Merge branch 'master' of https://github.com/oleg-st/ZstdSharp

Author: oleg-st

src/ZstdSharp.Test/ZstdNetSteamingTests.cs

@@ -425,6 +425,33 @@ public void RoundTrip_StreamingToStreaming_Stress([CombinatorialValues(true, fal
                 });
         }
 
+        [Fact]
+        public void RoundTrip_WrapperStreams()
+        {
+            using var compressor = new Compressor();
+            using var decompressor = new Decompressor();
+
+            using var dataStream = DataGenerator.GetLargeStream(DataFill.Sequential);
+
+            using var tempStream = new MemoryStream();
+            using (var compressionStream = new CompressionStream(tempStream, compressor))
+                dataStream.CopyTo(compressionStream);
+
+            var data = DataGenerator.GetLargeBuffer(DataFill.Sequential);
+            var compressed = compressor.Wrap(data).ToArray();
+
+            using var resultStream = new MemoryStream();
+            using (var decompressionStream = new DecompressionStream(new MemoryStream(compressed), decompressor))
+                decompressionStream.CopyTo(resultStream);
+
+            Assert.True(data.SequenceEqual(resultStream.ToArray()));
+
+            var resultBuffer = new byte[dataStream.Length];
+            Assert.Equal(dataStream.Length, decompressor.Unwrap(tempStream.ToArray(), resultBuffer, 0));
+
+            Assert.True(dataStream.ToArray().SequenceEqual(resultBuffer));
+        }
+
         private static byte[] TrainDict()
         {
             var trainingData = new byte[100][];

src/ZstdSharp/CompressionStream.cs

@@ -11,11 +11,18 @@ public class CompressionStream : Stream
     {
         private readonly Stream innerStream;
         private readonly byte[] outputBuffer;
+        private readonly bool preserveCompressor;
         private Compressor compressor;
         private ZSTD_outBuffer_s output;
 
         public CompressionStream(Stream stream, int level = Compressor.DefaultCompressionLevel,
             int bufferSize = 0)
+            : this(stream, new Compressor(level), bufferSize)
+        {
+            preserveCompressor = false;
+        }
+
+        public CompressionStream(Stream stream, Compressor compressor, int bufferSize = 0)
         {
             if (stream == null)
                 throw new ArgumentNullException(nameof(stream));
@@ -27,7 +34,8 @@ public CompressionStream(Stream stream, int level = Compressor.DefaultCompressio
                 throw new ArgumentOutOfRangeException(nameof(bufferSize));
 
             innerStream = stream;
-            compressor = new Compressor(level);
+            this.compressor = compressor;
+            preserveCompressor = true;
 
             var outputBufferSize =
                 bufferSize > 0 ? bufferSize : (int) Methods.ZSTD_CStreamOutSize().EnsureZstdSuccess();
@@ -93,12 +101,16 @@ protected override void Dispose(bool disposing)
 
         private void ReleaseUnmanagedResources()
         {
-            compressor.Dispose();
-            compressor = null;
+            if (!preserveCompressor)
+            {
+                compressor.Dispose();
+                compressor = null;
+            }
+
             ArrayPool<byte>.Shared.Return(outputBuffer);
         }
 
-        public override void Flush() 
+        public override void Flush()
             => WriteInternal(null, true);
 
         public override async Task FlushAsync(CancellationToken cancellationToken)
@@ -164,7 +176,7 @@ public async ValueTask WriteAsync(ReadOnlyMemory<byte> buffer,
             CancellationToken cancellationToken = default)
             => await WriteInternalAsync(buffer, false, cancellationToken).ConfigureAwait(false);
 #endif
-
+
         internal unsafe nuint CompressStream(ref ZSTD_inBuffer_s input, ReadOnlySpan<byte> inputBuffer,
             ZSTD_EndDirective directive)
         {

src/ZstdSharp/DecompressionStream.cs

@@ -12,11 +12,18 @@ public class DecompressionStream : Stream
         private readonly Stream innerStream;
         private readonly byte[] inputBuffer;
         private readonly int inputBufferSize;
+        private readonly bool preserveDecompressor;
         private Decompressor decompressor;
         private ZSTD_inBuffer_s input;
         private nuint lastDecompressResult = 0;
 
         public DecompressionStream(Stream stream, int bufferSize = 0)
+            : this(stream, new Decompressor(), bufferSize)
+        {
+            preserveDecompressor = false;
+        }
+
+        public DecompressionStream(Stream stream, Decompressor decompressor, int bufferSize = 0)
         {
             if (stream == null)
                 throw new ArgumentNullException(nameof(stream));
@@ -28,7 +35,8 @@ public DecompressionStream(Stream stream, int bufferSize = 0)
                 throw new ArgumentOutOfRangeException(nameof(bufferSize));
 
             innerStream = stream;
-            decompressor = new Decompressor();
+            this.decompressor = decompressor;
+            preserveDecompressor = true;
 
             inputBufferSize = bufferSize > 0 ? bufferSize : (int) Methods.ZSTD_CStreamInSize().EnsureZstdSuccess();
             inputBuffer = ArrayPool<byte>.Shared.Rent(inputBufferSize);
@@ -60,8 +68,12 @@ protected override void Dispose(bool disposing)
             if (decompressor == null)
                 return;
 
-            decompressor.Dispose();
-            decompressor = null;
+            if (!preserveDecompressor)
+            {
+                decompressor.Dispose();
+                decompressor = null;
+            }
+
             ArrayPool<byte>.Shared.Return(inputBuffer);
         }