diff options
Diffstat (limited to 'include/bitstring.h')
| -rw-r--r-- | include/bitstring.h | 59 |
1 files changed, 28 insertions, 31 deletions
diff --git a/include/bitstring.h b/include/bitstring.h index 21f10f697a15..2ed0e65e8ca2 100644 --- a/include/bitstring.h +++ b/include/bitstring.h @@ -33,12 +33,20 @@ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * - * @(#)bitstring.h 5.5 (Berkeley) 4/3/91 + * from: @(#)bitstring.h 5.5 (Berkeley) 4/3/91 + * $Id: bitstring.h,v 1.2 1994/02/17 08:54:00 rgrimes Exp $ */ #ifndef _BITSTRING_H_ -#define _BITSTRING_H_ +#define _BITSTRING_H_ +/* modified for SV/AT and bitstring bugfix by M.R.Murphy, 11oct91 + * bitstr_size changed gratuitously, but shorter + * bit_alloc spelling error fixed + * the following were efficient, but didn't work, they've been made to + * work, but are no longer as efficient :-) + * bit_nclear, bit_nset, bit_ffc, bit_ffs + */ typedef unsigned char bitstr_t; /* internal macros */ @@ -53,12 +61,11 @@ typedef unsigned char bitstr_t; /* external macros */ /* bytes in a bitstring of nbits bits */ #define bitstr_size(nbits) \ - ((((nbits) - 1) >> 3) + 1) + (((nbits) + 7) >> 3) /* allocate a bitstring */ #define bit_alloc(nbits) \ - (bitstr_t *)calloc(1, \ - (unsigned int)_bitstr_size(nbits) * sizeof(bitstr_t)) + (bitstr_t *)calloc((size_t)bitstr_size(nbits), sizeof(bitstr_t)) /* allocate a bitstring on the stack */ #define bit_decl(name, nbits) \ @@ -80,36 +87,29 @@ typedef unsigned char bitstr_t; #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); \ - _name[_startbyte] &= 0xff >> (8 - (_start&0x7)); \ - while (++_startbyte < _stopbyte) \ - _name[_startbyte] = 0; \ - _name[_stopbyte] &= 0xff << ((_stop&0x7) + 1); \ + while (_start <= _stop) { \ + bit_clear(_name, _start); \ + _start++; \ + } \ } /* set bits start ... stop in bitstring */ #define bit_nset(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); \ - _name[_startbyte] |= 0xff << ((start)&0x7); \ - while (++_startbyte < _stopbyte) \ - _name[_startbyte] = 0xff; \ - _name[_stopbyte] |= 0xff >> (7 - (_stop&0x7)); \ + while (_start <= _stop) { \ + bit_set(_name, _start); \ + _start++; \ + } \ } /* find first bit clear in name */ #define bit_ffc(name, nbits, value) { \ register bitstr_t *_name = name; \ - register int _byte, _nbits = nbits; \ - register int _stopbyte = _bit_byte(_nbits), _value = -1; \ - for (_byte = 0; _byte <= _stopbyte; ++_byte) \ - if (_name[_byte] != 0xff) { \ - _value = _byte << 3; \ - for (_stopbyte = _name[_byte]; (_stopbyte&0x1); \ - ++_value, _stopbyte >>= 1); \ + register int _bit, _nbits = nbits, _value = -1; \ + for (_bit = 0; _bit < _nbits; ++_bit) \ + if (!bit_test(_name, _bit)) { \ + _value = _bit; \ break; \ } \ *(value) = _value; \ @@ -118,13 +118,10 @@ typedef unsigned char bitstr_t; /* find first bit set in name */ #define bit_ffs(name, nbits, value) { \ register bitstr_t *_name = name; \ - register int _byte, _nbits = nbits; \ - register int _stopbyte = _bit_byte(_nbits), _value = -1; \ - for (_byte = 0; _byte <= _stopbyte; ++_byte) \ - if (_name[_byte]) { \ - _value = _byte << 3; \ - for (_stopbyte = _name[_byte]; !(_stopbyte&0x1); \ - ++_value, _stopbyte >>= 1); \ + register int _bit, _nbits = nbits, _value = -1; \ + for (_bit = 0; _bit < _nbits; ++_bit) \ + if (bit_test(_name, _bit)) { \ + _value = _bit; \ break; \ } \ *(value) = _value; \ |