[svn-r13058] Description:

    Clean up some shared message operations and other minor tweaks, in the
process of trying to solve the messy way that shared object header messages
are implemented in general (not James' work - which is fine :-)

Tested on:
    Mac OS X/32 10.4.8 (amazon)
    FreeBSD/32 4.11 (sleipnir)
    AIX/32 5.? (copper)

1 files changed, 23 insertions, 12 deletions

diff --git a/src/H5Oshared.c b/src/H5Oshared.c
index 07e5489..963e8f4 100644
--- a/src/H5Oshared.c
+++ b/src/H5Oshared.c
@@ -32,6 +32,7 @@
 #include "H5private.h"		/* Generic Functions			*/
 #include "H5Eprivate.h"		/* Error handling		  	*/
 #include "H5Fpkg.h"             /* File access				*/
+#include "H5FLprivate.h"	/* Free lists                           */
 #include "H5Gprivate.h"		/* Groups				*/
 #include "H5HFprivate.h"        /* Fractal heap				*/
 #include "H5MMprivate.h"	/* Memory management			*/
@@ -83,6 +84,12 @@ const H5O_msg_class_t H5O_MSG_SHARED[1] = {{
 #define H5O_SHARED_VERSION_3	3
 #define H5O_SHARED_VERSION	H5O_SHARED_VERSION_3
 
+/* Size of stack buffer for serialized messages */
+#define H5O_MESG_BUF_SIZE               128
+
+/* Declare a free list to manage the serialized message information */
+H5FL_BLK_DEFINE(ser_mesg);
+
 
 /*-------------------------------------------------------------------------
  * Function:	H5O_shared_read
@@ -108,7 +115,8 @@ H5O_shared_read(H5F_t *f, hid_t dxpl_id, const H5O_shared_t *shared,
     const H5O_msg_class_t *type, void *mesg)
 {
     H5HF_t *fheap = NULL;
-    unsigned char *buf = NULL;  /* Pointer to raw message in heap */
+    uint8_t mesg_buf[H5O_MESG_BUF_SIZE]; /* Buffer for deserializing messages */
+    uint8_t *buf = NULL;        /* Pointer to raw message in heap */
     void *native_mesg = NULL;   /* Used for messages shared in heap */
     void *ret_value = NULL;     /* Return value */
 
@@ -132,23 +140,27 @@ H5O_shared_read(H5F_t *f, hid_t dxpl_id, const H5O_shared_t *shared,
 
         /* Retrieve the fractal heap address for shared messages */
         if((fheap_addr = H5SM_get_fheap_addr(f, type->id, dxpl_id)) == HADDR_UNDEF)
-            HGOTO_ERROR(H5E_SOHM, H5E_CANTGET, NULL, "can't get fheap address for shared messages")
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, NULL, "can't get fheap address for shared messages")
 
         /* Open the fractal heap */
         if(NULL == (fheap = H5HF_open(f, dxpl_id, fheap_addr)))
-            HGOTO_ERROR(H5E_HEAP, H5E_CANTOPENOBJ, NULL, "unable to open fractal heap")
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTOPENOBJ, NULL, "unable to open fractal heap")
 
         /* Get the size of the message in the heap */
         if(H5HF_get_obj_len(fheap, dxpl_id, &(shared->u.heap_id), &buf_size) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_CANTGET, NULL, "can't get message size from fractal heap.")
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, NULL, "can't get message size from fractal heap.")
 
-        /* Allocate buffer */
-        if(NULL == (buf = H5MM_malloc(buf_size)))
-            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
+        /* Allocate space for serialized message, if necessary */
+        if(buf_size > sizeof(mesg_buf)) {
+            if(NULL == (buf = H5FL_BLK_MALLOC(ser_mesg, buf_size)))
+                HGOTO_ERROR(H5E_OHDR, H5E_NOSPACE, NULL, "memory allocation failed")
+        } /* end if */
+        else
+            buf = mesg_buf;
 
         /* Retrieve the message from the heap */
         if(H5HF_read(fheap, dxpl_id, &(shared->u.heap_id), buf) < 0)
-            HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "can't read message from fractal heap.")
+            HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, NULL, "can't read message from fractal heap.")
 
         /* Decode the message */
         if(NULL == (native_mesg = H5O_msg_decode(f, dxpl_id, type->id, buf)))
@@ -171,12 +183,11 @@ H5O_shared_read(H5F_t *f, hid_t dxpl_id, const H5O_shared_t *shared,
         HGOTO_ERROR(H5E_OHDR, H5E_CANTINIT, NULL, "unable to set sharing information")
 
 done:
-    if(buf)
-        H5MM_xfree(buf);
-
+    /* Release resources */
+    if(buf && buf != mesg_buf)
+        H5FL_BLK_FREE(ser_mesg, buf);
     if(native_mesg)
         H5O_msg_free(type->id, native_mesg);
-
     if(fheap && H5HF_close(fheap, dxpl_id) < 0)
         HDONE_ERROR(H5E_HEAP, H5E_CANTFREE, NULL, "can't close fractal heap")