Bugzilla bug 135008: fixed the bug that PL_Base64Decode may step before

the buffer if the source string length is 0.  Thanks to Roger Chickering
<rogc@netscape.com> for the bug fix.


git-svn-id: svn://10.0.0.236/trunk@118019 18797224-902f-48f8-a5cc-f745e15eee43

mozilla/nsprpub/lib/libc/src/base64.c

@@ -383,7 +383,7 @@ PL_Base64Decode
         srclen = PL_strlen(src);
     }
 
-    if( 0 == (srclen & 3) )
+    if( srclen && (0 == (srclen & 3)) )
     {
         if( (char)'=' == src[ srclen-1 ] )
         {