Import upstream version 1.28

[debian/tar] / m4 / setenv.m4

diff --git a/m4/setenv.m4 b/m4/setenv.m4
index de7171ee5226dc8d2557bc487a863926f3f2c99f..0f46a7bec02900a36437acd1a2197d26f0d4c164 100644 (file)
--- a/m4/setenv.m4
+++ b/m4/setenv.m4
@@ -1,5 +1,5 @@
-# setenv.m4 serial 18
-dnl Copyright (C) 2001-2004, 2006-2010 Free Software Foundation, Inc.
+# setenv.m4 serial 26
+dnl Copyright (C) 2001-2004, 2006-2014 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.
@@ -7,16 +7,7 @@ dnl with or without modifications, as long as this notice is preserved.
 AC_DEFUN([gl_FUNC_SETENV],
 [
   AC_REQUIRE([gl_FUNC_SETENV_SEPARATE])
-  if test $HAVE_SETENV$REPLACE_SETENV != 10; then
-    AC_LIBOBJ([setenv])
-  fi
-])
-
-# Like gl_FUNC_SETENV, except prepare for separate compilation (no AC_LIBOBJ).
-AC_DEFUN([gl_FUNC_SETENV_SEPARATE],
-[
-  AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
-  AC_CHECK_FUNCS_ONCE([setenv])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
   if test $ac_cv_func_setenv = no; then
     HAVE_SETENV=0
   else
@@ -27,45 +18,77 @@ AC_DEFUN([gl_FUNC_SETENV_SEPARATE],
        #include <errno.h>
        #include <string.h>
       ]], [[
-       if (setenv ("", "", 0) != -1) return 1;
-       if (errno != EINVAL) return 2;
-       if (setenv ("a", "=", 1) != 0) return 3;
-       if (strcmp (getenv ("a"), "=") != 0) return 4;
+       int result = 0;
+       {
+         if (setenv ("", "", 0) != -1)
+           result |= 1;
+         else if (errno != EINVAL)
+           result |= 2;
+       }
+       {
+         if (setenv ("a", "=", 1) != 0)
+           result |= 4;
+         else if (strcmp (getenv ("a"), "=") != 0)
+           result |= 8;
+       }
+       return result;
       ]])],
       [gl_cv_func_setenv_works=yes], [gl_cv_func_setenv_works=no],
-      [gl_cv_func_setenv_works="guessing no"])])
-    if test "$gl_cv_func_setenv_works" != yes; then
-      REPLACE_SETENV=1
-      AC_LIBOBJ([setenv])
-    fi
+      [case "$host_os" in
+                 # Guess yes on glibc systems.
+         *-gnu*) gl_cv_func_setenv_works="guessing yes" ;;
+                 # If we don't know, assume the worst.
+         *)      gl_cv_func_setenv_works="guessing no" ;;
+       esac
+      ])])
+    case "$gl_cv_func_setenv_works" in
+      *yes) ;;
+      *)
+        REPLACE_SETENV=1
+        ;;
+    esac
+  fi
+])
+
+# Like gl_FUNC_SETENV, except prepare for separate compilation
+# (no REPLACE_SETENV, no AC_LIBOBJ).
+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])
   gl_PREREQ_SETENV
 ])
 
 AC_DEFUN([gl_FUNC_UNSETENV],
 [
   AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+  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
+    HAVE_UNSETENV=1
     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"
 #endif
-#if defined(__STDC__) || defined(__cplusplus)
 int unsetenv (const char *name);
-#else
-int unsetenv();
-#endif
             ]],
             [[]])],
          [gt_cv_func_unsetenv_ret='int'],
@@ -74,31 +97,48 @@ int unsetenv();
       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 entry[] = "b=2";
+       char entry1[] = "a=1";
+       char entry2[] = "b=2";
+       char *env[] = { entry1, entry2, NULL };
        if (putenv ((char *) "a=1")) return 1;
-       if (putenv (entry)) return 2;
-       entry[0] = 'a';
+       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 "$gl_cv_func_unsetenv_works" != yes; then
-      REPLACE_UNSETENV=1
-      AC_LIBOBJ([unsetenv])
-    fi
+      [case "$host_os" in
+                 # Guess yes on glibc systems.
+         *-gnu*) gl_cv_func_unsetenv_works="guessing yes" ;;
+                 # If we don't know, assume the worst.
+         *)      gl_cv_func_unsetenv_works="guessing no" ;;
+       esac
+      ])])
+    case "$gl_cv_func_unsetenv_works" in
+      *yes) ;;
+      *)
+        REPLACE_UNSETENV=1
+        ;;
+    esac
   fi
 ])