TIP #643: Provide a public API to retrieve nul terminator length for an encoding

1 files changed, 27 insertions, 0 deletions

diff --git a/generic/tclEncoding.c b/generic/tclEncoding.c
index 52b02fc..efe4b43 100644
--- a/generic/tclEncoding.c
+++ b/generic/tclEncoding.c
@@ -983,6 +983,33 @@ Tcl_GetEncodingNames(
 }
 
 /*
+ *-------------------------------------------------------------------------
+ *
+ * Tcl_GetEncodingNulLength --
+ *
+ *	Given an encoding, return the number of nul bytes used for the
+ *      string termination.
+ *
+ * Results:
+ *	The name of the encoding.
+ *
+ * Side effects:
+ *	None.
+ *
+ *---------------------------------------------------------------------------
+ */
+int
+Tcl_GetEncodingNulLength(
+    Tcl_Encoding encoding)
+{
+    if (encoding == NULL) {
+	encoding = systemEncoding;
+    }
+
+    return ((Encoding *) encoding)->nullSize;
+}
+
+/*
  *------------------------------------------------------------------------
  *
  * Tcl_SetSystemEncoding --