Skip to content
This repository

HTTPS clone URL

Subversion checkout URL

You can clone with HTTPS or Subversion.

Download ZIP
branch: netbsd_1_3
Fetching contributors…

Cannot retrieve contributors at this time

file 115 lines (99 sloc) 3.48 kb
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115
/* $NetBSD: bitstring.h,v 1.5 1997/05/14 15:49:55 pk Exp $ */

/*
* Copyright (c) 1989 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Paul Vixie.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* @(#)bitstring.h 5.2 (Berkeley) 4/4/90
*/

#ifndef _BITSTRING_H_
#define _BITSTRING_H_

/* modified for SV/AT and bitstring bugfix by M.R.Murphy, 11oct91
* bitstr_size changed gratuitously, but shorter
* bit_alloc spelling error fixed
* the following were efficient, but didn't work, they've been made to
* work, but are no longer as efficient :-)
* bit_nclear, bit_nset, bit_ffc, bit_ffs
*/
typedef unsigned char bitstr_t;

/* internal macros */
/* byte of the bitstring bit is in */
#define _bit_byte(bit) \
((bit) >> 3)

/* mask for the bit within its byte */
#define _bit_mask(bit) \
(1 << ((bit)&0x7))

/* external macros */
/* bytes in a bitstring of nbits bits */
#define bitstr_size(nbits) \
(((nbits) + 7) >> 3)

/* allocate a bitstring */
#define bit_alloc(nbits) \
(bitstr_t *)calloc((size_t)bitstr_size(nbits), sizeof(bitstr_t))

/* allocate a bitstring on the stack */
#define bit_decl(name, nbits) \
((name)[bitstr_size(nbits)])

/* is bit N of bitstring name set? */
#define bit_test(name, bit) \
((name)[_bit_byte(bit)] & _bit_mask(bit))

/* set bit N of bitstring name */
#define bit_set(name, bit) \
((name)[_bit_byte(bit)] |= _bit_mask(bit))

/* clear bit N of bitstring name */
#define bit_clear(name, bit) \
((name)[_bit_byte(bit)] &= ~_bit_mask(bit))

/* clear bits start ... stop in bitstring */
#define bit_nclear(name, start, stop) do { \
register bitstr_t *_name = name; \
register int _start = start, _stop = stop; \
while (_start <= _stop) { \
bit_clear(_name, _start); \
_start++; \
} \
} while(0)

/* set bits start ... stop in bitstring */
#define bit_nset(name, start, stop) do { \
register bitstr_t *_name = name; \
register int _start = start, _stop = stop; \
while (_start <= _stop) { \
bit_set(_name, _start); \
_start++; \
} \
} while(0)

/* find first bit clear in name */
#define bit_ffc(name, nbits, value) do { \
register bitstr_t *_name = name; \
register int _bit, _nbits = nbits, _value = -1; \
for (_bit = 0; _bit < _nbits; ++_bit) \
if (!bit_test(_name, _bit)) { \
_value = _bit; \
break; \
} \
*(value) = _value; \
} while(0)

/* find first bit set in name */
#define bit_ffs(name, nbits, value) do { \
register bitstr_t *_name = name; \
register int _bit, _nbits = nbits, _value = -1; \
for (_bit = 0; _bit < _nbits; ++_bit) \
if (bit_test(_name, _bit)) { \
_value = _bit; \
break; \
} \
*(value) = _value; \
} while(0)

#endif /* !_BITSTRING_H_ */
Something went wrong with that request. Please try again.