Created
October 3, 2022 22:05
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Simple bitmap data structure
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#ifndef BITMAP_H | |
#define BITMAP_H | |
#include <stdint.h> | |
#include <stdbool.h> | |
#include <stdlib.h> | |
#include <string.h> | |
typedef uint32_t bitmap_t; | |
static inline bitmap_t *bitmap_alloc(size_t n) { | |
return calloc((n >> 5) + (n & 0x1f ? 1 : 0), sizeof(bitmap_t)); | |
} | |
static inline void bitmap_clear(bitmap_t *bitmap, size_t n) { | |
memset(bitmap, 0, ((n >> 5) + (n & 0x1f ? 1 : 0)) * sizeof(bitmap_t)); | |
} | |
static inline bool bitmap_is_bit_set(const bitmap_t *bitmap, size_t bit) { | |
bitmap_t cell = bitmap[bit >> 5]; | |
return (cell >> (bit & 0x1f)) & 1; | |
} | |
static inline void bitmap_set_bit(bitmap_t *bitmap, size_t bit) { | |
bitmap[bit >> 5] |= 1UL << (bit & 0x1f); | |
} | |
static inline void bitmap_clear_bit(bitmap_t *bitmap, size_t bit) { | |
bitmap[bit >> 5] &= ~(1UL << (bit & 0x1f)); | |
} | |
#endif //BITMAP_H |
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