zephyr/subsys/fs/ext2/ext2_bitmap.h

65 lines
1.4 KiB
C

/*
* Copyright (c) 2023 Antmicro <www.antmicro.com>
*
* SPDX-License-Identifier: Apache-2.0
*/
#ifndef __EXT2_BITMAP_H__
#define __EXT2_BITMAP_H__
#include <stdint.h>
#include <stdbool.h>
/* Functions to make operations on bitmaps.
*
* NOTICE: Assumed size of the bitmap is 256 B (1024 bits).
* (Hence, the greatest valid index is 1023.)
*/
/**
* @brief Set bit at given index to one
*
* @param bm Pointer to bitmap
* @param index Index in bitmap
* @param size Size of bitmap in bytes
*
* @retval 0 on success;
* @retval -EINVAL when index is too big;
*/
int ext2_bitmap_set(uint8_t *bm, uint32_t index, uint32_t size);
/**
* @brief Set bit at given index to zero
*
* @param bm Pointer to bitmap
* @param index Index in bitmap
* @param size Size of bitmap in bytes
*
* @retval 0 on success;
* @retval -EINVAL when index is too big;
*/
int ext2_bitmap_unset(uint8_t *bm, uint32_t index, uint32_t size);
/**
* @brief Find first bit set to zero in bitmap
*
* @param bm Pointer to bitmap
* @param size Size of bitmap in bytes
*
* @retval >0 found inode number;
* @retval -ENOSPC when not found;
*/
int32_t ext2_bitmap_find_free(uint8_t *bm, uint32_t size);
/**
* @brief Helper function to count bits set in bitmap
*
* @param bm Pointer to bitmap
* @param size Size of bitmap in bits
*
* @retval Number of set bits in bitmap;
*/
uint32_t ext2_bitmap_count_set(uint8_t *bm, uint32_t size);
#endif /* __EXT2_BITMAP_H__ */