home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
OS/2 Shareware BBS: 10 Tools
/
10-Tools.zip
/
snip9707.zip
/
BITARRAY.C
< prev
next >
Wrap
C/C++ Source or Header
|
1997-07-05
|
848b
|
35 lines
/* +++Date last modified: 05-Jul-1997 */
/*
** Functions to maintain an arbitrary length array of bits
*/
#include "bitops.h"
char *alloc_bit_array(size_t bits)
{
char *set = calloc((bits + CHAR_BIT - 1) / CHAR_BIT, sizeof(char));
return set;
}
int getbit(char *set, int number)
{
set += number / CHAR_BIT;
return (*set & (1 << (number % CHAR_BIT))) != 0; /* 0 or 1 */
}
void setbit(char *set, int number, int value)
{
set += number / CHAR_BIT;
if (value)
*set |= 1 << (number % CHAR_BIT); /* set bit */
else *set &= ~(1 << (number % CHAR_BIT)); /* clear bit*/
}
void flipbit(char *set, int number)
{
set += number / CHAR_BIT;
*set ^= 1 << (number % CHAR_BIT); /* flip bit */
}