Switches connections to attempt to connect to IP addresses in parallel

Needs to be tested on linux.

Author: ThadHouse

src/FRC.NetworkTables/Dispatcher.cs

@@ -4,6 +4,7 @@
 using NetworkTables.Interfaces;
 using NetworkTables.TcpSockets;
 using NetworkTables.Logging;
+using System;
 
 namespace NetworkTables
 {
@@ -45,22 +46,23 @@ public void StartServer(string persistentFilename, string listenAddress, int por
 
         public void SetServer(string serverName, int port)
         {
-            SetConnector(() => TcpConnector.Connect(serverName, port, Logger.Instance, 1));
+            SetConnector(() => TcpConnector.Connect(new List<(string server, int port)> { (serverName, port) }, Logger.Instance, TimeSpan.FromSeconds(1)));
         }
 
         public void SetServer(IList<NtIPAddress> servers)
         {
-            List<Connector> connectors = new List<Connector>();
+            List<(string server, int port)> addresses = new List<(string server, int port)>(servers.Count);
             foreach (var server in servers)
             {
-                connectors.Add(() => TcpConnector.Connect(server.IpAddress, server.Port, Logger.Instance, 1));
+                addresses.Add(server);
             }
-            SetConnector(connectors);
+
+            SetConnector(() => TcpConnector.Connect(addresses, Logger.Instance, TimeSpan.FromSeconds(1)));
         }
 
         public void SetServerOverride(IPAddress address, int port)
         {
-            SetConnectorOverride(() => TcpConnector.Connect(address.ToString(), port, Logger.Instance, 1));
+            SetConnectorOverride(() => TcpConnector.Connect(new List<(string server, int port)> { (address.ToString(), port) }, Logger.Instance, TimeSpan.FromSeconds(1)));
         }
 
         public void ClearServerOverride()

src/FRC.NetworkTables/DispatcherBase.cs

@@ -8,12 +8,13 @@
 using System.Threading.Tasks;
 using Nito.AsyncEx.Synchronous;
 using NetworkTables.Logging;
+using System.Net.Sockets;
 
 namespace NetworkTables
 {
     internal class DispatcherBase : IDisposable
     {
-        public delegate NtTcpClient Connector();
+        public delegate TcpClient Connector();
 
         public const double MinimumUpdateTime = 0.01; //100ms
         public const double MaximumUpdateTime = 1.0; //1 second
@@ -38,7 +39,7 @@ internal class DispatcherBase : IDisposable
         private bool m_doReconnect = true;
         private string m_identity = "";
 
-        private IList<Connector> m_clientConnectors = new List<Connector>(); 
+        private Connector m_clientConnector;
 
         private DateTime m_lastFlush;
 
@@ -153,15 +154,10 @@ public void StartClient()
         }
 
         public void SetConnector(Connector connector)
-        {
-            SetConnector(new List<Connector>() { connector });
-        }
-
-        public void SetConnector(IList<Connector> connectors)
         {
             lock (m_userMutex)
             {
-                m_clientConnectors = connectors;
+                m_clientConnector = connector;
             }
         }
 
@@ -191,7 +187,7 @@ public void Stop()
             //Wake up client thread with a reconnect
             lock (m_userMutex)
             {
-                m_clientConnectors.Clear();
+                m_clientConnector = null;
             }
             ClientReconnect();
 
@@ -360,7 +356,7 @@ private void ServerThreadMain()
                 }
                 if (!m_active) return;
 
-                if (stream.RemoteEndPoint is IPEndPoint ipEp)
+                if (stream.Client.RemoteEndPoint is IPEndPoint ipEp)
                 {
                     Debug(Logger.Instance, $"server: client connection from {ipEp.Address} port {ipEp.Port.ToString()}");
                 }
@@ -397,7 +393,6 @@ private void ServerThreadMain()
 
         private void ClientThreadMain()
         {
-            int i = 0;
             while (m_active)
             {
                 //Sleep between retries
@@ -407,16 +402,7 @@ private void ClientThreadMain()
 
                 lock (m_userMutex)
                 {
-                    if (m_clientConnectorOverride != null)
-                    {
-                        connect = m_clientConnectorOverride;
-                    }
-                    else
-                    {
-                        if (m_clientConnectors.Count == 0) continue;
-                        if (i >= m_clientConnectors.Count) i = 0;
-                        connect = m_clientConnectors[i++];
-                    }
+                    connect = m_clientConnectorOverride ?? m_clientConnector;
                 }
 
                 Debug(Logger.Instance, "client trying to connect");

src/FRC.NetworkTables/NetworkConnection.cs

@@ -5,14 +5,14 @@
 using System.Threading;
 using NetworkTables.Streams;
 using NetworkTables.Support;
-using NetworkTables.TcpSockets;
 using NetworkTables.Wire;
 using static NetworkTables.Logging.Logger;
 using System.IO;
 using System.Net;
 using System.Threading.Tasks;
 using Nito.AsyncEx.Synchronous;
 using NetworkTables.Logging;
+using System.Net.Sockets;
 
 namespace NetworkTables
 {
@@ -32,7 +32,7 @@ public enum State { Created, Init, Handshake, Synchronized, Active, Dead };
         private readonly Stream m_stream;
 
         // ReSharper disable once PrivateFieldCanBeConvertedToLocalVariable
-        private readonly IClient m_client;
+        private readonly TcpClient m_client;
 
         public int PeerPort { get; }
         public string PeerIP { get; }
@@ -64,7 +64,7 @@ public enum State { Created, Init, Handshake, Synchronized, Active, Dead };
 
         private readonly List<(int First, int Second)> m_pendingUpdate = new List<(int First, int Second)>();
 
-        public NetworkConnection(IClient client, Notifier notifier, HandshakeFunc handshake,
+        public NetworkConnection(TcpClient client, Notifier notifier, HandshakeFunc handshake,
             Message.GetEntryTypeFunc getEntryType)
         {
             Uid = (uint)Interlocked.Increment(ref s_uid) - 1;
@@ -79,7 +79,7 @@ public NetworkConnection(IClient client, Notifier notifier, HandshakeFunc handsh
             m_state = State.Created;
             LastUpdate = 0;
 
-            if (m_client.RemoteEndPoint is IPEndPoint ipEp)
+            if (m_client.Client.RemoteEndPoint is IPEndPoint ipEp)
             {
                 PeerIP = ipEp.Address.ToString();
                 PeerPort = ipEp.Port;

src/FRC.NetworkTables/TcpSockets/IClient.cs

@@ -1,11 +1,12 @@
 using System;
+using System.Net.Sockets;
 
 namespace NetworkTables.TcpSockets
 {
     internal interface INetworkAcceptor: IDisposable
     {
         int Start();
         void Shutdown();
-        IClient Accept();
+        TcpClient Accept();
     }
 }