/// <summary>
/// Writes the patched file into the output stream asynchronously.
/// This method is only asynchronous for the final step of writing the patched data into the output stream.
/// For large outputs, this may be beneficial.
/// </summary>
/// <returns></returns>
public async Task <(VCDiffResult result, long bytesWritten)> DecodeAsync()
{
if (!Decode_Init(out var bytesWritten, out var result, out var decodeAsync))
{
return(decodeAsync);
}
while (delta.CanRead)
{
//delta is streamed in order aka not random access
using var w = new WindowDecoder <TDeltaBuffer>(source.Length, delta, maxTargetFileSize);
if (w.Decode(this.IsSDCHFormat))
{
using var body = new BodyDecoder <TDeltaBuffer, TSourceBuffer, TDeltaBuffer>(w, source, delta, outputStream);
if (this.IsSDCHFormat && w.AddRunLength == 0 && w.AddressesForCopyLength == 0 && w.InstructionAndSizesLength > 0)
{
//interleaved
//decodedinterleave actually has an internal loop for waiting and streaming the incoming rest of the interleaved window
result = await body.DecodeInterleaveAsync();
if (result != VCDiffResult.SUCCESS && result != VCDiffResult.EOD)
{
return(result, bytesWritten);
}
bytesWritten += body.TotalBytesDecoded;
}
//technically add could be 0 if it is all copy instructions
//so do an or check on those two
else if (!this.IsSDCHFormat || (this.IsSDCHFormat && (w.AddRunLength > 0 || w.AddressesForCopyLength > 0) &&
w.InstructionAndSizesLength > 0))
{
//not interleaved
//expects the full window to be available
//in the stream
result = await body.DecodeAsync();
if (result != VCDiffResult.SUCCESS)
{
return(result, bytesWritten);
}
bytesWritten += body.TotalBytesDecoded;
}
else
{
//invalid file
return(VCDiffResult.ERROR, bytesWritten);
}
}
else
{
return((VCDiffResult)w.Result, bytesWritten);
}
}
return(result, bytesWritten);
}
/// <summary>
/// The main decoder loop for the data
/// </summary>
/// <param name="w">the window decoder</param>
/// <param name="source">The source dictionary data</param>
/// <param name="delta">The delta</param>
/// <param name="decodedTarget">the out stream</param>
/// <param name="customTable">custom table if any. Default is null.</param>
public BodyDecoder(WindowDecoder w, IByteBuffer source, IByteBuffer delta, Stream decodedTarget, CustomCodeTableDecoder?customTable = null)
{
if (customTable != null)
{
this.customTable = customTable;
addressCache = new AddressCache(customTable.NearSize, customTable.SameSize);
}
else
{
addressCache = new AddressCache();
}
window = w;
this.outputStream = decodedTarget;
this.source = source;
this.delta = delta;
this.targetData = new MemoryStream();
}
/// <summary>
/// The main decoder loop for the data
/// </summary>
/// <param name="w">the window decoder</param>
/// <param name="dictionary">the dictionary data</param>
/// <param name="target">the target data</param>
/// <param name="sout">the out stream</param>
/// <param name="customTable">custom table if any. Default is null.</param>
public BodyDecoder(WindowDecoder w, IByteBuffer dictionary, IByteBuffer target, ByteStreamWriter sout, CustomCodeTableDecoder customTable = null)
{
if (customTable != null)
{
this.customTable = customTable;
addressCache = new AddressCache((byte)customTable.NearSize, (byte)customTable.SameSize);
}
else
{
addressCache = new AddressCache();
}
window = w;
this.sout = sout;
this.dict = dictionary;
this.target = target;
targetData = new List <byte>();
}
/// <summary>
/// The main decoder loop for the data
/// </summary>
/// <param name="w">the window decoder</param>
/// <param name="source">The source dictionary data</param>
/// <param name="delta">The delta</param>
/// <param name="decodedTarget">the out stream</param>
/// <param name="customTable">custom table if any. Default is null.</param>
public BodyDecoder(WindowDecoder <TWindowDecoderByteBuffer> w, TSourceBuffer source, TDeltaBuffer delta, Stream decodedTarget, CustomCodeTableDecoder?customTable = null)
{
if (customTable != null)
{
this.customTable = customTable;
addressCache = new AddressCache(customTable.NearSize, customTable.SameSize);
}
else
{
addressCache = new AddressCache();
}
window = w;
this.outputStream = decodedTarget;
this.source = source;
this.delta = delta;
this.targetData = Pool.MemoryStreamManager.GetStream(nameof(BodyDecoder <TWindowDecoderByteBuffer, TSourceBuffer, TDeltaBuffer>), (int)w.TargetWindowLength);
}
/// <summary>
/// Use this after calling Start
/// Each time the decode is called it is expected
/// that at least 1 Window header is available in the stream
/// </summary>
/// <param name="bytesWritten">bytes decoded for all available windows</param>
/// <returns></returns>
public VCDiffResult Decode(out long bytesWritten)
{
if (!isStarted)
{
bytesWritten = 0;
return(VCDiffResult.ERRROR);
}
VCDiffResult result = VCDiffResult.SUCCESS;
bytesWritten = 0;
if (!delta.CanRead)
{
return(VCDiffResult.EOD);
}
while (delta.CanRead)
{
//delta is streamed in order aka not random access
WindowDecoder w = new WindowDecoder(dict.Length, delta);
if (w.Decode(googleVersion))
{
using (BodyDecoder body = new BodyDecoder(w, dict, delta, sout))
{
if (googleVersion && w.AddRunLength == 0 && w.AddressesForCopyLength == 0 && w.InstructionAndSizesLength > 0)
{
//interleaved
//decodedinterleave actually has an internal loop for waiting and streaming the incoming rest of the interleaved window
result = body.DecodeInterleave();
if (result != VCDiffResult.SUCCESS && result != VCDiffResult.EOD)
{
return(result);
}
bytesWritten += body.Decoded;
}
//technically add could be 0 if it is all copy instructions
//so do an or check on those two
else if (googleVersion && (w.AddRunLength > 0 || w.AddressesForCopyLength > 0) && w.InstructionAndSizesLength > 0)
{
//not interleaved
//expects the full window to be available
//in the stream
result = body.Decode();
if (result != VCDiffResult.SUCCESS)
{
return(result);
}
bytesWritten += body.Decoded;
}
else if (!googleVersion)
{
//not interleaved
//expects the full window to be available
//in the stream
result = body.Decode();
if (result != VCDiffResult.SUCCESS)
{
return(result);
}
bytesWritten += body.Decoded;
}
else
{
//invalid file
return(VCDiffResult.ERRROR);
}
}
}
else
{
return((VCDiffResult)w.Result);
}
}
return(result);
}
/// <summary>
/// Writes the patched file into the output stream.
/// </summary>
/// <param name="bytesWritten">Number of bytes written into the output stream.</param>
/// <returns></returns>
public VCDiffResult Decode(out long bytesWritten)
{
if (!this.IsInitialized)
{
var initializeResult = this.Initialize();
if (initializeResult != VCDiffResult.SUCCESS || !this.IsInitialized)
{
bytesWritten = 0;
return initializeResult;
}
}
VCDiffResult result = VCDiffResult.SUCCESS;
bytesWritten = 0;
if (!delta.CanRead) return VCDiffResult.EOD;
while (delta.CanRead)
{
//delta is streamed in order aka not random access
WindowDecoder w = new WindowDecoder(source.Length, delta);
if (w.Decode(this.IsSDCHFormat))
{
using BodyDecoder body = new BodyDecoder(w, source, delta, outputStream);
if (this.IsSDCHFormat && w.AddRunLength == 0 && w.AddressesForCopyLength == 0 && w.InstructionAndSizesLength > 0)
{
//interleaved
//decodedinterleave actually has an internal loop for waiting and streaming the incoming rest of the interleaved window
result = body.DecodeInterleave();
if (result != VCDiffResult.SUCCESS && result != VCDiffResult.EOD)
{
return result;
}
bytesWritten += body.TotalBytesDecoded;
}
//technically add could be 0 if it is all copy instructions
//so do an or check on those two
else if (!this.IsSDCHFormat || (this.IsSDCHFormat && (w.AddRunLength > 0 || w.AddressesForCopyLength > 0) && w.InstructionAndSizesLength > 0))
{
//not interleaved
//expects the full window to be available
//in the stream
result = body.Decode();
if (result != VCDiffResult.SUCCESS)
{
return result;
}
bytesWritten += body.TotalBytesDecoded;
}
else
{
//invalid file
return VCDiffResult.ERROR;
}
}
else
{
return (VCDiffResult)w.Result;
}
}
return result;
}
