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FAT

include/fs/fat.h View source View on GitHub

Structs

Section titled “Structs”

fat12_16_ext_bpb

Section titled “fat12_16_ext_bpb”
struct fat12_16_ext_bpb {
    uint8_t   drive_number;
    uint8_t   reserved;
    uint8_t   boot_signature;
    uint32_t  volume_id;
    uint8_t   volume_label[11];
    uint8_t   fs_type[8];
    uint8_t   reserved1[448];
};

fat32_ext_bpb

Section titled “fat32_ext_bpb”
struct fat32_ext_bpb {
    uint32_t  fat_size_32;
    uint16_t  ext_flags;
    uint16_t  fs_version;
    uint32_t  root_cluster;
    uint16_t  fs_info;
    uint16_t  backup_boot_sector;
    uint8_t   reserved[12];
    uint8_t   drive_number;
    uint8_t   reserved1;
    uint8_t   boot_signature;
    uint32_t  volume_id;
    uint8_t   volume_label[11];
    uint8_t   fs_type[8];
    uint8_t   reserved2[420];
};

fat_bpb

Section titled “fat_bpb”
struct fat_bpb {
    uint8_t   jump_boot[3];
    uint8_t   oem_name[8];
    uint16_t  bytes_per_sector;
    uint8_t   sectors_per_cluster;
    uint16_t  reserved_sector_count;
    uint8_t   num_fats;
    uint16_t  root_entry_count;
    uint16_t  total_sectors_16;
    uint8_t   media;
    uint16_t  fat_size_16;
    uint16_t  sectors_per_track;
    uint16_t  num_heads;
    uint32_t  hidden_sectors;
    uint32_t  total_sectors_32;
    union {
        struct fat32_ext_bpb     ext_32;
        struct fat12_16_ext_bpb  ext_12_16;
    };
};

fat_date

Section titled “fat_date”
struct fat_date {
    uint16_t  day : 5;
    uint16_t  month : 4;
    uint16_t  year : 7;
};

fat_time

Section titled “fat_time”
struct fat_time {
    uint16_t  second : 5;
    uint16_t  minute : 6;
    uint16_t  hour : 5;
};

fat_dirent

Section titled “fat_dirent”
struct fat_dirent {
    char               name[11];
    enum fat_fileattr  attr;
    uint8_t            ntres;
    uint8_t            crttimetenth;
    struct fat_time    crttime;
    struct fat_date    crtdate;
    struct fat_date    lastaccess;
    uint16_t           high_cluster;
    struct fat_time    modtime;
    struct fat_date    moddate;
    uint16_t           low_cluster;
    uint32_t           filesize;
};

fat_fs

Section titled “fat_fs”
struct fat_fs {
    enum fat_fstype      type;
    struct fat_bpb       *bpb;
    struct partition     *partition;
    struct block_device  *disk;
    uint32_t             volume_base_lba;
    uint32_t             total_clusters;
    uint32_t             root_cluster;
    uint32_t             cluster_size;
    uint32_t             fsinfo_sector;
    uint32_t             free_clusters;
    uint32_t             last_alloc_cluster;
    uint32_t             entries_per_cluster;
    uint16_t             fat_size;
    uint8_t              boot_signature;
    uint8_t              drive_number;
    uint32_t             volume_id;
    uint8_t              volume_label[11];
    uint8_t              fs_type[8];
};

Enums

Section titled “Enums”

fat_fstype

Section titled “fat_fstype”
enum fat_fstype : uint8_t {
    FAT_12,
    FAT_16,
    FAT_32,
};

fat_fileattr

Section titled “fat_fileattr”
enum fat_fileattr : uint8_t {
    FAT_RO = 0x01,
    FAT_HIDDEN = 0x02,
    FAT_SYSTEM = 0x04,
    FAT_VOL_ID = 0x08,
    FAT_DIR = 0x10,
    FAT_ARCHIVE = 0x20,
};

Type Aliases

Section titled “Type Aliases”

fat_walk_callback

Section titled “fat_walk_callback”
typedef bool (*fat_walk_callback)(struct fat_dirent * *, uint32_t, void * *);

Functions

Section titled “Functions”

get_fileattr_string

Section titled “get_fileattr_string”
char get_fileattr_string(enum fat_fileattr f);

fat32_read_bpb

Section titled “fat32_read_bpb”
struct fat_bpb * fat32_read_bpb(struct partition * *);

fat12_16_print_bpb

Section titled “fat12_16_print_bpb”
void fat12_16_print_bpb(const struct fat_bpb *bpb);

fat_eoc

Section titled “fat_eoc”
uint32_t fat_eoc(struct fat_fs *fs);

fat_is_eoc

Section titled “fat_is_eoc”
bool fat_is_eoc(struct fat_fs *fs, uint32_t cluster);

fat_get_dir_cluster

Section titled “fat_get_dir_cluster”
uint32_t fat_get_dir_cluster(struct fat_dirent *d);

fat_format_filename_83

Section titled “fat_format_filename_83”
void fat_format_filename_83(const char *name, char out[11]);

fat_first_data_sector

Section titled “fat_first_data_sector”
uint32_t fat_first_data_sector(const struct fat_fs *fs);

fat_cluster_to_lba

Section titled “fat_cluster_to_lba”
uint32_t fat_cluster_to_lba(const struct fat_fs *fs, uint32_t cluster);

fat_get_current_date

Section titled “fat_get_current_date”
struct fat_date fat_get_current_date();

fat_get_current_time

Section titled “fat_get_current_time”
struct fat_time fat_get_current_time();

fat_g_mount

Section titled “fat_g_mount”
struct vfs_node * fat_g_mount(struct partition *p);

fat_g_print

Section titled “fat_g_print”
void fat_g_print(struct partition * *);

fat32_print_bpb

Section titled “fat32_print_bpb”
void fat32_print_bpb(const struct fat_bpb *bpb);

fat_print_dirent

Section titled “fat_print_dirent”
void fat_print_dirent(const struct fat_dirent *ent);

fat_list_root

Section titled “fat_list_root”
void fat_list_root(struct fat_fs *fs);

fat_read_cluster

Section titled “fat_read_cluster”
bool fat_read_cluster(struct fat_fs *fs, uint32_t cluster, uint8_t *buffer);

fat_write_cluster

Section titled “fat_write_cluster”
bool fat_write_cluster(struct fat_fs *fs, uint32_t cluster, const uint8_t *buffer);

fat_write_dirent

Section titled “fat_write_dirent”
bool fat_write_dirent(struct fat_fs *fs, uint32_t dir_cluster, const struct fat_dirent *dirent_to_write, uint32_t entry_index);

fat_write_fat_entry

Section titled “fat_write_fat_entry”
bool fat_write_fat_entry(struct fat_fs *fs, uint32_t cluster, uint32_t value);

fat_read_fat_entry

Section titled “fat_read_fat_entry”
uint32_t fat_read_fat_entry(struct fat_fs *fs, uint32_t cluster);

fat_alloc_cluster

Section titled “fat_alloc_cluster”
uint32_t fat_alloc_cluster(struct fat_fs *fs);

fat_free_chain

Section titled “fat_free_chain”
void fat_free_chain(struct fat_fs *fs, uint32_t start_cluster);

fat_write_fsinfo

Section titled “fat_write_fsinfo”
void fat_write_fsinfo(struct fat_fs *fs);

fat_create

Section titled “fat_create”
bool fat_create(struct fat_fs *fs, uint32_t dir_cluster, const char *filename, struct fat_dirent *out_dirent, enum fat_fileattr attr, uint32_t *out_cluster);

fat_delete

Section titled “fat_delete”
bool fat_delete(struct fat_fs *fs, uint32_t dir_cluster, const char *filename);

fat_rename

Section titled “fat_rename”
bool fat_rename(struct fat_fs *fs, uint32_t dir_cluster, const char *filename, const char *new_filename);

fat_read_file

Section titled “fat_read_file”
bool fat_read_file(struct fat_fs *fs, struct fat_dirent *ent, uint32_t offset, uint32_t size, uint8_t *out_buf);

fat_write_file

Section titled “fat_write_file”
bool fat_write_file(struct fat_fs *fs, struct fat_dirent *ent, uint32_t offset, const uint8_t *data, uint32_t size);

fat_walk_cluster

Section titled “fat_walk_cluster”
bool fat_walk_cluster(struct fat_fs *fs, uint32_t cluster, fat_walk_callback cb, void *ctx);

fat_lookup

Section titled “fat_lookup”
struct fat_dirent * fat_lookup(struct fat_fs *fs, uint32_t cluster, const char *f, uint32_t *out_index);

fat_contains

Section titled “fat_contains”
bool fat_contains(struct fat_fs *fs, uint32_t cluster, const char *f);

fat_mkdir

Section titled “fat_mkdir”
bool fat_mkdir(struct fat_fs *fs, uint32_t parent_cluster, const char *name, struct fat_dirent *out_dirent);

Macros

Section titled “Macros”

FAT12_PARTITION_TYPE

Section titled “FAT12_PARTITION_TYPE”
#define FAT12_PARTITION_TYPE 0x01  // FAT12, CHS addressing

FAT16_PARTITION_TYPE

Section titled “FAT16_PARTITION_TYPE”
#define FAT16_PARTITION_TYPE 0x04  // FAT16, CHS addressing (less than 32MB)

FAT16_PARTITION_TYPE2

Section titled “FAT16_PARTITION_TYPE2”
#define FAT16_PARTITION_TYPE2 0x06 // FAT16, LBA addressing (greater than 32MB)

FAT32_PARTITION_TYPE1

Section titled “FAT32_PARTITION_TYPE1”
#define FAT32_PARTITION_TYPE1 0x0B // FAT32, CHS addressing

FAT32_PARTITION_TYPE2

Section titled “FAT32_PARTITION_TYPE2”
#define FAT32_PARTITION_TYPE2 0x0C // FAT32, LBA addressing

FAT_DIR_CLUSTER_ROOT

Section titled “FAT_DIR_CLUSTER_ROOT”
#define FAT_DIR_CLUSTER_ROOT 0xFFFFFFFF