Initial commit.

2026-10-17 01:33:03 +08:00 · 2017-03-19 18:41:29 +01:00
parent bc50796f9d
commit 9b720d2325
70 changed files with 3487 additions and 0 deletions
@@ -0,0 +1,107 @@
+using System;
+using System.IO;
+using System.Text;
+using System.Threading.Tasks;
+using MQTTnet.Core.Channel;
+using MQTTnet.Core.Protocol;
+
+namespace MQTTnet.Core.Serializer
+{
+    public sealed class MqttPacketWriter : IDisposable
+    {
+        private readonly MemoryStream _buffer = new MemoryStream();
+
+        public void InjectFixedHeader(byte fixedHeader)
+        {
+            if (_buffer.Length == 0)
+            {
+                Write(fixedHeader);
+                Write(0);
+                return;
+            }
+
+            var remainingLength = (int)_buffer.Length;
+            using (var buffer = new MemoryStream())
+            {
+                _buffer.WriteTo(buffer);
+                _buffer.SetLength(0);
+
+                _buffer.WriteByte(fixedHeader);
+
+                // Alorithm taken from http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/os/mqtt-v3.1.1-os.html.
+                var x = remainingLength;
+                do
+                {
+                    var encodedByte = (byte)(x % 128);
+                    x = x / 128;
+                    if (x > 0)
+                    {
+                        encodedByte = (byte)(encodedByte | 128);
+                    }
+
+                    _buffer.WriteByte(encodedByte);
+                } while (x > 0);
+
+                buffer.Position = 0;
+                buffer.WriteTo(_buffer);
+            }
+        }
+
+        public void InjectFixedHeader(MqttControlPacketType packetType, byte flags = 0)
+        {
+            var fixedHeader = (byte)((byte)packetType << 4);
+            fixedHeader |= flags;
+            InjectFixedHeader(fixedHeader);
+        }
+
+        public void Write(byte value)
+        {
+            _buffer.WriteByte(value);
+        }
+
+        public void Write(char value)
+        {
+            _buffer.WriteByte((byte)value);
+        }
+
+        public void Write(ushort value)
+        {
+            var buffer = BitConverter.GetBytes(value);
+            _buffer.WriteByte(buffer[1]);
+            _buffer.WriteByte(buffer[0]);
+        }
+
+        public void Write(ByteWriter value)
+        {
+            _buffer.WriteByte(value.Value);
+        }
+
+        public void Write(byte[] value)
+        {
+            _buffer.Write(value, 0, value.Length);
+        }
+
+        public void WriteWithLengthPrefix(string value)
+        {
+            WriteWithLengthPrefix(Encoding.UTF8.GetBytes(value ?? string.Empty));
+        }
+
+        public void WriteWithLengthPrefix(byte[] value)
+        {
+            var length = (ushort)value.Length;
+
+            Write(length);
+            Write(value);
+        }
+
+        public void Dispose()
+        {
+            _buffer?.Dispose();
+        }
+
+        public async Task WriteToAsync(IMqttTransportChannel destination)
+        {
+            await destination.WriteAsync(_buffer.ToArray());
+        }
+    }
+}