Include/bitset.h

/***********************************************************
Copyright 1991, 1992 by Stichting Mathematisch Centrum, Amsterdam, The
Netherlands.

                        All Rights Reserved

Permission to use, copy, modify, and distribute this software and its 
documentation for any purpose and without fee is hereby granted, 
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in 
supporting documentation, and that the names of Stichting Mathematisch
Centrum or CWI not be used in advertising or publicity pertaining to
distribution of the software without specific, written prior permission.

STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

******************************************************************/

/* Bitset interface */

#define BYTE		char

typedef BYTE *bitset;

bitset newbitset PROTO((int nbits));
void delbitset PROTO((bitset bs));
/* int testbit PROTO((bitset bs, int ibit)); /* Now a macro, see below */
int addbit PROTO((bitset bs, int ibit)); /* Returns 0 if already set */
int samebitset PROTO((bitset bs1, bitset bs2, int nbits));
void mergebitset PROTO((bitset bs1, bitset bs2, int nbits));

#define BITSPERBYTE	(8*sizeof(BYTE))
#define NBYTES(nbits)	(((nbits) + BITSPERBYTE - 1) / BITSPERBYTE)

#define BIT2BYTE(ibit)	((ibit) / BITSPERBYTE)
#define BIT2SHIFT(ibit)	((ibit) % BITSPERBYTE)
#define BIT2MASK(ibit)	(1 << BIT2SHIFT(ibit))
#define BYTE2BIT(ibyte)	((ibyte) * BITSPERBYTE)

#define testbit(ss, ibit) (((ss)[BIT2BYTE(ibit)] & BIT2MASK(ibit)) != 0)