* editfns.c (Fbyte_to_string): Signal an error if arg is not a byte.

2 files changed, 7 insertions, 1 deletions

diff --git a/src/ChangeLog b/src/ChangeLog
index 4655ea714ad..f986c03cc14 100644
--- a/src/ChangeLog
+++ b/src/ChangeLog
@@ -1,3 +1,7 @@
+2010-11-21  Chong Yidong  <cyd@stupidchicken.com>
+
+        * editfns.c (Fbyte_to_string): Signal an error arg is not a byte.
+
 2010-11-20  Jan Djärv  <jan.h.d@swipnet.se>
 
         * gtkutil.c (menubar_map_cb): New function (Bug#7425).
diff --git a/src/editfns.c b/src/editfns.c
index ea279a462f2..910fd13aed4 100644
--- a/src/editfns.c
+++ b/src/editfns.c
@@ -222,12 +222,14 @@ usage: (char-to-string CHAR)  */)
 }
 
 DEFUN ("byte-to-string", Fbyte_to_string, Sbyte_to_string, 1, 1, 0,
-       doc: /* Convert arg BYTE to a string containing that byte.  */)
+       doc: /* Convert arg BYTE to a unibyte string containing that byte.  */)
      (byte)
      Lisp_Object byte;
 {
   unsigned char b;
   CHECK_NUMBER (byte);
+  if (XINT (byte) < 0 || XINT (byte) > 255)
+    error ("Invalid byte");
   b = XINT (byte);
   return make_string_from_bytes (&b, 1, 1);
 }