-// ----------------------------------------------------------------------------
-// $Id$
-// ----------------------------------------------------------------------------
-// Public Domain C Library - http://pdclib.sourceforge.net
-// This code is Public Domain. Use, modify, and redistribute at will.
-// ----------------------------------------------------------------------------
-
-size_t strcspn( const char * s1, const char * s2 ) { /* TODO */ };
+/* $Id$ */
+
+/* Release $Name$ */
+
+/* strcspn( const char *, const char * )
+
+ This file is part of the Public Domain C Library (PDCLib).
+ Permission is granted to use, modify, and / or redistribute at will.
+*/
+
+#include <string.h>
+
+size_t strcspn( const char * src_1, const char * src_2 )
+{
+ size_t len = 0;
+ const char * src_p;
+ while ( src_1[len] != '\0' )
+ {
+ src_p = src_2;
+ while ( *src_p != '\0' )
+ {
+ if ( src_1[len] == *src_p++ )
+ {
+ return len;
+ }
+ }
+ ++len;
+ }
+ return len;
+}