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@kingsznhone
kingsznhone committed Aug 9, 2024
1 parent 25f807b commit 2165a5b
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Showing 5 changed files with 362 additions and 58 deletions.
176 changes: 151 additions & 25 deletions src/FastLZMA2Net/CompressStream.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -2,7 +2,10 @@

namespace FastLZMA2Net
{
public class CompressStream : Stream, IDisposable
/// <summary>
/// Streaming Fast LZMA2 compress
/// </summary>
public class CompressStream : Stream
{
private readonly int bufferSize;
private byte[] outputBufferArray;
Expand All @@ -15,48 +18,76 @@ public class CompressStream : Stream, IDisposable
public override bool CanRead => _innerStream != null && _innerStream.CanRead;
public override bool CanWrite => false;
public override bool CanSeek => false;

/// <summary>
/// Can't determine decompressed data size
/// </summary>
public override long Length => throw new NotSupportedException();

public override long Position
{
get => throw new NotSupportedException();
set => throw new NotSupportedException();
}

/// <summary>
/// Compress Level [1..10]
/// </summary>
public int CompressLevel
{
get => (int)GetParameter(FL2Parameter.CompressionLevel);
set => SetParameter(FL2Parameter.CompressionLevel, (nuint)value);
}

/// <summary>
/// Levels 1..10 Setting to 1 switches to an alternate cLevel table.
/// </summary>
public int HighCompressLevel
{
get => (int)GetParameter(FL2Parameter.HighCompression);
set => SetParameter(FL2Parameter.HighCompression, (nuint)value);
}

/// <summary>
/// Dictionary size with FL2.DictSizeMin & FL2.DictSizeMax
/// </summary>
public int DictionarySize
{
get => (int)GetParameter(FL2Parameter.DictionarySize);
set => SetParameter(FL2Parameter.DictionarySize, (nuint)value);
}

/// <summary>
/// Match finder will resolve string matches up to this length.
/// If a longer match exists further back in the input, it will not be found.
/// Default = 42
/// </summary>
public int SearchDepth
{
get => (int)GetParameter(FL2Parameter.SearchDepth);
set => SetParameter(FL2Parameter.SearchDepth, (nuint)value);
}

/// <summary>
/// Only useful for strategies >= opt.
/// Length of match considered "good enough" to stop search.
/// Larger values make compression stronger and slower.
/// Default = 48
/// </summary>
public int FastLength
{
get => (int)GetParameter(FL2Parameter.FastLength);
set => SetParameter(FL2Parameter.FastLength, (nuint)value);
}

public CompressStream(Stream innerStream, uint nbThreads = 0, int outBufferSize = 64 * 1024 * 1024)
/// <summary>
/// Initialize streaming compress context
/// </summary>
/// <param name="dstStream">compressed data store</param>
/// <param name="nbThreads">thread use, auto = 0</param>
/// <param name="outBufferSize">Native interop buffer size, default = 64M</param>
/// <exception cref="FL2Exception"></exception>
public CompressStream(Stream dstStream, uint nbThreads = 0, int outBufferSize = 64 * 1024 * 1024)
{
bufferSize = outBufferSize;
_innerStream = innerStream;
_innerStream = dstStream;
_context = NativeMethods.FL2_createCStreamMt(nbThreads, 1);
var code = NativeMethods.FL2_initCStream(_context, 0);
if (FL2Exception.IsError(code))
Expand All @@ -75,33 +106,67 @@ public CompressStream(Stream innerStream, uint nbThreads = 0, int outBufferSize
};
}

/// <summary>
/// Append raw data to streaming, won't close compress stream
/// </summary>
/// <param name="buffer">Extra data</param>
/// <param name="offset">Start index in buffer</param>
/// <param name="count">How many bytes to append</param>
public void Append(byte[] buffer, int offset, int count)
{
Append(buffer.AsSpan(offset, count));
}

/// <summary>
/// Append raw data to streaming, won't close compress stream
/// </summary>
/// <param name="buffer">Extra data</param>
public void Append(ReadOnlySpan<byte> buffer)
{
CompressCore(buffer, true);
}

/// <summary>
/// Start compression and finish stream.
/// </summary>
/// <param name="buffer">Raw data</param>
/// <param name="offset">Start index in buffer</param>
/// <param name="count">How many bytes to append</param>
public override void Write(byte[] buffer, int offset, int count)
{
Write(buffer.AsSpan(offset, count));
}

/// <summary>
/// Start compression and finish stream.
/// </summary>
/// <param name="buffer">Raw data</param>
public override void Write(ReadOnlySpan<byte> buffer)
{
CompressCore(buffer, false);
}

/// <summary>
/// Start compression and finish stream asynchronized.
/// </summary>
/// <param name="buffer">Raw data</param>
/// <param name="offset">Start index in buffer</param>
/// <param name="count">How many bytes to append</param>
/// <param name="cancellationToken"></param>
/// <returns></returns>
public override async Task WriteAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
{
Memory<byte> bufferMemory = buffer.AsMemory(offset, count);
await new ValueTask<int>(CompressCore(bufferMemory.Span, false, cancellationToken)).ConfigureAwait(false);
return;
}

/// <summary>
/// Start compression and finish stream asynchronized.
/// </summary>
/// <param name="buffer">Raw data</param>
/// <param name="cancellationToken"></param>
/// <returns></returns>
public override async ValueTask WriteAsync(ReadOnlyMemory<byte> buffer, CancellationToken cancellationToken = default)
{
await new ValueTask<int>(CompressCore(buffer.Span, false, cancellationToken)).ConfigureAwait(false);
Expand All @@ -121,7 +186,7 @@ private unsafe int CompressCore(ReadOnlySpan<byte> buffer, bool Appending, Cance
};
nuint code;

//push source data& receive part of compressed data
//push source data & receive part of compressed data
do
{
outBuffer.pos = 0;
Expand Down Expand Up @@ -150,12 +215,9 @@ private unsafe int CompressCore(ReadOnlySpan<byte> buffer, bool Appending, Cance
code = NativeMethods.FL2_copyCStreamOutput(_context, ref outBuffer);
if (FL2Exception.IsError(code))
{
if (FL2Exception.IsError(code))
if (FL2Exception.GetErrorCode(code) != FL2ErrorCode.Buffer)
{
if (FL2Exception.GetErrorCode(code) != FL2ErrorCode.Buffer)
{
throw new FL2Exception(code);
}
throw new FL2Exception(code);
}
}
_innerStream.Write(outputBufferArray, 0, (int)outBuffer.pos);
Expand All @@ -166,20 +228,17 @@ private unsafe int CompressCore(ReadOnlySpan<byte> buffer, bool Appending, Cance
return 0;
}

// receive all remaining compressed data
// receive all remaining compressed data for safety
do
{
outBuffer.pos = 0;
//Returns 1 if input or output still exists in the CStream object, 0 if complete,
code = NativeMethods.FL2_flushStream(_context, ref outBuffer);
if (FL2Exception.IsError(code))
{
if (FL2Exception.IsError(code))
if (FL2Exception.GetErrorCode(code) != FL2ErrorCode.Buffer)
{
if (FL2Exception.GetErrorCode(code) != FL2ErrorCode.Buffer)
{
throw new FL2Exception(code);
}
throw new FL2Exception(code);
}
}
_innerStream.Write(outputBufferArray, 0, (int)outBuffer.pos);
Expand All @@ -190,7 +249,7 @@ private unsafe int CompressCore(ReadOnlySpan<byte> buffer, bool Appending, Cance
return 0;
}

//Write compress checksum
//Write compress checksum if not appending mode
if (!Appending)
{
code = NativeMethods.FL2_endStream(_context, ref outBuffer);
Expand All @@ -216,24 +275,77 @@ private unsafe int CompressCore(ReadOnlySpan<byte> buffer, bool Appending, Cance
return 0;
}

/// <summary>
/// Not support
/// </summary>
/// <param name="offset"></param>
/// <param name="origin"></param>
/// <returns></returns>
/// <exception cref="NotSupportedException"></exception>
public override long Seek(long offset, SeekOrigin origin) => throw new NotSupportedException();

/// <summary>
/// Not support
/// </summary>
/// <param name="value"></param>
/// <exception cref="NotSupportedException"></exception>
public override void SetLength(long value) => throw new NotSupportedException();

/// <summary>
/// Not support
/// </summary>
/// <param name="buffer"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
/// <returns></returns>
/// <exception cref="NotSupportedException"></exception>
public override int Read(byte[] buffer, int offset, int count) => throw new NotSupportedException();

/// <summary>
/// Not support
/// </summary>
/// <param name="buffer"></param>
/// <returns></returns>
/// <exception cref="NotSupportedException"></exception>
public override int Read(Span<byte> buffer) => throw new NotSupportedException();

/// <summary>
/// Not support
/// </summary>
/// <returns></returns>
/// <exception cref="NotSupportedException"></exception>
public override int ReadByte() => throw new NotSupportedException();

public override void Close() => Dispose(true);

/// <summary>
/// Not support
/// </summary>
/// <param name="buffer"></param>
/// <param name="offset"></param>
/// <param name="count"></param>
/// <param name="cancellationToken"></param>
/// <returns></returns>
/// <exception cref="NotSupportedException"></exception>
public override Task<int> ReadAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken = default)
=> throw new NotSupportedException();

=> throw new NotSupportedException();

/// <summary>
/// Not support
/// </summary>
/// <param name="buffer"></param>
/// <param name="cancellationToken"></param>
/// <returns></returns>
/// <exception cref="NotSupportedException"></exception>
public override ValueTask<int> ReadAsync(Memory<byte> buffer, CancellationToken cancellationToken = default)
=> throw new NotSupportedException();

/// <summary>
/// Close streaming progress
/// </summary>
public override void Close() => Dispose(true);

/// <summary>
/// Write Checksum in the end. finish compress progress.
/// </summary>
/// <exception cref="FL2Exception"></exception>
public override void Flush()
{
var code = NativeMethods.FL2_endStream(_context, ref outBuffer);
Expand All @@ -253,6 +365,14 @@ public override void Flush()
}
}


/// <summary>
/// Set detail compress parameter
/// </summary>
/// <param name="param"> Parameter Enum</param>
/// <param name="value"></param>
/// <returns>Error Code</returns>
/// <exception cref="FL2Exception"></exception>
public nuint SetParameter(FL2Parameter param, nuint value)
{
nuint code = NativeMethods.FL2_CStream_setParameter(_context, param, value);
Expand All @@ -263,6 +383,12 @@ public nuint SetParameter(FL2Parameter param, nuint value)
return code;
}

/// <summary>
/// Get detail compress parameter
/// </summary>
/// <param name="param"> Parameter Enum</param>
/// <returns>Parameter Value</returns>
/// <exception cref="FL2Exception"></exception>
public nuint GetParameter(FL2Parameter param)
{
var code = NativeMethods.FL2_CStream_getParameter(_context, param);
Expand All @@ -277,7 +403,7 @@ protected override void Dispose(bool disposing)
{
if (!disposed)
{
_innerStream.Flush();
Flush();
if (disposing)
{
outputBufferHandle.Free();
Expand Down
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