/// <summary>
/// Compress data in-memory
/// </summary>
/// <param name="data"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
/// <param name="threads"></param>
/// <param name="level">0-9, default is 6, bigger number needs more time and produces smaller compressed data</param>
/// <returns></returns>
public static byte[] CompressBytes(byte[] data, int offset, int count, int threads = 1, int level = 6)
{
if (data == null)
{
throw new ArgumentNullException(nameof(data));
}
if (offset < 0)
{
throw new ArgumentOutOfRangeException(nameof(offset));
}
if (count < 0)
{
throw new ArgumentOutOfRangeException(nameof(count));
}
if (count + offset > data.Length)
{
throw new ArgumentOutOfRangeException(nameof(count), "offset+count > data.length");
}
if (level < 0 || level > 9)
{
throw new ArgumentOutOfRangeException(nameof(level));
}
var _lzma_stream = new lzma_stream();
var ret = CreateEncoder(_lzma_stream, threads, (uint)level);
if (ret == lzma_ret.LZMA_OK)
{
var compressed = CodeBuffer(_lzma_stream, data, offset, count);
Native.lzma_end(_lzma_stream);
return(compressed);
}
throw new Exception($"Can not create lzma stream: {ret}");
}
public static byte[] DecompressBytes(byte[] data, int offset, int count)
{
if (data == null)
{
throw new ArgumentNullException(nameof(data));
}
if (offset < 0)
{
throw new ArgumentOutOfRangeException(nameof(offset));
}
if (count < 0)
{
throw new ArgumentOutOfRangeException(nameof(count));
}
if (count + offset > data.Length)
{
throw new ArgumentOutOfRangeException(nameof(count), "offset+count > data.length");
}
var _lzma_stream = new lzma_stream();
var ret = Native.lzma_auto_decoder(_lzma_stream, ulong.MaxValue, Native.LZMA_CONCATENATED);
if (ret == lzma_ret.LZMA_OK)
{
var decompressed = CodeBuffer(_lzma_stream, data, offset, count);
Native.lzma_end(_lzma_stream);
return(decompressed);
}
throw new Exception($"Can not create lzma stream: {ret}");
}
internal static lzma_ret CreateEncoder(lzma_stream stream, int threads, uint preset)
{
// adjust thread numbers
if (threads > Environment.ProcessorCount)
{
Trace.TraceWarning("it's not reasonable to have more threads than processors");
threads = Environment.ProcessorCount;
}
if (threads == 1)
{
// single thread compress
return(Native.lzma_easy_encoder(stream, preset, lzma_check.LZMA_CHECK_CRC64));
}
else
{
// multi thread compress
var mt = new lzma_mt
{
threads = (uint)threads,
check = lzma_check.LZMA_CHECK_CRC64,
preset = preset,
};
return(Native.lzma_stream_encoder_mt(stream, mt));
}
}
internal static lzma_ret CreateEncoder(lzma_stream stream, int threads, uint preset)
{
// adjust thread numbers
if (threads > Environment.ProcessorCount)
{
Trace.TraceWarning("it's not reasonable to have more threads than processors");
threads = Environment.ProcessorCount;
}
if (threads == 1)
{
// single thread compress
return Native.lzma_easy_encoder(stream, preset, lzma_check.LZMA_CHECK_CRC64);
}
else
{
// multi thread compress
var mt = new lzma_mt
{
threads = (uint)threads,
check = lzma_check.LZMA_CHECK_CRC64,
preset = preset,
};
return Native.lzma_stream_encoder_mt(stream, mt);
}
}
/// <summary>
/// liblzma has provided lzma_stream_buffer_encode and lzma_stream_buffer_decode, but here I re-invent the wheel again...
/// </summary>
/// <param name="_lzma_stream"></param>
/// <param name="data"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
/// <returns></returns>
private static byte[] CodeBuffer(lzma_stream _lzma_stream, byte[] data, int offset, int count)
{
const int BUFSIZE = 4096;
var outStream = new MemoryStream(BUFSIZE);
var inbuf = Marshal.AllocHGlobal(BUFSIZE);
var outbuf = Marshal.AllocHGlobal(BUFSIZE);
try
{
var action = lzma_action.LZMA_RUN;
_lzma_stream.next_in = inbuf;
_lzma_stream.avail_in = UIntPtr.Zero;
_lzma_stream.next_out = outbuf;
_lzma_stream.avail_out = (UIntPtr)BUFSIZE;
int read_pos = offset;
while (true)
{
if (_lzma_stream.avail_in == UIntPtr.Zero)
{
if (read_pos < offset + count)
{
int bytesToProcess = Math.Min(BUFSIZE, offset + count - read_pos);
_lzma_stream.next_in = inbuf;
_lzma_stream.avail_in = (UIntPtr)bytesToProcess;
Marshal.Copy(data, read_pos, inbuf, bytesToProcess);
read_pos += bytesToProcess;
Trace.Assert(read_pos <= offset + count);
}
if (read_pos == offset + count)
action = lzma_action.LZMA_FINISH;
}
var ret = Native.lzma_code(_lzma_stream, action);
if (_lzma_stream.avail_out == UIntPtr.Zero || ret == lzma_ret.LZMA_STREAM_END)
{
int write_size = BUFSIZE - (int)(uint)_lzma_stream.avail_out;
var tmp = new byte[write_size];
Marshal.Copy(outbuf, tmp, 0, write_size);
outStream.Write(tmp, 0, write_size);
_lzma_stream.next_out = outbuf;
_lzma_stream.avail_out = (UIntPtr)BUFSIZE;
}
if (ret != lzma_ret.LZMA_OK)
{
if (ret == lzma_ret.LZMA_STREAM_END)
break;
throw new Exception($"lzma_code returns {ret}");
}
}
}
finally
{
Marshal.FreeHGlobal(inbuf);
Marshal.FreeHGlobal(outbuf);
}
return outStream.ToArray();
}
/// <summary>
/// liblzma has provided lzma_stream_buffer_encode and lzma_stream_buffer_decode, but here I re-invent the wheel again...
/// </summary>
/// <param name="_lzma_stream"></param>
/// <param name="data"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
/// <returns></returns>
private static byte[] CodeBuffer(lzma_stream _lzma_stream, byte[] data, int offset, int count)
{
const int BUFSIZE = 4096;
var outStream = new MemoryStream(BUFSIZE);
var inbuf = Marshal.AllocHGlobal(BUFSIZE);
var outbuf = Marshal.AllocHGlobal(BUFSIZE);
try
{
var action = lzma_action.LZMA_RUN;
_lzma_stream.next_in = inbuf;
_lzma_stream.avail_in = UIntPtr.Zero;
_lzma_stream.next_out = outbuf;
_lzma_stream.avail_out = (UIntPtr)BUFSIZE;
int read_pos = offset;
while (true)
{
if (_lzma_stream.avail_in == UIntPtr.Zero)
{
if (read_pos < offset + count)
{
int bytesToProcess = Math.Min(BUFSIZE, offset + count - read_pos);
_lzma_stream.next_in = inbuf;
_lzma_stream.avail_in = (UIntPtr)bytesToProcess;
Marshal.Copy(data, read_pos, inbuf, bytesToProcess);
read_pos += bytesToProcess;
Trace.Assert(read_pos <= offset + count);
}
if (read_pos == offset + count)
{
action = lzma_action.LZMA_FINISH;
}
}
var ret = Native.lzma_code(_lzma_stream, action);
if (_lzma_stream.avail_out == UIntPtr.Zero || ret == lzma_ret.LZMA_STREAM_END)
{
int write_size = BUFSIZE - (int)(uint)_lzma_stream.avail_out;
var tmp = new byte[write_size];
Marshal.Copy(outbuf, tmp, 0, write_size);
outStream.Write(tmp, 0, write_size);
_lzma_stream.next_out = outbuf;
_lzma_stream.avail_out = (UIntPtr)BUFSIZE;
}
if (ret != lzma_ret.LZMA_OK)
{
if (ret == lzma_ret.LZMA_STREAM_END)
{
break;
}
throw new Exception($"lzma_code returns {ret}");
}
}
}
finally
{
Marshal.FreeHGlobal(inbuf);
Marshal.FreeHGlobal(outbuf);
}
return(outStream.ToArray());
}
public static byte[] DecompressBytes(byte[] data, int offset, int count)
{
if (data == null) throw new ArgumentNullException(nameof(data));
if (offset < 0) throw new ArgumentOutOfRangeException(nameof(offset));
if (count < 0) throw new ArgumentOutOfRangeException(nameof(count));
if (count + offset > data.Length) throw new ArgumentOutOfRangeException(nameof(count), "offset+count > data.length");
var _lzma_stream = new lzma_stream();
var ret = Native.lzma_auto_decoder(_lzma_stream, ulong.MaxValue, Native.LZMA_CONCATENATED);
if (ret != lzma_ret.LZMA_OK)
throw new Exception($"Can not create lzma stream: {ret}");
return CodeBuffer(_lzma_stream, data, offset, count);
}
/// <summary>
/// Compress data in-memory
/// </summary>
/// <param name="data"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
/// <param name="threads"></param>
/// <param name="level">0-9, default is 6, bigger number needs more time and produces smaller compressed data</param>
/// <returns></returns>
public static byte[] CompressBytes(byte[] data, int offset, int count, int threads = 1, int level = 6)
{
if (data == null) throw new ArgumentNullException(nameof(data));
if (offset < 0) throw new ArgumentOutOfRangeException(nameof(offset));
if (count < 0) throw new ArgumentOutOfRangeException(nameof(count));
if (count + offset > data.Length) throw new ArgumentOutOfRangeException(nameof(count), "offset+count > data.length");
if (level < 0 || level > 9) throw new ArgumentOutOfRangeException(nameof(level));
var _lzma_stream = new lzma_stream();
var ret = CreateEncoder(_lzma_stream, threads, (uint)level);
if (ret != lzma_ret.LZMA_OK)
throw new Exception($"Can not create lzma stream: {ret}");
return CodeBuffer(_lzma_stream, data, offset, count);
}
