1/* Copyright (C) 1991-2016 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library 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 GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <http://www.gnu.org/licenses/>. */
17
18/*
19 * POSIX Standard: 6.5 File Control Operations <fcntl.h>
20 */
21
22#ifndef _FCNTL_H
23#define _FCNTL_H 1
24
25#include <features.h>
26
27/* This must be early so <bits/fcntl.h> can define types winningly. */
28__BEGIN_DECLS
29
30/* Get __mode_t, __dev_t and __off_t .*/
31#include <bits/types.h>
32
33/* Get the definitions of O_*, F_*, FD_*: all the
34 numbers and flag bits for `open', `fcntl', et al. */
35#include <bits/fcntl.h>
36
37/* Detect if open needs mode as a third argument (or for openat as a fourth
38 argument). */
39#ifdef __O_TMPFILE
40# define __OPEN_NEEDS_MODE(oflag) \
41 (((oflag) & O_CREAT) != 0 || ((oflag) & __O_TMPFILE) == __O_TMPFILE)
42#else
43# define __OPEN_NEEDS_MODE(oflag) (((oflag) & O_CREAT) != 0)
44#endif
45
46/* POSIX.1-2001 specifies that these types are defined by <fcntl.h>.
47 Earlier POSIX standards permitted any type ending in `_t' to be defined
48 by any POSIX header, so we don't conditionalize the definitions here. */
49#ifndef __mode_t_defined
50typedef __mode_t mode_t;
51# define __mode_t_defined
52#endif
53
54#ifndef __off_t_defined
55# ifndef __USE_FILE_OFFSET64
56typedef __off_t off_t;
57# else
58typedef __off64_t off_t;
59# endif
60# define __off_t_defined
61#endif
62
63#if defined __USE_LARGEFILE64 && !defined __off64_t_defined
64typedef __off64_t off64_t;
65# define __off64_t_defined
66#endif
67
68#ifndef __pid_t_defined
69typedef __pid_t pid_t;
70# define __pid_t_defined
71#endif
72
73/* For XPG all symbols from <sys/stat.h> should also be available. */
74#ifdef __USE_XOPEN2K8
75# define __need_timespec
76# include <time.h>
77#endif
78#if defined __USE_XOPEN || defined __USE_XOPEN2K8
79# include <bits/stat.h>
80
81# define S_IFMT __S_IFMT
82# define S_IFDIR __S_IFDIR
83# define S_IFCHR __S_IFCHR
84# define S_IFBLK __S_IFBLK
85# define S_IFREG __S_IFREG
86# ifdef __S_IFIFO
87# define S_IFIFO __S_IFIFO
88# endif
89# ifdef __S_IFLNK
90# define S_IFLNK __S_IFLNK
91# endif
92# if (defined __USE_UNIX98 || defined __USE_XOPEN2K8) && defined __S_IFSOCK
93# define S_IFSOCK __S_IFSOCK
94# endif
95
96/* Protection bits. */
97
98# define S_ISUID __S_ISUID /* Set user ID on execution. */
99# define S_ISGID __S_ISGID /* Set group ID on execution. */
100
101# if defined __USE_MISC || defined __USE_XOPEN
102/* Save swapped text after use (sticky bit). This is pretty well obsolete. */
103# define S_ISVTX __S_ISVTX
104# endif
105
106# define S_IRUSR __S_IREAD /* Read by owner. */
107# define S_IWUSR __S_IWRITE /* Write by owner. */
108# define S_IXUSR __S_IEXEC /* Execute by owner. */
109/* Read, write, and execute by owner. */
110# define S_IRWXU (__S_IREAD|__S_IWRITE|__S_IEXEC)
111
112# define S_IRGRP (S_IRUSR >> 3) /* Read by group. */
113# define S_IWGRP (S_IWUSR >> 3) /* Write by group. */
114# define S_IXGRP (S_IXUSR >> 3) /* Execute by group. */
115/* Read, write, and execute by group. */
116# define S_IRWXG (S_IRWXU >> 3)
117
118# define S_IROTH (S_IRGRP >> 3) /* Read by others. */
119# define S_IWOTH (S_IWGRP >> 3) /* Write by others. */
120# define S_IXOTH (S_IXGRP >> 3) /* Execute by others. */
121/* Read, write, and execute by others. */
122# define S_IRWXO (S_IRWXG >> 3)
123#endif
124
125#ifdef __USE_MISC
126# ifndef R_OK /* Verbatim from <unistd.h>. Ugh. */
127/* Values for the second argument to access.
128 These may be OR'd together. */
129# define R_OK 4 /* Test for read permission. */
130# define W_OK 2 /* Test for write permission. */
131# define X_OK 1 /* Test for execute permission. */
132# define F_OK 0 /* Test for existence. */
133# endif
134#endif /* Use misc. */
135
136/* XPG wants the following symbols. <stdio.h> has the same definitions. */
137#if defined __USE_XOPEN || defined __USE_XOPEN2K8
138# define SEEK_SET 0 /* Seek from beginning of file. */
139# define SEEK_CUR 1 /* Seek from current position. */
140# define SEEK_END 2 /* Seek from end of file. */
141#endif /* XPG */
142
143/* Do the file control operation described by CMD on FD.
144 The remaining arguments are interpreted depending on CMD.
145
146 This function is a cancellation point and therefore not marked with
147 __THROW. */
148extern int fcntl (int __fd, int __cmd, ...);
149
150/* Open FILE and return a new file descriptor for it, or -1 on error.
151 OFLAG determines the type of access used. If O_CREAT or O_TMPFILE is set
152 in OFLAG, the third argument is taken as a `mode_t', the mode of the
153 created file.
154
155 This function is a cancellation point and therefore not marked with
156 __THROW. */
157#ifndef __USE_FILE_OFFSET64
158extern int open (const char *__file, int __oflag, ...) __nonnull ((1));
159#else
160# ifdef __REDIRECT
161extern int __REDIRECT (open, (const char *__file, int __oflag, ...), open64)
162 __nonnull ((1));
163# else
164# define open open64
165# endif
166#endif
167#ifdef __USE_LARGEFILE64
168extern int open64 (const char *__file, int __oflag, ...) __nonnull ((1));
169#endif
170
171#ifdef __USE_ATFILE
172/* Similar to `open' but a relative path name is interpreted relative to
173 the directory for which FD is a descriptor.
174
175 NOTE: some other `openat' implementation support additional functionality
176 through this interface, especially using the O_XATTR flag. This is not
177 yet supported here.
178
179 This function is a cancellation point and therefore not marked with
180 __THROW. */
181# ifndef __USE_FILE_OFFSET64
182extern int openat (int __fd, const char *__file, int __oflag, ...)
183 __nonnull ((2));
184# else
185# ifdef __REDIRECT
186extern int __REDIRECT (openat, (int __fd, const char *__file, int __oflag,
187 ...), openat64) __nonnull ((2));
188# else
189# define openat openat64
190# endif
191# endif
192# ifdef __USE_LARGEFILE64
193extern int openat64 (int __fd, const char *__file, int __oflag, ...)
194 __nonnull ((2));
195# endif
196#endif
197
198/* Create and open FILE, with mode MODE. This takes an `int' MODE
199 argument because that is what `mode_t' will be widened to.
200
201 This function is a cancellation point and therefore not marked with
202 __THROW. */
203#ifndef __USE_FILE_OFFSET64
204extern int creat (const char *__file, mode_t __mode) __nonnull ((1));
205#else
206# ifdef __REDIRECT
207extern int __REDIRECT (creat, (const char *__file, mode_t __mode),
208 creat64) __nonnull ((1));
209# else
210# define creat creat64
211# endif
212#endif
213#ifdef __USE_LARGEFILE64
214extern int creat64 (const char *__file, mode_t __mode) __nonnull ((1));
215#endif
216
217#if !defined F_LOCK && (defined __USE_MISC || (defined __USE_XOPEN_EXTENDED \
218 && !defined __USE_POSIX))
219/* NOTE: These declarations also appear in <unistd.h>; be sure to keep both
220 files consistent. Some systems have them there and some here, and some
221 software depends on the macros being defined without including both. */
222
223/* `lockf' is a simpler interface to the locking facilities of `fcntl'.
224 LEN is always relative to the current file position.
225 The CMD argument is one of the following. */
226
227# define F_ULOCK 0 /* Unlock a previously locked region. */
228# define F_LOCK 1 /* Lock a region for exclusive use. */
229# define F_TLOCK 2 /* Test and lock a region for exclusive use. */
230# define F_TEST 3 /* Test a region for other processes locks. */
231
232# ifndef __USE_FILE_OFFSET64
233extern int lockf (int __fd, int __cmd, off_t __len);
234# else
235# ifdef __REDIRECT
236extern int __REDIRECT (lockf, (int __fd, int __cmd, __off64_t __len), lockf64);
237# else
238# define lockf lockf64
239# endif
240# endif
241# ifdef __USE_LARGEFILE64
242extern int lockf64 (int __fd, int __cmd, off64_t __len);
243# endif
244#endif
245
246#ifdef __USE_XOPEN2K
247/* Advice the system about the expected behaviour of the application with
248 respect to the file associated with FD. */
249# ifndef __USE_FILE_OFFSET64
250extern int posix_fadvise (int __fd, off_t __offset, off_t __len,
251 int __advise) __THROW;
252# else
253 # ifdef __REDIRECT_NTH
254extern int __REDIRECT_NTH (posix_fadvise, (int __fd, __off64_t __offset,
255 __off64_t __len, int __advise),
256 posix_fadvise64);
257# else
258# define posix_fadvise posix_fadvise64
259# endif
260# endif
261# ifdef __USE_LARGEFILE64
262extern int posix_fadvise64 (int __fd, off64_t __offset, off64_t __len,
263 int __advise) __THROW;
264# endif
265
266
267/* Reserve storage for the data of the file associated with FD.
268
269 This function is a possible cancellation point and therefore not
270 marked with __THROW. */
271# ifndef __USE_FILE_OFFSET64
272extern int posix_fallocate (int __fd, off_t __offset, off_t __len);
273# else
274 # ifdef __REDIRECT
275extern int __REDIRECT (posix_fallocate, (int __fd, __off64_t __offset,
276 __off64_t __len),
277 posix_fallocate64);
278# else
279# define posix_fallocate posix_fallocate64
280# endif
281# endif
282# ifdef __USE_LARGEFILE64
283extern int posix_fallocate64 (int __fd, off64_t __offset, off64_t __len);
284# endif
285#endif
286
287
288/* Define some inlines helping to catch common problems. */
289#if __USE_FORTIFY_LEVEL > 0 && defined __fortify_function \
290 && defined __va_arg_pack_len
291# include <bits/fcntl2.h>
292#endif
293
294__END_DECLS
295
296#endif /* fcntl.h */
297