c3-lang/libbsd/include/bsd/sys/bitstring.h

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• Hash : ec5d9a68
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  Date : 2017-06-14T02:44:37
  

  Namespace header inclusion protection macros Use LIBBSD_, and remove trailing underscores.

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• include/bsd/sys/bitstring.h

• /*-
   * Copyright (c) 1989, 1993
   *	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, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   * 4. Neither the name of the University nor the names of its contributors
   *    may be used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   *
   * $FreeBSD$
   */
  
  #ifndef LIBBSD_SYS_BITSTRING_H
  #define LIBBSD_SYS_BITSTRING_H
  
  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); \
  	register int _startbyte = _bit_byte(_start); \
  	register int _stopbyte = _bit_byte(_stop); \
  	if (_startbyte == _stopbyte) { \
  		_name[_startbyte] &= ((0xff >> (8 - (_start&0x7))) | \
  				      (0xff << ((_stop&0x7) + 1))); \
  	} else { \
  		_name[_startbyte] &= 0xff >> (8 - (_start&0x7)); \
  		while (++_startbyte < _stopbyte) \
  			_name[_startbyte] = 0; \
  		_name[_stopbyte] &= 0xff << ((_stop&0x7) + 1); \
  	} \
  } 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); \
  	register int _startbyte = _bit_byte(_start); \
  	register int _stopbyte = _bit_byte(_stop); \
  	if (_startbyte == _stopbyte) { \
  		_name[_startbyte] |= ((0xff << (_start&0x7)) & \
  				    (0xff >> (7 - (_stop&0x7)))); \
  	} else { \
  		_name[_startbyte] |= 0xff << ((_start)&0x7); \
  		while (++_startbyte < _stopbyte) \
  	    		_name[_startbyte] = 0xff; \
  		_name[_stopbyte] |= 0xff >> (7 - (_stop&0x7)); \
  	} \
  } while (0)
  
  				/* find first bit clear in name */
  #define	bit_ffc(name, nbits, value) do { \
  	register bitstr_t *_name = (name); \
  	register int _byte, _nbits = (nbits); \
  	register int _stopbyte = _bit_byte(_nbits - 1), _value = -1; \
  	if (_nbits > 0) \
  		for (_byte = 0; _byte <= _stopbyte; ++_byte) \
  			if (_name[_byte] != 0xff) { \
  				bitstr_t _lb; \
  				_value = _byte << 3; \
  				for (_lb = _name[_byte]; (_lb&0x1); \
  				    ++_value, _lb >>= 1); \
  				break; \
  			} \
  	if (_value >= nbits) \
  		_value = -1; \
  	*(value) = _value; \
  } while (0)
  
  				/* find first bit set in name */
  #define	bit_ffs(name, nbits, value) do { \
  	register bitstr_t *_name = (name); \
  	register int _byte, _nbits = (nbits); \
  	register int _stopbyte = _bit_byte(_nbits - 1), _value = -1; \
  	if (_nbits > 0) \
  		for (_byte = 0; _byte <= _stopbyte; ++_byte) \
  			if (_name[_byte]) { \
  				bitstr_t _lb; \
  				_value = _byte << 3; \
  				for (_lb = _name[_byte]; !(_lb&0x1); \
  				    ++_value, _lb >>= 1); \
  				break; \
  			} \
  	if (_value >= nbits) \
  		_value = -1; \
  	*(value) = _value; \
  } while (0)
  
  #endif /* !LIBBSD_SYS_BITSTRING_H */
  

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