[svn-r12896] Description:

    Move compact storage routines into separate file, to make room for internal
routines that operate on links within group operations.

Tested on:
    Linux/32 2.6 (chicago)

10 files changed, 879 insertions, 801 deletions

diff --git a/MANIFEST b/MANIFEST
index ffb8f20..40776fe 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -502,6 +502,7 @@
 ./src/H5FSsection.c
 ./src/H5G.c
 ./src/H5Gbtree2.c
+./src/H5Gcompact.c
 ./src/H5Gdense.c
 ./src/H5Gdeprec.c
 ./src/H5Gent.c
diff --git a/src/H5Gbtree2.c b/src/H5Gbtree2.c
index bc53998..8b0aa11 100644
--- a/src/H5Gbtree2.c
+++ b/src/H5Gbtree2.c
@@ -101,7 +101,6 @@ static herr_t H5G_dense_btree2_name_debug(FILE *stream, const H5F_t *f, hid_t dx
 static herr_t H5G_dense_fh_name_cmp(const void *obj, size_t obj_len, void *op_data);
 
 
-
 /*********************/
 /* Package Variables */
 /*********************/
@@ -138,6 +137,7 @@ const H5B2_class_t H5G_BT2_CORDER[1]={{ /* B-tree class information */
 /* Local Variables */
 /*******************/
 
+
 
 /*-------------------------------------------------------------------------
  * Function:	H5G_dense_fh_name_cmp
diff --git a/src/H5Gcompact.c b/src/H5Gcompact.c
new file mode 100644
index 0000000..50e661b
--- /dev/null
+++ b/src/H5Gcompact.c
@@ -0,0 +1,668 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * All rights reserved.                                                      *
+ *                                                                           *
+ * This file is part of HDF5.  The full HDF5 copyright notice, including     *
+ * terms governing use, modification, and redistribution, is contained in    *
+ * the files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
+ * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*-------------------------------------------------------------------------
+ *
+ * Created:		H5Gcompact.c
+ *			Sep  5 2005
+ *			Quincey Koziol <koziol@ncsa.uiuc.edu>
+ *
+ * Purpose:		Functions for handling compact storage.
+ *
+ *-------------------------------------------------------------------------
+ */
+#define H5G_PACKAGE		/*suppress error about including H5Gpkg	  */
+
+
+/* Packages needed by this file... */
+#include "H5private.h"		/* Generic Functions			*/
+#include "H5Eprivate.h"		/* Error handling		  	*/
+#include "H5Gpkg.h"		/* Groups		  		*/
+#include "H5Iprivate.h"		/* IDs			  		*/
+#include "H5MMprivate.h"	/* Memory management			*/
+
+/* Private typedefs */
+
+/* User data for link message iteration when building link table */
+typedef struct {
+    H5G_link_table_t *ltable;   /* Pointer to link table to build */
+    size_t curr_lnk;            /* Current link to operate on */
+} H5G_compact_ud1_t;
+
+/* User data for deleting a link in the link messages */
+typedef struct {
+    /* downward */
+    const char *name;           /* Name to search for */
+    H5F_t       *file;          /* File that object header is located within */
+    hid_t       dxpl_id;        /* DXPL during insertion */
+
+    /* upward */
+    H5G_obj_t *obj_type;        /* Type of object deleted */
+} H5G_compact_ud2_t;
+
+/* User data for link message iteration when querying object info */
+typedef struct {
+    /* downward */
+    const char *name;           /* Name to search for */
+    H5F_t       *file;          /* File that object header is located within */
+    hid_t       dxpl_id;        /* DXPL during insertion */
+
+    /* upward */
+    H5G_stat_t *statbuf;        /* Stat buffer for info */
+} H5G_compact_ud3_t;
+
+/* User data for link message iteration when querying object location */
+typedef struct {
+    /* downward */
+    const char *name;           /* Name to search for */
+
+    /* upward */
+    H5O_link_t *lnk;            /* Link struct to fill in */
+    hbool_t found;              /* Flag to indicate that the object was found */
+} H5G_compact_ud4_t;
+
+/* User data for link message iteration when querying soft link value */
+typedef struct {
+    /* downward */
+    const char *name;           /* Name to search for */
+    size_t size;                /* Buffer size for link value */
+
+    /* upward */
+    char *buf;                  /* Buffer to fill with link value */
+} H5G_compact_ud5_t;
+
+/* Private macros */
+
+/* PRIVATE PROTOTYPES */
+static herr_t H5G_compact_build_table_cb(const void *_mesg, unsigned idx, void *_udata);
+static herr_t H5G_compact_build_table(H5O_loc_t *oloc, hid_t dxpl_id,
+    const H5O_linfo_t *linfo, H5L_index_t idx_type, H5_iter_order_t order,
+    H5G_link_table_t *ltable);
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_compact_build_table_cb
+ *
+ * Purpose:	Callback routine for searching 'link' messages for a particular
+ *              name.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Sep  5 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5G_compact_build_table_cb(const void *_mesg, unsigned UNUSED idx, void *_udata)
+{
+    const H5O_link_t *lnk = (const H5O_link_t *)_mesg;  /* Pointer to link */
+    H5G_compact_ud1_t *udata = (H5G_compact_ud1_t *)_udata;     /* 'User data' passed in */
+    herr_t ret_value=H5O_ITER_CONT;             /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5G_compact_build_table_cb)
+
+    /* check arguments */
+    HDassert(lnk);
+    HDassert(udata);
+    HDassert(udata->curr_lnk < udata->ltable->nlinks);
+
+    /* Copy link message into table */
+    if(NULL == H5O_copy(H5O_LINK_ID, lnk, &(udata->ltable->lnks[udata->curr_lnk])))
+        HGOTO_ERROR(H5E_SYM, H5E_CANTCOPY, H5O_ITER_ERROR, "can't copy link message")
+
+    /* Increment current link entry to operate on */
+    udata->curr_lnk++;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_compact_build_table_cb() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_compact_build_table
+ *
+ * Purpose:     Builds a table containing a sorted (alphabetically) list of
+ *              links for a group
+ *
+ * Return:	Success:        Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *	        Sep  6, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5G_compact_build_table(H5O_loc_t *oloc, hid_t dxpl_id, const H5O_linfo_t *linfo,
+    H5L_index_t idx_type, H5_iter_order_t order, H5G_link_table_t *ltable)
+{
+    herr_t	ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5G_compact_build_table)
+
+    /* Sanity check */
+    HDassert(oloc);
+    HDassert(linfo);
+    HDassert(ltable);
+
+    /* Set size of table */
+    H5_CHECK_OVERFLOW(linfo->nlinks, hsize_t, size_t);
+    ltable->nlinks = (size_t)linfo->nlinks;
+
+    /* Allocate space for the table entries */
+    if(ltable->nlinks > 0) {
+        H5G_compact_ud1_t udata;               /* User data for iteration callback */
+
+        if((ltable->lnks = H5MM_malloc(sizeof(H5O_link_t) * ltable->nlinks)) == NULL)
+            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
+
+        /* Set up user data for iteration */
+        udata.ltable = ltable;
+        udata.curr_lnk = 0;
+
+        /* Iterate through the link messages, adding them to the table */
+        if(H5O_iterate(oloc, H5O_LINK_ID, H5G_compact_build_table_cb, &udata, dxpl_id) < 0)
+            HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "error iterating over link messages")
+
+        /* Sort link table in correct iteration order */
+        if(idx_type == H5L_INDEX_NAME) {
+            if(order == H5_ITER_INC)
+                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_link_cmp_name_inc);
+            else if(order == H5_ITER_DEC)
+                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_link_cmp_name_dec);
+            else
+                HDassert(order == H5_ITER_NATIVE);
+        } /* end if */
+        else {
+            HDassert(idx_type == H5L_INDEX_CRT_ORDER);
+            if(order == H5_ITER_INC)
+                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_link_cmp_corder_inc);
+            else if(order == H5_ITER_DEC)
+                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_link_cmp_corder_dec);
+            else
+                HDassert(order == H5_ITER_NATIVE);
+        } /* end else */
+    } /* end if */
+    else
+        ltable->lnks = NULL;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_compact_build_table() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_compact_insert
+ *
+ * Purpose:	Insert a new symbol into the table described by GRP_ENT in
+ *		file F.	 The name of the new symbol is NAME and its symbol
+ *		table entry is OBJ_ENT.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Sep  6 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5G_compact_insert(H5O_loc_t *grp_oloc, H5O_link_t *obj_lnk,
+    hid_t dxpl_id)
+{
+    herr_t     ret_value = SUCCEED;       /* Return value */
+
+    FUNC_ENTER_NOAPI(H5G_compact_insert, FAIL)
+
+    /* check arguments */
+    HDassert(grp_oloc && grp_oloc->file);
+    HDassert(obj_lnk);
+
+    /* Insert link message into group */
+    if(H5O_modify(grp_oloc, H5O_LINK_ID, H5O_NEW_MESG, 0, H5O_UPDATE_TIME, obj_lnk, dxpl_id) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create message")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_compact_insert() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_compact_get_name_by_idx
+ *
+ * Purpose:     Returns the name of objects in the group by giving index.
+ *
+ * Return:	Success:        Non-negative, length of name
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *	        Sep  6, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+ssize_t
+H5G_compact_get_name_by_idx(H5O_loc_t *oloc, hid_t dxpl_id,
+    const H5O_linfo_t *linfo, H5L_index_t idx_type, H5_iter_order_t order,
+    hsize_t idx, char* name, size_t size)
+{
+    H5G_link_table_t    ltable = {0, NULL};         /* Link table */
+    ssize_t		ret_value;      /* Return value */
+
+    FUNC_ENTER_NOAPI(H5G_compact_get_name_by_idx, FAIL)
+
+    /* Sanity check */
+    HDassert(oloc);
+
+    /* Build table of all link messages */
+    if(H5G_compact_build_table(oloc, dxpl_id, linfo, idx_type, order, &ltable) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create link message table")
+
+    /* Check for going out of bounds */
+    if(idx >= ltable.nlinks)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "index out of bound")
+
+    /* Get the length of the name */
+    ret_value = (ssize_t)HDstrlen(ltable.lnks[idx].name);
+
+    /* Copy the name into the user's buffer, if given */
+    if(name) {
+        HDstrncpy(name, ltable.lnks[idx].name, MIN((size_t)(ret_value + 1), size));
+        if((size_t)ret_value >= size)
+            name[size - 1]='\0';
+    } /* end if */
+
+done:
+    /* Release link table */
+    if(ltable.lnks)
+        /* Free link table information */
+        if(H5G_link_release_table(&ltable) < 0)
+            HDONE_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to release link table")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_compact_get_name_by_idx() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_compact_get_type_by_idx
+ *
+ * Purpose:     Returns the type of objects in the group by giving index.
+ *
+ * Return:	Success:        Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *	        Sep 12, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+H5G_obj_t
+H5G_compact_get_type_by_idx(H5O_loc_t *oloc, hid_t dxpl_id, const H5O_linfo_t *linfo,
+    hsize_t idx)
+{
+    H5G_link_table_t    ltable = {0, NULL};         /* Link table */
+    H5G_obj_t		ret_value;      /* Return value */
+
+    FUNC_ENTER_NOAPI(H5G_compact_get_type_by_idx, H5G_UNKNOWN)
+
+    /* Sanity check */
+    HDassert(oloc);
+
+    /* Build table of all link messages */
+    if(H5G_compact_build_table(oloc, dxpl_id, linfo, H5L_INDEX_NAME, H5_ITER_INC, &ltable) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, H5G_UNKNOWN, "can't create link message table")
+
+    /* Check for going out of bounds */
+    if(idx >= ltable.nlinks)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, H5G_UNKNOWN, "index out of bound")
+
+    /* Determine type of object */
+    if(ltable.lnks[idx].type == H5L_TYPE_SOFT)
+        ret_value = H5G_LINK;
+    else if(ltable.lnks[idx].type >= H5L_TYPE_UD_MIN)
+        ret_value = H5G_UDLINK;
+    else if(ltable.lnks[idx].type == H5L_TYPE_HARD){
+        H5O_loc_t tmp_oloc;             /* Temporary object location */
+
+        /* Build temporary object location */
+        tmp_oloc.file = oloc->file;
+        tmp_oloc.addr = ltable.lnks[idx].u.hard.addr;
+
+        /* Get the type of the object */
+        if((ret_value = H5O_obj_type(&tmp_oloc, dxpl_id)) == H5G_UNKNOWN)
+            HGOTO_ERROR(H5E_SYM, H5E_BADTYPE, H5G_UNKNOWN, "can't determine object type")
+    } else {
+        HGOTO_ERROR(H5E_SYM, H5E_BADTYPE, H5G_UNKNOWN, "unknown link type")
+    } /* end else */
+
+done:
+    /* Release link table */
+    if(ltable.lnks)
+        /* Free link table information */
+        if(H5G_link_release_table(&ltable) < 0)
+            HDONE_ERROR(H5E_SYM, H5E_CANTFREE, H5G_UNKNOWN, "unable to release link table")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_compact_get_type_by_idx() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_compact_remove_cb
+ *
+ * Purpose:	Callback routine for deleting 'link' message for a particular
+ *              name.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Sep  5 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5G_compact_remove_cb(const void *_mesg, unsigned UNUSED idx, void *_udata)
+{
+    const H5O_link_t *lnk = (const H5O_link_t *)_mesg;  /* Pointer to link */
+    H5G_compact_ud2_t *udata = (H5G_compact_ud2_t *)_udata;     /* 'User data' passed in */
+    herr_t ret_value = H5O_ITER_CONT;           /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5G_compact_remove_cb)
+
+    /* check arguments */
+    HDassert(lnk);
+    HDassert(udata);
+
+    /* If we've found the right link, get the object type */
+    if(HDstrcmp(lnk->name, udata->name) == 0) {
+        switch(lnk->type)
+        {
+            case H5L_TYPE_HARD:
+                {
+                    H5O_loc_t tmp_oloc;             /* Temporary object location */
+
+                    /* Build temporary object location */
+                    tmp_oloc.file = udata->file;
+                    tmp_oloc.addr = lnk->u.hard.addr;
+
+                    /* Get the type of the object */
+                    /* Note: no way to check for error :-( */
+                    *(udata->obj_type) = H5O_obj_type(&tmp_oloc, udata->dxpl_id);
+                }
+                break;
+
+            case H5L_TYPE_SOFT:
+                *(udata->obj_type) = H5G_LINK;
+                break;
+
+            default:  /* User-defined link */
+                if(lnk->type < H5L_TYPE_UD_MIN)
+                   HGOTO_ERROR(H5E_SYM, H5E_BADVALUE, FAIL, "unknown link type")
+
+                *(udata->obj_type) = H5G_UDLINK;
+        }
+        /* Stop the iteration, we found the correct link */
+        HGOTO_DONE(H5O_ITER_STOP)
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_compact_remove_cb() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_compact_remove
+ *
+ * Purpose:	Remove NAME from links.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, September 19, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5G_compact_remove(const H5O_loc_t *oloc, const char *name, H5G_obj_t *obj_type,
+    hid_t dxpl_id)
+{
+    H5G_compact_ud2_t udata;               /* Data to pass through OH iteration */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(H5G_compact_remove, FAIL)
+
+    HDassert(oloc && oloc->file);
+    HDassert(name && *name);
+
+    /* Initialize data to pass through object header iteration */
+    udata.name = name;
+    udata.file = oloc->file;
+    udata.dxpl_id = dxpl_id;
+    udata.obj_type = obj_type;
+
+    /* Iterate over the link messages to delete the right one */
+    if(H5O_remove_op(oloc, H5O_LINK_ID, H5O_FIRST, H5G_compact_remove_cb, &udata, TRUE, dxpl_id) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTDELETE, FAIL, "unable to delete link message")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_compact_remove() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_compact_iterate
+ *
+ * Purpose:	Iterate over the links in a group
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *              Monday, October  3, 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5G_compact_iterate(H5O_loc_t *oloc, hid_t dxpl_id, const H5O_linfo_t *linfo, 
+    H5_iter_order_t order, hid_t gid, hbool_t lib_internal, int skip,
+    int *last_obj, H5G_link_iterate_t op, void *op_data)
+{
+    H5G_link_table_t    ltable = {0, NULL};     /* Link table */
+    size_t              u;                      /* Local index variable */
+    herr_t		ret_value;
+
+    FUNC_ENTER_NOAPI(H5G_compact_iterate, FAIL)
+
+    /* Sanity check */
+    HDassert(oloc);
+    HDassert(lib_internal || H5I_GROUP == H5I_get_type(gid));
+    HDassert(op.lib_op);
+
+    /* Build table of all link messages */
+    if(H5G_compact_build_table(oloc, dxpl_id, linfo, H5L_INDEX_NAME, order, &ltable) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create link message table")
+
+    /* Iterate over link messages */
+    for(u = 0, ret_value = H5B_ITER_CONT; u < ltable.nlinks && !ret_value; u++) {
+        if(skip > 0)
+            --skip;
+        else {
+            /* Check for internal callback with link info */
+            if(lib_internal)
+                ret_value = (op.lib_op)(&(ltable.lnks[u]), op_data);
+            else
+                ret_value = (op.app_op)(gid, ltable.lnks[u].name, op_data);
+        } /* end else */
+
+        /* Increment the number of entries passed through */
+        /* (whether we skipped them or not) */
+        (*last_obj)++;
+    } /* end for */
+
+    /* Check for callback failure and pass along return value */
+    if(ret_value < 0)
+        HERROR(H5E_SYM, H5E_CANTNEXT, "iteration operator failed");
+
+done:
+    /* Release link table */
+    if(ltable.lnks)
+        /* Free link table information */
+        if(H5G_link_release_table(&ltable) < 0)
+            HDONE_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to release link table")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_compact_iterate() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_compact_lookup_cb
+ *
+ * Purpose:	Callback routine for searching 'link' messages for a particular
+ *              name & gettting object location for it
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Sep 20 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5G_compact_lookup_cb(const void *_mesg, unsigned UNUSED idx, void *_udata)
+{
+    const H5O_link_t *lnk = (const H5O_link_t *)_mesg;  /* Pointer to link */
+    H5G_compact_ud4_t *udata = (H5G_compact_ud4_t *)_udata;     /* 'User data' passed in */
+    herr_t ret_value = H5O_ITER_CONT;           /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5G_compact_lookup_cb)
+
+    /* check arguments */
+    HDassert(lnk);
+    HDassert(udata);
+
+    /* Check for name to get information */
+    if(HDstrcmp(lnk->name, udata->name) == 0) {
+        if(udata->lnk) {
+            /* Copy link information */
+            if(NULL == H5O_copy(H5O_LINK_ID, lnk, udata->lnk))
+                HGOTO_ERROR(H5E_SYM, H5E_CANTCOPY, H5O_ITER_ERROR, "can't copy link message")
+        } /* end if */
+
+        /* Indicate that the correct link was found */
+        udata->found = TRUE;
+
+        /* Stop iteration now */
+        HGOTO_DONE(H5O_ITER_STOP)
+    } /* end if */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_compact_lookup_cb() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_compact_lookup
+ *
+ * Purpose:	Look up an object relative to a group, using link messages.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Sep 20 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5G_compact_lookup(H5O_loc_t *oloc, const char *name, H5O_link_t *lnk,
+    hid_t dxpl_id)
+{
+    H5G_compact_ud4_t udata;               /* User data for iteration callback */
+    herr_t     ret_value = SUCCEED;     /* Return value */
+
+    FUNC_ENTER_NOAPI(H5G_compact_lookup, FAIL)
+
+    /* check arguments */
+    HDassert(lnk && oloc->file);
+    HDassert(name && *name);
+
+    /* Set up user data for iteration */
+    udata.name = name;
+    udata.lnk = lnk;
+    udata.found = FALSE;
+
+    /* Iterate through the link messages, adding them to the table */
+    if(H5O_iterate(oloc, H5O_LINK_ID, H5G_compact_lookup_cb, &udata, dxpl_id) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "error iterating over link messages")
+
+    /* Check if we found the link we were looking for */
+    if(!udata.found)
+        HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "object not found")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_compact_lookup() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_compact_lookup_by_idx
+ *
+ * Purpose:	Look up an object in a group using link messages,
+ *              according to the order of an index
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Nov  6 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5G_compact_lookup_by_idx(H5O_loc_t *oloc, hid_t dxpl_id, const H5O_linfo_t *linfo,
+    H5L_index_t idx_type, H5_iter_order_t order, hsize_t n, H5O_link_t *lnk)
+{
+    H5G_link_table_t    ltable = {0, NULL};     /* Link table */
+    herr_t     ret_value = SUCCEED;     /* Return value */
+
+    FUNC_ENTER_NOAPI(H5G_compact_lookup_by_idx, FAIL)
+
+    /* check arguments */
+    HDassert(oloc && oloc->file);
+    HDassert(linfo);
+    HDassert(lnk);
+
+    /* Build table of all link messages, sorted according to desired order */
+    if(H5G_compact_build_table(oloc, dxpl_id, linfo, idx_type, order, &ltable) < 0)
+        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create link message table")
+
+    /* Check for going out of bounds */
+    if(n >= ltable.nlinks)
+	HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL, "index out of bound")
+
+    /* Copy link information */
+    if(NULL == H5O_copy(H5O_LINK_ID, &ltable.lnks[n], lnk))
+        HGOTO_ERROR(H5E_SYM, H5E_CANTCOPY, H5O_ITER_ERROR, "can't copy link message")
+
+done:
+    /* Release link table */
+    if(ltable.lnks)
+        /* Free link table information */
+        if(H5G_link_release_table(&ltable) < 0)
+            HDONE_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to release link table")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_compact_lookup_by_idx() */
+
diff --git a/src/H5Gdense.c b/src/H5Gdense.c
index 9e45f6a..3b8be2f 100644
--- a/src/H5Gdense.c
+++ b/src/H5Gdense.c
@@ -704,7 +704,7 @@ H5G_dense_lookup_by_idx(H5F_t *f, hid_t dxpl_id, const H5O_linfo_t *linfo,
             HGOTO_ERROR(H5E_SYM, H5E_CANTCOPY, H5B2_ITER_ERROR, "can't copy link message")
 
         /* Free link table information */
-        if(H5G_obj_release_table(&ltable) < 0)
+        if(H5G_link_release_table(&ltable) < 0)
             HGOTO_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to release link table")
     } /* end else */
 
@@ -810,18 +810,18 @@ H5G_dense_build_table(H5F_t *f, hid_t dxpl_id, const H5O_linfo_t *linfo,
         /* Sort link table in correct iteration order */
         if(idx_type == H5L_INDEX_NAME) {
             if(order == H5_ITER_INC)
-                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_obj_cmp_name_inc);
+                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_link_cmp_name_inc);
             else if(order == H5_ITER_DEC)
-                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_obj_cmp_name_dec);
+                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_link_cmp_name_dec);
             else
                 HDassert(order == H5_ITER_NATIVE);
         } /* end if */
         else {
             HDassert(idx_type == H5L_INDEX_CRT_ORDER);
             if(order == H5_ITER_INC)
-                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_obj_cmp_corder_inc);
+                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_link_cmp_corder_inc);
             else if(order == H5_ITER_DEC)
-                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_obj_cmp_corder_dec);
+                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_link_cmp_corder_dec);
             else
                 HDassert(order == H5_ITER_NATIVE);
         } /* end else */
@@ -1021,7 +1021,7 @@ H5G_dense_iterate(H5F_t *f, hid_t dxpl_id, H5_iter_order_t order, hid_t gid,
             HERROR(H5E_SYM, H5E_CANTNEXT, "iteration operator failed");
 
         /* Free link table information */
-        if(H5G_obj_release_table(&ltable) < 0)
+        if(H5G_link_release_table(&ltable) < 0)
             HGOTO_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to release link table")
     } /* end else */
 
@@ -1230,7 +1230,7 @@ H5G_dense_get_name_by_idx(H5F_t *f, hid_t dxpl_id, H5O_linfo_t *linfo,
         } /* end if */
 
         /* Free link table information */
-        if(H5G_obj_release_table(&ltable) < 0)
+        if(H5G_link_release_table(&ltable) < 0)
             HGOTO_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to release link table")
     } /* end else */
 
@@ -1304,7 +1304,7 @@ H5G_dense_get_type_by_idx(H5F_t *f, hid_t dxpl_id, H5O_linfo_t *linfo,
 done:
     /* Release link table */
     if(ltable.lnks)
-        if(H5G_obj_release_table(&ltable) < 0)
+        if(H5G_link_release_table(&ltable) < 0)
             HDONE_ERROR(H5E_SYM, H5E_CANTFREE, H5G_UNKNOWN, "unable to release link table")
 
     FUNC_LEAVE_NOAPI(ret_value)
@@ -1531,6 +1531,9 @@ H5G_dense_delete(H5F_t *f, hid_t dxpl_id, H5O_linfo_t *linfo, hbool_t adj_link)
     HDassert(linfo);
 
     /* Check if we are to adjust the ref. count for all the links */
+    /* (we adjust the ref. count when deleting a group and we _don't_ adjust
+     *  the ref. count when transitioning back to compact storage)
+    */
     if(adj_link) {
         H5HF_t *fheap = NULL;               /* Fractal heap handle */
         H5G_bt2_ud_rem_t udata;          /* User data for v2 B-tree record removal */
@@ -1548,7 +1551,7 @@ H5G_dense_delete(H5F_t *f, hid_t dxpl_id, H5O_linfo_t *linfo, hbool_t adj_link)
         udata.common.found_op = NULL;
         udata.common.found_op_data = NULL;
         udata.adj_link = TRUE;
-        udata.rem_from_fheap = FALSE;
+        udata.rem_from_fheap = FALSE;           /* handled in "bulk" below by deleting entire heap */
         udata.rem_from_corder_index = FALSE;
         udata.obj_type = NULL;
 
diff --git a/src/H5Glink.c b/src/H5Glink.c
index 17b8f0a..0600e97 100644
--- a/src/H5Glink.c
+++ b/src/H5Glink.c
@@ -15,90 +15,77 @@
 /*-------------------------------------------------------------------------
  *
  * Created:		H5Glink.c
- *			Sep  5 2005
- *			Quincey Koziol <koziol@ncsa.uiuc.edu>
+ *			Nov 13 2006
+ *			Quincey Koziol <koziol@hdfgroup.org>
  *
- * Purpose:		Functions for handling link messages.
+ * Purpose:		Functions for handling links in groups.
  *
  *-------------------------------------------------------------------------
  */
+
+/****************/
+/* Module Setup */
+/****************/
+
 #define H5G_PACKAGE		/*suppress error about including H5Gpkg	  */
 
 
-/* Packages needed by this file... */
+/***********/
+/* Headers */
+/***********/
 #include "H5private.h"		/* Generic Functions			*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5Gpkg.h"		/* Groups		  		*/
 #include "H5HLprivate.h"	/* Local Heaps				*/
-#include "H5Iprivate.h"		/* IDs			  		*/
-#include "H5MMprivate.h"	/* Memory management			*/
-
-/* Private typedefs */
-
-/* User data for link message iteration when building link table */
-typedef struct {
-    H5G_link_table_t *ltable;   /* Pointer to link table to build */
-    size_t curr_lnk;            /* Current link to operate on */
-} H5G_link_ud1_t;
-
-/* User data for deleting a link in the link messages */
-typedef struct {
-    /* downward */
-    const char *name;           /* Name to search for */
-    H5F_t       *file;          /* File that object header is located within */
-    hid_t       dxpl_id;        /* DXPL during insertion */
-
-    /* upward */
-    H5G_obj_t *obj_type;        /* Type of object deleted */
-} H5G_link_ud2_t;
-
-/* User data for link message iteration when querying object info */
-typedef struct {
-    /* downward */
-    const char *name;           /* Name to search for */
-    H5F_t       *file;          /* File that object header is located within */
-    hid_t       dxpl_id;        /* DXPL during insertion */
-
-    /* upward */
-    H5G_stat_t *statbuf;        /* Stat buffer for info */
-} H5G_link_ud3_t;
-
-/* User data for link message iteration when querying object location */
-typedef struct {
-    /* downward */
-    const char *name;           /* Name to search for */
-
-    /* upward */
-    H5O_link_t *lnk;            /* Link struct to fill in */
-    hbool_t found;              /* Flag to indicate that the object was found */
-} H5G_link_ud4_t;
-
-/* User data for link message iteration when querying soft link value */
-typedef struct {
-    /* downward */
-    const char *name;           /* Name to search for */
-    size_t size;                /* Buffer size for link value */
-
-    /* upward */
-    char *buf;                  /* Buffer to fill with link value */
-} H5G_link_ud5_t;
-
-/* Private macros */
-
-/* PRIVATE PROTOTYPES */
-static herr_t H5G_link_build_table_cb(const void *_mesg, unsigned idx, void *_udata);
-static herr_t H5G_link_build_table(H5O_loc_t *oloc, hid_t dxpl_id,
-    const H5O_linfo_t *linfo, H5L_index_t idx_type, H5_iter_order_t order,
-    H5G_link_table_t *ltable);
+
+
+/****************/
+/* Local Macros */
+/****************/
+
+
+/******************/
+/* Local Typedefs */
+/******************/
+
+
+/********************/
+/* Package Typedefs */
+/********************/
+
+
+/********************/
+/* Local Prototypes */
+/********************/
+
+
+/*********************/
+/* Package Variables */
+/*********************/
+
+
+/*****************************/
+/* Library Private Variables */
+/*****************************/
+
+
+/*******************/
+/* Local Variables */
+/*******************/
+
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5G_link_build_table_cb
+ * Function:	H5G_link_cmp_name_inc
  *
- * Purpose:	Callback routine for searching 'link' messages for a particular
- *              name.
+ * Purpose:	Callback routine for comparing two link names, in
+ *              increasing alphabetic order
  *
- * Return:	Non-negative on success/Negative on failure
+ * Return:	An integer less than, equal to, or greater than zero if the
+ *              first argument is considered to be respectively less than,
+ *              equal to, or greater than the second.  If two members compare
+ *              as equal, their order in the sorted array is undefined.
+ *              (i.e. same as strcmp())
  *
  * Programmer:	Quincey Koziol
  *		koziol@ncsa.uiuc.edu
@@ -106,103 +93,110 @@ static herr_t H5G_link_build_table(H5O_loc_t *oloc, hid_t dxpl_id,
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5G_link_build_table_cb(const void *_mesg, unsigned UNUSED idx, void *_udata)
+int
+H5G_link_cmp_name_inc(const void *lnk1, const void *lnk2)
 {
-    const H5O_link_t *lnk = (const H5O_link_t *)_mesg;  /* Pointer to link */
-    H5G_link_ud1_t *udata = (H5G_link_ud1_t *)_udata;     /* 'User data' passed in */
-    herr_t ret_value=H5O_ITER_CONT;             /* Return value */
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5G_link_cmp_name_inc)
 
-    FUNC_ENTER_NOAPI_NOINIT(H5G_link_build_table_cb)
+    FUNC_LEAVE_NOAPI(HDstrcmp(((const H5O_link_t *)lnk1)->name, ((const H5O_link_t *)lnk2)->name))
+} /* end H5G_link_cmp_name_inc() */
 
-    /* check arguments */
-    HDassert(lnk);
-    HDassert(udata);
-    HDassert(udata->curr_lnk < udata->ltable->nlinks);
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_link_cmp_name_dec
+ *
+ * Purpose:	Callback routine for comparing two link names, in
+ *              decreasing alphabetic order
+ *
+ * Return:	An integer less than, equal to, or greater than zero if the
+ *              second argument is considered to be respectively less than,
+ *              equal to, or greater than the first.  If two members compare
+ *              as equal, their order in the sorted array is undefined.
+ *              (i.e. opposite strcmp())
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Sep 25 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+int
+H5G_link_cmp_name_dec(const void *lnk1, const void *lnk2)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5G_link_cmp_name_dec)
+
+    FUNC_LEAVE_NOAPI(HDstrcmp(((const H5O_link_t *)lnk2)->name, ((const H5O_link_t *)lnk1)->name))
+} /* end H5G_link_cmp_name_dec() */
 
-    /* Copy link message into table */
-    if(NULL == H5O_copy(H5O_LINK_ID, lnk, &(udata->ltable->lnks[udata->curr_lnk])))
-        HGOTO_ERROR(H5E_SYM, H5E_CANTCOPY, H5O_ITER_ERROR, "can't copy link message")
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_link_cmp_corder_inc
+ *
+ * Purpose:	Callback routine for comparing two link creation orders, in
+ *              increasing order
+ *
+ * Return:	An integer less than, equal to, or greater than zero if the
+ *              first argument is considered to be respectively less than,
+ *              equal to, or greater than the second.  If two members compare
+ *              as equal, their order in the sorted array is undefined.
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Nov  6 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+int
+H5G_link_cmp_corder_inc(const void *lnk1, const void *lnk2)
+{
+    int ret_value;              /* Return value */
 
-    /* Increment current link entry to operate on */
-    udata->curr_lnk++;
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5G_link_cmp_corder_inc)
+
+    if(((const H5O_link_t *)lnk1)->corder < ((const H5O_link_t *)lnk2)->corder)
+        ret_value = -1;
+    else if(((const H5O_link_t *)lnk1)->corder > ((const H5O_link_t *)lnk2)->corder)
+        ret_value = 1;
+    else
+        ret_value = 0;
 
-done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_link_build_table_cb() */
+} /* end H5G_link_cmp_corder_inc() */
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5G_link_build_table
+ * Function:	H5G_link_cmp_corder_dec
  *
- * Purpose:     Builds a table containing a sorted (alphabetically) list of
- *              links for a group
+ * Purpose:	Callback routine for comparing two link creation orders, in
+ *              decreasing order
  *
- * Return:	Success:        Non-negative
- *		Failure:	Negative
+ * Return:	An integer less than, equal to, or greater than zero if the
+ *              second argument is considered to be respectively less than,
+ *              equal to, or greater than the first.  If two members compare
+ *              as equal, their order in the sorted array is undefined.
  *
  * Programmer:	Quincey Koziol
- *	        Sep  6, 2005
+ *		koziol@hdfgroup.org
+ *		Nov  6 2006
  *
  *-------------------------------------------------------------------------
  */
-static herr_t
-H5G_link_build_table(H5O_loc_t *oloc, hid_t dxpl_id, const H5O_linfo_t *linfo,
-    H5L_index_t idx_type, H5_iter_order_t order, H5G_link_table_t *ltable)
+int
+H5G_link_cmp_corder_dec(const void *lnk1, const void *lnk2)
 {
-    herr_t	ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT(H5G_link_build_table)
-
-    /* Sanity check */
-    HDassert(oloc);
-    HDassert(linfo);
-    HDassert(ltable);
+    int ret_value;              /* Return value */
 
-    /* Set size of table */
-    H5_CHECK_OVERFLOW(linfo->nlinks, hsize_t, size_t);
-    ltable->nlinks = (size_t)linfo->nlinks;
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5G_link_cmp_corder_dec)
 
-    /* Allocate space for the table entries */
-    if(ltable->nlinks > 0) {
-        H5G_link_ud1_t udata;               /* User data for iteration callback */
-
-        if((ltable->lnks = H5MM_malloc(sizeof(H5O_link_t) * ltable->nlinks)) == NULL)
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
-
-        /* Set up user data for iteration */
-        udata.ltable = ltable;
-        udata.curr_lnk = 0;
-
-        /* Iterate through the link messages, adding them to the table */
-        if(H5O_iterate(oloc, H5O_LINK_ID, H5G_link_build_table_cb, &udata, dxpl_id) < 0)
-            HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "error iterating over link messages")
-
-        /* Sort link table in correct iteration order */
-        if(idx_type == H5L_INDEX_NAME) {
-            if(order == H5_ITER_INC)
-                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_obj_cmp_name_inc);
-            else if(order == H5_ITER_DEC)
-                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_obj_cmp_name_dec);
-            else
-                HDassert(order == H5_ITER_NATIVE);
-        } /* end if */
-        else {
-            HDassert(idx_type == H5L_INDEX_CRT_ORDER);
-            if(order == H5_ITER_INC)
-                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_obj_cmp_corder_inc);
-            else if(order == H5_ITER_DEC)
-                HDqsort(ltable->lnks, ltable->nlinks, sizeof(H5O_link_t), H5G_obj_cmp_corder_dec);
-            else
-                HDassert(order == H5_ITER_NATIVE);
-        } /* end else */
-    } /* end if */
+    if(((const H5O_link_t *)lnk1)->corder < ((const H5O_link_t *)lnk2)->corder)
+        ret_value = 1;
+    else if(((const H5O_link_t *)lnk1)->corder > ((const H5O_link_t *)lnk2)->corder)
+        ret_value = -1;
     else
-        ltable->lnks = NULL;
+        ret_value = 0;
 
-done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_link_build_table() */
+} /* end H5G_link_cmp_corder_dec() */
 
 
 /*-------------------------------------------------------------------------
@@ -384,464 +378,43 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5G_link_insert
+ * Function:	H5G_link_release_table
  *
- * Purpose:	Insert a new symbol into the table described by GRP_ENT in
- *		file F.	 The name of the new symbol is NAME and its symbol
- *		table entry is OBJ_ENT.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Sep  6 2005
- *
- *-------------------------------------------------------------------------
- */
-herr_t
-H5G_link_insert(H5O_loc_t *grp_oloc, H5O_link_t *obj_lnk,
-    hid_t dxpl_id)
-{
-    herr_t     ret_value = SUCCEED;       /* Return value */
-
-    FUNC_ENTER_NOAPI(H5G_link_insert, FAIL)
-
-    /* check arguments */
-    HDassert(grp_oloc && grp_oloc->file);
-    HDassert(obj_lnk);
-
-    /* Insert link message into group */
-    if(H5O_modify(grp_oloc, H5O_LINK_ID, H5O_NEW_MESG, 0, H5O_UPDATE_TIME, obj_lnk, dxpl_id) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create message")
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_link_insert() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_link_get_name_by_idx
- *
- * Purpose:     Returns the name of objects in the group by giving index.
- *
- * Return:	Success:        Non-negative, length of name
- *		Failure:	Negative
- *
- * Programmer:	Quincey Koziol
- *	        Sep  6, 2005
- *
- *-------------------------------------------------------------------------
- */
-ssize_t
-H5G_link_get_name_by_idx(H5O_loc_t *oloc, hid_t dxpl_id,
-    const H5O_linfo_t *linfo, H5L_index_t idx_type, H5_iter_order_t order,
-    hsize_t idx, char* name, size_t size)
-{
-    H5G_link_table_t    ltable = {0, NULL};         /* Link table */
-    ssize_t		ret_value;      /* Return value */
-
-    FUNC_ENTER_NOAPI(H5G_link_get_name_by_idx, FAIL)
-
-    /* Sanity check */
-    HDassert(oloc);
-
-    /* Build table of all link messages */
-    if(H5G_link_build_table(oloc, dxpl_id, linfo, idx_type, order, &ltable) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create link message table")
-
-    /* Check for going out of bounds */
-    if(idx >= ltable.nlinks)
-	HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "index out of bound")
-
-    /* Get the length of the name */
-    ret_value = (ssize_t)HDstrlen(ltable.lnks[idx].name);
-
-    /* Copy the name into the user's buffer, if given */
-    if(name) {
-        HDstrncpy(name, ltable.lnks[idx].name, MIN((size_t)(ret_value + 1), size));
-        if((size_t)ret_value >= size)
-            name[size - 1]='\0';
-    } /* end if */
-
-done:
-    /* Release link table */
-    if(ltable.lnks)
-        /* Free link table information */
-        if(H5G_obj_release_table(&ltable) < 0)
-            HDONE_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to release link table")
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_link_get_name_by_idx() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_link_get_type_by_idx
- *
- * Purpose:     Returns the type of objects in the group by giving index.
+ * Purpose:     Release table containing a list of links for a group
  *
  * Return:	Success:        Non-negative
  *		Failure:	Negative
  *
  * Programmer:	Quincey Koziol
- *	        Sep 12, 2005
- *
- *-------------------------------------------------------------------------
- */
-H5G_obj_t
-H5G_link_get_type_by_idx(H5O_loc_t *oloc, hid_t dxpl_id, const H5O_linfo_t *linfo,
-    hsize_t idx)
-{
-    H5G_link_table_t    ltable = {0, NULL};         /* Link table */
-    H5G_obj_t		ret_value;      /* Return value */
-
-    FUNC_ENTER_NOAPI(H5G_link_get_type_by_idx, H5G_UNKNOWN)
-
-    /* Sanity check */
-    HDassert(oloc);
-
-    /* Build table of all link messages */
-    if(H5G_link_build_table(oloc, dxpl_id, linfo, H5L_INDEX_NAME, H5_ITER_INC, &ltable) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, H5G_UNKNOWN, "can't create link message table")
-
-    /* Check for going out of bounds */
-    if(idx >= ltable.nlinks)
-	HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, H5G_UNKNOWN, "index out of bound")
-
-    /* Determine type of object */
-    if(ltable.lnks[idx].type == H5L_TYPE_SOFT)
-        ret_value = H5G_LINK;
-    else if(ltable.lnks[idx].type >= H5L_TYPE_UD_MIN)
-        ret_value = H5G_UDLINK;
-    else if(ltable.lnks[idx].type == H5L_TYPE_HARD){
-        H5O_loc_t tmp_oloc;             /* Temporary object location */
-
-        /* Build temporary object location */
-        tmp_oloc.file = oloc->file;
-        tmp_oloc.addr = ltable.lnks[idx].u.hard.addr;
-
-        /* Get the type of the object */
-        if((ret_value = H5O_obj_type(&tmp_oloc, dxpl_id)) == H5G_UNKNOWN)
-            HGOTO_ERROR(H5E_SYM, H5E_BADTYPE, H5G_UNKNOWN, "can't determine object type")
-    } else {
-        HGOTO_ERROR(H5E_SYM, H5E_BADTYPE, H5G_UNKNOWN, "unknown link type")
-    } /* end else */
-
-done:
-    /* Release link table */
-    if(ltable.lnks)
-        /* Free link table information */
-        if(H5G_obj_release_table(&ltable) < 0)
-            HDONE_ERROR(H5E_SYM, H5E_CANTFREE, H5G_UNKNOWN, "unable to release link table")
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_link_get_type_by_idx() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_link_remove_cb
- *
- * Purpose:	Callback routine for deleting 'link' message for a particular
- *              name.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Sep  5 2005
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5G_link_remove_cb(const void *_mesg, unsigned UNUSED idx, void *_udata)
-{
-    const H5O_link_t *lnk = (const H5O_link_t *)_mesg;  /* Pointer to link */
-    H5G_link_ud2_t *udata = (H5G_link_ud2_t *)_udata;     /* 'User data' passed in */
-    herr_t ret_value = H5O_ITER_CONT;           /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT(H5G_link_remove_cb)
-
-    /* check arguments */
-    HDassert(lnk);
-    HDassert(udata);
-
-    /* If we've found the right link, get the object type */
-    if(HDstrcmp(lnk->name, udata->name) == 0) {
-        switch(lnk->type)
-        {
-            case H5L_TYPE_HARD:
-                {
-                    H5O_loc_t tmp_oloc;             /* Temporary object location */
-
-                    /* Build temporary object location */
-                    tmp_oloc.file = udata->file;
-                    tmp_oloc.addr = lnk->u.hard.addr;
-
-                    /* Get the type of the object */
-                    /* Note: no way to check for error :-( */
-                    *(udata->obj_type) = H5O_obj_type(&tmp_oloc, udata->dxpl_id);
-                }
-                break;
-
-            case H5L_TYPE_SOFT:
-                *(udata->obj_type) = H5G_LINK;
-                break;
-
-            default:  /* User-defined link */
-                if(lnk->type < H5L_TYPE_UD_MIN)
-                   HGOTO_ERROR(H5E_SYM, H5E_BADVALUE, FAIL, "unknown link type")
-
-                *(udata->obj_type) = H5G_UDLINK;
-        }
-        /* Stop the iteration, we found the correct link */
-        HGOTO_DONE(H5O_ITER_STOP)
-    } /* end if */
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_link_remove_cb() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_link_remove
- *
- * Purpose:	Remove NAME from links.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *              Monday, September 19, 2005
- *
- *-------------------------------------------------------------------------
- */
-herr_t
-H5G_link_remove(const H5O_loc_t *oloc, const char *name, H5G_obj_t *obj_type,
-    hid_t dxpl_id)
-{
-    H5G_link_ud2_t udata;               /* Data to pass through OH iteration */
-    herr_t ret_value = SUCCEED;         /* Return value */
-
-    FUNC_ENTER_NOAPI(H5G_link_remove, FAIL)
-
-    HDassert(oloc && oloc->file);
-    HDassert(name && *name);
-
-    /* Initialize data to pass through object header iteration */
-    udata.name = name;
-    udata.file = oloc->file;
-    udata.dxpl_id = dxpl_id;
-    udata.obj_type = obj_type;
-
-    /* Iterate over the link messages to delete the right one */
-    if(H5O_remove_op(oloc, H5O_LINK_ID, H5O_FIRST, H5G_link_remove_cb, &udata, TRUE, dxpl_id) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTDELETE, FAIL, "unable to delete link message")
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_link_remove() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_link_iterate
- *
- * Purpose:	Iterate over the links in a group
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *              Monday, October  3, 2005
+ *	        Sep  6, 2005
  *
  *-------------------------------------------------------------------------
  */
 herr_t
-H5G_link_iterate(H5O_loc_t *oloc, hid_t dxpl_id, const H5O_linfo_t *linfo, 
-    H5_iter_order_t order, hid_t gid, hbool_t lib_internal, int skip,
-    int *last_obj, H5G_link_iterate_t op, void *op_data)
+H5G_link_release_table(H5G_link_table_t *ltable)
 {
-    H5G_link_table_t    ltable = {0, NULL};     /* Link table */
-    size_t              u;                      /* Local index variable */
-    herr_t		ret_value;
+    size_t      u;                      /* Local index variable */
+    herr_t	ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_NOAPI(H5G_link_iterate, FAIL)
+    FUNC_ENTER_NOAPI_NOINIT(H5G_link_release_table)
 
     /* Sanity check */
-    HDassert(oloc);
-    HDassert(lib_internal || H5I_GROUP == H5I_get_type(gid));
-    HDassert(op.lib_op);
-
-    /* Build table of all link messages */
-    if(H5G_link_build_table(oloc, dxpl_id, linfo, H5L_INDEX_NAME, order, &ltable) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create link message table")
-
-    /* Iterate over link messages */
-    for(u = 0, ret_value = H5B_ITER_CONT; u < ltable.nlinks && !ret_value; u++) {
-        if(skip > 0)
-            --skip;
-        else {
-            /* Check for internal callback with link info */
-            if(lib_internal)
-                ret_value = (op.lib_op)(&(ltable.lnks[u]), op_data);
-            else
-                ret_value = (op.app_op)(gid, ltable.lnks[u].name, op_data);
-        } /* end else */
-
-        /* Increment the number of entries passed through */
-        /* (whether we skipped them or not) */
-        (*last_obj)++;
-    } /* end for */
-
-    /* Check for callback failure and pass along return value */
-    if(ret_value < 0)
-        HERROR(H5E_SYM, H5E_CANTNEXT, "iteration operator failed");
-
-done:
-    /* Release link table */
-    if(ltable.lnks)
-        /* Free link table information */
-        if(H5G_obj_release_table(&ltable) < 0)
-            HDONE_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to release link table")
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_link_iterate() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_link_lookup_cb
- *
- * Purpose:	Callback routine for searching 'link' messages for a particular
- *              name & gettting object location for it
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Sep 20 2005
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5G_link_lookup_cb(const void *_mesg, unsigned UNUSED idx, void *_udata)
-{
-    const H5O_link_t *lnk = (const H5O_link_t *)_mesg;  /* Pointer to link */
-    H5G_link_ud4_t *udata = (H5G_link_ud4_t *)_udata;     /* 'User data' passed in */
-    herr_t ret_value = H5O_ITER_CONT;           /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT(H5G_link_lookup_cb)
-
-    /* check arguments */
-    HDassert(lnk);
-    HDassert(udata);
-
-    /* Check for name to get information */
-    if(HDstrcmp(lnk->name, udata->name) == 0) {
-        if(udata->lnk) {
-            /* Copy link information */
-            if(NULL == H5O_copy(H5O_LINK_ID, lnk, udata->lnk))
-                HGOTO_ERROR(H5E_SYM, H5E_CANTCOPY, H5O_ITER_ERROR, "can't copy link message")
-        } /* end if */
+    HDassert(ltable);
 
-        /* Indicate that the correct link was found */
-        udata->found = TRUE;
+    /* Release link info, if any */
+    if(ltable->nlinks > 0) {
+        /* Free link message information */
+        for(u = 0; u < ltable->nlinks; u++)
+            if(H5O_reset(H5O_LINK_ID, &(ltable->lnks[u])) < 0)
+                HGOTO_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to release link message")
 
-        /* Stop iteration now */
-        HGOTO_DONE(H5O_ITER_STOP)
+        /* Free table of links */
+        H5MM_xfree(ltable->lnks);
     } /* end if */
+    else
+        HDassert(ltable->lnks == NULL);
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_link_lookup_cb() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_link_lookup
- *
- * Purpose:	Look up an object relative to a group, using link messages.
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Sep 20 2005
- *
- *-------------------------------------------------------------------------
- */
-herr_t
-H5G_link_lookup(H5O_loc_t *oloc, const char *name, H5O_link_t *lnk,
-    hid_t dxpl_id)
-{
-    H5G_link_ud4_t udata;               /* User data for iteration callback */
-    herr_t     ret_value = SUCCEED;     /* Return value */
-
-    FUNC_ENTER_NOAPI(H5G_link_lookup, FAIL)
-
-    /* check arguments */
-    HDassert(lnk && oloc->file);
-    HDassert(name && *name);
-
-    /* Set up user data for iteration */
-    udata.name = name;
-    udata.lnk = lnk;
-    udata.found = FALSE;
-
-    /* Iterate through the link messages, adding them to the table */
-    if(H5O_iterate(oloc, H5O_LINK_ID, H5G_link_lookup_cb, &udata, dxpl_id) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "error iterating over link messages")
-
-    /* Check if we found the link we were looking for */
-    if(!udata.found)
-        HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "object not found")
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_link_lookup() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_link_lookup_by_idx
- *
- * Purpose:	Look up an object in a group using link messages,
- *              according to the order of an index
- *
- * Return:	Non-negative on success/Negative on failure
- *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Nov  6 2006
- *
- *-------------------------------------------------------------------------
- */
-herr_t
-H5G_link_lookup_by_idx(H5O_loc_t *oloc, hid_t dxpl_id, const H5O_linfo_t *linfo,
-    H5L_index_t idx_type, H5_iter_order_t order, hsize_t n, H5O_link_t *lnk)
-{
-    H5G_link_table_t    ltable = {0, NULL};     /* Link table */
-    herr_t     ret_value = SUCCEED;     /* Return value */
-
-    FUNC_ENTER_NOAPI(H5G_link_lookup_by_idx, FAIL)
-
-    /* check arguments */
-    HDassert(oloc && oloc->file);
-    HDassert(linfo);
-    HDassert(lnk);
-
-    /* Build table of all link messages, sorted according to desired order */
-    if(H5G_link_build_table(oloc, dxpl_id, linfo, idx_type, order, &ltable) < 0)
-        HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "can't create link message table")
-
-    /* Check for going out of bounds */
-    if(n >= ltable.nlinks)
-	HGOTO_ERROR(H5E_ARGS, H5E_BADRANGE, FAIL, "index out of bound")
-
-    /* Copy link information */
-    if(NULL == H5O_copy(H5O_LINK_ID, &ltable.lnks[n], lnk))
-        HGOTO_ERROR(H5E_SYM, H5E_CANTCOPY, H5O_ITER_ERROR, "can't copy link message")
-
-done:
-    /* Release link table */
-    if(ltable.lnks)
-        /* Free link table information */
-        if(H5G_obj_release_table(&ltable) < 0)
-            HDONE_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to release link table")
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_link_lookup_by_idx() */
+} /* end H5G_link_release_table() */
 
diff --git a/src/H5Gnode.c b/src/H5Gnode.c
index 978cbe2..98123e8 100644
--- a/src/H5Gnode.c
+++ b/src/H5Gnode.c
@@ -260,12 +260,10 @@ H5G_node_encode_key(const H5F_t *f, const H5B_t UNUSED *bt, uint8_t *raw, void *
  * Programmer:	Quincey Koziol
  *              Friday, February 28, 2003
  *
- * Modifications:
- *
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5G_node_debug_key (FILE *stream, H5F_t *f, hid_t dxpl_id, int indent, int fwidth,
+H5G_node_debug_key(FILE *stream, H5F_t *f, hid_t dxpl_id, int indent, int fwidth,
 		      const void *_key, const void *_udata)
 {
     const H5G_node_key_t   *key = (const H5G_node_key_t *) _key;
@@ -280,8 +278,7 @@ H5G_node_debug_key (FILE *stream, H5F_t *f, hid_t dxpl_id, int indent, int fwidt
     HDfprintf(stream, "%*s%-*s %u\n", indent, "", fwidth, "Heap offset:",
         (unsigned)key->offset);
 
-    if(udata->heap_addr != 0)
-    {
+    if(udata->heap_addr != 0) {
         HDfprintf(stream, "%*s%-*s ", indent, "", fwidth, "Name:");
 
         if (NULL == (heap = H5HL_protect(f, dxpl_id, udata->heap_addr)))
@@ -292,15 +289,13 @@ H5G_node_debug_key (FILE *stream, H5F_t *f, hid_t dxpl_id, int indent, int fwidt
 
         if (H5HL_unprotect(f, dxpl_id, heap, udata->heap_addr, H5AC__NO_FLAGS_SET) < 0)
             HGOTO_ERROR(H5E_SYM, H5E_PROTECT, FAIL, "unable to unprotect symbol name");
-    }
+    } /* end if */
     else
-    {
         HDfprintf(stream, "%*s%-*s ", indent, "", fwidth, "Cannot get name; heap address not specified\n");
-    }
 
 done:
     FUNC_LEAVE_NOAPI(ret_value);
-}
+} /* end H5G_node_debug_key() */
 
 
 /*-------------------------------------------------------------------------
diff --git a/src/H5Gobj.c b/src/H5Gobj.c
index a5cea7e..c450e46 100644
--- a/src/H5Gobj.c
+++ b/src/H5Gobj.c
@@ -88,7 +88,7 @@ typedef struct {
 /********************/
 /* Local Prototypes */
 /********************/
-static herr_t H5G_obj_link_to_dense_cb(const void *_mesg, unsigned idx,
+static herr_t H5G_obj_compact_to_dense_cb(const void *_mesg, unsigned idx,
     void *_udata);
 
 
@@ -109,172 +109,6 @@ static herr_t H5G_obj_link_to_dense_cb(const void *_mesg, unsigned idx,
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5G_obj_cmp_name_inc
- *
- * Purpose:	Callback routine for comparing two link names, in
- *              increasing alphabetic order
- *
- * Return:	An integer less than, equal to, or greater than zero if the
- *              first argument is considered to be respectively less than,
- *              equal to, or greater than the second.  If two members compare
- *              as equal, their order in the sorted array is undefined.
- *              (i.e. same as strcmp())
- *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Sep  5 2005
- *
- *-------------------------------------------------------------------------
- */
-int
-H5G_obj_cmp_name_inc(const void *lnk1, const void *lnk2)
-{
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5G_obj_cmp_name_inc)
-
-    FUNC_LEAVE_NOAPI(HDstrcmp(((const H5O_link_t *)lnk1)->name, ((const H5O_link_t *)lnk2)->name))
-} /* end H5G_obj_cmp_name_inc() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_obj_cmp_name_dec
- *
- * Purpose:	Callback routine for comparing two link names, in
- *              decreasing alphabetic order
- *
- * Return:	An integer less than, equal to, or greater than zero if the
- *              second argument is considered to be respectively less than,
- *              equal to, or greater than the first.  If two members compare
- *              as equal, their order in the sorted array is undefined.
- *              (i.e. opposite strcmp())
- *
- * Programmer:	Quincey Koziol
- *		koziol@ncsa.uiuc.edu
- *		Sep 25 2006
- *
- *-------------------------------------------------------------------------
- */
-int
-H5G_obj_cmp_name_dec(const void *lnk1, const void *lnk2)
-{
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5G_obj_cmp_name_dec)
-
-    FUNC_LEAVE_NOAPI(HDstrcmp(((const H5O_link_t *)lnk2)->name, ((const H5O_link_t *)lnk1)->name))
-} /* end H5G_obj_cmp_name_dec() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_obj_cmp_corder_inc
- *
- * Purpose:	Callback routine for comparing two link creation orders, in
- *              increasing order
- *
- * Return:	An integer less than, equal to, or greater than zero if the
- *              first argument is considered to be respectively less than,
- *              equal to, or greater than the second.  If two members compare
- *              as equal, their order in the sorted array is undefined.
- *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Nov  6 2006
- *
- *-------------------------------------------------------------------------
- */
-int
-H5G_obj_cmp_corder_inc(const void *lnk1, const void *lnk2)
-{
-    int ret_value;              /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5G_obj_cmp_corder_inc)
-
-    if(((const H5O_link_t *)lnk1)->corder < ((const H5O_link_t *)lnk2)->corder)
-        ret_value = -1;
-    else if(((const H5O_link_t *)lnk1)->corder > ((const H5O_link_t *)lnk2)->corder)
-        ret_value = 1;
-    else
-        ret_value = 0;
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_obj_cmp_corder_inc() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_obj_cmp_corder_dec
- *
- * Purpose:	Callback routine for comparing two link creation orders, in
- *              decreasing order
- *
- * Return:	An integer less than, equal to, or greater than zero if the
- *              second argument is considered to be respectively less than,
- *              equal to, or greater than the first.  If two members compare
- *              as equal, their order in the sorted array is undefined.
- *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Nov  6 2006
- *
- *-------------------------------------------------------------------------
- */
-int
-H5G_obj_cmp_corder_dec(const void *lnk1, const void *lnk2)
-{
-    int ret_value;              /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5G_obj_cmp_corder_dec)
-
-    if(((const H5O_link_t *)lnk1)->corder < ((const H5O_link_t *)lnk2)->corder)
-        ret_value = 1;
-    else if(((const H5O_link_t *)lnk1)->corder > ((const H5O_link_t *)lnk2)->corder)
-        ret_value = -1;
-    else
-        ret_value = 0;
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_obj_cmp_corder_dec() */
-
-
-/*-------------------------------------------------------------------------
- * Function:	H5G_obj_release_table
- *
- * Purpose:     Release table containing a list of links for a group
- *
- * Return:	Success:        Non-negative
- *		Failure:	Negative
- *
- * Programmer:	Quincey Koziol
- *	        Sep  6, 2005
- *
- *-------------------------------------------------------------------------
- */
-herr_t
-H5G_obj_release_table(H5G_link_table_t *ltable)
-{
-    size_t      u;                      /* Local index variable */
-    herr_t	ret_value = SUCCEED;    /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT(H5G_obj_release_table)
-
-    /* Sanity check */
-    HDassert(ltable);
-
-    /* Release link info, if any */
-    if(ltable->nlinks > 0) {
-        /* Free link message information */
-        for(u = 0; u < ltable->nlinks; u++)
-            if(H5O_reset(H5O_LINK_ID, &(ltable->lnks[u])) < 0)
-                HGOTO_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to release link message")
-
-        /* Free table of links */
-        H5MM_xfree(ltable->lnks);
-    } /* end if */
-    else
-        HDassert(ltable->lnks == NULL);
-
-done:
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_obj_release_table() */
-
-
-/*-------------------------------------------------------------------------
  * Function:    H5G_obj_create
  *
  * Purpose:     Create an object header for a group and update object location info
@@ -470,9 +304,9 @@ H5G_obj_ent_encode(H5F_t *f, uint8_t **pp, const H5O_loc_t *oloc)
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5G_obj_link_to_dense_cb
+ * Function:	H5G_obj_compact_to_dense_cb
  *
- * Purpose:	Callback routine for converting 'link' messages to "dense"
+ * Purpose:	Callback routine for converting "compact" to "dense"
  *              link storage form.
  *
  * Return:	Non-negative on success/Negative on failure
@@ -484,13 +318,13 @@ H5G_obj_ent_encode(H5F_t *f, uint8_t **pp, const H5O_loc_t *oloc)
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5G_obj_link_to_dense_cb(const void *_mesg, unsigned UNUSED idx, void *_udata)
+H5G_obj_compact_to_dense_cb(const void *_mesg, unsigned UNUSED idx, void *_udata)
 {
     const H5O_link_t *lnk = (const H5O_link_t *)_mesg;  /* Pointer to link */
     H5G_obj_oh_it_ud1_t *udata = (H5G_obj_oh_it_ud1_t *)_udata;     /* 'User data' passed in */
     herr_t ret_value = H5O_ITER_CONT;   /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT(H5G_obj_link_to_dense_cb)
+    FUNC_ENTER_NOAPI_NOINIT(H5G_obj_compact_to_dense_cb)
 
     /* check arguments */
     HDassert(lnk);
@@ -502,14 +336,14 @@ H5G_obj_link_to_dense_cb(const void *_mesg, unsigned UNUSED idx, void *_udata)
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5G_obj_link_to_dense_cb() */
+} /* end H5G_obj_compact_to_dense_cb() */
 
 
 /*-------------------------------------------------------------------------
  * Function:	H5G_obj_stab_to_new_cb
  *
  * Purpose:	Callback routine for converting "symbol table" link storage to
- *              "new format" storage (either link messages or "dense" storage).
+ *              "new format" storage (either "compact" or "dense" storage).
  *
  * Return:	Non-negative on success/Negative on failure
  *
@@ -622,7 +456,7 @@ H5G_obj_insert(H5O_loc_t *grp_oloc, const char *name, H5O_link_t *obj_lnk,
             udata.linfo = &linfo;
 
             /* Iterate over the 'link' messages, inserting them into the dense link storage  */
-            if(H5O_iterate(grp_oloc, H5O_LINK_ID, H5G_obj_link_to_dense_cb, &udata, dxpl_id) < 0)
+            if(H5O_iterate(grp_oloc, H5O_LINK_ID, H5G_obj_compact_to_dense_cb, &udata, dxpl_id) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "error iterating over links")
 
             /* Remove all the 'link' messages */
@@ -696,7 +530,7 @@ H5G_obj_insert(H5O_loc_t *grp_oloc, const char *name, H5O_link_t *obj_lnk,
         } /* end if */
         else {
             /* Insert with link message */
-            if(H5G_link_insert(grp_oloc, obj_lnk, dxpl_id) < 0)
+            if(H5G_compact_insert(grp_oloc, obj_lnk, dxpl_id) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_CANTINSERT, FAIL, "unable to insert link as link message")
         } /* end else */
     } /* end else */
@@ -784,7 +618,7 @@ H5G_obj_iterate(hid_t loc_id, const char *name, H5_iter_order_t order,
         } /* end if */
         else {
             /* Get the object's name from the link messages */
-            if((ret_value = H5G_link_iterate(&(grp->oloc), dxpl_id, &linfo, order, gid, FALSE, skip, last_lnk, lnk_op, op_data)) < 0)
+            if((ret_value = H5G_compact_iterate(&(grp->oloc), dxpl_id, &linfo, order, gid, FALSE, skip, last_lnk, lnk_op, op_data)) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_BADITER, FAIL, "can't iterate over links")
         } /* end else */
     } /* end if */
@@ -898,7 +732,7 @@ H5G_obj_get_name_by_idx(H5O_loc_t *oloc, H5L_index_t idx_type,
         } /* end if */
         else {
             /* Get the object's name from the link messages */
-            if((ret_value = H5G_link_get_name_by_idx(oloc, dxpl_id, &linfo, idx_type, order, n, name, size)) < 0)
+            if((ret_value = H5G_compact_get_name_by_idx(oloc, dxpl_id, &linfo, idx_type, order, n, name, size)) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "can't locate name")
         } /* end else */
     } /* end if */
@@ -955,7 +789,7 @@ H5G_obj_get_type_by_idx(H5O_loc_t *oloc, hsize_t idx, hid_t dxpl_id)
         } /* end if */
         else {
             /* Get the object's type from the link messages */
-            if((ret_value = H5G_link_get_type_by_idx(oloc, dxpl_id, &linfo, idx)) < 0)
+            if((ret_value = H5G_compact_get_type_by_idx(oloc, dxpl_id, &linfo, idx)) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, H5G_UNKNOWN, "can't locate type")
         } /* end else */
     } /* end if */
@@ -1015,7 +849,7 @@ H5G_obj_remove(H5O_loc_t *oloc, const char *name, H5G_obj_t *obj_type, hid_t dxp
         } /* end if */
         else {
             /* Remove object from the link messages */
-            if(H5G_link_remove(oloc, name, obj_type, dxpl_id) < 0)
+            if(H5G_compact_remove(oloc, name, obj_type, dxpl_id) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "can't remove object")
         } /* end else */
     } /* end if */
@@ -1084,7 +918,7 @@ H5G_obj_remove(H5O_loc_t *oloc, const char *name, H5G_obj_t *obj_type, hid_t dxp
                     } /* end if */
 
                     /* Free link table information */
-                    if(H5G_obj_release_table(&ltable) < 0)
+                    if(H5G_link_release_table(&ltable) < 0)
                         HGOTO_ERROR(H5E_SYM, H5E_CANTFREE, FAIL, "unable to release link table")
                 } /* end if */
             } /* end else */
@@ -1136,7 +970,7 @@ H5G_obj_lookup(H5O_loc_t *grp_oloc, const char *name, H5O_link_t *lnk,
         } /* end if */
         else {
             /* Get the object's info from the link messages */
-            if(H5G_link_lookup(grp_oloc, name, lnk, dxpl_id) < 0)
+            if(H5G_compact_lookup(grp_oloc, name, lnk, dxpl_id) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "can't locate object")
         } /* end else */
     } /* end if */
@@ -1203,7 +1037,7 @@ H5G_obj_lookup_by_idx(H5O_loc_t *grp_oloc, H5L_index_t idx_type,
         } /* end if */
         else {
             /* Get the link from the link messages */
-            if(H5G_link_lookup_by_idx(grp_oloc, dxpl_id, &linfo, idx_type, order, n, lnk) < 0)
+            if(H5G_compact_lookup_by_idx(grp_oloc, dxpl_id, &linfo, idx_type, order, n, lnk) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "can't locate object")
         } /* end else */
     } /* end if */
diff --git a/src/H5Gpkg.h b/src/H5Gpkg.h
index 91819f8..b3dc299 100644
--- a/src/H5Gpkg.h
+++ b/src/H5Gpkg.h
@@ -412,27 +412,34 @@ H5_DLL int H5G_node_by_idx(H5F_t *f, hid_t dxpl_id, const void *_lt_key, haddr_t
 H5_DLL int H5G_node_copy(H5F_t *f, hid_t dxpl_id, const void *_lt_key, haddr_t addr,
 		     const void *_rt_key, void *_udata);
 
-/* Functions that understand link messages */
+/* Functions that understand links in groups */
+H5_DLL int H5G_link_cmp_name_inc(const void *lnk1, const void *lnk2);
+H5_DLL int H5G_link_cmp_name_dec(const void *lnk1, const void *lnk2);
+H5_DLL int H5G_link_cmp_corder_inc(const void *lnk1, const void *lnk2);
+H5_DLL int H5G_link_cmp_corder_dec(const void *lnk1, const void *lnk2);
 H5_DLL herr_t H5G_link_convert(H5F_t *f, hid_t dxpl_id, H5O_link_t *lnk,
     haddr_t lheap_addr, const H5G_entry_t *ent, const char *name);
 H5_DLL herr_t H5G_link_copy_file(H5F_t *dst_file, hid_t dxpl_id,
     const H5O_link_t *_src_lnk, const H5O_loc_t *src_oloc, H5O_link_t *dst_lnk,
     H5O_copy_t *cpy_info);
-H5_DLL herr_t H5G_link_insert(H5O_loc_t *grp_oloc, H5O_link_t *obj_lnk,
+H5_DLL herr_t H5G_link_release_table(H5G_link_table_t *ltable);
+
+/* Functions that understand "compact" link storage */
+H5_DLL herr_t H5G_compact_insert(H5O_loc_t *grp_oloc, H5O_link_t *obj_lnk,
     hid_t dxpl_id);
-H5_DLL ssize_t H5G_link_get_name_by_idx(H5O_loc_t *oloc, hid_t dxpl_id,
+H5_DLL ssize_t H5G_compact_get_name_by_idx(H5O_loc_t *oloc, hid_t dxpl_id,
     const H5O_linfo_t *linfo, H5L_index_t idx_type, H5_iter_order_t order,
     hsize_t idx, char *name, size_t size);
-H5_DLL H5G_obj_t H5G_link_get_type_by_idx(H5O_loc_t *oloc, hid_t dxpl_id,
+H5_DLL H5G_obj_t H5G_compact_get_type_by_idx(H5O_loc_t *oloc, hid_t dxpl_id,
     const H5O_linfo_t *linfo, hsize_t idx);
-H5_DLL herr_t H5G_link_remove(const H5O_loc_t *oloc, const char *name,
+H5_DLL herr_t H5G_compact_remove(const H5O_loc_t *oloc, const char *name,
     H5G_obj_t *obj_type, hid_t dxpl_id);
-H5_DLL herr_t H5G_link_iterate(H5O_loc_t *oloc, hid_t dxpl_id, const H5O_linfo_t *linfo, 
+H5_DLL herr_t H5G_compact_iterate(H5O_loc_t *oloc, hid_t dxpl_id, const H5O_linfo_t *linfo, 
     H5_iter_order_t order, hid_t gid, hbool_t lib_internal, int skip,
     int *last_obj, H5G_link_iterate_t op, void *op_data);
-H5_DLL herr_t H5G_link_lookup(H5O_loc_t *grp_oloc, const char *name,
+H5_DLL herr_t H5G_compact_lookup(H5O_loc_t *grp_oloc, const char *name,
     H5O_link_t *lnk, hid_t dxpl_id);
-H5_DLL herr_t H5G_link_lookup_by_idx(H5O_loc_t *oloc, hid_t dxpl_id,
+H5_DLL herr_t H5G_compact_lookup_by_idx(H5O_loc_t *oloc, hid_t dxpl_id,
     const H5O_linfo_t *linfo, H5L_index_t idx_type, H5_iter_order_t order,
     hsize_t n, H5O_link_t *lnk);
 
@@ -460,12 +467,7 @@ H5_DLL herr_t H5G_dense_remove(H5F_t *f, hid_t dxpl_id, const H5O_linfo_t *linfo
 H5_DLL herr_t H5G_dense_delete(H5F_t *f, hid_t dxpl_id, H5O_linfo_t *linfo,
     hbool_t adj_link);
 
-/* Functions that understand objects */
-H5_DLL int H5G_obj_cmp_name_inc(const void *lnk1, const void *lnk2);
-H5_DLL int H5G_obj_cmp_name_dec(const void *lnk1, const void *lnk2);
-H5_DLL int H5G_obj_cmp_corder_inc(const void *lnk1, const void *lnk2);
-H5_DLL int H5G_obj_cmp_corder_dec(const void *lnk1, const void *lnk2);
-H5_DLL herr_t H5G_obj_release_table(H5G_link_table_t *ltable);
+/* Functions that understand group objects */
 H5_DLL herr_t H5G_obj_create(H5F_t *f, hid_t dxpl_id, const H5O_ginfo_t *ginfo,
     const H5O_linfo_t *linfo, H5O_loc_t *oloc/*out*/);
 H5_DLL herr_t H5G_obj_insert(H5O_loc_t *grp_oloc, const char *name,
diff --git a/src/Makefile.am b/src/Makefile.am
index fa24970..3f18498 100755
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -50,8 +50,9 @@ libhdf5_la_SOURCES= H5.c H5checksum.c H5dbg.c H5system.c H5timer.c H5trace.c \
         H5FDdirect.c H5FDfamily.c H5FDlog.c H5FDmpi.c H5FDmpio.c   \
         H5FDmpiposix.c H5FDmulti.c H5FDsec2.c H5FDstdio.c           \
         H5FDstream.c H5FL.c H5FO.c H5FS.c H5FScache.c H5FSdbg.c H5FSsection.c \
-        H5G.c H5Gbtree2.c H5Gdense.c H5Gdeprec.c H5Gent.c H5Glink.c H5Gloc.c \
-        H5Gname.c H5Gnode.c H5Gobj.c H5Goh.c H5Gstab.c H5Gtest.c H5Gtraverse.c \
+        H5G.c H5Gbtree2.c H5Gcompact.c H5Gdense.c H5Gdeprec.c H5Gent.c H5Glink.c \
+        H5Gloc.c H5Gname.c H5Gnode.c H5Gobj.c H5Goh.c H5Gstab.c H5Gtest.c \
+        H5Gtraverse.c \
         H5HF.c H5HFbtree2.c H5HFcache.c H5HFdbg.c H5HFdblock.c H5HFdtable.c \
         H5HFhdr.c H5HFhuge.c H5HFiblock.c H5HFiter.c H5HFman.c H5HFsection.c \
         H5HFspace.c H5HFstat.c H5HFtest.c H5HFtiny.c \
diff --git a/src/Makefile.in b/src/Makefile.in
index aa65579..ef11c1e 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -90,7 +90,7 @@ am_libhdf5_la_OBJECTS = H5.lo H5checksum.lo H5dbg.lo H5system.lo \
 	H5FDdirect.lo H5FDfamily.lo H5FDlog.lo H5FDmpi.lo H5FDmpio.lo \
 	H5FDmpiposix.lo H5FDmulti.lo H5FDsec2.lo H5FDstdio.lo \
 	H5FDstream.lo H5FL.lo H5FO.lo H5FS.lo H5FScache.lo H5FSdbg.lo \
-	H5FSsection.lo H5G.lo H5Gbtree2.lo H5Gdense.lo H5Gdeprec.lo \
+	H5FSsection.lo H5G.lo H5Gbtree2.lo H5Gcompact.lo H5Gdense.lo H5Gdeprec.lo \
 	H5Gent.lo H5Glink.lo H5Gloc.lo H5Gname.lo H5Gnode.lo H5Gobj.lo \
 	H5Goh.lo H5Gstab.lo H5Gtest.lo H5Gtraverse.lo H5HF.lo \
 	H5HFbtree2.lo H5HFcache.lo H5HFdbg.lo H5HFdblock.lo \
@@ -404,7 +404,7 @@ libhdf5_la_SOURCES = H5.c H5checksum.c H5dbg.c H5system.c H5timer.c H5trace.c \
         H5FDdirect.c H5FDfamily.c H5FDlog.c H5FDmpi.c H5FDmpio.c   \
         H5FDmpiposix.c H5FDmulti.c H5FDsec2.c H5FDstdio.c           \
         H5FDstream.c H5FL.c H5FO.c H5FS.c H5FScache.c H5FSdbg.c H5FSsection.c \
-        H5G.c H5Gbtree2.c H5Gdense.c H5Gdeprec.c H5Gent.c H5Glink.c H5Gloc.c \
+        H5G.c H5Gbtree2.c H5Gcompact.c H5Gdense.c H5Gdeprec.c H5Gent.c H5Glink.c H5Gloc.c \
         H5Gname.c H5Gnode.c H5Gobj.c H5Goh.c H5Gstab.c H5Gtest.c H5Gtraverse.c \
         H5HF.c H5HFbtree2.c H5HFcache.c H5HFdbg.c H5HFdblock.c H5HFdtable.c \
         H5HFhdr.c H5HFhuge.c H5HFiblock.c H5HFiter.c H5HFman.c H5HFsection.c \
@@ -608,6 +608,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Fsuper.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5G.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Gbtree2.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Gcompact.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Gdense.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Gdeprec.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Gent.Plo@am__quote@