Ensure that hook method #3 receieves Packet0KeepAlive.

ProtocolLib/src/com/comphenix/protocol/ProtocolLibrary.java

@@ -53,8 +53,7 @@ public class ProtocolLibrary extends JavaPlugin {
 	@Override
 	public void onLoad() {
 		logger = getLoggerSafely();
-		protocolManager = new PacketFilterManager(
-				getClassLoader(), getServer().getScheduler(), logger);
+		protocolManager = new PacketFilterManager(getClassLoader(), getServer(), logger);
 	}
 	
 	@Override

ProtocolLib/src/com/comphenix/protocol/injector/InjectedServerConnection.java

@@ -0,0 +1,189 @@
+package com.comphenix.protocol.injector;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import org.bukkit.Server;
+
+import com.comphenix.protocol.reflect.FieldUtils;
+import com.comphenix.protocol.reflect.FuzzyReflection;
+import com.comphenix.protocol.reflect.VolatileField;
+
+/**
+ * Used to ensure that the 1.3 server is referencing the correct server handler.
+ * 
+ * @author Kristian
+ */
+class InjectedServerConnection {
+	
+	private static Field listenerThreadField;
+	private static Field minecraftServerField;
+	private static Method serverConnectionMethod;
+	private static Field listField;
+	
+	private List<VolatileField> listFields;
+	private List<ReplacedArrayList<Object>> replacedLists;
+	
+	private Server server;
+	private Logger logger;
+	private boolean hasAttempted;
+	private boolean hasSuccess;
+	
+	private Object minecraftServer = null;
+	
+	public InjectedServerConnection(Logger logger, Server server) {
+		this.listFields = new ArrayList<VolatileField>();
+		this.replacedLists = new ArrayList<ReplacedArrayList<Object>>();
+		this.logger = logger;
+		this.server = server;
+	}
+
+	public void injectList() {
+
+		// Only execute this method once
+		if (!hasAttempted)
+			hasAttempted = true;
+		else
+			return;
+		
+		if (minecraftServerField == null)
+			minecraftServerField = FuzzyReflection.fromObject(server, true).getFieldByType(".*MinecraftServer");
+
+		try {
+			minecraftServer = FieldUtils.readField(minecraftServerField, server, true);
+		} catch (IllegalAccessException e1) {
+			logger.log(Level.WARNING, "Cannot extract minecraft server from Bukkit.");
+			return;
+		}
+		
+		try {
+			if (serverConnectionMethod == null)
+				serverConnectionMethod = FuzzyReflection.fromClass(minecraftServerField.getType()).
+											getMethodByParameters("getServerConnection", ".*ServerConnection", new String[] {});
+			// We're using Minecraft 1.3.1
+			injectServerConnection();
+		
+		} catch (RuntimeException e) {
+			
+			// Minecraft 1.2.5 or lower
+			injectListenerThread();
+		}
+	}
+	
+	private void injectListenerThread() {
+	
+		try {
+		
+		if (listenerThreadField == null)
+			listenerThreadField = FuzzyReflection.fromClass(minecraftServerField.getType()).
+				getFieldByType(".*NetworkListenThread");
+		} catch (RuntimeException e) {
+			logger.log(Level.SEVERE, "Cannot find listener thread in MinecraftServer.");
+			return;
+		}
+
+		Object listenerThread = null;
+		
+		// Attempt to get the thread
+		try {
+			listenerThread = listenerThreadField.get(minecraftServer);
+		} catch (Exception e) {
+			logger.log(Level.WARNING, "Unable to read the listener thread.");
+			return;
+		}
+		
+		// Ok, great. Get every list field
+		List<Field> lists = FuzzyReflection.fromClass(listenerThreadField.getType()).getFieldListByType(List.class);
+		
+		for (Field list : lists) {
+			injectIntoList(listenerThread, list);
+		}
+		
+		hasSuccess = true;
+	}
+	
+	private void injectServerConnection() {
+		
+		Object serverConnection = null;
+		
+		// Careful - we might fail
+		try {
+			serverConnection = serverConnectionMethod.invoke(minecraftServer);
+		} catch (Exception ex) {
+			logger.log(Level.WARNING, "Unable to retrieve server connection", ex);
+			return;
+		}
+		
+		if (listField == null)
+			listField = FuzzyReflection.fromClass(serverConnectionMethod.getReturnType(), true).
+							getFieldByType("serverConnection", List.class);
+		injectIntoList(serverConnection, listField);
+		hasSuccess = true;
+	}
+	
+	@SuppressWarnings("unchecked")
+	private void injectIntoList(Object instance, Field field) {
+		VolatileField listFieldRef = new VolatileField(listField, instance, true);
+		List<Object> list = (List<Object>) listFieldRef.getValue();
+
+		// Careful not to inject twice
+		if (list instanceof ReplacedArrayList) {
+			replacedLists.add((ReplacedArrayList<Object>) list);
+		} else {
+			replacedLists.add(new ReplacedArrayList<Object>(list));
+			listFieldRef.setValue(replacedLists.get(0));
+			listFields.add(listFieldRef);
+		}
+	}
+	
+	/**
+	 * Replace the server handler instance kept by the "keep alive" object.
+	 * @param oldHandler - old server handler.
+	 * @param newHandler - new, proxied server handler.
+	 */
+	public void replaceServerHandler(Object oldHandler, Object newHandler) {
+		if (!hasAttempted) {
+			injectList();
+		}
+		
+		if (hasSuccess) {
+			for (ReplacedArrayList<Object> replacedList : replacedLists) {
+				replacedList.addMapping(oldHandler, newHandler);
+			}
+		}
+	}
+	
+	/**
+	 * Revert to the old vanilla server handler, if it has been replaced.
+	 * @param oldHandler - old vanilla server handler.
+	 */
+	public void revertServerHandler(Object oldHandler) {
+		if (hasSuccess) {
+			for (ReplacedArrayList<Object> replacedList : replacedLists) {
+				replacedList.removeMapping(oldHandler);
+			}
+		}
+	}
+	
+	/**
+	 * Undoes everything.
+	 */
+	public void cleanupAll() {
+		if (replacedLists.size() > 0) {
+			// Repair the underlying lists
+			for (ReplacedArrayList<Object> replacedList : replacedLists) {
+				replacedList.revertAll();
+			}
+			for (VolatileField field : listFields) {
+				field.revertValue();
+			}
+			
+			listFields.clear();
+			replacedLists.clear();
+		}
+	}
+}

ProtocolLib/src/com/comphenix/protocol/injector/MinecraftRegistry.java

@@ -49,7 +49,7 @@ class MinecraftRegistry {
 		// Initialize it, if we haven't already
 		if (packetToID == null) {
 			try {
-				Field packetsField = FuzzyReflection.fromClass(Packet.class, true).getFieldByType("java\\.util\\.Map");
+				Field packetsField = FuzzyReflection.fromClass(Packet.class, true).getFieldByType("packetsField", Map.class);
 				packetToID = (Map<Class, Integer>) FieldUtils.readStaticField(packetsField, true);
 				
 			} catch (IllegalAccessException e) {

ProtocolLib/src/com/comphenix/protocol/injector/NetworkServerInjector.java

@@ -13,8 +13,10 @@ import net.sf.cglib.proxy.MethodProxy;
 import org.bukkit.entity.Player;
 
 import com.comphenix.protocol.events.PacketListener;
+import com.comphenix.protocol.reflect.FieldAccessException;
 import com.comphenix.protocol.reflect.FieldUtils;
 import com.comphenix.protocol.reflect.FuzzyReflection;
+import com.comphenix.protocol.reflect.StructureModifier;
 import com.comphenix.protocol.reflect.instances.CollectionGenerator;
 import com.comphenix.protocol.reflect.instances.DefaultInstances;
 import com.comphenix.protocol.reflect.instances.ExistingGenerator;
@@ -28,9 +30,14 @@ import com.comphenix.protocol.reflect.instances.PrimitiveGenerator;
 public class NetworkServerInjector extends PlayerInjector {
 
 	private static Method sendPacketMethod;
+
+	private StructureModifier<Object> serverHandlerModifier;
+	private InjectedServerConnection serverInjection;
 	
-	public NetworkServerInjector(Player player, PacketFilterManager manager, Set<Integer> sendingFilters) throws IllegalAccessException {
+	public NetworkServerInjector(Player player, PacketFilterManager manager, 
+								 Set<Integer> sendingFilters, InjectedServerConnection serverInjection) throws IllegalAccessException {
 		super(player, manager, sendingFilters);
+		this.serverInjection = serverInjection;
 	}
 	
 	@Override
@@ -41,6 +48,8 @@ public class NetworkServerInjector extends PlayerInjector {
 		if (hasInitialized) {
 			if (sendPacketMethod == null)
 				sendPacketMethod = FuzzyReflection.fromObject(serverHandler).getMethodByName("sendPacket.*");
+			if (serverHandlerModifier == null)
+				serverHandlerModifier = new StructureModifier<Object>(serverHandler.getClass(), null, false);
 		}
 	}
 
@@ -98,12 +107,8 @@ public class NetworkServerInjector extends PlayerInjector {
 					}
 				}
 				
-				// Delegate to our underlying class
-				try {
-					return method.invoke(serverHandler, args);
-				} catch (InvocationTargetException e) {
-					throw e.getCause();
-				}
+				// Call the method directly
+				return proxy.invokeSuper(obj, args);
 			}
 		});
 		
@@ -114,22 +119,46 @@ public class NetworkServerInjector extends PlayerInjector {
 				CollectionGenerator.INSTANCE);
 
 		Object proxyObject = serverInstances.forEnhancer(ex).getDefault(serverClass);
-
+		serverInjection.replaceServerHandler(serverHandler, proxyObject);
+		
 		// Inject it now
 		if (proxyObject != null) {
+			copyTo(serverHandler, proxyObject);
 			serverHandlerRef.setValue(proxyObject);
 		} else {
 			throw new RuntimeException(
 					"Cannot hook player: Unable to find a valid constructor for the NetServerHandler object.");
 		}
 	}
-
+	
+	/**
+	 * Copy every field in server handler A to server handler B.
+	 * @param source - fields to copy.
+	 * @param destination - fields to copy to.
+	 */
+	private void copyTo(Object source, Object destination) {
+		StructureModifier<Object> modifierSource = serverHandlerModifier.withTarget(source);
+		StructureModifier<Object> modifierDest = serverHandlerModifier.withTarget(destination);
+		
+		// Copy every field
+		try {
+			for (int i = 0; i < modifierSource.size(); i++) {
+					modifierDest.write(i, modifierSource.read(i));
+			}
+		} catch (FieldAccessException e) {
+			throw new RuntimeException("Unable to copy fields from NetServerHandler.", e);
+		}
+	}
+	
 	@Override
 	public void cleanupAll() {
-		if (serverHandlerRef != null) {
+		if (serverHandlerRef != null && serverHandlerRef.isCurrentSet()) {
+			copyTo(serverHandlerRef.getValue(), serverHandlerRef.getOldValue());
 			serverHandlerRef.revertValue();
 		}
 		
+		serverInjection.revertServerHandler(serverHandler);
+		
 		try {
 			if (getNetHandler() != null) {
 				// Restore packet listener

ProtocolLib/src/com/comphenix/protocol/injector/PacketFilterManager.java

@@ -34,6 +34,7 @@ import net.sf.cglib.proxy.Enhancer;
 import net.sf.cglib.proxy.MethodInterceptor;
 import net.sf.cglib.proxy.MethodProxy;
 
+import org.bukkit.Server;
 import org.bukkit.entity.Entity;
 import org.bukkit.entity.Player;
 import org.bukkit.event.EventHandler;
@@ -44,7 +45,6 @@ import org.bukkit.event.player.PlayerQuitEvent;
 import org.bukkit.event.server.PluginDisableEvent;
 import org.bukkit.plugin.Plugin;
 import org.bukkit.plugin.PluginManager;
-import org.bukkit.scheduler.BukkitScheduler;
 
 import com.comphenix.protocol.AsynchronousManager;
 import com.comphenix.protocol.ProtocolManager;
@@ -92,11 +92,14 @@ public final class PacketFilterManager implements ProtocolManager {
 	private Map<Player, PlayerInjector> playerInjection = new HashMap<Player, PlayerInjector>();
 	
 	// Player injection type
-	private PlayerInjectHooks playerHook = PlayerInjectHooks.NETWORK_SERVER_OBJECT;
+	private PlayerInjectHooks playerHook = PlayerInjectHooks.NETWORK_HANDLER_FIELDS;
 	
 	// Packet injection
 	private PacketInjector packetInjector;
 	
+	// Server connection injection
+	private InjectedServerConnection serverInjection;
+	
 	// Enabled packet filters
 	private Set<Integer> sendingFilters = Collections.newSetFromMap(new ConcurrentHashMap<Integer, Boolean>());
 	
@@ -122,7 +125,7 @@ public final class PacketFilterManager implements ProtocolManager {
 	/**
 	 * Only create instances of this class if protocol lib is disabled.
 	 */
-	public PacketFilterManager(ClassLoader classLoader, BukkitScheduler scheduler, Logger logger) {
+	public PacketFilterManager(ClassLoader classLoader, Server server, Logger logger) {
 		if (logger == null)
 			throw new IllegalArgumentException("logger cannot be NULL.");
 		if (classLoader == null)
@@ -133,7 +136,8 @@ public final class PacketFilterManager implements ProtocolManager {
 			this.classLoader = classLoader;
 			this.logger = logger;
 			this.packetInjector = new PacketInjector(classLoader, this, connectionLookup);
-			this.asyncFilterManager = new AsyncFilterManager(logger, scheduler, this);
+			this.asyncFilterManager = new AsyncFilterManager(logger, server.getScheduler(), this);
+			this.serverInjection = new InjectedServerConnection(logger, server);
 		} catch (IllegalAccessException e) {
 			logger.log(Level.SEVERE, "Unable to initialize packet injector.", e);
 		}
@@ -474,7 +478,7 @@ public final class PacketFilterManager implements ProtocolManager {
 		case NETWORK_MANAGER_OBJECT: 
 			return new NetworkObjectInjector(player, this, sendingFilters);
 		case NETWORK_SERVER_OBJECT:
-			return new NetworkServerInjector(player, this, sendingFilters);
+			return new NetworkServerInjector(player, this, sendingFilters, serverInjection);
 		default:
 			throw new IllegalArgumentException("Cannot construct a player injector.");
 		}
@@ -714,6 +718,8 @@ public final class PacketFilterManager implements ProtocolManager {
 		if (packetInjector != null)
 			packetInjector.cleanupAll();
 		
+		// Remove server handler
+		serverInjection.cleanupAll();
 		hasClosed = true;
 		
 		// Remove listeners

ProtocolLib/src/com/comphenix/protocol/injector/PlayerInjector.java

@@ -221,6 +221,7 @@ abstract class PlayerInjector {
 	Packet handlePacketRecieved(Packet packet) {
 		// Get the packet ID too
 		Integer id = MinecraftRegistry.getPacketToID().get(packet.getClass());
+		System.out.println(id);
 
 		// Make sure we're listening
 		if (id != null && sendingFilters.contains(id)) {	

ProtocolLib/src/com/comphenix/protocol/injector/ReplacedArrayList.java

@@ -0,0 +1,136 @@
+package com.comphenix.protocol.injector;
+
+import java.util.Collection;
+import java.util.List;
+
+import com.google.common.base.Objects;
+import com.google.common.collect.BiMap;
+import com.google.common.collect.ForwardingList;
+import com.google.common.collect.HashBiMap;
+
+/**
+ * Represents an array list that wraps another list, while automatically replacing one element with another.
+ * <p>
+ * The replaced elements can be recovered. 
+ * 
+ * @author Kristian
+ * @param <TKey> - type of the elements we're replacing.
+ */
+class ReplacedArrayList<TKey> extends ForwardingList<TKey> {
+	private BiMap<TKey, TKey> replaceMap = HashBiMap.create();
+	private List<TKey> underlyingList;
+	
+	public ReplacedArrayList(List<TKey> underlyingList) {
+		this.underlyingList = underlyingList;
+	}
+	
+	@Override
+	public boolean add(TKey element) {
+		if (replaceMap.containsKey(element)) {
+			return super.add(replaceMap.get(element));
+		} else {
+			return super.add(element);
+		}
+	}
+	
+	@Override
+	public void add(int index, TKey element) {
+		if (replaceMap.containsKey(element)) {
+			super.add(index, replaceMap.get(element));
+		} else {
+			super.add(index, element);
+		}
+	}
+	
+	@Override
+	public boolean addAll(Collection<? extends TKey> collection) {
+		int oldSize = size();
+		
+		for (TKey element : collection)
+			add(element);
+		return size() != oldSize;
+	}
+	
+	@Override
+	public boolean addAll(int index, Collection<? extends TKey> elements) {
+		int oldSize = size();
+		
+		for (TKey element : elements)
+			add(index++, element);
+		return size() != oldSize;
+	}
+	
+	@Override
+	protected List<TKey> delegate() {
+		return underlyingList;
+	}
+
+	/**
+	 * Add a replace rule.
+	 * <p>
+	 * This automatically replaces every existing element.
+	 * @param target - instance to find.
+	 * @param replacement - instance to replace with.
+	 */
+	public synchronized void addMapping(TKey target, TKey replacement) {
+		replaceMap.put(target, replacement);
+
+		// Replace existing elements
+		replaceAll(target, replacement);
+	}
+	
+	/**
+	 * Revert the given mapping.
+	 * @param target - the instance we replaced.
+	 */
+	public synchronized void removeMapping(TKey target) {
+		// Make sure the mapping exist
+		if (replaceMap.containsKey(target)) {
+			TKey replacement = replaceMap.get(target);
+			replaceMap.remove(target);
+	
+			// Revert existing elements
+			replaceAll(replacement, target);
+		}
+	}
+	
+	/**
+	 * Replace all instances of the given object.
+	 * @param find - object to find.
+	 * @param replace - object to replace it with.
+	 */
+	public synchronized void replaceAll(TKey find, TKey replace) {
+		for (int i = 0; i < underlyingList.size(); i++) {
+			if (Objects.equal(underlyingList.get(i), find))
+				underlyingList.set(i, replace);
+		}
+	}
+	
+	/**
+	 * Undo all replacements.
+	 */
+	public synchronized void revertAll() {
+		
+		// No need to do anything else
+		if (replaceMap.size() < 1)
+			return;
+		
+		BiMap<TKey, TKey> inverse = replaceMap.inverse();
+		
+		for (int i = 0; i < underlyingList.size(); i++) {
+			TKey replaced = underlyingList.get(i);
+			
+			if (inverse.containsKey(replaced)) {
+				underlyingList.set(i, inverse.get(replaced));
+			}
+		}
+		
+		replaceMap.clear();
+	}
+	
+	@Override
+	protected void finalize() throws Throwable {
+		revertAll();
+		super.finalize();
+	}
+}

ProtocolLib/src/com/comphenix/protocol/reflect/FuzzyReflection.java

@@ -142,11 +142,38 @@ public class FuzzyReflection {
 	 * @return The first method that satisfies the parameter types.
 	 */
 	public Method getMethodByParameters(String name, Class<?> returnType, Class<?>[] args) {
+		// Find the correct method to call
+		List<Method> methods = getMethodListByParameters(returnType, args);
+		
+		if (methods.size() > 0) {
+			return methods.get(0);
+		} else {
+			// That sucks
+			throw new RuntimeException("Unable to find " + name + " in " + source.getName());
+		}
+	}
 	
+	/**
+	 * Retrieves a method by looking at the parameter types and return type only.
+	 * @param name - potential name of the method. Only used by the error mechanism.
+	 * @param returnType - regular expression matching the return type of the method to find.
+	 * @param args - regular expressions of the matching parameter types.
+	 * @return The first method that satisfies the parameter types.
+	 */
+	public Method getMethodByParameters(String name, String returnTypeRegex, String[] argsRegex) {
+	
+		Pattern match = Pattern.compile(returnTypeRegex);
+		Pattern[] argMatch = new Pattern[argsRegex.length];
+		
+		for (int i = 0; i < argsRegex.length; i++) {
+			argMatch[i] = Pattern.compile(argsRegex[i]);
+		}
+		
 		// Find the correct method to call
 		for (Method method : getMethods()) {
-			if (method.getReturnType().equals(returnType) && Arrays.equals(method.getParameterTypes(), args)) {
-				return method;
+			if (match.matcher(method.getReturnType().getName()).matches()) {
+				if (matchParameters(argMatch, method.getParameterTypes()))
+					return method;
 			}
 		}
 		
@@ -154,6 +181,19 @@ public class FuzzyReflection {
 		throw new RuntimeException("Unable to find " + name + " in " + source.getName());
 	}
 	
+	private boolean matchParameters(Pattern[] parameterMatchers, Class<?>[] argTypes) {
+		if (parameterMatchers.length != argTypes.length)
+			throw new IllegalArgumentException("Arrays must have the same cardinality.");
+		
+		// Check types against the regular expressions
+		for (int i = 0; i < argTypes.length; i++) {
+			if (!parameterMatchers[i].matcher(argTypes[i].getName()).matches())
+				return false;
+		}
+		
+		return true;
+	}
+	
 	/**
 	 * Retrieves every method that has the given parameter types and return type.
 	 * @param returnType - return type of the method to find.
@@ -195,6 +235,46 @@ public class FuzzyReflection {
 									nameRegex + " in " + source.getName());
 	}
 	
+	/**
+	 * Retrieves the first field with a type equal to or more specific to the given type.
+	 * @param name - name the field probably is given. This will only be used in the error message.
+	 * @param type - type of the field to find.
+	 * @return The first field with a type that is an instance of the given type.
+	 */
+	public Field getFieldByType(String name, Class<?> type) {
+		
+		List<Field> fields = getFieldListByType(type);
+		
+		if (fields.size() > 0) {
+			return fields.get(0);
+		} else {
+			// Looks like we're outdated. Too bad.
+			throw new RuntimeException(String.format("Unable to find a field %s with the type %s in %s",
+					name, type.getName(), source.getName())
+			);
+		}
+	}
+	
+	/**
+	 * Retrieves every field with a type equal to or more specific to the given type.
+	 * @param type - type of the fields to find.
+	 * @return Every field with a type that is an instance of the given type.
+	 */
+	public List<Field> getFieldListByType(Class<?> type) {
+		
+		List<Field> fields = new ArrayList<Field>();
+		
+		// Field with a compatible type
+		for (Field field : getFields()) {
+			// A assignable from B -> B instanceOf A
+			if (type.isAssignableFrom(field.getType())) {
+				fields.add(field);
+			}
+		}
+		
+		return fields;
+	}
+	
 	/**
 	 * Retrieves a field by type.
 	 * <p>

ProtocolLib/src/com/comphenix/protocol/reflect/VolatileField.java

@@ -155,6 +155,13 @@ public class VolatileField {
 		}
 	}
 	
+	/**
+	 * Determine whether or not we'll need to revert the value.
+	 */
+	public boolean isCurrentSet() {
+		return currentSet;
+	}
+	
 	private void ensureLoaded() {
 		// Load the value if we haven't already
 		if (!previousLoaded) {