maint: update copyright

[gnulib.git] / m4 / putenv.m4

diff --git a/m4/putenv.m4 b/m4/putenv.m4
index 0bb17f4..d79321b 100644 (file)
--- a/m4/putenv.m4
+++ b/m4/putenv.m4
@@ -1,10 +1,8 @@
-# putenv.m4 serial 8
-dnl Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
-dnl This file is free software, distributed under the terms of the GNU
-dnl General Public License.  As a special exception to the GNU General
-dnl Public License, this file may be distributed as part of a program
-dnl that contains a configuration script generated by Autoconf, under
-dnl the same distribution terms as the rest of that program.
+# putenv.m4 serial 20
+dnl Copyright (C) 2002-2014 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.
 
 dnl From Jim Meyering.
 dnl
@@ -12,40 +10,47 @@ dnl Check whether putenv ("FOO") removes FOO from the environment.
 dnl The putenv in libc on at least SunOS 4.1.4 does *not* do that.
 
 AC_DEFUN([gl_FUNC_PUTENV],
-[AC_CACHE_CHECK([for SVID conformant putenv], jm_cv_func_svid_putenv,
-  [AC_TRY_RUN([
-    int
-    main ()
-    {
-      /* Put it in env.  */
-      if (putenv ("CONFTEST_putenv=val"))
-        exit (1);
+[
+  AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+  AC_CACHE_CHECK([for putenv compatible with GNU and SVID],
+   [gl_cv_func_svid_putenv],
+   [AC_RUN_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT],[[
+    /* Put it in env.  */
+    if (putenv ("CONFTEST_putenv=val"))
+      return 1;
 
-      /* Try to remove it.  */
-      if (putenv ("CONFTEST_putenv"))
-        exit (1);
+    /* Try to remove it.  */
+    if (putenv ("CONFTEST_putenv"))
+      return 2;
 
-      /* Make sure it was deleted.  */
-      if (getenv ("CONFTEST_putenv") != 0)
-        exit (1);
+    /* Make sure it was deleted.  */
+    if (getenv ("CONFTEST_putenv") != 0)
+      return 3;
 
-      exit (0);
-    }
-             ],
-            jm_cv_func_svid_putenv=yes,
-            jm_cv_func_svid_putenv=no,
-            dnl When crosscompiling, assume putenv is broken.
-            jm_cv_func_svid_putenv=no)
-  ])
-  if test $jm_cv_func_svid_putenv = no; then
-    AC_LIBOBJ(putenv)
-    AC_DEFINE(putenv, rpl_putenv,
-      [Define to rpl_putenv if the replacement function should be used.])
-    gl_PREREQ_PUTENV
-  fi
+    return 0;
+              ]])],
+             gl_cv_func_svid_putenv=yes,
+             gl_cv_func_svid_putenv=no,
+             dnl When crosscompiling, assume putenv is broken.
+             [case "$host_os" in
+                        # Guess yes on glibc systems.
+                *-gnu*) gl_cv_func_svid_putenv="guessing yes" ;;
+                        # If we don't know, assume the worst.
+                *)      gl_cv_func_svid_putenv="guessing no" ;;
+              esac
+             ])
+   ])
+  case "$gl_cv_func_svid_putenv" in
+    *yes) ;;
+    *)
+      REPLACE_PUTENV=1
+      ;;
+  esac
 ])
 
 # Prerequisites of lib/putenv.c.
-AC_DEFUN([gl_PREREQ_PUTENV], [
-  AC_CHECK_HEADERS_ONCE(unistd.h)
+AC_DEFUN([gl_PREREQ_PUTENV],
+[
+  AC_CHECK_DECLS([_putenv])
 ])