ref: 097aa39101e6ac679b3a155ccfd1e5b85b823eac
dir: /sys/src/cmd/python/Include/bitset.h/
#ifndef Py_BITSET_H
#define Py_BITSET_H
#ifdef __cplusplus
extern "C" {
#endif
/* Bitset interface */
#define BYTE		char
typedef BYTE *bitset;
bitset newbitset(int nbits);
void delbitset(bitset bs);
#define testbit(ss, ibit) (((ss)[BIT2BYTE(ibit)] & BIT2MASK(ibit)) != 0)
int addbit(bitset bs, int ibit); /* Returns 0 if already set */
int samebitset(bitset bs1, bitset bs2, int nbits);
void mergebitset(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)
#ifdef __cplusplus
}
#endif
#endif /* !Py_BITSET_H */