rulimine/stage23/fs/ext2.h
2021-03-04 09:15:10 +01:00

132 lines
2.9 KiB
C

#ifndef __FS__EXT2_H__
#define __FS__EXT2_H__
#include <stdint.h>
#include <stddef.h>
#include <stdbool.h>
#include <lib/part.h>
#include <lib/blib.h>
/* Superblock Fields */
struct ext2_superblock {
uint32_t s_inodes_count;
uint32_t s_blocks_count;
uint32_t s_r_blocks_count;
uint32_t s_free_blocks_count;
uint32_t s_free_inodes_count;
uint32_t s_first_data_block;
uint32_t s_log_block_size;
uint32_t s_log_frag_size;
uint32_t s_blocks_per_group;
uint32_t s_frags_per_group;
uint32_t s_inodes_per_group;
uint32_t s_mtime;
uint32_t s_wtime;
uint16_t s_mnt_count;
uint16_t s_max_mnt_count;
uint16_t s_magic;
uint16_t s_state;
uint16_t s_errors;
uint16_t s_minor_rev_level;
uint32_t s_lastcheck;
uint32_t s_checkinterval;
uint32_t s_creator_os;
uint32_t s_rev_level;
uint16_t s_def_resuid;
uint16_t s_def_gid;
// if version number >= 1, we have to use the ext2 extended superblock as well
/* Extended Superblock */
uint32_t s_first_ino;
uint16_t s_inode_size;
uint16_t s_block_group_nr;
uint32_t s_feature_compat;
uint32_t s_feature_incompat;
uint32_t s_feature_ro_compat;
uint64_t s_uuid[2];
uint64_t s_volume_name[2];
uint64_t s_last_mounted[8];
uint32_t compression_info;
uint8_t prealloc_blocks;
uint8_t prealloc_dir_blocks;
uint16_t reserved_gdt_blocks;
uint8_t journal_uuid[16];
uint32_t journal_inum;
uint32_t journal_dev;
uint32_t last_orphan;
uint32_t hash_seed[4];
uint8_t def_hash_version;
uint8_t jnl_backup_type;
uint16_t group_desc_size;
uint32_t default_mount_opts;
uint32_t first_meta_bg;
uint32_t mkfs_time;
uint32_t jnl_blocks[17];
} __attribute__((packed));
struct ext2_linux {
uint8_t frag_num;
uint8_t frag_size;
uint16_t reserved_16;
uint16_t user_id_high;
uint16_t group_id_high;
uint32_t reserved_32;
} __attribute__((packed));
struct ext2_inode {
uint16_t i_mode;
uint16_t i_uid;
uint32_t i_size;
uint32_t i_atime;
uint32_t i_ctime;
uint32_t i_mtime;
uint32_t i_dtime;
uint16_t i_gid;
uint16_t i_links_count;
uint32_t i_blocks_count;
uint32_t i_flags;
uint32_t i_osd1;
uint32_t i_blocks[15];
uint32_t i_generation;
/* EXT2 v >= 1.0 */
uint32_t i_eab;
uint32_t i_maj;
/* EXT2 vAll */
uint32_t i_frag_block;
struct ext2_linux i_osd2;
} __attribute__((packed));
struct ext2_file_handle {
struct volume *part;
struct ext2_superblock sb;
int size;
struct ext2_inode root_inode;
struct ext2_inode inode;
uint64_t block_size;
uint32_t *alloc_map;
};
int ext2_check_signature(struct volume *part);
bool ext2_get_guid(struct guid *guid, struct volume *part);
int ext2_open(struct ext2_file_handle *ret, struct volume *part, const char *path);
int ext2_read(struct ext2_file_handle *file, void *buf, uint64_t loc, uint64_t count);
#endif