[svn-r13104] Description:

    Add support for renaming compact & dense/shared & non-shared attributes in 
all cases.

Tested on:
    Linux/32 2.6 (chicago)
    Linux/64 2.6 (chicago2)

7 files changed, 205 insertions, 115 deletions

diff --git a/src/H5A.c b/src/H5A.c
index 6021c21..e10dd39 100644
--- a/src/H5A.c
+++ b/src/H5A.c
@@ -331,7 +331,7 @@ H5A_create(const H5G_loc_t *loc, const char *name, const H5T_t *type,
         H5P_genplist_t  *ac_plist;      /* ACPL Property list */
 
         /* Get a local copy of the attribute creation property list */
-        if(NULL == (ac_plist = H5I_object(acpl_id)))
+        if(NULL == (ac_plist = (H5P_genplist_t *)H5I_object(acpl_id)))
             HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list")
 
         if(H5P_get(ac_plist, H5P_STRCRT_CHAR_ENCODING_NAME, &(attr->encoding)) < 0)
@@ -1142,15 +1142,15 @@ H5Aget_create_plist(hid_t attr_id)
     HDassert(H5P_LST_ATTRIBUTE_CREATE_g != -1);
 
     /* Get attribute and default attribute creation property list*/
-    if(NULL == (attr = H5I_object_verify(attr_id, H5I_ATTR)))
+    if(NULL == (attr = (H5A_t *)H5I_object_verify(attr_id, H5I_ATTR)))
 	HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not an attribute")
-    if(NULL == (plist = H5I_object(H5P_LST_ATTRIBUTE_CREATE_g)))
+    if(NULL == (plist = (H5P_genplist_t *)H5I_object(H5P_LST_ATTRIBUTE_CREATE_g)))
         HGOTO_ERROR(H5E_PLIST, H5E_BADTYPE, FAIL, "can't get default ACPL")
 
     /* Create the property list object to return */
     if((new_plist_id = H5P_copy_plist(plist)) < 0)
 	HGOTO_ERROR(H5E_PLIST, H5E_CANTINIT, FAIL, "unable to copy attribute creation properties")
-    if(NULL == (new_plist = H5I_object(new_plist_id)))
+    if(NULL == (new_plist = (H5P_genplist_t *)H5I_object(new_plist_id)))
         HGOTO_ERROR(H5E_PLIST, H5E_BADTYPE, FAIL, "can't get property list")
 
     /* Set the character encoding on the new property list */
diff --git a/src/H5Abtree2.c b/src/H5Abtree2.c
index dc2478e..5fb37fe 100644
--- a/src/H5Abtree2.c
+++ b/src/H5Abtree2.c
@@ -36,6 +36,7 @@
 #include "H5private.h"		/* Generic Functions			*/
 #include "H5Apkg.h"		/* Attributes	  			*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
+#include "H5SMprivate.h"	/* Shared object header messages        */
 
 
 /****************/
@@ -56,6 +57,7 @@ typedef struct H5A_fh_ud_cmp_t {
     H5F_t       *f;                     /* Pointer to file that fractal heap is in */
     hid_t       dxpl_id;                /* DXPL for operation                */
     const char  *name;                  /* Name of attribute to compare      */
+    const H5A_dense_bt2_name_rec_t *record;     /* v2 B-tree record for attribute */
     H5B2_found_t found_op;              /* Callback when correct attribute is found */
     void        *found_op_data;         /* Callback data when correct attribute is found */
 
@@ -141,16 +143,22 @@ H5A_dense_fh_name_cmp(const void *obj, size_t UNUSED obj_len, void *_udata)
     FUNC_ENTER_NOAPI_NOINIT(H5A_dense_fh_name_cmp)
 
     /* Decode link information */
-    if(NULL == (attr = H5O_msg_decode(udata->f, udata->dxpl_id, H5O_ATTR_ID, obj)))
+    if(NULL == (attr = (H5A_t *)H5O_msg_decode(udata->f, udata->dxpl_id, H5O_ATTR_ID, (const unsigned char *)obj)))
         HGOTO_ERROR(H5E_OHDR, H5E_CANTDECODE, FAIL, "can't decode attribute")
 
     /* Compare the string values */
     udata->cmp = HDstrcmp(udata->name, attr->name);
 
     /* Check for correct attribute & callback to make */
-    if(udata->cmp == 0 && udata->found_op)
+    if(udata->cmp == 0 && udata->found_op) {
+        /* Check whether we should "reconstitute" the shared message info */
+        if(udata->record->flags & H5O_MSG_FLAG_SHARED)
+            H5SM_reconstitute(&(attr->sh_loc), udata->record->id);
+
+        /* Make callback */
         if((udata->found_op)(attr, udata->found_op_data) < 0)
             HGOTO_ERROR(H5E_OHDR, H5E_CANTOPERATE, FAIL, "attribute found callback failed")
+    } /* end if */
 
 done:
     /* Release the space allocated for the attrbute */
@@ -260,6 +268,7 @@ H5A_dense_btree2_name_compare(const void *_bt2_udata, const void *_bt2_rec)
         fh_udata.f = bt2_udata->f;
         fh_udata.dxpl_id = bt2_udata->dxpl_id;
         fh_udata.name = bt2_udata->name;
+        fh_udata.record = bt2_rec;
         fh_udata.found_op = bt2_udata->found_op;
         fh_udata.found_op_data = bt2_udata->found_op_data;
 
diff --git a/src/H5Adense.c b/src/H5Adense.c
index f47f9c0..9d9746a 100644
--- a/src/H5Adense.c
+++ b/src/H5Adense.c
@@ -75,7 +75,7 @@
 
 /*
  * Data exchange structure for dense attribute storage.  This structure is
- * passed through the v2 B-tree layer when modifying attributes.
+ * passed through the v2 B-tree layer when modifying the attribute data value.
  */
 typedef struct H5A_bt2_od_wrt_t {
     /* downward */
@@ -117,6 +117,7 @@ typedef struct {
     /* downward (internal) */
     H5F_t       *f;                     /* Pointer to file that fractal heap is in */
     hid_t       dxpl_id;                /* DXPL for operation                */
+    const H5A_dense_bt2_name_rec_t *record;     /* v2 B-tree record for attribute */
 
     /* upward */
     H5A_t  *attr;                       /* Copy of attribute                 */
@@ -264,7 +265,7 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5A_dense_open_cb
+ * Function:	H5A_dense_fnd_cb
  *
  * Purpose:	Callback when an attribute is located in an index
  *
@@ -277,13 +278,13 @@ done:
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5A_dense_open_cb(const void *_attr, void *_user_attr)
+H5A_dense_fnd_cb(const void *_attr, void *_user_attr)
 {
     const H5A_t *attr = (const H5A_t *)_attr; /* Record from B-tree */
     H5A_t **user_attr = (H5A_t **)_user_attr; /* User data from v2 B-tree attribute lookup */
     herr_t ret_value = SUCCEED;         /* Return value */
 
-    FUNC_ENTER_NOAPI_NOINIT(H5A_dense_open_cb)
+    FUNC_ENTER_NOAPI_NOINIT(H5A_dense_fnd_cb)
 
     /*
      * Check arguments.
@@ -297,7 +298,7 @@ H5A_dense_open_cb(const void *_attr, void *_user_attr)
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5A_dense_open_cb() */
+} /* end H5A_dense_fnd_cb() */
 
 
 /*-------------------------------------------------------------------------
@@ -361,7 +362,7 @@ H5A_dense_open(H5F_t *f, hid_t dxpl_id, const H5O_t *oh, const char *name)
     udata.name_hash = H5_checksum_lookup3(name, HDstrlen(name), 0);
     udata.flags = 0;
     udata.corder = -1;   /* XXX: None yet */
-    udata.found_op = H5A_dense_open_cb;       /* v2 B-tree comparison callback */
+    udata.found_op = H5A_dense_fnd_cb;       /* v2 B-tree comparison callback */
     udata.found_op_data = &ret_value;
 
     /* Find & copy the attribute in the 'name' index */
@@ -720,12 +721,123 @@ H5A_dense_copy_fh_cb(const void *obj, size_t UNUSED obj_len, void *_udata)
     if(NULL == (udata->attr = (H5A_t *)H5O_msg_decode(udata->f, udata->dxpl_id, H5O_ATTR_ID, (const unsigned char *)obj)))
         HGOTO_ERROR(H5E_ATTR, H5E_CANTDECODE, FAIL, "can't decode attribute")
 
+    /* Check whether we should "reconstitute" the shared message info */
+    if(udata->record->flags & H5O_MSG_FLAG_SHARED)
+        H5SM_reconstitute(&(udata->attr->sh_loc), udata->record->id);
+
 done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5A_dense_copy_fh_cb() */
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5A_dense_rename
+ *
+ * Purpose:	Rename an attribute in dense storage structures for an object
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Jan  3 2007
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5A_dense_rename(H5F_t *f, hid_t dxpl_id, const H5O_t *oh, const char *old_name,
+    const char *new_name)
+{
+    H5A_bt2_ud_common_t udata;          /* User data for v2 B-tree modify */
+    H5HF_t *fheap = NULL;               /* Fractal heap handle */
+    H5HF_t *shared_fheap = NULL;        /* Fractal heap handle for shared header messages */
+    H5A_t *attr_copy = NULL;            /* Copy of attribute to rename */
+    htri_t attr_sharable;               /* Flag indicating attributes are sharable */
+    unsigned mesg_flags = 0;            /* Flags for storing message */
+    htri_t shared_mesg;                 /* Should this message be stored in the Shared Message table? */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(H5A_dense_rename, FAIL)
+
+    /*
+     * Check arguments.
+     */
+    HDassert(f);
+    HDassert(oh);
+    HDassert(old_name);
+    HDassert(new_name);
+
+    /* Check if attributes are shared in this file */
+    if((attr_sharable = H5SM_type_shared(f, H5O_ATTR_ID, dxpl_id)) < 0)
+        HGOTO_ERROR(H5E_ATTR, H5E_CANTGET, FAIL, "can't determine if attributes are shared")
+
+    /* Get handle for shared object heap, if attributes are sharable */
+    if(attr_sharable) {
+        haddr_t shared_fheap_addr;      /* Address of fractal heap to use */
+
+        /* Retrieve the address of the shared object's fractal heap */
+        if(HADDR_UNDEF == (shared_fheap_addr = H5SM_get_fheap_addr(f, H5O_ATTR_ID, dxpl_id)))
+            HGOTO_ERROR(H5E_ATTR, H5E_CANTGET, FAIL, "can't get shared object heap address")
+
+        /* Open the fractal heap for shared header messages */
+        if(NULL == (shared_fheap = H5HF_open(f, dxpl_id, shared_fheap_addr)))
+            HGOTO_ERROR(H5E_ATTR, H5E_CANTOPENOBJ, FAIL, "unable to open fractal heap")
+    } /* end if */
+
+    /* Open the fractal heap */
+    if(NULL == (fheap = H5HF_open(f, dxpl_id, oh->attr_fheap_addr)))
+        HGOTO_ERROR(H5E_ATTR, H5E_CANTOPENOBJ, FAIL, "unable to open fractal heap")
+
+    /* Create the "udata" information for v2 B-tree record modify */
+    udata.f = f;
+    udata.dxpl_id = dxpl_id;
+    udata.fheap = fheap;
+    udata.shared_fheap = shared_fheap;
+    udata.name = old_name;
+    udata.name_hash = H5_checksum_lookup3(old_name, HDstrlen(old_name), 0);
+    udata.flags = 0;
+    udata.corder = -1;   /* XXX: None yet */
+    udata.found_op = H5A_dense_fnd_cb;       /* v2 B-tree comparison callback */
+    udata.found_op_data = &attr_copy;
+
+    /* Get copy of attribute through 'name' tracking v2 B-tree */
+    if(H5B2_find(f, dxpl_id, H5A_BT2_NAME, oh->name_bt2_addr, &udata, NULL, NULL) < 0)
+        HGOTO_ERROR(H5E_ATTR, H5E_CANTINSERT, FAIL, "unable to find record in v2 B-tree")
+    HDassert(attr_copy);
+
+    /* Change name of attribute */
+    H5MM_xfree(attr_copy->name);
+    attr_copy->name = H5MM_xstrdup(new_name);
+
+    /* Should this attribute be written as a SOHM? */
+    /* (allows for attributes that change "shared" status) */
+    if((shared_mesg = H5SM_try_share(f, dxpl_id, H5O_ATTR_ID, attr_copy)) > 0)
+        /* Mark the message as shared */
+        mesg_flags |= H5O_MSG_FLAG_SHARED;
+    else if(shared_mesg < 0)
+	HGOTO_ERROR(H5E_ATTR, H5E_WRITEERROR, FAIL, "error determining if message should be shared")
+
+    /* Insert renamed attribute back into dense storage */
+    if(H5A_dense_insert(f, dxpl_id, oh, mesg_flags, attr_copy) < 0)
+        HGOTO_ERROR(H5E_ATTR, H5E_CANTINSERT, FAIL, "unable to add to dense storage")
+
+    /* Delete old attribute from dense storage */
+    if(H5A_dense_remove(f, dxpl_id, oh, old_name) < 0)
+        HGOTO_ERROR(H5E_ATTR, H5E_CANTDELETE, FAIL, "unable to delete attribute in dense storage")
+
+done:
+    /* Release resources */
+    if(shared_fheap && H5HF_close(shared_fheap, dxpl_id) < 0)
+        HDONE_ERROR(H5E_ATTR, H5E_CLOSEERROR, FAIL, "can't close fractal heap")
+    if(fheap && H5HF_close(fheap, dxpl_id) < 0)
+        HDONE_ERROR(H5E_ATTR, H5E_CLOSEERROR, FAIL, "can't close fractal heap")
+    if(attr_copy)
+        H5O_msg_free(H5O_ATTR_ID, attr_copy);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5A_dense_write() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5A_dense_iterate_bt2_cb
  *
  * Purpose:	v2 B-tree callback for dense attribute storage iterator
@@ -764,16 +876,14 @@ H5A_dense_iterate_bt2_cb(const void *_record, void *_bt2_udata)
         /* down */
         fh_udata.f = bt2_udata->f;
         fh_udata.dxpl_id = bt2_udata->dxpl_id;
+        fh_udata.record = record;
+        fh_udata.attr = NULL;
 
         /* Call fractal heap 'op' routine, to copy the attribute information */
         if(H5HF_op(fheap, bt2_udata->dxpl_id, record->id,
                 H5A_dense_copy_fh_cb, &fh_udata) < 0)
             HGOTO_ERROR(H5E_ATTR, H5E_CANTOPERATE, H5_ITER_ERROR, "heap op callback failed")
 
-        /* Check whether we should "reconstitute" the shared message info */
-        if(record->flags & H5O_MSG_FLAG_SHARED)
-            H5SM_reconstitute(&(fh_udata.attr->sh_loc), record->id);
-
         /* Check which type of callback to make */
         switch(bt2_udata->attr_op->op_type) {
             case H5A_ATTR_OP_APP:
@@ -922,46 +1032,6 @@ done:
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5A_dense_remove_fh_cb
- *
- * Purpose:	Callback for fractal heap operator when removing attributes
- *
- * Return:	SUCCEED/FAIL
- *
- * Programmer:	Quincey Koziol
- *		koziol@hdfgroup.org
- *		Dec 11 2006
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5A_dense_remove_fh_cb(const void *obj, size_t UNUSED obj_len, void *_udata)
-{
-    H5A_fh_ud_rm_t *udata = (H5A_fh_ud_rm_t *)_udata;       /* User data for fractal heap 'op' callback */
-    H5A_t *attr = NULL;                 /* Pointer to attribute created from heap object */
-    herr_t ret_value = SUCCEED;         /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT(H5A_dense_remove_fh_cb)
-
-    /* Decode attribute */
-    if(NULL == (attr = (H5A_t *)H5O_msg_decode(udata->f, udata->dxpl_id, H5O_ATTR_ID, (const unsigned char *)obj)))
-        HGOTO_ERROR(H5E_ATTR, H5E_CANTDECODE, FAIL, "can't decode attribute")
-
-    /* Perform the deletion action on the attribute */
-    /* (takes care of shared & committed datatype/dataspace components) */
-    if(H5O_attr_delete(udata->f, udata->dxpl_id, attr, TRUE) < 0)
-        HGOTO_ERROR(H5E_ATTR, H5E_CANTDELETE, FAIL, "unable to delete attribute")
-
-done:
-    /* Release the space allocated for the message */
-    if(attr)
-        H5O_msg_free_real(H5O_MSG_ATTR, attr);
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5A_dense_remove_fh_cb() */
-
-
-/*-------------------------------------------------------------------------
  * Function:	H5A_dense_remove_bt2_cb
  *
  * Purpose:	v2 B-tree callback for dense attribute storage record removal
@@ -985,41 +1055,21 @@ H5A_dense_remove_bt2_cb(const void *_record, void *_bt2_udata)
 
     /* Check for inserting shared attribute */
     if(record->flags & H5O_MSG_FLAG_SHARED) {
-        H5A_fh_ud_cp_t fh_udata;            /* User data for fractal heap 'op' callback */
         H5O_shared_t sh_mesg;               /* Shared object header message */
 
-        /* Set up the user data for fractal heap 'op' callback */
-        fh_udata.f = bt2_udata->f;
-        fh_udata.dxpl_id = bt2_udata->dxpl_id;
-        fh_udata.attr = NULL;
-
-        /* Call fractal heap 'op' routine, to get copy of the attribute */
-        if(H5HF_op(bt2_udata->shared_fheap, bt2_udata->dxpl_id, record->id,
-                H5A_dense_copy_fh_cb, &fh_udata) < 0)
-            HGOTO_ERROR(H5E_ATTR, H5E_CANTOPERATE, FAIL, "attribute removal callback failed")
-
         /* Get the shared information for the attribute */
-        if(NULL == H5O_attr_get_share(fh_udata.attr, &sh_mesg))
+        if(NULL == H5O_attr_get_share(*(H5A_t **)bt2_udata->found_op_data, &sh_mesg))
             HGOTO_ERROR(H5E_ATTR, H5E_BADMESG, FAIL, "can't get shared message")
 
         /* Decrement the reference count on the shared attribute message */
         if(H5SM_try_delete(bt2_udata->f, bt2_udata->dxpl_id, H5O_ATTR_ID, &sh_mesg) < 0)
             HGOTO_ERROR(H5E_ATTR, H5E_CANTFREE, FAIL, "unable to delete shared attribute")
-
-        /* Release the space allocated for the attribute */
-        H5O_msg_free(H5O_ATTR_ID, fh_udata.attr);
     } /* end if */
     else {
-        H5A_fh_ud_rm_t fh_udata;            /* User data for fractal heap 'op' callback */
-
-        /* Set up the user data for fractal heap 'op' callback */
-        fh_udata.f = bt2_udata->f;
-        fh_udata.dxpl_id = bt2_udata->dxpl_id;
-
-        /* Call fractal heap 'op' routine, to perform user callback */
-        if(H5HF_op(bt2_udata->fheap, bt2_udata->dxpl_id, record->id,
-                H5A_dense_remove_fh_cb, &fh_udata) < 0)
-            HGOTO_ERROR(H5E_ATTR, H5E_CANTOPERATE, FAIL, "attribute removal callback failed")
+        /* Perform the deletion action on the attribute */
+        /* (takes care of shared & committed datatype/dataspace components) */
+        if(H5O_attr_delete(bt2_udata->f, bt2_udata->dxpl_id, *(H5A_t **)bt2_udata->found_op_data, TRUE) < 0)
+            HGOTO_ERROR(H5E_ATTR, H5E_CANTDELETE, FAIL, "unable to delete attribute")
 
         /* Remove record from fractal heap */
         if(H5HF_remove(bt2_udata->fheap, bt2_udata->dxpl_id, record->id) < 0)
@@ -1050,6 +1100,7 @@ H5A_dense_remove(H5F_t *f, hid_t dxpl_id, const H5O_t *oh, const char *name)
     H5A_bt2_ud_common_t udata;          /* User data for v2 B-tree record removal */
     H5HF_t *fheap = NULL;               /* Fractal heap handle */
     H5HF_t *shared_fheap = NULL;        /* Fractal heap handle for shared header messages */
+    H5A_t *attr_copy = NULL;            /* Copy of attribute to remove */
     htri_t attr_sharable;               /* Flag indicating attributes are sharable */
     herr_t ret_value = SUCCEED;         /* Return value */
 
@@ -1092,8 +1143,8 @@ H5A_dense_remove(H5F_t *f, hid_t dxpl_id, const H5O_t *oh, const char *name)
     udata.name_hash = H5_checksum_lookup3(name, HDstrlen(name), 0);
     udata.flags = 0;
     udata.corder = -1;   /* XXX: None yet */
-    udata.found_op = NULL;
-    udata.found_op_data = NULL;
+    udata.found_op = H5A_dense_fnd_cb;       /* v2 B-tree comparison callback */
+    udata.found_op_data = &attr_copy;
 
     /* Remove the record from the name index v2 B-tree */
     if(H5B2_remove(f, dxpl_id, H5A_BT2_NAME, oh->name_bt2_addr, &udata, H5A_dense_remove_bt2_cb, &udata) < 0)
@@ -1105,6 +1156,9 @@ done:
         HDONE_ERROR(H5E_ATTR, H5E_CLOSEERROR, FAIL, "can't close fractal heap")
     if(fheap && H5HF_close(fheap, dxpl_id) < 0)
         HDONE_ERROR(H5E_ATTR, H5E_CLOSEERROR, FAIL, "can't close fractal heap")
+    if(attr_copy)
+        H5O_msg_free_real(H5O_MSG_ATTR, attr_copy);
+
 
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5A_dense_remove() */
diff --git a/src/H5Aint.c b/src/H5Aint.c
index 1d6e9ab..456717b 100644
--- a/src/H5Aint.c
+++ b/src/H5Aint.c
@@ -126,7 +126,7 @@ H5A_compact_build_table_cb(H5O_t UNUSED *oh, H5O_mesg_t *mesg/*in,out*/,
     /* Check for re-allocating table */
     if(udata->curr_attr == udata->atable->nattrs) {
         size_t n = MAX(1, 2 * udata->atable->nattrs);
-        H5A_t *table = H5MM_realloc(udata->atable->attrs,
+        H5A_t *table = (H5A_t *)H5MM_realloc(udata->atable->attrs,
                                           n * sizeof(H5A_t));
 
         if(!table)
@@ -142,11 +142,11 @@ H5A_compact_build_table_cb(H5O_t UNUSED *oh, H5O_mesg_t *mesg/*in,out*/,
 	 * H5O_MSG_SHARED message.  We use that information to look up the real
 	 * message in the global heap or some other object header.
 	 */
-        if(NULL == H5O_shared_read(udata->f, udata->dxpl_id, mesg->native, H5O_MSG_ATTR, &udata->atable->attrs[udata->curr_attr]))
+        if(NULL == H5O_shared_read(udata->f, udata->dxpl_id, (const H5O_shared_t *)mesg->native, H5O_MSG_ATTR, &udata->atable->attrs[udata->curr_attr]))
 	    HGOTO_ERROR(H5E_ATTR, H5E_CANTCOPY, H5_ITER_ERROR, "unable to read shared attribute")
     } /* end if */
     else {
-        if(NULL == H5A_copy(&udata->atable->attrs[udata->curr_attr], mesg->native))
+        if(NULL == H5A_copy(&udata->atable->attrs[udata->curr_attr], (const H5A_t *)mesg->native))
             HGOTO_ERROR(H5E_ATTR, H5E_CANTCOPY, H5_ITER_ERROR, "can't copy attribute")
     } /* end else */
 
@@ -300,7 +300,7 @@ H5A_dense_build_table(H5F_t *f, hid_t dxpl_id, hsize_t nattrs, haddr_t attr_fhea
         H5A_attr_iter_op_t attr_op;    /* Attribute operator */
 
         /* Allocate the table to store the attributes */
-        if((atable->attrs = H5MM_malloc(sizeof(H5A_t) * atable->nattrs)) == NULL)
+        if((atable->attrs = (H5A_t *)H5MM_malloc(sizeof(H5A_t) * atable->nattrs)) == NULL)
             HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed")
 
         /* Set up user data for iteration */
diff --git a/src/H5Apkg.h b/src/H5Apkg.h
index 8aa73fb..238546f 100644
--- a/src/H5Apkg.h
+++ b/src/H5Apkg.h
@@ -166,6 +166,8 @@ H5_DLL H5A_t *H5A_dense_open(H5F_t *f, hid_t dxpl_id, const H5O_t *oh,
     const char *name);
 H5_DLL herr_t H5A_dense_write(H5F_t *f, hid_t dxpl_id, const H5O_t *oh,
     H5A_t *attr);
+H5_DLL herr_t H5A_dense_rename(H5F_t *f, hid_t dxpl_id, const H5O_t *oh,
+    const char *old_name, const char *new_name);
 H5_DLL herr_t H5A_dense_iterate(H5F_t *f, hid_t dxpl_id, hid_t loc_id,
     haddr_t attr_fheap_addr, haddr_t name_bt2_addr, H5_iter_order_t order,
     unsigned skip, unsigned *last_attr, const H5A_attr_iter_op_t *attr_op,
diff --git a/src/H5Oattr.c b/src/H5Oattr.c
index acfc720..8d2aa18 100644
--- a/src/H5Oattr.c
+++ b/src/H5Oattr.c
@@ -181,18 +181,18 @@ H5O_attr_decode(H5F_t *f, hid_t dxpl_id, const uint8_t *p)
 	H5O_shared_t *shared;   /* Shared information */
 
         /* Get the shared information */
-	if (NULL == (shared = (H5O_MSG_SHARED->decode)(f, dxpl_id, p)))
+	if (NULL == (shared = (H5O_shared_t *)(H5O_MSG_SHARED->decode)(f, dxpl_id, p)))
 	    HGOTO_ERROR(H5E_OHDR, H5E_CANTDECODE, NULL, "unable to decode shared message")
 
         /* Get the actual datatype information */
-        if((attr->dt = H5O_shared_read(f, dxpl_id, shared, H5O_MSG_DTYPE, NULL)) == NULL)
+        if((attr->dt = (H5T_t *)H5O_shared_read(f, dxpl_id, shared, H5O_MSG_DTYPE, NULL)) == NULL)
             HGOTO_ERROR(H5E_ATTR, H5E_CANTDECODE, NULL, "can't decode attribute datatype")
 
         /* Free the shared information */
         H5O_msg_free_real(H5O_MSG_SHARED, shared);
     } /* end if */
     else {
-        if((attr->dt = (H5O_MSG_DTYPE->decode)(f, dxpl_id, p)) == NULL)
+        if((attr->dt = (H5T_t *)(H5O_MSG_DTYPE->decode)(f, dxpl_id, p)) == NULL)
             HGOTO_ERROR(H5E_ATTR, H5E_CANTDECODE, NULL, "can't decode attribute datatype")
     } /* end else */
     if(version < H5O_ATTR_VERSION_2)
@@ -210,18 +210,18 @@ H5O_attr_decode(H5F_t *f, hid_t dxpl_id, const uint8_t *p)
 	H5O_shared_t *shared;   /* Shared information */
 
         /* Get the shared information */
-	if (NULL == (shared = (H5O_MSG_SHARED->decode) (f, dxpl_id, p)))
+	if (NULL == (shared = (H5O_shared_t *)(H5O_MSG_SHARED->decode)(f, dxpl_id, p)))
 	    HGOTO_ERROR(H5E_OHDR, H5E_CANTDECODE, NULL, "unable to decode shared message")
 
         /* Get the actual datatype information */
-        if((extent= H5O_shared_read(f, dxpl_id, shared, H5O_MSG_SDSPACE, NULL))==NULL)
+        if((extent= (H5S_extent_t *)H5O_shared_read(f, dxpl_id, shared, H5O_MSG_SDSPACE, NULL))==NULL)
             HGOTO_ERROR(H5E_ATTR, H5E_CANTDECODE, NULL, "can't decode attribute dataspace")
 
         /* Free the shared information */
         H5O_msg_free_real(H5O_MSG_SHARED, shared);
     } /* end if */
     else {
-        if((extent = (H5O_MSG_SDSPACE->decode)(f, dxpl_id, p)) == NULL)
+        if((extent = (H5S_extent_t *)(H5O_MSG_SDSPACE->decode)(f, dxpl_id, p)) == NULL)
             HGOTO_ERROR(H5E_ATTR, H5E_CANTDECODE, NULL, "can't decode attribute dataspace")
     } /* end else */
 
@@ -473,7 +473,7 @@ H5O_attr_copy(const void *_src, void *_dst)
     HDassert(_src);
 
     /* copy */
-    if(NULL == (ret_value = H5A_copy(_dst, _src)))
+    if(NULL == (ret_value = (H5A_t *)H5A_copy((H5A_t *)_dst, (const H5A_t *)_src)))
         HGOTO_ERROR(H5E_ATTR, H5E_CANTINIT, NULL, "can't copy attribute")
 
 done:
@@ -1065,9 +1065,9 @@ done:
         if(H5I_dec_ref(tid_mem) < 0)
             HDONE_ERROR(H5E_DATASET, H5E_CANTFREE, NULL, "Can't decrement temporary datatype ID")
     if(buf)
-        H5FL_BLK_FREE(attr_buf, buf);
+        buf = H5FL_BLK_FREE(attr_buf, buf);
     if(reclaim_buf)
-        H5FL_BLK_FREE(attr_buf, reclaim_buf);
+        reclaim_buf = H5FL_BLK_FREE(attr_buf, reclaim_buf);
 
     /* Release destination attribute information on failure */
     if(!ret_value)
diff --git a/src/H5Oattribute.c b/src/H5Oattribute.c
index 576ce29..b3b19d4 100644
--- a/src/H5Oattribute.c
+++ b/src/H5Oattribute.c
@@ -527,7 +527,7 @@ done:
  *
  * Programmer:	Quincey Koziol
  *		koziol@hdfgroup.org
- *		Jan  2 2006
+ *		Jan  2 2007
  *
  *-------------------------------------------------------------------------
  */
@@ -547,7 +547,7 @@ H5O_attr_update_shared(H5F_t *f, hid_t dxpl_id, H5A_t *attr,
 
     /* Increment reference count on attribute components */
     /* (Otherwise they may be deleted when the old attribute
-     * message is deleted.)
+     * message is removed from the shared message storage.)
      */
     if(H5O_attr_link(f, dxpl_id, attr) < 0)
         HGOTO_ERROR(H5E_ATTR, H5E_LINKCOUNT, FAIL, "unable to adjust attribute link count")
@@ -559,7 +559,7 @@ H5O_attr_update_shared(H5F_t *f, hid_t dxpl_id, H5A_t *attr,
     else if(shared_mesg < 0)
         HGOTO_ERROR(H5E_ATTR, H5E_BADMESG, FAIL, "can't share attribute")
 
-    /* Remove the old attribute from the SOHM index */
+    /* Remove the old attribute from the SOHM storage */
     if(H5SM_try_delete(f, dxpl_id, H5O_ATTR_ID, sh_mesg) < 0)
         HGOTO_ERROR(H5E_ATTR, H5E_CANTFREE, FAIL, "unable to delete shared attribute in shared storage")
 
@@ -610,11 +610,11 @@ H5O_attr_write_cb(H5O_t UNUSED *oh, H5O_mesg_t *mesg/*in,out*/,
 
         /* Check for correct attribute message to modify */
         if(HDstrcmp(shared_attr.name, udata->attr->name) == 0) {
-            /* Update the shared attribute in the SOHM info */
+            /* Update the shared attribute in the SOHM storage */
             if(H5O_attr_update_shared(udata->f, udata->dxpl_id, udata->attr, (const H5O_shared_t *)mesg->native) < 0)
                 HGOTO_ERROR(H5E_ATTR, H5E_CANTUPDATE, H5_ITER_ERROR, "unable to update attribute in shared storage")
 
-            /* Extract shared message info from current attribute */
+            /* Extract updated shared message info from modified attribute */
             if(NULL == H5O_attr_get_share(udata->attr, (H5O_shared_t *)mesg->native))
                 HGOTO_ERROR(H5E_ATTR, H5E_BADMESG, H5_ITER_ERROR, "can't get shared info")
 
@@ -799,6 +799,11 @@ done:
  * Purpose:	Object header iterator callback routine to change name of
  *              attribute during rename
  *
+ * Note:	This routine doesn't currently allow an attribute to change
+ *              its "shared" status, if the name change would cause a size
+ *              difference that would put it into a different category.
+ *              Something for later...
+ *
  * Return:	Non-negative on success/Negative on failure
  *
  * Programmer:	Quincey Koziol
@@ -835,9 +840,23 @@ H5O_attr_rename_mod_cb(H5O_t *oh, H5O_mesg_t *mesg/*in,out*/,
 
         /* Check for correct attribute message to modify */
         if(HDstrcmp(shared_attr.name, udata->old_name) == 0) {
-/* XXX: fix me */
-HDfprintf(stderr, "%s: renaming a shared attribute not supported yet!\n", FUNC);
-HGOTO_ERROR(H5E_ATTR, H5E_UNSUPPORTED, H5_ITER_ERROR, "renaming a shared attribute not supported yet")
+            /* Change the name for the attribute */
+            H5MM_xfree(shared_attr.name);
+            shared_attr.name = H5MM_xstrdup(udata->new_name);
+
+            /* Mark message as dirty */
+            mesg->dirty = TRUE;
+
+            /* Update the shared attribute in the SOHM storage */
+            if(H5O_attr_update_shared(udata->f, udata->dxpl_id, &shared_attr, (const H5O_shared_t *)mesg->native) < 0)
+                HGOTO_ERROR(H5E_ATTR, H5E_CANTUPDATE, H5_ITER_ERROR, "unable to update attribute in shared storage")
+
+            /* Extract updated shared message info from modified attribute */
+            if(NULL == H5O_attr_get_share(&shared_attr, (H5O_shared_t *)mesg->native))
+                HGOTO_ERROR(H5E_ATTR, H5E_BADMESG, H5_ITER_ERROR, "can't get shared info")
+
+            /* Indicate that we found the correct attribute */
+            udata->found = TRUE;
         } /* end if */
 
         /* Release copy of shared attribute */
@@ -867,7 +886,7 @@ HGOTO_ERROR(H5E_ATTR, H5E_UNSUPPORTED, H5_ITER_ERROR, "renaming a shared attribu
                  *      list of messages during the "add the modified attribute"
                  *      step, invalidating the message pointer we have here - QAK)
                  */
-                attr = mesg->native;
+                attr = (H5A_t *)mesg->native;
                 mesg->native = NULL;
 
                 /* If the later version of the object header format, decrement attribute */
@@ -897,6 +916,7 @@ HGOTO_ERROR(H5E_ATTR, H5E_UNSUPPORTED, H5_ITER_ERROR, "renaming a shared attribu
                     HGOTO_ERROR(H5E_ATTR, H5E_CANTINSERT, H5_ITER_ERROR, "unable to relocate renamed attribute in header")
 
                 /* Decrement the link count on shared components */
+                /* (to balance all the link count adjustments out) */
                 if(H5O_attr_delete(udata->f, udata->dxpl_id, attr, TRUE) < 0)
                     HGOTO_ERROR(H5E_ATTR, H5E_CANTDELETE, H5_ITER_ERROR, "unable to delete attribute")
 
@@ -906,15 +926,18 @@ HGOTO_ERROR(H5E_ATTR, H5E_UNSUPPORTED, H5_ITER_ERROR, "renaming a shared attribu
 
             /* Indicate that we found an existing attribute with the old name */
             udata->found = TRUE;
-
-            /* Stop iterating */
-            ret_value = H5_ITER_STOP;
-
-            /* Indicate that the object header was modified */
-            *oh_flags_ptr |= H5AC__DIRTIED_FLAG;
         } /* end if */
     } /* end else */
 
+    /* Set common info, if we found the correct attribute */
+    if(udata->found) {
+        /* Stop iterating */
+        ret_value = H5_ITER_STOP;
+
+        /* Indicate that the object header was modified */
+        *oh_flags_ptr |= H5AC__DIRTIED_FLAG;
+    } /* end if */
+
 done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5O_attr_rename_mod_cb() */
@@ -933,7 +956,8 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5O_attr_rename(const H5O_loc_t *loc, hid_t dxpl_id, const char *old_name, const char *new_name)
+H5O_attr_rename(const H5O_loc_t *loc, hid_t dxpl_id, const char *old_name,
+    const char *new_name)
 {
     H5O_t *oh = NULL;                   /* Pointer to actual object header */
     unsigned oh_flags = H5AC__NO_FLAGS_SET;     /* Metadata cache flags for object header */
@@ -952,9 +976,9 @@ H5O_attr_rename(const H5O_loc_t *loc, hid_t dxpl_id, const char *old_name, const
 
     /* Check for attributes stored densely */
     if(H5F_addr_defined(oh->attr_fheap_addr)) {
-/* XXX: fix me */
-HDfprintf(stderr, "%s: renaming attributes in dense storage not supported yet!\n", FUNC);
-HGOTO_ERROR(H5E_ATTR, H5E_UNSUPPORTED, FAIL, "renaming attributes in dense storage not supported yet")
+        /* Rename the attribute data in dense storage */
+        if(H5A_dense_rename(loc->file, dxpl_id, oh, old_name, new_name) < 0)
+            HGOTO_ERROR(H5E_ATTR, H5E_CANTUPDATE, FAIL, "error updating attribute")
     } /* end if */
     else {
         H5O_iter_ren_t udata;           /* User data for callback */
@@ -1118,6 +1142,7 @@ H5O_attr_remove_cb(H5O_t *oh, H5O_mesg_t *mesg/*in,out*/,
         if(NULL == H5O_shared_read(udata->f, udata->dxpl_id, (const H5O_shared_t *)mesg->native, H5O_MSG_ATTR, &shared_attr))
 	    HGOTO_ERROR(H5E_ATTR, H5E_CANTINIT, H5_ITER_ERROR, "unable to read shared attribute")
 
+/* XXX: fix me */
 HDfprintf(stderr, "%s: removing a shared attribute not supported yet!\n", FUNC);
 HGOTO_ERROR(H5E_ATTR, H5E_UNSUPPORTED, FAIL, "deleting a shared attribute not supported yet")
 #ifdef NOT_YET