--- a/lib/ChangeLog
+++ b/lib/ChangeLog
@@ -1,3 +1,14 @@
+2006-09-27  Jim Meyering  <jim@meyering.net>
+
+	This function could end up with a definition for a function
+	named __strndup, rather than rpl_strndup on a system with
+	incomplete weak_alias support.
+	* strndup.c (strndup): Rename from __strndup.
+	Remove #defines that used to map __strndup to strndup.
+	Don't use K&R prototypes.
+	Remove LIBC-related code, since this file is not sync'd with glibc.
+	* strndup.h: Revamp, accordingly.
+
 2006-09-27  Paul Eggert  <eggert@cs.ucla.edu>
 
 	* canon-host.c (canon_host_r): Work around bug in Darwin 7.9.0

--- a/lib/strndup.c
+++ b/lib/strndup.c
@@ -1,8 +1,7 @@
-/* Copyright (C) 1996, 1997, 1998, 2001, 2002, 2003, 2005, 2006 Free
-   Software Foundation, Inc.
+/* A replacement function, for systems that lack strndup.
 
-   NOTE: The canonical source of this file is maintained with the GNU C Library.
-   Bugs can be reported to bug-glibc@prep.ai.mit.edu.
+   Copyright (C) 1996, 1997, 1998, 2001, 2002, 2003, 2005, 2006 Free
+   Software Foundation, Inc.
 
    This program is free software; you can redistribute it and/or modify it
    under the terms of the GNU General Public License as published by the
@@ -18,36 +17,18 @@
    along with this program; if not, write to the Free Software Foundation,
    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
 
-#if !_LIBC
-# include <config.h>
-# include "strndup.h"
-#endif
+#include <config.h>
+#include "strndup.h"
 
 #include <stdlib.h>
 #include <string.h>
 
-#if !_LIBC
-# include "strnlen.h"
-# ifndef __strnlen
-#  define __strnlen strnlen
-# endif
-#endif
-
-#undef __strndup
-#if _LIBC
-# undef strndup
-#endif
-
-#ifndef weak_alias
-# define __strndup strndup
-#endif
+#include "strnlen.h"
 
 char *
-__strndup (s, n)
-     const char *s;
-     size_t n;
+strndup (char const *s, size_t n)
 {
-  size_t len = __strnlen (s, n);
+  size_t len = strnlen (s, n);
   char *new = malloc (len + 1);
 
   if (new == NULL)
@@ -56,9 +37,3 @@
   new[len] = '\0';
   return memcpy (new, s, len);
 }
-#ifdef libc_hidden_def
-libc_hidden_def (__strndup)
-#endif
-#ifdef weak_alias
-weak_alias (__strndup, strndup)
-#endif

--- a/lib/strndup.h
+++ b/lib/strndup.h
@@ -1,5 +1,5 @@
 /* Duplicate a size-bounded string.
-   Copyright (C) 2003 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2006 Free Software Foundation, Inc.
 
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -15,16 +15,17 @@
    along with this program; if not, write to the Free Software Foundation,
    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
 
-#if HAVE_STRNDUP
-
-/* Get strndup() declaration.  */
 #include <string.h>
-
-#else
-
 #include <stddef.h>
 
+#ifdef __STRNDUP_PREFIX
+# define _GL_CONCAT(x, y) x ## y
+# define _GL_XCONCAT(x, y) _GL_CONCAT (x, y)
+# define __STRNDUP_ID(y) _GL_XCONCAT (__STRNDUP_PREFIX, y)
+# undef strndup
+# define strndup __STRNDUP_ID (strndup)
+# if !HAVE_DECL_STRNDUP
 /* Return a newly allocated copy of at most N bytes of STRING.  */
 extern char *strndup (const char *string, size_t n);
-
+# endif
 #endif

--- a/m4/ChangeLog
+++ b/m4/ChangeLog
@@ -1,3 +1,7 @@
+2006-09-27  Jim Meyering  <jim@meyering.net>
+
+	* strndup.m4: Modernize.
+
 2006-09-27  Paul Eggert  <eggert@cs.ucla.edu>
 
 	* fpending.m4 (gl_FUNC_FPENDING): Check for stdio_ext at most once.

--- a/m4/strndup.m4
+++ b/m4/strndup.m4
@@ -1,4 +1,4 @@
-# strndup.m4 serial 9
+# strndup.m4 serial 10
 dnl Copyright (C) 2002-2003, 2005-2006 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -39,9 +39,9 @@
     AC_DEFINE([HAVE_STRNDUP], 1,
       [Define if you have the strndup() function and it works.])
   else
+    AC_DEFINE([__STRNDUP_PREFIX], [[rpl_]],
+      [Define to rpl_ if the strndup replacement function should be used.])
     AC_LIBOBJ([strndup])
-    AC_DEFINE(strndup, rpl_strndup,
-      [Define to rpl_strndup if the replacement function should be used,])
     gl_PREREQ_STRNDUP
   fi
 ])