X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;ds=sidebyside;f=m4%2Ffchdir.m4;h=30e0af1639e834297463b527ca5ffc1328cb8250;hb=14c0eff67c28b3adafbb9a98424eec4a2714e0bb;hp=bcaf056c788be81eea8ddc441854d00603ff1f49;hpb=4475e25b6a19e31e5783781f2132cdbd05bcf7c4;p=gnulib.git

diff --git a/m4/fchdir.m4 b/m4/fchdir.m4
index bcaf056c7..30e0af163 100644
--- a/m4/fchdir.m4
+++ b/m4/fchdir.m4
@@ -1,5 +1,5 @@
-# fchdir.m4 serial 9
-dnl Copyright (C) 2006-2009 Free Software Foundation, Inc.
+# fchdir.m4 serial 20
+dnl Copyright (C) 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.
@@ -8,22 +8,25 @@ AC_DEFUN([gl_FUNC_FCHDIR],
 [
   AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
   AC_REQUIRE([gl_DIRENT_H_DEFAULTS])
-  AC_CHECK_FUNCS_ONCE([fchdir])
-  if test $ac_cv_func_fchdir = no; then
-    REPLACE_FCHDIR=1
+
+  AC_CHECK_DECLS_ONCE([fchdir])
+  if test $ac_cv_have_decl_fchdir = no; then
+    HAVE_DECL_FCHDIR=0
+  fi
+
+  AC_REQUIRE([gl_TEST_FCHDIR])
+  if test $HAVE_FCHDIR = 0; then
     AC_LIBOBJ([fchdir])
     gl_PREREQ_FCHDIR
-    AC_DEFINE([FCHDIR_REPLACEMENT], [1],
-      [Define if gnulib's fchdir() replacement is used.])
-    gl_REPLACE_OPEN
-    gl_REPLACE_CLOSE
-    gl_REPLACE_DUP2
-    dnl dup3 is already unconditionally replaced
-    gl_REPLACE_DIRENT_H
+    AC_DEFINE([REPLACE_FCHDIR], [1],
+      [Define to 1 if gnulib's fchdir() replacement is used.])
+    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.
     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);])],
+]], [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"])])
@@ -34,5 +37,15 @@ work around the inability to open a directory.])
   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
+])
+
 # Prerequisites of lib/fchdir.c.
 AC_DEFUN([gl_PREREQ_FCHDIR], [:])