private void CreateNewHash(FileHash newHash)
{
CloseCurrentHash();
fileHash = newHash;
fileMd5 = MD5.Create();
}
private void CloseCurrentHash()
{
if (fileHash == null)
{
return;
}
fileMd5.TransformFinalBlock(new byte[0], 0, 0);
fileHash.Hash = fileMd5.Hash;
fileMd5.Dispose();
fileMd5 = null;
fileHash = null;
}
public override void Write(byte[] buffer, int offset, int count)
{
if (count % Utilities.SectorSize != 0)
{
throw new NotSupportedException("Only write full sectors, and one sector at a time");
}
streamMd5.TransformBlock(buffer, offset, count, null, 0);
long parts = count / Utilities.SectorSize;
for (long i = 0; i < parts; i++)
{
FileHash currentHash = FindCurrentHash();
if ((fileHash != null && !fileHash.Equals(currentHash))) // Close the filehash
{
CloseCurrentHash();
}
if (currentHash != null)
{
if (fileHash == null) // Different hash!!!
{
CreateNewHash(currentHash);
}
if (fileHash != null)
{
// Now, find out how many bytes we have to write, only copy the required bytes.
// Probably, the rest of the buffer can be thrown away, unless count > Utilities.SectorSize
long posInFile = _position - (fileHash.StartSector * Utilities.SectorSize);
int amount = (int)Math.Min(Utilities.SectorSize, fileHash.Length - posInFile);
fileMd5.TransformBlock(buffer, offset, amount, null, 0);
}
}
offset += (int)Utilities.SectorSize;
_position += Utilities.SectorSize;
}
}
public bool Equals(FileHash fh)
{
return(fh != null && fh.StartSector == StartSector);
}