public static Disk Read(byte[] source)
{
MemoryStream mem = new MemoryStream(source);
BinaryReader reader = new BinaryReader(mem);
Disk result = new Disk();
string id = new string(reader.ReadChars(8));
if (id == @"GCR-1541")
{
int trackCount;
int[] trackOffsetTable = new int[84];
int[] trackSpeedTable = new int[84];
reader.ReadByte(); //version
trackCount = reader.ReadByte();
reader.ReadInt16(); //max track size in bytes
for (int i = 0; i < 84; i++)
trackOffsetTable[i] = reader.ReadInt32();
for (int i = 0; i < 84; i++)
trackSpeedTable[i] = reader.ReadInt32();
for (int i = 0; i < 84; i++)
{
if (trackOffsetTable[i] > 0)
{
int trackLength;
byte[] trackData;
Track track = new Track();
mem.Position = trackOffsetTable[i];
trackLength = reader.ReadInt16();
trackData = reader.ReadBytes(trackLength);
track.bits = trackLength * 8;
track.data = trackData;
track.density = trackSpeedTable[i];
track.index = i;
result.tracks.Add(track);
}
}
}
result.valid = (result.tracks.Count > 0);
return result;
}
public static byte[] Write(Disk source)
{
return null;
}
public static Disk Read(byte[] source)
{
MemoryStream mem = new MemoryStream(source);
BinaryReader reader = new BinaryReader(mem);
Disk result = new Disk();
int trackCount = 0;
switch (source.Length)
{
case 174848: // 35 tracks no errors
trackCount = 35;
break;
case 175531: // 35 tracks with errors
trackCount = 35;
break;
case 196608: // 40 tracks no errors
trackCount = 40;
break;
case 197376: // 40 tracks with errors
trackCount = 40;
break;
}
for (int i = 0; i < trackCount; i++)
{
Track track = new Track();
int sectors = sectorsPerTrack[i];
MemoryStream trackMem = new MemoryStream();
for (int j = 0; j < sectors; j++)
{
int bitsWritten;
byte[] sectorData = reader.ReadBytes(256);
byte[] diskData = ConvertSectorToGCR(sectorData, (byte)j, (byte)i, (byte)0x00, (byte)0x00, out bitsWritten);
trackMem.Write(diskData, 0, diskData.Length);
}
track.density = densityTable[i];
// we pad the tracks with extra gap bytes to meet MNIB standards
while (trackMem.Length < standardTrackLengthBytes[track.density])
{
trackMem.WriteByte(0x55);
}
track.data = trackMem.ToArray();
track.bits = (int)trackMem.Length;
track.index = i;
result.tracks.Add(track);
trackMem.Dispose();
}
result.valid = (result.tracks.Count > 0);
return result;
}
public static byte[] Write(Disk source)
{
return(null);
}
