7208f4459fe627898e0986c1934e92ca27e7e0d2
[bpt/emacs.git] / lib / openat.h
1 /* provide a replacement openat function
2 Copyright (C) 2004-2006, 2008-2013 Free Software Foundation, Inc.
3
4 This program is free software: you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 3 of the License, or
7 (at your option) any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program. If not, see <http://www.gnu.org/licenses/>. */
16
17 /* written by Jim Meyering */
18
19 #ifndef _GL_HEADER_OPENAT
20 #define _GL_HEADER_OPENAT
21
22 #include <fcntl.h>
23
24 #include <sys/types.h>
25 #include <sys/stat.h>
26 #include <unistd.h>
27 #include <stdbool.h>
28
29 #ifndef _GL_INLINE_HEADER_BEGIN
30 #error "Please include config.h first."
31 #endif
32 _GL_INLINE_HEADER_BEGIN
33
34 #if !HAVE_OPENAT
35
36 int openat_permissive (int fd, char const *file, int flags, mode_t mode,
37 int *cwd_errno);
38 bool openat_needs_fchdir (void);
39
40 #else
41
42 # define openat_permissive(Fd, File, Flags, Mode, Cwd_errno) \
43 openat (Fd, File, Flags, Mode)
44 # define openat_needs_fchdir() false
45
46 #endif
47
48 _Noreturn void openat_restore_fail (int);
49 _Noreturn void openat_save_fail (int);
50
51 /* Using these function names makes application code
52 slightly more readable than it would be with
53 fchownat (..., 0) or fchownat (..., AT_SYMLINK_NOFOLLOW). */
54
55 #if GNULIB_FCHOWNAT
56
57 # ifndef FCHOWNAT_INLINE
58 # define FCHOWNAT_INLINE _GL_INLINE
59 # endif
60
61 FCHOWNAT_INLINE int
62 chownat (int fd, char const *file, uid_t owner, gid_t group)
63 {
64 return fchownat (fd, file, owner, group, 0);
65 }
66
67 FCHOWNAT_INLINE int
68 lchownat (int fd, char const *file, uid_t owner, gid_t group)
69 {
70 return fchownat (fd, file, owner, group, AT_SYMLINK_NOFOLLOW);
71 }
72
73 #endif
74
75 #if GNULIB_FCHMODAT
76
77 # ifndef FCHMODAT_INLINE
78 # define FCHMODAT_INLINE _GL_INLINE
79 # endif
80
81 FCHMODAT_INLINE int
82 chmodat (int fd, char const *file, mode_t mode)
83 {
84 return fchmodat (fd, file, mode, 0);
85 }
86
87 FCHMODAT_INLINE int
88 lchmodat (int fd, char const *file, mode_t mode)
89 {
90 return fchmodat (fd, file, mode, AT_SYMLINK_NOFOLLOW);
91 }
92
93 #endif
94
95 #if GNULIB_STATAT
96
97 # ifndef STATAT_INLINE
98 # define STATAT_INLINE _GL_INLINE
99 # endif
100
101 STATAT_INLINE int
102 statat (int fd, char const *name, struct stat *st)
103 {
104 return fstatat (fd, name, st, 0);
105 }
106
107 STATAT_INLINE int
108 lstatat (int fd, char const *name, struct stat *st)
109 {
110 return fstatat (fd, name, st, AT_SYMLINK_NOFOLLOW);
111 }
112
113 #endif
114
115 /* For now, there are no wrappers named laccessat or leuidaccessat,
116 since gnulib doesn't support faccessat(,AT_SYMLINK_NOFOLLOW) and
117 since access rights on symlinks are of limited utility. Likewise,
118 wrappers are not provided for accessat or euidaccessat, so as to
119 avoid dragging in -lgen on some platforms. */
120
121 _GL_INLINE_HEADER_END
122
123 #endif /* _GL_HEADER_OPENAT */