packet structure

MySolution/STcpHelper/Packet/ISTcpPacket.cs

@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace STcpHelper.Packet
+{
+    public interface ISTcpPacket
+    {
+        byte[] Serialize();
+    }
+}

MySolution/STcpHelper/Packet/PacketType.cs

@@ -0,0 +1,14 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace STcpHelper.Packet
+{
+    public enum PacketType
+    {
+        TEXT = 0,
+
+    }
+}

MySolution/STcpHelper/Packet/SBufferHelper.cs

@@ -0,0 +1,27 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace STcpHelper.Packet
+{
+    static class SBufferHelper
+    {
+        public static byte[] GetBuffer(int size, params byte[][] args)
+        {
+            byte[] bytes = new byte[size];
+            int cursor = 0;
+
+            for (int i = 0; i < args.Length; i++)
+            {
+                byte[] data = args[i];
+
+                Array.Copy(data, 0, bytes, cursor, data.Length);
+                cursor += data.Length;
+            }
+
+            return bytes;
+        }
+    }
+}

MySolution/STcpHelper/Packet/STcpPacketHeader.cs

@@ -0,0 +1,42 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace STcpHelper.Packet
+{
+    /// <summary>
+    /// 4byte header
+    /// </summary>
+    public class STcpPacketHeader : ISTcpPacket
+    {
+        public PacketType Type { get; private set; }
+        public short DataLength { get; private set; }
+
+        public STcpPacketHeader(PacketType type, int dataLength)
+        {
+            Type = type;
+            DataLength = (short)dataLength;
+        }
+
+        public STcpPacketHeader(byte[] buffer)
+        {
+            int cursor = 0;
+            this.Type = (PacketType)IPAddress.NetworkToHostOrder(BitConverter.ToInt16(buffer, cursor));
+            cursor += 2;
+
+            this.DataLength = IPAddress.NetworkToHostOrder(BitConverter.ToInt16(buffer, cursor));
+        }
+
+        // [2bytes Type][2bytes Size]
+        public byte[] Serialize()
+        {
+            byte[] type = BitConverter.GetBytes(IPAddress.HostToNetworkOrder((short)this.Type));
+            byte[] size = BitConverter.GetBytes(IPAddress.HostToNetworkOrder(this.DataLength));
+
+            return SBufferHelper.GetBuffer(type.Length + size.Length, type, size);
+        }
+    }
+}

MySolution/STcpHelper/Packet/STcpTextPacket.cs

@@ -0,0 +1,40 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Net;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace STcpHelper.Packet
+{
+    public class STcpTextPacket : ISTcpPacket
+    {
+        public string Text { get; private set; }
+
+        public STcpTextPacket(string text)
+        {
+            this.Text = text;
+        }
+
+        public STcpTextPacket(byte[] dataBuffer)
+        {
+            int cursor = 0;
+            short textSize = IPAddress.NetworkToHostOrder(BitConverter.ToInt16(dataBuffer, cursor));
+            cursor += sizeof(short);
+
+            this.Text = Encoding.UTF8.GetString(dataBuffer, cursor, textSize);
+        }
+
+        public byte[] Serialize()
+        {
+            byte[] text = Encoding.UTF8.GetBytes(Text);
+            byte[] textSize = BitConverter.GetBytes(IPAddress.HostToNetworkOrder((short)text.Length));
+
+            // 4byte header
+            STcpPacketHeader header = new STcpPacketHeader(PacketType.TEXT, text.Length + textSize.Length);
+
+            // [2bytes text size][n bytes text]
+            return SBufferHelper.GetBuffer(4 + textSize.Length + text.Length, header.Serialize(), textSize, text);
+        }
+    }
+}

MySolution/STcpHelper/STcpClient.cs

@@ -1,5 +1,7 @@
-using System;
+using STcpHelper.Packet;
+using System;
 using System.Collections.Generic;
+using System.IO;
 using System.Linq;
 using System.Net.Sockets;
 using System.Text;
@@ -17,6 +19,9 @@ namespace STcpHelper
         private TcpClient _client;
         private NetworkStream _stream;
 
+        private readonly int HEADER_SIZE = 4;
+        private readonly int BUFFER_SIZE = 1024;
+
         public async void Connect(string ip, int port)
         {
             try
@@ -28,20 +33,35 @@ namespace STcpHelper
                 _cts = new CancellationTokenSource();
                 _ = Task.Run(async () =>
                 {
-                    byte[] readBuffer = new byte[1024];
+                    byte[] headerBuffer = new byte[HEADER_SIZE];
+                    byte[] dataBuffer = new byte[BUFFER_SIZE];
                     while (true)
                     {
                         Thread.Sleep(50);
                         if (_cts.IsCancellationRequested)
                             break;
 
-                        int bytesRead = await this._stream.ReadAsync(readBuffer);
-                        if (bytesRead < 1)
-                            break;
+                        int headerBytesRead = await _stream.ReadAsync(headerBuffer, 0, HEADER_SIZE);
+                        if (headerBytesRead != 4)
+                        {
+                            WriteError(new Exception("Cannot read header"));
+                            return;
+                        }
+
+                        STcpPacketHeader header = new STcpPacketHeader(headerBuffer);
+                        short dataSize = header.DataLength;
+                        int totalRecv = 0;
+                        while (totalRecv < dataSize)
+                        {
+                            int dataBytesRead = await _stream.ReadAsync(dataBuffer, totalRecv, dataSize - totalRecv);
+                            totalRecv += dataBytesRead;
+                        }
 
-                        string message = Encoding.UTF8.GetString(readBuffer, 0, bytesRead);
-                        if (this.MessageCallback != null)
-                            this.MessageCallback(this, message);
+                        if (header.Type == PacketType.TEXT)
+                        {
+                            STcpTextPacket packet = new STcpTextPacket(dataBuffer);
+                            WriteMessage(packet.Text);
+                        }
                     }
                 }, _cts.Token);
             }
@@ -51,11 +71,17 @@ namespace STcpHelper
             }
         }
 
+        private byte[] MakeTextPacket(string text)
+        {
+            STcpTextPacket packet = new STcpTextPacket(text);
+            return packet.Serialize();
+        }
+
         public async void SendMessage(string message)
         {
             try
             {
-                byte[] sendBytes = Encoding.UTF8.GetBytes(message);
+                byte[] sendBytes = MakeTextPacket(message);
                 await _stream.WriteAsync(sendBytes);
             }
             catch (Exception ex)

MySolution/STcpHelper/STcpHelper.csproj

@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <TargetFramework>net6.0</TargetFramework>

MySolution/STcpHelper/STcpServer.cs

@@ -1,4 +1,5 @@
-using System.Net;
+using STcpHelper.Packet;
+using System.Net;
 using System.Net.Sockets;
 using System.Text;
 
@@ -10,6 +11,7 @@ namespace STcpHelper
 
         private List<TcpClient> _clients;
 
+        private readonly int HEADER_SIZE = 4;
         private readonly int BUFFER_SIZE;
         private int _port;
 
@@ -47,17 +49,37 @@ namespace STcpHelper
                 {
                     using (NetworkStream stream = client.GetStream())
                     {
-                        byte[] buffer = new byte[BUFFER_SIZE];
-                        int bytesRead;
+                        byte[] headerBuffer = new byte[HEADER_SIZE];
+                        byte[] dataBuffer = new byte[BUFFER_SIZE];
                         try
                         {
-                            while ((bytesRead = await stream.ReadAsync(buffer, 0, BUFFER_SIZE)) > 0)
+                            while (true)
                             {
-                                string message = Encoding.UTF8.GetString(buffer, 0, bytesRead);
-                                WriteMessage($"[{client.Client.RemoteEndPoint.ToString()}] {message}");
-
-                                // Broadcast
-                                BroadcastMessage(message, client);
+                                int headerBytesRead = await stream.ReadAsync(headerBuffer, 0, HEADER_SIZE);
+                                if (headerBytesRead != 4)
+                                {
+                                    WriteError(new Exception("Cannot read header"));
+                                    return;
+                                }
+
+                                STcpPacketHeader header = new STcpPacketHeader(headerBuffer);
+                                short dataSize = header.DataLength;
+                                int totalRecv = 0;
+                                while (totalRecv < dataSize)
+                                {
+                                    int dataBytesRead = await stream.ReadAsync(dataBuffer, totalRecv, dataSize - totalRecv);
+                                    totalRecv += dataBytesRead;
+                                }
+
+                                if (header.Type == PacketType.TEXT)
+                                {
+                                    STcpTextPacket packet = new STcpTextPacket(dataBuffer);
+                                    WriteMessage($"[{client.Client.RemoteEndPoint.ToString()}] Type: {header.Type.ToString()}");
+
+                                    // Broadcast
+                                    BroadcastMessage(packet.Text, client);
+
+                                }
 
                                 if (!IsClientConnected(client))
                                     break;
@@ -81,9 +103,15 @@ namespace STcpHelper
             _cts.Cancel();
         }
 
+        private byte[] MakeTextPacket(string text)
+        {
+            STcpTextPacket packet = new STcpTextPacket(text);
+            return packet.Serialize();
+        }
+
         private void BroadcastMessage(string message, TcpClient sender)
         {
-            byte[] resonseByte = Encoding.UTF8.GetBytes(message);
+            byte[] resonseByte = MakeTextPacket(message);
             foreach (TcpClient client in _clients)
             {
                 if (client != sender && IsClientConnected(client))

MySolution/SerialComApp/SerialCommApp.resx

@@ -121,7 +121,7 @@
   <data name="portRefreshButton.BackgroundImage" type="System.Drawing.Bitmap, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
     <value>
         iVBORw0KGgoAAAANSUhEUgAAADAAAAAwCAYAAABXAvmHAAAABGdBTUEAALGPC/xhBQAAAAlwSFlzAAAL
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+        DgAACw4BQL7hQQAAAsBJREFUaEPt2cnLTXEcx/FrzJCphJ0F2diIbEQokWFnzhClyFB6yEJEyh+gUMaU
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