FatStructs.h File Reference

FAT file structures. More...

This graph shows which files directly or indirectly include this file:

Classes
struct	biosParmBlock
	BIOS parameter block. More...
struct	directoryEntry
	FAT short directory entry. More...
struct	fat32_boot
	Boot sector for a FAT32 volume. More...
struct	fat32_fsinfo
	FSINFO sector for a FAT32 volume. More...
struct	fat_boot
	Boot sector for a FAT12/FAT16 volume. More...
struct	longDirectoryEntry
	FAT long directory entry. More...
struct	masterBootRecord
	Master Boot Record. More...
struct	partitionTable
	MBR partition table entry. More...

Typedefs
typedef struct biosParmBlock	bpb_t
typedef struct directoryEntry	dir_t
typedef struct fat32_boot	fat32_boot_t
typedef struct fat32_fsinfo	fat32_fsinfo_t
typedef struct fat_boot	fat_boot_t
typedef struct longDirectoryEntry	ldir_t
typedef struct masterBootRecord	mbr_t
typedef struct partitionTable	part_t

Functions
static uint8_t	DIR_IS_FILE (const dir_t *dir)
static uint8_t	DIR_IS_FILE_OR_SUBDIR (const dir_t *dir)
static uint8_t	DIR_IS_HIDDEN (const dir_t *dir)
static uint8_t	DIR_IS_LONG_NAME (const dir_t *dir)
static uint8_t	DIR_IS_SUBDIR (const dir_t *dir)
static uint8_t	DIR_IS_SYSTEM (const dir_t *dir)
static uint16_t	FAT_DATE (uint16_t year, uint8_t month, uint8_t day)
static uint8_t	FAT_DAY (uint16_t fatDate)
static uint8_t	FAT_HOUR (uint16_t fatTime)
static uint8_t	FAT_MINUTE (uint16_t fatTime)
static uint8_t	FAT_MONTH (uint16_t fatDate)
static uint8_t	FAT_SECOND (uint16_t fatTime)
static uint16_t	FAT_TIME (uint8_t hour, uint8_t minute, uint8_t second)
static uint16_t	FAT_YEAR (uint16_t fatDate)

Variables
uint8_t const	BOOTSIG0 = 0X55
uint8_t const	BOOTSIG1 = 0XAA
uint8_t const	DIR_ATT_ARCHIVE = 0X20
uint8_t const	DIR_ATT_DEFINED_BITS = 0X3F
uint8_t const	DIR_ATT_DIRECTORY = 0X10
uint8_t const	DIR_ATT_FILE_TYPE_MASK = (DIR_ATT_VOLUME_ID | DIR_ATT_DIRECTORY)
uint8_t const	DIR_ATT_HIDDEN = 0X02
uint8_t const	DIR_ATT_LONG_NAME = 0X0F
uint8_t const	DIR_ATT_LONG_NAME_MASK = 0X3F
uint8_t const	DIR_ATT_READ_ONLY = 0X01
uint8_t const	DIR_ATT_SYSTEM = 0X04
uint8_t const	DIR_ATT_VOLUME_ID = 0X08
uint8_t const	DIR_NAME_0XE5 = 0X05
uint8_t const	DIR_NAME_DELETED = 0XE5
uint8_t const	DIR_NAME_FREE = 0X00
const uint8_t	DIR_NT_LC_BASE = 0X08
const uint8_t	DIR_NT_LC_EXT = 0X10
uint8_t const	EXTENDED_BOOT_SIG = 0X29
uint16_t const	FAT12EOC = 0XFFF
uint16_t const	FAT12EOC_MIN = 0XFF8
uint16_t const	FAT16EOC = 0XFFFF
uint16_t const	FAT16EOC_MIN = 0XFFF8
uint32_t const	FAT32EOC = 0X0FFFFFFF
uint32_t const	FAT32EOC_MIN = 0X0FFFFFF8
uint32_t const	FAT32MASK = 0X0FFFFFFF
uint16_t const	FAT_DEFAULT_DATE = ((2000 - 1980) << 9) | (1 << 5) | 1
uint16_t const	FAT_DEFAULT_TIME = (1 << 11)
uint32_t const	FSINFO_LEAD_SIG = 0x41615252
uint32_t const	FSINFO_STRUCT_SIG = 0x61417272
const uint8_t	LDIR_NAME1_DIM = 5
const uint8_t	LDIR_NAME2_DIM = 6
const uint8_t	LDIR_NAME3_DIM = 2
const uint8_t	LDIR_ORD_LAST_LONG_ENTRY = 0X40

Detailed Description

FAT file structures.

Typedef Documentation

typedef struct biosParmBlock bpb_t

Type name for biosParmBlock

typedef struct directoryEntry dir_t

Type name for directoryEntry

typedef struct fat32_boot fat32_boot_t

Type name for FAT32 Boot Sector

typedef struct fat32_fsinfo fat32_fsinfo_t

Type name for FAT32 FSINFO Sector

typedef struct fat_boot fat_boot_t

Type name for FAT Boot Sector

typedef struct longDirectoryEntry ldir_t

Type name for longDirectoryEntry

typedef struct masterBootRecord mbr_t

Type name for masterBootRecord

typedef struct partitionTable part_t

Type name for partitionTable

Function Documentation

static uint8_t DIR_IS_FILE ( const dir_t *  dir )

inlinestatic

Directory entry is for a file

Parameters

[in]

dir

Pointer to a directory entry.

Returns

true if the entry is for a normal file else false.

static uint8_t DIR_IS_FILE_OR_SUBDIR ( const dir_t *  dir )

inlinestatic

Directory entry is for a file or subdirectory

Parameters

[in]

dir

Pointer to a directory entry.

Returns

true if the entry is for a normal file or subdirectory else false.

static uint8_t DIR_IS_HIDDEN ( const dir_t *  dir )

inlinestatic

Directory entry is hidden

Parameters

[in]

dir

Pointer to a directory entry.

Returns

true if the entry is hidden else false.

static uint8_t DIR_IS_LONG_NAME ( const dir_t *  dir )

inlinestatic

Directory entry is part of a long name

Parameters

[in]

dir

Pointer to a directory entry.

Returns

true if the entry is for part of a long name else false.

static uint8_t DIR_IS_SUBDIR ( const dir_t *  dir )

inlinestatic

Directory entry is for a subdirectory

Parameters

[in]

dir

Pointer to a directory entry.

Returns

true if the entry is for a subdirectory else false.

static uint8_t DIR_IS_SYSTEM ( const dir_t *  dir )

inlinestatic

Directory entry is system type

Parameters

[in]

dir

Pointer to a directory entry.

Returns

true if the entry is system else false.

static uint16_t FAT_DATE ( uint16_t  year, uint8_t  month, uint8_t  day  )

inlinestatic

date field for FAT directory entry

Parameters

[in]	year	[1980,2107]
[in]	month	[1,12]
[in]	day	[1,31]

Returns

Packed date for dir_t entry.

static uint8_t FAT_DAY ( uint16_t  fatDate )

inlinestatic

day part of FAT directory date field

Parameters

[in]

fatDate

Date in packed dir format.

Returns

Extracted day [1,31]

static uint8_t FAT_HOUR ( uint16_t  fatTime )

inlinestatic

hour part of FAT directory time field

Parameters

[in]

fatTime

Time in packed dir format.

Returns

Extracted hour [0,23]

static uint8_t FAT_MINUTE ( uint16_t  fatTime )

inlinestatic

minute part of FAT directory time field

Parameters

[in]

fatTime

Time in packed dir format.

Returns

Extracted minute [0,59]

static uint8_t FAT_MONTH ( uint16_t  fatDate )

inlinestatic

month part of FAT directory date field

Parameters

[in]

fatDate

Date in packed dir format.

Returns

Extracted month [1,12]

static uint8_t FAT_SECOND ( uint16_t  fatTime )

inlinestatic

second part of FAT directory time field Note second/2 is stored in packed time.

Parameters

[in]

fatTime

Time in packed dir format.

Returns

Extracted second [0,58]

static uint16_t FAT_TIME ( uint8_t  hour, uint8_t  minute, uint8_t  second  )

inlinestatic

time field for FAT directory entry

Parameters

[in]	hour	[0,23]
[in]	minute	[0,59]
[in]	second	[0,59]

Returns

Packed time for dir_t entry.

static uint16_t FAT_YEAR ( uint16_t  fatDate )

inlinestatic

year part of FAT directory date field

Parameters

[in]

fatDate

Date in packed dir format.

Returns

Extracted year [1980,2107]

Variable Documentation

uint8_t const BOOTSIG0 = 0X55

Value for byte 510 of boot block or MBR

uint8_t const BOOTSIG1 = 0XAA

Value for byte 511 of boot block or MBR

uint8_t const DIR_ATT_ARCHIVE = 0X20

Old DOS archive bit for backup support

uint8_t const DIR_ATT_DEFINED_BITS = 0X3F

defined attribute bits

uint8_t const DIR_ATT_DIRECTORY = 0X10

Entry is for a directory

uint8_t const DIR_ATT_FILE_TYPE_MASK = (DIR_ATT_VOLUME_ID | DIR_ATT_DIRECTORY)

Mask for file/subdirectory tests

uint8_t const DIR_ATT_HIDDEN = 0X02

File should e hidden in directory listings

uint8_t const DIR_ATT_LONG_NAME = 0X0F

Test value for long name entry. Test is (d->attributes & DIR_ATT_LONG_NAME_MASK) == DIR_ATT_LONG_NAME.

uint8_t const DIR_ATT_LONG_NAME_MASK = 0X3F

Test mask for long name entry

uint8_t const DIR_ATT_READ_ONLY = 0X01

file is read-only

uint8_t const DIR_ATT_SYSTEM = 0X04

Entry is for a system file

uint8_t const DIR_ATT_VOLUME_ID = 0X08

Directory entry contains the volume label

uint8_t const DIR_NAME_0XE5 = 0X05

escape for name[0] = 0XE5

uint8_t const DIR_NAME_DELETED = 0XE5

name[0] value for entry that is free after being "deleted"

uint8_t const DIR_NAME_FREE = 0X00

name[0] value for entry that is free and no allocated entries follow

const uint8_t DIR_NT_LC_BASE = 0X08

Filename base-name is all lower case

const uint8_t DIR_NT_LC_EXT = 0X10

Filename extension is all lower case.

uint8_t const EXTENDED_BOOT_SIG = 0X29

Value for bootSignature field int FAT/FAT32 boot sector

uint16_t const FAT12EOC = 0XFFF

FAT12 end of chain value used by Microsoft.

uint16_t const FAT12EOC_MIN = 0XFF8

Minimum value for FAT12 EOC. Use to test for EOC.

uint16_t const FAT16EOC = 0XFFFF

FAT16 end of chain value used by Microsoft.

uint16_t const FAT16EOC_MIN = 0XFFF8

Minimum value for FAT16 EOC. Use to test for EOC.

uint32_t const FAT32EOC = 0X0FFFFFFF

FAT32 end of chain value used by Microsoft.

uint32_t const FAT32EOC_MIN = 0X0FFFFFF8

Minimum value for FAT32 EOC. Use to test for EOC.

uint32_t const FAT32MASK = 0X0FFFFFFF

Mask a for FAT32 entry. Entries are 28 bits.

uint16_t const FAT_DEFAULT_DATE = ((2000 - 1980) << 9) | (1 << 5) | 1

Default date for file timestamps is 1 Jan 2000

uint16_t const FAT_DEFAULT_TIME = (1 << 11)

Default time for file timestamp is 1 am

uint32_t const FSINFO_LEAD_SIG = 0x41615252

Lead signature for a FSINFO sector

uint32_t const FSINFO_STRUCT_SIG = 0x61417272

Struct signature for a FSINFO sector

const uint8_t LDIR_NAME1_DIM = 5

Dimension of first name field in long directory entry

const uint8_t LDIR_NAME2_DIM = 6

Dimension of first name field in long directory entry

const uint8_t LDIR_NAME3_DIM = 2

Dimension of first name field in long directory entry

const uint8_t LDIR_ORD_LAST_LONG_ENTRY = 0X40

Ord mast that indicates the entry is the last long dir entry in a set of long dir entries. All valid sets of long dir entries must begin with an entry having this mask.