Fix up the tracker sample a little

Addresses #605

However, it addresses the problem by listening on localhost. Ain't
nobody got time to figure out how to run as admin and unblock incoming
http requests on a regular old computer.

src/Samples/TrackerApp/Main.cs

@@ -88,8 +88,9 @@ public MySimpleTracker ()
             tracker = new TrackerServer ();
             tracker.AllowUnregisteredTorrents = true;
 
-            var httpEndpoint = new System.Net.IPEndPoint (System.Net.IPAddress.Any, 10000);
-            var udpEndpoint = new System.Net.IPEndPoint (System.Net.IPAddress.Any, 10001);
+            // Listen on a private address (localhost) in the sample.
+            var httpEndpoint = new System.Net.IPEndPoint (System.Net.IPAddress.Loopback, 10000);
+            var udpEndpoint = new System.Net.IPEndPoint (System.Net.IPAddress.Loopback, 10001);
             Console.WriteLine ("Listening for HTTP requests at: {0}", httpEndpoint);
             Console.WriteLine ("Listening for UDP requests at: {0}", udpEndpoint);
 
@@ -174,18 +175,22 @@ public static void Main (string[] args)
         private static void Benchmark ()
         {
             Console.Clear ();
-            Console.Write ("How many active torrents will be simulated: ");
-            int torrents = GetInt ();
-            Console.Write ("How many active peers per torrent: ");
-            int peers = GetInt ();
-            Console.Write ("How many requests per second: ");
-            int requests = GetInt ();
-
-            Console.Write ("What is the tracker address: ");
+            Console.Write ("How many active torrents will be simulated (default 10): ");
+            int torrents = GetInt (10);
+            Console.Write ("How many active peers per torrent (default 1000): ");
+            int peers = GetInt (1000);
+            Console.Write ("How many requests per second (default 100): ");
+            int requests = GetInt (100);
+
+            const string defaultAddress = "http://127.0.0.1:35277/announce/";
+            Console.WriteLine ("Read https://stackoverflow.com/questions/2583347/c-sharp-httplistener-without-using-netsh-to-register-a-uri to see how to listen on public IP addresses");
+            Console.Write ($"What is the tracker address (default {defaultAddress}): ");
             string address = Console.ReadLine ();
+            if (string.IsNullOrEmpty (address))
+                address = defaultAddress;
 
-            StressTest test = new StressTest (torrents, peers, requests);
-            test.Start (address);
+            StressTest test = new StressTest (torrents, peers, requests, address);
+            test.Start ();
 
             while (true) {
                 Console.WriteLine ("Measured announces/sec:  {0}", test.RequestRate);
@@ -200,10 +205,13 @@ private static void StartTracker ()
             new MySimpleTracker ();
         }
 
-        private static int GetInt ()
+        private static int GetInt (int? defaultValue = null)
         {
             while (true) {
-                if (int.TryParse (Console.ReadLine (), out int ret))
+                var data = Console.ReadLine ();
+                if (string.IsNullOrEmpty (data) && defaultValue.HasValue)
+                    return defaultValue.Value;
+                else if (int.TryParse (data, out int ret))
                     return ret;
             }
         }

src/Samples/TrackerApp/StressTest.cs

@@ -6,6 +6,9 @@
 using System.Threading.Tasks;
 
 using MonoTorrent;
+using MonoTorrent.Connections.TrackerServer;
+using MonoTorrent.Trackers;
+using MonoTorrent.TrackerServer;
 
 namespace TrackerApp
 {
@@ -17,6 +20,11 @@ public class StressTest
         readonly Thread[] threads;
         private readonly int threadSleepTime;
 
+        readonly HttpTrackerListener trackerListener;
+        readonly string trackerAddress;
+        readonly TrackerServer trackerServer;
+
+
         public int RequestRate {
             get { return (int) requests.Rate; }
         }
@@ -25,8 +33,10 @@ public long TotalTrackerRequests {
             get { return requests.Total; }
         }
 
-        public StressTest (int torrents, int peers, int requests)
+        public StressTest (int torrents, int peers, int requests, string trackerAddress)
         {
+            this.trackerAddress = trackerAddress;
+
             for (int i = 0; i < torrents; i++) {
                 byte[] infoHash = new byte[20];
                 random.NextBytes (infoHash);
@@ -35,9 +45,18 @@ public StressTest (int torrents, int peers, int requests)
 
             threadSleepTime = Math.Max ((int) (20000.0 / requests + 0.5), 1);
             threads = new Thread[20];
+
+            trackerListener = new HttpTrackerListener (trackerAddress);
+            trackerListener.Start ();
+
+            trackerServer = new TrackerServer {
+                AllowUnregisteredTorrents = true,
+                AllowScrape = true
+            };
+            trackerServer.RegisterListener (trackerListener);
         }
 
-        public void Start (string trackerAddress)
+        public void Start ()
         {
             var client = new HttpClient ();
             for (int i = 0; i < threads.Length; i++) {
@@ -47,11 +66,9 @@ public void Start (string trackerAddress)
                     while (true) {
                         sb.Remove (0, sb.Length);
 
-                        int ipaddress = random.Next (0, hashes.Count);
-
                         sb.Append (trackerAddress);
                         sb.Append ("?info_hash=");
-                        sb.Append (hashes[torrent++]);
+                        sb.Append (hashes[(torrent++) % hashes.Count]);
                         sb.Append ("&peer_id=");
                         sb.Append ("12345123451234512345");
                         sb.Append ("&port=");