+
+ if (attributes & EFI_VARIABLE_APPEND_WRITE) {
+ if (!prefix(old_val, "(blob)")) {
+ ret = EFI_DEVICE_ERROR;
+ goto out;
+ }
+ old_size = strlen(old_val);
+ } else {
+ old_size = 0;
+ }
+ } else {
+ if (data_size == 0 || !attributes ||
+ (attributes & EFI_VARIABLE_APPEND_WRITE)) {
+ /*
+ * Trying to delete or to update a non-existent
+ * variable.
+ */
+ ret = EFI_NOT_FOUND;
+ goto out;
+ }
+
+ old_size = 0;