[svn-r19123] Description:

	Converge code on "metadata journaling merge" branch to be closer to
code on current trunk:
	- Updates to internal error reporting macros
	- Updated routines to operation on superblock extension
	- Object header query operations

	Misc. minor updates to caching code.

Tested on:
        FreeBSD/32 6.3 (duty) in debug mode
        FreeBSD/64 6.3 (liberty) w/C++ & FORTRAN, in debug mode
        Linux/32 2.6 (jam) w/PGI compilers, w/default API=1.8.x,
                w/C++ & FORTRAN, w/threadsafe, in debug mode
        Linux/64-amd64 2.6 (amani) w/Intel compilers, w/default API=1.6.x,
                w/C++ & FORTRAN, in production mode
        Solaris/32 2.10 (linew) w/deprecated symbols disabled, w/C++ & FORTRAN,
                w/szip filter, w/threadsafe, in production mode
        Linux/PPC 2.6 (heiwa) w/C++ & FORTRAN, w/threadsafe, in debug mode
        Linux/64-ia64 2.6 (cobalt) w/Intel compilers, w/C++ & FORTRAN,
                in production mode
        Linux/64-amd64 2.6 (abe) w/parallel, w/FORTRAN, in debug mode
        Mac OS X/32 10.6.4 (amazon) in debug mode
        Mac OS X/32 10.6.4 (amazon) w/C++ & FORTRAN, w/threadsafe,
                in production mode
        Mac OS X/32 10.6.4 (amazon) w/parallel, in debug mode

9 files changed, 552 insertions, 120 deletions

diff --git a/src/H5AC.c b/src/H5AC.c
index fd2df15..48b6635 100644
--- a/src/H5AC.c
+++ b/src/H5AC.c
@@ -1741,7 +1741,7 @@ H5AC_unprotect(H5F_t *f, hid_t dxpl_id, const H5AC_class_t *type, haddr_t addr,
             HGOTO_ERROR(H5E_CACHE, H5E_CANTUNPROTECT, FAIL, "can't log dirtied entry")
     }
 
-    if ( ( (flags & H5C__DELETED_FLAG) != 0 ) &&
+    if ( ( deleted ) &&
          ( NULL != (aux_ptr = f->shared->cache->aux_ptr) ) &&
          ( aux_ptr->mpi_rank == 0 ) ) {
 
diff --git a/src/H5C.c b/src/H5C.c
index cedc461..f60e0f6 100644
--- a/src/H5C.c
+++ b/src/H5C.c
@@ -223,7 +223,6 @@ H5C_epoch_marker_load(H5F_t UNUSED * f,
     HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, NULL, "called unreachable fcn.")
 
 done:
-
     FUNC_LEAVE_NOAPI(ret_value)
 }
 
@@ -242,7 +241,6 @@ H5C_epoch_marker_flush(H5F_t UNUSED *f,
     HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "called unreachable fcn.")
 
 done:
-
     FUNC_LEAVE_NOAPI(ret_value)
 }
 
@@ -257,7 +255,6 @@ H5C_epoch_marker_dest(H5F_t UNUSED * f,
     HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "called unreachable fcn.")
 
 done:
-
     FUNC_LEAVE_NOAPI(ret_value)
 }
 
@@ -273,7 +270,6 @@ H5C_epoch_marker_clear(H5F_t UNUSED * f,
     HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "called unreachable fcn.")
 
 done:
-
     FUNC_LEAVE_NOAPI(ret_value)
 }
 
@@ -289,7 +285,6 @@ H5C_epoch_marker_size(const H5F_t UNUSED * f,
     HGOTO_ERROR(H5E_CACHE, H5E_SYSTEM, FAIL, "called unreachable fcn.")
 
 done:
-
     FUNC_LEAVE_NOAPI(ret_value)
 }
 
diff --git a/src/H5Eint.c b/src/H5Eint.c
index e0fa482..92c36a4 100644
--- a/src/H5Eint.c
+++ b/src/H5Eint.c
@@ -660,6 +660,107 @@ H5E_set_auto(H5E_t *estack, const H5E_auto_op_t *op, void *client_data)
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5E_printf_stack
+ *
+ * Purpose:	Printf-like wrapper around H5E_push_stack.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		Tuesday, August 12, 2008
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5E_printf_stack(H5E_t *estack, const char *file, const char *func, unsigned line,
+    hid_t cls_id, hid_t maj_id, hid_t min_id, const char *fmt, ...)
+{
+    va_list     ap;                     /* Varargs info */
+#ifndef H5_HAVE_VASPRINTF
+    int         tmp_len;        /* Current size of description buffer */
+    int         desc_len;       /* Actual length of description when formatted */
+#endif /* H5_HAVE_VASPRINTF */
+    char        *tmp = NULL;      /* Buffer to place formatted description in */
+    herr_t	ret_value = SUCCEED;    /* Return value */
+
+    /*
+     * WARNING: We cannot call HERROR() from within this function or else we
+     *		could enter infinite recursion.  Furthermore, we also cannot
+     *		call any other HDF5 macro or function which might call
+     *		HERROR().  HERROR() is called by HRETURN_ERROR() which could
+     *		be called by FUNC_ENTER().
+     */
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5E_printf_stack)
+
+    /* Sanity check */
+    HDassert(cls_id > 0);
+    HDassert(maj_id > 0);
+    HDassert(min_id > 0);
+    HDassert(fmt);
+
+/* Note that the variable-argument parsing for the format is identical in
+ *      the H5Epush2() routine - correct errors and make changes in both
+ *      places. -QAK
+ */
+
+    /* Start the variable-argument parsing */
+    va_start(ap, fmt);
+
+#ifdef H5_HAVE_VASPRINTF
+    /* Use the vasprintf() routine, since it does what we're trying to do below */
+    if(HDvasprintf(&tmp, fmt, ap) < 0)
+        HGOTO_DONE(FAIL)
+#else /* H5_HAVE_VASPRINTF */
+    /* Allocate space for the formatted description buffer */
+    tmp_len = 128;
+    if(NULL == (tmp = H5MM_malloc((size_t)tmp_len)))
+        HGOTO_DONE(FAIL)
+
+    /* If the description doesn't fit into the initial buffer size, allocate more space and try again */
+    while((desc_len = HDvsnprintf(tmp, (size_t)tmp_len, fmt, ap))
+#ifdef H5_VSNPRINTF_WORKS
+            >
+#else /* H5_VSNPRINTF_WORKS */
+            >=
+#endif /* H5_VSNPRINTF_WORKS */
+            (tmp_len - 1)
+#ifndef H5_VSNPRINTF_WORKS
+            || (desc_len < 0)
+#endif /* H5_VSNPRINTF_WORKS */
+            ) {
+        /* shutdown & restart the va_list */
+        va_end(ap);
+        va_start(ap, fmt);
+
+        /* Release the previous description, it's too small */
+        H5MM_xfree(tmp);
+
+        /* Allocate a description of the appropriate length */
+#ifdef H5_VSNPRINTF_WORKS
+        tmp_len = desc_len + 1;
+#else /* H5_VSNPRINTF_WORKS */
+        tmp_len = 2 * tmp_len;
+#endif /* H5_VSNPRINTF_WORKS */
+        if(NULL == (tmp = H5MM_malloc((size_t)tmp_len)))
+            HGOTO_DONE(FAIL)
+    } /* end while */
+#endif /* H5_HAVE_VASPRINTF */
+
+    va_end(ap);
+
+    /* Push the error on the stack */
+    if(H5E_push_stack(estack, file, func, line, cls_id, maj_id, min_id, tmp) < 0)
+        HGOTO_DONE(FAIL)
+
+done:
+    if(tmp)
+        H5MM_xfree(tmp);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5E_printf_stack() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5E_push_stack
  *
  * Purpose:	Pushes a new error record onto error stack for the current
diff --git a/src/H5Eprivate.h b/src/H5Eprivate.h
index 05ce10e..0f4cb35 100644
--- a/src/H5Eprivate.h
+++ b/src/H5Eprivate.h
@@ -32,14 +32,14 @@ typedef struct H5E_t H5E_t;
  * and a FUNC_LEAVE() within a function body.  The arguments are the major
  * error number, the minor error number, and a description of the error.
  */
-#define HERROR(maj_id, min_id, str) H5E_push_stack(NULL, __FILE__, FUNC, __LINE__, H5E_ERR_CLS_g, maj_id, min_id, str)
+#define HERROR(maj_id, min_id, ...) H5E_printf_stack(NULL, __FILE__, FUNC, __LINE__, H5E_ERR_CLS_g, maj_id, min_id, __VA_ARGS__)
 
 /*
  * HCOMMON_ERROR macro, used by HDONE_ERROR and HGOTO_ERROR
  * (Shouldn't need to be used outside this header file)
  */
-#define HCOMMON_ERROR(maj, min, str)  				              \
-   HERROR(maj, min, str);						      \
+#define HCOMMON_ERROR(maj, min, ...)  				              \
+   HERROR(maj, min, __VA_ARGS__);						      \
    (void)H5E_dump_api_stack((int)H5_IS_API(FUNC));
 
 /*
@@ -51,8 +51,8 @@ typedef struct H5E_t H5E_t;
  * (This macro can also be used to push an error and set the return value
  *      without jumping to any labels)
  */
-#define HDONE_ERROR(maj, min, ret_val, str) {				      \
-   HCOMMON_ERROR(maj, min, str);					      \
+#define HDONE_ERROR(maj, min, ret_val, ...) {				      \
+   HCOMMON_ERROR(maj, min, __VA_ARGS__);					      \
    ret_value = ret_val;                                                       \
 }
 
@@ -63,8 +63,8 @@ typedef struct H5E_t H5E_t;
  * error string.  The return value is assigned to a variable `ret_value' and
  * control branches to the `done' label.
  */
-#define HGOTO_ERROR(maj, min, ret_val, str) {				      \
-   HCOMMON_ERROR(maj, min, str);					      \
+#define HGOTO_ERROR(maj, min, ret_val, ...) {				      \
+   HCOMMON_ERROR(maj, min, __VA_ARGS__);					      \
    HGOTO_DONE(ret_val)						              \
 }
 
@@ -76,13 +76,6 @@ typedef struct H5E_t H5E_t;
  */
 #define HGOTO_DONE(ret_val) {ret_value = ret_val; goto done;}
 
-/* Library-private functions defined in H5E package */
-H5_DLL herr_t H5E_init(void);
-H5_DLL herr_t H5E_push_stack(H5E_t *estack, const char *file, const char *func, unsigned line,
-                            hid_t cls_id, hid_t maj_id, hid_t min_id, const char *desc);
-H5_DLL herr_t H5E_clear_stack(H5E_t *estack);
-H5_DLL herr_t H5E_dump_api_stack(int is_api);
-
 /*
  * Macros handling system error messages as described in C standard.
  * These macros assume errnum is a valid system error code.
@@ -91,16 +84,13 @@ H5_DLL herr_t H5E_dump_api_stack(int is_api);
 /* Retrieve the error code description string and push it onto the error
  * stack.
  */
-#define	HSYS_ERROR(errnum) {						      \
-    HERROR(H5E_INTERNAL, H5E_SYSERRSTR, HDstrerror(errnum));                  \
-}
 #define	HSYS_DONE_ERROR(majorcode, minorcode, retcode, str) {		      \
-    HSYS_ERROR(errno);							      \
-    HDONE_ERROR(majorcode, minorcode, retcode, str);			      \
+    int myerrno = errno;							      \
+    HDONE_ERROR(majorcode, minorcode, retcode, "%s, errno = %d, error message = '%s'", str, myerrno, HDstrerror(myerrno));			      \
 }
 #define	HSYS_GOTO_ERROR(majorcode, minorcode, retcode, str) {		      \
-    HSYS_ERROR(errno);							      \
-    HGOTO_ERROR(majorcode, minorcode, retcode, str);			      \
+    int myerrno = errno;							      \
+    HGOTO_ERROR(majorcode, minorcode, retcode, "%s, errno = %d, error message = '%s'", str, myerrno, HDstrerror(myerrno));			      \
 }
 
 #ifdef H5_HAVE_PARALLEL
@@ -125,5 +115,14 @@ extern	int	H5E_mpi_error_str_len;
 }
 #endif /* H5_HAVE_PARALLEL */
 
+/* Library-private functions defined in H5E package */
+H5_DLL herr_t H5E_init(void);
+H5_DLL herr_t H5E_push_stack(H5E_t *estack, const char *file, const char *func,
+    unsigned line, hid_t cls_id, hid_t maj_id, hid_t min_id, const char *desc);
+H5_DLL herr_t H5E_printf_stack(H5E_t *estack, const char *file, const char *func,
+    unsigned line, hid_t cls_id, hid_t maj_id, hid_t min_id, const char *fmt, ...);
+H5_DLL herr_t H5E_clear_stack(H5E_t *estack);
+H5_DLL herr_t H5E_dump_api_stack(int is_api);
+
 #endif /* _H5Eprivate_H */
 
diff --git a/src/H5Fpkg.h b/src/H5Fpkg.h
index 070d361..387c96f 100644
--- a/src/H5Fpkg.h
+++ b/src/H5Fpkg.h
@@ -181,8 +181,11 @@ H5_DLL herr_t H5F_mount_count_ids(H5F_t *f, unsigned *nopen_files, unsigned *nop
 H5_DLL herr_t H5F_super_init(H5F_t *f, hid_t dxpl_id);
 H5_DLL herr_t H5F_super_write(H5F_t *f, hid_t dxpl_id);
 H5_DLL herr_t H5F_super_read(H5F_t *f, hid_t dxpl_id, H5G_loc_t *root_loc);
-H5_DLL herr_t H5F_super_ext_size(H5F_t *f, hid_t dxpl_id, hsize_t *super_ext_info);
 
+/* Superblock extension related routines */
+H5_DLL herr_t H5F_super_ext_size(H5F_t *f, hid_t dxpl_id, hsize_t *super_ext_info);
+H5_DLL herr_t H5F_super_ext_write_msg(H5F_t *f, hid_t dxpl_id, void *mesg, unsigned id, hbool_t may_create);
+H5_DLL herr_t H5F_super_ext_remove_msg(H5F_t *f, hid_t dxpl_id, unsigned id);
 
 /* Shared file list related routines */
 H5_DLL herr_t H5F_sfile_add(H5F_file_t *shared);
diff --git a/src/H5Fsuper.c b/src/H5Fsuper.c
index 6e5b940..b01e849 100644
--- a/src/H5Fsuper.c
+++ b/src/H5Fsuper.c
@@ -108,6 +108,9 @@
 /********************/
 /* Local Prototypes */
 /********************/
+static herr_t H5F_super_ext_create(H5F_t *f, hid_t dxpl_id, H5O_loc_t *ext_ptr);
+static herr_t H5F_super_ext_open(H5F_t *f, haddr_t ext_addr, H5O_loc_t *ext_ptr);
+static herr_t H5F_super_ext_close(H5F_t *f, H5O_loc_t *ext_ptr);
 
 
 /*********************/
@@ -213,6 +216,139 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:    H5F_super_ext_create
+ *
+ * Purpose:     Create the superblock extension
+ *
+ * Return:      Success:        non-negative on success
+ *              Failure:        Negative
+ *
+ * Programmer:  Vailin Choi; Feb 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5F_super_ext_create(H5F_t *f, hid_t dxpl_id, H5O_loc_t *ext_ptr)
+{
+    H5P_genplist_t *plist;                      /* File creation property list */
+    unsigned        super_vers;                 /* Superblock version              */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5F_super_ext_create)
+
+    /* Sanity check */
+    HDassert(f);
+    HDassert(f->shared);
+    HDassert(ext_ptr);
+
+    /* Get the shared file creation property list */
+    if(NULL == (plist = H5I_object(f->shared->fcpl_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a property list")
+
+    /* Grab values from property list */
+    if(H5P_get(plist, H5F_CRT_SUPER_VERS_NAME, &super_vers) < 0)
+        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "unable to get superblock version")
+
+    /* Check for older version of superblock format */
+    if(super_vers < HDF5_SUPERBLOCK_VERSION_2)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTCREATE, FAIL, "superblock extension not permitted?!?!")
+    else if(f->shared->extension_addr != HADDR_UNDEF)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTCREATE, FAIL, "superblock extension already exists?!?!")
+    else {
+        /* The superblock extension isn't actually a group, but the
+         * default group creation list should work fine.
+         * If we don't supply a size for the object header, HDF5 will
+         * allocate H5O_MIN_SIZE by default.  This is currently
+         * big enough to hold the biggest possible extension, but should
+         * be tuned if more information is added to the superblock
+         * extension.
+         */
+        H5O_loc_reset(ext_ptr);
+        if(H5O_create(f, dxpl_id, 0, H5P_GROUP_CREATE_DEFAULT, ext_ptr) < 0)
+    	HGOTO_ERROR(H5E_OHDR, H5E_CANTCREATE, FAIL, "unable to create superblock extension")
+
+        /* Record the address of the superblock extension */
+        f->shared->extension_addr = ext_ptr->addr;
+    } /* end else */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5F_super_ext_create() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5F_super_ext_open
+ *
+ * Purpose:     Open an existing superblock extension
+ *
+ * Return:      Success:        non-negative on success
+ *              Failure:        Negative
+ *
+ * Programmer:  Vailin Choi; Feb 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5F_super_ext_open(H5F_t *f, haddr_t ext_addr, H5O_loc_t *ext_ptr)
+{
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5F_super_ext_open)
+
+    /* Sanity check */
+    HDassert(f);
+    HDassert(H5F_addr_defined(ext_addr));
+    HDassert(ext_ptr);
+
+    /* Set up "fake" object location for superblock extension */
+    H5O_loc_reset(ext_ptr);
+    ext_ptr->file = f;
+    ext_ptr->addr = ext_addr;
+
+    /* Open the superblock extension object header */
+    if(H5O_open(ext_ptr) < 0)
+	HGOTO_ERROR(H5E_OHDR, H5E_CANTOPENOBJ, FAIL, "unable to open superblock extension")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5F_super_ext_open() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:   H5F_super_ext_close
+ *
+ * Purpose:    Close superblock extension
+ *
+ * Return:     Success:        non-negative on success
+ *             Failure:        Negative
+ *
+ * Programmer:  Vailin Choi; Feb 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5F_super_ext_close(H5F_t *f, H5O_loc_t *ext_ptr)
+{
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5F_super_ext_close)
+
+    /* Sanity check */
+    HDassert(f);
+    HDassert(ext_ptr);
+
+    /* Twiddle the number of open objects to avoid closing the file. */
+    f->nopen_objs++;
+    if(H5O_close(ext_ptr) < 0)
+        HGOTO_ERROR(H5E_FILE, H5E_CANTCLOSEOBJ, FAIL, "unable to close superblock extension")
+    f->nopen_objs--;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5F_super_ext_close() */
+
+
+/*-------------------------------------------------------------------------
  * Function:    H5F_super_read
  *
  * Purpose:     Reads the superblock from the file or from the BUF. If
@@ -560,14 +696,9 @@ H5F_super_read(H5F_t *f, hid_t dxpl_id, H5G_loc_t *root_loc)
          */
         HDassert(super_vers >= HDF5_SUPERBLOCK_VERSION_2);
 
-        /* Set up "fake" object location for superblock extension */
-        H5O_loc_reset(&ext_loc);
-        ext_loc.file = f;
-        ext_loc.addr = shared->extension_addr;
-
         /* Open the superblock extension */
-        if(H5O_open(&ext_loc) < 0)
-            HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, FAIL, "unable to open superblock extension")
+	if(H5F_super_ext_open(f, shared->extension_addr, &ext_loc) < 0)
+            HGOTO_ERROR(H5E_FILE, H5E_CANTOPENOBJ, FAIL, "unable to open file's superblock extension")
 
         /* Read in the shared OH message information if there is any */
         if(H5SM_get_info(&ext_loc, c_plist, dxpl_id) < 0)
@@ -618,13 +749,9 @@ H5F_super_read(H5F_t *f, hid_t dxpl_id, H5G_loc_t *root_loc)
             H5O_msg_reset(H5O_DRVINFO_ID, &drvinfo);
         } /* end else */
 
-        /* Close the extension.  Twiddle the number of open objects to avoid
-         * closing the file (since this will be the only open object).
-         */
-        f->nopen_objs++;
-        if(H5O_close(&ext_loc) < 0)
-            HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, FAIL, "unable to close superblock extension")
-        f->nopen_objs--;
+        /* Close superblock extension */
+	if(H5F_super_ext_close(f, &ext_loc) < 0)
+	    HGOTO_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "unable to close file's superblock extension")
     } /* end if */
 
 done:
@@ -754,13 +881,9 @@ H5F_super_init(H5F_t *f, hid_t dxpl_id)
          * be tuned if more information is added to the superblock
          * extension.
          */
-        H5O_loc_reset(&ext_loc);
-        if(H5O_create(f, dxpl_id, 0, H5P_GROUP_CREATE_DEFAULT, &ext_loc) < 0)
+	if(H5F_super_ext_create(f, dxpl_id, &ext_loc) < 0)
             HGOTO_ERROR(H5E_FILE, H5E_CANTCREATE, FAIL, "unable to create superblock extension")
 
-        /* Record the address of the superblock extension */
-        f->shared->extension_addr = ext_loc.addr;
-
         /* Create the Shared Object Header Message table and register it with
          *      the metadata cache, if this file supports shared messages.
          */
@@ -803,13 +926,9 @@ H5F_super_init(H5F_t *f, hid_t dxpl_id)
                 HGOTO_ERROR(H5E_FILE, H5E_CANTINIT, FAIL, "unable to update driver info header message")
         } /* end if */
 
-        /* Twiddle the number of open objects to avoid closing the file
-         * (since this will be the only open object currently).
-         */
-        f->nopen_objs++;
-        if(H5O_close(&ext_loc) < 0)
-            HGOTO_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "unable to close superblock extension")
-        f->nopen_objs--;
+        /* Close superblock extension */
+	if(H5F_super_ext_close(f, &ext_loc) < 0)
+	    HGOTO_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "unable to close file's superblock extension")
     } /* end if */
 
 done:
@@ -1008,3 +1127,135 @@ done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* H5F_super_ext_size() */
 
+
+/*-------------------------------------------------------------------------
+ * Function:    H5F_super_ext_write_msg()
+ *
+ * Purpose:     Write the message with ID to the superblock extension
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Vailin Choi; Feb 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5F_super_ext_write_msg(H5F_t *f, hid_t dxpl_id, void *mesg, unsigned id, hbool_t may_create)
+{
+    H5O_loc_t 	ext_loc; 	/* "Object location" for superblock extension */
+    htri_t 	status;       	/* Indicate whether the message exists or not */
+    herr_t 	ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(H5F_super_ext_write_msg, FAIL)
+
+    /* Sanity checks */
+    HDassert(f);
+    HDassert(f->shared);
+    HDassert(f->shared->extension_addr);
+
+    /* Open/create the superblock extension object header */
+    if(H5F_addr_defined(f->shared->extension_addr)) {
+	if(H5F_super_ext_open(f, f->shared->extension_addr, &ext_loc) < 0)
+	    HGOTO_ERROR(H5E_FILE, H5E_CANTOPENOBJ, FAIL, "unable to open file's superblock extension")
+    } /* end if */
+    else {
+        HDassert(may_create);
+	if(H5F_super_ext_create(f, dxpl_id, &ext_loc) < 0)
+	    HGOTO_ERROR(H5E_FILE, H5E_CANTCREATE, FAIL, "unable to create file's superblock extension")
+    } /* end else */
+    HDassert(H5F_addr_defined(ext_loc.addr));
+
+    /* Check if message with ID does not exist in the object header */
+    if((status = H5O_msg_exists(&ext_loc, id, dxpl_id)) < 0)
+	HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "unable to check object header for message or message exists")
+
+    /* Check for creating vs. writing */
+    if(may_create) {
+	if(status)
+	    HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "Message should not exist")
+
+	/* Create the message with ID in the superblock extension */
+	if(H5O_msg_create(&ext_loc, id, H5O_MSG_FLAG_DONTSHARE, H5O_UPDATE_TIME, mesg, dxpl_id) < 0)
+	    HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "unable to create the message in object header")
+    } /* end if */
+    else {
+	if(!status)
+	    HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "Message should exist")
+
+	/* Update the message with ID in the superblock extension */
+	if(H5O_msg_write(&ext_loc, id, H5O_MSG_FLAG_DONTSHARE, H5O_UPDATE_TIME, mesg, dxpl_id) < 0)
+	    HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "unable to write the message in object header")
+    } /* end else */
+
+    /* Close the superblock extension object header */
+    if(H5F_super_ext_close(f, &ext_loc) < 0)
+	HGOTO_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "unable to close file's superblock extension")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5F_super_ext_write_msg() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:    H5F_super_ext_remove_msg
+ *
+ * Purpose:     Remove the message with ID from the superblock extension
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ * Programmer:  Vailin Choi; Feb 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5F_super_ext_remove_msg(H5F_t *f, hid_t dxpl_id, unsigned id)
+{
+    htri_t 	status;       	/* Indicate whether the message exists or not */
+    H5O_loc_t 	ext_loc; 	/* "Object location" for superblock extension */
+    int		null_count = 0;	/* # of null messages */
+    herr_t 	ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(H5F_super_ext_remove_msg, FAIL)
+
+    /* Make sure that the superblock extension object header exists */
+    HDassert(H5F_addr_defined(f->shared->extension_addr));
+
+    /* Open superblock extension object header */
+    if(H5F_super_ext_open(f, f->shared->extension_addr, &ext_loc) < 0)
+	HGOTO_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "error in starting file's superblock extension")
+
+    /* Check if message with ID exists in the object header */
+    if((status = H5O_msg_exists(&ext_loc, id, dxpl_id)) < 0)
+	HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "unable to check object header for message")
+    else if(status) { /* message exists */
+	H5O_hdr_info_t 	hdr_info;       /* Object header info for superblock extension */
+
+	/* Remove the message */
+	if(H5O_msg_remove(&ext_loc, id, H5O_ALL, TRUE, dxpl_id) < 0)
+	    HGOTO_ERROR(H5E_OHDR, H5E_CANTDELETE, FAIL, "unable to delete free-space manager info message")
+
+	/* Get info for the superblock extension's object header */
+	if(H5O_get_hdr_info(&ext_loc, dxpl_id, &hdr_info) < 0)
+	    HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "unable to retrieve superblock extension info")
+
+	/* If the object header is an empty base chunk, remove superblock extension */
+	if(hdr_info.nchunks == 1) {
+	    if((null_count = H5O_msg_count(&ext_loc, H5O_NULL_ID, dxpl_id)) < 0)
+		HGOTO_ERROR(H5E_SYM, H5E_CANTCOUNT, FAIL, "unable to count messages")
+	    else if((unsigned)null_count == hdr_info.nmesgs) {
+		HDassert(H5F_addr_defined(ext_loc.addr));
+		if(H5O_delete(f, dxpl_id, ext_loc.addr) < 0)
+		    HGOTO_ERROR(H5E_SYM, H5E_CANTCOUNT, FAIL, "unable to count messages")
+		f->shared->extension_addr = HADDR_UNDEF;
+	    } /* end if */
+	} /* end if */
+    } /* end if */
+
+    /* Close superblock extension object header */
+    if(H5F_super_ext_close(f, &ext_loc) < 0)
+	HGOTO_ERROR(H5E_FILE, H5E_CANTRELEASE, FAIL, "unable to close file's superblock extension")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5F_super_ext_remove_msg() */
+
diff --git a/src/H5O.c b/src/H5O.c
index 86997fe..e22f36f 100644
--- a/src/H5O.c
+++ b/src/H5O.c
@@ -84,6 +84,7 @@ static herr_t H5O_obj_type_real(H5O_t *oh, H5O_type_t *obj_type);
 static herr_t H5O_visit(hid_t loc_id, const char *obj_name, H5_index_t idx_type,
     H5_iter_order_t order, H5O_iterate_t op, void *op_data, hid_t lapl_id,
     hid_t dxpl_id);
+static herr_t H5O_get_hdr_info_real(const H5O_t *oh, H5O_hdr_info_t *hdr);
 
 
 /*********************/
@@ -2509,6 +2510,131 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5O_get_hdr_info
+ *
+ * Purpose:	Retrieve the object header information for an object
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *		September 22 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5O_get_hdr_info(const H5O_loc_t *loc, hid_t dxpl_id, H5O_hdr_info_t *hdr)
+{
+    H5O_t *oh = NULL;                   /* Object header */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(H5O_get_hdr_info, FAIL)
+
+    /* Check args */
+    HDassert(loc);
+    HDassert(hdr);
+
+    /* Reset the object header info structure */
+    HDmemset(hdr, 0, sizeof(*hdr));
+
+    /* Get the object header */
+    if(NULL == (oh = H5O_protect(loc, dxpl_id, H5AC_READ)))
+	HGOTO_ERROR(H5E_OHDR, H5E_CANTLOAD, FAIL, "unable to load object header")
+
+    /* Get the information for the object header */
+    if(H5O_get_hdr_info_real(oh, hdr) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't retrieve object header info")
+
+done:
+    if(oh && H5O_unprotect(loc, dxpl_id, 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_hdr_info() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5O_get_hdr_info_real
+ *
+ * Purpose:	Internal routine to retrieve the object header information for an object
+ *
+ * Return:	Success:	Non-negative
+ *		Failure:	Negative
+ *
+ * Programmer:	Quincey Koziol
+ *		September 22 2009
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5O_get_hdr_info_real(const H5O_t *oh, H5O_hdr_info_t *hdr)
+{
+    const H5O_mesg_t *curr_msg;         /* Pointer to current message being operated on */
+    const H5O_chunk_t *curr_chunk;	/* Pointer to current message being operated on */
+    unsigned u;                         /* Local index variable */
+
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5O_get_hdr_info_real)
+
+    /* Check args */
+    HDassert(oh);
+    HDassert(hdr);
+
+    /* Set the version for the object header */
+    hdr->version = oh->version;
+
+    /* Set the number of messages & chunks */
+    hdr->nmesgs = oh->nmesgs;
+    hdr->nchunks = oh->nchunks;
+
+    /* Set the status flags */
+    hdr->flags = oh->flags;
+
+    /* Iterate over all the messages, accumulating message size & type information */
+    hdr->space.meta = H5O_SIZEOF_HDR(oh) + (H5O_SIZEOF_CHKHDR_OH(oh) * (oh->nchunks - 1));
+    hdr->space.mesg = 0;
+    hdr->space.free = 0;
+    hdr->mesg.present = 0;
+    hdr->mesg.shared = 0;
+    for(u = 0, curr_msg = &oh->mesg[0]; u < oh->nmesgs; u++, curr_msg++) {
+        uint64_t type_flag;             /* Flag for message type */
+
+        /* Accumulate space usage information, based on the type of message */
+	if(H5O_NULL_ID == curr_msg->type->id)
+            hdr->space.free += H5O_SIZEOF_MSGHDR_OH(oh) + curr_msg->raw_size;
+        else if(H5O_CONT_ID == curr_msg->type->id)
+            hdr->space.meta += H5O_SIZEOF_MSGHDR_OH(oh) + curr_msg->raw_size;
+        else {
+            hdr->space.meta += H5O_SIZEOF_MSGHDR_OH(oh);
+            hdr->space.mesg += curr_msg->raw_size;
+        } /* end else */
+
+        /* Set flag to indicate presence of message type */
+        type_flag = ((uint64_t)1) << curr_msg->type->id;
+        hdr->mesg.present |= type_flag;
+
+        /* Set flag if the message is shared in some way */
+        if(curr_msg->flags & H5O_MSG_FLAG_SHARED)                                   \
+            hdr->mesg.shared |= type_flag;
+    } /* end for */
+
+    /* Iterate over all the chunks, adding any gaps to the free space */
+    hdr->space.total = 0;
+    for(u = 0, curr_chunk = &oh->chunk[0]; u < oh->nchunks; u++, curr_chunk++) {
+        /* Accumulate the size of the header on disk */
+        hdr->space.total += curr_chunk->size;
+
+        /* If the chunk has a gap, add it to the free space */
+        hdr->space.free += curr_chunk->gap;
+    } /* end for */
+
+    /* Sanity check that all the bytes are accounted for */
+    HDassert(hdr->space.total == (hdr->space.free + hdr->space.meta + hdr->space.mesg));
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5O_get_hdr_info_real() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5O_get_info
  *
  * Purpose:	Retrieve the information for an object
@@ -2594,43 +2720,9 @@ H5O_get_info(const H5O_loc_t *loc, hid_t dxpl_id, hbool_t want_ih_info, H5O_info
         } /* end if */
     } /* end else */
 
-    /* Set the version for the object header */
-    oinfo->hdr.version = oh->version;
-
-    /* Set the number of messages & chunks */
-    oinfo->hdr.nmesgs = oh->nmesgs;
-    oinfo->hdr.nchunks = oh->nchunks;
-
-    /* Set the status flags */
-    oinfo->hdr.flags = oh->flags;
-
-    /* Iterate over all the messages, accumulating message size & type information */
-    oinfo->hdr.space.meta = H5O_SIZEOF_HDR(oh) + (H5O_SIZEOF_CHKHDR_OH(oh) * (oh->nchunks - 1));
-    oinfo->hdr.space.mesg = 0;
-    oinfo->hdr.space.free = 0;
-    oinfo->hdr.mesg.present = 0;
-    oinfo->hdr.mesg.shared = 0;
-    for(u = 0, curr_msg = &oh->mesg[0]; u < oh->nmesgs; u++, curr_msg++) {
-        uint64_t type_flag;             /* Flag for message type */
-
-        /* Accumulate space usage information, based on the type of message */
-	if(H5O_NULL_ID == curr_msg->type->id)
-            oinfo->hdr.space.free += H5O_SIZEOF_MSGHDR_OH(oh) + curr_msg->raw_size;
-        else if(H5O_CONT_ID == curr_msg->type->id)
-            oinfo->hdr.space.meta += H5O_SIZEOF_MSGHDR_OH(oh) + curr_msg->raw_size;
-        else {
-            oinfo->hdr.space.meta += H5O_SIZEOF_MSGHDR_OH(oh);
-            oinfo->hdr.space.mesg += curr_msg->raw_size;
-        } /* end else */
-
-        /* Set flag to indicate presence of message type */
-        type_flag = ((uint64_t)1) << curr_msg->type->id;
-        oinfo->hdr.mesg.present |= type_flag;
-
-        /* Set flag if the message is shared in some way */
-        if(curr_msg->flags & H5O_MSG_FLAG_SHARED)                                   \
-            oinfo->hdr.mesg.shared |= type_flag;
-    } /* end for */
+    /* Get the information for the object header */
+    if(H5O_get_hdr_info_real(oh, &oinfo->hdr) < 0)
+        HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't retrieve object header info")
 
     /* Retrieve # of attributes */
     oinfo->num_attrs = H5O_attr_count_real(loc->file, dxpl_id, oh);
@@ -2641,19 +2733,6 @@ H5O_get_info(const H5O_loc_t *loc, hid_t dxpl_id, hbool_t want_ih_info, H5O_info
             HGOTO_ERROR(H5E_ATTR, H5E_CANTGET, FAIL, "can't retrieve attribute btree & heap info")
     } /* end if */
 
-    /* Iterate over all the chunks, adding any gaps to the free space */
-    oinfo->hdr.space.total = 0;
-    for(u = 0, curr_chunk = &oh->chunk[0]; u < oh->nchunks; u++, curr_chunk++) {
-        /* Accumulate the size of the header on disk */
-        oinfo->hdr.space.total += curr_chunk->size;
-
-        /* If the chunk has a gap, add it to the free space */
-        oinfo->hdr.space.free += curr_chunk->gap;
-    } /* end for */
-
-    /* Sanity check that all the bytes are accounted for */
-    HDassert(oinfo->hdr.space.total == (oinfo->hdr.space.free + oinfo->hdr.space.meta + oinfo->hdr.space.mesg));
-
 done:
     if(oh && H5O_unprotect(loc, dxpl_id, oh, H5AC__NO_FLAGS_SET) < 0)
 	HDONE_ERROR(H5E_OHDR, H5E_CANTUNPROTECT, FAIL, "unable to release object header")
diff --git a/src/H5Oprivate.h b/src/H5Oprivate.h
index e0364c7..551f7b8 100644
--- a/src/H5Oprivate.h
+++ b/src/H5Oprivate.h
@@ -559,6 +559,7 @@ H5_DLL herr_t H5O_touch_oh(H5F_t *f, hid_t dxpl_id, H5O_t *oh,
 H5_DLL herr_t H5O_bogus_oh(H5F_t *f, hid_t dxpl_id, H5O_t *oh, unsigned mesg_flags);
 #endif /* H5O_ENABLE_BOGUS */
 H5_DLL herr_t H5O_delete(H5F_t *f, hid_t dxpl_id, haddr_t addr);
+H5_DLL herr_t H5O_get_hdr_info(const H5O_loc_t *oloc, hid_t dxpl_id, H5O_hdr_info_t *hdr);
 H5_DLL herr_t H5O_get_info(const H5O_loc_t *oloc, hid_t dxpl_id, hbool_t want_ih_info,
     H5O_info_t *oinfo);
 H5_DLL herr_t H5O_obj_type(const H5O_loc_t *loc, H5O_type_t *obj_type, hid_t dxpl_id);
diff --git a/src/H5Opublic.h b/src/H5Opublic.h
index ddf1a93..84fdecc 100644
--- a/src/H5Opublic.h
+++ b/src/H5Opublic.h
@@ -87,6 +87,24 @@ typedef enum H5O_type_t {
     H5O_TYPE_NTYPES             /* Number of different object types (must be last!) */
 } H5O_type_t;
 
+/* Information struct for object header metadata (for H5Oget_info/H5Oget_info_by_name/H5Oget_info_by_idx) */
+typedef struct H5O_hdr_info_t {
+    unsigned version;		/* Version number of header format in file */
+    unsigned nmesgs;		/* Number of object header messages */
+    unsigned nchunks;		/* Number of object header chunks */
+    unsigned flags;             /* Object header status flags */
+    struct {
+        hsize_t total;		/* Total space for storing object header in file */
+        hsize_t meta;		/* Space within header for object header metadata information */
+        hsize_t mesg;		/* Space within header for actual message information */
+        hsize_t free;		/* Free space within object header */
+    } space;
+    struct {
+        uint64_t present;	/* Flags to indicate presence of message type in header */
+        uint64_t shared;	/* Flags to indicate message type is shared in header */
+    } mesg;
+} H5O_hdr_info_t;
+
 /* Information struct for object (for H5Oget_info/H5Oget_info_by_name/H5Oget_info_by_idx) */
 typedef struct H5O_info_t {
     unsigned long 	fileno;		/* File number that object is located in */
@@ -98,22 +116,7 @@ typedef struct H5O_info_t {
     time_t		ctime;		/* Change time			*/
     time_t		btime;		/* Birth time			*/
     hsize_t 		num_attrs;	/* # of attributes attached to object */
-    struct {
-        unsigned version;		/* Version number of header format in file */
-        unsigned nmesgs;		/* Number of object header messages */
-        unsigned nchunks;		/* Number of object header chunks */
-        unsigned flags;                 /* Object header status flags */
-        struct {
-            hsize_t total;		/* Total space for storing object header in file */
-            hsize_t meta;		/* Space within header for object header metadata information */
-            hsize_t mesg;		/* Space within header for actual message information */
-            hsize_t free;		/* Free space within object header */
-        } space;
-        struct {
-            uint64_t present;		/* Flags to indicate presence of message type in header */
-            uint64_t shared;		/* Flags to indicate message type is shared in header */
-        } mesg;
-    } hdr;
+    H5O_hdr_info_t      hdr;            /* Object header information */
     /* Extra metadata storage for obj & attributes */
     struct {
         H5_ih_info_t   obj;             /* v1/v2 B-tree & local/fractal heap for groups, B-tree for chunked datasets */