1 /* $OpenBSD: select.h,v 1.9 2006/03/21 08:17:33 otto Exp $ */
2
3 /*-
4 * Copyright (c) 1992, 1993
5 * The Regents of the University of California. 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. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * @(#)select.h 8.2 (Berkeley) 1/4/94
32 */
33
34 #ifndef _SYS_SELECT_H_
35 #define _SYS_SELECT_H_
36
37 #include <sys/cdefs.h>
38 #include <sys/time.h> /* for types and struct timeval */
39
40 /*
41 * Select uses bit masks of file descriptors in longs. These macros
42 * manipulate such bit fields (the filesystem macros use chars).
43 * FD_SETSIZE may be defined by the user, but the default here should
44 * be enough for most uses.
45 */
46 #ifndef FD_SETSIZE
47 #define FD_SETSIZE 1024
48 #endif
49
50 /*
51 * We don't want to pollute the namespace with select(2) internals.
52 * Non-underscore versions are exposed later #if __BSD_VISIBLE
53 */
54 #define __NBBY 8 /* number of bits in a byte */
55 typedef int32_t __fd_mask;
56 #define __NFDBITS ((unsigned)(sizeof(__fd_mask) * __NBBY)) /* bits per mask */
57 #define __howmany(x, y) (((x) + ((y) - 1)) / (y))
58
59 typedef struct fd_set {
60 __fd_mask fds_bits[__howmany(FD_SETSIZE, __NFDBITS)];
61 } fd_set;
62
63 #define FD_SET(n, p) \
64 ((p)->fds_bits[(n) / __NFDBITS] |= (1 << ((n) % __NFDBITS)))
65 #define FD_CLR(n, p) \
66 ((p)->fds_bits[(n) / __NFDBITS] &= ~(1 << ((n) % __NFDBITS)))
67 #define FD_ISSET(n, p) \
68 ((p)->fds_bits[(n) / __NFDBITS] & (1 << ((n) % __NFDBITS)))
69 #ifdef _KERNEL
70 #define FD_COPY(f, t) bcopy(f, t, sizeof(*(f)))
71 #define FD_ZERO(p) bzero(p, sizeof(*(p)))
72 #else
73 #define FD_COPY(f, t) memcpy(t, f, sizeof(*(f)))
74 #define FD_ZERO(p) memset(p, 0, sizeof(*(p)))
75 #endif
76
77 #if __BSD_VISIBLE
78 #define NBBY __NBBY
79 #define fd_mask __fd_mask
80 #define NFDBITS __NFDBITS
81 #ifndef howmany
82 #define howmany(x, y) __howmany(x, y)
83 #endif
84 #endif /* __BSD_VISIBLE */
85
86 #ifndef _KERNEL
87 #ifndef _SELECT_DEFINED_
88 #define _SELECT_DEFINED_
89 __BEGIN_DECLS
90 struct timeval;
91 int select(int, fd_set *, fd_set *, fd_set *, struct timeval *);
92 __END_DECLS
93 #endif
94 #endif /* !_KERNEL */
95
96 #endif /* !_SYS_SELECT_H_ */