3 dnl Copyright (C) 2006, 2007, 2009 Free Software Foundation, Inc.
4 dnl This file is free software; the Free Software Foundation
5 dnl gives unlimited permission to copy and/or distribute it,
6 dnl with or without modifications, as long as this notice is preserved.
8 dnl Written by Paul Eggert.
10 AC_DEFUN([gl_FCNTL_H],
12 AC_REQUIRE([gl_FCNTL_H_DEFAULTS])
13 AC_REQUIRE([gl_FCNTL_O_FLAGS])
14 gl_CHECK_NEXT_HEADERS([fcntl.h])
19 # Test whether the flags O_NOATIME and O_NOFOLLOW actually work.
20 # Define HAVE_WORKING_O_NOATIME to 1 if O_NOATIME works, or to 0 otherwise.
21 # Define HAVE_WORKING_O_NOFOLLOW to 1 if O_NOFOLLOW works, or to 0 otherwise.
22 AC_DEFUN([gl_FCNTL_O_FLAGS],
24 dnl Persuade glibc <fcntl.h> to define O_NOATIME and O_NOFOLLOW.
25 AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
26 AC_CACHE_CHECK([for working fcntl.h], [gl_cv_header_working_fcntl_h],
29 [[#include <sys/types.h>
39 static int const constants[] =
41 O_CREAT, O_EXCL, O_NOCTTY, O_TRUNC, O_APPEND,
42 O_NONBLOCK, O_SYNC, O_ACCMODE, O_RDONLY, O_RDWR, O_WRONLY
46 int status = !constants;
48 static char const sym[] = "conftest.sym";
49 if (symlink (".", sym) != 0
50 || close (open (sym, O_RDONLY | O_NOFOLLOW)) == 0)
55 static char const file[] = "confdefs.h";
56 int fd = open (file, O_RDONLY | O_NOATIME);
60 || fstat (fd, &st0) != 0
62 || read (fd, &c, 1) != 1
64 || stat (file, &st1) != 0
65 || st0.st_atime != st1.st_atime)
69 [gl_cv_header_working_fcntl_h=yes],
71 32) gl_cv_header_working_fcntl_h='no (bad O_NOFOLLOW)';; #(
72 64) gl_cv_header_working_fcntl_h='no (bad O_NOATIME)';; #(
73 96) gl_cv_header_working_fcntl_h='no (bad O_NOATIME, O_NOFOLLOW)';; #(
74 *) gl_cv_header_working_fcntl_h='no';;
76 [gl_cv_header_working_fcntl_h=cross-compiling])])
78 case $gl_cv_header_working_fcntl_h in #(
79 *O_NOATIME* | no | cross-compiling) ac_val=0;; #(
82 AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOATIME], [$ac_val],
83 [Define to 1 if O_NOATIME works.])
85 case $gl_cv_header_working_fcntl_h in #(
86 *O_NOFOLLOW* | no | cross-compiling) ac_val=0;; #(
89 AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOFOLLOW], [$ac_val],
90 [Define to 1 if O_NOFOLLOW works.])
93 AC_DEFUN([gl_FCNTL_MODULE_INDICATOR],
95 dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
96 AC_REQUIRE([gl_FCNTL_H_DEFAULTS])
97 GNULIB_[]m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./-],[ABCDEFGHIJKLMNOPQRSTUVWXYZ___])=1
100 AC_DEFUN([gl_FCNTL_H_DEFAULTS],
102 GNULIB_OPEN=0; AC_SUBST([GNULIB_OPEN])
103 GNULIB_OPENAT=0; AC_SUBST([GNULIB_OPENAT])
104 dnl Assume proper GNU behavior unless another module says otherwise.
105 HAVE_OPENAT=1; AC_SUBST([HAVE_OPENAT])
106 REPLACE_OPEN=0; AC_SUBST([REPLACE_OPEN])
107 REPLACE_OPENAT=0; AC_SUBST([REPLACE_OPENAT])