keychain/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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 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.
 *
 *      @(#)bitstring.h 8.1 (Berkeley) 7/19/93
 */

/*
 * Adapted from BSD bitstring.h
 */

#ifndef _TPM_KEYCHAIN_BITSTRING_H_
#define _TPM_KEYCHAIN_BITSTRING_H_

typedef unsigned char bitstr_t;

#define _bit_byte(bit)        ((bit) >> 3)
#define _bit_mask(bit)        (1 << ((bit) & 0x7))
#define _bitstr_size(nbits)   ((((nbits) - 1) >> 3) + 1)

#define bit_decl(name, nbits) (name)[_bitstr_size(nbits)]
#define bit_test(name, bit)   ((name)[_bit_byte(bit)] & _bit_mask(bit))
#define bit_set(name, bit)    (name)[_bit_byte(bit)] |= _bit_mask(bit)
#define bit_clear(name, bit)  (name)[_bit_byte(bit)] &= ~_bit_mask(bit)
#define bit_nclear(name, start, stop) { \
          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); \
          } \
        }

#endif // _TPM_KEYCHAIN_BITSTRING_H_