Intravision/reactos
1
0
Fork 0
mirror of https://github.com/reactos/reactos.git synced 2024-11-20 06:15:26 +00:00
Code Issues Projects Releases Packages Wiki Activity
reactos/drivers/filesystems/fastfat_new/fat.h
Victor Perevertkin 34593d933b
[FORMATTING][NTOS][HAL][DRIVERS][SDK] Fix trailing spaces
2021-06-11 15:33:08 +03:00

755 lines
26 KiB
C
Raw Blame History

/*++
Copyright (c) 1989-2000 Microsoft Corporation
Module Name:
Fat.h
Abstract:
This module defines the on-disk structure of the Fat file system.
--*/
#ifndef _FAT_
#define _FAT_
//
// The following nomenclature is used to describe the Fat on-disk
// structure:
//
// LBN - is the number of a sector relative to the start of the disk.
//
// VBN - is the number of a sector relative to the start of a file,
// directory, or allocation.
//
// LBO - is a byte offset relative to the start of the disk.
//
// VBO - is a byte offset relative to the start of a file, directory
// or allocation.
//
typedef LONGLONG LBO; /* for Fat32, LBO is >32 bits */
typedef LBO *PLBO;
typedef ULONG32 VBO;
typedef VBO *PVBO;
//
// The boot sector is the first physical sector (LBN == 0) on the volume.
// Part of the sector contains a BIOS Parameter Block. The BIOS in the
// sector is packed (i.e., unaligned) so we'll supply a unpacking macro
// to translate a packed BIOS into its unpacked equivalent. The unpacked
// BIOS structure is already defined in ntioapi.h so we only need to define
// the packed BIOS.
//
//
// Define the Packed and Unpacked BIOS Parameter Block
//
typedef struct _PACKED_BIOS_PARAMETER_BLOCK {
UCHAR BytesPerSector[2]; // offset = 0x000 0
UCHAR SectorsPerCluster[1]; // offset = 0x002 2
UCHAR ReservedSectors[2]; // offset = 0x003 3
UCHAR Fats[1]; // offset = 0x005 5
UCHAR RootEntries[2]; // offset = 0x006 6
UCHAR Sectors[2]; // offset = 0x008 8
UCHAR Media[1]; // offset = 0x00A 10
UCHAR SectorsPerFat[2]; // offset = 0x00B 11
UCHAR SectorsPerTrack[2]; // offset = 0x00D 13
UCHAR Heads[2]; // offset = 0x00F 15
UCHAR HiddenSectors[4]; // offset = 0x011 17
UCHAR LargeSectors[4]; // offset = 0x015 21
} PACKED_BIOS_PARAMETER_BLOCK; // sizeof = 0x019 25
typedef PACKED_BIOS_PARAMETER_BLOCK *PPACKED_BIOS_PARAMETER_BLOCK;
typedef struct _PACKED_BIOS_PARAMETER_BLOCK_EX {
UCHAR BytesPerSector[2]; // offset = 0x000 0
UCHAR SectorsPerCluster[1]; // offset = 0x002 2
UCHAR ReservedSectors[2]; // offset = 0x003 3
UCHAR Fats[1]; // offset = 0x005 5
UCHAR RootEntries[2]; // offset = 0x006 6
UCHAR Sectors[2]; // offset = 0x008 8
UCHAR Media[1]; // offset = 0x00A 10
UCHAR SectorsPerFat[2]; // offset = 0x00B 11
UCHAR SectorsPerTrack[2]; // offset = 0x00D 13
UCHAR Heads[2]; // offset = 0x00F 15
UCHAR HiddenSectors[4]; // offset = 0x011 17
UCHAR LargeSectors[4]; // offset = 0x015 21
UCHAR LargeSectorsPerFat[4]; // offset = 0x019 25
UCHAR ExtendedFlags[2]; // offset = 0x01D 29
UCHAR FsVersion[2]; // offset = 0x01F 31
UCHAR RootDirFirstCluster[4]; // offset = 0x021 33
UCHAR FsInfoSector[2]; // offset = 0x025 37
UCHAR BackupBootSector[2]; // offset = 0x027 39
UCHAR Reserved[12]; // offset = 0x029 41
} PACKED_BIOS_PARAMETER_BLOCK_EX; // sizeof = 0x035 53
typedef PACKED_BIOS_PARAMETER_BLOCK_EX *PPACKED_BIOS_PARAMETER_BLOCK_EX;
//
// The IsBpbFat32 macro is defined to work with both packed and unpacked
// BPB structures. Since we are only checking for zero, the byte order
// does not matter.
//
#define IsBpbFat32(bpb) (*(USHORT *)(&(bpb)->SectorsPerFat) == 0)
typedef struct BIOS_PARAMETER_BLOCK {
USHORT BytesPerSector;
UCHAR SectorsPerCluster;
USHORT ReservedSectors;
UCHAR Fats;
USHORT RootEntries;
USHORT Sectors;
UCHAR Media;
USHORT SectorsPerFat;
USHORT SectorsPerTrack;
USHORT Heads;
ULONG32 HiddenSectors;
ULONG32 LargeSectors;
ULONG32 LargeSectorsPerFat;
union {
USHORT ExtendedFlags;
struct {
ULONG ActiveFat:4;
ULONG Reserved0:3;
ULONG MirrorDisabled:1;
ULONG Reserved1:8;
};
};
USHORT FsVersion;
ULONG32 RootDirFirstCluster;
USHORT FsInfoSector;
USHORT BackupBootSector;
} BIOS_PARAMETER_BLOCK, *PBIOS_PARAMETER_BLOCK;
//
// This macro takes a Packed BIOS and fills in its Unpacked equivalent
//
#define FatUnpackBios(Bios,Pbios) { \
CopyUchar2(&(Bios)->BytesPerSector, &(Pbios)->BytesPerSector[0] ); \
CopyUchar1(&(Bios)->SectorsPerCluster, &(Pbios)->SectorsPerCluster[0]); \
CopyUchar2(&(Bios)->ReservedSectors, &(Pbios)->ReservedSectors[0] ); \
CopyUchar1(&(Bios)->Fats, &(Pbios)->Fats[0] ); \
CopyUchar2(&(Bios)->RootEntries, &(Pbios)->RootEntries[0] ); \
CopyUchar2(&(Bios)->Sectors, &(Pbios)->Sectors[0] ); \
CopyUchar1(&(Bios)->Media, &(Pbios)->Media[0] ); \
CopyUchar2(&(Bios)->SectorsPerFat, &(Pbios)->SectorsPerFat[0] ); \
CopyUchar2(&(Bios)->SectorsPerTrack, &(Pbios)->SectorsPerTrack[0] ); \
CopyUchar2(&(Bios)->Heads, &(Pbios)->Heads[0] ); \
CopyUchar4(&(Bios)->HiddenSectors, &(Pbios)->HiddenSectors[0] ); \
CopyUchar4(&(Bios)->LargeSectors, &(Pbios)->LargeSectors[0] ); \
CopyUchar4(&(Bios)->LargeSectorsPerFat,&((PPACKED_BIOS_PARAMETER_BLOCK_EX)Pbios)->LargeSectorsPerFat[0] ); \
CopyUchar2(&(Bios)->ExtendedFlags, &((PPACKED_BIOS_PARAMETER_BLOCK_EX)Pbios)->ExtendedFlags[0] ); \
CopyUchar2(&(Bios)->FsVersion, &((PPACKED_BIOS_PARAMETER_BLOCK_EX)Pbios)->FsVersion[0] ); \
CopyUchar4(&(Bios)->RootDirFirstCluster, \
&((PPACKED_BIOS_PARAMETER_BLOCK_EX)Pbios)->RootDirFirstCluster[0] ); \
CopyUchar2(&(Bios)->FsInfoSector, &((PPACKED_BIOS_PARAMETER_BLOCK_EX)Pbios)->FsInfoSector[0] ); \
CopyUchar2(&(Bios)->BackupBootSector, &((PPACKED_BIOS_PARAMETER_BLOCK_EX)Pbios)->BackupBootSector[0] ); \
}
//
// Define the boot sector
//
typedef struct _PACKED_BOOT_SECTOR {
UCHAR Jump[3]; // offset = 0x000 0
UCHAR Oem[8]; // offset = 0x003 3
PACKED_BIOS_PARAMETER_BLOCK PackedBpb; // offset = 0x00B 11
UCHAR PhysicalDriveNumber; // offset = 0x024 36
UCHAR CurrentHead; // offset = 0x025 37
UCHAR Signature; // offset = 0x026 38
UCHAR Id[4]; // offset = 0x027 39
UCHAR VolumeLabel[11]; // offset = 0x02B 43
UCHAR SystemId[8]; // offset = 0x036 54
} PACKED_BOOT_SECTOR; // sizeof = 0x03E 62
typedef PACKED_BOOT_SECTOR *PPACKED_BOOT_SECTOR;
typedef struct _PACKED_BOOT_SECTOR_EX {
UCHAR Jump[3]; // offset = 0x000 0
UCHAR Oem[8]; // offset = 0x003 3
PACKED_BIOS_PARAMETER_BLOCK_EX PackedBpb; // offset = 0x00B 11
UCHAR PhysicalDriveNumber; // offset = 0x040 64
UCHAR CurrentHead; // offset = 0x041 65
UCHAR Signature; // offset = 0x042 66
UCHAR Id[4]; // offset = 0x043 67
UCHAR VolumeLabel[11]; // offset = 0x047 71
UCHAR SystemId[8]; // offset = 0x058 88
} PACKED_BOOT_SECTOR_EX; // sizeof = 0x060 96
typedef PACKED_BOOT_SECTOR_EX *PPACKED_BOOT_SECTOR_EX;
//
// Define the FAT32 FsInfo sector.
//
typedef struct _FSINFO_SECTOR {
ULONG SectorBeginSignature; // offset = 0x000 0
UCHAR ExtraBootCode[480]; // offset = 0x004 4
ULONG FsInfoSignature; // offset = 0x1e4 484
ULONG FreeClusterCount; // offset = 0x1e8 488
ULONG NextFreeCluster; // offset = 0x1ec 492
UCHAR Reserved[12]; // offset = 0x1f0 496
ULONG SectorEndSignature; // offset = 0x1fc 508
} FSINFO_SECTOR, *PFSINFO_SECTOR;
#define FSINFO_SECTOR_BEGIN_SIGNATURE 0x41615252
#define FSINFO_SECTOR_END_SIGNATURE 0xAA550000
#define FSINFO_SIGNATURE 0x61417272
//
// We use the CurrentHead field for our dirty partition info.
//
#define FAT_BOOT_SECTOR_DIRTY 0x01
#define FAT_BOOT_SECTOR_TEST_SURFACE 0x02
//
// Define a Fat Entry type.
//
// This type is used when representing a fat table entry. It also used
// to be used when dealing with a fat table index and a count of entries,
// but the ensuing type casting nightmare sealed this fate. These other
// two types are represented as ULONGs.
//
typedef ULONG32 FAT_ENTRY;
#define FAT32_ENTRY_MASK 0x0FFFFFFFUL
//
// We use these special index values to set the dirty info for
// DOS/Win9x compatibility.
//
#define FAT_CLEAN_VOLUME (~FAT32_ENTRY_MASK | 0)
#define FAT_DIRTY_VOLUME (~FAT32_ENTRY_MASK | 1)
#define FAT_DIRTY_BIT_INDEX 1
//
// Physically, the entry is fully set if clean, and the high
// bit knocked out if it is dirty (i.e., it is really a clean
// bit). This means it is different per-FAT size.
//
#define FAT_CLEAN_ENTRY (~0)
#define FAT12_DIRTY_ENTRY 0x7ff
#define FAT16_DIRTY_ENTRY 0x7fff
#define FAT32_DIRTY_ENTRY 0x7fffffff
//
// The following constants the are the valid Fat index values.
//
#define FAT_CLUSTER_AVAILABLE (FAT_ENTRY)0x00000000
#define FAT_CLUSTER_RESERVED (FAT_ENTRY)0x0ffffff0
#define FAT_CLUSTER_BAD (FAT_ENTRY)0x0ffffff7
#define FAT_CLUSTER_LAST (FAT_ENTRY)0x0fffffff
//
// Fat files have the following time/date structures. Note that the
// following structure is a 32 bits long but USHORT aligned.
//
typedef struct _FAT_TIME {
USHORT DoubleSeconds : 5;
USHORT Minute : 6;
USHORT Hour : 5;
} FAT_TIME;
typedef FAT_TIME *PFAT_TIME;
typedef struct _FAT_DATE {
USHORT Day : 5;
USHORT Month : 4;
USHORT Year : 7; // Relative to 1980
} FAT_DATE;
typedef FAT_DATE *PFAT_DATE;
typedef struct _FAT_TIME_STAMP {
FAT_TIME Time;
FAT_DATE Date;
} FAT_TIME_STAMP;
typedef FAT_TIME_STAMP *PFAT_TIME_STAMP;
//
// Fat files have 8 character file names and 3 character extensions
//
typedef UCHAR FAT8DOT3[11];
typedef FAT8DOT3 *PFAT8DOT3;
//
// The directory entry record exists for every file/directory on the
// disk except for the root directory.
//
typedef struct _PACKED_DIRENT {
FAT8DOT3 FileName; // offset = 0
UCHAR Attributes; // offset = 11
UCHAR NtByte; // offset = 12
UCHAR CreationMSec; // offset = 13
FAT_TIME_STAMP CreationTime; // offset = 14
FAT_DATE LastAccessDate; // offset = 18
union {
USHORT ExtendedAttributes; // offset = 20
USHORT FirstClusterOfFileHi; // offset = 20
};
FAT_TIME_STAMP LastWriteTime; // offset = 22
USHORT FirstClusterOfFile; // offset = 26
ULONG32 FileSize; // offset = 28
} PACKED_DIRENT; // sizeof = 32
typedef PACKED_DIRENT *PPACKED_DIRENT;
//
// A packed dirent is already quadword aligned so simply declare a dirent as a
// packed dirent
//
typedef PACKED_DIRENT DIRENT;
typedef DIRENT *PDIRENT;
//
// The first byte of a dirent describes the dirent. There is also a routine
// to help in deciding how to interpret the dirent.
//
#define FAT_DIRENT_NEVER_USED 0x00
#define FAT_DIRENT_REALLY_0E5 0x05
#define FAT_DIRENT_DIRECTORY_ALIAS 0x2e
#define FAT_DIRENT_DELETED 0xe5
//
// Define the NtByte bits.
//
//
// These two bits are used for EFS on FAT
// 0x1 means the file contents are encrypted
//
// 0x2 means the EFS metadata header is big.
// (this optimization means we don't have to read
// in the first sector of the file stream to get
// the normal header size)
//
#define FAT_DIRENT_NT_BYTE_ENCRYPTED 0x01
#define FAT_DIRENT_NT_BYTE_BIG_HEADER 0x02
//
// These two bits optimize the case in which either the name
// or extension are all lower case.
//
#define FAT_DIRENT_NT_BYTE_8_LOWER_CASE 0x08
#define FAT_DIRENT_NT_BYTE_3_LOWER_CASE 0x10
//
// Define the various dirent attributes
//
#define FAT_DIRENT_ATTR_READ_ONLY 0x01
#define FAT_DIRENT_ATTR_HIDDEN 0x02
#define FAT_DIRENT_ATTR_SYSTEM 0x04
#define FAT_DIRENT_ATTR_VOLUME_ID 0x08
#define FAT_DIRENT_ATTR_DIRECTORY 0x10
#define FAT_DIRENT_ATTR_ARCHIVE 0x20
#define FAT_DIRENT_ATTR_DEVICE 0x40
#define FAT_DIRENT_ATTR_LFN (FAT_DIRENT_ATTR_READ_ONLY | \
FAT_DIRENT_ATTR_HIDDEN | \
FAT_DIRENT_ATTR_SYSTEM | \
FAT_DIRENT_ATTR_VOLUME_ID)
//
// On-disk extension for EFS files.
//
#define FAT_EFS_EXTENSION L".PFILE"
#define FAT_EFS_EXTENSION_CHARCOUNT (6)
#define FAT_EFS_EXTENSION_BYTECOUNT (12)
//
// These macros convert a number of fields in the Bpb to bytes from sectors
//
// ULONG
// FatBytesPerCluster (
// IN PBIOS_PARAMETER_BLOCK Bios
// );
//
// ULONG
// FatBytesPerFat (
// IN PBIOS_PARAMETER_BLOCK Bios
// );
//
// ULONG
// FatReservedBytes (
// IN PBIOS_PARAMETER_BLOCK Bios
// );
//
#define FatBytesPerCluster(B) ((ULONG)((B)->BytesPerSector * (B)->SectorsPerCluster))
#define FatBytesPerFat(B) (IsBpbFat32(B)? \
((ULONG)((B)->BytesPerSector * (B)->LargeSectorsPerFat)) : \
((ULONG)((B)->BytesPerSector * (B)->SectorsPerFat)))
#define FatReservedBytes(B) ((ULONG)((B)->BytesPerSector * (B)->ReservedSectors))
//
// This macro returns the size of the root directory dirent area in bytes
// For Fat32, the root directory is variable in length. This macro returns
// 0 because it is also used to determine the location of cluster 2.
//
// ULONG
// FatRootDirectorySize (
// IN PBIOS_PARAMETER_BLOCK Bios
// );
//
#define FatRootDirectorySize(B) ((ULONG)((B)->RootEntries * sizeof(DIRENT)))
//
// This macro returns the first Lbo (zero based) of the root directory on
// the device. This area is after the reserved and fats.
//
// For Fat32, the root directory is moveable. This macro returns the LBO
// for cluster 2 because it is used to determine the location of cluster 2.
// FatRootDirectoryLbo32() returns the actual LBO of the beginning of the
// actual root directory.
//
// LBO
// FatRootDirectoryLbo (
// IN PBIOS_PARAMETER_BLOCK Bios
// );
//
#define FatRootDirectoryLbo(B) (FatReservedBytes(B) + ((B)->Fats * FatBytesPerFat(B)))
#define FatRootDirectoryLbo32(B) (FatFileAreaLbo(B)+((B)->RootDirFirstCluster-2)*FatBytesPerCluster(B))
//
// This macro returns the first Lbo (zero based) of the file area on the
// the device. This area is after the reserved, fats, and root directory.
//
// LBO
// FatFirstFileAreaLbo (
// IN PBIOS_PARAMTER_BLOCK Bios
// );
//
#define FatFileAreaLbo(B) (FatRootDirectoryLbo(B) + FatRootDirectorySize(B))
//
// This macro returns the number of clusters on the disk. This value is
// computed by taking the total sectors on the disk subtracting up to the
// first file area sector and then dividing by the sectors per cluster count.
// Note that I don't use any of the above macros since far too much
// superfluous sector/byte conversion would take place.
//
// ULONG
// FatNumberOfClusters (
// IN PBIOS_PARAMETER_BLOCK Bios
// );
//
//
// for prior to MS-DOS Version 3.2
//
// After DOS 4.0, at least one of these, Sectors or LargeSectors, will be zero.
// but DOS version 3.2 case, both of these value might contains some value,
// because, before 3.2, we don't have Large Sector entry, some disk might have
// unexpected value in the field, we will use LargeSectors if Sectors eqaul to zero.
//
#define FatNumberOfClusters(B) ( \
\
IsBpbFat32(B) ? \
\
((((B)->Sectors ? (B)->Sectors : (B)->LargeSectors) \
\
- ((B)->ReservedSectors + \
(B)->Fats * (B)->LargeSectorsPerFat )) \
\
/ \
\
(B)->SectorsPerCluster) \
: \
((((B)->Sectors ? (B)->Sectors : (B)->LargeSectors) \
\
- ((B)->ReservedSectors + \
(B)->Fats * (B)->SectorsPerFat + \
(B)->RootEntries * sizeof(DIRENT) / (B)->BytesPerSector ) ) \
\
/ \
\
(B)->SectorsPerCluster) \
)
//
// This macro returns the fat table bit size (i.e., 12 or 16 bits)
//
// ULONG
// FatIndexBitSize (
// IN PBIOS_PARAMETER_BLOCK Bios
// );
//
#define FatIndexBitSize(B) \
((UCHAR)(IsBpbFat32(B) ? 32 : (FatNumberOfClusters(B) < 4087 ? 12 : 16)))
//
// This macro raises STATUS_FILE_CORRUPT and marks the Fcb bad if an
// index value is not within the proper range.
// Note that the first two index values are invalid (0, 1), so we must
// add two from the top end to make sure the everything is within range
//
// VOID
// FatVerifyIndexIsValid (
// IN PIRP_CONTEXT IrpContext,
// IN PVCB Vcb,
// IN ULONG Index
// );
//
#define FatVerifyIndexIsValid(IC,V,I) { \
if (((I) < 2) || ((I) > ((V)->AllocationSupport.NumberOfClusters + 1))) { \
FatRaiseStatus(IC,STATUS_FILE_CORRUPT_ERROR); \
} \
}
//
// These two macros are used to translate between Logical Byte Offsets,
// and fat entry indexes. Note the use of variables stored in the Vcb.
// These two macros are used at a higher level than the other macros
// above.
//
// Note, these indexes are true cluster numbers.
//
// LBO
// GetLboFromFatIndex (
// IN FAT_ENTRY Fat_Index,
// IN PVCB Vcb
// );
//
// FAT_ENTRY
// GetFatIndexFromLbo (
// IN LBO Lbo,
// IN PVCB Vcb
// );
//
#define FatGetLboFromIndex(VCB,FAT_INDEX) ( \
( (LBO) \
(VCB)->AllocationSupport.FileAreaLbo + \
(((LBO)((FAT_INDEX) - 2)) << (VCB)->AllocationSupport.LogOfBytesPerCluster) \
) \
)
#define FatGetIndexFromLbo(VCB,LBO) ( \
(ULONG) ( \
(((LBO) - (VCB)->AllocationSupport.FileAreaLbo) >> \
(VCB)->AllocationSupport.LogOfBytesPerCluster) + 2 \
) \
)
//
// The following macro does the shifting and such to lookup an entry
//
// VOID
// FatLookup12BitEntry(
// IN PVOID Fat,
// IN FAT_ENTRY Index,
// OUT PFAT_ENTRY Entry
// );
//
#define FatLookup12BitEntry(FAT,INDEX,ENTRY) { \
\
CopyUchar2((PUCHAR)(ENTRY), (PUCHAR)(FAT) + (INDEX) * 3 / 2); \
\
*ENTRY = (FAT_ENTRY)(0xfff & (((INDEX) & 1) ? (*(ENTRY) >> 4) : \
*(ENTRY))); \
}
//
// The following macro does the tmp shifting and such to store an entry
//
// VOID
// FatSet12BitEntry(
// IN PVOID Fat,
// IN FAT_ENTRY Index,
// IN FAT_ENTRY Entry
// );
//
#define FatSet12BitEntry(FAT,INDEX,ENTRY) { \
\
FAT_ENTRY TmpFatEntry; \
\
CopyUchar2((PUCHAR)&TmpFatEntry, (PUCHAR)(FAT) + (INDEX) * 3 / 2); \
\
TmpFatEntry = (FAT_ENTRY) \
(((INDEX) & 1) ? ((ENTRY) << 4) | (TmpFatEntry & 0xf) \
: (ENTRY) | (TmpFatEntry & 0xf000)); \
\
*((UNALIGNED UCHAR2 *)((PUCHAR)(FAT) + (INDEX) * 3 / 2)) = *((UNALIGNED UCHAR2 *)(&TmpFatEntry)); \
}
//
// The following macro compares two FAT_TIME_STAMPs
//
#define FatAreTimesEqual(TIME1,TIME2) ( \
RtlEqualMemory((TIME1),(TIME2), sizeof(FAT_TIME_STAMP)) \
)
#define EA_FILE_SIGNATURE (0x4445) // "ED"
#define EA_SET_SIGNATURE (0x4145) // "EA"
//
// If the volume contains any ea data then there is one EA file called
// "EA DATA. SF" located in the root directory as Hidden, System and
// ReadOnly.
//
typedef struct _EA_FILE_HEADER {
USHORT Signature; // offset = 0
USHORT FormatType; // offset = 2
USHORT LogType; // offset = 4
USHORT Cluster1; // offset = 6
USHORT NewCValue1; // offset = 8
USHORT Cluster2; // offset = 10
USHORT NewCValue2; // offset = 12
USHORT Cluster3; // offset = 14
USHORT NewCValue3; // offset = 16
USHORT Handle; // offset = 18
USHORT NewHOffset; // offset = 20
UCHAR Reserved[10]; // offset = 22
USHORT EaBaseTable[240]; // offset = 32
} EA_FILE_HEADER; // sizeof = 512
typedef EA_FILE_HEADER *PEA_FILE_HEADER;
typedef USHORT EA_OFF_TABLE[128];
typedef EA_OFF_TABLE *PEA_OFF_TABLE;
//
// Every file with an extended attribute contains in its dirent an index
// into the EaMapTable. The map table contains an offset within the ea
// file (cluster aligned) of the ea data for the file. The individual
// ea data for each file is prefaced with an Ea Data Header.
//
typedef struct _EA_SET_HEADER {
USHORT Signature; // offset = 0
USHORT OwnEaHandle; // offset = 2
ULONG32 NeedEaCount; // offset = 4
UCHAR OwnerFileName[14]; // offset = 8
UCHAR Reserved[4]; // offset = 22
UCHAR cbList[4]; // offset = 26
UCHAR PackedEas[1]; // offset = 30
} EA_SET_HEADER; // sizeof = 30
typedef EA_SET_HEADER *PEA_SET_HEADER;
#define SIZE_OF_EA_SET_HEADER 30
#define MAXIMUM_EA_SIZE 0x0000ffff
#define GetcbList(EASET) (((EASET)->cbList[0] << 0) + \
((EASET)->cbList[1] << 8) + \
((EASET)->cbList[2] << 16) + \
((EASET)->cbList[3] << 24))
#define SetcbList(EASET,CB) { \
(EASET)->cbList[0] = (CB >> 0) & 0x0ff; \
(EASET)->cbList[1] = (CB >> 8) & 0x0ff; \
(EASET)->cbList[2] = (CB >> 16) & 0x0ff; \
(EASET)->cbList[3] = (CB >> 24) & 0x0ff; \
}
//
// Every individual ea in an ea set is declared the following packed ea
//
typedef struct _PACKED_EA {
UCHAR Flags;
UCHAR EaNameLength;
UCHAR EaValueLength[2];
CHAR EaName[1];
} PACKED_EA;
typedef PACKED_EA *PPACKED_EA;
//
// The following two macros are used to get and set the ea value length
// field of a packed ea
//
// VOID
// GetEaValueLength (
// IN PPACKED_EA Ea,
// OUT PUSHORT ValueLength
// );
//
// VOID
// SetEaValueLength (
// IN PPACKED_EA Ea,
// IN USHORT ValueLength
// );
//
#define GetEaValueLength(EA,LEN) { \
*(LEN) = 0; \
CopyUchar2( (LEN), (EA)->EaValueLength ); \
}
#define SetEaValueLength(EA,LEN) { \
CopyUchar2( &((EA)->EaValueLength), (LEN) ); \
}
//
// The following macro is used to get the size of a packed ea
//
// VOID
// SizeOfPackedEa (
// IN PPACKED_EA Ea,
// OUT PUSHORT EaSize
// );
//
#define SizeOfPackedEa(EA,SIZE) { \
ULONG _NL,_DL; _NL = 0; _DL = 0; \
CopyUchar1(&_NL, &(EA)->EaNameLength); \
GetEaValueLength(EA, &_DL); \
*(SIZE) = 1 + 1 + 2 + _NL + 1 + _DL; \
}
#define EA_NEED_EA_FLAG 0x80
#define MIN_EA_HANDLE 1
#define MAX_EA_HANDLE 30719
#define UNUSED_EA_HANDLE 0xffff
#define EA_CBLIST_OFFSET 0x1a
#define MAX_EA_BASE_INDEX 240
#define MAX_EA_OFFSET_INDEX 128
#endif // _FAT_
Reference in a new issue View git blame Copy permalink