xref: /freebsd/sys/sys/fcntl.h (revision aa0a1e58)
1 /*-
2  * Copyright (c) 1983, 1990, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  * (c) UNIX System Laboratories, Inc.
5  * All or some portions of this file are derived from material licensed
6  * to the University of California by American Telephone and Telegraph
7  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8  * the permission of UNIX System Laboratories, Inc.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 4. Neither the name of the University nor the names of its contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  *	@(#)fcntl.h	8.3 (Berkeley) 1/21/94
35  * $FreeBSD$
36  */
37 
38 #ifndef _SYS_FCNTL_H_
39 #define	_SYS_FCNTL_H_
40 
41 /*
42  * This file includes the definitions for open and fcntl
43  * described by POSIX for <fcntl.h>; it also includes
44  * related kernel definitions.
45  */
46 
47 #include <sys/cdefs.h>
48 #include <sys/_types.h>
49 
50 #ifndef _MODE_T_DECLARED
51 typedef	__mode_t	mode_t;
52 #define	_MODE_T_DECLARED
53 #endif
54 
55 #ifndef _OFF_T_DECLARED
56 typedef	__off_t		off_t;
57 #define	_OFF_T_DECLARED
58 #endif
59 
60 #ifndef _PID_T_DECLARED
61 typedef	__pid_t		pid_t;
62 #define	_PID_T_DECLARED
63 #endif
64 
65 /*
66  * File status flags: these are used by open(2), fcntl(2).
67  * They are also used (indirectly) in the kernel file structure f_flags,
68  * which is a superset of the open/fcntl flags.  Open flags and f_flags
69  * are inter-convertible using OFLAGS(fflags) and FFLAGS(oflags).
70  * Open/fcntl flags begin with O_; kernel-internal flags begin with F.
71  */
72 /* open-only flags */
73 #define	O_RDONLY	0x0000		/* open for reading only */
74 #define	O_WRONLY	0x0001		/* open for writing only */
75 #define	O_RDWR		0x0002		/* open for reading and writing */
76 #define	O_ACCMODE	0x0003		/* mask for above modes */
77 
78 /*
79  * Kernel encoding of open mode; separate read and write bits that are
80  * independently testable: 1 greater than the above.
81  *
82  * XXX
83  * FREAD and FWRITE are excluded from the #ifdef _KERNEL so that TIOCFLUSH,
84  * which was documented to use FREAD/FWRITE, continues to work.
85  */
86 #if __BSD_VISIBLE
87 #define	FREAD		0x0001
88 #define	FWRITE		0x0002
89 #endif
90 #define	O_NONBLOCK	0x0004		/* no delay */
91 #define	O_APPEND	0x0008		/* set append mode */
92 #if __BSD_VISIBLE
93 #define	O_SHLOCK	0x0010		/* open with shared file lock */
94 #define	O_EXLOCK	0x0020		/* open with exclusive file lock */
95 #define	O_ASYNC		0x0040		/* signal pgrp when data ready */
96 #define	O_FSYNC		0x0080		/* synchronous writes */
97 #endif
98 #define	O_SYNC		0x0080		/* POSIX synonym for O_FSYNC */
99 #if __BSD_VISIBLE
100 #define	O_NOFOLLOW	0x0100		/* don't follow symlinks */
101 #endif
102 #define	O_CREAT		0x0200		/* create if nonexistent */
103 #define	O_TRUNC		0x0400		/* truncate to zero length */
104 #define	O_EXCL		0x0800		/* error if already exists */
105 #ifdef _KERNEL
106 #define	FHASLOCK	0x4000		/* descriptor holds advisory lock */
107 #endif
108 
109 /* Defined by POSIX 1003.1; BSD default, but must be distinct from O_RDONLY. */
110 #define	O_NOCTTY	0x8000		/* don't assign controlling terminal */
111 
112 #if __BSD_VISIBLE
113 /* Attempt to bypass buffer cache */
114 #define O_DIRECT	0x00010000
115 #endif
116 
117 /* Defined by POSIX Extended API Set Part 2 */
118 #if __BSD_VISIBLE
119 #define	O_DIRECTORY	0x00020000	/* Fail if not directory */
120 #define	O_EXEC		0x00040000	/* Open for execute only */
121 #endif
122 #ifdef	_KERNEL
123 #define	FEXEC		O_EXEC
124 #endif
125 
126 /* Defined by POSIX 1003.1-2008; BSD default, but reserve for future use. */
127 #if __POSIX_VISIBLE >= 200809
128 #define	O_TTY_INIT	0x00080000	/* Restore default termios attributes */
129 #endif
130 
131 /*
132  * XXX missing O_DSYNC, O_RSYNC.
133  */
134 
135 #ifdef _KERNEL
136 /* convert from open() flags to/from fflags; convert O_RD/WR to FREAD/FWRITE */
137 #define	FFLAGS(oflags)	((oflags) + 1)
138 #define	OFLAGS(fflags)	((fflags) - 1)
139 
140 /* bits to save after open */
141 #define	FMASK	(FREAD|FWRITE|FAPPEND|FASYNC|FFSYNC|FNONBLOCK|O_DIRECT|FEXEC)
142 /* bits settable by fcntl(F_SETFL, ...) */
143 #define	FCNTLFLAGS	(FAPPEND|FASYNC|FFSYNC|FNONBLOCK|FRDAHEAD|O_DIRECT)
144 
145 #if defined(COMPAT_FREEBSD7) || defined(COMPAT_FREEBSD6) || \
146     defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4)
147 /*
148  * Set by shm_open(3) in older libc's to get automatic MAP_ASYNC
149  * behavior for POSIX shared memory objects (which are otherwise
150  * implemented as plain files).
151  */
152 #define	FPOSIXSHM	O_NOFOLLOW
153 #undef FCNTLFLAGS
154 #define	FCNTLFLAGS	(FAPPEND|FASYNC|FFSYNC|FNONBLOCK|FPOSIXSHM|FRDAHEAD| \
155 			 O_DIRECT)
156 #endif
157 #endif
158 
159 /*
160  * The O_* flags used to have only F* names, which were used in the kernel
161  * and by fcntl.  We retain the F* names for the kernel f_flag field
162  * and for backward compatibility for fcntl.  These flags are deprecated.
163  */
164 #if __BSD_VISIBLE
165 #define	FAPPEND		O_APPEND	/* kernel/compat */
166 #define	FASYNC		O_ASYNC		/* kernel/compat */
167 #define	FFSYNC		O_FSYNC		/* kernel */
168 #define	FNONBLOCK	O_NONBLOCK	/* kernel */
169 #define	FNDELAY		O_NONBLOCK	/* compat */
170 #define	O_NDELAY	O_NONBLOCK	/* compat */
171 #endif
172 
173 /*
174  * We are out of bits in f_flag (which is a short).  However,
175  * the flag bits not set in FMASK are only meaningful in the
176  * initial open syscall.  Those bits can thus be given a
177  * different meaning for fcntl(2).
178  */
179 #if __BSD_VISIBLE
180 /* Read ahead */
181 #define	FRDAHEAD	O_CREAT
182 #endif
183 
184 /* Defined by POSIX Extended API Set Part 2 */
185 #if __BSD_VISIBLE
186 /*
187  * Magic value that specify the use of the current working directory
188  * to determine the target of relative file paths in the openat() and
189  * similar syscalls.
190  */
191 #define	AT_FDCWD		-100
192 
193 /*
194  * Miscellaneous flags for the *at() syscalls.
195  */
196 #define	AT_EACCESS		0x100	/* Check access using effective user and group ID */
197 #define	AT_SYMLINK_NOFOLLOW	0x200   /* Do not follow symbolic links */
198 #define	AT_SYMLINK_FOLLOW	0x400	/* Follow symbolic link */
199 #define	AT_REMOVEDIR		0x800	/* Remove directory instead of file */
200 #endif
201 
202 /*
203  * Constants used for fcntl(2)
204  */
205 
206 /* command values */
207 #define	F_DUPFD		0		/* duplicate file descriptor */
208 #define	F_GETFD		1		/* get file descriptor flags */
209 #define	F_SETFD		2		/* set file descriptor flags */
210 #define	F_GETFL		3		/* get file status flags */
211 #define	F_SETFL		4		/* set file status flags */
212 #if __BSD_VISIBLE || __XSI_VISIBLE || __POSIX_VISIBLE >= 200112
213 #define	F_GETOWN	5		/* get SIGIO/SIGURG proc/pgrp */
214 #define F_SETOWN	6		/* set SIGIO/SIGURG proc/pgrp */
215 #endif
216 #define	F_OGETLK	7		/* get record locking information */
217 #define	F_OSETLK	8		/* set record locking information */
218 #define	F_OSETLKW	9		/* F_SETLK; wait if blocked */
219 #define	F_DUP2FD	10		/* duplicate file descriptor to arg */
220 #define	F_GETLK		11		/* get record locking information */
221 #define	F_SETLK		12		/* set record locking information */
222 #define	F_SETLKW	13		/* F_SETLK; wait if blocked */
223 #define	F_SETLK_REMOTE	14		/* debugging support for remote locks */
224 #define	F_READAHEAD	15		/* read ahead */
225 #define	F_RDAHEAD	16		/* Darwin compatible read ahead */
226 
227 /* file descriptor flags (F_GETFD, F_SETFD) */
228 #define	FD_CLOEXEC	1		/* close-on-exec flag */
229 
230 /* record locking flags (F_GETLK, F_SETLK, F_SETLKW) */
231 #define	F_RDLCK		1		/* shared or read lock */
232 #define	F_UNLCK		2		/* unlock */
233 #define	F_WRLCK		3		/* exclusive or write lock */
234 #define	F_UNLCKSYS	4		/* purge locks for a given system ID */
235 #define	F_CANCEL	5		/* cancel an async lock request */
236 #ifdef _KERNEL
237 #define	F_WAIT		0x010		/* Wait until lock is granted */
238 #define	F_FLOCK		0x020	 	/* Use flock(2) semantics for lock */
239 #define	F_POSIX		0x040	 	/* Use POSIX semantics for lock */
240 #define	F_REMOTE	0x080		/* Lock owner is remote NFS client */
241 #define F_NOINTR	0x100		/* Ignore signals when waiting */
242 #endif
243 
244 /*
245  * Advisory file segment locking data type -
246  * information passed to system by user
247  */
248 struct flock {
249 	off_t	l_start;	/* starting offset */
250 	off_t	l_len;		/* len = 0 means until end of file */
251 	pid_t	l_pid;		/* lock owner */
252 	short	l_type;		/* lock type: read/write, etc. */
253 	short	l_whence;	/* type of l_start */
254 	int	l_sysid;	/* remote system id or zero for local */
255 };
256 
257 /*
258  * Old advisory file segment locking data type,
259  * before adding l_sysid.
260  */
261 struct oflock {
262 	off_t	l_start;	/* starting offset */
263 	off_t	l_len;		/* len = 0 means until end of file */
264 	pid_t	l_pid;		/* lock owner */
265 	short	l_type;		/* lock type: read/write, etc. */
266 	short	l_whence;	/* type of l_start */
267 };
268 
269 
270 #if __BSD_VISIBLE
271 /* lock operations for flock(2) */
272 #define	LOCK_SH		0x01		/* shared file lock */
273 #define	LOCK_EX		0x02		/* exclusive file lock */
274 #define	LOCK_NB		0x04		/* don't block when locking */
275 #define	LOCK_UN		0x08		/* unlock file */
276 #endif
277 
278 /*
279  * XXX missing posix_fadvise() and posix_fallocate(), and POSIX_FADV_* macros.
280  */
281 
282 #ifndef _KERNEL
283 __BEGIN_DECLS
284 int	open(const char *, int, ...);
285 int	creat(const char *, mode_t);
286 int	fcntl(int, int, ...);
287 #if __BSD_VISIBLE || __POSIX_VISIBLE >= 200809
288 int	openat(int, const char *, int, ...);
289 #endif
290 #if __BSD_VISIBLE
291 int	flock(int, int);
292 #endif
293 __END_DECLS
294 #endif
295 
296 #endif /* !_SYS_FCNTL_H_ */
297