[svn-r8781]

Purpose:
HDF5 now supports SZIP with no encoder.

Description:
SZIP can be configured to have both encoder and decoder or just to have the decoder.  HDF5 can now query the configuration of any filter, and will throw errors if users try to write using a filter with encoding disabled.

Solution:
Added H5Zget_filter_info function, changed API for H5Pget_filter and H5P_get_filter_by_id.  See SZIP RFC.

Platforms tested:
Copper (fortran, C++, parallel), Sleipnir (C++), Arabica (fortran, C++), Verbena (fortran, C++)

Misc. update:

1 files changed, 60 insertions, 2 deletions

diff --git a/src/H5Z.c b/src/H5Z.c
index bf3998f..78a80fa 100644
--- a/src/H5Z.c
+++ b/src/H5Z.c
@@ -216,6 +216,13 @@ H5Zregister(const H5Z_class_t *cls)
     /* Check args */
     if (cls==NULL)
 	HGOTO_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL, "invalid filter class")
+
+    /* Check H5Z_class_t version number; this is where a function to convert
+     * from an outdated version should be called.
+     */
+    if(cls->version != H5Z_CLASS_T_VERS)
+    HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "invalid H5Z_class_t version number");
+
     if (cls->id<0 || cls->id>H5Z_FILTER_MAX)
 	HGOTO_ERROR (H5E_ARGS, H5E_BADVALUE, FAIL, "invalid filter identification number")
     if (cls->id<H5Z_FILTER_RESERVED)
@@ -519,6 +526,11 @@ H5Z_prelude_callback(hid_t dcpl_id, hid_t type_id, H5Z_prelude_type_t prelude_ty
                         /* Make correct callback */
                         switch(prelude_type) {
                             case H5Z_PRELUDE_CAN_APPLY:
+                                /* Check if filter is configured to be able to encode */
+                                if(! fclass->encoder_present)
+                                    HGOTO_ERROR(H5E_PLINE, H5E_NOENCODER, FAIL, "Filter present but encoding is disabled.");
+
+
                                 /* Check if there is a "can apply" callback */
                                 if(fclass->can_apply) {
                                     /* Make callback to filter's "can apply" function */
@@ -600,7 +612,7 @@ herr_t
 H5Z_can_apply (hid_t dcpl_id, hid_t type_id)
 {
     herr_t ret_value=SUCCEED;   /* Return value */
-    
+
     FUNC_ENTER_NOAPI(H5Z_can_apply,FAIL)
 
     assert (H5I_GENPROP_LST==H5I_get_type(dcpl_id));
@@ -608,7 +620,7 @@ H5Z_can_apply (hid_t dcpl_id, hid_t type_id)
 
     /* Make "can apply" callbacks for filters in pipeline */
     if(H5Z_prelude_callback(dcpl_id, type_id, H5Z_PRELUDE_CAN_APPLY)<0)
-        HGOTO_ERROR(H5E_PLINE, H5E_CANAPPLY, FAIL, "filter parameters not appropriate")
+        HGOTO_ERROR(H5E_PLINE, H5E_CANAPPLY, FAIL, "unable to apply filter")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
@@ -1157,3 +1169,49 @@ H5Z_delete(H5O_pline_t *pline, H5Z_filter_t filter)
 done:
     FUNC_LEAVE_NOAPI(ret_value)
 } 
+
+/*-------------------------------------------------------------------------
+ * Function: H5Zget_filter_info
+ *
+ * Purpose: Gets information about a pipeline data filter and stores it
+ *          in filter_config_flags.
+ *
+ * Return: zero on success / negative on failure
+ *
+ * Programmer: James Laird and Nat Furrer
+ *              Monday, June 7, 2004
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t H5Zget_filter_info(H5Z_filter_t filter, unsigned int *filter_config_flags)
+{
+    herr_t ret_value=SUCCEED;
+    H5Z_class_t * fclass;
+
+    FUNC_ENTER_API(H5Zget_filter_info, FAIL)
+
+    fclass = H5Z_find(filter);
+
+#ifdef H5_WANT_H5_V1_6_COMPAT
+    if(fclass == NULL && filter_config_flags != NULL)
+        *filter_config_flags = 0;
+#else
+    if(fclass == NULL)
+        HGOTO_ERROR(H5E_ARGS, H5E_BADVALUE, FAIL, "Filter not defined")
+#endif /* H5_WANT_H5_V1_6_COMPAT */
+
+    if(filter_config_flags != NULL)
+    {
+        *filter_config_flags = 0;
+
+        if(fclass->encoder_present)
+            *filter_config_flags |= H5Z_FILTER_CONFIG_ENCODE_ENABLED;
+        if(fclass->decoder_present)
+            *filter_config_flags |= H5Z_FILTER_CONFIG_DECODE_ENABLED;
+    }
+
+done:
+    FUNC_LEAVE_API(ret_value)
+}