New module 'frexpl'.

[gnulib.git] / m4 / setenv.m4

diff --git a/m4/setenv.m4 b/m4/setenv.m4
index 832193b..d6901de 100644 (file)
--- a/m4/setenv.m4
+++ b/m4/setenv.m4
@@ -1,16 +1,55 @@
-# setenv.m4 serial 2 (gettext-0.11.1)
-dnl Copyright (C) 2001-2002 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.
+# setenv.m4 serial 8
+dnl Copyright (C) 2001-2004, 2006-2007 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_SETENV],
+[
+  AC_CHECK_FUNCS_ONCE([setenv])
+  if test $ac_cv_func_setenv = no; then
+    AC_LIBOBJ([setenv])
+    gl_PREREQ_SETENV
+  fi
+])
+
+# Like gl_FUNC_SETENV, except prepare for separate compilation (no AC_LIBOBJ).
+AC_DEFUN([gl_FUNC_SETENV_SEPARATE],
+[
+  AC_CHECK_FUNCS_ONCE([setenv])
+  gl_PREREQ_SETENV
+])
+
+AC_DEFUN([gl_FUNC_UNSETENV],
+[
+  AC_CHECK_FUNCS([unsetenv])
+  if test $ac_cv_func_unsetenv = no; then
+    AC_LIBOBJ([unsetenv])
+    gl_PREREQ_UNSETENV
+  else
+    AC_CACHE_CHECK([for unsetenv() return type], gt_cv_func_unsetenv_ret,
+      [AC_TRY_COMPILE([#include <stdlib.h>
+extern
+#ifdef __cplusplus
+"C"
+#endif
+#if defined(__STDC__) || defined(__cplusplus)
+int unsetenv (const char *name);
+#else
+int unsetenv();
+#endif
+], , gt_cv_func_unsetenv_ret='int', gt_cv_func_unsetenv_ret='void')])
+    if test $gt_cv_func_unsetenv_ret = 'void'; then
+      AC_DEFINE(VOID_UNSETENV, 1, [Define if unsetenv() returns void, not int.])
+    fi
+  fi
+])
 
 # Check if a variable is properly declared.
 # gt_CHECK_VAR_DECL(includes,variable)
 AC_DEFUN([gt_CHECK_VAR_DECL],
 [
-  define(gt_cv_var, [gt_cv_var_]$2[_declaration])
+  define([gt_cv_var], [gt_cv_var_]$2[_declaration])
   AC_MSG_CHECKING([if $2 is properly declared])
   AC_CACHE_VAL(gt_cv_var, [
     AC_TRY_COMPILE([$1
@@ -25,13 +64,19 @@ AC_DEFUN([gt_CHECK_VAR_DECL],
   fi
 ])
 
-# Prerequisites of lib/setenv.c
-
-AC_DEFUN([gt_FUNC_SETENV],
+# Prerequisites of lib/setenv.c.
+AC_DEFUN([gl_PREREQ_SETENV],
 [
-  AC_REPLACE_FUNCS(setenv unsetenv)
-  AC_CHECK_HEADERS(search.h stdlib.h string.h unistd.h)
+  AC_REQUIRE([AC_FUNC_ALLOCA])
+  AC_CHECK_HEADERS_ONCE(unistd.h)
+  AC_CHECK_HEADERS(search.h)
   AC_CHECK_FUNCS(tsearch)
-  gt_CHECK_VAR_DECL([#include <errno.h>], errno)
+  gt_CHECK_VAR_DECL([#include <unistd.h>], environ)
+])
+
+# Prerequisites of lib/unsetenv.c.
+AC_DEFUN([gl_PREREQ_UNSETENV],
+[
+  AC_CHECK_HEADERS_ONCE(unistd.h)
   gt_CHECK_VAR_DECL([#include <unistd.h>], environ)
 ])