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/*
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 * Copyright (c) 1989, 1993
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 *	The Regents of the University of California.  All rights reserved.
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 *
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 * This code is derived from software contributed to Berkeley by
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 * Paul Vixie.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. All advertising materials mentioning features or use of this software
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 *    must display the following acknowledgement:
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 *	This product includes software developed by the University of
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 *	California, Berkeley and its contributors.
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 * 4. Neither the name of the University nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 *
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 *	@(#)bitstring.h	8.1 (Berkeley) 7/19/93
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 */
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#ifndef _BITSTRING_H_
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#define	_BITSTRING_H_
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typedef	unsigned char bitstr_t;
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/* internal macros */
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				/* byte of the bitstring bit is in */
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#define	_bit_byte(bit) \
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	((bit) >> 3)
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				/* mask for the bit within its byte */
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#define	_bit_mask(bit) \
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	(1 << ((bit)&0x7))
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/* external macros */
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				/* bytes in a bitstring of nbits bits */
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#define	bitstr_size(nbits) \
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	((((nbits) - 1) >> 3) + 1)
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				/* allocate a bitstring */
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#define	bit_alloc(space, nbits, type, flags) \
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	MALLOC((space), bitstr_t *, \
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        (u_int)bitstr_size(nbits)*sizeof(bitstr_t), (type), (flags))
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				/* allocate a bitstring on the stack */
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#define	bit_decl(name, nbits) \
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	(name)[bitstr_size(nbits)]
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				/* is bit N of bitstring name set? */
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#define	bit_test(name, bit) \
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	((name)[_bit_byte(bit)] & _bit_mask(bit))
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				/* set bit N of bitstring name */
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#define	bit_set(name, bit) \
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	(name)[_bit_byte(bit)] |= _bit_mask(bit)
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				/* clear bit N of bitstring name */
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#define	bit_clear(name, bit) \
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	(name)[_bit_byte(bit)] &= ~_bit_mask(bit)
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				/* clear bits start ... stop in bitstring */
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#define	bit_nclear(name, start, stop) { \
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	register bitstr_t *_name = name; \
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	register int _start = start, _stop = stop; \
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	register int _startbyte = _bit_byte(_start); \
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	register int _stopbyte = _bit_byte(_stop); \
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	if (_startbyte == _stopbyte) { \
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		_name[_startbyte] &= ((0xff >> (8 - (_start&0x7))) | \
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				      (0xff << ((_stop&0x7) + 1))); \
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	} else { \
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		_name[_startbyte] &= 0xff >> (8 - (_start&0x7)); \
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		while (++_startbyte < _stopbyte) \
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			_name[_startbyte] = 0; \
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		_name[_stopbyte] &= 0xff << ((_stop&0x7) + 1); \
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	} \
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}
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				/* set bits start ... stop in bitstring */
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#define	bit_nset(name, start, stop) { \
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	register bitstr_t *_name = name; \
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	register int _start = start, _stop = stop; \
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	register int _startbyte = _bit_byte(_start); \
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	register int _stopbyte = _bit_byte(_stop); \
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	if (_startbyte == _stopbyte) { \
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		_name[_startbyte] |= ((0xff << (_start&0x7)) & \
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				    (0xff >> (7 - (_stop&0x7)))); \
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	} else { \
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		_name[_startbyte] |= 0xff << ((_start)&0x7); \
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		while (++_startbyte < _stopbyte) \
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	    		_name[_startbyte] = 0xff; \
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		_name[_stopbyte] |= 0xff >> (7 - (_stop&0x7)); \
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	} \
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}
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				/* find first bit clear in name */
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#define	bit_ffc(name, nbits, value) { \
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	register bitstr_t *_name = name; \
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	register int _byte, _nbits = nbits; \
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	register int _stopbyte = _bit_byte(_nbits), _value = -1; \
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	for (_byte = 0; _byte <= _stopbyte; ++_byte) \
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		if (_name[_byte] != 0xff) { \
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			_value = _byte << 3; \
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			for (_stopbyte = _name[_byte]; (_stopbyte&0x1); \
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			    ++_value, _stopbyte >>= 1); \
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			break; \
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		} \
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	*(value) = _value; \
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}
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				/* find first bit set in name */
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#define	bit_ffs(name, nbits, value) { \
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	register bitstr_t *_name = name; \
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	register int _byte, _nbits = nbits; \
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	register int _stopbyte = _bit_byte(_nbits), _value = -1; \
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	for (_byte = 0; _byte <= _stopbyte; ++_byte) \
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		if (_name[_byte]) { \
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			_value = _byte << 3; \
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			for (_stopbyte = _name[_byte]; !(_stopbyte&0x1); \
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			    ++_value, _stopbyte >>= 1); \
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			break; \
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		} \
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	*(value) = _value; \
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}
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#endif /* !_BITSTRING_H_ */