protected bool SetClusterEntryValue(uint cluster, uint nextcluster)
{
uint fatOffset = 0;
if (fatType == FATType.FAT12)
{
fatOffset = (cluster + (cluster / 2));
}
else if (fatType == FATType.FAT16)
{
fatOffset = cluster * 2;
}
else //if (type == FatType.FAT32)
{
fatOffset = cluster * 4;
}
uint sector = fatStart + (fatOffset / bytesPerSector);
uint sectorOffset = fatOffset % bytesPerSector;
uint nbrSectors = 1;
if ((fatType == FATType.FAT12) && (sectorOffset == bytesPerSector - 1))
{
nbrSectors = 2;
}
BinaryFormat fat = new BinaryFormat(partition.ReadBlock(sector, nbrSectors));
if (fatType == FATType.FAT12)
{
uint clustervalue = fat.GetUShort(sectorOffset);
if (cluster % 2 == 1)
{
clustervalue = ((clustervalue & 0xF) | (nextcluster << 4));
}
else
{
clustervalue = ((clustervalue & 0xf000) | (nextcluster));
}
fat.SetUShort(sectorOffset, (ushort)clustervalue);
}
else if (fatType == FATType.FAT16)
{
fat.SetUShort(sectorOffset, (ushort)nextcluster);
}
else //if (type == FatType.FAT32)
{
fat.SetUInt(sectorOffset, nextcluster);
}
partition.WriteBlock(sector, nbrSectors, fat.Data);
return(true);
}
/// <summary>
/// Identifies the drive.
/// </summary>
protected void IdentifyDrive()
{
byte drive = (byte)(((deviceHead & 0x10) != 0x10) ? 0 : 1);
byte d = (byte)('0' + drive + 1);
BinaryFormat data = new BinaryFormat(bufferData);
data.Fill(0, 0, 512);
// fixed drive and over 5Mb/sec
data.SetUShort(0x00, 0x140);
// Serial Number
data.Fill(0x0A * 2, d, 20);
data.SetByte(0x0A * 2, d);
// Firmware version
data.Fill(0x17 * 2, d, 8);
data.SetChar(0x17 * 2 + 0, '1');
data.SetChar(0x17 * 2 + 1, '.');
data.SetChar(0x17 * 2 + 2, '0');
// Model Number
data.Fill(0x1B * 2, d, 40);
data.SetChar(0x17 * 2 + 0, 'D');
data.SetChar(0x17 * 2 + 1, 'R');
data.SetChar(0x17 * 2 + 2, 'I');
data.SetChar(0x17 * 2 + 3, 'V');
data.SetChar(0x17 * 2 + 4, 'E');
data.SetByte(0x1B * 2 + 5, d);
// lba28
data.SetUInt(0x3C * 2, (uint)(driveFiles[drive].Length / 512));
commandStatus = (byte)((commandStatus | 0x08) & ~0x80); // Set DRQ (bit 3), clear BUSY (bit 7)
status = DeviceStatus.IdentifyDrive;
}
/// <summary>
/// Reads the LBA48.
/// </summary>
/// <param name="operation">The operation.</param>
/// <param name="drive">The drive.</param>
/// <param name="lba">The lba.</param>
/// <param name="data">The data.</param>
/// <param name="offset">The offset.</param>
/// <returns></returns>
protected bool ReadLBA48(SectorOperation operation, uint drive, uint lba, byte[] data, uint offset)
{
if (drive > MaximunDriveCount)
{
return(false);
}
FeaturePort.Write8(0);
FeaturePort.Write8(0);
SectorCountPort.Write8(0);
SectorCountPort.Write8(1);
LBALowPort.Write8((byte)((lba >> 24) & 0xFF));
LBALowPort.Write8((byte)(lba & 0xFF));
LBAMidPort.Write8((byte)((lba >> 32) & 0xFF));
LBAMidPort.Write8((byte)((lba >> 8) & 0xFF));
LBAHighPort.Write8((byte)((lba >> 40) & 0xFF));
LBAHighPort.Write8((byte)((lba >> 16) & 0xFF));
DeviceHeadPort.Write8((byte)(0x40 | (drive << 4)));
if (operation == SectorOperation.Write)
{
CommandPort.Write8(0x34);
}
else
{
CommandPort.Write8(0x24);
}
if (!WaitForReqisterReady())
{
return(false);
}
BinaryFormat sector = new BinaryFormat(data);
//TODO: Don't use PIO
if (operation == SectorOperation.Read)
{
for (uint index = 0; index < 256; index++)
{
sector.SetUShort(offset + (index * 2), DataPort.Read16());
}
}
else
{
for (uint index = 0; index < 256; index++)
{
DataPort.Write16(sector.GetUShort(offset + (index * 2)));
}
}
return(true);
}
public override void MakeDirectory(string DirName)
{
//TODO: Same Entry Exist exception.
FatFileLocation location = FindEntry(new FileSystem.Find.Empty(), FatCurrentDirectoryEntry);
uint FirstCluster = AllocateFirstCluster();
var xdata = new byte[512 * SectorsPerCluster];
this.IDevice.Read(location.DirectorySector, SectorsPerCluster, xdata);
BinaryFormat directory = new BinaryFormat(xdata);
directory.SetString(Entry.DOSName + location.DirectorySectorIndex * 32, " ", 11);
directory.SetString(Entry.DOSName + location.DirectorySectorIndex * 32, DirName);
directory.SetByte(Entry.FileAttributes + location.DirectorySectorIndex * 32, (byte)0x10);
directory.SetByte(Entry.Reserved + location.DirectorySectorIndex * 32, 0);
directory.SetByte(Entry.CreationTimeFine + location.DirectorySectorIndex * 32, 0);
directory.SetUShort(Entry.CreationTime + location.DirectorySectorIndex * 32, 0);
directory.SetUShort(Entry.CreationDate + location.DirectorySectorIndex * 32, 0);
directory.SetUShort(Entry.LastAccessDate + location.DirectorySectorIndex * 32, 0);
directory.SetUShort(Entry.LastModifiedTime + location.DirectorySectorIndex * 32, 0);
directory.SetUShort(Entry.LastModifiedDate + location.DirectorySectorIndex * 32, 0);
directory.SetUShort(Entry.FirstCluster + location.DirectorySectorIndex * 32, (ushort)FirstCluster);
directory.SetUInt(Entry.FileSize + location.DirectorySectorIndex * 32, 0);
this.IDevice.Write(location.DirectorySector, SectorsPerCluster, xdata);
FatFileLocation loc = FindEntry(new FileSystem.Find.Empty(), FirstCluster);
xdata = new byte[512 * SectorsPerCluster];
this.IDevice.Read(loc.DirectorySector, SectorsPerCluster, xdata);
directory = new BinaryFormat(xdata);
for (int i = 0; i < 2; i++)
{
directory.SetString(Entry.DOSName + loc.DirectorySectorIndex * 32, " ", 11);
if (i == 0)
{
directory.SetString(Entry.DOSName + loc.DirectorySectorIndex * 32, ".");
directory.SetUShort(Entry.FirstCluster + loc.DirectorySectorIndex * 32, (ushort)FirstCluster);
}
else
{
directory.SetString(Entry.DOSName + loc.DirectorySectorIndex * 32, "..");
directory.SetUShort(Entry.FirstCluster + loc.DirectorySectorIndex * 32, (ushort)FatCurrentDirectoryEntry);
}
directory.SetByte(Entry.FileAttributes + loc.DirectorySectorIndex * 32, (byte)0x10);
directory.SetByte(Entry.Reserved + loc.DirectorySectorIndex * 32, 0);
directory.SetByte(Entry.CreationTimeFine + loc.DirectorySectorIndex * 32, 0);
directory.SetUShort(Entry.CreationTime + loc.DirectorySectorIndex * 32, 0);
directory.SetUShort(Entry.CreationDate + loc.DirectorySectorIndex * 32, 0);
directory.SetUShort(Entry.LastAccessDate + loc.DirectorySectorIndex * 32, 0);
directory.SetUShort(Entry.LastModifiedTime + loc.DirectorySectorIndex * 32, 0);
directory.SetUShort(Entry.LastModifiedDate + loc.DirectorySectorIndex * 32, 0);
directory.SetUInt(Entry.FileSize + loc.DirectorySectorIndex * 32, 0);
loc.DirectorySectorIndex += 1;
}
this.IDevice.Write(loc.DirectorySector, SectorsPerCluster, xdata);
}
/// <summary>
/// Writes the master boot block.
/// </summary>
/// <returns></returns>
public bool Write()
{
if (!diskDevice.CanWrite)
{
return(false);
}
BinaryFormat masterboot = new BinaryFormat(new byte[512]);
masterboot.SetUInt(MBR.DiskSignature, diskSignature);
masterboot.SetUShort(MBR.MBRSignature, MBRConstant.MBRSignature);
if (code != null)
{
for (uint index = 0; ((index < MBRConstant.CodeAreaSize) && (index < code.Length)); index++)
{
masterboot.SetByte(index, code[index]);
}
}
for (uint index = 0; index < MaxMBRPartitions; index++)
{
if (Partitions[index].TotalBlocks != 0)
{
uint offset = MBR.FirstPartition + (index * 16);
masterboot.SetByte(offset + PartitionRecord.Status, (byte)(Partitions[index].Bootable ? 0x80 : 0x00));
masterboot.SetByte(offset + PartitionRecord.PartitionType, Partitions[index].PartitionType);
masterboot.SetUInt(offset + PartitionRecord.LBA, Partitions[index].StartLBA);
masterboot.SetUInt(offset + PartitionRecord.Sectors, Partitions[index].TotalBlocks);
DiskGeometry diskGeometry = new DiskGeometry();
diskGeometry.GuessGeometry(diskDevice.TotalBlocks);
CHS chsStart = new CHS();
CHS chsEnd = new CHS();
chsStart.SetCHS(diskGeometry, Partitions[index].StartLBA);
chsEnd.SetCHS(diskGeometry, Partitions[index].StartLBA + Partitions[index].TotalBlocks - 1);
masterboot.SetByte(offset + PartitionRecord.FirstCRS, chsStart.Head);
masterboot.SetByte(offset + PartitionRecord.FirstCRS + 1, (byte)((chsStart.Sector & 0x3F) | ((chsStart.Cylinder >> 8) & 0x03)));
masterboot.SetByte(offset + PartitionRecord.FirstCRS + 2, (byte)(chsStart.Cylinder & 0xFF));
masterboot.SetByte(offset + PartitionRecord.LastCRS, chsEnd.Head);
masterboot.SetByte(offset + PartitionRecord.LastCRS + 1, (byte)((chsEnd.Sector & 0x3F) | ((chsEnd.Cylinder >> 8) & 0x03)));
masterboot.SetByte(offset + PartitionRecord.LastCRS + 2, (byte)(chsEnd.Cylinder & 0xFF));
}
}
diskDevice.WriteBlock(0, 1, masterboot.Data);
return(true);
}
protected bool PerformLBA28(SectorOperation operation, uint driveNbr, uint lba, byte[] data, uint offset)
{
FeaturePort.Write8(0);
SectorCountPort.Write8(1);
LBALowPort.Write8((byte)(lba & 0xFF));
LBAMidPort.Write8((byte)((lba >> 8) & 0xFF));
LBAHighPort.Write8((byte)((lba >> 16) & 0xFF));
DeviceHeadPort.Write8((byte)(0xE0 | (driveNbr << 4) | ((lba >> 24) & 0x0F)));
if (operation == SectorOperation.Write)
{
CommandPort.Write8(IDECommand.WriteSectorsWithRetry);
}
else
{
CommandPort.Write8(IDECommand.ReadSectorsWithRetry);
}
if (!WaitForReqisterReady())
{
return(false);
}
BinaryFormat sector = new BinaryFormat(data);
//TODO: Don't use PIO
if (operation == SectorOperation.Read)
{
for (uint index = 0; index < 256; index++)
{
sector.SetUShort(offset + (index * 2), DataPort.Read16());
}
}
else
{
for (uint index = 0; index < 256; index++)
{
DataPort.Write16(sector.GetUShort(offset + (index * 2)));
}
}
return(true);
}
/// <summary>
/// Opens the specified drive NBR.
/// </summary>
/// <param name="drive">The drive NBR.</param>
/// <returns></returns>
public bool Open(uint drive)
{
if (drive > MaximunDriveCount)
{
return(false);
}
if (!driveInfo[drive].Present)
{
return(false);
}
if (drive == 0)
{
DeviceHeadPort.Write8(0xA0);
}
else
if (drive == 1)
{
DeviceHeadPort.Write8(0xB0);
}
else
{
return(false);
}
CommandPort.Write8(IDECommands.IdentifyDrive);
if (!WaitForReqisterReady())
{
return(false);
}
BinaryFormat info = new BinaryFormat(new byte[512]);
for (uint index = 0; index < 256; index++)
{
info.SetUShort(index * 2, DataPort.Read16());
}
driveInfo[drive].MaxLBA = info.GetUInt(IdentifyDrive.MaxLBA28);
return(true);
}
// doesn't work since uint should be uint64
//protected bool ReadLBA48 (SectorOperation operation, uint drive, uint lba, MemoryBlock memory)
//{
// FeaturePort.Write8 (0);
// FeaturePort.Write8 (0);
// SectorCountPort.Write8 (0);
// SectorCountPort.Write8 (1);
// LBALowPort.Write8 ((byte)((lba >> 24) & 0xFF));
// LBALowPort.Write8 ((byte)(lba & 0xFF));
// LBAMidPort.Write8 ((byte)((lba >> 32) & 0xFF));
// LBAMidPort.Write8 ((byte)((lba >> 8) & 0xFF));
// LBAHighPort.Write8 ((byte)((lba >> 40) & 0xFF));
// LBAHighPort.Write8 ((byte)((lba >> 16) & 0xFF));
// DeviceHeadPort.Write8 ((byte)(0x40 | (drive << 4)));
// if (operation == SectorOperation.Write)
// CommandPort.Write8 (0x34);
// else
// CommandPort.Write8 (0x24);
// if (!WaitForReqisterReady ())
// return false;
// //TODO: Don't use PIO
// if (operation == SectorOperation.Read) {
// for (uint index = 0; index < 256; index++)
// memory.SetUShort (index * 2, DataPort.Read16 ());
// }
// else {
// for (uint index = 0; index < 256; index++)
// DataPort.WriteUShort (memory.GetUShort (index * 2));
// }
// return true;
//}
public bool Open(uint driveNbr)
{
if (driveNbr == 0)
{
DeviceHeadPort.Write8(0xA0);
}
else
if (driveNbr == 1)
{
DeviceHeadPort.Write8(0xB0);
}
else
{
return(false);
}
CommandPort.Write8(IDECommand.IdentifyDrive);
if (!WaitForReqisterReady())
{
return(false);
}
BinaryFormat info = new BinaryFormat(new byte[512]);
for (uint index = 0; index < 256; index++)
{
info.SetUShort(index * 2, DataPort.Read16());
}
driveInfo[driveNbr].MaxLBA = info.GetUInt(IdentifyDrive.MaxLBA28);
// legacy info
driveInfo[driveNbr].Heads = info.GetUShort(IdentifyDrive.LogicalHeads);
driveInfo[driveNbr].Cylinders = info.GetUShort(IdentifyDrive.LogicalCylinders);
driveInfo[driveNbr].SectorsPerTrack = info.GetUShort(IdentifyDrive.LogicalSectors);
return(true);
}
public bool Format(FATSettings fatSettings)
{
if (!partition.CanWrite)
{
return(false);
}
this.fatType = fatSettings.FatType;
bytesPerSector = 512;
totalSectors = partition.BlockCount;
sectorsPerCluster = GetSectorsPerClusterByTotalSectors(fatType, totalSectors);
nbrFats = 2;
if (fatType == FATType.FAT32)
{
reservedSectors = 32;
rootEntries = 0;
}
else
{
reservedSectors = 1;
rootEntries = 512;
}
rootDirSectors = (((rootEntries * 32) + (bytesPerSector - 1)) / bytesPerSector);
fatStart = reservedSectors;
uint val1 = totalSectors - (reservedSectors + rootDirSectors);
uint val2 = (uint)((256 * sectorsPerCluster) + nbrFats);
if (fatType == FATType.FAT32)
{
val2 = val2 / 2;
}
uint sectorsperfat = (val1 + (val2 - 1)) / val2;
BinaryFormat bootSector = new BinaryFormat(512);
bootSector.SetUInt(BootSector.JumpInstruction, 0);
bootSector.SetString(BootSector.EOMName, "MSWIN4.1");
bootSector.SetUShort(BootSector.BytesPerSector, (ushort)bytesPerSector);
bootSector.SetByte(BootSector.SectorsPerCluster, (byte)sectorsPerCluster);
bootSector.SetUShort(BootSector.ReservedSectors, (ushort)reservedSectors);
bootSector.SetByte(BootSector.FatAllocationTables, nbrFats);
bootSector.SetUShort(BootSector.MaxRootDirEntries, (ushort)rootEntries);
if (totalSectors > 0xFFFF)
{
bootSector.SetUShort(BootSector.TotalSectors, 0);
bootSector.SetUInt(BootSector.FAT32_TotalSectors, totalClusters);
}
else
{
bootSector.SetUShort(BootSector.TotalSectors, (ushort)totalSectors);
bootSector.SetUInt(BootSector.FAT32_TotalSectors, 0);
}
bootSector.SetByte(BootSector.MediaDescriptor, 0xF8);
if (fatType == FATType.FAT32)
{
bootSector.SetUShort(BootSector.SectorsPerFAT, 0);
}
else
{
bootSector.SetUShort(BootSector.SectorsPerFAT, (ushort)sectorsperfat);
}
bootSector.SetUShort(BootSector.SectorsPerTrack, 0); ////FIXME
bootSector.SetUInt(BootSector.HiddenSectors, 0);
if (fatType != FATType.FAT32)
{
bootSector.SetByte(BootSector.PhysicalDriveNbr, 0x80);
bootSector.SetByte(BootSector.ReservedCurrentHead, 0);
bootSector.SetByte(BootSector.ExtendedBootSignature, 0x29);
bootSector.SetBytes(BootSector.IDSerialNumber, fatSettings.SerialID, 0, (uint)(fatSettings.SerialID.Length <= 4 ? fatSettings.SerialID.Length : 4));
bootSector.SetString(BootSector.VolumeLabel, " "); // 12 blank spaces
bootSector.SetString(BootSector.VolumeLabel, fatSettings.VolumeLabel, (uint)(fatSettings.VolumeLabel.Length <= 12 ? fatSettings.VolumeLabel.Length : 12));
bootSector.SetUShort(BootSector.BootSectorSignature, 0x55AA);
//BootSector.OSBootCode // TODO
}
if (fatType == FATType.FAT12)
{
bootSector.SetString(BootSector.FATType, "FAT12 ");
}
else if (fatType == FATType.FAT16)
{
bootSector.SetString(BootSector.FATType, "FAT16 ");
}
else // if (type == FatType.FAT32)
{
bootSector.SetString(BootSector.FATType, "FAT32 ");
}
if (fatType == FATType.FAT32)
{
bootSector.SetUInt(BootSector.FAT32_SectorPerFAT, sectorsperfat);
bootSector.SetByte(BootSector.FAT32_Flags, 0);
bootSector.SetUShort(BootSector.FAT32_Version, 0);
bootSector.SetUInt(BootSector.FAT32_ClusterNumberOfRoot, 2);
bootSector.SetUShort(BootSector.FAT32_SectorFSInformation, 1);
bootSector.SetUShort(BootSector.FAT32_SecondBootSector, 6);
//FAT32_Reserved1
bootSector.SetByte(BootSector.FAT32_PhysicalDriveNbr, 0x80);
bootSector.SetByte(BootSector.FAT32_Reserved2, 0);
bootSector.SetByte(BootSector.FAT32_ExtendedBootSignature, 0x29);
bootSector.SetBytes(BootSector.FAT32_IDSerialNumber, fatSettings.SerialID, 0, (uint)(fatSettings.SerialID.Length <= 4 ? fatSettings.SerialID.Length : 4));
bootSector.SetString(BootSector.FAT32_VolumeLabel, " "); // 12 blank spaces
bootSector.SetString(BootSector.FAT32_VolumeLabel, fatSettings.VolumeLabel, (uint)(fatSettings.VolumeLabel.Length <= 12 ? fatSettings.VolumeLabel.Length : 12));
bootSector.SetString(BootSector.FAT32_FATType, "FAT32 ");
//BootSector.OSBootCode // TODO
}
// Write Boot Sector
partition.WriteBlock(0, 1, bootSector.Data);
// Write backup Boot Sector
if (fatType == FATType.FAT32)
{
partition.WriteBlock(0, 1, bootSector.Data); // FIXME: wrong block #
}
// create FSInfo Structure
if (fatType == FATType.FAT32)
{
BinaryFormat infoSector = new BinaryFormat(512);
infoSector.SetUInt(FSInfo.FSI_LeadSignature, 0x41615252);
//FSInfo.FSI_Reserved1
infoSector.SetUInt(FSInfo.FSI_StructureSigature, 0x61417272);
infoSector.SetUInt(FSInfo.FSI_FreeCount, 0xFFFFFFFF);
infoSector.SetUInt(FSInfo.FSI_NextFree, 0xFFFFFFFF);
//FSInfo.FSI_Reserved2
bootSector.SetUInt(FSInfo.FSI_TrailSignature, 0xAA550000);
partition.WriteBlock(1, 1, infoSector.Data);
partition.WriteBlock(7, 1, infoSector.Data);
// create 2nd sector
BinaryFormat secondSector = new BinaryFormat(512);
secondSector.SetUInt((ushort)FSInfo.FSI_TrailSignature2, 0xAA55);
partition.WriteBlock(2, 1, secondSector.Data);
partition.WriteBlock(8, 1, secondSector.Data);
}
// create fats
/// TODO: incomplete
BinaryFormat emptyFat = new BinaryFormat(512);
// clear primary & secondary fats entries
for (uint i = fatStart; i < fatStart + 1; i++) //FIXME
{
partition.WriteBlock(i, 1, emptyFat.Data);
}
// first block is special
BinaryFormat firstFat = new BinaryFormat(512);
// TODO: incomplete
partition.WriteBlock(reservedSectors, 1, emptyFat.Data);
return(ReadBootSector());
}
public static void PatchSyslinux_3_72(PartitionDevice partitionDevice, FatFileSystem fat)
{
// Locate ldlinux.sys file for patching
string filename = "ldlinux.sys";
string name = (Path.GetFileNameWithoutExtension(filename) + Path.GetExtension(filename).PadRight(4).Substring(0, 4)).ToUpper();
var location = fat.FindEntry(name);
if (location.IsValid)
{
// Read boot sector
var bootSector = new BinaryFormat(partitionDevice.ReadBlock(0, 1));
// Set the first sector location of the file
bootSector.SetUInt(0x1F8, fat.GetSectorByCluster(location.FirstCluster));
// Change jump address
bootSector.SetUInt(0x01, 0x58);
// Write back patched boot sector
partitionDevice.WriteBlock(0, 1, bootSector.Data);
// Get the file size & number of sectors used
uint fileSize = fat.GetFileSize(location.DirectorySector, location.DirectorySectorIndex);
uint sectorCount = (fileSize + 511) >> 9;
uint[] sectors = new uint[65];
uint nsec = 0;
// Create list of the first 65 sectors of the file
for (uint cluster = location.FirstCluster; ((cluster != 0) & (nsec <= 64)); cluster = fat.GetNextCluster(cluster))
{
uint sec = fat.GetSectorByCluster(cluster);
for (uint s = 0; s < fat.SectorsPerCluster; s++)
{
sectors[nsec++] = sec + s;
}
}
// Read the first cluster of the file
var firstCluster = new BinaryFormat(fat.ReadCluster(location.FirstCluster));
uint patchArea = 0;
// Search for 0x3EB202FE (magic)
for (patchArea = 0; (firstCluster.GetUInt(patchArea) != 0x3EB202FE) && (patchArea < fat.ClusterSizeInBytes); patchArea += 4)
{
;
}
patchArea = patchArea + 8;
if (patchArea < fat.ClusterSizeInBytes)
{
// Set up the totals
firstCluster.SetUShort(patchArea, (ushort)(fileSize >> 2));
firstCluster.SetUShort(patchArea + 2, (ushort)(sectorCount - 1));
// Clear sector entries
firstCluster.Fill(patchArea + 8, 0, 64 * 4);
// Set sector entries
for (nsec = 0; nsec < 64; nsec++)
{
firstCluster.SetUInt(patchArea + 8 + (nsec * 4), sectors[nsec + 1]);
}
// Clear out checksum
firstCluster.SetUInt(patchArea + 4, 0);
// Write back the updated cluster
fat.WriteCluster(location.FirstCluster, firstCluster.Data);
// Re-Calculate checksum by opening the file
var file = new FatFileStream(fat, location);
uint csum = 0x3EB202FE;
for (uint index = 0; index < (file.Length >> 2); index++)
{
uint value = (uint)file.ReadByte() | ((uint)file.ReadByte() << 8) | ((uint)file.ReadByte() << 16) | ((uint)file.ReadByte() << 24);
csum -= value;
}
// Set the checksum
firstCluster.SetUInt(patchArea + 4, csum);
// Write patched cluster back to disk
fat.WriteCluster(location.FirstCluster, firstCluster.Data);
}
}
}
