tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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LzOutWindow.cs (2214B)

      1 // LzOutWindow.cs
      2 
      3 namespace SevenZip.Compression.LZ
      4 {
      5 public class OutWindow
      6 {
      7 	byte[] _buffer = null;
      8 	uint _pos;
      9 	uint _windowSize = 0;
     10 	uint _streamPos;
     11 	System.IO.Stream _stream;
     12 
     13 	public uint TrainSize = 0;
     14 
     15 	public void Create(uint windowSize)
     16 	{
     17 		if (_windowSize != windowSize)
     18 		{
     19 			// System.GC.Collect();
     20 			_buffer = new byte[windowSize];
     21 		}
     22 		_windowSize = windowSize;
     23 		_pos = 0;
     24 		_streamPos = 0;
     25 	}
     26 
     27 	public void Init(System.IO.Stream stream, bool solid)
     28 	{
     29 		ReleaseStream();
     30 		_stream = stream;
     31 		if (!solid)
     32 		{
     33 			_streamPos = 0;
     34 			_pos = 0;
     35 			TrainSize = 0;
     36 		}
     37 	}
     38 
     39 	public bool Train(System.IO.Stream stream)
     40 	{
     41 		long len = stream.Length;
     42 		uint size = (len < _windowSize) ? (uint)len : _windowSize;
     43 		TrainSize = size;
     44 		stream.Position = len - size;
     45 		_streamPos = _pos = 0;
     46 		while (size > 0)
     47 		{
     48 			uint curSize = _windowSize - _pos;
     49 			if (size < curSize)
     50 				curSize = size;
     51 			int numReadBytes = stream.Read(_buffer, (int)_pos, (int)curSize);
     52 			if (numReadBytes == 0)
     53 				return false;
     54 			size -= (uint)numReadBytes;
     55 			_pos += (uint)numReadBytes;
     56 			_streamPos += (uint)numReadBytes;
     57 			if (_pos == _windowSize)
     58 				_streamPos = _pos = 0;
     59 		}
     60 		return true;
     61 	}
     62 
     63 	public void ReleaseStream()
     64 	{
     65 		Flush();
     66 		_stream = null;
     67 	}
     68 
     69 	public void Flush()
     70 	{
     71 		uint size = _pos - _streamPos;
     72 		if (size == 0)
     73 			return;
     74 		_stream.Write(_buffer, (int)_streamPos, (int)size);
     75 		if (_pos >= _windowSize)
     76 			_pos = 0;
     77 		_streamPos = _pos;
     78 	}
     79 
     80 	public void CopyBlock(uint distance, uint len)
     81 	{
     82 		uint pos = _pos - distance - 1;
     83 		if (pos >= _windowSize)
     84 			pos += _windowSize;
     85 		for (; len > 0; len--)
     86 		{
     87 			if (pos >= _windowSize)
     88 				pos = 0;
     89 			_buffer[_pos++] = _buffer[pos++];
     90 			if (_pos >= _windowSize)
     91 				Flush();
     92 		}
     93 	}
     94 
     95 	public void PutByte(byte b)
     96 	{
     97 		_buffer[_pos++] = b;
     98 		if (_pos >= _windowSize)
     99 			Flush();
    100 	}
    101 
    102 	public byte GetByte(uint distance)
    103 	{
    104 		uint pos = _pos - distance - 1;
    105 		if (pos >= _windowSize)
    106 			pos += _windowSize;
    107 		return _buffer[pos];
    108 	}
    109 }
    110 }