1# Configure fcntl.h.
2dnl Copyright (C) 2006 Free Software Foundation, Inc.
3dnl This file is free software; the Free Software Foundation
4dnl gives unlimited permission to copy and/or distribute it,
5dnl with or without modifications, as long as this notice is preserved.
6
7dnl Written by Paul Eggert.
8
9AC_DEFUN([gl_FCNTL_H],
10[
11  AC_CACHE_CHECK([for working fcntl.h], gl_cv_header_working_fcntl_h,
12    [AC_RUN_IFELSE(
13       [AC_LANG_PROGRAM(
14	  [[#include <sys/types.h>
15	   #include <sys/stat.h>
16	   #include <unistd.h>
17	   #include <fcntl.h>
18	   #ifndef O_NOATIME
19	    #define O_NOATIME 0
20	   #endif
21	   #ifndef O_NOFOLLOW
22	    #define O_NOFOLLOW 0
23	   #endif
24	   static int const constants[] =
25	    {
26	      O_CREAT, O_EXCL, O_NOCTTY, O_TRUNC, O_APPEND,
27	      O_NONBLOCK, O_SYNC, O_ACCMODE, O_RDONLY, O_RDWR, O_WRONLY
28	    };
29	  ]],
30	  [[
31	    int status = !constants;
32	    {
33	      static char const sym[] = "conftest.sym";
34	      if (symlink (".", sym) != 0
35		  || close (open (sym, O_RDONLY | O_NOFOLLOW)) == 0)
36		status |= 32;
37	    }
38	    {
39	      static char const file[] = "confdefs.h";
40	      int fd = open (file, O_RDONLY | O_NOATIME);
41	      char c;
42	      struct stat st0, st1;
43	      if (fd < 0
44		  || fstat (fd, &st0) != 0
45		  || sleep (1) != 0
46		  || read (fd, &c, 1) != 1
47		  || close (fd) != 0
48		  || stat (file, &st1) != 0
49		  || st0.st_atime != st1.st_atime)
50		status |= 64;
51	    }
52	    return status;]])],
53       [gl_cv_header_working_fcntl_h=yes],
54       [case $? in #(
55	32) gl_cv_header_working_fcntl_h='no (bad O_NOFOLLOW)';; #(
56	64) gl_cv_header_working_fcntl_h='no (bad O_NOATIME)';; #(
57	96) gl_cv_header_working_fcntl_h='no (bad O_NOATIME, O_NOFOLLOW)';; #(
58	 *) gl_cv_header_working_fcntl_h='no';;
59	esac],
60       [gl_cv_header_working_fcntl_h=cross-compiling])])
61
62  case $gl_cv_header_working_fcntl_h in #(
63  *O_NOATIME* | no | cross-compiling) ac_val=0;; #(
64  *) ac_val=1;;
65  esac
66  AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOATIME], [$ac_val],
67    [Define to 1 if O_NOATIME works.])
68
69  case $gl_cv_header_working_fcntl_h in #(
70  *O_NOFOLLOW* | no | cross-compiling) ac_val=0;; #(
71  *) ac_val=1;;
72  esac
73  AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOFOLLOW], [$ac_val],
74    [Define to 1 if O_NOFOLLOW works.])
75
76  gl_ABSOLUTE_HEADER([fcntl.h])
77  ABSOLUTE_FCNTL_H=\"$gl_cv_absolute_fcntl_h\"
78  AC_SUBST([ABSOLUTE_FCNTL_H])
79  FCNTL_H='fcntl.h'
80  AC_SUBST([FCNTL_H])
81])
82