Files
operating-system/src/lib/include/bitmap.h
2024-08-15 18:08:01 +02:00

50 lines
1.5 KiB
C++

#pragma once
#include <stddef.h>
#include <stdint.h>
#include <limits.h>
#include "macros.h"
struct bitmap {
size_t bit_count;
uint32_t* data;
};
/* buf: buffer to use for bitmap
* buf_size: size of buffer in bytes */
#define BITMAP_ATTACH(buf, buf_size) (struct bitmap){.bit_count = buf_size * CHAR_BIT, .data = buf}
static inline int bitmap_set(struct bitmap* bitmap, size_t index)
{
constexpr size_t bits_per_index = sizeof (bitmap->data[0]) * CHAR_BIT;
_Static_assert(bits_per_index == 32);
if (unlikely(index > bitmap->bit_count)) {
return -1;
}
bitmap->data[index / bits_per_index] |= (1 << (index % bits_per_index));
return 0;
}
static inline int bitmap_unset(struct bitmap* bitmap, size_t index)
{
constexpr size_t bits_per_index = sizeof (bitmap->data[0]) * CHAR_BIT;
if (unlikely(index > bitmap->bit_count)) {
return -1;
}
bitmap->data[index / bits_per_index] &= ~(1 << (index % bits_per_index));
return 0;
}
static inline int bitmap_get(struct bitmap* bitmap, size_t index)
{
constexpr size_t bits_per_index = sizeof (bitmap->data[0]) * CHAR_BIT;
if (unlikely(index > bitmap->bit_count)) {
return -1;
}
return !!(bitmap->data[index / bits_per_index] & (1ULL << (index % bits_per_index)));
}
int bitmap_set_range(struct bitmap* bitmap, size_t begin, size_t end);
int bitmap_clear_range(struct bitmap* bitmap, size_t begin, size_t end);
int bitmap_range_empty(struct bitmap* bitmap, size_t begin, size_t end);