1/* $OpenBSD: bitstring.h,v 1.6 2020/05/10 00:56:06 guenther Exp $ */ 2/* $NetBSD: bitstring.h,v 1.5 1997/05/14 15:49:55 pk Exp $ */ 3 4/* 5 * Copyright (c) 1989, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * Paul Vixie. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)bitstring.h 8.1 (Berkeley) 7/19/93 36 */ 37 38#ifndef _BITSTRING_H_ 39#define _BITSTRING_H_ 40 41/* modified for SV/AT and bitstring bugfix by M.R.Murphy, 11oct91 42 * bitstr_size changed gratuitously, but shorter 43 * bit_alloc spelling error fixed 44 * the following were efficient, but didn't work, they've been made to 45 * work, but are no longer as efficient :-) 46 * bit_nclear, bit_nset, bit_ffc, bit_ffs 47 */ 48typedef unsigned char bitstr_t; 49 50/* internal macros */ 51 /* byte of the bitstring bit is in */ 52#define _bit_byte(bit) \ 53 ((bit) >> 3) 54 55 /* mask for the bit within its byte */ 56#define _bit_mask(bit) \ 57 (1 << ((bit)&0x7)) 58 59/* external macros */ 60 /* bytes in a bitstring of nbits bits */ 61#define bitstr_size(nbits) \ 62 (((nbits) + 7) >> 3) 63 64 /* allocate a bitstring */ 65#define bit_alloc(nbits) \ 66 (bitstr_t *)calloc((size_t)bitstr_size(nbits), sizeof(bitstr_t)) 67 68 /* allocate a bitstring on the stack */ 69#define bit_decl(name, nbits) \ 70 ((name)[bitstr_size(nbits)]) 71 72 /* is bit N of bitstring name set? */ 73#define bit_test(name, bit) \ 74 ((name)[_bit_byte(bit)] & _bit_mask(bit)) 75 76 /* set bit N of bitstring name */ 77#define bit_set(name, bit) \ 78 ((name)[_bit_byte(bit)] |= _bit_mask(bit)) 79 80 /* clear bit N of bitstring name */ 81#define bit_clear(name, bit) \ 82 ((name)[_bit_byte(bit)] &= ~_bit_mask(bit)) 83 84 /* clear bits start ... stop in bitstring */ 85#define bit_nclear(name, start, stop) do { \ 86 register bitstr_t *__name = (name); \ 87 register int __start = (start), __stop = (stop); \ 88 while (__start <= __stop) { \ 89 bit_clear(__name, __start); \ 90 __start++; \ 91 } \ 92} while(0) 93 94 /* set bits start ... stop in bitstring */ 95#define bit_nset(name, start, stop) do { \ 96 register bitstr_t *__name = (name); \ 97 register int __start = (start), __stop = (stop); \ 98 while (__start <= __stop) { \ 99 bit_set(__name, __start); \ 100 __start++; \ 101 } \ 102} while(0) 103 104 /* find first bit clear in name */ 105#define bit_ffc(name, nbits, value) do { \ 106 register bitstr_t *__name = (name); \ 107 register int __bit, __nbits = (nbits), __value = -1; \ 108 for (__bit = 0; __bit < __nbits; ++__bit) \ 109 if (!bit_test(__name, __bit)) { \ 110 __value = __bit; \ 111 break; \ 112 } \ 113 *(value) = __value; \ 114} while(0) 115 116 /* find first bit set in name */ 117#define bit_ffs(name, nbits, value) do { \ 118 register bitstr_t *__name = (name); \ 119 register int __bit, __nbits = (nbits), __value = -1; \ 120 for (__bit = 0; __bit < __nbits; ++__bit) \ 121 if (bit_test(__name, __bit)) { \ 122 __value = __bit; \ 123 break; \ 124 } \ 125 *(value) = __value; \ 126} while(0) 127 128#endif /* !_BITSTRING_H_ */ 129