@ -20,35 +20,33 @@
*
*
*/
*/
/**
* \ file
* \ brief FAT file structures
*/
/**
/**
* Arduino SdFat Library
* Arduino SdFat Library
* Copyright ( C ) 2009 by William Greiman
* Copyright ( C ) 2009 by William Greiman
*
*
* This file is part of the Arduino Sd2Card Library
* This file is part of the Arduino Sd2Card Library
*/
*/
# ifndef SDFATSTRUCTS_H # ifndef SDFATSTRUCTS_H
# define SDFATSTRUCTS_H # define SDFATSTRUCTS_H
# include <stdint.h> # include <stdint.h>
# define PACKED __attribute__((__packed__)) # define PACKED __attribute__((__packed__))
/**
* \ file
* \ brief FAT file structures
*/
/**
/**
* mostly from Microsoft document fatgen103 . doc
* mostly from Microsoft document fatgen103 . doc
* http : //www.microsoft.com/whdc/system/platform/firmware/fatgen.mspx
* http : //www.microsoft.com/whdc/system/platform/firmware/fatgen.mspx
*/
*/
//------------------------------------------------------------------------------
/** Value for byte 510 of boot block or MBR */ uint8_t const BOOTSIG0 = 0x55 , // Value for byte 510 of boot block or MBR
uint8_t const BOOTSIG0 = 0x55 ; BOOTSIG1 = 0xAA , // Value for byte 511 of boot block or MBR
/** Value for byte 511 of boot block or MBR */ EXTENDED_BOOT_SIG = 0x29 ; // Value for bootSignature field int FAT/FAT32 boot sector
uint8_t const BOOTSIG1 = 0xAA ;
/** Value for bootSignature field int FAT/FAT32 boot sector */
uint8_t const EXTENDED_BOOT_SIG = 0x29 ;
//------------------------------------------------------------------------------
/**
/**
* \ struct partitionTable
* \ struct partitionTable
* \ brief MBR partition table entry
* \ brief MBR partition table entry
@ -57,59 +55,58 @@ uint8_t const EXTENDED_BOOT_SIG = 0x29;
* The MBR partition table has four entries .
* The MBR partition table has four entries .
*/
*/
struct partitionTable { struct partitionTable {
/**
/**
* Boot Indicator . Indicates whether the volume is the active * Boot Indicator . Indicates whether the volume is the active
* partition . Legal values include : 0x00 . Do not use for booting . * partition . Legal values include : 0x00 . Do not use for booting .
* 0x80 Active partition . * 0x80 Active partition .
*/ */
uint8_t boot ;
uint8_t boot ;
/**
/**
* Head part of Cylinder - head - sector address of the first block in * Head part of Cylinder - head - sector address of the first block in
* the partition . Legal values are 0 - 255. Only used in old PC BIOS . * the partition . Legal values are 0 - 255. Only used in old PC BIOS .
*/ */
uint8_t beginHead ;
uint8_t beginHead ;
/**
/**
* Sector part of Cylinder - head - sector address of the first block in * Sector part of Cylinder - head - sector address of the first block in
* the partition . Legal values are 1 - 63. Only used in old PC BIOS . * the partition . Legal values are 1 - 63. Only used in old PC BIOS .
*/ */
unsigned beginSector : 6 ;
unsigned beginSector : 6 ;
/** High bits cylinder for first block in partition. */ /** High bits cylinder for first block in partition. */
unsigned beginCylinderHigh : 2 ;
unsigned beginCylinderHigh : 2 ;
/**
/**
* Combine beginCylinderLow with beginCylinderHigh . Legal values * Combine beginCylinderLow with beginCylinderHigh . Legal values
* are 0 - 1023. Only used in old PC BIOS . * are 0 - 1023. Only used in old PC BIOS .
*/ */
uint8_t beginCylinderLow ;
uint8_t beginCylinderLow ;
/**
/**
* Partition type . See defines that begin with PART_TYPE_ for * Partition type . See defines that begin with PART_TYPE_ for
* some Microsoft partition types . * some Microsoft partition types .
*/ */
uint8_t type ;
uint8_t type ;
/**
/**
* head part of cylinder - head - sector address of the last sector in the * head part of cylinder - head - sector address of the last sector in the
* partition . Legal values are 0 - 255. Only used in old PC BIOS . * partition . Legal values are 0 - 255. Only used in old PC BIOS .
*/ */
uint8_t endHead ;
uint8_t endHead ;
/**
/**
* Sector part of cylinder - head - sector address of the last sector in * Sector part of cylinder - head - sector address of the last sector in
* the partition . Legal values are 1 - 63. Only used in old PC BIOS . * the partition . Legal values are 1 - 63. Only used in old PC BIOS .
*/ */
unsigned endSector : 6 ;
unsigned endSector : 6 ;
/** High bits of end cylinder */ /** High bits of end cylinder */
unsigned endCylinderHigh : 2 ;
unsigned endCylinderHigh : 2 ;
/**
/**
* Combine endCylinderLow with endCylinderHigh . Legal values * Combine endCylinderLow with endCylinderHigh . Legal values
* are 0 - 1023. Only used in old PC BIOS . * are 0 - 1023. Only used in old PC BIOS .
*/ */
uint8_t endCylinderLow ;
uint8_t endCylinderLow ;
/** Logical block address of the first block in the partition. */
uint32_t firstSector ;
uint32_t firstSector ; // Logical block address of the first block in the partition.
/** Length of the partition, in blocks. */
uint32_t totalSectors ; // Length of the partition, in blocks.
uint32_t totalSectors ;
} PACKED ; } PACKED ;
/** Type name for partitionTable */
typedef struct partitionTable part_t ; typedef struct partitionTable part_t ; // Type name for partitionTable
//------------------------------------------------------------------------------
/**
/**
* \ struct masterBootRecord
* \ struct masterBootRecord
*
*
@ -118,22 +115,16 @@ typedef struct partitionTable part_t;
* The first block of a storage device that is formatted with a MBR .
* The first block of a storage device that is formatted with a MBR .
*/
*/
struct masterBootRecord { struct masterBootRecord {
/** Code Area for master boot program. */
uint8_t codeArea [ 440 ] ; // Code Area for master boot program.
uint8_t codeArea [ 440 ] ;
uint32_t diskSignature ; // Optional Windows NT disk signature. May contain boot code.
/** Optional Windows NT disk signature. May contain boot code. */
uint16_t usuallyZero ; // Usually zero but may be more boot code.
uint32_t diskSignature ;
part_t part [ 4 ] ; // Partition tables.
/** Usually zero but may be more boot code. */
uint8_t mbrSig0 ; // First MBR signature byte. Must be 0x55
uint16_t usuallyZero ;
uint8_t mbrSig1 ; // Second MBR signature byte. Must be 0xAA
/** Partition tables. */
part_t part [ 4 ] ;
/** First MBR signature byte. Must be 0x55 */
uint8_t mbrSig0 ;
/** Second MBR signature byte. Must be 0xAA */
uint8_t mbrSig1 ;
} PACKED ; } PACKED ;
/** Type name for masterBootRecord */ /** Type name for masterBootRecord */
typedef struct masterBootRecord mbr_t ; typedef struct masterBootRecord mbr_t ;
//------------------------------------------------------------------------------
/**
/**
* \ struct fat_boot
* \ struct fat_boot
*
*
@ -141,285 +132,280 @@ typedef struct masterBootRecord mbr_t;
*
*
*/
*/
struct fat_boot { struct fat_boot {
/**
/**
* The first three bytes of the boot sector must be valid , * The first three bytes of the boot sector must be valid ,
* executable x 86 - based CPU instructions . This includes a * executable x 86 - based CPU instructions . This includes a
* jump instruction that skips the next nonexecutable bytes . * jump instruction that skips the next nonexecutable bytes .
*/ */
uint8_t jump [ 3 ] ;
uint8_t jump [ 3 ] ;
/**
/**
* This is typically a string of characters that identifies * This is typically a string of characters that identifies
* the operating system that formatted the volume . * the operating system that formatted the volume .
*/ */
char oemId [ 8 ] ;
char oemId [ 8 ] ;
/**
/**
* The size of a hardware sector . Valid decimal values for this * The size of a hardware sector . Valid decimal values for this
* field are 512 , 1024 , 2048 , and 4096. For most disks used in * field are 512 , 1024 , 2048 , and 4096. For most disks used in
* the United States , the value of this field is 512. * the United States , the value of this field is 512.
*/ */
uint16_t bytesPerSector ;
uint16_t bytesPerSector ;
/**
/**
* Number of sectors per allocation unit . This value must be a * Number of sectors per allocation unit . This value must be a
* power of 2 that is greater than 0. The legal values are * power of 2 that is greater than 0. The legal values are
* 1 , 2 , 4 , 8 , 16 , 32 , 64 , and 128. 128 should be avoided . * 1 , 2 , 4 , 8 , 16 , 32 , 64 , and 128. 128 should be avoided .
*/ */
uint8_t sectorsPerCluster ;
uint8_t sectorsPerCluster ;
/**
/**
* The number of sectors preceding the start of the first FAT , * The number of sectors preceding the start of the first FAT ,
* including the boot sector . The value of this field is always 1. * including the boot sector . The value of this field is always 1.
*/ */
uint16_t reservedSectorCount ;
uint16_t reservedSectorCount ;
/**
/**
* The number of copies of the FAT on the volume . * The number of copies of the FAT on the volume .
* The value of this field is always 2. * The value of this field is always 2.
*/ */
uint8_t fatCount ;
uint8_t fatCount ;
/**
/**
* For FAT12 and FAT16 volumes , this field contains the count of * For FAT12 and FAT16 volumes , this field contains the count of
* 32 - byte directory entries in the root directory . For FAT32 volumes , * 32 - byte directory entries in the root directory . For FAT32 volumes ,
* this field must be set to 0. For FAT12 and FAT16 volumes , this * this field must be set to 0. For FAT12 and FAT16 volumes , this
* value should always specify a count that when multiplied by 32 * value should always specify a count that when multiplied by 32
* results in a multiple of bytesPerSector . FAT16 volumes should * results in a multiple of bytesPerSector . FAT16 volumes should
* use the value 512. * use the value 512.
*/ */
uint16_t rootDirEntryCount ;
uint16_t rootDirEntryCount ;
/**
/**
* This field is the old 16 - bit total count of sectors on the volume . * This field is the old 16 - bit total count of sectors on the volume .
* This count includes the count of all sectors in all four regions * This count includes the count of all sectors in all four regions
* of the volume . This field can be 0 ; if it is 0 , then totalSectors32 * of the volume . This field can be 0 ; if it is 0 , then totalSectors32
* must be nonzero . For FAT32 volumes , this field must be 0. For * must be nonzero . For FAT32 volumes , this field must be 0. For
* FAT12 and FAT16 volumes , this field contains the sector count , and * FAT12 and FAT16 volumes , this field contains the sector count , and
* totalSectors32 is 0 if the total sector count fits * totalSectors32 is 0 if the total sector count fits
* ( is less than 0x10000 ) . * ( is less than 0x10000 ) .
*/ */
uint16_t totalSectors16 ;
uint16_t totalSectors16 ;
/**
/**
* This dates back to the old MS - DOS 1. x media determination and is * This dates back to the old MS - DOS 1. x media determination and is
* no longer usually used for anything . 0xF8 is the standard value * no longer usually used for anything . 0xF8 is the standard value
* for fixed ( nonremovable ) media . For removable media , 0xF0 is * for fixed ( nonremovable ) media . For removable media , 0xF0 is
* frequently used . Legal values are 0xF0 or 0xF8 - 0xFF . * frequently used . Legal values are 0xF0 or 0xF8 - 0xFF .
*/ */
uint8_t mediaType ;
uint8_t mediaType ;
/**
/**
* Count of sectors occupied by one FAT on FAT12 / FAT16 volumes . * Count of sectors occupied by one FAT on FAT12 / FAT16 volumes .
* On FAT32 volumes this field must be 0 , and sectorsPerFat32 * On FAT32 volumes this field must be 0 , and sectorsPerFat32
* contains the FAT size count . * contains the FAT size count .
*/ */
uint16_t sectorsPerFat16 ;
uint16_t sectorsPerFat16 ;
/** Sectors per track for interrupt 0x13. Not used otherwise. */
uint16_t sectorsPerTrack ;
uint16_t sectorsPerTrack ; // Sectors per track for interrupt 0x13. Not used otherwise.
/** Number of heads for interrupt 0x13. Not used otherwise. */
uint16_t headCount ; // Number of heads for interrupt 0x13. Not used otherwise.
uint16_t headCount ;
/**
/**
* Count of hidden sectors preceding the partition that contains this * Count of hidden sectors preceding the partition that contains this
* FAT volume . This field is generally only relevant for media * FAT volume . This field is generally only relevant for media
* visible on interrupt 0x13 . * visible on interrupt 0x13 .
*/ */
uint32_t hidddenSectors ;
uint32_t hidddenSectors ;
/**
/**
* This field is the new 32 - bit total count of sectors on the volume . * This field is the new 32 - bit total count of sectors on the volume .
* This count includes the count of all sectors in all four regions * This count includes the count of all sectors in all four regions
* of the volume . This field can be 0 ; if it is 0 , then * of the volume . This field can be 0 ; if it is 0 , then
* totalSectors16 must be nonzero . * totalSectors16 must be nonzero .
*/ */
uint32_t totalSectors32 ;
uint32_t totalSectors32 ;
/**
/**
* Related to the BIOS physical drive number . Floppy drives are * Related to the BIOS physical drive number . Floppy drives are
* identified as 0x00 and physical hard disks are identified as * identified as 0x00 and physical hard disks are identified as
* 0x80 , regardless of the number of physical disk drives . * 0x80 , regardless of the number of physical disk drives .
* Typically , this value is set prior to issuing an INT 13 h BIOS * Typically , this value is set prior to issuing an INT 13 h BIOS
* call to specify the device to access . The value is only * call to specify the device to access . The value is only
* relevant if the device is a boot device . * relevant if the device is a boot device .
*/ */
uint8_t driveNumber ;
uint8_t driveNumber ;
/** used by Windows NT - should be zero for FAT */
uint8_t reserved1 ;
uint8_t reserved1 ; // used by Windows NT - should be zero for FAT
/** 0x29 if next three fields are valid */
uint8_t bootSignature ; // 0x29 if next three fields are valid
uint8_t bootSignature ;
/**
/**
* A random serial number created when formatting a disk , * A random serial number created when formatting a disk ,
* which helps to distinguish between disks . * which helps to distinguish between disks .
* Usually generated by combining date and time . * Usually generated by combining date and time .
*/ */
uint32_t volumeSerialNumber ;
uint32_t volumeSerialNumber ;
/**
/**
* A field once used to store the volume label . The volume label * A field once used to store the volume label . The volume label
* is now stored as a special file in the root directory . * is now stored as a special file in the root directory .
*/ */
char volumeLabel [ 11 ] ;
char volumeLabel [ 11 ] ;
/**
/**
* A field with a value of either FAT , FAT12 or FAT16 , * A field with a value of either FAT , FAT12 or FAT16 ,
* depending on the disk format . * depending on the disk format .
*/ */
char fileSystemType [ 8 ] ;
char fileSystemType [ 8 ] ;
/** X86 boot code */
uint8_t bootCode [ 448 ] ;
uint8_t bootCode [ 448 ] ; // X86 boot code
/** must be 0x55 */
uint8_t bootSectorSig0 ; // must be 0x55
uint8_t bootSectorSig0 ;
uint8_t bootSectorSig1 ; // must be 0xAA
/** must be 0xAA */
uint8_t bootSectorSig1 ;
} PACKED ; } PACKED ;
/** Type name for FAT Boot Sector */
typedef struct fat_boot fat_boot_t ; typedef struct fat_boot fat_boot_t ; // Type name for FAT Boot Sector
//------------------------------------------------------------------------------
/**
/**
* \ struct fat32_boot
* \ struct fat32_boot
*
*
* \ brief Boot sector for a FAT32 volume .
* \ brief Boot sector for a FAT32 volume .
*
*/
*/
struct fat32_boot { struct fat32_boot {
/**
/**
* The first three bytes of the boot sector must be valid , * The first three bytes of the boot sector must be valid ,
* executable x 86 - based CPU instructions . This includes a * executable x 86 - based CPU instructions . This includes a
* jump instruction that skips the next nonexecutable bytes . * jump instruction that skips the next nonexecutable bytes .
*/ */
uint8_t jump [ 3 ] ;
uint8_t jump [ 3 ] ;
/**
/**
* This is typically a string of characters that identifies * This is typically a string of characters that identifies
* the operating system that formatted the volume . * the operating system that formatted the volume .
*/ */
char oemId [ 8 ] ;
char oemId [ 8 ] ;
/**
/**
* The size of a hardware sector . Valid decimal values for this * The size of a hardware sector . Valid decimal values for this
* field are 512 , 1024 , 2048 , and 4096. For most disks used in * field are 512 , 1024 , 2048 , and 4096. For most disks used in
* the United States , the value of this field is 512. * the United States , the value of this field is 512.
*/ */
uint16_t bytesPerSector ;
uint16_t bytesPerSector ;
/**
/**
* Number of sectors per allocation unit . This value must be a * Number of sectors per allocation unit . This value must be a
* power of 2 that is greater than 0. The legal values are * power of 2 that is greater than 0. The legal values are
* 1 , 2 , 4 , 8 , 16 , 32 , 64 , and 128. 128 should be avoided . * 1 , 2 , 4 , 8 , 16 , 32 , 64 , and 128. 128 should be avoided .
*/ */
uint8_t sectorsPerCluster ;
uint8_t sectorsPerCluster ;
/**
/**
* The number of sectors preceding the start of the first FAT , * The number of sectors preceding the start of the first FAT ,
* including the boot sector . Must not be zero * including the boot sector . Must not be zero
*/ */
uint16_t reservedSectorCount ;
uint16_t reservedSectorCount ;
/**
/**
* The number of copies of the FAT on the volume . * The number of copies of the FAT on the volume .
* The value of this field is always 2. * The value of this field is always 2.
*/ */
uint8_t fatCount ;
uint8_t fatCount ;
/**
/**
* FAT12 / FAT16 only . For FAT32 volumes , this field must be set to 0. * FAT12 / FAT16 only . For FAT32 volumes , this field must be set to 0.
*/ */
uint16_t rootDirEntryCount ;
uint16_t rootDirEntryCount ;
/**
/**
* For FAT32 volumes , this field must be 0. * For FAT32 volumes , this field must be 0.
*/ */
uint16_t totalSectors16 ;
uint16_t totalSectors16 ;
/**
/**
* This dates back to the old MS - DOS 1. x media determination and is * This dates back to the old MS - DOS 1. x media determination and is
* no longer usually used for anything . 0xF8 is the standard value * no longer usually used for anything . 0xF8 is the standard value
* for fixed ( nonremovable ) media . For removable media , 0xF0 is * for fixed ( nonremovable ) media . For removable media , 0xF0 is
* frequently used . Legal values are 0xF0 or 0xF8 - 0xFF . * frequently used . Legal values are 0xF0 or 0xF8 - 0xFF .
*/ */
uint8_t mediaType ;
uint8_t mediaType ;
/**
/**
* On FAT32 volumes this field must be 0 , and sectorsPerFat32 * On FAT32 volumes this field must be 0 , and sectorsPerFat32
* contains the FAT size count . * contains the FAT size count .
*/ */
uint16_t sectorsPerFat16 ;
uint16_t sectorsPerFat16 ;
/** Sectors per track for interrupt 0x13. Not used otherwise. */
uint16_t sectorsPerTrack ;
uint16_t sectorsPerTrack ; // Sectors per track for interrupt 0x13. Not used otherwise.
/** Number of heads for interrupt 0x13. Not used otherwise. */
uint16_t headCount ; // Number of heads for interrupt 0x13. Not used otherwise.
uint16_t headCount ;
/**
/**
* Count of hidden sectors preceding the partition that contains this * Count of hidden sectors preceding the partition that contains this
* FAT volume . This field is generally only relevant for media * FAT volume . This field is generally only relevant for media
* visible on interrupt 0x13 . * visible on interrupt 0x13 .
*/ */
uint32_t hidddenSectors ;
uint32_t hidddenSectors ;
/**
/**
* Contains the total number of sectors in the FAT32 volume . * Contains the total number of sectors in the FAT32 volume .
*/ */
uint32_t totalSectors32 ;
uint32_t totalSectors32 ;
/**
/**
* Count of sectors occupied by one FAT on FAT32 volumes . * Count of sectors occupied by one FAT on FAT32 volumes .
*/ */
uint32_t sectorsPerFat32 ;
uint32_t sectorsPerFat32 ;
/**
/**
* This field is only defined for FAT32 media and does not exist on * This field is only defined for FAT32 media and does not exist on
* FAT12 and FAT16 media . * FAT12 and FAT16 media .
* Bits 0 - 3 - - Zero - based number of active FAT . * Bits 0 - 3 - - Zero - based number of active FAT .
* Only valid if mirroring is disabled . * Only valid if mirroring is disabled .
* Bits 4 - 6 - - Reserved . * Bits 4 - 6 - - Reserved .
* Bit 7 - - 0 means the FAT is mirrored at runtime into all FATs . * Bit 7 - - 0 means the FAT is mirrored at runtime into all FATs .
* - - 1 means only one FAT is active ; it is the one referenced * - - 1 means only one FAT is active ; it is the one referenced
* in bits 0 - 3. * in bits 0 - 3.
* Bits 8 - 15 - - Reserved . * Bits 8 - 15 - - Reserved .
*/ */
uint16_t fat32Flags ;
uint16_t fat32Flags ;
/**
/**
* FAT32 version . High byte is major revision number . * FAT32 version . High byte is major revision number .
* Low byte is minor revision number . Only 0.0 define . * Low byte is minor revision number . Only 0.0 define .
*/ */
uint16_t fat32Version ;
uint16_t fat32Version ;
/**
/**
* Cluster number of the first cluster of the root directory for FAT32 . * Cluster number of the first cluster of the root directory for FAT32 .
* This usually 2 but not required to be 2. * This usually 2 but not required to be 2.
*/ */
uint32_t fat32RootCluster ;
uint32_t fat32RootCluster ;
/**
/**
* Sector number of FSINFO structure in the reserved area of the * Sector number of FSINFO structure in the reserved area of the
* FAT32 volume . Usually 1. * FAT32 volume . Usually 1.
*/ */
uint16_t fat32FSInfo ;
uint16_t fat32FSInfo ;
/**
/**
* If nonzero , indicates the sector number in the reserved area * If nonzero , indicates the sector number in the reserved area
* of the volume of a copy of the boot record . Usually 6. * of the volume of a copy of the boot record . Usually 6.
* No value other than 6 is recommended . * No value other than 6 is recommended .
*/ */
uint16_t fat32BackBootBlock ;
uint16_t fat32BackBootBlock ;
/**
/**
* Reserved for future expansion . Code that formats FAT32 volumes * Reserved for future expansion . Code that formats FAT32 volumes
* should always set all of the bytes of this field to 0. * should always set all of the bytes of this field to 0.
*/ */
uint8_t fat32Reserved [ 12 ] ;
uint8_t fat32Reserved [ 12 ] ;
/**
/**
* Related to the BIOS physical drive number . Floppy drives are * Related to the BIOS physical drive number . Floppy drives are
* identified as 0x00 and physical hard disks are identified as * identified as 0x00 and physical hard disks are identified as
* 0x80 , regardless of the number of physical disk drives . * 0x80 , regardless of the number of physical disk drives .
* Typically , this value is set prior to issuing an INT 13 h BIOS * Typically , this value is set prior to issuing an INT 13 h BIOS
* call to specify the device to access . The value is only * call to specify the device to access . The value is only
* relevant if the device is a boot device . * relevant if the device is a boot device .
*/ */
uint8_t driveNumber ;
uint8_t driveNumber ;
/** used by Windows NT - should be zero for FAT */
uint8_t reserved1 ;
uint8_t reserved1 ; // Used by Windows NT - should be zero for FAT
/** 0x29 if next three fields are valid */
uint8_t bootSignature ; // 0x29 if next three fields are valid
uint8_t bootSignature ;
/**
/**
* A random serial number created when formatting a disk , * A random serial number created when formatting a disk ,
* which helps to distinguish between disks . * which helps to distinguish between disks .
* Usually generated by combining date and time . * Usually generated by combining date and time .
*/ */
uint32_t volumeSerialNumber ;
uint32_t volumeSerialNumber ;
/**
/**
* A field once used to store the volume label . The volume label * A field once used to store the volume label . The volume label
* is now stored as a special file in the root directory . * is now stored as a special file in the root directory .
*/ */
char volumeLabel [ 11 ] ;
char volumeLabel [ 11 ] ;
/**
/**
* A text field with a value of FAT32 . * A text field with a value of FAT32 .
*/ */
char fileSystemType [ 8 ] ;
char fileSystemType [ 8 ] ;
/** X86 boot code */
uint8_t bootCode [ 420 ] ;
uint8_t bootCode [ 420 ] ; // X86 boot code
/** must be 0x55 */
uint8_t bootSectorSig0 ; // must be 0x55
uint8_t bootSectorSig0 ;
uint8_t bootSectorSig1 ; // must be 0xAA
/** must be 0xAA */
uint8_t bootSectorSig1 ;
} PACKED ; } PACKED ;
/** Type name for FAT32 Boot Sector */
typedef struct fat32_boot fat32_boot_t ; typedef struct fat32_boot fat32_boot_t ; // Type name for FAT32 Boot Sector
//------------------------------------------------------------------------------
/** Lead signature for a FSINFO sector */ uint32_t const FSINFO_LEAD_SIG = 0x41615252 , // 'AaRR' Lead signature for a FSINFO sector
uint32_t const FSINFO_LEAD_SIG = 0x41615252 ; FSINFO_STRUCT_SIG = 0x61417272 ; // 'aArr' Struct signature for a FSINFO sector
/** Struct signature for a FSINFO sector */
uint32_t const FSINFO_STRUCT_SIG = 0x61417272 ;
/**
/**
* \ struct fat32_fsinfo
* \ struct fat32_fsinfo
*
*
@ -427,12 +413,9 @@ uint32_t const FSINFO_STRUCT_SIG = 0x61417272;
*
*
*/
*/
struct fat32_fsinfo { struct fat32_fsinfo {
/** must be 0x52, 0x52, 0x61, 0x41 */
uint32_t leadSignature ; // must be 0x52, 0x52, 0x61, 0x41 'RRaA'
uint32_t leadSignature ;
uint8_t reserved1 [ 480 ] ; // must be zero
/** must be zero */
uint32_t structSignature ; // must be 0x72, 0x72, 0x41, 0x61 'rrAa'
uint8_t reserved1 [ 480 ] ;
/** must be 0x72, 0x72, 0x41, 0x61 */
uint32_t structSignature ;
/**
/**
* Contains the last known free cluster count on the volume .
* Contains the last known free cluster count on the volume .
* If the value is 0xFFFFFFFF , then the free count is unknown
* If the value is 0xFFFFFFFF , then the free count is unknown
@ -448,30 +431,22 @@ struct fat32_fsinfo {
* should start looking at cluster 2.
* should start looking at cluster 2.
*/
*/
uint32_t nextFree ;
uint32_t nextFree ;
/** must be zero */
uint8_t reserved2 [ 12 ] ;
uint8_t reserved2 [ 12 ] ; // must be zero
/** must be 0x00, 0x00, 0x55, 0xAA */
uint8_t tailSignature [ 4 ] ; // must be 0x00, 0x00, 0x55, 0xAA
uint8_t tailSignature [ 4 ] ;
} PACKED ; } PACKED ;
/** Type name for FAT32 FSINFO Sector */
typedef struct fat32_fsinfo fat32_fsinfo_t ; typedef struct fat32_fsinfo fat32_fsinfo_t ; // Type name for FAT32 FSINFO Sector
//------------------------------------------------------------------------------
// End Of Chain values for FAT entries
// End Of Chain values for FAT entries
/** FAT12 end of chain value used by Microsoft. */ uint16_t const FAT12EOC = 0xFFF , // FAT12 end of chain value used by Microsoft.
uint16_t const FAT12EOC = 0xFFF ; FAT12EOC_MIN = 0xFF8 , // Minimum value for FAT12 EOC. Use to test for EOC.
/** Minimum value for FAT12 EOC. Use to test for EOC. */ FAT16EOC = 0xFFFF , // FAT16 end of chain value used by Microsoft.
uint16_t const FAT12EOC_MIN = 0xFF8 ; FAT16EOC_MIN = 0xFFF8 ; // Minimum value for FAT16 EOC. Use to test for EOC.
/** FAT16 end of chain value used by Microsoft. */ uint32_t const FAT32EOC = 0x0FFFFFFF , // FAT32 end of chain value used by Microsoft.
uint16_t const FAT16EOC = 0xFFFF ; FAT32EOC_MIN = 0x0FFFFFF8 , // Minimum value for FAT32 EOC. Use to test for EOC.
/** Minimum value for FAT16 EOC. Use to test for EOC. */ FAT32MASK = 0x0FFFFFFF ; // Mask a for FAT32 entry. Entries are 28 bits.
uint16_t const FAT16EOC_MIN = 0xFFF8 ;
/** FAT32 end of chain value used by Microsoft. */
uint32_t const FAT32EOC = 0x0FFFFFFF ;
/** Minimum value for FAT32 EOC. Use to test for EOC. */
uint32_t const FAT32EOC_MIN = 0x0FFFFFF8 ;
/** Mask a for FAT32 entry. Entries are 28 bits. */
uint32_t const FAT32MASK = 0x0FFFFFFF ;
//------------------------------------------------------------------------------
/**
/**
* \ struct directoryEntry
* \ struct directoryEntry
* \ brief FAT short directory entry
* \ brief FAT short directory entry
@ -503,54 +478,54 @@ uint32_t const FAT32MASK = 0x0FFFFFFF;
* The valid time range is from Midnight 00 : 00 : 00 to 23 : 59 : 58.
* The valid time range is from Midnight 00 : 00 : 00 to 23 : 59 : 58.
*/
*/
struct directoryEntry { struct directoryEntry {
/** Short 8.3 name.
/**
*
* Short 8.3 name .
* The first eight bytes contain the file name with blank fill .
*
* The last three bytes contain the file extension with blank fill .
* The first eight bytes contain the file name with blank fill .
*/
* The last three bytes contain the file extension with blank fill .
*/
uint8_t name [ 11 ] ;
uint8_t name [ 11 ] ;
/** Entry attributes.
/**
*
* Entry attributes .
* The upper two bits of the attribute byte are reserved and should
*
* always be set to 0 when a file is created and never modified or
* The upper two bits of the attribute byte are reserved and should
* looked at after that . See defines that begin with DIR_ATT_ .
* always be set to 0 when a file is created and never modified or
*/
* looked at after that . See defines that begin with DIR_ATT_ .
*/
uint8_t attributes ;
uint8_t attributes ;
/**
/**
* Reserved for use by Windows NT . Set value to 0 when a file is * Reserved for use by Windows NT . Set value to 0 when a file is
* created and never modify or look at it after that . * created and never modify or look at it after that .
*/ */
uint8_t reservedNT ;
uint8_t reservedNT ;
/**
/**
* The granularity of the seconds part of creationTime is 2 seconds * The granularity of the seconds part of creationTime is 2 seconds
* so this field is a count of tenths of a second and it ' s valid * so this field is a count of tenths of a second and it ' s valid
* value range is 0 - 199 inclusive . ( WHG note - seems to be hundredths ) * value range is 0 - 199 inclusive . ( WHG note - seems to be hundredths )
*/ */
uint8_t creationTimeTenths ;
uint8_t creationTimeTenths ;
/** Time file was created. */
uint16_t creationTime ;
uint16_t creationTime ; // Time file was created.
/** Date file was created. */
uint16_t creationDate ; // Date file was created.
uint16_t creationDate ;
/**
/**
* Last access date . Note that there is no last access time , only * Last access date . Note that there is no last access time , only
* a date . This is the date of last read or write . In the case of * a date . This is the date of last read or write . In the case of
* a write , this should be set to the same date as lastWriteDate . * a write , this should be set to the same date as lastWriteDate .
*/ */
uint16_t lastAccessDate ;
uint16_t lastAccessDate ;
/**
/**
* High word of this entry ' s first cluster number ( always 0 for a * High word of this entry ' s first cluster number ( always 0 for a
* FAT12 or FAT16 volume ) . * FAT12 or FAT16 volume ) .
*/ */
uint16_t firstClusterHigh ;
uint16_t firstClusterHigh ;
/** Time of last write. File creation is considered a write. */
uint16_t lastWriteTime ;
uint16_t lastWriteTime ; // Time of last write. File creation is considered a write.
/** Date of last write. File creation is considered a write. */
uint16_t lastWriteDate ; // Date of last write. File creation is considered a write.
uint16_t lastWriteDate ;
uint16_t firstClusterLow ; // Low word of this entry's first cluster number.
/** Low word of this entry's first cluster number. */
uint32_t fileSize ; // 32-bit unsigned holding this file's size in bytes.
uint16_t firstClusterLow ;
/** 32-bit unsigned holding this file's size in bytes. */
uint32_t fileSize ;
} PACKED ; } PACKED ;
/**
/**
* \ struct directoryVFATEntry
* \ struct directoryVFATEntry
* \ brief VFAT long filename directory entry
* \ brief VFAT long filename directory entry
@ -568,54 +543,36 @@ struct directoryVFATEntry {
* bit 0 - 4 : the position of this long filename block ( first block is 1 )
* bit 0 - 4 : the position of this long filename block ( first block is 1 )
*/
*/
uint8_t sequenceNumber ;
uint8_t sequenceNumber ;
/** First set of UTF-16 characters */
uint16_t name1 [ 5 ] ; //UTF-16
uint16_t name1 [ 5 ] ; // First set of UTF-16 characters
/** attributes (at the same location as in directoryEntry), always 0x0F */
uint8_t attributes ; // attributes (at the same location as in directoryEntry), always 0x0F
uint8_t attributes ;
uint8_t reservedNT ; // Reserved for use by Windows NT. Always 0.
/** Reserved for use by Windows NT. Always 0. */
uint8_t checksum ; // Checksum of the short 8.3 filename, can be used to checked if the file system as modified by a not-long-filename aware implementation.
uint8_t reservedNT ;
uint16_t name2 [ 6 ] ; // Second set of UTF-16 characters
/** Checksum of the short 8.3 filename, can be used to checked if the file system as modified by a not-long-filename aware implementation. */
uint16_t firstClusterLow ; // firstClusterLow is always zero for longFilenames
uint8_t checksum ;
uint16_t name3 [ 2 ] ; // Third set of UTF-16 characters
/** Second set of UTF-16 characters */
uint16_t name2 [ 6 ] ; //UTF-16
/** firstClusterLow is always zero for longFilenames */
uint16_t firstClusterLow ;
/** Third set of UTF-16 characters */
uint16_t name3 [ 2 ] ; //UTF-16
} PACKED ; } PACKED ;
//------------------------------------------------------------------------------
// Definitions for directory entries
// Definitions for directory entries
//
//
/** Type name for directoryEntry */ typedef struct directoryEntry dir_t ; // Type name for directoryEntry
typedef struct directoryEntry dir_t ; typedef struct directoryVFATEntry vfat_t ; // Type name for directoryVFATEntry
/** Type name for directoryVFATEntry */
typedef struct directoryVFATEntry vfat_t ; uint8_t const DIR_NAME_0xE5 = 0x05 , // escape for name[0] = 0xE5
/** escape for name[0] = 0xE5 */ DIR_NAME_DELETED = 0xE5 , // name[0] value for entry that is free after being "deleted"
uint8_t const DIR_NAME_0xE5 = 0x05 ; DIR_NAME_FREE = 0x00 , // name[0] value for entry that is free and no allocated entries follow
/** name[0] value for entry that is free after being "deleted" */ DIR_ATT_READ_ONLY = 0x01 , // file is read-only
uint8_t const DIR_NAME_DELETED = 0xE5 ; DIR_ATT_HIDDEN = 0x02 , // File should hidden in directory listings
/** name[0] value for entry that is free and no allocated entries follow */ DIR_ATT_SYSTEM = 0x04 , // Entry is for a system file
uint8_t const DIR_NAME_FREE = 0x00 ; DIR_ATT_VOLUME_ID = 0x08 , // Directory entry contains the volume label
/** file is read-only */ DIR_ATT_DIRECTORY = 0x10 , // Entry is for a directory
uint8_t const DIR_ATT_READ_ONLY = 0x01 ; DIR_ATT_ARCHIVE = 0x20 , // Old DOS archive bit for backup support
/** File should hidden in directory listings */ 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_HIDDEN = 0x02 ; DIR_ATT_LONG_NAME_MASK = 0x3F , // Test mask for long name entry
/** Entry is for a system file */ DIR_ATT_DEFINED_BITS = 0x3F ; // defined attribute bits
uint8_t const DIR_ATT_SYSTEM = 0x04 ;
/** Directory entry contains the volume label */ /**
uint8_t const DIR_ATT_VOLUME_ID = 0x08 ; * Directory entry is part of a long name
/** Entry is for a directory */
uint8_t const DIR_ATT_DIRECTORY = 0x10 ;
/** Old DOS archive bit for backup support */
uint8_t const DIR_ATT_ARCHIVE = 0x20 ;
/** 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 = 0x0F ;
/** Test mask for long name entry */
uint8_t const DIR_ATT_LONG_NAME_MASK = 0x3F ;
/** defined attribute bits */
uint8_t const DIR_ATT_DEFINED_BITS = 0x3F ;
/** Directory entry is part of a long name
* \ param [ in ] dir Pointer to a directory entry .
* \ param [ in ] dir Pointer to a directory entry .
*
*
* \ return true if the entry is for part of a long name else false .
* \ return true if the entry is for part of a long name else false .
@ -623,9 +580,12 @@ uint8_t const DIR_ATT_DEFINED_BITS = 0x3F;
static inline uint8_t DIR_IS_LONG_NAME ( const dir_t * dir ) { static inline uint8_t DIR_IS_LONG_NAME ( const dir_t * dir ) {
return ( dir - > attributes & DIR_ATT_LONG_NAME_MASK ) = = DIR_ATT_LONG_NAME ;
return ( dir - > attributes & DIR_ATT_LONG_NAME_MASK ) = = DIR_ATT_LONG_NAME ;
} }
/** Mask for file/subdirectory tests */ /** Mask for file/subdirectory tests */
uint8_t const DIR_ATT_FILE_TYPE_MASK = ( DIR_ATT_VOLUME_ID | DIR_ATT_DIRECTORY ) ; uint8_t const DIR_ATT_FILE_TYPE_MASK = ( DIR_ATT_VOLUME_ID | DIR_ATT_DIRECTORY ) ;
/** Directory entry is for a file
/**
* Directory entry is for a file
* \ param [ in ] dir Pointer to a directory entry .
* \ param [ in ] dir Pointer to a directory entry .
*
*
* \ return true if the entry is for a normal file else false .
* \ return true if the entry is for a normal file else false .
@ -633,7 +593,9 @@ uint8_t const DIR_ATT_FILE_TYPE_MASK = (DIR_ATT_VOLUME_ID | DIR_ATT_DIRECTORY);
static inline uint8_t DIR_IS_FILE ( const dir_t * dir ) { static inline uint8_t DIR_IS_FILE ( const dir_t * dir ) {
return ( dir - > attributes & DIR_ATT_FILE_TYPE_MASK ) = = 0 ;
return ( dir - > attributes & DIR_ATT_FILE_TYPE_MASK ) = = 0 ;
} }
/** Directory entry is for a subdirectory
/**
* Directory entry is for a subdirectory
* \ param [ in ] dir Pointer to a directory entry .
* \ param [ in ] dir Pointer to a directory entry .
*
*
* \ return true if the entry is for a subdirectory else false .
* \ return true if the entry is for a subdirectory else false .
@ -641,7 +603,9 @@ static inline uint8_t DIR_IS_FILE(const dir_t* dir) {
static inline uint8_t DIR_IS_SUBDIR ( const dir_t * dir ) { static inline uint8_t DIR_IS_SUBDIR ( const dir_t * dir ) {
return ( dir - > attributes & DIR_ATT_FILE_TYPE_MASK ) = = DIR_ATT_DIRECTORY ;
return ( dir - > attributes & DIR_ATT_FILE_TYPE_MASK ) = = DIR_ATT_DIRECTORY ;
} }
/** Directory entry is for a file or subdirectory
/**
* Directory entry is for a file or subdirectory
* \ param [ in ] dir Pointer to a directory entry .
* \ param [ in ] dir Pointer to a directory entry .
*
*
* \ return true if the entry is for a normal file or subdirectory else false .
* \ return true if the entry is for a normal file or subdirectory else false .
Scott Lahteine
7 years ago