-# fchdir.m4 serial 1
-dnl Copyright (C) 2006 Free Software Foundation, Inc.
+# fchdir.m4 serial 20
+dnl Copyright (C) 2006-2012 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_FCHDIR],
[
- AC_CHECK_FUNCS_ONCE([fchdir])
- if test $ac_cv_func_fchdir = no; then
+ AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+ AC_REQUIRE([gl_DIRENT_H_DEFAULTS])
+
+ 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 $HAVE_FCHDIR = 0; then
AC_LIBOBJ([fchdir])
gl_PREREQ_FCHDIR
- AC_DEFINE([FCHDIR_REPLACEMENT], 1,
- [Define if gnulib's fchdir() replacement is used.])
- gl_ABSOLUTE_HEADER([dirent.h])
- ABSOLUTE_DIRENT_H=\"$gl_cv_absolute_dirent_h\"
- DIRENT_H='dirent.h'
- UNISTD_H2='unistd.h'
- else
- DIRENT_H=
- UNISTD_H2=
+ 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) < 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
+work around the inability to open a directory.])
+ fi
+ 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
- AC_SUBST([ABSOLUTE_DIRENT_H])
- AC_SUBST([DIRENT_H])
- AC_SUBST([UNISTD_H2])
])
# Prerequisites of lib/fchdir.c.