1 files changed, 29 insertions, 0 deletions
diff --git a/ext/Data/Util/Util.xs b/ext/Data/Util/Util.xs
new file mode 100644
index 0000000000..6d246ddf51
--- /dev/null
+++ b/ext/Data/Util/Util.xs
@@ -0,0 +1,29 @@
+#include "EXTERN.h"
+#include "perl.h"
+#include "XSUB.h"
+
+
+MODULE=Data::Util   PACKAGE=Data::Util
+
+int
+sv_readonly_flag(...)
+PROTOTYPE: \[$%@];$
+CODE:
+{
+    SV *sv = SvRV(ST(0));
+    IV old = SvREADONLY(sv);
+
+    if (items == 2) {
+        if (SvTRUE(ST(1))) {
+            SvREADONLY_on(sv);
+        }
+        else {
+            SvREADONLY_off(sv);
+        }
+    }
+    if (old)
+        XSRETURN_YES;
+    else
+        XSRETURN_NO;
+}
+