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#ifndef XC_BITOPS_H
#define XC_BITOPS_H 1
/* bitmap operations for single threaded access */
#include <stdlib.h>
#include <string.h>
#ifdef __LP64__
#define BITS_PER_LONG 64
#else
#define BITS_PER_LONG 32
#endif
#define BITMAP_ENTRY(_nr,_bmap) ((_bmap))[(_nr) / 8]
#define BITMAP_SHIFT(_nr) ((_nr) % 8)
/* calculate required space for number of bytes needed to hold nr_bits */
static inline unsigned long bitmap_size(unsigned long nr_bits)
{
return (nr_bits + 7) / 8;
}
static inline void *bitmap_alloc(unsigned long nr_bits)
{
unsigned long longs;
longs = (nr_bits + BITS_PER_LONG - 1) / BITS_PER_LONG;
return calloc(longs, sizeof(unsigned long));
}
static inline void bitmap_set(void *addr, unsigned long nr_bits)
{
memset(addr, 0xff, bitmap_size(nr_bits));
}
static inline void bitmap_clear(void *addr, unsigned long nr_bits)
{
memset(addr, 0, bitmap_size(nr_bits));
}
static inline int test_bit(unsigned long nr, const void *_addr)
{
const char *addr = _addr;
return (BITMAP_ENTRY(nr, addr) >> BITMAP_SHIFT(nr)) & 1;
}
static inline void clear_bit(unsigned long nr, void *_addr)
{
char *addr = _addr;
BITMAP_ENTRY(nr, addr) &= ~(1UL << BITMAP_SHIFT(nr));
}
static inline void set_bit(unsigned long nr, void *_addr)
{
char *addr = _addr;
BITMAP_ENTRY(nr, addr) |= (1UL << BITMAP_SHIFT(nr));
}
static inline int test_and_clear_bit(unsigned long nr, void *addr)
{
int oldbit = test_bit(nr, addr);
clear_bit(nr, addr);
return oldbit;
}
static inline int test_and_set_bit(unsigned long nr, void *addr)
{
int oldbit = test_bit(nr, addr);
set_bit(nr, addr);
return oldbit;
}
static inline void bitmap_or(void *_dst, const void *_other,
unsigned long nr_bits)
{
char *dst = _dst;
const char *other = _other;
unsigned long i;
for ( i = 0; i < bitmap_size(nr_bits); ++i )
dst[i] |= other[i];
}
#endif /* XC_BITOPS_H */
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