dis be bork

YetAnotherDummy/Program.cs

@@ -1,6 +1,9 @@
 // See https://aka.ms/new-console-template for more information
 using System.Net;
 using System.Net.Sockets;
+using System.Numerics;
+using System.Text;
+using System.Text.RegularExpressions;
 using static RemoteFrameBufferClientProtocol;
 
 IPAddress tessia = new([192,168,16,253]);
@@ -76,7 +79,7 @@ public interface IRemoteFrameBufferClientStreamProvider
     }
 }
 
-public class RemoteFramebufferClient
+public partial class RemoteFramebufferClient
 {
     private static Dictionary<RfbProtoVersion, RemoteFrameBufferClientProtocol.IRemoteFramebufferClientProtocolFactory> _protocolHandlers;
 
@@ -117,13 +120,46 @@ public class RemoteFramebufferClient
 
     private void Worker()
     {
+        Int32 failcount = 0;
         while (!this.cancellationTokenSource.Token.IsCancellationRequested)
         {
             Console.Error.WriteLine("Attempting to connect");
             Stream s = this._socketProvider.GetRemoteFrameBufferClientStream();
             using (s)
             {
-
+                Byte[] buf = new Byte[12];
+                CancellationTokenSource readTimeout = new CancellationTokenSource(TimeSpan.FromSeconds(5));
+                CancellationTokenSource readTokenSource = CancellationTokenSource.CreateLinkedTokenSource(this.cancellationTokenSource.Token, readTimeout.Token);
+                try
+                {
+                    s.ReadExactlyAsync(buf, 0, buf.Length, readTokenSource.Token).AsTask().Wait();
+                }catch (AggregateException e)// TODO: go through InnerExceptions and only throw if we are left with unhandled ones
+                {
+                    if (e.InnerException is TaskCanceledException)
+                    {
+                        if (failcount++ >= 5)
+                        {
+                            break;
+                        }
+                        Task.Delay(1000).Wait();
+                        continue;
+                    }else
+                    {
+                        throw new Exception("Something broke. Yeah, I know, very useful message.", e);
+                    }
+                }
+                failcount = 0;
+                String protover = Encoding.ASCII.GetString(buf);
+                Console.Error.Write($"Server protocol: {protover}");
+                Match m = _rfbVersionRegex().Match(protover);
+                if (!m.Success)
+                {
+                    throw new Exception("Cannot parse protocol version");
+                }
+                RfbProtoVersion serverVersion = new(Int16.Parse(m.Groups["major"].Value), Int16.Parse(m.Groups["minor"].Value));
+                RfbProtoVersion maxProto = _protocolHandlers.Keys.Where((ph) => ph <= serverVersion).Max();
+                RemoteFrameBufferClientProtocol proto = _protocolHandlers[maxProto].Construct(s);
+                Console.Error.WriteLine($"Using client protocol {proto.Version.Major}.{proto.Version.Minor}");
             }
 
         }
@@ -139,17 +175,50 @@ public class RemoteFramebufferClient
         }
     }
 
-    private struct RfbProtoVersion(Int16 major, Int16 minor)
-    {
-        public Int16 Major = major;
-        public Int16 Minor = minor;
-    }
-
+    [GeneratedRegex(@"^RFB (?'major'\d{3}).(?'minor'\d{3})$")]
+    private static partial Regex _rfbVersionRegex();
 }
+public struct RfbProtoVersion(Int16 major, Int16 minor)
+{
+    public Int16 Major = major;
+    public Int16 Minor = minor;
 
+
+    public static Boolean operator ==(RfbProtoVersion a, RfbProtoVersion b)
+    {
+        return (a.Major == b.Major) && (a.Minor == b.Minor);
+    }
+    public static Boolean operator !=(RfbProtoVersion a, RfbProtoVersion b)
+    {
+        return !(a == b);
+    }
+    public static Boolean operator <(RfbProtoVersion a, RfbProtoVersion b)
+    {
+        if (a.Major == b.Major)
+        {
+            return a.Minor < b.Minor;
+        } else
+        {
+            return a.Major < b.Major;
+        }
+    }
+    public static Boolean operator >(RfbProtoVersion a, RfbProtoVersion b)
+    {
+        return b < a;
+    }
+    public static Boolean operator <=(RfbProtoVersion a, RfbProtoVersion b)
+    {
+        return b < a;
+    }
+    public static Boolean operator >=(RfbProtoVersion a, RfbProtoVersion b)
+    {
+        return a < b;
+    }
+}
 public abstract class RemoteFrameBufferClientProtocol
 {
     protected readonly Stream vncStream;
+    public abstract RfbProtoVersion Version { get; }
 
     public RemoteFrameBufferClientProtocol(Stream s)
     {
@@ -169,6 +238,8 @@ public abstract class RemoteFrameBufferClientProtocol
 
     public class RemoteFrameBufferClientProtocol_3_3 : RemoteFrameBufferClientProtocol
     {
+        public override RfbProtoVersion Version => new(3,3);
+
         public RemoteFrameBufferClientProtocol_3_3(Stream s) : base(s)
         {
         }