[svn-r8053] Purpose:

    Bug fix

Description:
    Correct two problems with variable-length datatypes in datasets:
        - When overwriting an entire dataset, writing the fill value to the
            file would be skipped, causing problems for VL datatypes when
            objects in the file had been unlinked (and thus the space in the
            file was not all zeros)
        - When an application has set a fill-value for a dataset and the
            dataset's datatype contained a VL datatype, the library was filling
            space on disk with the memory form of the VL information, instead
            of the disk form.


Platforms tested:
    FreeBSD 4.9 (sleipnir)
    h5committest

1 files changed, 18 insertions, 13 deletions

diff --git a/src/H5Dio.c b/src/H5Dio.c
index 562ee22..f1d6890 100644
--- a/src/H5Dio.c
+++ b/src/H5Dio.c
@@ -220,14 +220,11 @@ H5D_fill(const void *fill, const H5T_t *fill_type, void *buf, const H5T_t *buf_t
     FUNC_ENTER_NOAPI_NOINIT(H5D_fill)
 
     /* Check args */
+    assert(fill_type);
     assert(buf);
     assert(buf_type);
     assert(space);
 
-    /* Check for "default" fill value */
-    if(fill_type==NULL)
-        fill_type=buf_type;
-
     /* Get the memory and file datatype sizes */
     src_type_size = H5T_get_size(fill_type);
     dst_type_size = H5T_get_size(buf_type);
@@ -245,19 +242,20 @@ H5D_fill(const void *fill, const H5T_t *fill_type, void *buf, const H5T_t *buf_t
         /* Copy the user's data into the buffer for conversion */
         HDmemcpy(tconv_buf,fill,src_type_size);
 
-        /* Convert memory buffer into disk buffer */
         /* Set up type conversion function */
-        if (NULL == (tpath = H5T_path_find(fill_type, buf_type, NULL, NULL, dxpl_id))) {
+        if (NULL == (tpath = H5T_path_find(fill_type, buf_type, NULL, NULL, dxpl_id)))
             HGOTO_ERROR(H5E_DATASET, H5E_UNSUPPORTED, FAIL, "unable to convert between src and dest data types")
-        } else if (!H5T_path_noop(tpath)) {
+
+        /* Convert memory buffer into disk buffer */
+        if (!H5T_path_noop(tpath)) {
             if ((src_id = H5I_register(H5I_DATATYPE, H5T_copy(fill_type, H5T_COPY_ALL)))<0 ||
                     (dst_id = H5I_register(H5I_DATATYPE, H5T_copy(buf_type, H5T_COPY_ALL)))<0)
                 HGOTO_ERROR(H5E_DATASET, H5E_CANTREGISTER, FAIL, "unable to register types for conversion")
-        }
 
-        /* Perform data type conversion */
-        if (H5T_convert(tpath, src_id, dst_id, (hsize_t)1, 0, 0, tconv_buf, bkg_buf, dxpl_id)<0)
-            HGOTO_ERROR(H5E_DATASET, H5E_CANTCONVERT, FAIL, "data type conversion failed")
+            /* Perform data type conversion */
+            if (H5T_convert(tpath, src_id, dst_id, (hsize_t)1, 0, 0, tconv_buf, bkg_buf, dxpl_id)<0)
+                HGOTO_ERROR(H5E_DATASET, H5E_CANTCONVERT, FAIL, "data type conversion failed")
+        } /* end if */
     } /* end if */
 
     /* Fill the selection in the memory buffer */
@@ -600,7 +598,7 @@ H5D_read(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
             HGOTO_DONE(SUCCEED)
 
         /* Go fill the user's selection with the dataset's fill value */
-        if(H5D_fill(fill.buf,fill.type,buf,mem_type,mem_space, dxpl_id)<0)
+        if(H5D_fill(fill.buf,dataset->type,buf,mem_type,mem_space, dxpl_id)<0)
             HGOTO_ERROR(H5E_DATASET, H5E_READERROR, FAIL, "filling buf failed")
         else
             HGOTO_DONE(SUCCEED)
@@ -819,13 +817,20 @@ H5D_write(H5D_t *dataset, const H5T_t *mem_type, const H5S_t *mem_space,
     if(nelmts > 0 && dataset->efl.nused==0 && dataset->layout.type!=H5D_COMPACT 
             && dataset->layout.addr==HADDR_UNDEF) {
         hssize_t file_nelmts;   /* Number of elements in file dataset's dataspace */
+        hbool_t full_overwrite; /* Whether we are over-writing all the elements */
 
         /* Get the number of elements in file dataset's dataspace */
         if((file_nelmts=H5S_get_simple_extent_npoints(file_space))<0)
             HGOTO_ERROR (H5E_DATASET, H5E_BADVALUE, FAIL, "can't retrieve number of elements in file dataset")
 
+        /* Always allow fill values to be written if the dataset has a VL datatype */
+        if(H5T_detect_class(dataset->type, H5T_VLEN))
+            full_overwrite=FALSE;
+        else
+            full_overwrite=(hsize_t)file_nelmts==nelmts ? TRUE : FALSE;
+
  	/* Allocate storage */
-        if(H5D_alloc_storage(dataset->ent.file,dxpl_id,dataset,H5D_ALLOC_WRITE, TRUE, (hbool_t)((hsize_t)file_nelmts==nelmts ? TRUE : FALSE))<0)
+        if(H5D_alloc_storage(dataset->ent.file,dxpl_id,dataset,H5D_ALLOC_WRITE, TRUE, full_overwrite)<0)
             HGOTO_ERROR(H5E_DATASET, H5E_CANTINIT, FAIL, "unable to initialize storage")
     } /* end if */