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Simple Notification Only C# WebSocket Server
if (WebSocketServer == null)
{
WebSocketServer = new MarkdownMonster.WebSockets.WebSocketServer();
WebSocketServer.StartServer();
WebSocketServer.OnBinaryMessage = (bytes) =>
{
App.CommandArgs = new[] {"untitled.base64," + Convert.ToBase64String(bytes)};
mmApp.Model.Window.Dispatcher.InvokeAsync(() => mmApp.Model.Window.OpenFilesFromCommandLine());
};
}
else
{
WebSocketServer?.StopServer();
WebSocketServer = null;
}
public class WebSocketServer
{
string IpAddress { get; set; } = "127.0.0.1";
int ServerPort { get; set; } = 5009;
Thread SocketThread { get; set; }
TcpListener TcpServer { get; set; }
public void StartServer(string ipAddress = "127.0.0.1", int serverPort = 5009)
{
SocketThread = new Thread(RunServer);
SocketThread.Start();
}
public void StopServer()
{
TcpServer?.Stop();
TcpServer = null;
SocketThread?.Abort();
SocketThread = null;
}
/// <summary>
/// Called when a Web Socket message has been captured.
/// This method returns the raw binary data.
///
/// Important: This occurs on a non-synchronized thread
/// so if you're using this in UI make sure to marshal
/// to the UI thread.
/// </summary>
public Action<byte[]> OnBinaryMessage;
/// <summary>
/// Called when a Web Socket message has been captured.
/// This method returns the data as a string.
///
/// Important: This occurs on a non-synchronized thread
/// so if you're using this in UI make sure to marshal
/// to the UI thread.
/// </summary>
public Action<string> OnStringMessage;
//public Action OnDisconnected;
//public Action<string> OnConnected;
public void RunServer()
{
TcpServer = new TcpListener(IPAddress.Parse(IpAddress),ServerPort);
TcpServer.Start();
TcpClient client = null;
NetworkStream stream = null;
// enter to an infinite cycle to be able to handle every change in stream
while (true)
{
if (client == null || !client.Connected)
client = TcpServer.AcceptTcpClient();
if (stream == null)
stream = client.GetStream();
var capturedData = new List<byte>();
while (!stream.DataAvailable)
{
Thread.Sleep(1); // don't hog CPU
while (client.Available < 3)
{
Thread.Sleep(10);
}
}
// Read initial buffer
byte[] bytes = new byte[client.Available];
stream.Read(bytes, 0, client.Available);
// check for handshake only if the block isn't very big
if (bytes.Length < 1028)
{
string s = Encoding.UTF8.GetString(bytes);
if (Regex.IsMatch(s, "^GET", RegexOptions.IgnoreCase))
{
// 1. Obtain the value of the "Sec-WebSocket-Key" request header without any leading or trailing whitespace
// 2. Concatenate it with "258EAFA5-E914-47DA-95CA-C5AB0DC85B11" (a special GUID specified by RFC 6455)
// 3. Compute SHA-1 and Base64 hash of the new value
// 4. Write the hash back as the value of "Sec-WebSocket-Accept" response header in an HTTP response
string swk = Regex.Match(s, "Sec-WebSocket-Key: (.*)").Groups[1].Value.Trim();
string swka = swk + "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
byte[] swkaSha1 = System.Security.Cryptography.SHA1.Create()
.ComputeHash(Encoding.UTF8.GetBytes(swka));
string swkaSha1Base64 = Convert.ToBase64String(swkaSha1);
// HTTP/1.1 defines the sequence CR LF as the end-of-line marker
byte[] response = Encoding.UTF8.GetBytes(
"HTTP/1.1 101 Switching Protocols\r\n" +
"Connection: Upgrade\r\n" +
"Upgrade: websocket\r\n" +
"Sec-WebSocket-Accept: " + swkaSha1Base64 + "\r\n\r\n");
stream.Write(response, 0, response.Length);
continue; // done here
}
}
// Capture Payload data
capturedData.AddRange(bytes);
// Read multiple buffers for large content
while (stream.DataAvailable)
{
try
{
stream.Read(bytes, 0, client.Available);
capturedData.AddRange(bytes);
}
catch
{
// TODO: needs specific exception handling for disconnects
}
}
bytes = capturedData.ToArray();
if (bytes.Length < 3)
continue; // nothing to do
List<byte> output = new List<byte>();
while (true)
{
bool fin = (bytes[0] & 0b10000000) != 0;
bool mask = (bytes[1] & 0b10000000) !=
0; // must be true, "All messages from the client to the server have this bit set"
int opcode = bytes[0] & 0b00001111; // expecting 1 - text message
int msglen = bytes[1] - 128, // & 0111 1111
offset = 2;
if (msglen == 126)
{
// was ToUInt16(bytes, offset) but the result is incorrect
msglen = BitConverter.ToUInt16(new byte[] {bytes[3], bytes[2]}, 0);
offset = 4;
}
else if (msglen == 127)
{
// TODO: This is broken in Chromium!!! returns 0 0 0 0 0 2 0 0 for any content with ml 127
msglen = (int) BitConverter.ToUInt64(
new byte[] {bytes[9], bytes[8], bytes[7], bytes[6], bytes[5], bytes[4], bytes[3], bytes[2]},
0);
offset = 10;
}
if (msglen == 0)
{
// nothing to do - empty message
}
else if (mask)
{
byte[] decoded = new byte[msglen];
byte[] masks = new byte[4]
{
bytes[offset], bytes[offset + 1], bytes[offset + 2], bytes[offset + 3]
};
offset += 4;
for (int i = 0; i < msglen; ++i)
decoded[i] = (byte) (bytes[offset + i] ^ masks[i % 4]);
output.AddRange(decoded);
if (!fin)
{
// keep going with the next frame
var off = msglen + offset;
var spanBytes = bytes.AsSpan<byte>(off);
bytes = spanBytes.ToArray(); //Array.Copy(bytes, off, b2, 0, bytes.Length - off);
}
else
break;
}
}
// Notifications if connected
OnBinaryMessage?.Invoke(output.ToArray());
OnStringMessage?.Invoke(Convert.ToBase64String(output.ToArray()));
}
}
}
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