//closes the current block
private void closeBlock()
{
//close compression stream
compressionStream.Close();
//is this block empty? Then remove the new block header
if (this.decompressedByteCountWithinBlock == 0)
{
this.fileStream.SetLength(this.fileStream.Length - 16);
return;
}
//close block by filling the 8 byte block header (compressed block size)
//go back 8 bytes
this.fileStream.Seek(-8, SeekOrigin.Current);
//write "compressed block size"
byte[] buffer = BitConverter.GetBytes(this.mStream.Length);
this.fileStream.Write(buffer, 0, 8);
//go back to file head
this.fileStream.Seek(0, SeekOrigin.End);
//write memory stream to file
this.mStream.Position = 0;
this.mStream.CopyTo(this.fileStream);
}
// Called by the task when it is done with this writer, launches the async write
internal void Flush()
{
OutputSize += _bufferPos;
_writeTask = Task <uint> .Factory.StartNew(() => {
if (Compress)
{
_compressor.Write(_memBuffer, 0, (int)_bufferPos);
_compressor.Flush();
_compressor.Close();
_file.Flush();
}
else
{
_file.Write(_memBuffer, 0, (int)_bufferPos);
_file.Flush();
}
var size = (uint)_file.Position;
_compressor?.Dispose();
_file?.Dispose();
return(Compress ? size : 0);
});
}
/// <inheritdoc />
public byte[] Compress(byte[] source)
{
var output = new MemoryStream();
using (LZ4EncoderStream stream = LZ4Stream.Encode(output))
{
var reader = new MemoryStream(source);
reader.CopyTo(stream);
stream.Close();
return(output.ToArray());
}
}
