Migrate to Stream-less approach.

Frameworks/MQTTnet.NetStandard/Serializer/IMqttPacketSerializer.cs

@@ -1,5 +1,4 @@
 using System;
-using System.Collections.Generic;
 using System.IO;
 using MQTTnet.Packets;
 
@@ -11,6 +10,6 @@ namespace MQTTnet.Serializer
 
         ArraySegment<byte> Serialize(MqttBasePacket mqttPacket);
 
-        MqttBasePacket Deserialize(MqttPacketHeader header, MemoryStream body);
+        MqttBasePacket Deserialize(MqttPacketHeader header, Stream body);
     }
 }

Frameworks/MQTTnet.NetStandard/Serializer/MqttPacketReader.cs

@@ -1,9 +1,9 @@
 using System;
-using System.Collections.Generic;
 using System.IO;
 using System.Text;
 using System.Threading;
 using System.Threading.Tasks;
+using MQTTnet.Channel;
 using MQTTnet.Exceptions;
 using MQTTnet.Packets;
 using MQTTnet.Protocol;
@@ -13,7 +13,7 @@ namespace MQTTnet.Serializer
     public sealed class MqttPacketReader : BinaryReader
     {
         private readonly MqttPacketHeader _header;
-        
+
         public MqttPacketReader(MqttPacketHeader header, Stream bodyStream)
             : base(bodyStream, Encoding.UTF8, true)
         {
@@ -22,7 +22,7 @@ namespace MQTTnet.Serializer
 
         public bool EndOfRemainingData => BaseStream.Position == _header.BodyLength;
 
-        public static async Task<MqttPacketHeader> ReadHeaderAsync(Stream stream, CancellationToken cancellationToken)
+        public static async Task<MqttPacketHeader> ReadHeaderAsync(IMqttChannel stream, CancellationToken cancellationToken)
         {
             if (cancellationToken.IsCancellationRequested)
             {
@@ -33,7 +33,7 @@ namespace MQTTnet.Serializer
             // some large delay and thus the thread should be put back to the pool (await). So ReadByte()
             // is not an option here.
             var buffer = new byte[1];
-            var readCount = await stream.ReadAsync(buffer, 0, 1, cancellationToken).ConfigureAwait(false);
+            var readCount = await stream.ReadAsync(buffer, 0, buffer.Length, cancellationToken).ConfigureAwait(false);
             if (readCount <= 0)
             {
                 return null;
@@ -89,15 +89,14 @@ namespace MQTTnet.Serializer
             return ReadBytes(_header.BodyLength - (int)BaseStream.Position);
         }
 
-        private static async Task<int> ReadBodyLengthAsync(Stream stream, CancellationToken cancellationToken)
+        private static async Task<int> ReadBodyLengthAsync(IMqttChannel stream, CancellationToken cancellationToken)
         {
             // Alorithm taken from https://docs.oasis-open.org/mqtt/mqtt/v3.1.1/errata01/os/mqtt-v3.1.1-errata01-os-complete.html.
             var multiplier = 1;
             var value = 0;
-            byte encodedByte;
-
+            int encodedByte;
             var buffer = new byte[1];
-            var readBytes = new List<byte>();
+
             do
             {
                 if (cancellationToken.IsCancellationRequested)
@@ -112,12 +111,11 @@ namespace MQTTnet.Serializer
                 }
 
                 encodedByte = buffer[0];
-                readBytes.Add(encodedByte);
 
                 value += (byte)(encodedByte & 127) * multiplier;
                 if (multiplier > 128 * 128 * 128)
                 {
-                    throw new MqttProtocolViolationException($"Remaining length is invalid (Data={string.Join(",", readBytes)}).");
+                    throw new MqttProtocolViolationException("Remaining length is invalid.");
                 }
 
                 multiplier *= 128;

Frameworks/MQTTnet.NetStandard/Serializer/MqttPacketSerializer.cs

@@ -27,7 +27,7 @@ namespace MQTTnet.Serializer
 
                 var fixedHeader = SerializePacket(packet, writer);
 
-                var remainingLength = MqttPacketWriter.GetRemainingLength((int)stream.Length - 5);
+                var remainingLength = MqttPacketWriter.EncodeRemainingLength((int)stream.Length - 5);
 
                 var headerSize = remainingLength.Length + 1;
                 var headerOffset = 5 - headerSize;
@@ -47,7 +47,7 @@ namespace MQTTnet.Serializer
             }
         }
 
-        public MqttBasePacket Deserialize(MqttPacketHeader header, MemoryStream body)
+        public MqttBasePacket Deserialize(MqttPacketHeader header, Stream body)
         {
             if (header == null) throw new ArgumentNullException(nameof(header));
             if (body == null) throw new ArgumentNullException(nameof(body));
@@ -183,7 +183,7 @@ namespace MQTTnet.Serializer
 
             var topic = reader.ReadStringWithLengthPrefix();
 
-            ushort packetIdentifier = 0;
+            ushort? packetIdentifier = null;
             if (qualityOfServiceLevel > MqttQualityOfServiceLevel.AtMostOnce)
             {
                 packetIdentifier = reader.ReadUInt16();
@@ -191,12 +191,12 @@ namespace MQTTnet.Serializer
 
             var packet = new MqttPublishPacket
             {
+                PacketIdentifier = packetIdentifier,
                 Retain = retain,
-                QualityOfServiceLevel = qualityOfServiceLevel,
-                Dup = dup,
                 Topic = topic,
                 Payload = reader.ReadRemainingData(),
-                PacketIdentifier = packetIdentifier
+                QualityOfServiceLevel = qualityOfServiceLevel,
+                Dup = dup
             };
 
             return packet;

Frameworks/MQTTnet.NetStandard/Serializer/MqttPacketWriter.cs

@@ -56,7 +56,7 @@ namespace MQTTnet.Serializer
             Write(value);
         }
 
-        public static byte[] GetRemainingLength(int length)
+        public static byte[] EncodeRemainingLength(int length)
         {
             if (length <= 0)
             {
@@ -82,7 +82,8 @@ namespace MQTTnet.Serializer
                 offset++;
             } while (x > 0);
 
-            return bytes.Take(offset).ToArray();
+            Array.Resize(ref bytes, offset);
+            return bytes;
         }
     }
 }