ScreenExtender/PcWin/ScreenExtender/ScreenExtenderServer.cs

using ScreenExtender.Resources;
using System.IO;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace ScreenExtender
{
    internal class ScreenExtenderServer
    {
        private readonly ScreenExtenderMainForm _mainForm;

        private Socket _server;
        private bool _isRunning;

        public ScreenExtenderServer(ScreenExtenderMainForm mainForm)
        {
            _mainForm = mainForm;
        }

        public void Start(IPAddress listen, int port)
        {
            _server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
            _server.Bind(new IPEndPoint(listen, port));
            _server.Listen(1);

            _isRunning = true;
            Task.Factory.StartNew(ServerProc);
        }

        public void Stop()
        {
            _isRunning = false;
            _server?.Close();
            _server?.Dispose();
        }

        private void ServerProc()
        {
            while (_isRunning)
            {
                var client = _server.Accept();
                Task.Factory.StartNew(() => RequestProc(client));
            }
        }

        private void RequestProc(Socket client)
        {
            string req = "";
            {
                var buf = new byte[4096];
                var len = client.Receive(buf, 0, buf.Length, SocketFlags.None);
                //detect request

                var text = Encoding.ASCII.GetString(buf, 0, len);
                var lines = text.Split('\r', '\n');
                if (lines.Length > 0 && lines[0].StartsWith("GET"))
                {
                    var parts = lines[0].Split(new[] { ' ' }, 3);
                    if (parts.Length > 1) req = parts[1];
                }
            }

            var stream = new NetworkStream(client, true);

            if (req == "")
            {
                var ns = new NetworkStream(client);
                var w = new BinaryWriter(ns);
                while (_isRunning)
                {
                    Thread.Sleep(100);
                    var rBuf = _mainForm.FrameBytes;
                    if (rBuf == null) continue;

                    try
                    {
                        w.Write(rBuf.Length);
                        w.Write(rBuf);
                    }
                    catch (IOException)
                    {
                        break;
                    }
                }
                client.Close();
            }

            var path = req.Split('?')[0];

            switch (path)
            {
                case "/":
                    {
                        var rBuf = ResourceFetcher.IndexPage;
                        var writer = new BinaryWriter(stream);
                        writer.Write(Encoding.ASCII.GetBytes("HTTP/1.1 200 OK\r\n"));
                        writer.Write(Encoding.ASCII.GetBytes("Content-Type: text/html\r\n"));
                        writer.Write(Encoding.ASCII.GetBytes("Content-Length: " + rBuf.Length + "\r\n"));
                        writer.Write(Encoding.ASCII.GetBytes("\r\n"));
                        writer.Write(rBuf);
                        writer.Close();
                        client.Close();
                    }

                    break;

                case "/mjpeg":
                    {
                        var writer = new BinaryWriter(stream);
                        writer.Write(Encoding.ASCII.GetBytes("HTTP/1.1 200 OK\r\n"));
                        writer.Write(Encoding.ASCII.GetBytes("Content-Type: multipart/x-mixed-replace; boundary=frame\r\n"));

                        while (_isRunning)
                        {
                            var rBuf = _mainForm.FrameBytes;
                            if (rBuf == null)
                            {
                                Thread.Sleep(100);
                                continue;
                            }

                            writer.Write(Encoding.ASCII.GetBytes("\r\n"));
                            writer.Write(Encoding.ASCII.GetBytes("--frame\r\n"));

                            writer.Write(Encoding.ASCII.GetBytes("Content-Type: image/png\r\n"));
                            writer.Write(Encoding.ASCII.GetBytes("Content-Length: " + rBuf.Length + "\r\n"));
                            writer.Write(Encoding.ASCII.GetBytes("\r\n"));
                            writer.Write(rBuf);
                        }
                        client.Shutdown(SocketShutdown.Both);
                        client.Close();
                        client.Dispose();
                    }
                    break;

                case "/frame": //Single Picture Download,close
                    {
                        byte[] rBuf;
                        do
                        {
                            rBuf = _mainForm.FrameBytes;
                            if (rBuf != null) break;
                            Thread.Sleep(100);
                        } while (true);

                        var writer = new BinaryWriter(stream);
                        writer.Write(Encoding.ASCII.GetBytes("HTTP/1.1 200 OK\r\n"));
                        writer.Write(Encoding.ASCII.GetBytes("Content-Type: image/png\r\n"));
                        writer.Write(Encoding.ASCII.GetBytes("Content-Length: " + rBuf.Length + "\r\n"));
                        writer.Write(Encoding.ASCII.GetBytes("\r\n"));
                        writer.Write(rBuf);
                        writer.Close();
                        client.Close();
                    }
                    break;

                default:
                    client.Close();
                    break;
            }
        }
    }
}