[svn-r13245] Added "superblock extension" object header to hold shared object header

information, rather than storing it directly in the superblock.
This should make future updates to the superblock much less painful.

Tested on Windows, kagiso, and smirom.

1 files changed, 15 insertions, 0 deletions

diff --git a/src/H5Oprivate.h b/src/H5Oprivate.h
index 4a9dc95..a3df7fb 100644
--- a/src/H5Oprivate.h
+++ b/src/H5Oprivate.h
@@ -69,6 +69,8 @@ typedef struct H5O_t H5O_t;
 #define H5O_MSG_FLAG_CONSTANT	0x01u
 #define H5O_MSG_FLAG_SHARED	0x02u
 #define H5O_MSG_FLAG_DONTSHARE	0x04u
+#define H5O_MSG_FLAG_FAIL_IF_UNKNOWN 0x08u
+#define H5O_MSG_FLAG_CURRENT 0x10u
 #define H5O_MSG_FLAG_BITS	(H5O_MSG_FLAG_CONSTANT|H5O_MSG_FLAG_SHARED|H5O_MSG_FLAG_DONTSHARE)
 
 /* Flags for updating messages */
@@ -132,6 +134,7 @@ typedef struct H5O_copy_t {
 #define H5O_CONT_ID	0x0010          /* Object header continuation message.  */
 #define H5O_STAB_ID	0x0011          /* Symbol table message.  */
 #define H5O_MTIME_NEW_ID 0x0012         /* Modification time message. (New)  */
+#define H5O_SHMESG_ID   0x0013          /* Shared message "SOHM" table. */
 
 
 /* Shared object message flags.
@@ -369,6 +372,18 @@ typedef struct H5O_stab_t {
     haddr_t	heap_addr;		/*address of name heap		     */
 } H5O_stab_t;
 
+/*
+ * Shared message table message
+ * Information about file-wide shared message table, stored in superblock
+ * extension
+ * (Data structure in memory)
+ */
+typedef struct H5O_shmesg_table_t {
+    haddr_t		addr;	        /*file address of SOHM table */
+    unsigned		version;	/*SOHM table version number */
+    unsigned		nindexes;	/*number of indexes in the table */
+} H5O_shmesg_table_t;
+
 /* Typedef for iteration operations */
 typedef herr_t (*H5O_operator_t)(const void *mesg/*in*/, unsigned idx,
     void *operator_data/*in,out*/);