[svn-r13067] Description:

    Add [quite] limited ability to update (ie. write) data for objects in
fractal heap.  Limited to just updating objects in managed heap blocks (i.e.
not 'tiny' or 'huge' objects) and must be updated with data of the same length
as the object in the heap.  Updating objects in compressed heaps does work
though [as long as the data isn't 'tiny' or 'huge'].
    Needed for changing the data value or the name of an attribute that is
stored in dense or shared storage.

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

1 files changed, 115 insertions, 6 deletions

diff --git a/src/H5HF.c b/src/H5HF.c
index 425fa85..e53a793 100644
--- a/src/H5HF.c
+++ b/src/H5HF.c
@@ -83,9 +83,9 @@ H5FL_DEFINE_STATIC(H5HF_t);
 
 
 /*-------------------------------------------------------------------------
- * Function:	H5HF_op_memcpy
+ * Function:	H5HF_op_read
  *
- * Purpose:	Performs a 'memcpy' operation for a heap 'op' callback
+ * Purpose:	Performs a 'read' operation for a heap 'op' callback
  *
  * Return:	SUCCEED/FAIL
  *
@@ -96,15 +96,40 @@ H5FL_DEFINE_STATIC(H5HF_t);
  *-------------------------------------------------------------------------
  */
 herr_t
-H5HF_op_memcpy(const void *obj, size_t obj_len, void *op_data)
+H5HF_op_read(const void *obj, size_t obj_len, void *op_data)
 {
-    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_op_memcpy)
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_op_read)
 
-    /* Perform memcpy() */
+    /* Perform "read", using memcpy() */
     HDmemcpy(op_data, obj, obj_len);
 
     FUNC_LEAVE_NOAPI(SUCCEED)
-} /* end H5HF_op_memcpy() */
+} /* end H5HF_op_read() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5HF_op_write
+ *
+ * Purpose:	Performs a 'write' operation for a heap 'op' callback
+ *
+ * Return:	SUCCEED/FAIL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Dec 18 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_op_write(const void *obj, size_t obj_len, void *op_data)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5HF_op_write)
+
+    /* Perform "write", using memcpy() */
+    HDmemcpy((void *)obj, op_data, obj_len);    /* Casting away const OK -QAK */
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5HF_op_write() */
 
 
 /*-------------------------------------------------------------------------
@@ -516,10 +541,94 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function:	H5HF_write
+ *
+ * Purpose:	Write an object from a buffer into a fractal heap
+ *
+ * Notes:	Writing objects in "managed" heap blocks is only storage
+ *		method currently supported.  (Which could be expanded to
+ *		'huge' and 'tiny' objects, with some work)
+ *
+ *		Also, assumes that the 'op' routine modifies the data, and
+ *		marks data to be written back to disk, even if 'op' routine
+ *		didn't actually change anything.  (Which could be modified
+ *		to pass "did_modify" flag to callback, if necessary)
+ *
+ *		Also, assumes that object to write is same size as object in
+ *		heap.
+ *
+ * Return:	SUCCEED/FAIL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@hdfgroup.org
+ *		Dec 18 2006
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5HF_write(H5HF_t *fh, hid_t dxpl_id, void *_id, hbool_t UNUSED *id_changed,
+    const void *obj)
+{
+    uint8_t *id = (uint8_t *)_id;       /* Object ID */
+    uint8_t id_flags;                   /* Heap ID flag bits */
+    herr_t ret_value = SUCCEED;         /* Return value */
+
+    FUNC_ENTER_NOAPI(H5HF_write, FAIL)
+
+    /*
+     * Check arguments.
+     */
+    HDassert(fh);
+    HDassert(id);
+    HDassert(obj);
+
+    /* Get the ID flags */
+    id_flags = *id;
+
+    /* Check for correct heap ID version */
+    if((id_flags & H5HF_ID_VERS_MASK) != H5HF_ID_VERS_CURR)
+        HGOTO_ERROR(H5E_HEAP, H5E_VERSION, FAIL, "incorrect heap ID version")
+
+    /* Set the shared heap header's file context for this operation */
+    fh->hdr->f = fh->f;
+
+    /* Check type of object in heap */
+    if((id_flags & H5HF_ID_TYPE_MASK) == H5HF_ID_TYPE_MAN) {
+        /* Operate on object from managed heap blocks */
+        /* (ID can't change and modifying object is "easy" to manage) */
+        if(H5HF_man_write(fh->hdr, dxpl_id, id, obj) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTOPERATE, FAIL, "can't operate on object from fractal heap")
+    } /* end if */
+    else if((id_flags & H5HF_ID_TYPE_MASK) == H5HF_ID_TYPE_HUGE) {
+        /* Check for writing a 'huge' object */
+        /* (which isn't supported yet - ID could change and lots of work to re-compress changed object) */
+        HGOTO_ERROR(H5E_HEAP, H5E_UNSUPPORTED, FAIL, "modifying 'huge' object not supported yet")
+    } /* end if */
+    else if((id_flags & H5HF_ID_TYPE_MASK) == H5HF_ID_TYPE_TINY) {
+        /* Check for writing a 'tiny' object */
+        /* (which isn't supported yet - ID will change) */
+        HGOTO_ERROR(H5E_HEAP, H5E_UNSUPPORTED, FAIL, "modifying 'tiny' object not supported yet")
+    } /* end if */
+    else {
+HDfprintf(stderr, "%s: Heap ID type not supported yet!\n", FUNC);
+HGOTO_ERROR(H5E_HEAP, H5E_UNSUPPORTED, FAIL, "heap ID type not supported yet")
+    } /* end else */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5HF_write() */
+
+
+/*-------------------------------------------------------------------------
  * Function:	H5HF_op
  *
  * Purpose:	Perform an operation directly on a heap object
  *
+ * Note:	The library routines currently assume that the 'op' callback 
+ *		won't modify the object.  This can easily be changed later for
+ *		"managed" heap objects, and, with some difficulty, for 'huge'
+ *		and 'tiny' heap objects.
+ *
  * Return:	SUCCEED/FAIL
  *
  * Programmer:	Quincey Koziol