use streams

Frameworks/MQTTnet.NetFramework/Implementations/MqttServerAdapter.cs

@@ -87,7 +87,9 @@ namespace MQTTnet.Implementations
                 try
                 {
                     var clientSocket = await Task.Factory.FromAsync(_defaultEndpointSocket.BeginAccept, _defaultEndpointSocket.EndAccept, null).ConfigureAwait(false);
-                    var clientAdapter = new MqttChannelCommunicationAdapter(new BufferedCommunicationChannel(new MqttTcpChannel(clientSocket, null)), new MqttPacketSerializer());
+
+                    var tcpChannel = new MqttTcpChannel(clientSocket, null);
+                    var clientAdapter = new MqttChannelCommunicationAdapter(tcpChannel, new MqttPacketSerializer());
                     ClientConnected?.Invoke(this, new MqttClientConnectedEventArgs(clientSocket.RemoteEndPoint.ToString(), clientAdapter));
                 }
                 catch (Exception exception) when (!(exception is ObjectDisposedException))
@@ -110,8 +112,9 @@ namespace MQTTnet.Implementations
 
                     var sslStream = new SslStream(new NetworkStream(clientSocket));
                     await sslStream.AuthenticateAsServerAsync(_tlsCertificate, false, SslProtocols.Tls12, false).ConfigureAwait(false);
-                    
-                    var clientAdapter = new MqttChannelCommunicationAdapter(new MqttTcpChannel(clientSocket, sslStream), new MqttPacketSerializer());
+
+                    var tcpChannel = new MqttTcpChannel(clientSocket, sslStream);
+                    var clientAdapter = new MqttChannelCommunicationAdapter(tcpChannel, new MqttPacketSerializer());
                     ClientConnected?.Invoke(this, new MqttClientConnectedEventArgs(clientSocket.RemoteEndPoint.ToString(), clientAdapter));
                 }
                 catch (Exception exception)

Frameworks/MQTTnet.NetFramework/Implementations/MqttTcpChannel.cs

@@ -17,6 +17,8 @@ namespace MQTTnet.Implementations
         private Socket _socket;
         private SslStream _sslStream;
 
+        public Stream Stream => _dataStream;
+
         /// <summary>
         /// called on client sockets are created in connect
         /// </summary>
@@ -79,45 +81,6 @@ namespace MQTTnet.Implementations
             }
         }
 
-        public async Task WriteAsync(byte[] buffer)
-        {
-            if (buffer == null) throw new ArgumentNullException(nameof(buffer));
-
-            try
-            {
-                await _dataStream.WriteAsync(buffer, 0, buffer.Length);
-            }
-            catch (SocketException exception)
-            {
-                throw new MqttCommunicationException(exception);
-            }
-        }
-
-        public async Task<ArraySegment<byte>> ReadAsync(int length, byte[] buffer)
-        {
-            try
-            {
-                var totalBytes = 0;
-
-                do
-                {
-                    var read = await _dataStream.ReadAsync(buffer, totalBytes, length - totalBytes).ConfigureAwait(false);
-                    if (read == 0)
-                    {
-                        throw new MqttCommunicationException(new SocketException((int)SocketError.Disconnecting));
-                    }
-
-                    totalBytes += read;
-                }
-                while (totalBytes < length);
-                return new ArraySegment<byte>(buffer, 0, length);
-            }
-            catch (SocketException exception)
-            {
-                throw new MqttCommunicationException(exception);
-            }
-        }
-
         public void Dispose()
         {
             _socket?.Dispose();

Frameworks/MQTTnet.NetFramework/Implementations/MqttWebSocketChannel.cs

@@ -2,6 +2,7 @@
 using MQTTnet.Core.Client;
 using MQTTnet.Core.Exceptions;
 using System;
+using System.IO;
 using System.Net.WebSockets;
 using System.Threading;
 using System.Threading.Tasks;
@@ -11,8 +12,8 @@ namespace MQTTnet.Implementations
     public sealed class MqttWebSocketChannel : IMqttCommunicationChannel, IDisposable
     {
         private ClientWebSocket _webSocket = new ClientWebSocket();
-        private int WebSocketBufferSize;
-        private int WebSocketBufferOffset;
+        
+        public Stream Stream { get; private set; }
 
         public async Task ConnectAsync(MqttClientOptions options)
         {
@@ -22,6 +23,8 @@ namespace MQTTnet.Implementations
             {
                 _webSocket = new ClientWebSocket();
                 await _webSocket.ConnectAsync(new Uri(options.Server), CancellationToken.None);
+
+                Stream = new WebSocketStream(_webSocket);
             }
             catch (WebSocketException exception)
             {
@@ -31,6 +34,7 @@ namespace MQTTnet.Implementations
 
         public Task DisconnectAsync()
         {
+            Stream = null;
             return _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, CancellationToken.None);
         }
 
@@ -38,62 +42,5 @@ namespace MQTTnet.Implementations
         {
             _webSocket?.Dispose();
         }
-
-        public async Task<ArraySegment<byte>> ReadAsync(int length, byte[] buffer)
-        {
-            await ReadToBufferAsync(length, buffer).ConfigureAwait(false);
-            
-            var result = new ArraySegment<byte>(buffer, WebSocketBufferOffset, length);
-            WebSocketBufferSize -= length;
-            WebSocketBufferOffset += length;
-            
-            return result;
-        }
-
-        private async Task ReadToBufferAsync(int length, byte[] buffer)
-        {
-            if (WebSocketBufferSize > 0)
-            {
-                return;
-            }
-
-            var offset = 0;
-            while (_webSocket.State == WebSocketState.Open && WebSocketBufferSize < length)
-            {
-                WebSocketReceiveResult response;
-                do
-                {
-                    response = await _webSocket.ReceiveAsync(new ArraySegment<byte>(buffer, offset, buffer.Length - offset), CancellationToken.None).ConfigureAwait(false);
-                    offset += response.Count;
-                } while (!response.EndOfMessage);
-
-                WebSocketBufferSize = response.Count;
-                if (response.MessageType == WebSocketMessageType.Close)
-                {
-                    await _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, CancellationToken.None).ConfigureAwait(false);
-                }
-            }
-        }
-
-        public async Task WriteAsync(byte[] buffer)
-        {
-            if (buffer == null) {
-                throw new ArgumentNullException(nameof(buffer));
-            }
-
-            try
-            {
-                await _webSocket.SendAsync(new ArraySegment<byte>(buffer), WebSocketMessageType.Binary, true, CancellationToken.None);
-            }
-            catch (WebSocketException exception)
-            {
-                throw new MqttCommunicationException(exception);
-            }
-        }
-
-        public int Peek()
-        {
-            return WebSocketBufferSize;
-        }
     }
 }

Frameworks/MQTTnet.NetFramework/Implementations/WebSocketStream.cs

@@ -0,0 +1,80 @@
+using System;
+using System.IO;
+using System.Net.WebSockets;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace MQTTnet.Implementations
+{
+    public class WebSocketStream : Stream
+    {
+        private readonly ClientWebSocket _webSocket;
+
+        public WebSocketStream( ClientWebSocket webSocket )
+        {
+            _webSocket = webSocket;
+        }
+
+        public override void Flush()
+        {
+        }
+
+        public override async Task<int> ReadAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
+        {
+            var currentOffset = offset;
+            var targetOffset = offset + count;
+            while (_webSocket.State == WebSocketState.Open && currentOffset < targetOffset)
+            {
+                var response = await _webSocket.ReceiveAsync(new ArraySegment<byte>(buffer, currentOffset, count), cancellationToken).ConfigureAwait(false);
+                currentOffset += response.Count;
+
+                if ( response.MessageType == WebSocketMessageType.Close )
+                {
+                    await _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, cancellationToken).ConfigureAwait(false);
+                }
+            }
+
+            return currentOffset - offset;
+        }
+
+        public override Task WriteAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
+        {
+            return _webSocket.SendAsync(new ArraySegment<byte>( buffer, offset, count ), WebSocketMessageType.Binary, true, cancellationToken);
+        }
+
+        public override int Read( byte[] buffer, int offset, int count )
+        {
+            return ReadAsync(buffer, offset, count).GetAwaiter().GetResult();
+        }
+
+        public override void Write(byte[] buffer, int offset, int count)
+        {
+            WriteAsync(buffer, offset, count).GetAwaiter().GetResult();
+        }
+
+        public override bool CanRead => true;
+        public override bool CanSeek => false;
+        public override bool CanWrite => true;
+
+        public override long Length
+        {
+            get { throw new NotSupportedException(); }
+        }
+
+        public override long Position
+        {
+            get { throw new NotSupportedException(); }
+            set { throw new NotSupportedException(); }
+        }
+
+        public override long Seek(long offset, SeekOrigin origin)
+        {
+            throw new NotSupportedException();
+        }
+
+        public override void SetLength(long value)
+        {
+            throw new NotSupportedException();
+        }
+    }
+}

Frameworks/MQTTnet.NetFramework/MQTTnet.NetFramework.csproj

@@ -101,6 +101,7 @@
   </ItemGroup>
   <ItemGroup>
     <Compile Include="Implementations\MqttWebSocketChannel.cs" />
+    <Compile Include="Implementations\WebSocketStream.cs" />
     <Compile Include="MqttClientFactory.cs" />
     <Compile Include="MqttServerFactory.cs" />
     <Compile Include="Implementations\MqttServerAdapter.cs" />

Frameworks/MQTTnet.NetFramework/MqttClientFactory.cs

@@ -22,7 +22,8 @@ namespace MQTTnet
             {
                 case MqttConnectionType.Tcp:
                 case MqttConnectionType.Tls:
-                    return new BufferedCommunicationChannel( new MqttTcpChannel() );
+                    var tcp = new MqttTcpChannel();
+                    return tcp;
                 case MqttConnectionType.Ws:
                 case MqttConnectionType.Wss:
                     return new MqttWebSocketChannel();

Frameworks/MQTTnet.NetStandard/Implementations/MqttTcpChannel.cs

@@ -17,6 +17,9 @@ namespace MQTTnet.Implementations
         private Socket _socket;
         private SslStream _sslStream;
 
+
+        public Stream Stream => _dataStream;
+
         /// <summary>
         /// called on client sockets are created in connect
         /// </summary>
@@ -78,45 +81,6 @@ namespace MQTTnet.Implementations
             }
         }
 
-        public async Task WriteAsync(byte[] buffer)
-        {
-            if (buffer == null) throw new ArgumentNullException(nameof(buffer));
-
-            try
-            {
-                await _dataStream.WriteAsync(buffer, 0, buffer.Length);
-            }
-            catch (SocketException exception)
-            {
-                throw new MqttCommunicationException(exception);
-            }
-        }
-
-        public async Task<ArraySegment<byte>> ReadAsync(int length, byte[] buffer)
-        {
-            try
-            {
-                var totalBytes = 0;
-
-                do
-                {
-                    var read = await _dataStream.ReadAsync(buffer, totalBytes, length - totalBytes).ConfigureAwait(false);
-                    if (read == 0)
-                    {
-                        throw new MqttCommunicationException(new SocketException((int)SocketError.Disconnecting));
-                    }
-
-                    totalBytes += read;
-                }
-                while (totalBytes < length);
-                return new ArraySegment<byte>(buffer, 0, length);
-            }
-            catch (SocketException exception)
-            {
-                throw new MqttCommunicationException(exception);
-            }
-        }
-
         public void Dispose()
         {
             _socket?.Dispose();

Frameworks/MQTTnet.NetStandard/Implementations/MqttWebSocketChannel.cs

@@ -2,6 +2,7 @@
 using MQTTnet.Core.Client;
 using MQTTnet.Core.Exceptions;
 using System;
+using System.IO;
 using System.Net.WebSockets;
 using System.Threading;
 using System.Threading.Tasks;
@@ -11,8 +12,8 @@ namespace MQTTnet.Implementations
     public sealed class MqttWebSocketChannel : IMqttCommunicationChannel, IDisposable
     {
         private ClientWebSocket _webSocket = new ClientWebSocket();
-        private int _bufferSize;
-        private int _bufferOffset;
+
+        public Stream Stream { get; private set; }
 
         public async Task ConnectAsync(MqttClientOptions options)
         {
@@ -22,6 +23,8 @@ namespace MQTTnet.Implementations
             {
                 _webSocket = new ClientWebSocket();
                 await _webSocket.ConnectAsync(new Uri(options.Server), CancellationToken.None);
+
+                Stream = new WebSocketStream(_webSocket);
             }
             catch (WebSocketException exception)
             {
@@ -31,6 +34,7 @@ namespace MQTTnet.Implementations
 
         public Task DisconnectAsync()
         {
+            Stream = null;
             return _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, CancellationToken.None);
         }
 
@@ -38,64 +42,5 @@ namespace MQTTnet.Implementations
         {
             _webSocket?.Dispose();
         }
-
-        public async Task<ArraySegment<byte>> ReadAsync(int length, byte[] buffer)
-        {
-            await ReadToBufferAsync(length, buffer).ConfigureAwait(false);
-
-            var result = new ArraySegment<byte>(buffer, _bufferOffset, length);
-            _bufferSize -= length;
-            _bufferOffset += length;
-
-            return result;
-        }
-
-        private async Task ReadToBufferAsync(int length, byte[] buffer)
-        {
-            if (_bufferSize > 0)
-            {
-                return;
-            }
-
-            var offset = 0;
-            while (_webSocket.State == WebSocketState.Open && _bufferSize < length)
-            {
-                WebSocketReceiveResult response;
-                do
-                {
-                    response = await _webSocket.ReceiveAsync(new ArraySegment<byte>(buffer, offset, buffer.Length - offset), CancellationToken.None).ConfigureAwait(false);
-                    offset += response.Count;
-                } while (!response.EndOfMessage);
-
-                _bufferSize = response.Count;
-
-                if (response.MessageType == WebSocketMessageType.Close)
-                {
-                    await _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, CancellationToken.None).ConfigureAwait(false);
-                }
-            }
-        }
-
-        public async Task WriteAsync(byte[] buffer)
-        {
-            if (buffer == null)
-            {
-                throw new ArgumentNullException(nameof(buffer));
-            }
-
-            try
-            {
-                await _webSocket.SendAsync(new ArraySegment<byte>(buffer), WebSocketMessageType.Binary, true, CancellationToken.None);
-            }
-            catch (WebSocketException exception)
-            {
-                throw new MqttCommunicationException(exception);
-            }
-        }
-
-        public int Peek()
-        {
-            return _bufferSize;
-        }
     }
 }

Frameworks/MQTTnet.NetStandard/Implementations/WebSocketStream.cs

@@ -0,0 +1,80 @@
+using System;
+using System.IO;
+using System.Net.WebSockets;
+using System.Threading;
+using System.Threading.Tasks;
+
+namespace MQTTnet.Implementations
+{
+    public class WebSocketStream : Stream
+    {
+        private readonly ClientWebSocket _webSocket;
+
+        public WebSocketStream(ClientWebSocket webSocket)
+        {
+            _webSocket = webSocket;
+        }
+
+        public override void Flush()
+        {
+        }
+
+        public override async Task<int> ReadAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
+        {
+            var currentOffset = offset;
+            var targetOffset = offset + count;
+            while ( _webSocket.State == WebSocketState.Open && currentOffset < targetOffset )
+            {
+                var response = await _webSocket.ReceiveAsync(new ArraySegment<byte>(buffer, currentOffset, count), cancellationToken).ConfigureAwait(false);
+                currentOffset += response.Count;
+
+                if ( response.MessageType == WebSocketMessageType.Close )
+                {
+                    await _webSocket.CloseAsync(WebSocketCloseStatus.NormalClosure, string.Empty, cancellationToken).ConfigureAwait(false);
+                }
+            }
+
+            return currentOffset - offset;
+        }
+
+        public override Task WriteAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
+        {
+            return _webSocket.SendAsync(new ArraySegment<byte>( buffer, offset, count ), WebSocketMessageType.Binary, true, cancellationToken);
+        }
+
+        public override int Read(byte[] buffer, int offset, int count)
+        {
+            return ReadAsync(buffer, offset, count).GetAwaiter().GetResult();
+        }
+
+        public override void Write(byte[] buffer, int offset, int count)
+        {
+            WriteAsync( buffer, offset, count ).GetAwaiter().GetResult();
+        }
+
+        public override bool CanRead => true;
+        public override bool CanSeek => false;
+        public override bool CanWrite => true;
+
+        public override long Length
+        {
+            get { throw new NotSupportedException(); }
+        }
+
+        public override long Position
+        {
+            get { throw new NotSupportedException(); }
+            set { throw new NotSupportedException(); }
+        }
+
+        public override long Seek(long offset, SeekOrigin origin)
+        {
+            throw new NotSupportedException();
+        }
+
+        public override void SetLength(long value)
+        {
+            throw new NotSupportedException();
+        }
+    }
+}

MQTTnet.Core/Channel/BufferedCommunicationChannel.cs

@@ -1,77 +0,0 @@
-using System.Threading.Tasks;
-using MQTTnet.Core.Client;
-using System;
-
-namespace MQTTnet.Core.Channel
-{
-    public class BufferedCommunicationChannel : IMqttCommunicationChannel
-    {
-        private readonly IMqttCommunicationChannel _inner;
-        private int _bufferSize;
-        private int _bufferOffset;
-
-        public BufferedCommunicationChannel(IMqttCommunicationChannel inner)
-        {
-            _inner = inner;
-        }
-
-        public Task ConnectAsync(MqttClientOptions options)
-        {
-            return _inner.ConnectAsync(options);
-        }
-
-        public Task DisconnectAsync()
-        {
-            return _inner.DisconnectAsync();
-        }
-
-        public int Peek()
-        {
-            return _inner.Peek();
-        }
-
-        public async Task<ArraySegment<byte>> ReadAsync(int length, byte[] buffer)
-        {
-            //read from buffer
-            if (_bufferSize > 0)
-            {
-                return ReadFomBuffer(length, buffer);
-            }
-
-            var available = _inner.Peek();
-            // if there are less or equal bytes available then requested then just read em
-            if (available <= length)
-            {
-                return await _inner.ReadAsync(length, buffer);
-            }
-
-            //if more bytes are available than requested do buffer them to reduce calls to network buffers
-            await WriteToBuffer(available, buffer).ConfigureAwait(false);
-            return ReadFomBuffer(length, buffer);
-        }
-
-        private async Task WriteToBuffer(int available, byte[] buffer)
-        {
-            await _inner.ReadAsync(available, buffer).ConfigureAwait(false);
-            _bufferSize = available;
-            _bufferOffset = 0;
-        }
-
-        private ArraySegment<byte> ReadFomBuffer(int length, byte[] buffer)
-        {
-            var result = new ArraySegment<byte>(buffer, _bufferOffset, length);
-            _bufferSize -= length;
-            _bufferOffset += length;
-
-            if (_bufferSize < 0)
-            {
-            }
-            return result;
-        }
-
-        public Task WriteAsync(byte[] buffer)
-        {
-            return _inner.WriteAsync(buffer);
-        }
-    }
-}

MQTTnet.Core/Channel/IMqttCommunicationChannel.cs

@@ -1,6 +1,6 @@
 using System.Threading.Tasks;
 using MQTTnet.Core.Client;
-using System;
+using System.IO;
 
 namespace MQTTnet.Core.Channel
 {
@@ -9,14 +9,7 @@ namespace MQTTnet.Core.Channel
         Task ConnectAsync(MqttClientOptions options);
 
         Task DisconnectAsync();
-
-        Task WriteAsync(byte[] buffer);
-
-        /// <summary>
-        /// get the currently available number of bytes without reading them
-        /// </summary>
-        int Peek();
-
-        Task<ArraySegment<byte>> ReadAsync(int length, byte[] buffer);
+        
+        Stream Stream { get; }
     }
 }

MQTTnet.Core/MQTTnet.Core.csproj

@@ -5,6 +5,7 @@
     <AssemblyName>MQTTnet.Core</AssemblyName>
     <RootNamespace>MQTTnet.Core</RootNamespace>
     <GeneratePackageOnBuild>False</GeneratePackageOnBuild>
+    <DebugType>Full</DebugType>
     <Description></Description>
     <Product></Product>
     <Company></Company>

MQTTnet.Core/Serializer/MqttPacketReader.cs

@@ -49,13 +49,13 @@ namespace MQTTnet.Core.Serializer
             return ReadBytes(_header.BodyLength - (int)BaseStream.Position);
         }
 
-        public static async Task<MqttPacketHeader> ReadHeaderFromSourceAsync(IMqttCommunicationChannel source, byte[] buffer)
+        public static MqttPacketHeader ReadHeaderFromSource(IMqttCommunicationChannel source)
         {
-            var fixedHeader = await ReadStreamByteAsync(source, buffer).ConfigureAwait(false);
+            var fixedHeader = (byte)source.Stream.ReadByte();
             var byteReader = new ByteReader(fixedHeader);
             byteReader.Read(4);
             var controlPacketType = (MqttControlPacketType)byteReader.Read(4);
-            var bodyLength = await ReadBodyLengthFromSourceAsync(source, buffer).ConfigureAwait(false);
+            var bodyLength = ReadBodyLengthFromSource(source);
 
             return new MqttPacketHeader()
             {
@@ -64,26 +64,8 @@ namespace MQTTnet.Core.Serializer
                 BodyLength = bodyLength
             };
         }
-
-        private static async Task<byte> ReadStreamByteAsync(IMqttCommunicationChannel source, byte[] readBuffer)
-        {
-            var result = await ReadFromSourceAsync(source, 1, readBuffer).ConfigureAwait(false);
-            return result.Array[result.Offset];
-        }
-
-        public static async Task<ArraySegment<byte>> ReadFromSourceAsync(IMqttCommunicationChannel source, int length, byte[] buffer)
-        {
-            try
-            {
-                return await source.ReadAsync(length, buffer);
-            }
-            catch (Exception exception)
-            {
-                throw new MqttCommunicationException(exception);
-            }
-        }
         
-        private static async Task<int> ReadBodyLengthFromSourceAsync(IMqttCommunicationChannel source, byte[] buffer)
+        private static int ReadBodyLengthFromSource(IMqttCommunicationChannel source)
         {
             // Alorithm taken from http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html.
             var multiplier = 1;
@@ -91,7 +73,7 @@ namespace MQTTnet.Core.Serializer
             byte encodedByte;
             do
             {
-                encodedByte = await ReadStreamByteAsync(source, buffer).ConfigureAwait(false);
+                encodedByte = (byte)source.Stream.ReadByte();
                 value += (encodedByte & 127) * multiplier;
                 multiplier *= 128;
                 if (multiplier > 128 * 128 * 128)

MQTTnet.Core/Serializer/MqttPacketSerializer.cs

@@ -17,7 +17,7 @@ namespace MQTTnet.Core.Serializer
         private static byte[] ProtocolVersionV310Name { get; } = Encoding.UTF8.GetBytes("MQIs");
 
         public MqttProtocolVersion ProtocolVersion { get; set; } = MqttProtocolVersion.V311;
-        private byte[] _readBuffer = new byte[BufferConstants.Size]; 
+        private Task _sendTask = Task.FromResult( 0 );
 
         public async Task SerializeAsync(MqttBasePacket packet, IMqttCommunicationChannel destination)
         {
@@ -32,12 +32,21 @@ namespace MQTTnet.Core.Serializer
 
                 var body = stream.ToArray();
                 MqttPacketWriter.BuildLengthHeader(body.Length, header);
-                
-                await destination.WriteAsync(header.ToArray()).ConfigureAwait(false);
-                await destination.WriteAsync(body).ConfigureAwait(false);
+                var headerArray = header.ToArray();
+                var writeBuffer = new byte[header.Count + body.Length];
+                Buffer.BlockCopy( headerArray, 0, writeBuffer, 0, headerArray.Length );
+                Buffer.BlockCopy( body, 0, writeBuffer, headerArray.Length, body.Length );
+
+                _sendTask = Send( writeBuffer, destination );
             }
         }
 
+        private async Task Send(byte[] buffer, IMqttCommunicationChannel destination )
+        {
+            await _sendTask.ConfigureAwait( false );
+            await destination.Stream.WriteAsync( buffer, 0, buffer.Length ).ConfigureAwait( false );
+        }
+
         private byte SerializePacket(MqttBasePacket packet, MqttPacketWriter writer)
         {
             if (packet is MqttConnectPacket connectPacket)
@@ -116,117 +125,127 @@ namespace MQTTnet.Core.Serializer
         public async Task<MqttBasePacket> DeserializeAsync(IMqttCommunicationChannel source)
         {
             if (source == null) throw new ArgumentNullException(nameof(source));
-
-            var header = await MqttPacketReader.ReadHeaderFromSourceAsync(source, _readBuffer).ConfigureAwait(false);
-
-            var body = await GetBody(source, header).ConfigureAwait(false);
-
-            using (var mqttPacketReader = new MqttPacketReader(body, header))
+            
+            var header = MqttPacketReader.ReadHeaderFromSource(source);
+            
+            MemoryStream body = null;
+            if ( header.BodyLength > 0 )
             {
-                switch (header.ControlPacketType)
+                var totalRead = 0;
+                var readBuffer = new byte[header.BodyLength];
+                do
                 {
-                    case MqttControlPacketType.Connect:
-                        {
-                            return DeserializeConnect(mqttPacketReader);
-                        }
+                    var read = await source.Stream.ReadAsync( readBuffer, totalRead, header.BodyLength - totalRead ).ConfigureAwait(false);
+                    totalRead += read;
+                } while ( totalRead < header.BodyLength );
+                body = new MemoryStream( readBuffer, 0, header.BodyLength );
+            }
+            else
+            {
+                body = new MemoryStream();
+            }
 
-                    case MqttControlPacketType.ConnAck:
-                        {
-                            return DeserializeConnAck(mqttPacketReader);
-                        }
-
-                    case MqttControlPacketType.Disconnect:
-                        {
-                            return new MqttDisconnectPacket();
-                        }
-
-                    case MqttControlPacketType.Publish:
-                        {
-                            return DeserializePublish(mqttPacketReader, header);
-                        }
-
-                    case MqttControlPacketType.PubAck:
-                        {
-                            return new MqttPubAckPacket
-                            {
-                                PacketIdentifier = mqttPacketReader.ReadUInt16()
-                            };
-                        }
-
-                    case MqttControlPacketType.PubRec:
-                        {
-                            return new MqttPubRecPacket
-                            {
-                                PacketIdentifier = mqttPacketReader.ReadUInt16()
-                            };
-                        }
-
-                    case MqttControlPacketType.PubRel:
-                        {
-                            return new MqttPubRelPacket
-                            {
-                                PacketIdentifier = mqttPacketReader.ReadUInt16()
-                            };
-                        }
-
-                    case MqttControlPacketType.PubComp:
-                        {
-                            return new MqttPubCompPacket
-                            {
-                                PacketIdentifier = mqttPacketReader.ReadUInt16()
-                            };
-                        }
-
-                    case MqttControlPacketType.PingReq:
-                        {
-                            return new MqttPingReqPacket();
-                        }
-
-                    case MqttControlPacketType.PingResp:
-                        {
-                            return new MqttPingRespPacket();
-                        }
-
-                    case MqttControlPacketType.Subscribe:
-                        {
-                            return DeserializeSubscribe(mqttPacketReader);
-                        }
-
-                    case MqttControlPacketType.SubAck:
-                        {
-                            return DeserializeSubAck(mqttPacketReader);
-                        }
-
-                    case MqttControlPacketType.Unsubscibe:
-                        {
-                            return DeserializeUnsubscribe(mqttPacketReader);
-                        }
-
-                    case MqttControlPacketType.UnsubAck:
-                        {
-                            return new MqttUnsubAckPacket
-                            {
-                                PacketIdentifier = mqttPacketReader.ReadUInt16()
-                            };
-                        }
-
-                    default:
-                        {
-                            throw new MqttProtocolViolationException($"Packet type ({(int)header.ControlPacketType}) not supported.");
-                        }
-                }
+            using (var reader = new MqttPacketReader(body, header))
+            {
+                return Deserialize( header, reader );
             }
         }
 
-        private async Task<MemoryStream> GetBody(IMqttCommunicationChannel source, MqttPacketHeader header)
+        private static MqttBasePacket Deserialize(MqttPacketHeader header, MqttPacketReader reader)
         {
-            if (header.BodyLength > 0)
+            switch (header.ControlPacketType)
             {
-                var segment = await MqttPacketReader.ReadFromSourceAsync(source, header.BodyLength, _readBuffer).ConfigureAwait(false);
-                return new MemoryStream(segment.Array, segment.Offset, segment.Count);
-            }
+                case MqttControlPacketType.Connect:
+                {
+                    return DeserializeConnect( reader );
+                }
 
-            return new MemoryStream();
+                case MqttControlPacketType.ConnAck:
+                {
+                    return DeserializeConnAck( reader );
+                }
+
+                case MqttControlPacketType.Disconnect:
+                {
+                    return new MqttDisconnectPacket();
+                }
+
+                case MqttControlPacketType.Publish:
+                {
+                    return DeserializePublish( reader, header );
+                }
+
+                case MqttControlPacketType.PubAck:
+                {
+                    return new MqttPubAckPacket
+                    {
+                        PacketIdentifier = reader.ReadUInt16()
+                    };
+                }
+
+                case MqttControlPacketType.PubRec:
+                {
+                    return new MqttPubRecPacket
+                    {
+                        PacketIdentifier = reader.ReadUInt16()
+                    };
+                }
+
+                case MqttControlPacketType.PubRel:
+                {
+                    return new MqttPubRelPacket
+                    {
+                        PacketIdentifier = reader.ReadUInt16()
+                    };
+                }
+
+                case MqttControlPacketType.PubComp:
+                {
+                    return new MqttPubCompPacket
+                    {
+                        PacketIdentifier = reader.ReadUInt16()
+                    };
+                }
+
+                case MqttControlPacketType.PingReq:
+                {
+                    return new MqttPingReqPacket();
+                }
+
+                case MqttControlPacketType.PingResp:
+                {
+                    return new MqttPingRespPacket();
+                }
+
+                case MqttControlPacketType.Subscribe:
+                {
+                    return DeserializeSubscribe( reader );
+                }
+
+                case MqttControlPacketType.SubAck:
+                {
+                    return DeserializeSubAck( reader );
+                }
+
+                case MqttControlPacketType.Unsubscibe:
+                {
+                    return DeserializeUnsubscribe( reader );
+                }
+
+                case MqttControlPacketType.UnsubAck:
+                {
+                    return new MqttUnsubAckPacket
+                    {
+                        PacketIdentifier = reader.ReadUInt16()
+                    };
+                }
+
+                default:
+                {
+                    throw new MqttProtocolViolationException(
+                        $"Packet type ({(int) header.ControlPacketType}) not supported." );
+                }
+            }
         }
 
         private static MqttBasePacket DeserializeUnsubscribe(MqttPacketReader reader)
@@ -268,7 +287,13 @@ namespace MQTTnet.Core.Serializer
             var qualityOfServiceLevel = (MqttQualityOfServiceLevel)fixedHeader.Read(2);
             var dup = fixedHeader.Read();
 
-            var topic = reader.ReadStringWithLengthPrefix();
+
+            var length = reader.ReadUInt16();
+            if (length != 5)
+            {
+                
+            }
+            var topic = Encoding.UTF8.GetString( reader.ReadBytes( length ), 0, length );
 
             ushort packetIdentifier = 0;
             if (qualityOfServiceLevel > MqttQualityOfServiceLevel.AtMostOnce)

Tests/MQTTnet.Core.Tests/MqttPacketSerializerTests.cs

@@ -391,6 +391,8 @@ namespace MQTTnet.Core.Tests
         {
             private readonly MemoryStream _stream = new MemoryStream();
 
+            public Stream Stream => _stream;
+
             public bool IsConnected { get; } = true;
 
             public TestChannel()
@@ -413,26 +415,10 @@ namespace MQTTnet.Core.Tests
                 return Task.FromResult(0);
             }
 
-            public Task WriteAsync(byte[] buffer)
-            {
-                return _stream.WriteAsync(buffer, 0, buffer.Length);
-            }
-
-            public async Task<ArraySegment<byte>> ReadAsync(int length, byte[] buffer)
-            {
-                await _stream.ReadAsync(buffer, 0, length);
-                return new ArraySegment<byte>(buffer, 0, length);
-            }
-
             public byte[] ToArray()
             {
                 return _stream.ToArray();
             }
-
-            public int Peek()
-            {
-                return (int)_stream.Length - (int)_stream.Position;
-            }
         }
 
         private static void SerializeAndCompare(MqttBasePacket packet, string expectedBase64Value, MqttProtocolVersion protocolVersion = MqttProtocolVersion.V311)