Import upstream version 1.26

[debian/tar] / m4 / setenv.m4

diff --git a/m4/setenv.m4 b/m4/setenv.m4
index 7af13d724163c4e5a6ba4071365a929b5a496762..ba619b082e4b9d54878d4f79bb79e2bb3b2419e0 100644 (file)
--- a/m4/setenv.m4
+++ b/m4/setenv.m4
@@ -1,17 +1,14 @@
-# setenv.m4 serial 10
-dnl Copyright (C) 2001-2004, 2006-2008 Free Software Foundation, Inc.
+# setenv.m4 serial 21
+dnl Copyright (C) 2001-2004, 2006-2011 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_REQUIRE([gl_STDLIB_H_DEFAULTS])
-  AC_CHECK_FUNCS_ONCE([setenv])
-  if test $ac_cv_func_setenv = no; then
-    HAVE_SETENV=0
+  AC_REQUIRE([gl_FUNC_SETENV_SEPARATE])
+  if test $HAVE_SETENV$REPLACE_SETENV != 10; then
     AC_LIBOBJ([setenv])
-    gl_PREREQ_SETENV
   fi
 ])
 
@@ -19,9 +16,42 @@ AC_DEFUN([gl_FUNC_SETENV],
 AC_DEFUN([gl_FUNC_SETENV_SEPARATE],
 [
   AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
+  AC_CHECK_DECLS_ONCE([setenv])
+  if test $ac_cv_have_decl_setenv = no; then
+    HAVE_DECL_SETENV=0
+  fi
   AC_CHECK_FUNCS_ONCE([setenv])
   if test $ac_cv_func_setenv = no; then
     HAVE_SETENV=0
+  else
+    AC_CACHE_CHECK([whether setenv validates arguments],
+      [gl_cv_func_setenv_works],
+      [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
+       #include <stdlib.h>
+       #include <errno.h>
+       #include <string.h>
+      ]], [[
+       int result = 0;
+       {
+         if (setenv ("", "", 0) != -1)
+           result |= 1;
+         else if (errno != EINVAL)
+           result |= 2;
+       }
+       {
+         if (setenv ("a", "=", 1) != 0)
+           result |= 4;
+         else if (strcmp (getenv ("a"), "=") != 0)
+           result |= 8;
+       }
+       return result;
+      ]])],
+      [gl_cv_func_setenv_works=yes], [gl_cv_func_setenv_works=no],
+      [gl_cv_func_setenv_works="guessing no"])])
+    if test "$gl_cv_func_setenv_works" != yes; then
+      REPLACE_SETENV=1
+      AC_LIBOBJ([setenv])
+    fi
   fi
   gl_PREREQ_SETENV
 ])
@@ -29,14 +59,23 @@ AC_DEFUN([gl_FUNC_SETENV_SEPARATE],
 AC_DEFUN([gl_FUNC_UNSETENV],
 [
   AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
+  AC_CHECK_DECLS_ONCE([unsetenv])
+  if test $ac_cv_have_decl_unsetenv = no; then
+    HAVE_DECL_UNSETENV=0
+  fi
   AC_CHECK_FUNCS([unsetenv])
   if test $ac_cv_func_unsetenv = no; then
-    HAVE_UNSETENV=0
     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>
+    dnl Some BSDs return void, failing to do error checking.
+    AC_CACHE_CHECK([for unsetenv() return type], [gt_cv_func_unsetenv_ret],
+      [AC_COMPILE_IFELSE(
+         [AC_LANG_PROGRAM(
+            [[
+#undef _BSD
+#define _BSD 1 /* unhide unsetenv declaration in OSF/1 5.1 <stdlib.h> */
+#include <stdlib.h>
 extern
 #ifdef __cplusplus
 "C"
@@ -46,9 +85,48 @@ int unsetenv (const char *name);
 #else
 int unsetenv();
 #endif
-], , gt_cv_func_unsetenv_ret='int', gt_cv_func_unsetenv_ret='void')])
+            ]],
+            [[]])],
+         [gt_cv_func_unsetenv_ret='int'],
+         [gt_cv_func_unsetenv_ret='void'])])
     if test $gt_cv_func_unsetenv_ret = 'void'; then
-      VOID_UNSETENV=1
+      AC_DEFINE([VOID_UNSETENV], [1], [Define to 1 if unsetenv returns void
+       instead of int.])
+      REPLACE_UNSETENV=1
+      AC_LIBOBJ([unsetenv])
+    fi
+
+    dnl Solaris 10 unsetenv does not remove all copies of a name.
+    dnl Haiku alpha 2 unsetenv gets confused by assignment to environ.
+    dnl OpenBSD 4.7 unsetenv("") does not fail.
+    AC_CACHE_CHECK([whether unsetenv obeys POSIX],
+      [gl_cv_func_unsetenv_works],
+      [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
+       #include <stdlib.h>
+       #include <errno.h>
+       extern char **environ;
+      ]], [[
+       char entry1[] = "a=1";
+       char entry2[] = "b=2";
+       char *env[] = { entry1, entry2, NULL };
+       if (putenv ((char *) "a=1")) return 1;
+       if (putenv (entry2)) return 2;
+       entry2[0] = 'a';
+       unsetenv ("a");
+       if (getenv ("a")) return 3;
+       if (!unsetenv ("") || errno != EINVAL) return 4;
+       entry2[0] = 'b';
+       environ = env;
+       if (!getenv ("a")) return 5;
+       entry2[0] = 'a';
+       unsetenv ("a");
+       if (getenv ("a")) return 6;
+      ]])],
+      [gl_cv_func_unsetenv_works=yes], [gl_cv_func_unsetenv_works=no],
+      [gl_cv_func_unsetenv_works="guessing no"])])
+    if test "$gl_cv_func_unsetenv_works" != yes; then
+      REPLACE_UNSETENV=1
+      AC_LIBOBJ([unsetenv])
     fi
   fi
 ])
@@ -58,14 +136,14 @@ AC_DEFUN([gl_PREREQ_SETENV],
 [
   AC_REQUIRE([AC_FUNC_ALLOCA])
   AC_REQUIRE([gl_ENVIRON])
-  AC_CHECK_HEADERS_ONCE(unistd.h)
-  AC_CHECK_HEADERS(search.h)
-  AC_CHECK_FUNCS(tsearch)
+  AC_CHECK_HEADERS_ONCE([unistd.h])
+  AC_CHECK_HEADERS([search.h])
+  AC_CHECK_FUNCS([tsearch])
 ])
 
 # Prerequisites of lib/unsetenv.c.
 AC_DEFUN([gl_PREREQ_UNSETENV],
 [
   AC_REQUIRE([gl_ENVIRON])
-  AC_CHECK_HEADERS_ONCE(unistd.h)
+  AC_CHECK_HEADERS_ONCE([unistd.h])
 ])