/// <summary>
/// Initializes a new instance of the <see cref="DeflaterEngine"/> class.
/// </summary>
/// <param name="memoryAllocator">The memory allocator to use for buffer allocations.</param>
/// <param name="strategy">The deflate strategy to use.</param>
public DeflaterEngine(MemoryAllocator memoryAllocator, DeflateStrategy strategy)
{
this.huffman = new DeflaterHuffman(memoryAllocator);
this.Pending = this.huffman.Pending;
this.strategy = strategy;
// Create pinned pointers to the various buffers to allow indexing
// without bounds checks.
this.windowMemoryOwner = memoryAllocator.Allocate <byte>(2 * DeflaterConstants.WSIZE);
this.window = this.windowMemoryOwner.Memory;
this.windowMemoryHandle = this.window.Pin();
this.pinnedWindowPointer = (byte *)this.windowMemoryHandle.Pointer;
this.headMemoryOwner = memoryAllocator.Allocate <short>(DeflaterConstants.HASH_SIZE);
this.head = this.headMemoryOwner.Memory;
this.headMemoryHandle = this.head.Pin();
this.pinnedHeadPointer = (short *)this.headMemoryHandle.Pointer;
this.prevMemoryOwner = memoryAllocator.Allocate <short>(DeflaterConstants.WSIZE);
this.prev = this.prevMemoryOwner.Memory;
this.prevMemoryHandle = this.prev.Pin();
this.pinnedPrevPointer = (short *)this.prevMemoryHandle.Pointer;
// We start at index 1, to avoid an implementation deficiency, that
// we cannot build a repeat pattern at index 0.
this.blockStart = this.strstart = 1;
}
public void setStrat(EDeflateCompressStrategy strat)
{
DeflateStrategy newDeflateStrategy = DeflateStrategy.Default;
if (strat == EDeflateCompressStrategy.Filtered)
{
newDeflateStrategy = DeflateStrategy.Filtered;
}
else if (strat == EDeflateCompressStrategy.Huffman)
{
newDeflateStrategy = DeflateStrategy.HuffmanOnly;
}
else
{
newDeflateStrategy = DeflateStrategy.Default;
}
deflater.SetStrategy(newDeflateStrategy);
}
/// <summary>
/// Sets the compression strategy. Strategy is one of
/// DEFAULT_STRATEGY, HUFFMAN_ONLY and FILTERED. For the exact
/// position where the strategy is changed, the same as for
/// SetLevel() applies.
/// </summary>
/// <param name="strategy">
/// The new compression strategy.
/// </param>
public void SetStrategy(DeflateStrategy strategy)
{
engine.Strategy = strategy;
}
/// <summary>
/// Sets the compression strategy. Strategy is one of
/// DEFAULT_STRATEGY, HUFFMAN_ONLY and FILTERED. For the exact
/// position where the strategy is changed, the same as for
/// SetLevel() applies.
/// </summary>
/// <param name="strategy">
/// The new compression strategy.
/// </param>
public void SetStrategy(DeflateStrategy strategy)
{
engine.Strategy = strategy;
}
public void SetStrategy(DeflateStrategy stgy)
{
this.engine.Strategy = stgy;
}
