[svn-r27504] Change comments/code around to reflect decision to have virtual datasets always

return TRUE when their is_alloc function is called.

Tested: ummon

4 files changed, 17 insertions, 8 deletions

diff --git a/src/H5Ddbg.c b/src/H5Ddbg.c
index 7e1d884..4e934f2 100644
--- a/src/H5Ddbg.c
+++ b/src/H5Ddbg.c
@@ -116,8 +116,6 @@ H5Ddebug(hid_t dset_id)
 	(void)H5D__chunk_dump_index(dset, H5AC_ind_dxpl_id, stdout);
     else if(H5D_CONTIGUOUS == dset->shared->layout.type)
 	HDfprintf(stdout, "    %-10s %a\n", "Address:", dset->shared->layout.storage.u.contig.addr);
-    else if(H5D_VIRTUAL == dset->shared->layout.type)
-        HDassert(0 && "Not yet implemented...");//VDSINC
 
 done:
     FUNC_LEAVE_API(ret_value)
diff --git a/src/H5Dint.c b/src/H5Dint.c
index 657f893..dd37beb 100644
--- a/src/H5Dint.c
+++ b/src/H5Dint.c
@@ -1827,7 +1827,12 @@ H5D__alloc_storage(const H5D_t *dset, hid_t dxpl_id, H5D_time_alloc_t time_alloc
                 break;
 
             case H5D_VIRTUAL:
-                /* No-op for now VDSINC */
+                /* No-op, as the raw data is stored elsewhere and the global
+                 * heap object containing the mapping information is created
+                 * when the layout message is encoded.  We may wish to move the
+                 * creation of the global heap object here at some point, but we
+                 * will have to make sure is it always created before the
+                 * dataset is closed. */
                 break;
 
             case H5D_LAYOUT_ERROR:
@@ -1950,7 +1955,7 @@ H5D__init_storage(const H5D_t *dset, hbool_t full_overwrite, hsize_t old_dim[],
             } /* end block */
 
         case H5D_VIRTUAL:
-            /* No-op for now VDSINC */
+            /* No-op, as the raw data is stored elsewhere */
 
         case H5D_LAYOUT_ERROR:
         case H5D_NLAYOUTS:
@@ -2009,7 +2014,8 @@ H5D__get_storage_size(H5D_t *dset, hid_t dxpl_id, hsize_t *storage_size)
             break;
 
         case H5D_VIRTUAL:
-            /* Just set to 0 until private data is implemented VDSINC */
+            /* Just set to 0, as virtual datasets do not actually store raw data
+             */
             *storage_size = 0;
             break;
 
diff --git a/src/H5Doh.c b/src/H5Doh.c
index 39a270f..388f4cf 100644
--- a/src/H5Doh.c
+++ b/src/H5Doh.c
@@ -398,7 +398,8 @@ H5O__dset_bh_info(H5F_t *f, hid_t dxpl_id, H5O_t *oh, H5_ih_info_t *bh_info)
         if(H5D__chunk_bh_info(f, dxpl_id, &layout, &pline, &(bh_info->index_size)) < 0)
             HGOTO_ERROR(H5E_OHDR, H5E_CANTGET, FAIL, "can't determine chunked dataset btree info")
     } /* end if */
-    else if(layout.type == H5D_VIRTUAL && H5D__virtual_is_space_alloc(&layout.storage)) {
+    else if(layout.type == H5D_VIRTUAL
+            && (layout.storage.u.virt.serial_list_hobjid.addr != HADDR_UNDEF)) {
         size_t virtual_heap_size;
         /* Need to write a test for this.  No assert here for now because the
          * code is reached by h5_verify_cached_stabs() but it is not properly
diff --git a/src/H5Dvirtual.c b/src/H5Dvirtual.c
index 0b88ad5..99c090f 100644
--- a/src/H5Dvirtual.c
+++ b/src/H5Dvirtual.c
@@ -1933,8 +1933,12 @@ H5D__virtual_is_space_alloc(const H5O_storage_t H5_ATTR_UNUSED *storage)
 
     FUNC_ENTER_PACKAGE_NOERR
 
-    /* Need to decide what to do here.  For now just return TRUE VDSINC */
-    ret_value = TRUE;//storage->u.virt.serial_list_hobjid.addr != HADDR_UNDEF;
+    /* Just return TRUE, since the global heap object containing the mappings is
+     * created when the layout message is encoded, and nothing else needs to be
+     * allocated for virtual datasets.  This also ensures that the library never
+     * assumes (falsely) that no data is present in the dataset, causing errors.
+     */
+    ret_value = TRUE;
 
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5D__virtual_is_space_alloc() */