From b305594ea40d1eb8a2868d98b8a70b93f28dc082 Mon Sep 17 00:00:00 2001
From: Niklas Kapelle <niklas@kapelle.org>
Date: Tue, 15 Oct 2024 01:19:36 +0200
Subject: [PATCH] improved networking

---
 src/kernel/net/Net.hx     | 39 +++++++++++++++++++++--
 src/kernel/net/Routing.hx | 66 ++++++++++++++++++++++++++-------------
 2 files changed, 81 insertions(+), 24 deletions(-)

diff --git a/src/kernel/net/Net.hx b/src/kernel/net/Net.hx
index 18e7fed..ccd888c 100644
--- a/src/kernel/net/Net.hx
+++ b/src/kernel/net/Net.hx
@@ -39,6 +39,35 @@ class Net {
 			setupInterf(interf);
 		}
 
+		// Handle when a modem has been removed
+		KernelEvents.onPeripheralDetach.handle((addr) -> {
+			var idx = interfaces.findIndex((i) -> {
+				return i.name() == addr;
+			});
+			if (idx == -1) {
+				return;
+			}
+
+			Log.debug('Removed modem on addr: $addr');
+
+			interfaces.splice(idx, 1);
+			Routing.removeInterface(addr);
+		});
+
+		// Handle when a new modem is connected
+		KernelEvents.onPeripheral.handle((addr) -> {
+			if (!Peripheral.getTypes(addr).contains("modem")) {
+				return;
+			}
+
+			Log.debug('Added modem on addr: $addr');
+
+			var modem = Peripheral.getModem(addr);
+			interfaces.push(modem);
+			setupInterf(modem);
+			Routing.addInterface(modem);
+		});
+
 		setupPingHandle();
 
 		Routing.setup();
@@ -62,6 +91,9 @@ class Net {
 		});
 	}
 
+	/**
+		Enables the interface to receive messages.
+	**/
 	private static function setupInterf(interf:INetworkInterface) {
 		interf.onMessage.handle(e -> handle(e.pack, interf, e.dist));
 		interf.listen(networkID);
@@ -135,12 +167,13 @@ class Net {
 
 		if (!sendRaw(pack)) {
 			// Cant forward
+			Log.silly('Received a message that could not be forwarded to ${pack.toID}');
 		}
 	}
 
 	public static function respondTo(pack:GenericPackage, data:Dynamic) {
-		if (pack.type.match(DataNoResponse(_))) {
-			Log.warn("Responed to a no response package. Ignoring");
+		if (!pack.type.match(Data(_))) {
+			Log.warn("Responding to a package that does require responding. Ignoring.");
 			return;
 		}
 
@@ -212,6 +245,8 @@ class Net {
 				if (timeout != null) {
 					timeout.cancle();
 				}
+
+				responseBus.remove(pack.msgID);
 			});
 
 			timeout = new Timer(MESSAGE_TIMEOUT, () -> {
diff --git a/src/kernel/net/Routing.hx b/src/kernel/net/Routing.hx
index be0cfc3..4939543 100644
--- a/src/kernel/net/Routing.hx
+++ b/src/kernel/net/Routing.hx
@@ -74,42 +74,37 @@ class Routing {
 	private static function handleRoutePackage(pack:Package<Noise>, interf:INetworkInterface):Void {
 		addPossibleRoute(pack.fromID, interf, 0, pack.fromID);
 
-		var shouldRespond:Bool = switch pack.type {
+		switch pack.type {
 			case RouteDiscoverResponse(routes):
+				// A request for routes has been answerd
 				for (route in routes) {
 					addPossibleRoute(route.id, interf, route.cost, pack.fromID);
 				}
-				false;
 			case RouteDiscover(routes):
+				// Received a request for available routes
 				for (route in routes) {
 					addPossibleRoute(route.id, interf, route.cost, pack.fromID);
 				}
-				true;
+
+				// Respond to peer
+				var response:Package<Noise> = {
+					toID: pack.fromID,
+					fromID: Net.networkID,
+					msgID: null,
+					type: RouteDiscoverResponse(genRouteList()),
+					data: null,
+					ttl: 0, // Prevent forwarding
+				}
+
+				interf.send(response.toID, Net.networkID, response);
 			case RouteDiscoverUpdate(routes):
+				// Received an update of routes
 				for (route in routes) {
 					addPossibleRoute(route.id, interf, route.cost, pack.fromID);
 				}
-				false;
 			default:
-				Log.error("Expected package to be a Route discover package");
-				false;
+				Log.silly("Expected package to be a Route discover package");
 		};
-
-		if (!shouldRespond) {
-			return;
-		}
-
-		// Respond to peer
-		var response:Package<Noise> = {
-			toID: pack.fromID,
-			fromID: Net.networkID,
-			msgID: null,
-			type: RouteDiscoverResponse(genRouteList()),
-			data: null,
-			ttl: 0, // Prevent forwarding
-		}
-
-		interf.send(response.toID, Net.networkID, response);
 	}
 
 	/**
@@ -126,6 +121,9 @@ class Routing {
 		return routes;
 	}
 
+	/**
+		Create a new packate to brodcast our routes.
+	**/
 	private static function newRoutDiscoverPackage():Package<Noise> {
 		var pack:Package<Noise> = {
 			type: RouteDiscover(genRouteList()),
@@ -179,4 +177,28 @@ class Routing {
 	public static function getRouteTable():Map<NetworkID, Route> {
 		return routingTable;
 	}
+
+	/**
+		Call when an interface is no longer available.
+		Will rebrodcast routing requests.
+	**/
+	@:allow(kernel.net.Net)
+	private static function removeInterface(addr:String) {
+		// Remove the interface from the routing table
+		for (to => modem in routingTable) {
+			if (modem.interf.name() == addr) {
+				routingTable.remove(to);
+			}
+		}
+
+		// Since some routes to some host could be lost
+		// we rebrodcast on all interfaces again
+		brodcastRoutingTable();
+	}
+
+	@:allow(kernel.net.Net)
+	private static function addInterface(iface:INetworkInterface) {
+		var pack = newRoutDiscoverPackage();
+		iface.send(Net.BRODCAST_PORT, Net.networkID, pack);
+	}
 }