bitstring.h revision 1.1.2.3
1 1.1.2.2 yamt /*- 2 1.1.2.2 yamt * Copyright (c) 1989, 1993 3 1.1.2.2 yamt * The Regents of the University of California. All rights reserved. 4 1.1.2.2 yamt * 5 1.1.2.2 yamt * This code is derived from software contributed to Berkeley by 6 1.1.2.2 yamt * Paul Vixie. 7 1.1.2.2 yamt * 8 1.1.2.2 yamt * Redistribution and use in source and binary forms, with or without 9 1.1.2.2 yamt * modification, are permitted provided that the following conditions 10 1.1.2.2 yamt * are met: 11 1.1.2.2 yamt * 1. Redistributions of source code must retain the above copyright 12 1.1.2.2 yamt * notice, this list of conditions and the following disclaimer. 13 1.1.2.2 yamt * 2. Redistributions in binary form must reproduce the above copyright 14 1.1.2.2 yamt * notice, this list of conditions and the following disclaimer in the 15 1.1.2.2 yamt * documentation and/or other materials provided with the distribution. 16 1.1.2.2 yamt * 4. Neither the name of the University nor the names of its contributors 17 1.1.2.2 yamt * may be used to endorse or promote products derived from this software 18 1.1.2.2 yamt * without specific prior written permission. 19 1.1.2.2 yamt * 20 1.1.2.2 yamt * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 1.1.2.2 yamt * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 1.1.2.2 yamt * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 1.1.2.2 yamt * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 1.1.2.2 yamt * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 1.1.2.2 yamt * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 1.1.2.2 yamt * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 1.1.2.2 yamt * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 1.1.2.2 yamt * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 1.1.2.2 yamt * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 1.1.2.2 yamt * SUCH DAMAGE. 31 1.1.2.2 yamt * 32 1.1.2.3 yamt * $FreeBSD: src/sys/sys/bitstring.h,v 1.4 2004/04/07 04:19:48 imp Exp $ 33 1.1.2.2 yamt */ 34 1.1.2.2 yamt 35 1.1.2.2 yamt #ifndef _SYS_BITSTRING_H_ 36 1.1.2.2 yamt #define _SYS_BITSTRING_H_ 37 1.1.2.2 yamt 38 1.1.2.2 yamt typedef unsigned char bitstr_t; 39 1.1.2.2 yamt 40 1.1.2.2 yamt /* internal macros */ 41 1.1.2.2 yamt /* byte of the bitstring bit is in */ 42 1.1.2.2 yamt #define _bit_byte(bit) \ 43 1.1.2.2 yamt ((bit) >> 3) 44 1.1.2.2 yamt 45 1.1.2.2 yamt /* mask for the bit within its byte */ 46 1.1.2.2 yamt #define _bit_mask(bit) \ 47 1.1.2.2 yamt (1 << ((bit)&0x7)) 48 1.1.2.2 yamt 49 1.1.2.2 yamt /* external macros */ 50 1.1.2.2 yamt /* bytes in a bitstring of nbits bits */ 51 1.1.2.2 yamt #define bitstr_size(nbits) \ 52 1.1.2.2 yamt (((nbits) + 7) >> 3) 53 1.1.2.2 yamt 54 1.1.2.2 yamt /* allocate a bitstring */ 55 1.1.2.2 yamt #define bit_alloc(nbits) \ 56 1.1.2.2 yamt (bitstr_t *)calloc((size_t)bitstr_size(nbits), sizeof(bitstr_t)) 57 1.1.2.2 yamt 58 1.1.2.2 yamt /* allocate a bitstring on the stack */ 59 1.1.2.2 yamt #define bit_decl(name, nbits) \ 60 1.1.2.2 yamt ((name)[bitstr_size(nbits)]) 61 1.1.2.2 yamt 62 1.1.2.2 yamt /* is bit N of bitstring name set? */ 63 1.1.2.2 yamt #define bit_test(name, bit) \ 64 1.1.2.2 yamt ((name)[_bit_byte(bit)] & _bit_mask(bit)) 65 1.1.2.2 yamt 66 1.1.2.2 yamt /* set bit N of bitstring name */ 67 1.1.2.2 yamt #define bit_set(name, bit) \ 68 1.1.2.2 yamt ((name)[_bit_byte(bit)] |= _bit_mask(bit)) 69 1.1.2.2 yamt 70 1.1.2.2 yamt /* clear bit N of bitstring name */ 71 1.1.2.2 yamt #define bit_clear(name, bit) \ 72 1.1.2.2 yamt ((name)[_bit_byte(bit)] &= ~_bit_mask(bit)) 73 1.1.2.2 yamt 74 1.1.2.2 yamt /* clear bits start ... stop in bitstring */ 75 1.1.2.2 yamt #define bit_nclear(name, start, stop) do { \ 76 1.1.2.2 yamt register bitstr_t *_name = (name); \ 77 1.1.2.2 yamt register int _start = (start), _stop = (stop); \ 78 1.1.2.2 yamt register int _startbyte = _bit_byte(_start); \ 79 1.1.2.2 yamt register int _stopbyte = _bit_byte(_stop); \ 80 1.1.2.2 yamt if (_startbyte == _stopbyte) { \ 81 1.1.2.2 yamt _name[_startbyte] &= ((0xff >> (8 - (_start&0x7))) | \ 82 1.1.2.2 yamt (0xff << ((_stop&0x7) + 1))); \ 83 1.1.2.2 yamt } else { \ 84 1.1.2.2 yamt _name[_startbyte] &= 0xff >> (8 - (_start&0x7)); \ 85 1.1.2.2 yamt while (++_startbyte < _stopbyte) \ 86 1.1.2.2 yamt _name[_startbyte] = 0; \ 87 1.1.2.2 yamt _name[_stopbyte] &= 0xff << ((_stop&0x7) + 1); \ 88 1.1.2.2 yamt } \ 89 1.1.2.2 yamt } while (0) 90 1.1.2.2 yamt 91 1.1.2.2 yamt /* set bits start ... stop in bitstring */ 92 1.1.2.2 yamt #define bit_nset(name, start, stop) do { \ 93 1.1.2.2 yamt register bitstr_t *_name = (name); \ 94 1.1.2.2 yamt register int _start = (start), _stop = (stop); \ 95 1.1.2.2 yamt register int _startbyte = _bit_byte(_start); \ 96 1.1.2.2 yamt register int _stopbyte = _bit_byte(_stop); \ 97 1.1.2.2 yamt if (_startbyte == _stopbyte) { \ 98 1.1.2.2 yamt _name[_startbyte] |= ((0xff << (_start&0x7)) & \ 99 1.1.2.2 yamt (0xff >> (7 - (_stop&0x7)))); \ 100 1.1.2.2 yamt } else { \ 101 1.1.2.2 yamt _name[_startbyte] |= 0xff << ((_start)&0x7); \ 102 1.1.2.2 yamt while (++_startbyte < _stopbyte) \ 103 1.1.2.2 yamt _name[_startbyte] = 0xff; \ 104 1.1.2.2 yamt _name[_stopbyte] |= 0xff >> (7 - (_stop&0x7)); \ 105 1.1.2.2 yamt } \ 106 1.1.2.2 yamt } while (0) 107 1.1.2.2 yamt 108 1.1.2.2 yamt /* find first bit clear in name */ 109 1.1.2.2 yamt #define bit_ffc(name, nbits, value) do { \ 110 1.1.2.2 yamt register bitstr_t *_name = (name); \ 111 1.1.2.2 yamt register int _byte, _nbits = (nbits); \ 112 1.1.2.2 yamt register int _stopbyte = _bit_byte(_nbits - 1), _value = -1; \ 113 1.1.2.2 yamt if (_nbits > 0) \ 114 1.1.2.2 yamt for (_byte = 0; _byte <= _stopbyte; ++_byte) \ 115 1.1.2.2 yamt if (_name[_byte] != 0xff) { \ 116 1.1.2.2 yamt bitstr_t _lb; \ 117 1.1.2.2 yamt _value = _byte << 3; \ 118 1.1.2.2 yamt for (_lb = _name[_byte]; (_lb&0x1); \ 119 1.1.2.2 yamt ++_value, _lb >>= 1); \ 120 1.1.2.2 yamt break; \ 121 1.1.2.2 yamt } \ 122 1.1.2.2 yamt if (_value >= nbits) \ 123 1.1.2.2 yamt _value = -1; \ 124 1.1.2.2 yamt *(value) = _value; \ 125 1.1.2.2 yamt } while (0) 126 1.1.2.2 yamt 127 1.1.2.2 yamt /* find first bit set in name */ 128 1.1.2.2 yamt #define bit_ffs(name, nbits, value) do { \ 129 1.1.2.2 yamt register bitstr_t *_name = (name); \ 130 1.1.2.2 yamt register int _byte, _nbits = (nbits); \ 131 1.1.2.2 yamt register int _stopbyte = _bit_byte(_nbits - 1), _value = -1; \ 132 1.1.2.2 yamt if (_nbits > 0) \ 133 1.1.2.2 yamt for (_byte = 0; _byte <= _stopbyte; ++_byte) \ 134 1.1.2.2 yamt if (_name[_byte]) { \ 135 1.1.2.2 yamt bitstr_t _lb; \ 136 1.1.2.2 yamt _value = _byte << 3; \ 137 1.1.2.2 yamt for (_lb = _name[_byte]; !(_lb&0x1); \ 138 1.1.2.2 yamt ++_value, _lb >>= 1); \ 139 1.1.2.2 yamt break; \ 140 1.1.2.2 yamt } \ 141 1.1.2.2 yamt if (_value >= nbits) \ 142 1.1.2.2 yamt _value = -1; \ 143 1.1.2.2 yamt *(value) = _value; \ 144 1.1.2.2 yamt } while (0) 145 1.1.2.2 yamt 146 1.1.2.2 yamt #endif /* !_SYS_BITSTRING_H_ */ 147
Indexes created Tue Oct 07 21:09:53 GMT 2025