[svn-r13121] Description:

    Add support & tests for using shared datatypes with shared & un-shared
attributes.  Involves some fairly icky code to make the "copy on write"
paradigm for shared attributes work.

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

12 files changed, 247 insertions, 184 deletions

diff --git a/src/H5Adense.c b/src/H5Adense.c
index d64bb89..e4cf59e 100644
--- a/src/H5Adense.c
+++ b/src/H5Adense.c
@@ -801,9 +801,29 @@ H5A_dense_rename(H5F_t *f, hid_t dxpl_id, const H5O_t *oh, const char *old_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)
+    if((shared_mesg = H5SM_try_share(f, dxpl_id, H5O_ATTR_ID, attr_copy)) > 0) {
+        hsize_t attr_rc;                /* Attribute's ref count in shared message storage */
+
         /* Mark the message as shared */
         mesg_flags |= H5O_MSG_FLAG_SHARED;
+
+        /* Retrieve ref count for shared attribute */
+        if(H5SM_get_refcount(f, dxpl_id, H5O_ATTR_ID, &attr_copy->sh_loc, &attr_rc) < 0)
+            HGOTO_ERROR(H5E_ATTR, H5E_CANTGET, FAIL, "can't retrieve shared message ref count")
+
+        /* If the newly shared attribute needs to share "ownership" of the shared
+         *      components (ie. its reference count is 1), increment the reference
+         *      count on any shared components of the attribute, so that they won't
+         *      be removed from the file.  (Essentially a "copy on write" operation).
+         *
+         *      *ick* -QAK, 2007/01/08
+         */
+        if(attr_rc == 1) {
+            /* Increment reference count on attribute components */
+            if(H5O_attr_link(f, dxpl_id, attr_copy) < 0)
+                HGOTO_ERROR(H5E_ATTR, H5E_LINKCOUNT, FAIL, "unable to adjust attribute link count")
+        } /* end if */
+    } /* end if */
     else if(shared_mesg < 0)
 	HGOTO_ERROR(H5E_ATTR, H5E_WRITEERROR, FAIL, "error determining if message should be shared")
 
diff --git a/src/H5Atest.c b/src/H5Atest.c
index b2ee0d5..13d13f1 100644
--- a/src/H5Atest.c
+++ b/src/H5Atest.c
@@ -29,8 +29,6 @@
 
 #define H5A_PACKAGE		/*suppress error about including H5Apkg  */
 #define H5A_TESTING		/*suppress warning about H5A testing funcs*/
-#define H5SM_PACKAGE		/*suppress error about including H5SMpkg  */
-#define H5SM_TESTING		/*suppress warning about H5SM testing funcs*/
 
 
 /***********/
@@ -40,7 +38,7 @@
 #include "H5Apkg.h"		/* Attributes	  			*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5Iprivate.h"		/* IDs			  		*/
-#include "H5SMpkg.h"            /* Shared object header messages        */
+#include "H5SMprivate.h"        /* Shared object header messages        */
 
 
 /****************/
@@ -140,7 +138,7 @@ H5A_get_shared_rc_test(hid_t attr_id, hsize_t *ref_count)
     HDassert(H5O_attr_is_shared(attr));
 
     /* Retrieve ref count for shared attribute */
-    if(H5SM_get_refcount_test(attr->oloc.file, H5AC_ind_dxpl_id, H5O_ATTR_ID,
+    if(H5SM_get_refcount(attr->oloc.file, H5AC_ind_dxpl_id, H5O_ATTR_ID,
             &attr->sh_loc, ref_count) < 0)
         HGOTO_ERROR(H5E_ATTR, H5E_CANTGET, FAIL, "can't retrieve shared message ref count")
 
diff --git a/src/H5O.c b/src/H5O.c
index e235405..103352e 100644
--- a/src/H5O.c
+++ b/src/H5O.c
@@ -933,11 +933,8 @@ int
 H5O_link(const H5O_loc_t *loc, int adjust, hid_t dxpl_id)
 {
     H5O_t	*oh = NULL;
-    unsigned oh_flags = H5AC__NO_FLAGS_SET; /* used to indicate whether the
-                                            * object was deleted as a result
-                                            * of this action.
-                                            */
-    int	ret_value = FAIL;
+    unsigned oh_flags = H5AC__NO_FLAGS_SET; /* Whether the object was deleted  */
+    int	ret_value;                          /* Return value */
 
     FUNC_ENTER_NOAPI(H5O_link, FAIL)
 
diff --git a/src/H5Oattr.c b/src/H5Oattr.c
index 8d2aa18..d8f4a1b 100644
--- a/src/H5Oattr.c
+++ b/src/H5Oattr.c
@@ -662,23 +662,23 @@ H5O_attr_delete(H5F_t *f, hid_t dxpl_id, const void *_mesg, hbool_t adj_link)
      * shared there.
      */
     if((tri_ret = H5O_msg_is_shared(H5O_DTYPE_ID, attr->dt)) < 0)
-        HGOTO_ERROR(H5E_OHDR, H5E_BADMESG, FAIL, "can't tell if datatype is shared")
+        HGOTO_ERROR(H5E_ATTR, H5E_BADMESG, FAIL, "can't tell if datatype is shared")
     if(tri_ret > 0)
     {
         if(NULL == H5O_msg_get_share(H5O_DTYPE_ID, attr->dt, &sh_mesg))
-            HGOTO_ERROR(H5E_OHDR, H5E_BADMESG, FAIL, "can't get shared message from datatype")
-        if(H5SM_try_delete(f, H5AC_dxpl_id, H5O_DTYPE_ID, &sh_mesg) < 0)
-            HGOTO_ERROR(H5E_SOHM, H5E_CANTREMOVE, FAIL, "can't remove datatype from SOHM heap")
+            HGOTO_ERROR(H5E_ATTR, H5E_BADMESG, FAIL, "can't get shared message from datatype")
+        if(H5SM_try_delete(f, dxpl_id, H5O_DTYPE_ID, &sh_mesg) < 0)
+            HGOTO_ERROR(H5E_ATTR, H5E_CANTREMOVE, FAIL, "can't remove datatype from SOHM heap")
     } /* end if */
 
     if((tri_ret = H5O_msg_is_shared(H5O_SDSPACE_ID, attr->ds)) < 0)
-        HGOTO_ERROR(H5E_OHDR, H5E_BADMESG, FAIL, "can't tell if dataspace is shared")
+        HGOTO_ERROR(H5E_ATTR, H5E_BADMESG, FAIL, "can't tell if dataspace is shared")
     if(tri_ret > 0)
     {
         if(NULL == H5O_msg_get_share(H5O_SDSPACE_ID, attr->ds, &sh_mesg))
-            HGOTO_ERROR(H5E_OHDR, H5E_BADMESG, FAIL, "can't get shared message from dataspace")
-        if(H5SM_try_delete(f, H5AC_dxpl_id, H5O_SDSPACE_ID, &sh_mesg) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_SOHM, FAIL, "can't remove dataspace from SOHM heap")
+            HGOTO_ERROR(H5E_ATTR, H5E_BADMESG, FAIL, "can't get shared message from dataspace")
+        if(H5SM_try_delete(f, dxpl_id, H5O_SDSPACE_ID, &sh_mesg) < 0)
+            HGOTO_ERROR(H5E_ATTR, H5E_SOHM, FAIL, "can't remove dataspace from SOHM heap")
     } /* end if */
 
     /* Check whether datatype is shared */
@@ -686,7 +686,7 @@ H5O_attr_delete(H5F_t *f, hid_t dxpl_id, const void *_mesg, hbool_t adj_link)
         /* Decrement the reference count on the shared datatype, if requested */
         if(adj_link)
             if(H5T_link(attr->dt, -1, dxpl_id) < 0)
-                HGOTO_ERROR(H5E_OHDR, H5E_LINKCOUNT, FAIL, "unable to adjust shared datatype link count")
+                HGOTO_ERROR(H5E_ATTR, H5E_LINKCOUNT, FAIL, "unable to adjust shared datatype link count")
     } /* end if */
 
 done:
@@ -733,7 +733,7 @@ H5O_attr_link(H5F_t *f, hid_t dxpl_id, const void *_mesg)
     if(H5T_committed(attr->dt)) {
         /* Increment the reference count on the shared datatype */
         if(H5T_link(attr->dt, 1, dxpl_id) < 0)
-            HGOTO_ERROR(H5E_OHDR, H5E_LINKCOUNT, FAIL, "unable to adjust shared datatype link count")
+            HGOTO_ERROR(H5E_ATTR, H5E_LINKCOUNT, FAIL, "unable to adjust shared datatype link count")
     } /* end if */
 
 done:
@@ -1155,7 +1155,6 @@ htri_t
 H5O_attr_is_shared(const void *_mesg)
 {
     const H5A_t  *mesg = (const H5A_t *)_mesg;
-    htri_t       ret_value;
 
     FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5O_attr_is_shared)
 
@@ -1165,12 +1164,7 @@ H5O_attr_is_shared(const void *_mesg)
      * library read a "committed attribute" if we ever create one in
      * the future.
      */
-    if(H5O_IS_SHARED(mesg->sh_loc.flags))
-        ret_value = TRUE;
-    else
-        ret_value = FALSE;
-
-    FUNC_LEAVE_NOAPI(ret_value)
+    FUNC_LEAVE_NOAPI(H5O_IS_SHARED(mesg->sh_loc.flags))
 } /* end H5O_attr_is_shared */
 
 
diff --git a/src/H5Oattribute.c b/src/H5Oattribute.c
index b1e8d31..ea77e26 100644
--- a/src/H5Oattribute.c
+++ b/src/H5Oattribute.c
@@ -235,9 +235,54 @@ HDfprintf(stderr, "%s: adding attribute, attr->name = '%s'\n", FUNC, attr->name)
     HDassert(attr);
 
     /* Should this message be written as a SOHM? */
-    if((shared_mesg = H5SM_try_share(loc->file, dxpl_id, H5O_ATTR_ID, attr)) > 0)
+    if((shared_mesg = H5SM_try_share(loc->file, dxpl_id, H5O_ATTR_ID, attr)) > 0) {
+        hsize_t attr_rc;                /* Attribute's ref count in shared message storage */
+
         /* Mark the message as shared */
         mesg_flags |= H5O_MSG_FLAG_SHARED;
+
+        /* Check whether datatype is committed */
+        /* (to maintain ref. count incr/decr similarity with "shared message"
+         *      type of datatype sharing)
+         */
+        if(H5T_committed(attr->dt)) {
+            /* Increment the reference count on the shared datatype */
+            if(H5T_link(attr->dt, 1, dxpl_id) < 0)
+                HGOTO_ERROR(H5E_OHDR, H5E_LINKCOUNT, FAIL, "unable to adjust shared datatype link count")
+        } /* end if */
+
+        /* Retrieve ref count for shared attribute */
+        if(H5SM_get_refcount(loc->file, dxpl_id, H5O_ATTR_ID, &attr->sh_loc, &attr_rc) < 0)
+            HGOTO_ERROR(H5E_ATTR, H5E_CANTGET, FAIL, "can't retrieve shared message ref count")
+
+        /* If this is not the first copy of the attribute in the shared message
+         *      storage, decrement the reference count on any shared components
+         *      of the attribute.  This is done because the shared message
+         *      storage's "try delete" call doesn't call the message class's
+         *      "delete" callback until the reference count drops to zero.
+         *      However, attributes have already increased the reference
+         *      count on shared components before passing the attribute
+         *      to the shared message code to manage, causing an assymetry
+         *      in the reference counting for any shared components.
+         *
+         *      The alternate solution is to have the shared message's "try
+         *      delete" code always call the message class's "delete" callback,
+         *      even when the reference count is positive.  This can be done
+         *      without an appreciable performance hit (by using H5HF_op() in
+         *      the shared message comparison v2 B-tree callback), but it has
+         *      the undesirable side-effect of leaving the reference count on
+         *      the attribute's shared components artificially (and possibly
+         *      misleadingly) high, because there's only one shared attribute
+         *      referencing the shared components, not <refcount for the
+         *      shared attribute> objects referencing the shared components.
+         *
+         *      *ick* -QAK, 2007/01/08
+         */
+        if(attr_rc > 1) {
+            if(H5O_attr_delete(loc->file, dxpl_id, attr, TRUE) < 0)
+                HGOTO_ERROR(H5E_ATTR, H5E_CANTDELETE, FAIL, "unable to delete attribute")
+        } /* end if */
+    } /* end if */
     else if(shared_mesg < 0)
 	HGOTO_ERROR(H5E_ATTR, H5E_WRITEERROR, FAIL, "error determining if message should be shared")
 
@@ -535,6 +580,7 @@ herr_t
 H5O_attr_update_shared(H5F_t *f, hid_t dxpl_id, H5A_t *attr, 
     const H5O_shared_t *sh_mesg)
 {
+    hsize_t attr_rc;                    /* Attribute's ref count in shared message storage */
     htri_t shared_mesg;                 /* Whether the message should be shared */
     herr_t ret_value = SUCCEED;         /* Return value */
 
@@ -545,13 +591,6 @@ H5O_attr_update_shared(H5F_t *f, hid_t dxpl_id, H5A_t *attr,
     HDassert(attr);
     HDassert(sh_mesg);
 
-    /* Increment reference count on attribute components */
-    /* (Otherwise they may be deleted when the old attribute
-     * 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")
-
     /* Store new version of message as a SOHM */
     /* (should always work, since we're not changing the size of the attribute) */
     if((shared_mesg = H5SM_try_share(f, dxpl_id, H5O_ATTR_ID, attr)) == 0)
@@ -559,6 +598,23 @@ 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")
 
+    /* Retrieve shared message storage ref count for new shared attribute */
+    if(H5SM_get_refcount(f, dxpl_id, H5O_ATTR_ID, &attr->sh_loc, &attr_rc) < 0)
+        HGOTO_ERROR(H5E_ATTR, H5E_CANTGET, FAIL, "can't retrieve shared message ref count")
+
+    /* If the newly shared attribute needs to share "ownership" of the shared
+     *      components (ie. its reference count is 1), increment the reference
+     *      count on any shared components of the attribute, so that they won't
+     *      be removed from the file.  (Essentially a "copy on write" operation).
+     *
+     *      *ick* -QAK, 2007/01/08
+     */
+    if(attr_rc == 1) {
+        /* Increment reference count on attribute components */
+        if(H5O_attr_link(f, dxpl_id, attr) < 0)
+            HGOTO_ERROR(H5E_ATTR, H5E_LINKCOUNT, FAIL, "unable to adjust attribute link count")
+    } /* end if */
+
     /* 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")
diff --git a/src/H5Oshared.c b/src/H5Oshared.c
index 6c5189d..68d3494 100644
--- a/src/H5Oshared.c
+++ b/src/H5Oshared.c
@@ -37,7 +37,7 @@
 #include "H5HFprivate.h"        /* Fractal heap				*/
 #include "H5MMprivate.h"	/* Memory management			*/
 #include "H5Opkg.h"             /* Object headers			*/
-#include "H5SMprivate.h"        /* Shared messages			*/
+#include "H5SMprivate.h"        /* Shared object header messages        */
 
 static void *H5O_shared_decode(H5F_t*, hid_t dxpl_id, const uint8_t*);
 static herr_t H5O_shared_encode(H5F_t*, uint8_t*, const void*);
diff --git a/src/H5SM.c b/src/H5SM.c
index 6e5dba8..49052eb 100755
--- a/src/H5SM.c
+++ b/src/H5SM.c
@@ -1441,3 +1441,136 @@ H5SM_reconstitute(H5O_shared_t *sh_mesg, const uint8_t *heap_id)
     FUNC_LEAVE_NOAPI(SUCCEED)
 } /* end H5SM_reconstitute() */
 
+
+/*-------------------------------------------------------------------------
+ * Function:	H5SM_get_refcount_bt2_cb
+ *
+ * Purpose:	v2 B-tree 'find' callback to retrieve the record for a message
+ *
+ * Return:	SUCCEED/FAIL
+ *
+ * Programmer:	Quincey Koziol
+ *              Tuesday, December 19, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5SM_get_refcount_bt2_cb(const void *_record, void *_op_data)
+{
+    const H5SM_sohm_t *record = (const H5SM_sohm_t *)_record;  /* v2 B-tree record for message */
+    H5SM_sohm_t *op_data = (H5SM_sohm_t *)_op_data;       /* "op data" from v2 B-tree find */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5SM_get_refcount_bt2_cb)
+
+    /*
+     * Check arguments.
+     */
+    HDassert(record);
+    HDassert(op_data);
+
+    /* Make a copy of the record */
+    *op_data = *record;
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5SM_get_refcount_bt2_cb() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5SM_get_refcount
+ *
+ * Purpose:     Retrieve the reference count for a message
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Quincey Koziol
+ *              Tuesday, December 19, 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5SM_get_refcount(H5F_t *f, hid_t dxpl_id, unsigned type_id,
+    const H5O_shared_t *sh_mesg, hsize_t *ref_count)
+{    
+    H5HF_t *fheap = NULL;               /* Fractal heap that contains shared messages */
+    H5SM_master_table_t *table = NULL;  /* SOHM master table */
+    H5SM_list_t *list = NULL;           /* SOHM index list for message type (if in list form) */
+    H5SM_index_header_t *header=NULL;   /* Index header for message type */
+    H5SM_mesg_key_t key;                /* Key for looking up message */
+    H5SM_fh_ud_gh_t udata;              /* User data for fractal heap 'op' callback */
+    H5SM_sohm_t message;                /* Record for shared message */
+    ssize_t index_num;                  /* Table index for message type */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5SM_get_refcount)
+
+    /* Sanity check */
+    HDassert(f);
+    HDassert(sh_mesg);
+    HDassert(ref_count);
+
+    /* Look up the master SOHM table */
+    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, f->shared->sohm_addr, NULL, NULL, H5AC_READ)))
+	HGOTO_ERROR(H5E_CACHE, H5E_CANTPROTECT, FAIL, "unable to load SOHM master table")
+
+    /* Find the correct index and try to delete from it */
+    if((index_num = H5SM_get_index(table, type_id)) < 0)
+	HGOTO_ERROR(H5E_SOHM, H5E_NOTFOUND, FAIL, "unable to find correct SOHM index")
+    header = &(table->indexes[index_num]);
+
+    /* Open the heap that this message is in */
+    if(NULL == (fheap = H5HF_open(f, dxpl_id, header->heap_addr)))
+	HGOTO_ERROR(H5E_HEAP, H5E_CANTOPENOBJ, FAIL, "unable to open fractal heap")
+
+    /* Prepare user data for callback */
+    udata.type_id = type_id;
+
+    /* Compute the hash value for the B-tree lookup */
+    if(H5HF_op(fheap, dxpl_id, &(sh_mesg->u.heap_id), H5SM_get_hash_fh_cb, &udata) < 0)
+        HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't access message in fractal heap")
+
+    /* Set up key for message to locate */
+    key.hash = udata.hash;
+    key.encoding = NULL;
+    key.encoding_size = 0;
+    key.fheap = fheap;
+    key.mesg_heap_id = sh_mesg->u.heap_id;
+
+    /* Try to find the message in the index */
+    if(header->index_type == H5SM_LIST) {
+        size_t list_pos;        /* Position of the message in the list */
+
+        /* If the index is stored as a list, get it from the cache */
+        if(NULL == (list = (H5SM_list_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_LIST, header->index_addr, NULL, header, H5AC_READ)))
+	    HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM index")
+
+        /* Find the message in the list */
+        if((list_pos = H5SM_find_in_list(list, &key)) == UFAIL)
+	    HGOTO_ERROR(H5E_SOHM, H5E_NOTFOUND, FAIL, "message not in index")
+
+        /* Copy the message */
+        message = list->messages[list_pos];
+    } /* end if */
+    else /* Index is a B-tree */
+    {
+        HDassert(header->index_type == H5SM_BTREE);
+
+        /* Look up the message in the v2 B-tree */
+        if(H5B2_find(f, dxpl_id, H5SM_INDEX, header->index_addr, &key, H5SM_get_refcount_bt2_cb, &message) < 0)
+	    HGOTO_ERROR(H5E_SOHM, H5E_NOTFOUND, FAIL, "message not in index")
+    } /* end else */
+
+    /* Set the refcount for the message */
+    *ref_count = message.ref_count;
+
+done:
+    /* Release resources */
+    if(list && H5AC_unprotect(f, dxpl_id, H5AC_SOHM_LIST, header->index_addr, list, H5AC__NO_FLAGS_SET) < 0)
+	HDONE_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "unable to close SOHM index")
+    if(table && H5AC_unprotect(f, dxpl_id, H5AC_SOHM_TABLE, f->shared->sohm_addr, table, H5AC__NO_FLAGS_SET) < 0)
+	HDONE_ERROR(H5E_CACHE, H5E_CANTRELEASE, FAIL, "unable to close SOHM master table")
+    if(fheap && H5HF_close(fheap, dxpl_id) < 0)
+        HDONE_ERROR(H5E_HEAP, H5E_CLOSEERROR, FAIL, "can't close fractal heap")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5SM_get_refcount() */
+
diff --git a/src/H5SMpkg.h b/src/H5SMpkg.h
index 1f790fe..e2e839b 100755
--- a/src/H5SMpkg.h
+++ b/src/H5SMpkg.h
@@ -97,24 +97,24 @@
 
 /* Typedef for a SOHM index node */
 typedef struct {
-    uint32_t hash;                /* Hash value for OHM */
-    H5SM_fheap_id_t fheap_id;     /* ID of the OHM in the fractal heap */
-    hsize_t ref_count;            /* Number of times this message is used */
+    uint32_t hash;		/* Hash value for OHM */
+    H5SM_fheap_id_t fheap_id;	/* ID of the OHM in the fractal heap */
+    hsize_t ref_count;		/* Number of times this message is used */
 } H5SM_sohm_t;
 
 typedef enum {
     H5SM_BADTYPE = -1,
-    H5SM_LIST,    /* Index is an unsorted list */
-    H5SM_BTREE    /* Index is a sorted B-tree */
+    H5SM_LIST,    		/* Index is an unsorted list */
+    H5SM_BTREE    		/* Index is a sorted B-tree */
 } H5SM_index_type_t;
 
 /* Typedef for searching an index (list or B-tree) */
 typedef struct {
-    uint32_t hash;    /* The hash value for this message */
-    const void *encoding; /* The message encoded */
-    size_t encoding_size; /* Size of the encoding */
-    H5HF_t *fheap;    /* The heap for this message type, open. */
-    H5SM_fheap_id_t mesg_heap_id; /* The heap_id for this message */
+    uint32_t hash;    			/* The hash value for this message */
+    const void *encoding; 		/* The message encoded */
+    size_t encoding_size; 		/* Size of the encoding */
+    H5HF_t *fheap;    			/* The heap for this message type, open. */
+    H5SM_fheap_id_t mesg_heap_id;	/* The heap_id for this message */
 } H5SM_mesg_key_t;
 
 /* Typedef for a SOHM index header */
@@ -207,8 +207,6 @@ H5_DLL herr_t H5SM_get_hash_fh_cb(const void *obj, size_t obj_len, void *_udata)
 
 /* Testing functions */
 #ifdef H5SM_TESTING
-H5_DLL herr_t H5SM_get_refcount_test(H5F_t *f, hid_t dxpl_id, unsigned type_id,
-    const H5O_shared_t *sh_mesg, hsize_t *ref_count);
 H5_DLL herr_t H5SM_get_mesg_count_test(H5F_t *f, hid_t dxpl_id, unsigned type_id,
     size_t *mesg_count);
 #endif /* H5SM_TESTING */
diff --git a/src/H5SMprivate.h b/src/H5SMprivate.h
index 8d395df..679b59f 100755
--- a/src/H5SMprivate.h
+++ b/src/H5SMprivate.h
@@ -42,6 +42,8 @@ H5_DLL htri_t H5SM_type_shared(H5F_t *f, unsigned type_id, hid_t dxpl_id);
 H5_DLL herr_t H5SM_get_fheap_addr(H5F_t *f, hid_t dxpl_id, unsigned type_id,
     haddr_t *fheap_addr);
 H5_DLL herr_t H5SM_reconstitute(H5O_shared_t *sh_mesg, const uint8_t *heap_id);
+H5_DLL herr_t H5SM_get_refcount(H5F_t *f, hid_t dxpl_id, unsigned type_id,
+    const H5O_shared_t *sh_mesg, hsize_t *ref_count);
 
 #endif /*_H5SMprivate_H*/
 
diff --git a/src/H5SMtest.c b/src/H5SMtest.c
index 20a23e9..36832d3 100644
--- a/src/H5SMtest.c
+++ b/src/H5SMtest.c
@@ -63,139 +63,6 @@
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5SM_get_refcount_bt2_cb
- *
- * Purpose:	v2 B-tree 'find' callback to retrieve the record for a message
- *
- * Return:	SUCCEED/FAIL
- *
- * Programmer:	Quincey Koziol
- *              Tuesday, December 19, 2006
- *
- *-------------------------------------------------------------------------
- */
-static herr_t
-H5SM_get_refcount_bt2_cb(const void *_record, void *_op_data)
-{
-    const H5SM_sohm_t *record = (const H5SM_sohm_t *)_record;  /* v2 B-tree record for message */
-    H5SM_sohm_t *op_data = (H5SM_sohm_t *)_op_data;       /* "op data" from v2 B-tree find */
-
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5SM_get_refcount_bt2_cb)
-
-    /*
-     * Check arguments.
-     */
-    HDassert(record);
-    HDassert(op_data);
-
-    /* Make a copy of the record */
-    *op_data = *record;
-
-    FUNC_LEAVE_NOAPI(SUCCEED)
-} /* end H5SM_get_refcount_bt2_cb() */
-
-
-/*-------------------------------------------------------------------------
- * Function:    H5SM_get_refcount_test
- *
- * Purpose:     Retrieve the reference count for a message
- *
- * Return:      Non-negative on success/Negative on failure
- *
- * Programmer:  Quincey Koziol
- *              Tuesday, December 19, 2006
- *
- *-------------------------------------------------------------------------
- */
-herr_t
-H5SM_get_refcount_test(H5F_t *f, hid_t dxpl_id, unsigned type_id,
-    const H5O_shared_t *sh_mesg, hsize_t *ref_count)
-{    
-    H5HF_t *fheap = NULL;               /* Fractal heap that contains shared messages */
-    H5SM_master_table_t *table = NULL;  /* SOHM master table */
-    H5SM_list_t *list = NULL;           /* SOHM index list for message type (if in list form) */
-    H5SM_index_header_t *header=NULL;   /* Index header for message type */
-    H5SM_mesg_key_t key;                /* Key for looking up message */
-    H5SM_fh_ud_gh_t udata;              /* User data for fractal heap 'op' callback */
-    H5SM_sohm_t message;                /* Record for shared message */
-    ssize_t index_num;                  /* Table index for message type */
-    herr_t ret_value = SUCCEED;         /* Return value */
-
-    FUNC_ENTER_NOAPI_NOINIT(H5SM_get_refcount_test)
-
-    /* Sanity check */
-    HDassert(f);
-    HDassert(sh_mesg);
-    HDassert(ref_count);
-
-    /* Look up the master SOHM table */
-    if(NULL == (table = (H5SM_master_table_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_TABLE, f->shared->sohm_addr, NULL, NULL, H5AC_READ)))
-	HGOTO_ERROR(H5E_CACHE, H5E_CANTPROTECT, FAIL, "unable to load SOHM master table")
-
-    /* Find the correct index and try to delete from it */
-    if((index_num = H5SM_get_index(table, type_id)) < 0)
-	HGOTO_ERROR(H5E_SOHM, H5E_NOTFOUND, FAIL, "unable to find correct SOHM index")
-    header = &(table->indexes[index_num]);
-
-    /* Open the heap that this message is in */
-    if(NULL == (fheap = H5HF_open(f, dxpl_id, header->heap_addr)))
-	HGOTO_ERROR(H5E_HEAP, H5E_CANTOPENOBJ, FAIL, "unable to open fractal heap")
-
-    /* Prepare user data for callback */
-    udata.type_id = type_id;
-
-    /* Compute the hash value for the B-tree lookup */
-    if(H5HF_op(fheap, dxpl_id, &(sh_mesg->u.heap_id), H5SM_get_hash_fh_cb, &udata) < 0)
-        HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, FAIL, "can't access message in fractal heap")
-
-    /* Set up key for message to locate */
-    key.hash = udata.hash;
-    key.encoding = NULL;
-    key.encoding_size = 0;
-    key.fheap = fheap;
-    key.mesg_heap_id = sh_mesg->u.heap_id;
-
-    /* Try to find the message in the index */
-    if(header->index_type == H5SM_LIST) {
-        size_t list_pos;        /* Position of the message in the list */
-
-        /* If the index is stored as a list, get it from the cache */
-        if(NULL == (list = (H5SM_list_t *)H5AC_protect(f, dxpl_id, H5AC_SOHM_LIST, header->index_addr, NULL, header, H5AC_READ)))
-	    HGOTO_ERROR(H5E_SOHM, H5E_CANTPROTECT, FAIL, "unable to load SOHM index")
-
-        /* Find the message in the list */
-        if((list_pos = H5SM_find_in_list(list, &key)) == UFAIL)
-	    HGOTO_ERROR(H5E_SOHM, H5E_NOTFOUND, FAIL, "message not in index")
-
-        /* Copy the message */
-        message = list->messages[list_pos];
-    } /* end if */
-    else /* Index is a B-tree */
-    {
-        HDassert(header->index_type == H5SM_BTREE);
-
-        /* Look up the message in the v2 B-tree */
-        if(H5B2_find(f, dxpl_id, H5SM_INDEX, header->index_addr, &key, H5SM_get_refcount_bt2_cb, &message) < 0)
-	    HGOTO_ERROR(H5E_SOHM, H5E_NOTFOUND, FAIL, "message not in index")
-    } /* end else */
-
-    /* Set the refcount for the message */
-    *ref_count = message.ref_count;
-
-done:
-    /* Release resources */
-    if(list && H5AC_unprotect(f, dxpl_id, H5AC_SOHM_LIST, header->index_addr, list, H5AC__NO_FLAGS_SET) < 0)
-	HDONE_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "unable to close SOHM index")
-    if(table && H5AC_unprotect(f, dxpl_id, H5AC_SOHM_TABLE, f->shared->sohm_addr, table, H5AC__NO_FLAGS_SET) < 0)
-	HDONE_ERROR(H5E_CACHE, H5E_CANTRELEASE, FAIL, "unable to close SOHM master table")
-    if(fheap && H5HF_close(fheap, dxpl_id) < 0)
-        HDONE_ERROR(H5E_HEAP, H5E_CLOSEERROR, FAIL, "can't close fractal heap")
-
-    FUNC_LEAVE_NOAPI(ret_value)
-} /* end H5SM_get_refcount_test() */
-
-
-/*-------------------------------------------------------------------------
  * Function:    H5SM_get_mesg_count_test
  *
  * Purpose:     Retrieve the number of messages tracked of a certain type
diff --git a/src/H5Tcommit.c b/src/H5Tcommit.c
index 7415342..6ed7856 100644
--- a/src/H5Tcommit.c
+++ b/src/H5Tcommit.c
@@ -406,8 +406,7 @@ H5T_link(const H5T_t *type, int adjust, hid_t dxpl_id)
 {
     int ret_value;      /* Return value */
 
-    /* Use no-init for efficiency */
-    FUNC_ENTER_NOAPI(H5T_link,FAIL)
+    FUNC_ENTER_NOAPI(H5T_link, FAIL)
 
     HDassert(type);
     HDassert(type->sh_loc.flags & H5O_COMMITTED_FLAG);
diff --git a/src/H5Tpkg.h b/src/H5Tpkg.h
index f8f03dc..14f77cf 100644
--- a/src/H5Tpkg.h
+++ b/src/H5Tpkg.h
@@ -41,7 +41,6 @@
 #include "H5Fprivate.h"		/* Files				*/
 #include "H5FLprivate.h"	/* Free Lists				*/
 #include "H5Oprivate.h"		/* Object headers		  	*/
-#include "H5SMprivate.h"	/* Shared Messages			*/
 
 /* Other public headers needed by this file */
 #include "H5Spublic.h"		/* Dataspace functions			*/