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FAT

include/fs/fat.h

Section titled “include/fs/fat.h”

struct fat12_16_ext_bpb

Section titled “struct 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];
};

struct fat32_ext_bpb

Section titled “struct 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];
};

struct fat_bpb

Section titled “struct 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;
    };
};

struct fat_bpb referenced types:

struct fat_date

Section titled “struct fat_date”
struct fat_date {
    uint16_t  day;
    uint16_t  month;
    uint16_t  year;
};

struct fat_time

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

struct fat_dirent

Section titled “struct 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;
};

struct fat_dirent referenced types:

struct fat_fs

Section titled “struct fat_fs”
struct fat_fs {
    enum fat_fstype           type;
    struct fat_bpb            *bpb;
    struct generic_partition  *partition;
    struct generic_disk       *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];
};

struct fat_fs referenced types:

enum fat_fstype

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

enum fat_fileattr

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

type alias fat_walk_callback

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

type alias fat_walk_callback referenced types:

get_fileattr_string

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

get_fileattr_string referenced types:

Defines

Section titled “Defines”

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