diff options
Diffstat (limited to 'tools')
-rw-r--r-- | tools/libxc/xc_bitops.h | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/tools/libxc/xc_bitops.h b/tools/libxc/xc_bitops.h new file mode 100644 index 0000000000..d8e0c168d7 --- /dev/null +++ b/tools/libxc/xc_bitops.h @@ -0,0 +1,63 @@ +#ifndef XC_BITOPS_H +#define XC_BITOPS_H 1 + +/* bitmap operations for single threaded access */ + +#include <stdlib.h> +#include <string.h> + +#define BITS_PER_LONG (sizeof(unsigned long) * 8) +#define ORDER_LONG (sizeof(unsigned long) == 4 ? 5 : 6) + +#define BITMAP_ENTRY(_nr,_bmap) ((_bmap))[(_nr)/BITS_PER_LONG] +#define BITMAP_SHIFT(_nr) ((_nr) % BITS_PER_LONG) + +/* calculate required space for number of longs needed to hold nr_bits */ +static inline int bitmap_size(int nr_bits) +{ + int nr_long, nr_bytes; + nr_long = (nr_bits + BITS_PER_LONG - 1) >> ORDER_LONG; + nr_bytes = nr_long * sizeof(unsigned long); + return nr_bytes; +} + +static inline unsigned long *bitmap_alloc(int nr_bits) +{ + return calloc(1, bitmap_size(nr_bits)); +} + +static inline void bitmap_clear(unsigned long *addr, int nr_bits) +{ + memset(addr, 0, bitmap_size(nr_bits)); +} + +static inline int test_bit(int nr, unsigned long *addr) +{ + return (BITMAP_ENTRY(nr, addr) >> BITMAP_SHIFT(nr)) & 1; +} + +static inline void clear_bit(int nr, unsigned long *addr) +{ + BITMAP_ENTRY(nr, addr) &= ~(1UL << BITMAP_SHIFT(nr)); +} + +static inline void set_bit(int nr, unsigned long *addr) +{ + BITMAP_ENTRY(nr, addr) |= (1UL << BITMAP_SHIFT(nr)); +} + +static inline int test_and_clear_bit(int nr, unsigned long *addr) +{ + int oldbit = test_bit(nr, addr); + clear_bit(nr, addr); + return oldbit; +} + +static inline int test_and_set_bit(int nr, unsigned long *addr) +{ + int oldbit = test_bit(nr, addr); + set_bit(nr, addr); + return oldbit; +} + +#endif /* XC_BITOPS_H */ |