Import upstream version 1.27

[debian/tar] / m4 / fchdir.m4

diff --git a/m4/fchdir.m4 b/m4/fchdir.m4
index 49d89d1840587ff642ff88764a37358d22d81047..c248fdce58f75af70d65e32086fd8db531ac7ad7 100644 (file)
--- a/m4/fchdir.m4
+++ b/m4/fchdir.m4
@@ -1,5 +1,5 @@
-# fchdir.m4 serial 15
-dnl Copyright (C) 2006-2011 Free Software Foundation, Inc.
+# fchdir.m4 serial 21
+dnl Copyright (C) 2006-2013 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.
@@ -8,16 +8,15 @@ AC_DEFUN([gl_FUNC_FCHDIR],
 [
   AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
   AC_REQUIRE([gl_DIRENT_H_DEFAULTS])
-  AC_REQUIRE([gl_SYS_STAT_H_DEFAULTS])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
 
   AC_CHECK_DECLS_ONCE([fchdir])
   if test $ac_cv_have_decl_fchdir = no; then
     HAVE_DECL_FCHDIR=0
   fi
 
-  AC_CHECK_FUNCS_ONCE([fchdir])
-  if test $ac_cv_func_fchdir = no; then
-    HAVE_FCHDIR=0
+  AC_REQUIRE([gl_TEST_FCHDIR])
+  if test $HAVE_FCHDIR = 0; then
     AC_LIBOBJ([fchdir])
     gl_PREREQ_FCHDIR
     AC_DEFINE([REPLACE_FCHDIR], [1],
@@ -25,27 +24,36 @@ AC_DEFUN([gl_FUNC_FCHDIR],
     dnl We must also replace anything that can manipulate a directory fd,
     dnl to keep our bookkeeping up-to-date.  We don't have to replace
     dnl fstatat, since no platform has fstatat but lacks fchdir.
-    REPLACE_OPENDIR=1
-    REPLACE_CLOSEDIR=1
-    REPLACE_DUP=1
-    gl_REPLACE_OPEN
-    gl_REPLACE_CLOSE
-    gl_REPLACE_DUP2
-    dnl dup3 is already unconditionally replaced
-    gl_REPLACE_FCNTL
-    gl_REPLACE_DIRENT_H
     AC_CACHE_CHECK([whether open can visit directories],
       [gl_cv_func_open_directory_works],
       [AC_RUN_IFELSE([AC_LANG_PROGRAM([[#include <fcntl.h>
 ]], [return open(".", O_RDONLY) < 0;])],
         [gl_cv_func_open_directory_works=yes],
         [gl_cv_func_open_directory_works=no],
-        [gl_cv_func_open_directory_works="guessing no"])])
-    if test "$gl_cv_func_open_directory_works" != yes; then
-      AC_DEFINE([REPLACE_OPEN_DIRECTORY], [1], [Define to 1 if open() should
+        [case "$host_os" in
+                   # Guess yes on glibc systems.
+           *-gnu*) gl_cv_func_open_directory_works="guessing yes" ;;
+                   # If we don't know, assume the worst.
+           *)      gl_cv_func_open_directory_works="guessing no" ;;
+         esac
+        ])])
+    case "$gl_cv_func_open_directory_works" in
+      *yes) ;;
+      *)
+        AC_DEFINE([REPLACE_OPEN_DIRECTORY], [1], [Define to 1 if open() should
 work around the inability to open a directory.])
-      REPLACE_FSTAT=1
-    fi
+        ;;
+    esac
+  fi
+])
+
+# Determine whether to use the overrides in lib/fchdir.c.
+AC_DEFUN([gl_TEST_FCHDIR],
+[
+  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+  AC_CHECK_FUNCS_ONCE([fchdir])
+  if test $ac_cv_func_fchdir = no; then
+    HAVE_FCHDIR=0
   fi
 ])