1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
|
# serial 27
# See if we need to use our replacement for Solaris' openat et al functions.
dnl Copyright (C) 2004-2009 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.
# Written by Jim Meyering.
AC_DEFUN([gl_FUNC_OPENAT],
[
AC_REQUIRE([gl_FCNTL_H_DEFAULTS])
GNULIB_OPENAT=1
AC_REQUIRE([gl_SYS_STAT_H_DEFAULTS])
GNULIB_FCHMODAT=1
GNULIB_FSTATAT=1
GNULIB_MKDIRAT=1
AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
GNULIB_FCHOWNAT=1
GNULIB_UNLINKAT=1
AC_LIBOBJ([openat-proc])
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
AC_CHECK_FUNCS_ONCE([lchmod])
AC_REPLACE_FUNCS([fchmodat fstatat mkdirat openat unlinkat])
AC_REQUIRE([AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK])
AC_REQUIRE([gl_FUNC_UNLINK])
case $ac_cv_func_openat+$ac_cv_func_lstat_dereferences_slashed_symlink in
yes+yes)
# GNU/Hurd has unlinkat, but it has the same bug as unlink.
if test $REPLACE_UNLINK = 1; then
AC_LIBOBJ([unlinkat])
REPLACE_UNLINKAT=1
fi ;;
yes+*)
# Solaris 9 has *at functions, but uniformly mishandles trailing
# slash in all of them.
AC_LIBOBJ([openat])
REPLACE_OPENAT=1
AC_LIBOBJ([fstatat])
REPLACE_FSTATAT=1
AC_LIBOBJ([unlinkat])
REPLACE_UNLINKAT=1
;;
*)
HAVE_OPENAT=0
HAVE_UNLINKAT=0 # No known system with unlinkat but not openat
HAVE_FSTATAT=0 # No known system with fstatat but not openat
gl_PREREQ_OPENAT;;
esac
if test $ac_cv_func_fchmodat != yes; then
HAVE_FCHMODAT=0
fi
if test $ac_cv_func_mkdirat != yes; then
HAVE_MKDIRAT=0
fi
gl_FUNC_FCHOWNAT
])
# gl_FUNC_FCHOWNAT_DEREF_BUG([ACTION-IF-BUGGY[, ACTION-IF-NOT_BUGGY]])
AC_DEFUN([gl_FUNC_FCHOWNAT_DEREF_BUG],
[
AC_CACHE_CHECK([whether fchownat works with AT_SYMLINK_NOFOLLOW],
gl_cv_func_fchownat_nofollow_works,
[
gl_dangle=conftest.dangle
# Remove any remnants of a previous test.
rm -f $gl_dangle
# Arrange for deletion of the temporary file this test creates.
ac_clean_files="$ac_clean_files $gl_dangle"
ln -s conftest.no-such $gl_dangle
AC_RUN_IFELSE(
[AC_LANG_SOURCE(
[[
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/types.h>
int
main ()
{
return (fchownat (AT_FDCWD, "$gl_dangle", -1, getgid (),
AT_SYMLINK_NOFOLLOW) != 0
&& errno == ENOENT);
}
]])],
[gl_cv_func_fchownat_nofollow_works=yes],
[gl_cv_func_fchownat_nofollow_works=no],
[gl_cv_func_fchownat_nofollow_works=no],
)
])
AS_IF([test $gl_cv_func_fchownat_nofollow_works = no], [$1], [$2])
])
# If we have the fchownat function, and it has the bug (in glibc-2.4)
# that it dereferences symlinks even with AT_SYMLINK_NOFOLLOW, then
# use the replacement function.
# Also use the replacement function if fchownat is simply not available.
AC_DEFUN([gl_FUNC_FCHOWNAT],
[
AC_REQUIRE([gl_FUNC_CHOWN])
AC_CHECK_FUNC([fchownat],
[gl_FUNC_FCHOWNAT_DEREF_BUG([REPLACE_FCHOWNAT=1
AC_DEFINE([FCHOWNAT_NOFOLLOW_BUG], [1], [Define to 1 if your
platform has fchownat, but it cannot perform lchown tasks.])])],
[HAVE_FCHOWNAT=0])
if test $REPLACE_CHOWN = 1; then
REPLACE_FCHOWNAT=1
fi
if test $HAVE_FCHOWNAT = 0 || test $REPLACE_FCHOWNAT = 1; then
AC_LIBOBJ([fchownat])
fi
])
AC_DEFUN([gl_PREREQ_OPENAT],
[
AC_REQUIRE([AC_C_INLINE])
AC_REQUIRE([gl_PROMOTED_TYPE_MODE_T])
:
])
|
