Better block height determination

slothbag · Aug 19, 2015 · 86afac2 · 86afac2
1 parent 5d7a30e
commit 86afac2
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Showing 4 changed files with 62 additions and 30 deletions.
diff --git a/NxtLite/Nodes.cs b/NxtLite/Nodes.cs
@@ -32,15 +32,67 @@ public class Node {
 				this.address = address;
 			}
 		}
+
+		public class PeerBlockHeightHistory {
+			private int last_agreed_block_height = 0;
+
+			private struct PeerBlockHeight {
+				public string ip_address;
+				public int block_height;
+			}
+
+			private PeerBlockHeight[] History = new PeerBlockHeight[3];
+
+			public int AgreedBlockHeight {
+				get { return this.last_agreed_block_height; }
+			}
+
+			private bool TryUpdateToLatestBlockHeight() {
+				int min = 0;
+				int max = 0;
+				for (int a = 0; a < History.Length; a++) {
+					//if the history buffer is not full then no agreement yet
+					if (History[a].block_height == 0)
+						return false;
+
+					if (min == 0 || History[a].block_height < min)
+						min = History[a].block_height;
+					if (max == 0 || History[a].block_height > max)
+						max = History[a].block_height;
+				}
+				if (max - min < 3 && max > this.last_agreed_block_height) {
+					this.last_agreed_block_height = max;
+					return true;
+				}
+				else
+					return false;
+			}
+
+			public void Add(string ip_address, int block_height) {
+				bool bFound = false;
+				for (int a = 0; a < History.Length; a++) {
+					if (History[a].ip_address == ip_address) {
+						History[a].block_height = block_height;
+						bFound = true;
+					}
+				}
+				if (!bFound) {
+					//not found, add it
+					History[0] = History[1];
+					History[1] = History[2];
+					History[2] = new PeerBlockHeight() {ip_address = ip_address, block_height = block_height};
+				}
+
+				if (this.TryUpdateToLatestBlockHeight())
+					Console.WriteLine("Last block set to " + this.AgreedBlockHeight);
+			}
+		}
 
 		public static List<Nodes.Node> _nodes = new List<Nodes.Node>();
-		public static int[] block_height_history = new int[3];
-
-		public static int latest_block_height = 0;
+		public static PeerBlockHeightHistory peer_block_height_history = new PeerBlockHeightHistory();
 
 		public static bool AddNodes(string address) {
 			_nodes.Add(new Node(address));
-
 			return true;
 		}
 
@@ -154,28 +206,8 @@ orderby p.last_checked
 			return lNodes.First();
 		}
 
-		public static int ScanLatestBlockHeight() {
-			foreach (Node tmpNode in _nodes) {
-				if (tmpNode.block_height > latest_block_height) {
-					latest_block_height = tmpNode.block_height;
-					break;
-				}
-			}
-			return latest_block_height;
-		}
-
-		public static void SetLatestBlockHeight(int block_height) {
-			if (block_height_history.Max() - block_height_history.Min() < 3) {
-				if (block_height_history.Max() > latest_block_height) {
-					latest_block_height = block_height_history.Max();
-				}
-			}
-
-			//cycle the block history queue
-			block_height_history[0] = block_height_history[1];
-			block_height_history[1] = block_height_history[2];
-			block_height_history[2] = block_height;
-
+		public static void SetLatestBlockHeight(string ip_address, int block_height) {
+			peer_block_height_history.Add(ip_address, block_height);
 			return;
 		}
 

diff --git a/NxtLite/Program.cs b/NxtLite/Program.cs
@@ -20,7 +20,7 @@ private static void Main(string[] args)
 			else {
 				//try load existing settings
 				Nodes.LoadFromFile();
-				Nodes.ScanLatestBlockHeight();
+				//Nodes.ScanLatestBlockHeight();
 			}
 
 			//start the Core

diff --git a/NxtLite/WebServer.cs b/NxtLite/WebServer.cs
@@ -215,7 +215,7 @@ public void Run()
        			}
 
         		if (hasBlockHeight) {
-					if (publicNode.block_height < (Nodes.latest_block_height - 2)) {
+					if (publicNode.block_height < (Nodes.peer_block_height_history.AgreedBlockHeight - 2)) {
 	        		    publicNode.block_sync_failures ++;
 	        		    publicNode.consecutive_errors ++;
 	        		    publicNode.last_error = "Not fully sync'd";
@@ -225,7 +225,7 @@ public void Run()
 
         		publicNode.consecutive_errors = 0;
 				if (hasBlockHeight)
-        			Nodes.SetLatestBlockHeight(publicNode.block_height);
+					Nodes.peer_block_height_history.Add(publicNode.address, publicNode.block_height);
 
         		byte[] response_bytes = System.Text.Encoding.UTF8.GetBytes(response_data);
         		try {

diff --git a/gui_app/main.js b/gui_app/main.js
@@ -41,7 +41,7 @@ app.on('ready', function() {
   });
 
   // Create the browser window.
-  mainWindow = new BrowserWindow({width: 1360, height: 768, "node-integration": false, title: "NxtLite", icon: "icon32.png"});
+  mainWindow = new BrowserWindow({width: 1450, height: 768, "node-integration": false, title: "NxtLite", icon: "icon32.png"});
   mainWindow.setMenu(null);
 
   // and load the index.html of the app.