cpython/Parser/bitset.c

76 lines
1.4 KiB
C
Raw Normal View History

1991-02-19 08:39:46 -04:00
/***********************************************************
2000-06-30 20:50:40 -03:00
Copyright (c) 2000, BeOpen.com.
Copyright (c) 1995-2000, Corporation for National Research Initiatives.
Copyright (c) 1990-1995, Stichting Mathematisch Centrum.
All rights reserved.
1991-02-19 08:39:46 -04:00
2000-06-30 20:50:40 -03:00
See the file "Misc/COPYRIGHT" for information on usage and
redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES.
1991-02-19 08:39:46 -04:00
******************************************************************/
1990-12-20 11:06:42 -04:00
/* Bitset primitives used by the parser generator */
1990-10-14 09:07:46 -03:00
1990-12-20 11:06:42 -04:00
#include "pgenheaders.h"
1990-10-14 09:07:46 -03:00
#include "bitset.h"
bitset
newbitset(int nbits)
1990-10-14 09:07:46 -03:00
{
int nbytes = NBYTES(nbits);
1997-04-29 18:03:06 -03:00
bitset ss = PyMem_NEW(BYTE, nbytes);
1990-10-14 09:07:46 -03:00
if (ss == NULL)
1997-04-29 18:03:06 -03:00
Py_FatalError("no mem for bitset");
1990-10-14 09:07:46 -03:00
ss += nbytes;
while (--nbytes >= 0)
*--ss = 0;
return ss;
}
void
delbitset(bitset ss)
1990-10-14 09:07:46 -03:00
{
1997-04-29 18:03:06 -03:00
PyMem_DEL(ss);
1990-10-14 09:07:46 -03:00
}
int
addbit(bitset ss, int ibit)
1990-10-14 09:07:46 -03:00
{
int ibyte = BIT2BYTE(ibit);
BYTE mask = BIT2MASK(ibit);
if (ss[ibyte] & mask)
return 0; /* Bit already set */
ss[ibyte] |= mask;
return 1;
}
#if 0 /* Now a macro */
int
testbit(bitset ss, int ibit)
1990-10-14 09:07:46 -03:00
{
return (ss[BIT2BYTE(ibit)] & BIT2MASK(ibit)) != 0;
}
#endif
int
samebitset(bitset ss1, bitset ss2, int nbits)
1990-10-14 09:07:46 -03:00
{
int i;
for (i = NBYTES(nbits); --i >= 0; )
if (*ss1++ != *ss2++)
return 0;
return 1;
}
void
mergebitset(bitset ss1, bitset ss2, int nbits)
1990-10-14 09:07:46 -03:00
{
int i;
for (i = NBYTES(nbits); --i >= 0; )
*ss1++ |= *ss2++;
}