xref: /netbsd/sys/sys/fcntl.h (revision 1dc79398)
1 /*	$NetBSD: fcntl.h,v 1.55 2023/07/10 02:31:55 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 1983, 1990, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  *	@(#)fcntl.h	8.3 (Berkeley) 1/21/94
37  */
38 
39 #ifndef _SYS_FCNTL_H_
40 #define	_SYS_FCNTL_H_
41 
42 /*
43  * This file includes the definitions for open and fcntl
44  * described by POSIX for <fcntl.h>; it also includes
45  * related kernel definitions.
46  */
47 
48 #ifndef _KERNEL
49 #include <sys/featuretest.h>
50 #include <sys/types.h>
51 #if defined(_XOPEN_SOURCE)
52 #include <sys/stat.h>
53 #endif /* _XOPEN_SOURCE */
54 #endif /* !_KERNEL */
55 
56 /*
57  * File status flags: these are used by open(2), fcntl(2).
58  * They are also used (indirectly) in the kernel file structure f_flags,
59  * which is a superset of the open/fcntl flags.  Open flags and f_flags
60  * are inter-convertible using OFLAGS(fflags) and FFLAGS(oflags).
61  * Open/fcntl flags begin with O_; kernel-internal flags begin with F.
62  */
63 /* open-only flags */
64 #define	O_RDONLY	0x00000000	/* open for reading only */
65 #define	O_WRONLY	0x00000001	/* open for writing only */
66 #define	O_RDWR		0x00000002	/* open for reading and writing */
67 #define	O_ACCMODE	0x00000003	/* mask for above modes */
68 
69 /*
70  * Kernel encoding of open mode; separate read and write bits that are
71  * independently testable: 1 greater than the above.
72  *
73  * XXX
74  * FREAD and FWRITE are excluded from the #ifdef _KERNEL so that TIOCFLUSH,
75  * which was documented to use FREAD/FWRITE, continues to work.
76  */
77 #if defined(_NETBSD_SOURCE)
78 #define	FREAD		0x00000001
79 #define	FWRITE		0x00000002
80 #endif
81 #define	O_NONBLOCK	0x00000004	/* no delay */
82 #define	O_APPEND	0x00000008	/* set append mode */
83 #if defined(_NETBSD_SOURCE)
84 #define	O_SHLOCK	0x00000010	/* open with shared file lock */
85 #define	O_EXLOCK	0x00000020	/* open with exclusive file lock */
86 #define	O_ASYNC		0x00000040	/* signal pgrp when data ready */
87 #endif
88 #if (_POSIX_C_SOURCE - 0) >= 199309L || \
89     (defined(_XOPEN_SOURCE) && defined(_XOPEN_SOURCE_EXTENDED)) || \
90     (_XOPEN_SOURCE - 0) >= 500 || defined(_NETBSD_SOURCE)
91 #define	O_SYNC		0x00000080	/* synchronous writes */
92 #endif
93 #if (_POSIX_C_SOURCE - 0) >= 200809L || defined(_NETBSD_SOURCE)
94 #define	O_NOFOLLOW	0x00000100	/* don't follow symlinks on the last */
95 					/* path component */
96 #endif
97 #define	O_CREAT		0x00000200	/* create if nonexistent */
98 #define	O_TRUNC		0x00000400	/* truncate to zero length */
99 #define	O_EXCL		0x00000800	/* error if already exists */
100 
101 /* defined by POSIX 1003.1; BSD default, but required to be bitwise distinct */
102 #define	O_NOCTTY	0x00008000	/* don't assign controlling terminal */
103 
104 #if (_POSIX_C_SOURCE - 0) >= 199309L || (_XOPEN_SOURCE - 0) >= 500 || \
105     defined(_NETBSD_SOURCE)
106 #define	O_DSYNC		0x00010000	/* write: I/O data completion */
107 #define	O_RSYNC		0x00020000	/* read: I/O completion as for write */
108 #endif
109 
110 #if defined(_NETBSD_SOURCE)
111 #define	O_ALT_IO	0x00040000	/* use alternate i/o semantics */
112 #define	O_DIRECT	0x00080000	/* direct I/O hint */
113 #endif
114 
115 #define	O_DIRECTORY	0x00200000	/* fail if not a directory */
116 #define	O_CLOEXEC	0x00400000	/* set close on exec */
117 #if (_POSIX_C_SOURCE - 0) >= 200809L || (_XOPEN_SOURCE - 0 >= 700) || \
118     defined(_NETBSD_SOURCE)
119 #define	O_SEARCH	0x00800000	/* skip search permission checks */
120 #endif
121 #if defined(_NETBSD_SOURCE)
122 #define	O_NOSIGPIPE	0x01000000	/* don't deliver sigpipe */
123 #define	O_REGULAR	0x02000000	/* fail if not a regular file */
124 #define	O_EXEC		0x04000000	/* open for executing only */
125 #endif
126 
127 #ifdef _KERNEL
128 /* convert from open() flags to/from fflags; convert O_RD/WR to FREAD/FWRITE */
129 #define	FFLAGS(oflags)	((oflags) + 1)
130 #define	OFLAGS(fflags)	((fflags) - 1)
131 
132 /* all bits settable during open(2) */
133 #define	O_MASK		(O_ACCMODE|O_NONBLOCK|O_APPEND|O_SHLOCK|O_EXLOCK|\
134 			 O_ASYNC|O_SYNC|O_CREAT|O_TRUNC|O_EXCL|O_DSYNC|\
135 			 O_RSYNC|O_NOCTTY|O_ALT_IO|O_NOFOLLOW|O_DIRECT|\
136 			 O_DIRECTORY|O_CLOEXEC|O_NOSIGPIPE|O_REGULAR|O_EXEC)
137 
138 #define	FEXEC		O_EXEC
139 #define	FMARK		0x00001000	/* mark during gc() */
140 #define	FDEFER		0x00002000	/* defer for next gc pass */
141 #define	FHASLOCK	0x00004000	/* descriptor holds advisory lock */
142 #define	FSCAN		0x00100000	/* scan during gc passes */
143 #define	FSILENT		0x40000000	/* suppress kernel error messages */
144 #define	FKIOCTL		0x80000000	/* kernel originated ioctl */
145 /* bits settable by fcntl(F_SETFL, ...) */
146 #define	FCNTLFLAGS	(FAPPEND|FASYNC|FFSYNC|FNONBLOCK|FDSYNC|FRSYNC|FALTIO|\
147 			 FDIRECT|FNOSIGPIPE)
148 /* bits to save after open(2) */
149 #define	FMASK		(FREAD|FWRITE|FCNTLFLAGS|FEXEC)
150 #endif /* _KERNEL */
151 
152 /*
153  * The O_* flags used to have only F* names, which were used in the kernel
154  * and by fcntl.  We retain the F* names for the kernel f_flags field
155  * and for backward compatibility for fcntl.
156  */
157 #if defined(_NETBSD_SOURCE)
158 #define	FAPPEND		O_APPEND	/* kernel/compat */
159 #define	FASYNC		O_ASYNC		/* kernel/compat */
160 #define	O_FSYNC		O_SYNC		/* compat */
161 #define	FNDELAY		O_NONBLOCK	/* compat */
162 #define	O_NDELAY	O_NONBLOCK	/* compat */
163 #endif
164 #if defined(_KERNEL)
165 #define	FNOSIGPIPE	O_NOSIGPIPE	/* kernel */
166 #define	FNONBLOCK	O_NONBLOCK	/* kernel */
167 #define	FFSYNC		O_SYNC		/* kernel */
168 #define	FDSYNC		O_DSYNC		/* kernel */
169 #define	FRSYNC		O_RSYNC		/* kernel */
170 #define	FALTIO		O_ALT_IO	/* kernel */
171 #define	FDIRECT		O_DIRECT	/* kernel */
172 #endif
173 
174 /*
175  * Constants used for fcntl(2)
176  */
177 
178 /* command values */
179 #define	F_DUPFD		0		/* duplicate file descriptor */
180 #define	F_GETFD		1		/* get file descriptor flags */
181 #define	F_SETFD		2		/* set file descriptor flags */
182 #define	F_GETFL		3		/* get file status flags */
183 #define	F_SETFL		4		/* set file status flags */
184 #if (_POSIX_C_SOURCE - 0) >= 200112L || (_XOPEN_SOURCE - 0) >= 500 || \
185     defined(_NETBSD_SOURCE)
186 #define	F_GETOWN	5		/* get SIGIO/SIGURG proc/pgrp */
187 #define	F_SETOWN	6		/* set SIGIO/SIGURG proc/pgrp */
188 #endif
189 #define	F_GETLK		7		/* get record locking information */
190 #define	F_SETLK		8		/* set record locking information */
191 #define	F_SETLKW	9		/* F_SETLK; wait if blocked */
192 #if defined(_NETBSD_SOURCE)
193 #define	F_CLOSEM	10		/* close all fds >= to the one given */
194 #define	F_MAXFD		11		/* return the max open fd */
195 #endif
196 #if (_POSIX_C_SOURCE - 0) >= 200809L || defined(_NETBSD_SOURCE)
197 #define	F_DUPFD_CLOEXEC	12		/* close on exec duplicated fd */
198 #endif
199 #if defined(_NETBSD_SOURCE)
200 #define	F_GETNOSIGPIPE	13		/* get SIGPIPE disposition */
201 #define	F_SETNOSIGPIPE	14		/* set SIGPIPE disposition */
202 #define	F_GETPATH	15		/* get pathname associated with fd */
203 #define	F_ADD_SEALS	16		/* set seals */
204 #define	F_GET_SEALS	17		/* get seals */
205 #endif
206 
207 /* file descriptor flags (F_GETFD, F_SETFD) */
208 #define	FD_CLOEXEC	1		/* close-on-exec flag */
209 
210 /* record locking flags (F_GETLK, F_SETLK, F_SETLKW) */
211 #define	F_RDLCK		1		/* shared or read lock */
212 #define	F_UNLCK		2		/* unlock */
213 #define	F_WRLCK		3		/* exclusive or write lock */
214 #ifdef _KERNEL
215 #define	F_WAIT		0x010		/* Wait until lock is granted */
216 #define	F_FLOCK		0x020	 	/* Use flock(2) semantics for lock */
217 #define	F_POSIX		0x040	 	/* Use POSIX semantics for lock */
218 #endif
219 
220 /* types of seals (F_ADD_SEALS, F_GET_SEALS) */
221 #if defined(_NETBSD_SOURCE)
222 #define	F_SEAL_SEAL		0x0001	/* prevent further seals from being set */
223 #define	F_SEAL_SHRINK		0x0002	/* prevent file from shrinking */
224 #define	F_SEAL_GROW		0x0004	/* prevent file from growing */
225 #define	F_SEAL_WRITE		0x0008	/* prevent writes */
226 #define	F_SEAL_FUTURE_WRITE	0x0010	/* prevent future writes while mapped */
227 #endif
228 
229 /* Constants for fcntl's passed to the underlying fs - like ioctl's. */
230 #if defined(_NETBSD_SOURCE)
231 #define	F_PARAM_MASK	0xfff
232 #define	F_PARAM_LEN(x)	(((x) >> 16) & F_PARAM_MASK)
233 #define	F_PARAM_MAX	4095
234 #define	F_FSCTL		(int)0x80000000	/* This fcntl goes to the fs */
235 #define	F_FSVOID	(int)0x40000000	/* no parameters */
236 #define	F_FSOUT		(int)0x20000000	/* copy out parameter */
237 #define	F_FSIN		(int)0x10000000	/* copy in parameter */
238 #define	F_FSINOUT	(F_FSIN | F_FSOUT)
239 #define	F_FSDIRMASK	(int)0x70000000	/* mask for IN/OUT/VOID */
240 #define	F_FSPRIV	(int)0x00008000	/* command is fs-specific */
241 
242 /*
243  * Define command macros for operations which, if implemented, must be
244  * the same for all fs's.
245  */
246 #define	_FCN(inout, num, len) \
247 		(F_FSCTL | inout | ((len & F_PARAM_MASK) << 16) | (num))
248 #define	_FCNO(c)	_FCN(F_FSVOID,	(c), 0)
249 #define	_FCNR(c, t)	_FCN(F_FSIN,	(c), (int)sizeof(t))
250 #define	_FCNW(c, t)	_FCN(F_FSOUT,	(c), (int)sizeof(t))
251 #define	_FCNRW(c, t)	_FCN(F_FSINOUT,	(c), (int)sizeof(t))
252 
253 /*
254  * Define command macros for fs-specific commands.
255  */
256 #define	_FCN_FSPRIV(inout, fs, num, len) \
257 	(F_FSCTL | F_FSPRIV | inout | ((len & F_PARAM_MASK) << 16) |	\
258 	 (fs) << 8 | (num))
259 #define	_FCNO_FSPRIV(f, c)	_FCN_FSPRIV(F_FSVOID,  (f), (c), 0)
260 #define	_FCNR_FSPRIV(f, c, t)	_FCN_FSPRIV(F_FSIN,    (f), (c), (int)sizeof(t))
261 #define	_FCNW_FSPRIV(f, c, t)	_FCN_FSPRIV(F_FSOUT,   (f), (c), (int)sizeof(t))
262 #define	_FCNRW_FSPRIV(f, c, t)	_FCN_FSPRIV(F_FSINOUT, (f), (c), (int)sizeof(t))
263 
264 #endif /* _NETBSD_SOURCE */
265 
266 /*
267  * Advisory file segment locking data type -
268  * information passed to system by user
269  */
270 struct flock {
271 	off_t	l_start;	/* starting offset */
272 	off_t	l_len;		/* len = 0 means until end of file */
273 	pid_t	l_pid;		/* lock owner */
274 	short	l_type;		/* lock type: read/write, etc. */
275 	short	l_whence;	/* type of l_start */
276 };
277 
278 
279 #if defined(_NETBSD_SOURCE)
280 /* lock operations for flock(2) */
281 #define	LOCK_SH		0x01		/* shared file lock */
282 #define	LOCK_EX		0x02		/* exclusive file lock */
283 #define	LOCK_NB		0x04		/* don't block when locking */
284 #define	LOCK_UN		0x08		/* unlock file */
285 #endif
286 
287 /* Always ensure that these are consistent with <stdio.h> and <unistd.h>! */
288 #ifndef	SEEK_SET
289 #define	SEEK_SET	0	/* set file offset to offset */
290 #endif
291 #ifndef	SEEK_CUR
292 #define	SEEK_CUR	1	/* set file offset to current plus offset */
293 #endif
294 #ifndef	SEEK_END
295 #define	SEEK_END	2	/* set file offset to EOF plus offset */
296 #endif
297 
298 /*
299  * posix_advise advisories.
300  */
301 
302 #define	POSIX_FADV_NORMAL	0	/* default advice / no advice */
303 #define	POSIX_FADV_RANDOM	1	/* random access */
304 #define	POSIX_FADV_SEQUENTIAL	2	/* sequential access(lower to higher) */
305 #define	POSIX_FADV_WILLNEED	3	/* be needed in near future */
306 #define	POSIX_FADV_DONTNEED	4	/* not be needed in near future */
307 #define	POSIX_FADV_NOREUSE	5	/* be accessed once */
308 
309 /*
310  * Constants for X/Open Extended API set 2 (a.k.a. C063)
311  */
312 #if (_POSIX_C_SOURCE - 0) >= 200809L || (_XOPEN_SOURCE - 0 >= 700) || \
313     defined(_NETBSD_SOURCE)
314 #define	AT_FDCWD		-100	/* Use cwd for relative link target */
315 #define	AT_EACCESS		0x100	/* Use euig/egid for access checks */
316 #define	AT_SYMLINK_NOFOLLOW	0x200	/* Do not follow symlinks */
317 #define	AT_SYMLINK_FOLLOW	0x400	/* Follow symlinks */
318 #define	AT_REMOVEDIR		0x800	/* Remove directory only */
319 #endif
320 
321 
322 #ifndef _KERNEL
323 #include <sys/cdefs.h>
324 
325 __BEGIN_DECLS
326 int	open(const char *, int, ...);
327 int	creat(const char *, mode_t);
328 int	fcntl(int, int, ...);
329 #if defined(_NETBSD_SOURCE)
330 int	flock(int, int);
331 #endif /* _NETBSD_SOURCE */
332 int	posix_fadvise(int, off_t, off_t, int);
333 
334 /*
335  * The Open Group Base Specifications, Issue 6; IEEE Std 1003.1-2001 (POSIX)
336  */
337 #if (_POSIX_C_SOURCE - 0) >= 200112L || (_XOPEN_SOURCE - 0) >= 600 || \
338     defined(_NETBSD_SOURCE)
339 int	 posix_fallocate(int, off_t, off_t);
340 #endif
341 
342 /*
343  * X/Open Extended API set 2 (a.k.a. C063)
344  */
345 #if (_POSIX_C_SOURCE - 0) >= 200809L || (_XOPEN_SOURCE - 0 >= 700) || \
346     defined(_NETBSD_SOURCE)
347 int	openat(int, const char *, int, ...);
348 #endif
349 
350 __END_DECLS
351 #endif /* !_KERNEL */
352 
353 #endif /* !_SYS_FCNTL_H_ */
354