/// <summary>
/// Creates a new decompression dictionary.
/// </summary>
/// <returns>
/// The IntPtr to the decompression dictionary.
/// </returns>
private IntPtr CreateDecompressionDictionary()
{
var alloc = GCHandle.Alloc(_dictionary, GCHandleType.Pinned);
try
{
var dictBuffer = Marshal.UnsafeAddrOfPinnedArrayElement(_dictionary, 0);
var dictSize = new UIntPtr((uint)_dictionary.Length);
return(Interop.ZSTD_createDDict(dictBuffer, dictSize));
}
finally
{
alloc.Free();
}
}
/// <summary>
/// Releases unmanaged resources.
/// </summary>
/// <param name="dispose"><c>true</c> to release both managed and unmanaged resources; <c>false</c> to release only unmanaged resources.</param>
// ReSharper disable once UnusedParameter.Local
private void Dispose(bool dispose)
{
if (_isDisposed == false)
{
_isDisposed = true;
if (_ddict != IntPtr.Zero)
{
Interop.ZSTD_freeDDict(_ddict);
_ddict = IntPtr.Zero;
}
foreach (KeyValuePair <int, IntPtr> kv in _cdicts.ToList())
{
Interop.ZSTD_freeCDict(kv.Value);
_cdicts.Remove(kv.Key);
}
}
}
/// <summary>
/// Releases unmanaged resources.
/// </summary>
/// <param name="dispose"><c>true</c> to release both managed and unmanaged resources; <c>false</c> to release only unmanaged resources.</param>
private void Dispose(bool dispose)
{
if (this.isDisposed == false)
{
this.isDisposed = true;
if (this.ddict != IntPtr.Zero)
{
Interop.ZSTD_freeDDict(this.ddict);
this.ddict = IntPtr.Zero;
}
foreach (var kv in this.cdicts.ToList())
{
Interop.ZSTD_freeCDict(kv.Value);
this.cdicts.Remove(kv.Key);
}
}
}
/// <summary>
/// Initializes a new instance of the <see cref="ZstandardStream"/> class by using the specified stream and compression mode, and optionally leaves the stream open.
/// </summary>
/// <param name="stream">The stream to compress.</param>
/// <param name="mode">One of the enumeration values that indicates whether to compress or decompress the stream.</param>
/// <param name="leaveOpen">true to leave the stream open after disposing the <see cref="ZstandardStream"/> object; otherwise, false.</param>
public ZstandardStream(Stream stream, CompressionMode mode, bool leaveOpen = false)
{
this.stream = stream ?? throw new ArgumentNullException(nameof(stream));
this.mode = mode;
this.leaveOpen = leaveOpen;
if (mode == CompressionMode.Compress)
{
this.zstreamInputSize = Interop.ZSTD_CStreamInSize().ToUInt32();
this.zstreamOutputSize = Interop.ZSTD_CStreamOutSize().ToUInt32();
this.zstream = Interop.ZSTD_createCStream();
this.data = arrayPool.Rent((int)this.zstreamOutputSize);
}
if (mode == CompressionMode.Decompress)
{
this.zstreamInputSize = Interop.ZSTD_DStreamInSize().ToUInt32();
this.zstreamOutputSize = Interop.ZSTD_DStreamOutSize().ToUInt32();
this.zstream = Interop.ZSTD_createDStream();
this.data = arrayPool.Rent((int)this.zstreamInputSize);
}
}
