xref: /freebsd/sys/sys/poll.h (revision 16038816)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1997 Peter Wemm <peter@freebsd.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * $FreeBSD$
31  */
32 
33 #ifndef _SYS_POLL_H_
34 #define	_SYS_POLL_H_
35 
36 #include <sys/cdefs.h>
37 
38 /*
39  * This file is intended to be compatible with the traditional poll.h.
40  */
41 
42 typedef	unsigned int	nfds_t;
43 
44 /*
45  * This structure is passed as an array to poll(2).
46  */
47 struct pollfd {
48 	int	fd;		/* which file descriptor to poll */
49 	short	events;		/* events we are interested in */
50 	short	revents;	/* events found on return */
51 };
52 
53 /*
54  * Requestable events.  If poll(2) finds any of these set, they are
55  * copied to revents on return.
56  * XXX Note that FreeBSD doesn't make much distinction between POLLPRI
57  * and POLLRDBAND since none of the file types have distinct priority
58  * bands - and only some have an urgent "mode".
59  * XXX Note POLLIN isn't really supported in true SVSV terms.  Under SYSV
60  * POLLIN includes all of normal, band and urgent data.  Most poll handlers
61  * on FreeBSD only treat it as "normal" data.
62  */
63 #define	POLLIN		0x0001		/* any readable data available */
64 #define	POLLPRI		0x0002		/* OOB/Urgent readable data */
65 #define	POLLOUT		0x0004		/* file descriptor is writeable */
66 #define	POLLRDNORM	0x0040		/* non-OOB/URG data available */
67 #define	POLLWRNORM	POLLOUT		/* no write type differentiation */
68 #define	POLLRDBAND	0x0080		/* OOB/Urgent readable data */
69 #define	POLLWRBAND	0x0100		/* OOB/Urgent data can be written */
70 
71 #if __BSD_VISIBLE
72 /* General FreeBSD extension (currently only supported for sockets): */
73 #define	POLLINIGNEOF	0x2000		/* like POLLIN, except ignore EOF */
74 #define	POLLRDHUP	0x4000		/* half shut down */
75 #endif
76 
77 /*
78  * These events are set if they occur regardless of whether they were
79  * requested.
80  */
81 #define	POLLERR		0x0008		/* some poll error occurred */
82 #define	POLLHUP		0x0010		/* file descriptor was "hung up" */
83 #define	POLLNVAL	0x0020		/* requested events "invalid" */
84 
85 #if __BSD_VISIBLE
86 
87 #define	POLLSTANDARD	(POLLIN|POLLPRI|POLLOUT|POLLRDNORM|POLLRDBAND|\
88 			 POLLWRBAND|POLLERR|POLLHUP|POLLNVAL)
89 
90 /*
91  * Request that poll() wait forever.
92  * XXX in SYSV, this is defined in stropts.h, which is not included
93  * by poll.h.
94  */
95 #define	INFTIM		(-1)
96 
97 #endif
98 
99 #ifndef _KERNEL
100 
101 #if __BSD_VISIBLE
102 #include <sys/_types.h>
103 
104 #include <sys/_sigset.h>
105 #include <sys/timespec.h>
106 
107 #ifndef _SIGSET_T_DECLARED
108 #define	_SIGSET_T_DECLARED
109 typedef	__sigset_t	sigset_t;
110 #endif
111 
112 #endif
113 
114 __BEGIN_DECLS
115 int	poll(struct pollfd _pfd[], nfds_t _nfds, int _timeout);
116 #if __BSD_VISIBLE
117 int	ppoll(struct pollfd _pfd[], nfds_t _nfds,
118 	    const struct timespec *__restrict _timeout,
119 	    const sigset_t *__restrict _newsigmask);
120 #endif
121 __END_DECLS
122 
123 #endif /* !_KERNEL */
124 
125 #endif /* !_SYS_POLL_H_ */
126