
+ *
+ * Purpose:	Gets the object location for an object given its ID.
+ *
+ * Return:	Success:	Pointer to H5O_loc_t
+ *		Failure:	NULL
+ *
+ * Programmer:	James Laird
+ *		July 25 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+H5O_loc_t *
+H5O_get_loc(hid_t object_id)
+{
+    H5O_loc_t   *ret_value = NULL;      /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT
+
+    switch(H5I_get_type(object_id)) {
+        case H5I_GROUP:
+            if(NULL == (ret_value = H5O_OBJ_GROUP->get_oloc(object_id)))
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, NULL, "unable to get object location from group ID")
+            break;
+
+        case H5I_DATASET:
+            if(NULL == (ret_value = H5O_OBJ_DATASET->get_oloc(object_id)))
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, NULL, "unable to get object location from dataset ID")
+            break;
+
+        case H5I_DATATYPE:
+            if(NULL == (ret_value = H5O_OBJ_DATATYPE->get_oloc(object_id)))
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, NULL, "unable to get object location from datatype ID")
+            break;
+
+        case H5I_UNINIT:
+        case H5I_BADID:
+        case H5I_FILE:
+        case H5I_DATASPACE:
+        case H5I_ATTR:
+        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_OHDR, H5E_BADTYPE, NULL, "invalid object type")
+    } /* end switch */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_get_loc() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_loc_reset
+ *
+ * Purpose:	Reset a object location to an empty state
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, September 19, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_loc_reset(H5O_loc_t *loc)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+
+    /* Check arguments */
+    HDassert(loc);
+
+    /* Clear the object location to an empty state */
+    HDmemset(loc, 0, sizeof(H5O_loc_t));
+    loc->addr = HADDR_UNDEF;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5O_loc_reset() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5O_loc_copy
+ *
+ * Purpose:     Copy object location information
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *              koziol@ncsa.uiuc.edu
+ *              Monday, September 19, 2005
+ *
+ * Notes:       'depth' parameter determines how much of the group entry
+ *              structure we want to copy.  The values are:
+ *                  H5_COPY_SHALLOW - Copy all the field values from the source
+ *                      to the destination, but not copying objects pointed to.
+ *                      (Destination "takes ownership" of objects pointed to)
+ *                  H5_COPY_DEEP - Copy all the fields from the source to
+ *                      the destination, deep copying objects pointed to.
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_loc_copy(H5O_loc_t *dst, H5O_loc_t *src, H5_copy_depth_t depth)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+
+    /* Check arguments */
+    HDassert(src);
+    HDassert(dst);
+    HDassert(depth == H5_COPY_SHALLOW || depth == H5_COPY_DEEP);
+
+    /* Copy the top level information */
+    HDmemcpy(dst, src, sizeof(H5O_loc_t));
+
+    /* Deep copy the names */
+    if(depth == H5_COPY_DEEP) {
+        /* If the original entry was holding open the file, this one should
+         * hold it open, too.
+         */
+        if(src->holding_file)
+            H5F_INCR_NOPEN_OBJS(dst->file);
+    }
+    else if(depth == H5_COPY_SHALLOW) {
+        H5O_loc_reset(src);
+    }
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5O_loc_copy() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_loc_hold_file
+ *
+ * Purpose:	Have this object header hold a file open until it is
+ *              released.
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	James Laird
+ *              Wednesday, August 16, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_loc_hold_file(H5O_loc_t *loc)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+
+    /* Check arguments */
+    HDassert(loc);
+    HDassert(loc->file);
+
+    /* If this location is not already holding its file open, do so. */
+    if(!loc->holding_file) {
+        H5F_INCR_NOPEN_OBJS(loc->file);
+        loc->holding_file = TRUE;
+    }
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5O_loc_hold_file() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_loc_free
+ *
+ * Purpose:	Release resources used by this object header location.
+ *              Not to be confused with H5O_close; this is used on
+ *              locations that don't correspond to open objects.
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	James Laird
+ *              Wednesday, August 16, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_loc_free(H5O_loc_t *loc)
+{
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_NOAPI_NOINIT
+
+    /* Check arguments */
+    HDassert(loc);
+
+    /* If this location is holding its file open try to close the file. */
+    if(loc->holding_file) {
+        H5F_DECR_NOPEN_OBJS(loc->file);
+        loc->holding_file = FALSE;
+        if(H5F_NOPEN_OBJS(loc->file) <= 0) {
+            if(H5F_try_close(loc->file, NULL) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTCLOSEFILE, FAIL, "can't close file")
+        }
+    }
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_loc_free() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_hdr_info
+ *
+ * Purpose:	Retrieve the object header information for an object
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *		September 22 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_get_hdr_info(const H5O_loc_t *loc, hid_t dxpl_id, H5O_hdr_info_t *hdr)
+{
+    H5O_t *oh = NULL;                   /* Object header */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* Check args */
+    HDassert(loc);
+    HDassert(hdr);
+
+    /* Reset the object header info structure */
+    HDmemset(hdr, 0, sizeof(*hdr));
+
+    /* Get the object header */
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG, FALSE)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header")
+
+    /* Get the information for the object header */
+    if(H5O_get_hdr_info_real(oh, hdr) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't retrieve object header info")
+
+done:
+    if(oh && H5O_unprotect(loc, dxpl_id, oh, H5AC__NO_FLAGS_SET) < 0)
+	HDONE_ERROR(H5E_OHDR, H5E_PROTECT, FAIL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_get_hdr_info() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_hdr_info_real
+ *
+ * Purpose:	Internal routine to retrieve the object header information for an object
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *		September 22 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5O_get_hdr_info_real(const H5O_t *oh, H5O_hdr_info_t *hdr)
+{
+    const H5O_mesg_t *curr_msg;         /* Pointer to current message being operated on */
+    const H5O_chunk_t *curr_chunk;	/* Pointer to current message being operated on */
+    unsigned u;                         /* Local index variable */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+
+    /* Check args */
+    HDassert(oh);
+    HDassert(hdr);
+
+    /* Set the version for the object header */
+    hdr->version = oh->version;
+
+    /* Set the number of messages & chunks */
+    H5_CHECKED_ASSIGN(hdr->nmesgs, unsigned, oh->nmesgs, size_t);
+    H5_CHECKED_ASSIGN(hdr->nchunks, unsigned, oh->nchunks, size_t);
+
+    /* Set the status flags */
+    hdr->flags = oh->flags;
+
+    /* Iterate over all the messages, accumulating message size & type information */
+    hdr->space.meta = (hsize_t)H5O_SIZEOF_HDR(oh) + (hsize_t)(H5O_SIZEOF_CHKHDR_OH(oh) * (oh->nchunks - 1));
+    hdr->space.mesg = 0;
+    hdr->space.free = 0;
+    hdr->mesg.present = 0;
+    hdr->mesg.shared = 0;
+    for(u = 0, curr_msg = &oh->mesg[0]; u < oh->nmesgs; u++, curr_msg++) {
+        uint64_t type_flag;             /* Flag for message type */
+
+        /* Accumulate space usage information, based on the type of message */
+        if(H5O_NULL_ID == curr_msg->type->id)
+            hdr->space.free += (hsize_t)((size_t)H5O_SIZEOF_MSGHDR_OH(oh) + curr_msg->raw_size);
+        else if(H5O_CONT_ID == curr_msg->type->id)
+            hdr->space.meta += (hsize_t)((size_t)H5O_SIZEOF_MSGHDR_OH(oh) + curr_msg->raw_size);
+        else {
+            hdr->space.meta += (hsize_t)H5O_SIZEOF_MSGHDR_OH(oh);
+            hdr->space.mesg += curr_msg->raw_size;
+        } /* end else */
+
+        /* Set flag to indicate presence of message type */
+        type_flag = ((uint64_t)1) << curr_msg->type->id;
+        hdr->mesg.present |= type_flag;
+
+        /* Set flag if the message is shared in some way */
+        if(curr_msg->flags & H5O_MSG_FLAG_SHARED)                                   \
+            hdr->mesg.shared |= type_flag;
+    } /* end for */
+
+    /* Iterate over all the chunks, adding any gaps to the free space */
+    hdr->space.total = 0;
+    for(u = 0, curr_chunk = &oh->chunk[0]; u < oh->nchunks; u++, curr_chunk++) {
+        /* Accumulate the size of the header on disk */
+        hdr->space.total += curr_chunk->size;
+
+        /* If the chunk has a gap, add it to the free space */
+        hdr->space.free += curr_chunk->gap;
+    } /* end for */
+
+    /* Sanity check that all the bytes are accounted for */
+    HDassert(hdr->space.total == (hdr->space.free + hdr->space.meta + hdr->space.mesg));
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5O_get_hdr_info_real() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_info
+ *
+ * Purpose:	Retrieve the information for an object
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *		November 21 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_get_info(const H5O_loc_t *loc, hid_t dxpl_id, hbool_t want_ih_info,
+    H5O_info_t *oinfo)
+{
+    const H5O_obj_class_t *obj_class;   /* Class of object for header */
+    H5O_t *oh = NULL;                   /* Object header */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_TAG(dxpl_id, loc->addr, FAIL)
+
+    /* Check args */
+    HDassert(loc);
+    HDassert(oinfo);
+
+    /* Get the object header */
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG, FALSE)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
+
+    /* Reset the object info structure */
+    HDmemset(oinfo, 0, sizeof(*oinfo));
+
+    /* Retrieve the file's fileno */
+    H5F_GET_FILENO(loc->file, oinfo->fileno);
+
+    /* Set the object's address */
+    oinfo->addr = loc->addr;
+
+    /* Get class for object */
+    if(NULL == (obj_class = H5O_obj_class_real(oh)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "unable to determine object class")
+
+    /* Retrieve the type of the object */
+    oinfo->type = obj_class->type;
+
+    /* Set the object's reference count */
+    oinfo->rc = oh->nlink;
+
+    /* Get modification time for object */
+    if(oh->version > H5O_VERSION_1) {
+        oinfo->atime = oh->atime;
+        oinfo->mtime = oh->mtime;
+        oinfo->ctime = oh->ctime;
+        oinfo->btime = oh->btime;
+    } /* end if */
+    else {
+        htri_t	exists;                 /* Flag if header message of interest exists */
+
+        /* No information for access & modification fields */
+        /* (we stopped updating the "modification time" header message for
+         *      raw data changes, so the "modification time" header message
+         *      is closest to the 'change time', in POSIX terms - QAK)
+         */
+        oinfo->atime = 0;
+        oinfo->mtime = 0;
+        oinfo->btime = 0;
+
+        /* Might be information for modification time */
+        if((exists = H5O_msg_exists_oh(oh, H5O_MTIME_ID)) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_NOTFOUND, FAIL, "unable to check for MTIME message")
+        if(exists > 0) {
+            /* Get "old style" modification time info */
+            if(NULL == H5O_msg_read_oh(loc->file, dxpl_id, oh, H5O_MTIME_ID, &oinfo->ctime))
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't read MTIME message")
+        } /* end if */
+        else {
+            /* Check for "new style" modification time info */
+            if((exists = H5O_msg_exists_oh(oh, H5O_MTIME_NEW_ID)) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_NOTFOUND, FAIL, "unable to check for MTIME_NEW message")
+            if(exists > 0) {
+                /* Get "new style" modification time info */
+                if(NULL == H5O_msg_read_oh(loc->file, dxpl_id, oh, H5O_MTIME_NEW_ID, &oinfo->ctime))
+                    HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't read MTIME_NEW message")
+            } /* end if */
+            else
+                oinfo->ctime = 0;
+        } /* end else */
+    } /* end else */
+
+    /* Get the information for the object header */
+    if(H5O_get_hdr_info_real(oh, &oinfo->hdr) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't retrieve object header info")
+
+    /* Retrieve # of attributes */
+    if(H5O_attr_count_real(loc->file, dxpl_id, oh, &oinfo->num_attrs) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't retrieve attribute count")
+
+    /* Get B-tree & heap metadata storage size, if requested */
+    if(want_ih_info) {
+        /* Check for 'bh_info' callback for this type of object */
+        if(obj_class->bh_info) {
+            /* Call the object's class 'bh_info' routine */
+            if((obj_class->bh_info)(loc, dxpl_id, oh, &oinfo->meta_size.obj) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't retrieve object's btree & heap info")
+        } /* end if */
+
+        /* Get B-tree & heap info for any attributes */
+        if(oinfo->num_attrs > 0) {
+            if(H5O_attr_bh_info(loc->file, dxpl_id, oh, &oinfo->meta_size.attr) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't retrieve attribute btree & heap info")
+        } /* end if */
+    } /* end if */
+
+done:
+    if(oh && H5O_unprotect(loc, dxpl_id, oh, H5AC__NO_FLAGS_SET) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, FAIL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI_TAG(ret_value, FAIL)
+} /* end H5O_get_info() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_create_plist
+ *
+ * Purpose:	Retrieve the object creation properties for an object
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *		November 28 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_get_create_plist(const H5O_loc_t *loc, hid_t dxpl_id, H5P_genplist_t *oc_plist)
+{
+    H5O_t *oh = NULL;                   /* Object header */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* Check args */
+    HDassert(loc);
+    HDassert(oc_plist);
+
+    /* Get the object header */
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG, FALSE)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
+
+    /* Set property values, if they were used for the object */
+    if(oh->version > H5O_VERSION_1) {
+        uint8_t ohdr_flags;             /* "User-visible" object header status flags */
+
+        /* Set attribute storage values */
+        if(H5P_set(oc_plist, H5O_CRT_ATTR_MAX_COMPACT_NAME, &oh->max_compact) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTSET, FAIL, "can't set max. # of compact attributes in property list")
+        if(H5P_set(oc_plist, H5O_CRT_ATTR_MIN_DENSE_NAME, &oh->min_dense) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTSET, FAIL, "can't set min. # of dense attributes in property list")
+
+        /* Mask off non-"user visible" flags */
+        ohdr_flags = oh->flags & (H5O_HDR_ATTR_CRT_ORDER_TRACKED | H5O_HDR_ATTR_CRT_ORDER_INDEXED | H5O_HDR_STORE_TIMES);
+
+        /* Set object header flags */
+        if(H5P_set(oc_plist, H5O_CRT_OHDR_FLAGS_NAME, &ohdr_flags) < 0)
+            HGOTO_ERROR(H5E_PLIST, H5E_CANTSET, FAIL, "can't set object header flags")
+    } /* end if */
+
+done:
+    if(oh && H5O_unprotect(loc, dxpl_id, oh, H5AC__NO_FLAGS_SET) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, FAIL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_get_create_plist() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_nlinks
+ *
+ * Purpose:	Retrieve the number of link messages read in from the file
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *		March 11 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_get_nlinks(const H5O_loc_t *loc, hid_t dxpl_id, hsize_t *nlinks)
+{
+    H5O_t *oh = NULL;                   /* Object header */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* Check args */
+    HDassert(loc);
+    HDassert(nlinks);
+
+    /* Get the object header */
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG, FALSE)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
+
+    /* Retrieve the # of link messages seen when the object header was loaded */
+    *nlinks = oh->link_msgs_seen;
+
+done:
+    if(oh && H5O_unprotect(loc, dxpl_id, oh, H5AC__NO_FLAGS_SET) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, FAIL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_get_nlinks() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_obj_create
+ *
+ * Purpose:	Creates an object, in an abstract manner.
+ *
+ * Return:	Success:	Pointer to object opened
+ *		Failure:	NULL
+ *
+ * Programmer:	Quincey Koziol
+ *		April 9 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+void *
+H5O_obj_create(H5F_t *f, H5O_type_t obj_type, void *crt_info, H5G_loc_t *obj_loc,
+    hid_t dxpl_id)
+{
+    size_t u;                           /* Local index variable */
+    void *ret_value = NULL;             /* Return value */
+
+    FUNC_ENTER_NOAPI(NULL)
+
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(obj_type >= H5O_TYPE_GROUP && obj_type <= H5O_TYPE_NAMED_DATATYPE);
+    HDassert(crt_info);
+    HDassert(obj_loc);
+
+    /* Iterate through the object classes */
+    for(u = 0; u < NELMTS(H5O_obj_class_g); u++) {
+        /* Check for correct type of object to create */
+	if(H5O_obj_class_g[u]->type == obj_type) {
+            /* Call the object class's 'create' routine */
+            HDassert(H5O_obj_class_g[u]->create);
+            if(NULL == (ret_value = H5O_obj_class_g[u]->create(f, crt_info, obj_loc, dxpl_id)))
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTOPENOBJ, NULL, "unable to open object")
+
+            /* Break out of loop */
+            break;
+        } /* end if */
+    } /* end for */
+    HDassert(ret_value);
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_obj_create() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_oh_addr
+ *
+ * Purpose:	Retrieve the address of the object header
+ *
+ * Note:	This routine participates in the "Inlining C struct access"
+ *		pattern, don't call it directly, use the appropriate macro
+ *		defined in H5Oprivate.h.
+ *
+ * Return:	Success:	Valid haddr_t
+ *		Failure:	HADDR_UNDEF
+ *
+ * Programmer:	Quincey Koziol
+ *		March 15 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+haddr_t
+H5O_get_oh_addr(const H5O_t *oh)
+{
+    /* Use FUNC_ENTER_NOAPI_NOINIT_NOERR here to avoid performance issues */
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+
+    HDassert(oh);
+    HDassert(oh->chunk);
+
+    FUNC_LEAVE_NOAPI(oh->chunk[0].addr)
+} /* end H5O_get_oh_addr() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_rc_and_type
+ *
+ * Purpose:	Retrieve an object's reference count and type
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *		November  4 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_get_rc_and_type(const H5O_loc_t *loc, hid_t dxpl_id, unsigned *rc, H5O_type_t *otype)
+{
+    H5O_t *oh = NULL;                   /* Object header */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* Check args */
+    HDassert(loc);
+
+    /* Get the object header */
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG, FALSE)))
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to load object header")
+
+    /* Set the object's reference count */
+    if(rc)
+        *rc = oh->nlink;
+
+    /* Retrieve the type of the object */
+    if(otype)
+        if(H5O_obj_type_real(oh, otype) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, FAIL, "unable to determine object type")
+
+done:
+    if(oh && H5O_unprotect(loc, dxpl_id, oh, H5AC__NO_FLAGS_SET) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, FAIL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_get_rc_and_type() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5O_free_visit_visited
+ *
+ * Purpose:     Free the key for an object visited during a group traversal
+ *
+ * Return:      Non-negative on success, negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *	        Nov 25, 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5O_free_visit_visited(void *item, void H5_ATTR_UNUSED *key, void H5_ATTR_UNUSED *operator_data/*in,out*/)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+
+    item = H5FL_FREE(H5_obj_t, item);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5O_free_visit_visited() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_visit_cb
+ *
+ * Purpose:     Callback function for recursively visiting objects from a group
+ *
+ * Return:	Success:        Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *	        Nov 25, 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5O_visit_cb(hid_t H5_ATTR_UNUSED group, const char *name, const H5L_info_t *linfo,
+    void *_udata)
+{
+    H5O_iter_visit_ud_t *udata = (H5O_iter_visit_ud_t *)_udata;     /* User data for callback */
+    H5G_loc_t   obj_loc;                /* Location of object */
+    H5G_name_t  obj_path;            	/* Object's group hier. path */
+    H5O_loc_t   obj_oloc;            	/* Object's object location */
+    hbool_t     obj_found = FALSE;      /* Object at 'name' found */
+    herr_t ret_value = H5_ITER_CONT;    /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT
+
+    /* Sanity check */
+    HDassert(name);
+    HDassert(linfo);
+    HDassert(udata);
+
+    /* Check if this is a hard link */
+    if(linfo->type == H5L_TYPE_HARD) {
+        H5_obj_t obj_pos;       /* Object "position" for this object */
+
+        /* Set up opened group location to fill in */
+        obj_loc.oloc = &obj_oloc;
+        obj_loc.path = &obj_path;
+        H5G_loc_reset(&obj_loc);
+
+        /* Find the object using the LAPL passed in */
+        /* (Correctly handles mounted files) */
+        if(H5G_loc_find(udata->start_loc, name, &obj_loc/*out*/, udata->lapl_id, udata->dxpl_id) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_NOTFOUND, H5_ITER_ERROR, "object not found")
+        obj_found = TRUE;
+
+        /* Construct unique "position" for this object */
+        H5F_GET_FILENO(obj_oloc.file, obj_pos.fileno);
+        obj_pos.addr = obj_oloc.addr;
+
+        /* Check if we've seen the object the link references before */
+        if(NULL == H5SL_search(udata->visited, &obj_pos)) {
+            H5O_info_t oinfo;           /* Object info */
+
+            /* Get the object's info */
+            if(H5O_get_info(&obj_oloc, udata->dxpl_id, TRUE, &oinfo) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, H5_ITER_ERROR, "unable to get object info")
+
+            /* Make the application callback */
+            ret_value = (udata->op)(udata->obj_id, name, &oinfo, udata->op_data);
+
+            /* Check for continuing to visit objects */
+            if(ret_value == H5_ITER_CONT) {
+                /* If its ref count is > 1, we add it to the list of visited objects */
+                /* (because it could come up again during traversal) */
+                if(oinfo.rc > 1) {
+                    H5_obj_t *new_node;                  /* New object node for visited list */
+
+                    /* Allocate new object "position" node */
+                    if((new_node = H5FL_MALLOC(H5_obj_t)) == NULL)
+                        HGOTO_ERROR(H5E_OHDR, H5E_NOSPACE, H5_ITER_ERROR, "can't allocate object node")
+
+                    /* Set node information */
+                    *new_node = obj_pos;
+
+                    /* Add to list of visited objects */
+                    if(H5SL_insert(udata->visited, new_node, new_node) < 0)
+                        HGOTO_ERROR(H5E_OHDR, H5E_CANTINSERT, H5_ITER_ERROR, "can't insert object node into visited list")
+                } /* end if */
+            } /* end if */
+        } /* end if */
+    } /* end if */
+
+done:
+    /* Release resources */
+    if(obj_found && H5G_loc_free(&obj_loc) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTRELEASE, H5_ITER_ERROR, "can't free location")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_visit_cb() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_visit
+ *
+ * Purpose:	Recursively visit an object and all the objects reachable
+ *              from it.  If the starting object is a group, all the objects
+ *              linked to from that group will be visited.  Links within
+ *              each group are visited according to the order within the
+ *              specified index (unless the specified index does not exist for
+ *              a particular group, then the "name" index is used).
+ *
+ *              NOTE: Soft links and user-defined links are ignored during
+ *              this operation.
+ *
+ *              NOTE: Each _object_ reachable from the initial group will only
+ *              be visited once.  If multiple hard links point to the same
+ *              object, the first link to the object's path (according to the
+ *              iteration index and iteration order given) will be used to in
+ *              the callback about the object.
+ *
+ * Return:	Success:	The return value of the first operator that
+ *				returns non-zero, or zero if all members were
+ *				processed with no operator returning non-zero.
+ *
+ *		Failure:	Negative if something goes wrong within the
+ *				library, or the negative value returned by one
+ *				of the operators.
+ *
+ * Programmer:	Quincey Koziol
+ *		November 24 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_visit(hid_t loc_id, const char *obj_name, H5_index_t idx_type,
+    H5_iter_order_t order, H5O_iterate_t op, void *op_data, hid_t lapl_id,
+    hid_t dxpl_id)
+{
+    H5O_iter_visit_ud_t udata;  /* User data for callback */
+    H5G_loc_t	loc;            /* Location of reference object */
+    H5G_loc_t   obj_loc;        /* Location used to open object */
+    H5G_name_t  obj_path;       /* Opened object group hier. path */
+    H5O_loc_t   obj_oloc;       /* Opened object object location */
+    hbool_t     loc_found = FALSE;      /* Entry at 'name' found */
+    H5O_info_t  oinfo;          /* Object info struct */
+    hid_t       obj_id = (-1);  /* ID of object */
+    herr_t      ret_value = FAIL;       /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* Portably initialize user data struct to zeros */
+    HDmemset(&udata, 0, sizeof(udata));
+
+    /* Check args */
+    if(H5G_loc(loc_id, &loc) < 0)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a location")
+
+    /* Set up opened group location to fill in */
+    obj_loc.oloc = &obj_oloc;
+    obj_loc.path = &obj_path;
+    H5G_loc_reset(&obj_loc);
+
+    /* Find the object's location */
+    if(H5G_loc_find(&loc, obj_name, &obj_loc/*out*/, lapl_id, dxpl_id) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_NOTFOUND, FAIL, "object not found")
+    loc_found = TRUE;
+
+    /* Get the object's info */
+    if(H5O_get_info(&obj_oloc, dxpl_id, TRUE, &oinfo) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "unable to get object info")
+
+    /* Open the object */
+    /* (Takes ownership of the obj_loc information) */
+    if((obj_id = H5O_open_by_loc(&obj_loc, lapl_id, dxpl_id, TRUE)) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTOPENOBJ, FAIL, "unable to open object")
+
+    /* Make callback for starting object */
+    if((ret_value = op(obj_id, ".", &oinfo, op_data)) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_BADITER, FAIL, "can't visit objects")
+
+    /* Check return value of first callback */
+    if(ret_value != H5_ITER_CONT)
+        HGOTO_DONE(ret_value);
+
+    /* Check for object being a group */
+    if(oinfo.type == H5O_TYPE_GROUP) {
+        H5G_loc_t	start_loc;          /* Location of starting group */
+
+        /* Get the location of the starting group */
+        if(H5G_loc(obj_id, &start_loc) < 0)
+            HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a location")
+
+        /* Set up user data for visiting links */
+        udata.obj_id = obj_id;
+        udata.start_loc = &start_loc;
+        udata.lapl_id = lapl_id;
+        udata.dxpl_id = dxpl_id;
+        udata.op = op;
+        udata.op_data = op_data;
+
+        /* Create skip list to store visited object information */
+        if((udata.visited = H5SL_create(H5SL_TYPE_OBJ, NULL)) == NULL)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTCREATE, FAIL, "can't create skip list for visited objects")
+
+        /* If its ref count is > 1, we add it to the list of visited objects */
+        /* (because it could come up again during traversal) */
+        if(oinfo.rc > 1) {
+            H5_obj_t *obj_pos;                  /* New object node for visited list */
+
+            /* Allocate new object "position" node */
+            if((obj_pos = H5FL_MALLOC(H5_obj_t)) == NULL)
+                HGOTO_ERROR(H5E_OHDR, H5E_NOSPACE, FAIL, "can't allocate object node")
+
+            /* Construct unique "position" for this object */
+            obj_pos->fileno = oinfo.fileno;
+            obj_pos->addr = oinfo.addr;
+
+            /* Add to list of visited objects */
+            if(H5SL_insert(udata.visited, obj_pos, obj_pos) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_CANTINSERT, FAIL, "can't insert object node into visited list")
+        } /* end if */
+
+        /* Call internal group visitation routine */
+        if((ret_value = H5G_visit(obj_id, ".", idx_type, order, H5O_visit_cb, &udata, lapl_id, dxpl_id)) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_BADITER, FAIL, "object visitation failed")
+    } /* end if */
+
+done:
+    if(obj_id > 0) {
+        if(H5I_dec_app_ref(obj_id) < 0)
+            HDONE_ERROR(H5E_OHDR, H5E_CANTRELEASE, FAIL, "unable to close object")
+    } /* end if */
+    else if(loc_found && H5G_loc_free(&obj_loc) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTRELEASE, FAIL, "can't free location")
+    if(udata.visited)
+        H5SL_destroy(udata.visited, H5O_free_visit_visited, NULL);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_visit() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_inc_rc
+ *
+ * Purpose:	Increments the reference count on an object header
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Jul 13 2008
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_inc_rc(H5O_t *oh)
+{
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* check args */
+    HDassert(oh);
+
+    /* Pin the object header when the reference count goes above 0 */
+    if(oh->rc == 0)
+        if(H5AC_pin_protected_entry(oh) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTPIN, FAIL, "unable to pin object header")
+
+    /* Increment reference count */
+    oh->rc++;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_inc_rc() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_dec_rc
+ *
+ * Purpose:	Decrements the reference count on an object header
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Jul 13 2008
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_dec_rc(H5O_t *oh)
+{
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* check args */
+    HDassert(oh);
+
+    /* Decrement reference count */
+    oh->rc--;
+
+    /* Unpin the object header when the reference count goes back to 0 */
+    if(oh->rc == 0)
+        if(H5AC_unpin_entry(oh) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTUNPIN, FAIL, "unable to unpin object header")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_dec_rc() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:   H5O_dec_rc_by_loc
+ *
+ * Purpose:    Decrement the refcount of an object header, using its
+ *              object location information.
+ *
+ * Return:     Non-negative on success/Negative on failure
+ *
+ * Programmer: Quincey Koziol
+ *             koziol@hdfgroup.org
+ *             Oct 08 2010
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_dec_rc_by_loc(const H5O_loc_t *loc, hid_t dxpl_id)
+{
+    H5O_t       *oh = NULL;             /* Object header */
+    herr_t      ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    /* check args */
+    HDassert(loc);
+
+    /* Get header */
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC__READ_ONLY_FLAG, FALSE)))
+       HGOTO_ERROR(H5E_OHDR, H5E_CANTPROTECT, FAIL, "unable to protect object header")
+
+    /* Decrement the reference count on the object header */
+    /* (which will unpin it, if appropriate) */
+    if(H5O_dec_rc(oh) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTDEC, FAIL, "unable to decrement reference count on object header")
+
+done:
+    /* Release the object header from the cache */
+    if(oh && H5O_unprotect(loc, dxpl_id, oh, H5AC__NO_FLAGS_SET) < 0)
+        HDONE_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, FAIL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_dec_rc_by_loc() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_proxy
+ *
+ * Purpose:	Retrieve the proxy for the object header.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		July 24 2016
+ *
+ *-------------------------------------------------------------------------
+ */
+H5AC_proxy_entry_t *
+H5O_get_proxy(const H5O_t *oh)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOERR
+
+    /* Check args */
+    HDassert(oh);
+
+    FUNC_LEAVE_NOAPI(oh->proxy)
+} /* end H5O_get_proxy() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O__free
+ *
+ * Purpose:	Destroys an object header.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Jan 15 2003
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O__free(H5O_t *oh)
+{
+    unsigned	u;                      /* Local index variable */
+    herr_t      ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_PACKAGE
+
+    /* check args */
+    HDassert(oh);
+    HDassert(0 == oh->rc);
+
+    /* Destroy chunks */
+    if(oh->chunk) {
+        for(u = 0; u < oh->nchunks; u++)
+            oh->chunk[u].image = H5FL_BLK_FREE(chunk_image, oh->chunk[u].image);
+
+        oh->chunk = (H5O_chunk_t *)H5FL_SEQ_FREE(H5O_chunk_t, oh->chunk);
+    } /* end if */
+
+    /* Destroy messages */
+    if(oh->mesg) {
+        for(u = 0; u < oh->nmesgs; u++) {
+#ifndef NDEBUG
+            /* Verify that message is clean, unless it could have been marked
+             * dirty by decoding */
+            if(oh->ndecode_dirtied && oh->mesg[u].dirty)
+                oh->ndecode_dirtied--;
+            else
+                HDassert(oh->mesg[u].dirty == 0);
+#endif /* NDEBUG */
+
+            H5O_msg_free_mesg(&oh->mesg[u]);
+        } /* end for */
+
+        /* Make sure we accounted for all the messages dirtied by decoding */
+        HDassert(!oh->ndecode_dirtied);
+
+        oh->mesg = (H5O_mesg_t *)H5FL_SEQ_FREE(H5O_mesg_t, oh->mesg);
+    } /* end if */
+
+    /* Destroy the proxy */
+    if(oh->proxy)
+        if(H5AC_proxy_entry_dest(oh->proxy) < 0)
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "unable to destroy virtual entry used for proxy")
+
+    /* destroy object header */
+    oh = H5FL_FREE(H5O_t, oh);
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O__free() */