78e468e3a53059f7ee8149a4aca91e8ebe8ac14a
[reactos.git] / freeldr / freeldr / fs / fat.h
1 /*
2 * FreeLoader
3 * Copyright (C) 2001 Brian Palmer <brianp@sginet.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19
20 #ifndef __FAT_H
21 #define __FAT_H
22
23 typedef struct _FAT_BOOTSECTOR
24 {
25 BYTE JumpBoot[3]; // Jump instruction to boot code
26 UCHAR OemName[8]; // "MSWIN4.1" for MS formatted volumes
27 WORD BytesPerSector; // Bytes per sector
28 BYTE SectorsPerCluster; // Number of sectors in a cluster
29 WORD ReservedSectors; // Reserved sectors, usually 1 (the bootsector)
30 BYTE NumberOfFats; // Number of FAT tables
31 WORD RootDirEntries; // Number of root directory entries (fat12/16)
32 WORD TotalSectors; // Number of total sectors on the drive, 16-bit
33 BYTE MediaDescriptor; // Media descriptor byte
34 WORD SectorsPerFat; // Sectors per FAT table (fat12/16)
35 WORD SectorsPerTrack; // Number of sectors in a track
36 WORD NumberOfHeads; // Number of heads on the disk
37 DWORD HiddenSectors; // Hidden sectors (sectors before the partition start like the partition table)
38 DWORD TotalSectorsBig; // This field is the new 32-bit total count of sectors on the volume
39 BYTE DriveNumber; // Int 0x13 drive number (e.g. 0x80)
40 BYTE Reserved1; // Reserved (used by Windows NT). Code that formats FAT volumes should always set this byte to 0.
41 BYTE BootSignature; // Extended boot signature (0x29). This is a signature byte that indicates that the following three fields in the boot sector are present.
42 DWORD VolumeSerialNumber; // Volume serial number
43 UCHAR VolumeLabel[11]; // Volume label. This field matches the 11-byte volume label recorded in the root directory
44 UCHAR FileSystemType[8]; // One of the strings "FAT12 ", "FAT16 ", or "FAT "
45
46 BYTE BootCodeAndData[448]; // The remainder of the boot sector
47
48 WORD BootSectorMagic; // 0xAA55
49
50 } PACKED FAT_BOOTSECTOR, *PFAT_BOOTSECTOR;
51
52 typedef struct _FAT32_BOOTSECTOR
53 {
54 BYTE JumpBoot[3]; // Jump instruction to boot code
55 UCHAR OemName[8]; // "MSWIN4.1" for MS formatted volumes
56 WORD BytesPerSector; // Bytes per sector
57 BYTE SectorsPerCluster; // Number of sectors in a cluster
58 WORD ReservedSectors; // Reserved sectors, usually 1 (the bootsector)
59 BYTE NumberOfFats; // Number of FAT tables
60 WORD RootDirEntries; // Number of root directory entries (fat12/16)
61 WORD TotalSectors; // Number of total sectors on the drive, 16-bit
62 BYTE MediaDescriptor; // Media descriptor byte
63 WORD SectorsPerFat; // Sectors per FAT table (fat12/16)
64 WORD SectorsPerTrack; // Number of sectors in a track
65 WORD NumberOfHeads; // Number of heads on the disk
66 DWORD HiddenSectors; // Hidden sectors (sectors before the partition start like the partition table)
67 DWORD TotalSectorsBig; // This field is the new 32-bit total count of sectors on the volume
68 DWORD SectorsPerFatBig; // This field is the FAT32 32-bit count of sectors occupied by ONE FAT. BPB_FATSz16 must be 0
69 WORD ExtendedFlags; // Extended flags (fat32)
70 WORD FileSystemVersion; // File system version (fat32)
71 DWORD RootDirStartCluster; // Starting cluster of the root directory (fat32)
72 WORD FsInfo; // Sector number of FSINFO structure in the reserved area of the FAT32 volume. Usually 1.
73 WORD BackupBootSector; // If non-zero, indicates the sector number in the reserved area of the volume of a copy of the boot record. Usually 6.
74 BYTE Reserved[12]; // Reserved for future expansion
75 BYTE DriveNumber; // Int 0x13 drive number (e.g. 0x80)
76 BYTE Reserved1; // Reserved (used by Windows NT). Code that formats FAT volumes should always set this byte to 0.
77 BYTE BootSignature; // Extended boot signature (0x29). This is a signature byte that indicates that the following three fields in the boot sector are present.
78 DWORD VolumeSerialNumber; // Volume serial number
79 UCHAR VolumeLabel[11]; // Volume label. This field matches the 11-byte volume label recorded in the root directory
80 UCHAR FileSystemType[8]; // Always set to the string "FAT32 "
81
82 BYTE BootCodeAndData[420]; // The remainder of the boot sector
83
84 WORD BootSectorMagic; // 0xAA55
85
86 } PACKED FAT32_BOOTSECTOR, *PFAT32_BOOTSECTOR;
87
88 /*
89 * Structure of MSDOS directory entry
90 */
91 typedef struct //_DIRENTRY
92 {
93 UCHAR FileName[11]; /* Filename + extension */
94 UINT8 Attr; /* File attributes */
95 UINT8 ReservedNT; /* Reserved for use by Windows NT */
96 UINT8 TimeInTenths; /* Millisecond stamp at file creation */
97 UINT16 CreateTime; /* Time file was created */
98 UINT16 CreateDate; /* Date file was created */
99 UINT16 LastAccessDate; /* Date file was last accessed */
100 UINT16 ClusterHigh; /* High word of this entry's start cluster */
101 UINT16 Time; /* Time last modified */
102 UINT16 Date; /* Date last modified */
103 UINT16 ClusterLow; /* First cluster number low word */
104 UINT32 Size; /* File size */
105 } PACKED DIRENTRY, * PDIRENTRY;
106
107 typedef struct
108 {
109 UINT8 SequenceNumber; /* Sequence number for slot */
110 WCHAR Name0_4[5]; /* First 5 characters in name */
111 UINT8 EntryAttributes; /* Attribute byte */
112 UINT8 Reserved; /* Always 0 */
113 UINT8 AliasChecksum; /* Checksum for 8.3 alias */
114 WCHAR Name5_10[6]; /* 6 more characters in name */
115 UINT16 StartCluster; /* Starting cluster number */
116 WCHAR Name11_12[2]; /* Last 2 characters in name */
117 } PACKED LFN_DIRENTRY, * PLFN_DIRENTRY;
118
119 typedef struct
120 {
121 ULONG FileSize; // File size
122 ULONG FilePointer; // File pointer
123 PUINT32 FileFatChain; // File fat chain array
124 ULONG DriveNumber;
125 } FAT_FILE_INFO, * PFAT_FILE_INFO;
126
127
128
129 BOOL FatOpenVolume(ULONG DriveNumber, ULONG VolumeStartHead, ULONG VolumeStartTrack, ULONG VolumeStartSector, ULONG FatFileSystemType);
130 PVOID FatBufferDirectory(UINT32 DirectoryStartCluster, PUINT32 EntryCountPointer, BOOL RootDirectory);
131 BOOL FatSearchDirectoryBufferForFile(PVOID DirectoryBuffer, UINT32 EntryCount, PUCHAR FileName, PFAT_FILE_INFO FatFileInfoPointer);
132 BOOL FatLookupFile(PUCHAR FileName, PFAT_FILE_INFO FatFileInfoPointer);
133 ULONG FatGetNumPathParts(PUCHAR Path);
134 VOID FatGetFirstNameFromPath(PUCHAR Buffer, PUCHAR Path);
135 void FatParseShortFileName(PUCHAR Buffer, PDIRENTRY DirEntry);
136 BOOL FatGetFatEntry(UINT32 Cluster, PUINT32 ClusterPointer);
137 FILE* FatOpenFile(PUCHAR FileName);
138 UINT32 FatCountClustersInChain(UINT32 StartCluster);
139 PUINT32 FatGetClusterChainArray(UINT32 StartCluster);
140 BOOL FatReadCluster(ULONG ClusterNumber, PVOID Buffer);
141 BOOL FatReadClusterChain(ULONG StartClusterNumber, ULONG NumberOfClusters, PVOID Buffer);
142 BOOL FatReadPartialCluster(ULONG ClusterNumber, ULONG StartingOffset, ULONG Length, PVOID Buffer);
143 BOOL FatReadFile(FILE *FileHandle, ULONG BytesToRead, PULONG BytesRead, PVOID Buffer);
144 ULONG FatGetFileSize(FILE *FileHandle);
145 VOID FatSetFilePointer(FILE *FileHandle, ULONG NewFilePointer);
146 ULONG FatGetFilePointer(FILE *FileHandle);
147 BOOL FatReadVolumeSectors(ULONG DriveNumber, ULONG SectorNumber, ULONG SectorCount, PVOID Buffer);
148
149
150 #define EOF -1
151
152 #define ATTR_NORMAL 0x00
153 #define ATTR_READONLY 0x01
154 #define ATTR_HIDDEN 0x02
155 #define ATTR_SYSTEM 0x04
156 #define ATTR_VOLUMENAME 0x08
157 #define ATTR_DIRECTORY 0x10
158 #define ATTR_ARCHIVE 0x20
159 #define ATTR_LONG_NAME (ATTR_READONLY | ATTR_HIDDEN | ATTR_SYSTEM | ATTR_VOLUMENAME)
160
161 #define FAT12 1
162 #define FAT16 2
163 #define FAT32 3
164
165 #endif // #defined __FAT_H