X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fstrndup.m4;h=f8ea8f2ca774ed249dc9cc7489eeb656f8bce35b;hb=a8ec28b6975fc065b84c511b8108dc3658d2ccd4;hp=66cedb4334c1af2cf0292db9f5738129343254cf;hpb=4a31fee0519738513fdc037c8022384db8c1239d;p=gnulib.git

diff --git a/m4/strndup.m4 b/m4/strndup.m4
index 66cedb433..f8ea8f2ca 100644
--- a/m4/strndup.m4
+++ b/m4/strndup.m4
@@ -1,21 +1,49 @@
-# strndup.m4 serial 5
-dnl Copyright (C) 2002, 2003, 2005 Free Software Foundation, Inc.
+# strndup.m4 serial 17
+dnl Copyright (C) 2002-2003, 2005-2009 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
 
 AC_DEFUN([gl_FUNC_STRNDUP],
 [
-  AC_LIBSOURCES([strndup.c, strndup.h])
-
   dnl Persuade glibc <string.h> to declare strndup().
-  AC_REQUIRE([AC_GNU_SOURCE])
+  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
 
-  AC_REPLACE_FUNCS(strndup)
-  if test $ac_cv_func_strndup = no; then
-    gl_PREREQ_STRNDUP
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+  AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS])
+  AC_CHECK_DECLS_ONCE([strndup])
+  AC_CHECK_FUNCS_ONCE([strndup])
+  if test $ac_cv_have_decl_strndup = no; then
+    HAVE_DECL_STRNDUP=0
   fi
-])
 
-# Prerequisites of lib/strndup.c.
-AC_DEFUN([gl_PREREQ_STRNDUP], [:])
+  if test $ac_cv_func_strndup = yes; then
+    # AIX 4.3.3, AIX 5.1 have a function that fails to add the terminating '\0'.
+    AC_CACHE_CHECK([for working strndup], [gl_cv_func_strndup_works],
+      [AC_RUN_IFELSE([
+         AC_LANG_PROGRAM([[#include <string.h>
+                           #include <stdlib.h>]], [[
+#ifndef HAVE_DECL_STRNDUP
+  extern char *strndup (const char *, size_t);
+#endif
+  char *s;
+  s = strndup ("some longer string", 15);
+  free (s);
+  s = strndup ("shorter string", 13);
+  return s[13] != '\0';]])],
+         [gl_cv_func_strndup_works=yes],
+         [gl_cv_func_strndup_works=no],
+         [case $host_os in
+            aix*) gl_cv_func_strndup_works="guessing no";;
+            *) gl_cv_func_strndup_works="guessing yes";;
+          esac])])
+    case $gl_cv_func_strndup_works in
+      *no)
+        REPLACE_STRNDUP=1
+        AC_LIBOBJ([strndup])
+        ;;
+    esac
+  else
+    AC_LIBOBJ([strndup])
+  fi
+])