nexmon – Blame information for rev 1

Subversion Repositories:
Rev:
Rev Author Line No. Line
1 office 1 # fcntl-o.m4 serial 3
2 dnl Copyright (C) 2006, 2009-2011 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
6  
7 dnl Written by Paul Eggert.
8  
9 # Test whether the flags O_NOATIME and O_NOFOLLOW actually work.
10 # Define HAVE_WORKING_O_NOATIME to 1 if O_NOATIME works, or to 0 otherwise.
11 # Define HAVE_WORKING_O_NOFOLLOW to 1 if O_NOFOLLOW works, or to 0 otherwise.
12 AC_DEFUN([gl_FCNTL_O_FLAGS],
13 [
14 dnl Persuade glibc <fcntl.h> to define O_NOATIME and O_NOFOLLOW.
15 dnl AC_USE_SYSTEM_EXTENSIONS was introduced in autoconf 2.60 and obsoletes
16 dnl AC_GNU_SOURCE.
17 m4_ifdef([AC_USE_SYSTEM_EXTENSIONS],
18 [AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])],
19 [AC_REQUIRE([AC_GNU_SOURCE])])
20 AC_CACHE_CHECK([for working fcntl.h], [gl_cv_header_working_fcntl_h],
21 [AC_RUN_IFELSE(
22 [AC_LANG_PROGRAM(
23 [[#include <sys/types.h>
24 #include <sys/stat.h>
25 #include <unistd.h>
26 #include <fcntl.h>
27 #ifndef O_NOATIME
28 #define O_NOATIME 0
29 #endif
30 #ifndef O_NOFOLLOW
31 #define O_NOFOLLOW 0
32 #endif
33 static int const constants[] =
34 {
35 O_CREAT, O_EXCL, O_NOCTTY, O_TRUNC, O_APPEND,
36 O_NONBLOCK, O_SYNC, O_ACCMODE, O_RDONLY, O_RDWR, O_WRONLY
37 };
38 ]],
39 [[
40 int result = !constants;
41 {
42 static char const sym[] = "conftest.sym";
43 if (symlink (".", sym) != 0)
44 result |= 2;
45 else
46 {
47 int fd = open (sym, O_RDONLY | O_NOFOLLOW);
48 if (fd >= 0)
49 {
50 close (fd);
51 result |= 4;
52 }
53 }
54 unlink (sym);
55 }
56 {
57 static char const file[] = "confdefs.h";
58 int fd = open (file, O_RDONLY | O_NOATIME);
59 if (fd < 0)
60 result |= 8;
61 else
62 {
63 struct stat st0;
64 if (fstat (fd, &st0) != 0)
65 result |= 16;
66 else
67 {
68 char c;
69 sleep (1);
70 if (read (fd, &c, 1) != 1)
71 result |= 24;
72 else
73 {
74 if (close (fd) != 0)
75 result |= 32;
76 else
77 {
78 struct stat st1;
79 if (stat (file, &st1) != 0)
80 result |= 40;
81 else
82 if (st0.st_atime != st1.st_atime)
83 result |= 64;
84 }
85 }
86 }
87 }
88 }
89 return result;]])],
90 [gl_cv_header_working_fcntl_h=yes],
91 [case $? in #(
92 4) gl_cv_header_working_fcntl_h='no (bad O_NOFOLLOW)';; #(
93 64) gl_cv_header_working_fcntl_h='no (bad O_NOATIME)';; #(
94 68) gl_cv_header_working_fcntl_h='no (bad O_NOATIME, O_NOFOLLOW)';; #(
95 *) gl_cv_header_working_fcntl_h='no';;
96 esac],
97 [gl_cv_header_working_fcntl_h=cross-compiling])])
98  
99 case $gl_cv_header_working_fcntl_h in #(
100 *O_NOATIME* | no | cross-compiling) ac_val=0;; #(
101 *) ac_val=1;;
102 esac
103 AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOATIME], [$ac_val],
104 [Define to 1 if O_NOATIME works.])
105  
106 case $gl_cv_header_working_fcntl_h in #(
107 *O_NOFOLLOW* | no | cross-compiling) ac_val=0;; #(
108 *) ac_val=1;;
109 esac
110 AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOFOLLOW], [$ac_val],
111 [Define to 1 if O_NOFOLLOW works.])
112 ])