1 /*- 2 * Copyright (c) 1992, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the University nor the names of its contributors 14 * may be used to endorse or promote products derived from this software 15 * without specific prior written permission. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * @(#)select.h 8.2 (Berkeley) 1/4/94 30 * $FreeBSD: src/sys/sys/select.h,v 1.6.2.1 2000/05/05 03:50:02 jlemon Exp $ 31 */ 32 33 #ifndef _SYS__FD_SET_H_ 34 #define _SYS__FD_SET_H_ 35 36 #include <sys/cdefs.h> 37 38 /* 39 * Select uses bit masks of file descriptors in longs. These macros 40 * manipulate such bit fields (the filesystem macros use chars). 41 * FD_SETSIZE may be defined by the user, but the default here should 42 * be enough for most uses. 43 */ 44 #ifndef FD_SETSIZE 45 #define FD_SETSIZE 1024 46 #endif 47 48 #define __NBBY 8 /* number of bits in a byte */ 49 50 typedef unsigned long __fd_mask; 51 #define __NFDBITS ((unsigned int)sizeof(__fd_mask) * __NBBY) /* bits per mask */ 52 53 #ifndef __howmany 54 #define __howmany(x, y) (((x) + ((y) - 1)) / (y)) 55 #endif 56 57 typedef struct fd_set { 58 __fd_mask fds_bits[__howmany(FD_SETSIZE, __NFDBITS)]; 59 } fd_set; 60 61 #define _fdset_mask(n) ((__fd_mask)1 << ((n) % __NFDBITS)) 62 #define FD_SET(n, p) ((p)->fds_bits[(n)/__NFDBITS] |= _fdset_mask(n)) 63 #define FD_CLR(n, p) ((p)->fds_bits[(n)/__NFDBITS] &= ~_fdset_mask(n)) 64 #define FD_ISSET(n, p) ((p)->fds_bits[(n)/__NFDBITS] & _fdset_mask(n)) 65 #define FD_ZERO(p) __builtin_memset((p), 0, sizeof(*(p))) 66 67 68 /* 69 * Expose classic BSD names if we're not running in conformance mode. 70 */ 71 #if __BSD_VISIBLE 72 73 #define fd_mask __fd_mask 74 #define NFDBITS __NFDBITS 75 #ifndef howmany 76 #define howmany(a, b) __howmany(a, b) 77 #endif 78 79 #define FD_COPY(f, t) __builtin_memcpy((t), (f), sizeof(*(f))) 80 81 #endif /* __BSD_VISIBLE */ 82 83 #endif /* _SYS__FD_SET_H_ */ 84