| public Fill ( uint offset, byte value, uint length ) : void | ||
| offset | uint | The offset. |
| value | byte | The value. |
| length | uint | The length. |
| return | void | |
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(new Mosa.FileSystem.FAT.Find.WithName(name), 0);
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);
}
}
}
/// <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;
}
