[svn-r11712] Purpose:

    New feature

Description:
    Check in baseline for compact group revisions, which radically revises the
source code for managing groups and object headers.

WARNING!!!!  WARNING!!!!  WARNING!!!!  WARNING!!!!  WARNING!!!!  WARNING!!!!
WARNING!!!!  WARNING!!!!  WARNING!!!!  WARNING!!!!  WARNING!!!!  WARNING!!!!

    This initiates the "unstable" phase of the 1.7.x branch, leading up
to the 1.8.0 release.  Please test this code, but do _NOT_ keep files created
with it - the format will change again before the release and you will not
be able to read your old files!!!

WARNING!!!!  WARNING!!!!  WARNING!!!!  WARNING!!!!  WARNING!!!!  WARNING!!!!
WARNING!!!!  WARNING!!!!  WARNING!!!!  WARNING!!!!  WARNING!!!!  WARNING!!!!


Solution:
    There's too many changes to really describe them all, but some of them
include:
    - Stop abusing the H5G_entry_t structure and split it into two separate
        structures for non-symbol table node use within the library: H5O_loc_t
        for object locations in a file and H5G_name_t to store the path to
        an opened object.  H5G_entry_t is now only used for storing symbol
        table entries on disk.

    - Retire H5G_namei() in favor of a more general mechanism for traversing
        group paths and issuing callbacks on objects located.  This gets us out
        of the business of hacking H5G_namei() for new features, generally.

    - Revised H5O* routines to take a H5O_loc_t instead of H5G_entry_t

    - Lots more...

Platforms tested:
    h5committested and maybe another dozen configurations.... :-)

1 files changed, 476 insertions, 147 deletions

diff --git a/src/H5Gstab.c b/src/H5Gstab.c
index b63e1cd..926ff7f 100644
--- a/src/H5Gstab.c
+++ b/src/H5Gstab.c
@@ -26,87 +26,170 @@
 #include "H5Fpkg.h"		/* File access				*/
 #include "H5Gpkg.h"		/* Groups		  		*/
 #include "H5HLprivate.h"	/* Local Heaps				*/
+#include "H5Iprivate.h"		/* IDs			  		*/
 #include "H5MMprivate.h"	/* Memory management			*/
 
+/* Private typedefs */
+/* User data for finding a name in the link messages */
+typedef struct {
+    /* downward */
+    H5F_t      *f;              /* Pointer to file for insertion */
+    const char *name;           /* Name to search for */
+
+    /* upward */
+    H5G_entry_t *ent;           /* Entry to update when match found */
+} H5G_stab_ud1_t;
+
+/* User data for finding object info from B-tree */
+typedef struct {
+    /* downward */
+    H5O_loc_t *grp_oloc;        /* Object location of group */
+    hid_t       dxpl_id;        /* DXPL during operation */
+    haddr_t     heap_addr;      /* Local heap address for group */
+
+    /* upward */
+    H5G_stat_t *statbuf;        /* Caller's statbuf */
+} H5G_stab_fnd_ud1_t;
+
+/* User data for finding link information from B-tree */
+typedef struct {
+    /* downward */
+    H5F_t      *file;           /* Pointer to file for query */
+    hid_t       dxpl_id;        /* DXPL during operation */
+    const char *name;           /* Name to search for */
+    haddr_t     heap_addr;      /* Local heap address for group */
+
+    /* upward */
+    H5O_link_t *lnk;            /* Caller's link location */
+} H5G_stab_fnd_ud2_t;
+
+/* User data for finding object location from B-tree */
+typedef struct {
+    /* downward */
+    H5F_t      *file;           /* Pointer to file for query */
+    size_t      size;           /* Buffer size for link value */
+    haddr_t     heap_addr;      /* Local heap address for group */
+    hid_t       dxpl_id;        /* DXPL during operation */
+
+    /* upward */
+    char *buf;                  /* Buffer to fill with link value */
+} H5G_stab_fnd_ud3_t;
+
 /* Private prototypes */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5G_stab_create
+ * Function:	H5G_stab_create_components
  *
- * Purpose:	Creates a new empty symbol table (object header, name heap,
+ * Purpose:	Creates the components for a new, empty, symbol table (name heap
  *		and B-tree).  The caller can specify an initial size for the
- *		name heap.  The object header of the group is opened for
- *		write access.
+ *		name heap.
  *
  *		In order for the B-tree to operate correctly, the first
  *		item in the heap is the empty string, and must appear at
  *		heap offset zero.
  *
- * Errors:
- *
  * Return:	Non-negative on success/Negative on failure
  *
- * Programmer:	Robb Matzke
- *		matzke@llnl.gov
- *		Aug  1 1997
- *
- * Modifications:
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Nov  7 2005
  *
  *-------------------------------------------------------------------------
  */
 herr_t
-H5G_stab_create(H5F_t *f, hid_t dxpl_id, size_t init, H5G_entry_t *self/*out*/)
+H5G_stab_create_components(H5F_t *f, H5O_stab_t *stab, size_t size_hint, hid_t dxpl_id)
 {
-    size_t		    name;	/*offset of "" name	*/
-    H5O_stab_t		    stab;	/*symbol table message	*/
-    herr_t      ret_value=SUCCEED;       /* Return value */
+    size_t	name_offset;	        /* Offset of "" name	*/
+    herr_t      ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI(H5G_stab_create, FAIL)
+    FUNC_ENTER_NOAPI(H5G_stab_create_components, FAIL)
 
     /*
      * Check arguments.
      */
     HDassert(f);
-    HDassert(self);
-    init = MAX(init, H5HL_SIZEOF_FREE(f) + 2);
+    HDassert(stab);
+    HDassert(size_hint > 0);
+
+    /* Create the B-tree */
+    if(H5B_create(f, dxpl_id, H5B_SNODE, NULL, &(stab->btree_addr)/*out*/) < 0)
+	HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create B-tree")
 
     /* Create symbol table private heap */
-    if (H5HL_create(f, dxpl_id, init, &(stab.heap_addr)/*out*/)<0)
+    if(H5HL_create(f, dxpl_id, size_hint, &(stab->heap_addr)/*out*/) < 0)
 	HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create heap")
-    name = H5HL_insert(f, dxpl_id, stab.heap_addr, 1, "");
-    if ((size_t)(-1)==name)
+    name_offset = H5HL_insert(f, dxpl_id, stab->heap_addr, 1, "");
+    if((size_t)(-1) == name_offset)
 	HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't initialize heap")
 
     /*
      * B-tree's won't work if the first name isn't at the beginning
      * of the heap.
      */
-    assert(0 == name);
+    HDassert(0 == name_offset);
 
-    /* Create the B-tree */
-    if (H5B_create(f, dxpl_id, H5B_SNODE, NULL, &(stab.btree_addr)/*out*/) < 0)
-	HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create B-tree")
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_stab_create_components() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_stab_create
+ *
+ * Purpose:	Creates a new empty symbol table (object header, name heap,
+ *		and B-tree).  The caller can specify an initial size for the
+ *		name heap.  The object header of the group is opened for
+ *		write access.
+ *
+ *		In order for the B-tree to operate correctly, the first
+ *		item in the heap is the empty string, and must appear at
+ *		heap offset zero.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Robb Matzke
+ *		matzke@llnl.gov
+ *		Aug  1 1997
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5G_stab_create(H5O_loc_t *grp_oloc, H5O_stab_t *stab, hid_t dxpl_id)
+{
+    H5O_ginfo_t	ginfo;	                /* Group info message   */
+    size_t      heap_hint;              /* Local heap size hint */
+    size_t      size_hint;              /* Local heap size hint */
+    herr_t      ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_NOAPI(H5G_stab_create, FAIL)
 
     /*
-     * Create symbol table object header.  It has a zero link count
-     * since nothing refers to it yet.	The link count will be
-     * incremented if the object is added to the group directed graph.
+     * Check arguments.
      */
-    if (H5O_create(f, dxpl_id, 4 + 2 * H5F_SIZEOF_ADDR(f), self/*out*/) < 0)
-	HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create header")
+    HDassert(grp_oloc);
+    HDassert(stab);
+
+    /* Get the group info */
+    if(NULL == H5O_read(grp_oloc, H5O_GINFO_ID, 0, &ginfo, dxpl_id))
+	HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "can't get group info")
+
+    /* Adjust the size hint, if necessary */
+    if(ginfo.lheap_size_hint == 0)
+        heap_hint = ginfo.est_num_entries * (ginfo.est_name_len + 1);
+    else
+        heap_hint = ginfo.lheap_size_hint;
+    size_hint = MAX(heap_hint, H5HL_SIZEOF_FREE(grp_oloc->file) + 2);
+
+    if(H5G_stab_create_components(grp_oloc->file, stab, size_hint, dxpl_id) < 0)
+	HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create symbol table components")
 
     /*
      * Insert the symbol table message into the object header and the symbol
      * table entry.
      */
-    if (H5O_modify(self, H5O_STAB_ID, H5O_NEW_MESG, H5O_FLAG_CONSTANT, H5O_UPDATE_TIME, &stab, dxpl_id)<0) {
-	H5O_close(self);
+    if(H5O_modify(grp_oloc, H5O_STAB_ID, H5O_NEW_MESG, 0, H5O_UPDATE_TIME, stab, dxpl_id) < 0)
 	HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create message")
-    }
-    self->cache.stab.btree_addr = stab.btree_addr;
-    self->cache.stab.heap_addr = stab.heap_addr;
-    self->type = H5G_CACHED_STAB;
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
@@ -114,62 +197,47 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5G_stab_find
- *
- * Purpose:	Finds a symbol named NAME in the symbol table whose
- *		description is stored in GRP_ENT in file F and returns its
- *		symbol table entry through OBJ_ENT (which is optional).
+ * Function:	H5G_stab_insert_real
  *
- * Errors:
+ * Purpose:	Insert a new symbol into a table.
+ *		The name of the new symbol is NAME and its symbol
+ *		table entry is OBJ_LNK.
  *
  * Return:	Non-negative on success/Negative on failure
  *
- * Programmer:	Robb Matzke
- *		matzke@llnl.gov
- *		Aug  1 1997
- *
- * Modifications:
- *
- *      Pedro Vicente, <pvn@ncsa.uiuc.edu> 22 Aug 2002
- *      Added `id to name' support.
- *      Added a deep copy of the symbol table entry
+ * Programmer:	Quincey Koziol
+ *		koziol@uiuc.edu
+ *		Nov  7 2005
  *
  *-------------------------------------------------------------------------
  */
 herr_t
-H5G_stab_find(H5G_entry_t *grp_ent, const char *name,
-	      H5G_entry_t *obj_ent/*out*/, hid_t dxpl_id)
+H5G_stab_insert_real(H5F_t *f, H5O_stab_t *stab, const char *name,
+    H5O_link_t *obj_lnk, hid_t dxpl_id)
 {
-    H5G_bt_ud1_t	udata;		/*data to pass through B-tree	*/
-    H5O_stab_t		stab;		/*symbol table message		*/
-    herr_t      ret_value=SUCCEED;       /* Return value */
+    H5G_bt_ud1_t	udata;		/* Data to pass through B-tree	*/
+    herr_t              ret_value = SUCCEED;       /* Return value */
 
-    FUNC_ENTER_NOAPI(H5G_stab_find, FAIL)
+    FUNC_ENTER_NOAPI(H5G_stab_insert_real, FAIL)
 
-    /* Check arguments */
-    assert(grp_ent);
-    assert(grp_ent->file);
-    assert(obj_ent);
-    assert(name && *name);
+    /* check arguments */
+    HDassert(f);
+    HDassert(stab);
+    HDassert(name && *name);
+    HDassert(obj_lnk);
 
-    /* set up the udata */
-    if (NULL == H5O_read(grp_ent, H5O_STAB_ID, 0, &stab, dxpl_id))
-	HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "can't read message")
+    /* Initialize data to pass through B-tree */
     udata.common.name = name;
-    udata.common.heap_addr = stab.heap_addr;
-    udata.ent = obj_ent;
-
-    /* search the B-tree */
-    if (H5B_find(grp_ent->file, dxpl_id, H5B_SNODE, stab.btree_addr, &udata) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "not found")
+    udata.common.heap_addr = stab->heap_addr;
+    udata.lnk = obj_lnk;
 
-    /* Set the name for the symbol entry OBJ_ENT */
-    if (H5G_ent_set_name( grp_ent, obj_ent, name ) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "cannot insert name")
+    /* Insert into symbol table */
+    if(H5B_insert(f, dxpl_id, H5B_SNODE, stab->btree_addr, &udata) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTINSERT, FAIL, "unable to insert entry")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_stab_find() */
+} /* end H5G_stab_insert_real() */
 
 
 /*-------------------------------------------------------------------------
@@ -188,46 +256,29 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5G_stab_insert(H5G_entry_t *grp_ent, const char *name, H5G_entry_t *obj_ent,
-    hbool_t inc_link, hid_t dxpl_id)
+H5G_stab_insert(H5O_loc_t *grp_oloc, const char *name, H5O_link_t *obj_lnk,
+    hid_t dxpl_id)
 {
-    H5O_stab_t		stab;		/*symbol table message		*/
-    H5G_bt_ud1_t	udata;		/*data to pass through B-tree	*/
-    herr_t      ret_value=SUCCEED;       /* Return value */
+    H5O_stab_t		stab;		/* Symbol table message		*/
+    herr_t              ret_value = SUCCEED;       /* Return value */
 
     FUNC_ENTER_NOAPI(H5G_stab_insert, FAIL)
 
     /* check arguments */
-    assert(grp_ent && grp_ent->file);
-    assert(name && *name);
-    assert(obj_ent && obj_ent->file);
-    if (grp_ent->file->shared != obj_ent->file->shared)
-	HGOTO_ERROR(H5E_SYM, H5E_LINK, FAIL, "interfile hard links are not allowed")
-
-    /* Set the name for the symbol entry OBJ_ENT */
-    if (H5G_ent_set_name( grp_ent, obj_ent, name ) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "cannot insert name")
+    HDassert(grp_oloc && grp_oloc->file);
+    HDassert(name && *name);
+    HDassert(obj_lnk);
 
-    /* initialize data to pass through B-tree */
-    if (NULL == H5O_read(grp_ent, H5O_STAB_ID, 0, &stab, dxpl_id))
-	HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "not a symbol table")
+    /* Retrieve symbol table message */
+    if(NULL == H5O_read(grp_oloc, H5O_STAB_ID, 0, &stab, dxpl_id))
+        HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "not a symbol table")
 
-    udata.common.name = name;
-    udata.common.heap_addr = stab.heap_addr;
-    udata.ent = obj_ent;
-
-    /* insert */
-    if (H5B_insert(grp_ent->file, dxpl_id, H5B_SNODE, stab.btree_addr, &udata) < 0)
-	HGOTO_ERROR(H5E_SYM, H5E_CANTINSERT, FAIL, "unable to insert entry")
-
-    /* Increment link count on object, if appropriate */
-    if(inc_link)
-        if (H5O_link(obj_ent, 1, dxpl_id) < 0)
-            HGOTO_ERROR(H5E_SYM, H5E_LINK, FAIL, "unable to increment hard link count")
+    if(H5G_stab_insert_real(grp_oloc->file, &stab, name, obj_lnk, dxpl_id) < 0)
+        HGOTO_ERROR(H5E_DATATYPE, H5E_CANTINIT, H5B_ITER_ERROR, "unable to insert the name")
 
 done:
-    FUNC_LEAVE_NOAPI(ret_value);
-}
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_stab_insert() */
 
 
 /*-------------------------------------------------------------------------
@@ -240,36 +291,37 @@ done:
  * Programmer:	Robb Matzke
  *              Thursday, September 17, 1998
  *
- * Modifications:
- *
  *-------------------------------------------------------------------------
  */
 herr_t
-H5G_stab_remove(H5G_entry_t *grp_ent, const char *name, hid_t dxpl_id)
+H5G_stab_remove(H5O_loc_t *loc, const char *name, H5G_obj_t *obj_type, hid_t dxpl_id)
 {
     H5O_stab_t		stab;		/*symbol table message		*/
     H5G_bt_ud2_t	udata;		/*data to pass through B-tree	*/
-    herr_t      ret_value=SUCCEED;       /* Return value */
+    herr_t              ret_value = SUCCEED;       /* Return value */
 
     FUNC_ENTER_NOAPI(H5G_stab_remove, FAIL)
 
-    assert(grp_ent && grp_ent->file);
-    assert(name && *name);
+    HDassert(loc && loc->file);
+    HDassert(name && *name);
 
-    /* initialize data to pass through B-tree */
-    if (NULL==H5O_read(grp_ent, H5O_STAB_ID, 0, &stab, dxpl_id))
-	HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "not a symbol table")
+    /* Read in symbol table message */
+    if(NULL == H5O_read(loc, H5O_STAB_ID, 0, &stab, dxpl_id))
+        HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "not a symbol table")
+
+    /* Initialize data to pass through B-tree */
     udata.common.name = name;
     udata.common.heap_addr = stab.heap_addr;
     udata.adj_link = TRUE;
+    udata.obj_type = obj_type;
 
-    /* remove */
-    if (H5B_remove(grp_ent->file, dxpl_id, H5B_SNODE, stab.btree_addr, &udata)<0)
-	HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "unable to remove entry")
+    /* Remove from symbol table */
+    if(H5B_remove(loc->file, dxpl_id, H5B_SNODE, stab.btree_addr, &udata) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "unable to remove entry")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-}
+} /* end H5G_stab_remove() */
 
 
 /*-------------------------------------------------------------------------
@@ -318,47 +370,324 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:    H5G_stab_copy_tmp
+ * Function:	H5G_stab_iterate
+ *
+ * Purpose:	Iterate over the objects in a group
  *
- * Purpose:     copy a group symbol table and memeber objects from SRC file to DST file.
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, October  3, 2005
  *
- * Return:      Non-negative on success
- *              Negative on failure.
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5G_stab_iterate(H5O_loc_t *oloc, hid_t gid, int skip, int *last_obj,
+    H5G_iterate_t op, void *op_data, hid_t dxpl_id)
+{
+    H5G_bt_it_ud1_t	udata;                  /* User data to pass to B-tree callback */
+    H5O_stab_t		stab;		        /* Info about symbol table */
+    herr_t		ret_value;
+
+    FUNC_ENTER_NOAPI(H5G_stab_iterate, FAIL)
+
+    /* Sanity check */
+    HDassert(oloc);
+    HDassert(H5I_GROUP == H5I_get_type(gid));
+    HDassert(last_obj);
+    HDassert(op);
+
+    /* Get the B-tree info */
+    if(NULL == H5O_read(oloc, H5O_STAB_ID, 0, &stab, dxpl_id))
+	HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "unable to determine local heap address")
+
+    /* Build udata to pass through H5B_iterate() to H5G_node_iterate() */
+    udata.group_id = gid;
+    udata.skip = skip;
+    udata.heap_addr = stab.heap_addr;
+    udata.op = op;
+    udata.op_data = op_data;
+    udata.final_ent = last_obj;
+
+    /* Iterate over the group members */
+    if((ret_value = H5B_iterate(oloc->file, H5AC_dxpl_id, H5B_SNODE,
+              H5G_node_iterate, stab.btree_addr, &udata))<0)
+        HERROR(H5E_SYM, H5E_CANTNEXT, "iteration operator failed");
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_stab_iterate() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_stab_count
  *
- * Programmer:  Peter Cao       
- *              September 10, 2005 
+ * Purpose:	Count the # of objects in a group
  *
- * Note:        This routine should be replaced with proper call to "real"
- *              stab creation routine after the "big group revision" checkin
- *              occurs. -QAK
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, September  6, 2005
  *
  *-------------------------------------------------------------------------
  */
 herr_t
-H5G_stab_copy_tmp(H5F_t *f_dst,  H5O_stab_t *stab_dst, hid_t dxpl_id)
+H5G_stab_count(H5O_loc_t *oloc, hsize_t *num_objs, hid_t dxpl_id)
+{
+    H5O_stab_t		stab;		        /* Info about symbol table */
+    herr_t		ret_value;
+
+    FUNC_ENTER_NOAPI(H5G_stab_count, FAIL)
+
+    /* Sanity check */
+    HDassert(oloc);
+    HDassert(num_objs);
+
+    /* Reset the number of objects in the group */
+    *num_objs = 0;
+
+    /* Get the B-tree info */
+    if(NULL == H5O_read(oloc, H5O_STAB_ID, 0, &stab, dxpl_id))
+	HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "unable to determine local heap address")
+
+    /* Iterate over the group members */
+    if((ret_value = H5B_iterate(oloc->file, dxpl_id, H5B_SNODE, H5G_node_sumup, stab.btree_addr, num_objs)) < 0)
+        HERROR(H5E_SYM, H5E_CANTINIT, "iteration operator failed");
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_stab_count() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_stab_get_name_by_idx
+ *
+ * Purpose:     Returns the name of objects in the group by giving index.
+ *
+ * Return:	Success:        Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Raymond Lu
+ *	        Nov 20, 2002
+ *
+ *-------------------------------------------------------------------------
+ */
+ssize_t
+H5G_stab_get_name_by_idx(H5O_loc_t *oloc, hsize_t idx, char* name,
+    size_t size, hid_t dxpl_id)
+{
+    H5O_stab_t		stab;	        /* Info about local heap & B-tree */
+    H5G_bt_it_ud2_t	udata;          /* Iteration information */
+    ssize_t		ret_value;      /* Return value */
+
+    FUNC_ENTER_NOAPI(H5G_stab_get_name_by_idx, FAIL)
+
+    /* Sanity check */
+    HDassert(oloc);
+
+    /* Get the B-tree & local heap info */
+    if(NULL == H5O_read(oloc, H5O_STAB_ID, 0, &stab, dxpl_id))
+	HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "unable to determine local heap address")
+
+    /* Set iteration information */
+    udata.idx = idx;
+    udata.num_objs = 0;
+    udata.heap_addr = stab.heap_addr;
+    udata.name = NULL;
+
+    /* Iterate over the group members */
+    if((ret_value = H5B_iterate(oloc->file, dxpl_id, H5B_SNODE, H5G_node_name, stab.btree_addr, &udata))<0)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "iteration operator failed")
+
+    /* If we don't know the name now, we almost certainly went out of bounds */
+    if(udata.name==NULL)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "index out of bound")
+
+    /* Get the length of the name */
+    ret_value = (ssize_t)HDstrlen(udata.name);
+
+    /* Copy the name into the user's buffer, if given */
+    if(name) {
+        HDstrncpy(name, udata.name, MIN((size_t)(ret_value+1),size));
+        if((size_t)ret_value >= size)
+            name[size-1]='\0';
+    } /* end if */
+
+done:
+    /* Free the duplicated name */
+    if(udata.name!=NULL)
+        H5MM_xfree(udata.name);
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_stab_get_name_by_idx() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_get_objtype_by_idx
+ *
+ * Purpose:     Private function for H5Gget_objtype_by_idx.
+ *              Returns the type of objects in the group by giving index.
+ *
+ * Return:	Success:        H5G_GROUP(1), H5G_DATASET(2), H5G_TYPE(3)
+ *
+ *		Failure:	UNKNOWN
+ *
+ * Programmer:	Raymond Lu
+ *	        Nov 20, 2002
+ *
+ *-------------------------------------------------------------------------
+ */
+H5G_obj_t
+H5G_stab_get_type_by_idx(H5O_loc_t *oloc, hsize_t idx, hid_t dxpl_id)
+{
+    H5O_stab_t		stab;	        /* Info about local heap & B-tree */
+    H5G_bt_it_ud3_t	udata;          /* User data for B-tree callback */
+    H5G_obj_t		ret_value;      /* Return value */
+
+    FUNC_ENTER_NOAPI(H5G_stab_get_type_by_idx, H5G_UNKNOWN)
+
+    /* Sanity check */
+    HDassert(oloc);
+
+    /* Get the B-tree & local heap info */
+    if(NULL == H5O_read(oloc, H5O_STAB_ID, 0, &stab, dxpl_id))
+	HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, H5G_UNKNOWN, "unable to determine local heap address")
+
+    /* Set iteration information */
+    udata.idx = idx;
+    udata.num_objs = 0;
+    udata.type = H5G_UNKNOWN;
+
+    /* Iterate over the group members */
+    if(H5B_iterate(oloc->file, dxpl_id, H5B_SNODE, H5G_node_type, stab.btree_addr, &udata) < 0)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5G_UNKNOWN, "iteration operator failed")
+
+    /* If we don't know the type now, we almost certainly went out of bounds */
+    if(udata.type == H5G_UNKNOWN)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, H5G_UNKNOWN, "index out of bound")
+
+    /* Set the return value */
+    ret_value = udata.type;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_stab_get_type_by_idx() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_stab_lookup_cb
+ *
+ * Purpose:     B-tree 'find' callback to retrieve location for an object
+ *
+ * Return:	Success:        Non-negative
+ *
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *	        Sep 20, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5G_stab_lookup_cb(const H5G_entry_t *ent, void *_udata)
 {
-    size_t      size_init, name_offset;
-    herr_t      ret_value = SUCCEED;       /* Return value */
+    H5G_stab_fnd_ud2_t *udata = (H5G_stab_fnd_ud2_t *)_udata;   /* 'User data' passed in */
+    herr_t ret_value = SUCCEED; /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5G_stab_lookup_cb)
+
+    /* Set link info */
+    if(udata->lnk) {
+        /* Set (default) common info for link */
+        udata->lnk->cset = H5T_CSET_ASCII;
+        udata->lnk->ctime = 0;
+        udata->lnk->name = H5MM_xstrdup(udata->name);
+
+        /* Object is a symbolic link */
+        if(H5G_CACHED_SLINK == ent->type) {
+            const char *s;          /* Pointer to link value */
+            const H5HL_t *heap;     /* Pointer to local heap for group */
+
+            /* Lock the local heap */
+            if(NULL == (heap = H5HL_protect(udata->file, udata->dxpl_id, udata->heap_addr)))
+                HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "unable to read protect link value")
 
-    FUNC_ENTER_NOAPI(H5G_stab_copy_tmp, FAIL)
+            s = H5HL_offset_into(udata->file, heap, ent->cache.slink.lval_offset);
 
-    HDassert(f_dst);
-    HDassert(stab_dst);
+            /* Copy the link value */
+            udata->lnk->u.soft.name = H5MM_xstrdup(s);
 
-   /* create B-tree private heap */
-   size_init = MAX(H5G_SIZE_HINT, H5HL_SIZEOF_FREE(f_dst) + 2);
-   if (H5HL_create(f_dst, dxpl_id, size_init, &(stab_dst->heap_addr))<0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create heap")
+            /* Release the local heap */
+            if(H5HL_unprotect(udata->file, udata->dxpl_id, heap, udata->heap_addr, H5AC__NO_FLAGS_SET) < 0)
+                HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "unable to read unprotect link value")
 
-    name_offset = H5HL_insert(f_dst, dxpl_id, stab_dst->heap_addr, 1, "");
-    if ((size_t)(-1)==name_offset)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't initialize heap")
-    assert(0 == name_offset);
-  
-    /* create the B-tree */
-    if (H5B_create(f_dst, dxpl_id, H5B_SNODE, NULL, &(stab_dst->btree_addr)) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create B-tree")
+            /* Set link type */
+            udata->lnk->type = H5G_LINK_SOFT;
+        } /* end if */
+        else {
+            /* Set address of object */
+            udata->lnk->u.hard.addr = ent->header;
+
+            /* Set link type */
+            udata->lnk->type = H5G_LINK_HARD;
+        } /* end else */
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_stab_lookup_cb() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_stab_lookup
+ *
+ * Purpose:	Look up an object relative to a group, using symbol table
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Sep 20 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5G_stab_lookup(H5O_loc_t *grp_oloc, const char *name, H5O_link_t *lnk,
+    hid_t dxpl_id)
+{
+    H5G_bt_ud3_t bt_udata;      /* Data to pass through B-tree	*/
+    H5G_stab_fnd_ud2_t udata;   /* 'User data' to give to callback */
+    H5O_stab_t stab;		/* Symbol table message		*/
+    herr_t     ret_value = SUCCEED;     /* Return value */
+
+    FUNC_ENTER_NOAPI(H5G_stab_lookup, FAIL)
+
+    /* check arguments */
+    HDassert(grp_oloc && grp_oloc->file);
+    HDassert(name && *name);
+    HDassert(lnk);
+
+    /* Set up user data to pass to 'find' operation callback */
+    udata.file = grp_oloc->file;
+    udata.dxpl_id = dxpl_id;
+    udata.name = name;
+    udata.lnk = lnk;
+
+    /* Set up the user data for actual B-tree find operation */
+    if(NULL == H5O_read(grp_oloc, H5O_STAB_ID, 0, &stab, dxpl_id))
+        HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "can't read message")
+    bt_udata.common.name = name;
+    bt_udata.common.heap_addr = stab.heap_addr;
+    bt_udata.op = H5G_stab_lookup_cb;
+    bt_udata.op_data = &udata;
+
+    /* Finish up user data to pass to 'find' operation callback */
+    udata.heap_addr = stab.heap_addr;
+
+    /* Search the B-tree */
+    if(H5B_find(grp_oloc->file, dxpl_id, H5B_SNODE, stab.btree_addr, &bt_udata) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "not found")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_stab_copy_tmp() */
+} /* end H5G_stab_lookup() */
+