X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fstrchrnul.m4;h=d3dfb9afa25f156ad815617958d636555600fe27;hb=5f70dcfc4f65198adbce63a01a17f18b1627beee;hp=e778d51c7fbf75a78e88172cc350f53a3eee8943;hpb=1e4ece4ab9850fbfa88c9ec43ea518c7bc266792;p=gnulib.git

diff --git a/m4/strchrnul.m4 b/m4/strchrnul.m4
index e778d51c7..d3dfb9afa 100644
--- a/m4/strchrnul.m4
+++ b/m4/strchrnul.m4
@@ -1,5 +1,5 @@
-# strchrnul.m4 serial 4
-dnl Copyright (C) 2003, 2007 Free Software Foundation, Inc.
+# strchrnul.m4 serial 9
+dnl Copyright (C) 2003, 2007, 2009-2012 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.
@@ -7,12 +7,42 @@ dnl with or without modifications, as long as this notice is preserved.
 AC_DEFUN([gl_FUNC_STRCHRNUL],
 [
   dnl Persuade glibc <string.h> to declare strchrnul().
-  AC_REQUIRE([AC_GNU_SOURCE])
+  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
 
-  AC_REPLACE_FUNCS(strchrnul)
+  AC_REQUIRE([gl_HEADER_STRING_H_DEFAULTS])
+  AC_CHECK_FUNCS([strchrnul])
   if test $ac_cv_func_strchrnul = no; then
     HAVE_STRCHRNUL=0
-    gl_PREREQ_STRCHRNUL
+  else
+    AC_CACHE_CHECK([whether strchrnul works],
+      [gl_cv_func_strchrnul_works],
+      [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
+#include <string.h> /* for strchrnul */
+]], [[const char *buf = "a";
+      return strchrnul (buf, 'b') != buf + 1;
+    ]])],
+        [gl_cv_func_strchrnul_works=yes],
+        [gl_cv_func_strchrnul_works=no],
+        [dnl Cygwin 1.7.9 introduced strchrnul, but it was broken until 1.7.10
+         AC_EGREP_CPP([Lucky user],
+           [
+#if defined __CYGWIN__
+ #include <cygwin/version.h>
+ #if CYGWIN_VERSION_DLL_COMBINED > CYGWIN_VERSION_DLL_MAKE_COMBINED (1007, 9)
+  Lucky user
+ #endif
+#else
+  Lucky user
+#endif
+           ],
+           [gl_cv_func_strchrnul_works="guessing yes"],
+           [gl_cv_func_strchrnul_works="guessing no"])
+        ])
+      ])
+    case "$gl_cv_func_strchrnul_works" in
+      *yes) ;;
+      *) REPLACE_STRCHRNUL=1 ;;
+    esac
   fi
 ])