[svn-r13498] Description:

	Eliminate storing # of links in "link info" message, regenerate it
when the object is opened instead.

Tested on:
	FreeBSD/32 6.2 (duty)
	Mac OS X/32 10.4.8 (amazon)

16 files changed, 164 insertions, 67 deletions

diff --git a/src/H5G.c b/src/H5G.c
index 64eb8c2..b193e61 100644
--- a/src/H5G.c
+++ b/src/H5G.c
@@ -561,7 +561,7 @@ H5Gget_create_plist(hid_t group_id)
         H5O_linfo_t linfo;		/* Link info message            */
 
         /* Read the link info */
-        if(NULL == H5O_msg_read(&(grp->oloc), H5O_LINFO_ID, &linfo, H5AC_ind_dxpl_id))
+        if(NULL == H5G_obj_get_linfo(&(grp->oloc), &linfo, H5AC_ind_dxpl_id))
             HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "can't get link info")
 
         /* Set the link info for the property list */
diff --git a/src/H5Gcompact.c b/src/H5Gcompact.c
index 9476716..90ac2d0 100644
--- a/src/H5Gcompact.c
+++ b/src/H5Gcompact.c
@@ -183,7 +183,7 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5G_compact_insert(H5O_loc_t *grp_oloc, H5O_link_t *obj_lnk,
+H5G_compact_insert(const H5O_loc_t *grp_oloc, H5O_link_t *obj_lnk,
     hid_t dxpl_id)
 {
     herr_t     ret_value = SUCCEED;       /* Return value */
diff --git a/src/H5Gdense.c b/src/H5Gdense.c
index ded0549..0b7ae9e 100644
--- a/src/H5Gdense.c
+++ b/src/H5Gdense.c
@@ -303,10 +303,10 @@ H5G_dense_create(H5F_t *f, hid_t dxpl_id, H5O_linfo_t *linfo)
         HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, FAIL, "unable to create fractal heap")
 
     /* Retrieve the heap's address in the file */
-    if(H5HF_get_heap_addr(fheap, &(linfo->link_fheap_addr)) < 0)
+    if(H5HF_get_heap_addr(fheap, &(linfo->fheap_addr)) < 0)
         HGOTO_ERROR(H5E_SYM, H5E_CANTGETSIZE, FAIL, "can't get fractal heap address")
 #ifdef QAK
-HDfprintf(stderr, "%s: linfo->link_fheap_addr = %a\n", FUNC, linfo->link_fheap_addr);
+HDfprintf(stderr, "%s: linfo->fheap_addr = %a\n", FUNC, linfo->fheap_addr);
 #endif /* QAK */
 
     /* Retrieve the heap's ID length in the file */
@@ -386,7 +386,7 @@ H5G_dense_insert(H5F_t *f, hid_t dxpl_id, const H5O_linfo_t *linfo,
     HDassert(linfo);
     HDassert(lnk);
 #ifdef QAK
-HDfprintf(stderr, "%s: linfo->link_fheap_addr = %a\n", FUNC, linfo->link_fheap_addr);
+HDfprintf(stderr, "%s: linfo->fheap_addr = %a\n", FUNC, linfo->fheap_addr);
 HDfprintf(stderr, "%s: linfo->name_bt2_addr = %a\n", FUNC, linfo->name_bt2_addr);
 #endif /* QAK */
 
@@ -410,7 +410,7 @@ HDfprintf(stderr, "%s: HDstrlen(lnk->name) = %Zu, link_size = %Zu\n", FUNC, HDst
 	HGOTO_ERROR(H5E_SYM, H5E_CANTENCODE, FAIL, "can't encode link")
 
     /* Open the fractal heap */
-    if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->link_fheap_addr)))
+    if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->fheap_addr)))
         HGOTO_ERROR(H5E_SYM, H5E_CANTOPENOBJ, FAIL, "unable to open fractal heap")
 
     /* Insert the serialized link into the fractal heap */
@@ -520,7 +520,7 @@ H5G_dense_lookup(H5F_t *f, hid_t dxpl_id, const H5O_linfo_t *linfo,
     HDassert(lnk);
 
     /* Open the fractal heap */
-    if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->link_fheap_addr)))
+    if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->fheap_addr)))
         HGOTO_ERROR(H5E_SYM, H5E_CANTOPENOBJ, FAIL, "unable to open fractal heap")
 
     /* Construct the user data for v2 B-tree callback */
@@ -687,7 +687,7 @@ H5G_dense_lookup_by_idx(H5F_t *f, hid_t dxpl_id, const H5O_linfo_t *linfo,
         H5G_bt2_ud_lbi_t udata;        /* User data for v2 B-tree link lookup */
 
         /* Open the fractal heap */
-        if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->link_fheap_addr)))
+        if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->fheap_addr)))
             HGOTO_ERROR(H5E_SYM, H5E_CANTOPENOBJ, FAIL, "unable to open fractal heap")
 
         /* Construct the user data for v2 B-tree callback */
@@ -1011,7 +1011,7 @@ H5G_dense_iterate(H5F_t *f, hid_t dxpl_id, const H5O_linfo_t *linfo,
         H5G_bt2_ud_it_t udata;              /* User data for iterator callback */
 
         /* Open the fractal heap */
-        if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->link_fheap_addr)))
+        if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->fheap_addr)))
             HGOTO_ERROR(H5E_SYM, H5E_CANTOPENOBJ, FAIL, "unable to open fractal heap")
 
         /* Construct the user data for v2 B-tree iterator callback */
@@ -1205,7 +1205,7 @@ H5G_dense_get_name_by_idx(H5F_t *f, hid_t dxpl_id, H5O_linfo_t *linfo,
         H5G_bt2_ud_gnbi_t udata;       /* User data for v2 B-tree callback */
 
         /* Open the fractal heap */
-        if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->link_fheap_addr)))
+        if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->fheap_addr)))
             HGOTO_ERROR(H5E_SYM, H5E_CANTOPENOBJ, FAIL, "unable to open fractal heap")
 
         /* Set up the user data for the v2 B-tree 'record remove' callback */
@@ -1464,7 +1464,7 @@ H5G_dense_remove(H5F_t *f, hid_t dxpl_id, const H5O_linfo_t *linfo,
     HDassert(name && *name);
 
     /* Open the fractal heap */
-    if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->link_fheap_addr)))
+    if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->fheap_addr)))
         HGOTO_ERROR(H5E_SYM, H5E_CANTOPENOBJ, FAIL, "unable to open fractal heap")
 
     /* Set up the user data for the v2 B-tree 'record remove' callback */
@@ -1696,7 +1696,7 @@ H5G_dense_remove_by_idx(H5F_t *f, hid_t dxpl_id, const H5O_linfo_t *linfo,
         H5G_bt2_ud_rmbi_t udata;            /* User data for v2 B-tree record removal */
 
         /* Open the fractal heap */
-        if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->link_fheap_addr)))
+        if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->fheap_addr)))
             HGOTO_ERROR(H5E_SYM, H5E_CANTOPENOBJ, FAIL, "unable to open fractal heap")
 
         /* Set up the user data for the v2 B-tree 'remove by index' callback */
@@ -1772,7 +1772,7 @@ H5G_dense_delete(H5F_t *f, hid_t dxpl_id, H5O_linfo_t *linfo, hbool_t adj_link)
         H5G_bt2_ud_rm_t udata;          /* User data for v2 B-tree record removal */
 
         /* Open the fractal heap */
-        if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->link_fheap_addr)))
+        if(NULL == (fheap = H5HF_open(f, dxpl_id, linfo->fheap_addr)))
             HGOTO_ERROR(H5E_SYM, H5E_CANTOPENOBJ, FAIL, "unable to open fractal heap")
 
         /* Set up the user data for the v2 B-tree 'record remove' callback */
@@ -1815,9 +1815,9 @@ H5G_dense_delete(H5F_t *f, hid_t dxpl_id, H5O_linfo_t *linfo, hbool_t adj_link)
         HDassert(!H5F_addr_defined(linfo->corder_bt2_addr));
 
     /* Delete the fractal heap */
-    if(H5HF_delete(f, dxpl_id, linfo->link_fheap_addr) < 0)
+    if(H5HF_delete(f, dxpl_id, linfo->fheap_addr) < 0)
         HGOTO_ERROR(H5E_SYM, H5E_CANTDELETE, FAIL, "unable to delete fractal heap")
-    linfo->link_fheap_addr = HADDR_UNDEF;
+    linfo->fheap_addr = HADDR_UNDEF;
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
diff --git a/src/H5Gobj.c b/src/H5Gobj.c
index f262c4b..e91b162 100644
--- a/src/H5Gobj.c
+++ b/src/H5Gobj.c
@@ -77,7 +77,7 @@ typedef struct {
  * a new-format group
  */
 typedef struct {
-    H5O_loc_t   *grp_oloc;              /* Pointer to group for insertion */
+    const H5O_loc_t   *grp_oloc;              /* Pointer to group for insertion */
     hid_t       dxpl_id;                /* DXPL during insertion */
 } H5G_obj_stab_it_ud1_t;
 
@@ -308,6 +308,57 @@ H5G_obj_ent_encode(const H5F_t *f, uint8_t **pp, const H5O_loc_t *oloc)
 
 
 /*-------------------------------------------------------------------------
+ * Function:    H5G_obj_get_linfo
+ *
+ * Purpose:     Retrieves the "link info" message for an object.  Also
+ *              sets the number of links correctly, if it isn't set up yet.
+ *
+ * Return:	Success:	Ptr to message in native format.
+ *              Failure:        NULL
+ *
+ * Programmer:  Quincey Koziol
+ *              koziol@hdfgroup.org
+ *              Mar 11 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+H5O_linfo_t *
+H5G_obj_get_linfo(const H5O_loc_t *grp_oloc, H5O_linfo_t *linfo, hid_t dxpl_id)
+{
+    H5O_linfo_t *ret_value;     /* Return value */
+    
+    FUNC_ENTER_NOAPI(H5G_obj_get_linfo, NULL)
+
+    /* check arguments */
+    HDassert(grp_oloc);
+
+    /* Retrieve the "link info" structure */
+    if(ret_value = H5O_msg_read(grp_oloc, H5O_LINFO_ID, linfo, dxpl_id)) {
+        /* Check if we don't know how many links there are */
+        if(ret_value->nlinks == HSIZET_MAX) {
+            /* Check if we are using "dense" link storage */
+            if(H5F_addr_defined(ret_value->fheap_addr)) {
+                /* Retrieve # of records in "name" B-tree */
+                /* (should be same # of records in all indices) */
+                if(H5B2_get_nrec(grp_oloc->file, dxpl_id, H5G_BT2_NAME, ret_value->name_bt2_addr, &ret_value->nlinks) < 0)
+                    HGOTO_ERROR(H5E_SYM, H5E_CANTGET, NULL, "can't retrieve # of records in index")
+            } /* end if */
+            else {
+                /* Retrieve # of links from object header */
+                if(H5O_get_nlinks(grp_oloc, dxpl_id, &ret_value->nlinks) < 0)
+                    HGOTO_ERROR(H5E_SYM, H5E_CANTGET, NULL, "can't retrieve # of links for object")
+            } /* end if */
+        } /* end if */
+    } /* end if */
+    else
+        HGOTO_ERROR(H5E_SYM, H5E_CANTGET, NULL, "link info message not present")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5G_obj_get_linfo() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5G_obj_compact_to_dense_cb
  *
  * Purpose:	Callback routine for converting "compact" to "dense"
@@ -397,7 +448,7 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5G_obj_insert(H5O_loc_t *grp_oloc, const char *name, H5O_link_t *obj_lnk,
+H5G_obj_insert(const H5O_loc_t *grp_oloc, const char *name, H5O_link_t *obj_lnk,
     hbool_t adj_link, hid_t dxpl_id)
 {
     H5O_linfo_t linfo;		/* Link info message */
@@ -414,7 +465,7 @@ H5G_obj_insert(H5O_loc_t *grp_oloc, const char *name, H5O_link_t *obj_lnk,
 
     /* Check if we have information about the number of objects in this group */
     /* (by attempting to get the link info message for this group) */
-    if(H5O_msg_read(grp_oloc, H5O_LINFO_ID, &linfo, dxpl_id)) {
+    if(H5G_obj_get_linfo(grp_oloc, &linfo, dxpl_id)) {
         H5O_ginfo_t ginfo;	/* Group info message */
         size_t link_msg_size;   /* Size of new link message in the file */
 
@@ -443,7 +494,7 @@ H5G_obj_insert(H5O_loc_t *grp_oloc, const char *name, H5O_link_t *obj_lnk,
         /* (If the encoded form of the link is too large to fit into an object
          *  header message, convert to using dense link storage instead of link messages)
          */
-        if(H5F_addr_defined(linfo.link_fheap_addr))
+        if(H5F_addr_defined(linfo.fheap_addr))
             use_new_dense = TRUE;
         else if(linfo.nlinks < ginfo.max_compact && link_msg_size < H5O_MESG_MAX_SIZE)
             use_new_dense = FALSE;
@@ -608,7 +659,7 @@ H5G_obj_iterate(hid_t loc_id, const char *group_name,
         HGOTO_ERROR(H5E_ATOM, H5E_BADATOM, FAIL, "bad group ID")
 
     /* Attempt to get the link info for this group */
-    if(H5O_msg_read(&(grp->oloc), H5O_LINFO_ID, &linfo, dxpl_id)) {
+    if(H5G_obj_get_linfo(&(grp->oloc), &linfo, dxpl_id)) {
         /* Check for going out of bounds */
         if(skip > 0 && (size_t)skip >= linfo.nlinks)
             HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "index out of bound")
@@ -620,7 +671,7 @@ H5G_obj_iterate(hid_t loc_id, const char *group_name,
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "creation order not tracked for links in group")
         } /* end if */
 
-        if(H5F_addr_defined(linfo.link_fheap_addr)) {
+        if(H5F_addr_defined(linfo.fheap_addr)) {
             /* Iterate over the links in the group, building a table of the link messages */
             if((ret_value = H5G_dense_iterate(grp->oloc.file, dxpl_id, &linfo, idx_type, order, skip, last_lnk, gid, lnk_op, op_data)) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_CANTNEXT, FAIL, "error iterating over links")
@@ -678,13 +729,13 @@ H5G_obj_info(H5O_loc_t *oloc, H5G_info_t *grp_info, hid_t dxpl_id)
     HDassert(grp_info);
 
     /* Attempt to get the link info for this group */
-    if(H5O_msg_read(oloc, H5O_LINFO_ID, &linfo, dxpl_id)) {
+    if(H5G_obj_get_linfo(oloc, &linfo, dxpl_id)) {
         /* Retrieve the information about the links */
         grp_info->nlinks = linfo.nlinks;
         grp_info->max_corder = linfo.max_corder;
 
         /* Check if the group is using compact or dense storage for its links */
-        if(H5F_addr_defined(linfo.link_fheap_addr))
+        if(H5F_addr_defined(linfo.fheap_addr))
             grp_info->storage_type = H5G_STORAGE_TYPE_DENSE;
         else
             grp_info->storage_type = H5G_STORAGE_TYPE_COMPACT;
@@ -734,7 +785,7 @@ H5G_obj_get_name_by_idx(H5O_loc_t *oloc, H5_index_t idx_type,
     HDassert(oloc && oloc->file);
 
     /* Attempt to get the link info for this group */
-    if(H5O_msg_read(oloc, H5O_LINFO_ID, &linfo, dxpl_id)) {
+    if(H5G_obj_get_linfo(oloc, &linfo, dxpl_id)) {
         /* Check for creation order tracking, if creation order index lookup requested */
         if(idx_type == H5_INDEX_CRT_ORDER) {
             /* Check if creation order is tracked */
@@ -743,7 +794,7 @@ H5G_obj_get_name_by_idx(H5O_loc_t *oloc, H5_index_t idx_type,
         } /* end if */
 
         /* Check for dense link storage */
-        if(H5F_addr_defined(linfo.link_fheap_addr)) {
+        if(H5F_addr_defined(linfo.fheap_addr)) {
             /* Get the object's name from the dense link storage */
             if((ret_value = H5G_dense_get_name_by_idx(oloc->file, dxpl_id, &linfo, idx_type, order, n, name, size)) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "can't locate name")
@@ -799,8 +850,8 @@ H5G_obj_get_type_by_idx(H5O_loc_t *oloc, hsize_t idx, hid_t dxpl_id)
     HDassert(oloc);
 
     /* Attempt to get the link info for this group */
-    if(H5O_msg_read(oloc, H5O_LINFO_ID, &linfo, dxpl_id)) {
-        if(H5F_addr_defined(linfo.link_fheap_addr)) {
+    if(H5G_obj_get_linfo(oloc, &linfo, dxpl_id)) {
+        if(H5F_addr_defined(linfo.fheap_addr)) {
             /* Get the object's name from the dense link storage */
             if((ret_value = H5G_dense_get_type_by_idx(oloc->file, dxpl_id, &linfo, idx)) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, H5G_UNKNOWN, "can't locate type")
@@ -857,7 +908,7 @@ H5G_obj_remove_update_linfo(H5O_loc_t *oloc, H5O_linfo_t *linfo, hid_t dxpl_id)
         linfo->max_corder = 0;
 
     /* Check for transitioning out of dense storage, if we are using it */
-    if(H5F_addr_defined(linfo->link_fheap_addr)) {
+    if(H5F_addr_defined(linfo->fheap_addr)) {
         /* Check if there's no more links */
         if(linfo->nlinks == 0) {
             /* Delete the dense storage */
@@ -961,12 +1012,12 @@ H5G_obj_remove(H5O_loc_t *oloc, H5RS_str_t *grp_full_path_r, const char *name, h
     HDassert(name && *name);
 
     /* Attempt to get the link info for this group */
-    if(H5O_msg_read(oloc, H5O_LINFO_ID, &linfo, dxpl_id)) {
+    if(H5G_obj_get_linfo(oloc, &linfo, dxpl_id)) {
         /* Using the new format for groups */
         use_old_format = FALSE;
 
         /* Check for dense or compact storage */
-        if(H5F_addr_defined(linfo.link_fheap_addr)) {
+        if(H5F_addr_defined(linfo.fheap_addr)) {
             /* Remove object from the dense link storage */
             if(H5G_dense_remove(oloc->file, dxpl_id, &linfo, grp_full_path_r, name) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "can't remove object")
@@ -1026,7 +1077,7 @@ H5G_obj_remove_by_idx(H5O_loc_t *grp_oloc, H5RS_str_t *grp_full_path_r,
     HDassert(grp_oloc && grp_oloc->file);
 
     /* Attempt to get the link info for this group */
-    if(H5O_msg_read(grp_oloc, H5O_LINFO_ID, &linfo, dxpl_id)) {
+    if(H5G_obj_get_linfo(grp_oloc, &linfo, dxpl_id)) {
         /* Check for creation order tracking, if creation order index lookup requested */
         if(idx_type == H5_INDEX_CRT_ORDER) {
             /* Check if creation order is tracked */
@@ -1038,7 +1089,7 @@ H5G_obj_remove_by_idx(H5O_loc_t *grp_oloc, H5RS_str_t *grp_full_path_r,
         use_old_format = FALSE;
 
         /* Check for dense or compact storage */
-        if(H5F_addr_defined(linfo.link_fheap_addr)) {
+        if(H5F_addr_defined(linfo.fheap_addr)) {
             /* Remove object from the dense link storage */
             if(H5G_dense_remove_by_idx(grp_oloc->file, dxpl_id, &linfo, grp_full_path_r, idx_type, order, n) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "can't remove object")
@@ -1103,9 +1154,9 @@ H5G_obj_lookup(H5O_loc_t *grp_oloc, const char *name, H5O_link_t *lnk,
     HDassert(name && *name);
 
     /* Attempt to get the link info message for this group */
-    if(H5O_msg_read(grp_oloc, H5O_LINFO_ID, &linfo, dxpl_id)) {
+    if(H5G_obj_get_linfo(grp_oloc, &linfo, dxpl_id)) {
         /* Check for dense link storage */
-        if(H5F_addr_defined(linfo.link_fheap_addr)) {
+        if(H5F_addr_defined(linfo.fheap_addr)) {
             /* Get the object's info from the dense link storage */
             if(H5G_dense_lookup(grp_oloc->file, dxpl_id, &linfo, name, lnk) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "can't locate object")
@@ -1157,7 +1208,7 @@ H5G_obj_lookup_by_idx(H5O_loc_t *grp_oloc, H5_index_t idx_type,
     HDassert(grp_oloc && grp_oloc->file);
 
     /* Attempt to get the link info message for this group */
-    if(H5O_msg_read(grp_oloc, H5O_LINFO_ID, &linfo, dxpl_id)) {
+    if(H5G_obj_get_linfo(grp_oloc, &linfo, dxpl_id)) {
         /* Check for creation order tracking, if creation order index lookup requested */
         if(idx_type == H5_INDEX_CRT_ORDER) {
             /* Check if creation order is tracked */
@@ -1166,7 +1217,7 @@ H5G_obj_lookup_by_idx(H5O_loc_t *grp_oloc, H5_index_t idx_type,
         } /* end if */
 
         /* Check for dense link storage */
-        if(H5F_addr_defined(linfo.link_fheap_addr)) {
+        if(H5F_addr_defined(linfo.fheap_addr)) {
             /* Get the link from the dense storage */
             if(H5G_dense_lookup_by_idx(grp_oloc->file, dxpl_id, &linfo, idx_type, order, n, lnk) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_NOTFOUND, FAIL, "can't locate object")
diff --git a/src/H5Gpkg.h b/src/H5Gpkg.h
index 181d5e4..879b364 100644
--- a/src/H5Gpkg.h
+++ b/src/H5Gpkg.h
@@ -376,12 +376,12 @@ H5_DLL herr_t H5G_traverse(const H5G_loc_t *loc, const char *name,
 H5_DLL herr_t H5G_stab_create(H5O_loc_t *grp_oloc, hid_t dxpl_id,
     const H5O_ginfo_t *ginfo, H5O_stab_t *stab);
 H5_DLL herr_t H5G_stab_create_components(H5F_t *f, H5O_stab_t *stab, size_t size_hint, hid_t dxpl_id);
-H5_DLL herr_t H5G_stab_insert(H5O_loc_t *grp_oloc, const char *name,
+H5_DLL herr_t H5G_stab_insert(const H5O_loc_t *grp_oloc, const char *name,
     H5O_link_t *obj_lnk, hid_t dxpl_id);
 H5_DLL herr_t H5G_stab_insert_real(H5F_t *f, H5O_stab_t *stab, const char *name,
     H5O_link_t *obj_lnk, hid_t dxpl_id);
 H5_DLL herr_t H5G_stab_delete(H5F_t *f, hid_t dxpl_id, const H5O_stab_t *stab);
-H5_DLL herr_t H5G_stab_iterate(H5O_loc_t *oloc, hid_t dxpl_id,
+H5_DLL herr_t H5G_stab_iterate(const H5O_loc_t *oloc, hid_t dxpl_id,
     H5_iter_order_t order, hsize_t skip, hsize_t *last_lnk, hid_t gid,
     H5G_link_iterate_t *lnk_op, void *op_data);
 H5_DLL herr_t H5G_stab_count(struct H5O_loc_t *oloc, hsize_t *num_objs, hid_t dxpl_id);
@@ -453,7 +453,7 @@ H5_DLL herr_t H5G_link_name_replace(H5F_t *file, hid_t dxpl_id,
     haddr_t lnk_addr);
 
 /* Functions that understand "compact" link storage */
-H5_DLL herr_t H5G_compact_insert(H5O_loc_t *grp_oloc, H5O_link_t *obj_lnk,
+H5_DLL herr_t H5G_compact_insert(const H5O_loc_t *grp_oloc, H5O_link_t *obj_lnk,
     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, H5_index_t idx_type, H5_iter_order_t order,
@@ -504,7 +504,9 @@ H5_DLL herr_t H5G_dense_delete(H5F_t *f, hid_t dxpl_id, H5O_linfo_t *linfo,
 /* 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, hid_t gcpl_id, H5O_loc_t *oloc/*out*/);
-H5_DLL herr_t H5G_obj_insert(H5O_loc_t *grp_oloc, const char *name,
+H5_DLL H5O_linfo_t * H5G_obj_get_linfo(const H5O_loc_t *grp_oloc,
+    H5O_linfo_t *linfo, hid_t dxpl_id);
+H5_DLL herr_t H5G_obj_insert(const H5O_loc_t *grp_oloc, const char *name,
     H5O_link_t *obj_lnk, hbool_t adj_link, hid_t dxpl_id);
 H5_DLL herr_t H5G_obj_iterate(hid_t loc_id, const char *group_name,
     H5_index_t idx_type, H5_iter_order_t order, hsize_t skip, hsize_t *last_obj,
diff --git a/src/H5Gstab.c b/src/H5Gstab.c
index e174072..431571b 100644
--- a/src/H5Gstab.c
+++ b/src/H5Gstab.c
@@ -255,7 +255,7 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5G_stab_insert(H5O_loc_t *grp_oloc, const char *name, H5O_link_t *obj_lnk,
+H5G_stab_insert(const H5O_loc_t *grp_oloc, const char *name, H5O_link_t *obj_lnk,
     hid_t dxpl_id)
 {
     H5O_stab_t		stab;		/* Symbol table message		*/
@@ -433,7 +433,7 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5G_stab_iterate(H5O_loc_t *oloc, hid_t dxpl_id, H5_iter_order_t order,
+H5G_stab_iterate(const H5O_loc_t *oloc, hid_t dxpl_id, H5_iter_order_t order,
     hsize_t skip, hsize_t *last_lnk, hid_t gid,
     H5G_link_iterate_t *lnk_op, void *op_data)
 {
diff --git a/src/H5Gtest.c b/src/H5Gtest.c
index b0b4d52..2921bf0 100644
--- a/src/H5Gtest.c
+++ b/src/H5Gtest.c
@@ -133,11 +133,11 @@ H5G_is_empty_test(hid_t gid)
             HGOTO_ERROR(H5E_SYM, H5E_BADVALUE, FAIL, "both symbol table and link info messages found")
 
         /* Get the link info */
-        if(NULL == H5O_msg_read(&(grp->oloc), H5O_LINFO_ID, &linfo, H5AC_dxpl_id))
+        if(NULL == H5G_obj_get_linfo(&(grp->oloc), &linfo, H5AC_dxpl_id))
             HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "can't get link info")
 
         /* Check for 'dense' link storage file addresses being defined */
-        if(H5F_addr_defined(linfo.link_fheap_addr))
+        if(H5F_addr_defined(linfo.fheap_addr))
             HGOTO_DONE(FALSE)
         if(H5F_addr_defined(linfo.name_bt2_addr))
             HGOTO_DONE(FALSE)
@@ -343,11 +343,11 @@ H5G_is_new_dense_test(hid_t gid)
         H5O_linfo_t linfo;		/* Link info message */
 
         /* Get the link info */
-        if(NULL == H5O_msg_read(&(grp->oloc), H5O_LINFO_ID, &linfo, H5AC_dxpl_id))
+        if(NULL == H5G_obj_get_linfo(&(grp->oloc), &linfo, H5AC_dxpl_id))
             HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "can't get link info")
 
         /* Check for 'dense' link storage file addresses being defined */
-        if(!H5F_addr_defined(linfo.link_fheap_addr))
+        if(!H5F_addr_defined(linfo.fheap_addr))
             HGOTO_DONE(FALSE)
         if(!H5F_addr_defined(linfo.name_bt2_addr))
             HGOTO_DONE(FALSE)
@@ -393,11 +393,11 @@ H5G_new_dense_info_test(hid_t gid, hsize_t *name_count, hsize_t *corder_count)
         HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a group")
 
     /* Get the link info */
-    if(NULL == H5O_msg_read(&(grp->oloc), H5O_LINFO_ID, &linfo, H5AC_dxpl_id))
+    if(NULL == H5G_obj_get_linfo(&(grp->oloc), &linfo, H5AC_dxpl_id))
         HGOTO_ERROR(H5E_SYM, H5E_BADMESG, FAIL, "can't get link info")
 
     /* Check for 'dense' link storage file addresses being defined */
-    if(!H5F_addr_defined(linfo.link_fheap_addr))
+    if(!H5F_addr_defined(linfo.fheap_addr))
         HGOTO_DONE(FAIL)
     if(!H5F_addr_defined(linfo.name_bt2_addr))
         HGOTO_DONE(FAIL)
diff --git a/src/H5Gtraverse.c b/src/H5Gtraverse.c
index 255059c..9434f17 100644
--- a/src/H5Gtraverse.c
+++ b/src/H5Gtraverse.c
@@ -714,7 +714,7 @@ H5G_traverse_real(const H5G_loc_t *_loc, const char *name, unsigned target,
 
                 /* Get the link info for parent group */
                 /* (OK if not found) */
-                if(NULL == H5O_msg_read(grp_loc.oloc, H5O_LINFO_ID, &par_linfo, dxpl_id)) {
+                if(NULL == H5G_obj_get_linfo(grp_loc.oloc, &par_linfo, dxpl_id)) {
                     /* Clear error stack from not finding the link info message */
                     H5E_clear_stack(NULL);
 
diff --git a/src/H5O.c b/src/H5O.c
index 5f3e507..f02a7f5 100644
--- a/src/H5O.c
+++ b/src/H5O.c
@@ -2046,3 +2046,43 @@ done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5O_get_create_plist() */
 
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_nlinks
+ *
+ * Purpose:	Retrieve the number of link messages read in from the file
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *		March 11 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_get_nlinks(const H5O_loc_t *oloc, hid_t dxpl_id, hsize_t *nlinks)
+{
+    H5O_t *oh = NULL;                   /* Object header */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(H5O_get_nlinks, FAIL)
+
+    /* Check args */
+    HDassert(oloc);
+    HDassert(nlinks);
+
+    /* Get the object header */
+    if(NULL == (oh = H5AC_protect(oloc->file, dxpl_id, H5AC_OHDR, oloc->addr, NULL, NULL, H5AC_READ)))
+	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header")
+
+    /* Retrieve the # of link messages seen when the object header was loaded */
+    *nlinks = oh->link_msgs_seen;
+
+done:
+    if(oh && H5AC_unprotect(oloc->file, dxpl_id, H5AC_OHDR, oloc->addr, oh, H5AC__NO_FLAGS_SET) < 0)
+	HDONE_ERROR(H5E_OHDR, H5E_PROTECT, FAIL, "unable to release object header")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5O_get_nlinks() */
+
diff --git a/src/H5Ocache.c b/src/H5Ocache.c
index 2a76526..774055a 100644
--- a/src/H5Ocache.c
+++ b/src/H5Ocache.c
@@ -606,6 +606,11 @@ H5O_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, const void UNUSED * _udata1,
                 oh->has_refcount_msg = TRUE;
                 oh->nlink = *refcount;
             } /* end if */
+            /* Check if next message to examine is a link message */
+            else if(H5O_LINK_ID == oh->mesg[curmesg].type->id) {
+                /* Increment the count of link messages */
+                oh->link_msgs_seen++;
+            } /* end if */
         } /* end for */
     } /* end while */
 
diff --git a/src/H5Ocopy.c b/src/H5Ocopy.c
index ec51f00..748d780 100644
--- a/src/H5Ocopy.c
+++ b/src/H5Ocopy.c
@@ -342,6 +342,7 @@ H5O_copy_header_real(const H5O_loc_t *oloc_src, H5O_loc_t *oloc_dst /*out */,
     oh_dst->version = oh_src->version;
     oh_dst->flags = oh_src->flags;
     oh_dst->skipped_mesg_size = oh_src->skipped_mesg_size;
+    oh_dst->link_msgs_seen = oh_src->link_msgs_seen;
     oh_dst->sizeof_size = H5F_SIZEOF_SIZE(oloc_dst->file);
     oh_dst->sizeof_addr = H5F_SIZEOF_ADDR(oloc_dst->file);
 
diff --git a/src/H5Olinfo.c b/src/H5Olinfo.c
index 0a2e145..eade420 100644
--- a/src/H5Olinfo.c
+++ b/src/H5Olinfo.c
@@ -137,8 +137,8 @@ H5O_linfo_decode(H5F_t *f, hid_t UNUSED dxpl_id, unsigned UNUSED mesg_flags,
     linfo->track_corder = (index_flags & H5O_LINFO_TRACK_CORDER) ? TRUE : FALSE;
     linfo->index_corder = (index_flags & H5O_LINFO_INDEX_CORDER) ? TRUE : FALSE;
 
-    /* Number of links in the group */
-    H5F_DECODE_LENGTH(f, p, linfo->nlinks)
+    /* Set the number of links in the group to an invalid value, so we query it later */
+    linfo->nlinks = HSIZET_MAX;
 
     /* Max. link creation order value for the group, if tracked */
     if(linfo->track_corder)
@@ -147,7 +147,7 @@ H5O_linfo_decode(H5F_t *f, hid_t UNUSED dxpl_id, unsigned UNUSED mesg_flags,
         linfo->max_corder = 0;
 
     /* Address of fractal heap to store "dense" links */
-    H5F_addr_decode(f, &p, &(linfo->link_fheap_addr));
+    H5F_addr_decode(f, &p, &(linfo->fheap_addr));
 
     /* Address of v2 B-tree to index names of links (names are always indexed) */
     H5F_addr_decode(f, &p, &(linfo->name_bt2_addr));
@@ -204,15 +204,12 @@ H5O_linfo_encode(H5F_t *f, hbool_t UNUSED disable_shared, uint8_t *p, const void
     index_flags |= linfo->index_corder ? H5O_LINFO_INDEX_CORDER : 0;
     *p++ = index_flags;
 
-    /* Number of links in the group */
-    H5F_ENCODE_LENGTH(f, p, linfo->nlinks)
-
     /* Max. link creation order value for the group, if tracked */
     if(linfo->track_corder)
         INT64ENCODE(p, linfo->max_corder)
 
     /* Address of fractal heap to store "dense" links */
-    H5F_addr_encode(f, &p, linfo->link_fheap_addr);
+    H5F_addr_encode(f, &p, linfo->fheap_addr);
 
     /* Address of v2 B-tree to index names of links */
     H5F_addr_encode(f, &p, linfo->name_bt2_addr);
@@ -294,7 +291,6 @@ H5O_linfo_size(const H5F_t *f, hbool_t UNUSED disable_shared, const void *_mesg)
     /* Set return value */
     ret_value = 1                       /* Version */
                 + 1                     /* Index flags */
-                + H5F_SIZEOF_SIZE(f)    /* Number of links */
                 + (linfo->track_corder ? 8 : 0) /* Curr. max. creation order value */
                 + H5F_SIZEOF_ADDR(f)    /* Address of fractal heap to store "dense" links */
                 + H5F_SIZEOF_ADDR(f)    /* Address of v2 B-tree for indexing names of links */
@@ -354,7 +350,7 @@ H5O_linfo_delete(H5F_t *f, hid_t dxpl_id, const void *_mesg)
     HDassert(linfo);
 
     /* If the group is using "dense" link storage, delete it */
-    if(H5F_addr_defined(linfo->link_fheap_addr))
+    if(H5F_addr_defined(linfo->fheap_addr))
         if(H5G_dense_delete(f, dxpl_id, (H5O_linfo_t *)linfo, TRUE) < 0)   /* Casting away const OK - QAK */
             HGOTO_ERROR(H5E_OHDR, H5E_CANTFREE, FAIL, "unable to free dense link storage")
 
@@ -402,7 +398,7 @@ H5O_linfo_copy_file(H5F_t UNUSED *file_src, void *native_src, H5F_t *file_dst,
     if(cpy_info->max_depth >= 0 && cpy_info->curr_depth >= cpy_info->max_depth) {
         linfo_dst->nlinks = 0;
         linfo_dst->max_corder = 0;
-        linfo_dst->link_fheap_addr = HADDR_UNDEF;
+        linfo_dst->fheap_addr = HADDR_UNDEF;
         linfo_dst->name_bt2_addr = HADDR_UNDEF;
         linfo_dst->corder_bt2_addr = HADDR_UNDEF;
     } /* end if */
@@ -411,7 +407,7 @@ H5O_linfo_copy_file(H5F_t UNUSED *file_src, void *native_src, H5F_t *file_dst,
         /* (XXX: should probably get the "creation" parameters for the source group's
          *      dense link storage components and use those - QAK)
          */
-        if(H5F_addr_defined(linfo_src->link_fheap_addr)) {
+        if(H5F_addr_defined(linfo_src->fheap_addr)) {
             if(H5G_dense_create(file_dst, dxpl_id, linfo_dst) < 0)
                 HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, NULL, "unable to create 'dense' form of new format group")
         } /* end if */
@@ -513,7 +509,7 @@ H5O_linfo_post_copy_file(const H5O_loc_t *src_oloc, const void *mesg_src,
         HGOTO_DONE(SUCCEED)
 
     /* Check for copying dense link storage */
-    if(H5F_addr_defined(linfo_src->link_fheap_addr)) {
+    if(H5F_addr_defined(linfo_src->fheap_addr)) {
         H5O_linfo_postcopy_ud_t udata;          /* User data for iteration callback */
         H5G_link_iterate_t lnk_op;              /* Link operator */
 
@@ -575,7 +571,7 @@ H5O_linfo_debug(H5F_t UNUSED *f, hid_t UNUSED dxpl_id, const void *_mesg, FILE *
     HDfprintf(stream, "%*s%-*s %Hd\n", indent, "", fwidth,
 	      "Max. creation order value:", linfo->max_corder);
     HDfprintf(stream, "%*s%-*s %a\n", indent, "", fwidth,
-	      "'Dense' link storage fractal heap address:", linfo->link_fheap_addr);
+	      "'Dense' link storage fractal heap address:", linfo->fheap_addr);
     HDfprintf(stream, "%*s%-*s %a\n", indent, "", fwidth,
 	      "'Dense' link storage name index v2 B-tree address:", linfo->name_bt2_addr);
     HDfprintf(stream, "%*s%-*s %a\n", indent, "", fwidth,
diff --git a/src/H5Omessage.c b/src/H5Omessage.c
index 651cd64..a8b332b 100644
--- a/src/H5Omessage.c
+++ b/src/H5Omessage.c
@@ -908,7 +908,7 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5O_msg_remove(H5O_loc_t *loc, unsigned type_id, int sequence, hbool_t adj_link,
+H5O_msg_remove(const H5O_loc_t *loc, unsigned type_id, int sequence, hbool_t adj_link,
     hid_t dxpl_id)
 {
     H5O_t *oh = NULL;                   /* Pointer to actual object header */
diff --git a/src/H5Opkg.h b/src/H5Opkg.h
index 68a286d..3df402f 100644
--- a/src/H5Opkg.h
+++ b/src/H5Opkg.h
@@ -266,6 +266,7 @@ struct H5O_t {
     size_t	alloc_nmesgs;		/*number of message slots	     */
     H5O_mesg_t	*mesg;			/*array of messages		     */
     size_t      skipped_mesg_size;      /*size of skipped messages (for sanity checking) */
+    size_t      link_msgs_seen;         /* # of link messages seen when loading header */
 
     /* Chunk management (not stored) */
     size_t	nchunks;		/*number of chunks		     */
diff --git a/src/H5Oprivate.h b/src/H5Oprivate.h
index 60d7a1d..2bfe8ef 100644
--- a/src/H5Oprivate.h
+++ b/src/H5Oprivate.h
@@ -187,7 +187,7 @@ typedef struct H5O_linfo_t {
 
     /* Storage management info */
     hsize_t     nlinks;                 /* Number of links in the group      */
-    haddr_t     link_fheap_addr;        /* Address of fractal heap for storing "dense" links */
+    haddr_t     fheap_addr;             /* Address of fractal heap for storing "dense" links */
     haddr_t     name_bt2_addr;          /* Address of v2 B-tree for indexing names of links */
 } H5O_linfo_t;
 
@@ -466,6 +466,7 @@ H5_DLL herr_t H5O_get_info(H5O_loc_t *oloc, H5O_info_t *oinfo, hid_t dxpl_id);
 H5_DLL herr_t H5O_obj_type(const H5O_loc_t *loc, H5O_type_t *obj_type, hid_t dxpl_id);
 H5_DLL herr_t H5O_get_create_plist(const H5O_loc_t *loc, hid_t dxpl_id, struct H5P_genplist_t *oc_plist);
 H5_DLL hid_t H5O_open_name(H5G_loc_t *loc, const char *name, hid_t lapl_id);
+H5_DLL herr_t H5O_get_nlinks(const H5O_loc_t *loc, hid_t dxpl_id, hsize_t *nlinks);
 
 /* Object header message routines */
 H5_DLL herr_t H5O_msg_create(const H5O_loc_t *loc, unsigned type_id, unsigned mesg_flags,
@@ -481,7 +482,7 @@ H5_DLL void *H5O_msg_free(unsigned type_id, void *mesg);
 H5_DLL void *H5O_msg_copy(unsigned type_id, const void *mesg, void *dst);
 H5_DLL int H5O_msg_count(const H5O_loc_t *loc, unsigned type_id, hid_t dxpl_id);
 H5_DLL htri_t H5O_msg_exists(H5O_loc_t *loc, unsigned type_id, hid_t dxpl_id);
-H5_DLL herr_t H5O_msg_remove(H5O_loc_t *loc, unsigned type_id, int sequence,
+H5_DLL herr_t H5O_msg_remove(const H5O_loc_t *loc, unsigned type_id, int sequence,
     hbool_t adj_link, hid_t dxpl_id);
 H5_DLL herr_t H5O_msg_remove_op(const H5O_loc_t *loc, unsigned type_id, int sequence,
     H5O_operator_t op, void *op_data, hbool_t adj_link, hid_t dxpl_id);
diff --git a/src/H5Orefcount.c b/src/H5Orefcount.c
index 8f49b8c..85ff4c0 100644
--- a/src/H5Orefcount.c
+++ b/src/H5Orefcount.c
@@ -215,9 +215,9 @@ done:
  *-------------------------------------------------------------------------
  */
 static size_t
-H5O_refcount_size(const H5F_t *f, hbool_t UNUSED disable_shared, const void *_mesg)
+H5O_refcount_size(const H5F_t UNUSED *f, hbool_t UNUSED disable_shared,
+    const void UNUSED *_mesg)
 {
-    const H5O_refcount_t   *refcount = (const H5O_refcount_t *)_mesg;
     size_t ret_value;   /* Return value */
 
     FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5O_refcount_size)