Fixed HDFFV-10933

Description:
    Updated the original fix by Kent Y. in commit
        200a77d8c3e51663c375aafffff607ae9b438f4e
    - used internal functions instead of public API
    - moved some code into the subroutine for a cleaner look.
    - added test to dsets.c
Platforms tested:
    Linux/64 (jelly)

1 files changed, 67 insertions, 0 deletions

diff --git a/src/H5Z.c b/src/H5Z.c
index 616db1f..66acfff 100644
--- a/src/H5Z.c
+++ b/src/H5Z.c
@@ -1004,6 +1004,73 @@ done:
 
 
 /*-------------------------------------------------------------------------
+ * Function: H5Z_ignore_filters
+ *
+ * Purpose:  Determine whether filters can be ignored.
+ *
+ * Description:
+ *      When the filters are optional (i.e., H5Z_FLAG_OPTIONAL is provided,)
+ *      if any of the following conditions is met, the filters will be ignored:
+ *          - dataspace is either H5S_NULL or H5S_SCALAR
+ *          - datatype is variable-length (string or non-string)
+ *      However, if any of these conditions exists and a filter is not
+ *      optional, the function will produce an error.
+ *
+ * Return:   Non-negative(TRUE/FALSE) on success
+ *           Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+htri_t
+H5Z_ignore_filters(hid_t dcpl_id, const H5T_t *type, const H5S_t *space)
+{
+    H5P_genplist_t  *dc_plist;   /* Dataset creation property list object */
+    H5O_pline_t     pline;       /* Object's I/O pipeline information */
+    H5S_class_t     space_class;            /* To check class of space */
+    H5T_class_t     type_class;             /* To check if type is VL */
+    bool            bad_for_filters = FALSE;/* Suitable to have filters */
+    htri_t          ret_value = FALSE;      /* TRUE for ignoring filters */
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    if (NULL == (dc_plist = (H5P_genplist_t *)H5I_object(dcpl_id)))
+        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "can't get dataset creation property list")
+
+    /* Get pipeline information */
+    if (H5P_peek(dc_plist, H5O_CRT_PIPELINE_NAME, &pline) < 0)
+        HGOTO_ERROR(H5E_PLINE, H5E_CANTGET, FAIL, "can't retrieve pipeline filter")
+
+    /* Get datatype and dataspace classes for quick access */
+    space_class = H5S_GET_EXTENT_TYPE(space);
+    type_class = H5T_get_class(type, FALSE);
+
+    /* These conditions are not suitable for filters */
+    bad_for_filters = (H5S_NULL == space_class || H5S_SCALAR == space_class
+        || H5T_VLEN == type_class
+        || (H5T_STRING == type_class && TRUE == H5T_is_variable_str(type)));
+
+    /* When these conditions occur, if there are required filters in pline,
+       then report a failure, otherwise, set flag that they can be ignored */
+    if (bad_for_filters) {
+        size_t ii;
+        if (pline.nused > 0) {
+            for (ii = 0; ii < pline.nused; ii++)
+            {
+                if (!(pline.filter[ii].flags & H5Z_FLAG_OPTIONAL))
+                    HGOTO_ERROR(H5E_PLINE, H5E_CANTFILTER, FAIL, "not suitable for filters")
+            }
+
+            /* All filters are optional, we can ignore them */
+            ret_value = TRUE;
+        }
+    } /* bad for filters */
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5Z_ignore_filters() */
+
+
+/*-------------------------------------------------------------------------
  * Function: H5Z_modify
  *
  * Purpose:  Modify filter parameters for specified pipeline.