network utility

src/main/java/turniplabs/halplibe/helper/NetworkHelper.java

@@ -0,0 +1,99 @@
+package turniplabs.halplibe.helper;
+
+import net.minecraft.core.net.packet.Packet;
+import org.jetbrains.annotations.NotNull;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+import java.util.Map;
+import java.util.TreeSet;
+import java.util.function.Consumer;
+
+public class NetworkHelper {
+    private static final TreeSet<NetworkEntry> ENTRIES = new TreeSet<>();
+
+    private static boolean locked = false;
+
+    public static void register(Class<Packet> clazz, boolean toServer, boolean toClient) {
+        if (locked)
+            // if a packet is registered after the game starts, the game will most likely crash due to int[]'s in network managers not being long enough
+            throw new RuntimeException("Packet " + clazz + " was registered too late, packets should be registered before the game starts running.");
+        ENTRIES.add(new NetworkEntry(clazz, toServer, toClient));
+    }
+
+    public static void iterateEntries(Consumer<NetworkEntry> consumer) {
+        ENTRIES.forEach(consumer);
+    }
+
+    public static int getLastPacketId() {
+        return lastPacket;
+    }
+
+    // this class is likely more or less redundant, I'm just using it to try to minimize issues from mod load ordering
+    public static final class NetworkEntry implements Comparable<NetworkEntry> {
+        public final Class<Packet> clazz;
+
+        public final boolean toServer, toClient;
+
+        public NetworkEntry(Class<Packet> clazz, boolean toServer, boolean toClient) {
+            this.clazz = clazz;
+            this.toServer = toServer;
+            this.toClient = toClient;
+        }
+
+        @Override
+        public int compareTo(@NotNull NetworkEntry o) {
+            String mname = clazz.getName();
+            String oname = o.clazz.getName();
+
+            int v = Integer.compare(mname.length(), oname.length());
+
+            if (v == 0) {
+                for (int i = 0; i < mname.length(); i++) {
+                    v = Character.compare(mname.charAt(i), oname.charAt(i));
+                    if (v != 0) break;
+                }
+            }
+
+            return v;
+        }
+    }
+
+    private static int latestId = 0;
+    private static int lastPacket = 0;
+
+    private static final Map<Integer, Class<? extends Packet>> map;
+    private static final Method addMapping;
+
+    static {
+        try {
+            Field f = Packet.class.getDeclaredField("packetIdToClassMap");
+            f.setAccessible(true);
+
+            map = (Map<Integer, Class<? extends Packet>>) f.get(null);
+            for (Integer integer : map.keySet())
+                lastPacket = Math.max(integer, lastPacket);
+
+            f.setAccessible(false);
+
+            addMapping = Packet.class.getDeclaredMethod("addIdClassMapping", int.class, boolean.class, boolean.class, Class.class);
+        } catch (Throwable err) {
+            throw new RuntimeException(err);
+        }
+    }
+
+    @SuppressWarnings("unused")
+    private static void doRegister(Class<? extends Packet> packet, boolean server, boolean client) {
+        try {
+            while (map.containsKey(latestId)) latestId++;
+            if (lastPacket < latestId) lastPacket = latestId;
+
+            addMapping.setAccessible(true);
+            addMapping.invoke(null, latestId, client, server, packet);
+            addMapping.setAccessible(false);
+
+            locked = true;
+        } catch (Throwable ignored) {
+        }
+    }
+}

src/main/java/turniplabs/halplibe/mixin/mixins/network/MinecraftMixin.java

@@ -0,0 +1,27 @@
+package turniplabs.halplibe.mixin.mixins.network;
+
+import net.minecraft.client.Minecraft;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+import turniplabs.halplibe.helper.NetworkHelper;
+
+import java.lang.reflect.Method;
+
+@Mixin(value = Minecraft.class, remap = false)
+public class MinecraftMixin {
+    @Inject(at = @At("HEAD"), method = "run")
+    public void postStartClient(CallbackInfo ci) {
+        NetworkHelper.iterateEntries((e) -> {
+            try {
+                Method m = NetworkHelper.class.getDeclaredMethod("doRegister", Class.class, boolean.class, boolean.class);
+                m.setAccessible(true);
+                m.invoke(null, e.clazz, e.toServer, e.toClient);
+                m.setAccessible(false);
+            } catch (Throwable err) {
+                err.printStackTrace();
+            }
+        });
+    }
+}

src/main/java/turniplabs/halplibe/mixin/mixins/network/MinecraftServerMixin.java

@@ -0,0 +1,27 @@
+package turniplabs.halplibe.mixin.mixins.network;
+
+import net.minecraft.server.MinecraftServer;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+import turniplabs.halplibe.helper.NetworkHelper;
+
+import java.lang.reflect.Method;
+
+@Mixin(value = MinecraftServer.class, remap = false)
+public class MinecraftServerMixin {
+    @Inject(at = @At("HEAD"), method = "run")
+    public void postStartClient(CallbackInfo ci) {
+        NetworkHelper.iterateEntries((e) -> {
+            try {
+                Method m = NetworkHelper.class.getDeclaredMethod("doRegister", Class.class, boolean.class, boolean.class);
+                m.setAccessible(true);
+                m.invoke(null, e.clazz, e.toServer, e.toClient);
+                m.setAccessible(false);
+            } catch (Throwable err) {
+                err.printStackTrace();
+            }
+        });
+    }
+}

src/main/java/turniplabs/halplibe/mixin/mixins/network/NetworkManagerMixin.java

@@ -0,0 +1,25 @@
+package turniplabs.halplibe.mixin.mixins.network;
+
+import net.minecraft.core.net.NetworkManager;
+import net.minecraft.core.net.handler.NetHandler;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+import turniplabs.halplibe.helper.NetworkHelper;
+
+import java.net.Socket;
+
+@Mixin(value = NetworkManager.class, remap = false)
+public class NetworkManagerMixin {
+    @Shadow public static int[] field_28144_e;
+
+    @Shadow public static int[] field_28145_d;
+
+    @Inject(at = @At("TAIL"), method = "<init>")
+    public void postInit(Socket socket, String s, NetHandler nethandler, CallbackInfo ci) {
+        field_28144_e = new int[NetworkHelper.getLastPacketId()];
+        field_28145_d = new int[NetworkHelper.getLastPacketId()];
+    }
+}

src/main/java/turniplabs/halplibe/mixin/mixins/network/PacketMixin.java

@@ -0,0 +1,26 @@
+package turniplabs.halplibe.mixin.mixins.network;
+
+import net.minecraft.core.net.packet.Packet;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Redirect;
+import turniplabs.halplibe.helper.NetworkHelper;
+
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+@Mixin(value = Packet.class, remap = false)
+public class PacketMixin {
+    @Redirect(at = @At(value = "INVOKE", target = "Ljava/io/DataOutputStream;write(I)V"), method = "writePacket")
+    private static void preWrite(DataOutputStream instance, int b) throws IOException {
+        if (NetworkHelper.getLastPacketId() > 255) instance.writeInt(b);
+        else instance.write(b);
+    }
+
+    @Redirect(at = @At(value = "INVOKE", target = "Ljava/io/DataInputStream;read()I"), method = "readPacket")
+    private static int preWrite(DataInputStream instance) throws IOException {
+        if (NetworkHelper.getLastPacketId() > 255) return instance.readInt();
+        else return instance.read();
+    }
+}

src/main/resources/halplibe.mixins.json

@@ -22,9 +22,13 @@
     "mixins.GuiIngameMenuMixin",
     "mixins.I18nMixin",
     "mixins.RenderEngineMixin",
-    "mixins.RenderGlobalMixin"
+    "mixins.RenderGlobalMixin",
+    "mixins.network.MinecraftServerMixin",
+    "mixins.network.NetworkManagerMixin",
+    "mixins.network.PacketMixin"
   ],
   "client": [
+    "mixins.network.MinecraftMixin"
   ],
   "injectors": {
     "defaultRequire": 1