/// <summary>
/// Creates new instance of the <see cref="LZ4BlockDecoder"/> class.
/// </summary>
/// <param name="blockSize">Block size. Must be equal or greater to one used for compression.</param>
public LZ4BlockDecoder(int blockSize)
{
blockSize = LZ4MemoryHelper.RoundUp(Math.Max(blockSize, LZ4MemoryHelper.K1), LZ4MemoryHelper.K1);
_blockSize = blockSize;
_outputLength = _blockSize + 8;
_outputIndex = 0;
_outputBuffer = (byte *)LZ4MemoryHelper.Alloc(_outputLength + 8);
}
/// <summary>
/// Creates a new instance of the <see cref="LZ4Encoder"/> class.
/// </summary>
/// <param name="chaining">Needs to be `true` if using dependent blocks.</param>
/// <param name="blockSize">Block size.</param>
/// <param name="extraBlocks">Number of extra blocks.</param>
protected LZ4Encoder(bool chaining, int blockSize, int extraBlocks)
{
blockSize = LZ4MemoryHelper.RoundUp(Math.Max(blockSize, LZ4MemoryHelper.K1), LZ4MemoryHelper.K1);
extraBlocks = Math.Max(extraBlocks, 0);
int dictSize = chaining ? LZ4MemoryHelper.K64 : 0;
_blockSize = blockSize;
_inputLength = dictSize + (1 + extraBlocks) * blockSize + 8;
_inputIndex = _inputPointer = 0;
_inputBuffer = (byte *)LZ4MemoryHelper.Alloc(_inputLength + 8);
}
/// <summary>
/// Creates new instance of the <see cref="LZ4ChainDecoder"/> class.
/// </summary>
/// <param name="blockSize">Block size.</param>
/// <param name="extraBlocks">Number of extra blocks.</param>
public LZ4ChainDecoder(int blockSize, int extraBlocks)
{
blockSize = LZ4MemoryHelper.RoundUp(Math.Max(blockSize, LZ4MemoryHelper.K1), LZ4MemoryHelper.K1);
extraBlocks = Math.Max(extraBlocks, 0);
_blockSize = blockSize;
_outputLength = LZ4MemoryHelper.K64 + (1 + extraBlocks) * _blockSize + 8;
_outputIndex = 0;
_outputBuffer = (byte *)LZ4MemoryHelper.Alloc(_outputLength + 8);
_context = (LZ4Context *)LZ4MemoryHelper.AllocZero(sizeof(LZ4Context));
}
public uint FastStreamManual(int blockLength, int sourceLength)
{
sourceLength = LZ4MemoryHelper.RoundUp(sourceLength, blockLength);
var targetLength = 2 * sourceLength;
var context = (LZ4Engine.StreamT *)LZ4MemoryHelper.AllocZero(sizeof(LZ4Engine.StreamT));
var source = (byte *)LZ4MemoryHelper.Alloc(sourceLength);
var target = (byte *)LZ4MemoryHelper.Alloc(targetLength);
try
{
Lorem.Fill(source, sourceLength);
var sourceP = 0;
var targetP = 0;
while (sourceP < sourceLength && targetP < targetLength)
{
targetP += LZ4Engine64.CompressFastContinue(
context,
source + sourceP,
target + targetP,
Math.Min(blockLength, sourceLength - sourceP),
targetLength - targetP,
1);
sourceP += blockLength;
}
return(Tools.Adler32(target, targetP));
}
finally
{
LZ4MemoryHelper.Free(context);
LZ4MemoryHelper.Free(source);
LZ4MemoryHelper.Free(target);
}
}