#include "kernel.h"

Data Structures
struct	fat32_fs_info_t
	FAT32 FSINFO structure. More...

struct	fat32_t
	FAT32 filesystem information, used internally by the driver. This is a higher level version of FSINFO. More...

struct	directory_entry_t
	A directory entry, e.g. file, volume label, directory, long filename entry. More...

struct	parameter_block_t
	FAT32 BIOS parameter block (BPB), stored in the boot sector of the drive. More...

struct	lfn_t
	Long filename entry, overlays a directory_entry_t. These entries repeat before a non-lfn entry, each holding up to 13 UCS-2 characters. Note that they are not stored in order, the 'order' attribute indicates which order they go in. More...

Macros
#define	FAT32_SIGNATURE 0x41615252
	FAT32 FSINFO sector signature. More...

#define	FAT32_SIGNATURE2 0x61417272

#define	FAT32_SIGNATURE3 0xAA550000

#define	ATTR_READ_ONLY 0x01

#define	ATTR_HIDDEN 0x02

#define	ATTR_SYSTEM 0x04

#define	ATTR_VOLUME_ID 0x08

#define	ATTR_DIRECTORY 0x10

#define	ATTR_ARCHIVE 0x20

#define	ATTR_LONG_NAME 0x0F

#define	ATTR_LFN_DELETED 0x80

#define	ATTR_LFN_LAST_ENTRY 0x40

#define	DELETED_ENTRY 0xE5

#define	CLUSTER_END 0x0FFFFFF8

#define	CLUSTER_BAD 0x0FFFFFF7

#define	CLUSTER_FREE 0x00000000

#define	GPT_EFI_SYSTEM "28732AC1-1FF8-D211-BA4B-00A0C93EC93B"
	EFI system partition GUID. More...

#define	GPT_MICROSOFT_BASIC_DATA "EBD0A0A2-B9E5-4433-87C0-68B6B72699C7"
	Microsoft basic data partition GUID. More...

Functions
struct fat32_fs_info_t	__attribute__ ((packed)) fat32_fs_info_t
	FAT32 FSINFO structure. More...

void	init_fat32 ()
	Register fat32 as a filesystem type. More...

Variables
uint32_t	signature1

char	reserved1 [480]

uint32_t	structsig

uint32_t	freecount

uint32_t	nextfree

char	reserved2 [12]

uint32_t	trailsig

char	name [11]

uint8_t	attr

uint8_t	nt

uint8_t	create_time_tenths

uint16_t	create_time

uint16_t	create_date

uint16_t	access_date

uint16_t	first_cluster_hi

uint16_t	write_time

uint16_t	write_date

uint16_t	first_cluster_lo

uint32_t	size

uint8_t	code1

uint8_t	code2

uint8_t	code3

char	oemidentifier [8]

uint16_t	bytespersector

uint8_t	sectorspercluster

uint16_t	reservedsectors

uint8_t	numberoffats

uint16_t	numberofdirentries

uint16_t	totalsectors

uint8_t	mediatype

uint16_t	unusedsectorsperfat

uint16_t	sectorspertrack

uint16_t	numberofheads

uint32_t	hiddensectors

uint32_t	sectorsonmedia

uint32_t	sectorsperfat

uint16_t	flags

uint16_t	fatversion

uint32_t	rootdircluster

uint16_t	fsinfocluster

uint16_t	backupbootsectorcluster

char	reserved [12]

uint8_t	drivenumber

uint8_t	ntflags

uint8_t	signature

uint32_t	serialnumber

char	volumelabel [11]

char	systemid [9]

uint8_t	order
	Note the order is arbitrary. It may have the value 0, 3, 65, 48... No way to know! To work around this weirdness, we have an array of lfn_t[256] that holds all possible entries ordered by the order value, which we can then iterate once we encounter a non-lfn to build the name. More...

uint16_t	first [5]

uint8_t	attributes

uint8_t	entry_type

uint8_t	checksum

uint16_t	second [6]

uint16_t	third [2]

Detailed Description

Author: Craig Edwards (craig.nosp@m.edwa.nosp@m.rds@b.nosp@m.rain.nosp@m.box.c.nosp@m.c)

Copyright: Copyright (c) 2012-2023

Macro Definition Documentation

◆ ATTR_ARCHIVE

#define ATTR_ARCHIVE 0x20

◆ ATTR_DIRECTORY

#define ATTR_DIRECTORY 0x10

◆ ATTR_HIDDEN

#define ATTR_HIDDEN 0x02

◆ ATTR_LFN_DELETED

#define ATTR_LFN_DELETED 0x80

◆ ATTR_LFN_LAST_ENTRY

#define ATTR_LFN_LAST_ENTRY 0x40

◆ ATTR_LONG_NAME

#define ATTR_LONG_NAME 0x0F

◆ ATTR_READ_ONLY

#define ATTR_READ_ONLY 0x01

◆ ATTR_SYSTEM

#define ATTR_SYSTEM 0x04

◆ ATTR_VOLUME_ID

#define ATTR_VOLUME_ID 0x08

◆ CLUSTER_BAD

#define CLUSTER_BAD 0x0FFFFFF7

◆ CLUSTER_END

#define CLUSTER_END 0x0FFFFFF8

◆ CLUSTER_FREE

#define CLUSTER_FREE 0x00000000

◆ DELETED_ENTRY

#define DELETED_ENTRY 0xE5

◆ FAT32_SIGNATURE

#define FAT32_SIGNATURE 0x41615252

FAT32 FSINFO sector signature.

◆ FAT32_SIGNATURE2

#define FAT32_SIGNATURE2 0x61417272

◆ FAT32_SIGNATURE3

#define FAT32_SIGNATURE3 0xAA550000

◆ GPT_EFI_SYSTEM

#define GPT_EFI_SYSTEM "28732AC1-1FF8-D211-BA4B-00A0C93EC93B"

EFI system partition GUID.

◆ GPT_MICROSOFT_BASIC_DATA

#define GPT_MICROSOFT_BASIC_DATA "EBD0A0A2-B9E5-4433-87C0-68B6B72699C7"

Microsoft basic data partition GUID.

Function Documentation

◆ attribute()

struct fat32_fs_info_t __attribute__ ( (packed) )

FAT32 FSINFO structure.

Long filename entry, overlays a directory_entry_t. These entries repeat before a non-lfn entry, each holding up to 13 UCS-2 characters. Note that they are not stored in order, the 'order' attribute indicates which order they go in.

FAT32 BIOS parameter block (BPB), stored in the boot sector of the drive.

A directory entry, e.g. file, volume label, directory, long filename entry.

◆ init_fat32()

void init_fat32 ( )

Register fat32 as a filesystem type.

Variable Documentation

◆ access_date

uint16_t access_date

◆ attr

uint8_t attr

◆ attributes

uint8_t attributes

◆ backupbootsectorcluster

uint16_t backupbootsectorcluster

◆ bytespersector

uint16_t bytespersector

◆ checksum

uint8_t checksum

◆ code1

uint8_t code1

◆ code2

uint8_t code2

◆ code3

uint8_t code3

◆ create_date

uint16_t create_date

◆ create_time

uint16_t create_time

◆ create_time_tenths

uint8_t create_time_tenths

◆ drivenumber

uint8_t drivenumber

◆ entry_type

uint8_t entry_type

◆ fatversion

uint16_t fatversion

◆ first

uint16_t first[5]

◆ first_cluster_hi

uint16_t first_cluster_hi

◆ first_cluster_lo

uint16_t first_cluster_lo

◆ flags

uint16_t flags

◆ freecount

uint32_t freecount

◆ fsinfocluster

uint16_t fsinfocluster

◆ hiddensectors

uint32_t hiddensectors

◆ mediatype

uint8_t mediatype

◆ name

char name[11]

◆ nextfree

uint32_t nextfree

◆ nt

uint8_t nt

◆ ntflags

uint8_t ntflags

◆ numberofdirentries

uint16_t numberofdirentries

◆ numberoffats

uint8_t numberoffats

◆ numberofheads

uint16_t numberofheads

◆ oemidentifier

char oemidentifier[8]

◆ order

uint8_t order

Note the order is arbitrary. It may have the value 0, 3, 65, 48... No way to know! To work around this weirdness, we have an array of lfn_t[256] that holds all possible entries ordered by the order value, which we can then iterate once we encounter a non-lfn to build the name.

◆ reserved

uint16_t reserved

◆ reserved1

char reserved1[480]

◆ reserved2

char reserved2[12]

◆ reservedsectors

uint16_t reservedsectors

◆ rootdircluster

uint32_t rootdircluster

◆ second

uint16_t second[6]

◆ sectorsonmedia

uint32_t sectorsonmedia

◆ sectorspercluster

uint8_t sectorspercluster

◆ sectorsperfat

uint32_t sectorsperfat

◆ sectorspertrack

uint16_t sectorspertrack

◆ serialnumber

uint32_t serialnumber

◆ signature

uint8_t signature

◆ signature1

uint32_t signature1

◆ size

uint32_t size

◆ structsig

uint32_t structsig

◆ systemid

char systemid[9]

◆ third

uint16_t third[2]

◆ totalsectors

uint16_t totalsectors

◆ trailsig

uint32_t trailsig

◆ unusedsectorsperfat

uint16_t unusedsectorsperfat

◆ volumelabel

char volumelabel[11]

◆ write_date

uint16_t write_date

◆ write_time

uint16_t write_time

Data Structures

Macros

Functions

Variables