Paper/Spigot-Server-Patches/0485-Load-Chunks-for-Login-Asynchronously.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sun, 19 Apr 2020 04:28:29 -0400
Subject: [PATCH] Load Chunks for Login Asynchronously


diff --git a/src/main/java/net/minecraft/server/Entity.java b/src/main/java/net/minecraft/server/Entity.java
index 324fd07bcee9fed7bdb5b2b47ef01ce341282c93..01330045c0f3e0993af66c5a34c2a0246003758b 100644
--- a/src/main/java/net/minecraft/server/Entity.java
+++ b/src/main/java/net/minecraft/server/Entity.java
@@ -1382,7 +1382,7 @@ public abstract class Entity implements INamableTileEntity, ICommandListener, Ke
         this.pitch = MathHelper.a(f1, -90.0F, 90.0F) % 360.0F;
         this.lastYaw = this.yaw;
         this.lastPitch = this.pitch;
-        world.getChunkAt((int) Math.floor(this.locX) >> 4, (int) Math.floor(this.locZ) >> 4); // CraftBukkit
+        if (valid) world.getChunkAt((int) Math.floor(this.locX) >> 4, (int) Math.floor(this.locZ) >> 4); // CraftBukkit // Paper
     }
 
     public void setPositionRotation(BlockPosition blockposition, float f, float f1) {
diff --git a/src/main/java/net/minecraft/server/EntityPlayer.java b/src/main/java/net/minecraft/server/EntityPlayer.java
index 45df816980cd880b257632f0c4a381d475d2dfbd..48bbaec4b64bede8d280bd866436f5528578013e 100644
--- a/src/main/java/net/minecraft/server/EntityPlayer.java
+++ b/src/main/java/net/minecraft/server/EntityPlayer.java
@@ -43,6 +43,7 @@ public class EntityPlayer extends EntityHuman implements ICrafting {
     private static final Logger LOGGER = LogManager.getLogger();
     public String locale = null; // CraftBukkit - lowercase // Paper - default to null
     public PlayerConnection playerConnection;
+    public NetworkManager networkManager; // Paper
     public final MinecraftServer server;
     public final PlayerInteractManager playerInteractManager;
     public final Deque<Integer> removeQueue = new ArrayDeque<>(); // Paper
@@ -101,6 +102,7 @@ public class EntityPlayer extends EntityHuman implements ICrafting {
     public boolean joining = true;
     public boolean sentListPacket = false;
     public boolean supressTrackerForLogin = false; // Paper
+    public boolean didPlayerJoinEvent = false; // Paper
     public Integer clientViewDistance;
     // CraftBukkit end
     public PlayerNaturallySpawnCreaturesEvent playerNaturallySpawnedEvent; // Paper
diff --git a/src/main/java/net/minecraft/server/LoginListener.java b/src/main/java/net/minecraft/server/LoginListener.java
index f1222fcb2bd52b8781d0f92c94e1472fa7b1e493..28f48f22522ef8c3c66381abcf017f0859b45290 100644
--- a/src/main/java/net/minecraft/server/LoginListener.java
+++ b/src/main/java/net/minecraft/server/LoginListener.java
@@ -66,7 +66,7 @@ public class LoginListener implements PacketLoginInListener {
             }
             // Paper end
         } else if (this.g == LoginListener.EnumProtocolState.DELAY_ACCEPT) {
-            EntityPlayer entityplayer = this.server.getPlayerList().a(this.i.getId());
+            EntityPlayer entityplayer = this.server.getPlayerList().getActivePlayer(this.i.getId()); // Paper
 
             if (entityplayer == null) {
                 this.g = LoginListener.EnumProtocolState.READY_TO_ACCEPT;
@@ -165,7 +165,7 @@ public class LoginListener implements PacketLoginInListener {
             }
 
             this.networkManager.sendPacket(new PacketLoginOutSuccess(this.i));
-            EntityPlayer entityplayer = this.server.getPlayerList().a(this.i.getId());
+            EntityPlayer entityplayer = this.server.getPlayerList().getActivePlayer(this.i.getId()); // Paper
 
             if (entityplayer != null) {
                 this.g = LoginListener.EnumProtocolState.DELAY_ACCEPT;
diff --git a/src/main/java/net/minecraft/server/PlayerConnection.java b/src/main/java/net/minecraft/server/PlayerConnection.java
index 2e81f3a1d93d66c94e9f0d425f9cee6db4940913..8800a8fcf9a09aa8cf5555e136734856d0c5b1f4 100644
--- a/src/main/java/net/minecraft/server/PlayerConnection.java
+++ b/src/main/java/net/minecraft/server/PlayerConnection.java
@@ -69,6 +69,7 @@ public class PlayerConnection implements PacketListenerPlayIn {
     private static final Logger LOGGER = LogManager.getLogger();
     public final NetworkManager networkManager;
     private final MinecraftServer minecraftServer;
+    Runnable playerJoinReady; // Paper
     public EntityPlayer player;
     private int e;
     private long lastKeepAlive = SystemUtils.getMonotonicMillis(); private void setLastPing(long lastPing) { this.lastKeepAlive = lastPing;}; private long getLastPing() { return this.lastKeepAlive;}; // Paper - OBFHELPER
@@ -142,6 +143,17 @@ public class PlayerConnection implements PacketListenerPlayIn {
     // CraftBukkit end
 
     public void tick() {
+        // Paper start - login async
+        Runnable playerJoinReady = this.playerJoinReady;
+        if (playerJoinReady != null) {
+            this.playerJoinReady = null;
+            playerJoinReady.run();
+        }
+        // Don't tick if not valid (dead), otherwise we load chunks below
+        if (!this.player.valid) {
+            return;
+        }
+        // Paper end
         this.syncPosition();
         this.player.lastX = this.player.locX();
         this.player.lastY = this.player.locY();
diff --git a/src/main/java/net/minecraft/server/PlayerList.java b/src/main/java/net/minecraft/server/PlayerList.java
index 6a4e4f93eb36ca388523a36abf38bcae3ad375e8..61c7f5f9528ceea34af8dbf4503b9c320b7f67a1 100644
--- a/src/main/java/net/minecraft/server/PlayerList.java
+++ b/src/main/java/net/minecraft/server/PlayerList.java
@@ -52,11 +52,12 @@ public abstract class PlayerList {
     private static final SimpleDateFormat g = new SimpleDateFormat("yyyy-MM-dd 'at' HH:mm:ss z");
     private final MinecraftServer server;
     public final List<EntityPlayer> players = new java.util.concurrent.CopyOnWriteArrayList(); // CraftBukkit - ArrayList -> CopyOnWriteArrayList: Iterator safety
-    private final Map<UUID, EntityPlayer> j = Maps.newHashMap();
+    private final Map<UUID, EntityPlayer> j = Maps.newHashMap();Map<UUID, EntityPlayer> getUUIDMap() { return j; } // Paper - OBFHELPER
     private final GameProfileBanList k;
     private final IpBanList l;
     private final OpList operators;
     private final WhiteList whitelist;
+    private final Map<UUID, EntityPlayer> pendingPlayers = Maps.newHashMap(); // Paper
     // CraftBukkit start
     // private final Map<UUID, ServerStatisticManager> o;
     // private final Map<UUID, AdvancementDataPlayer> p;
@@ -94,6 +95,11 @@ public abstract class PlayerList {
     }
 
     public void a(NetworkManager networkmanager, EntityPlayer entityplayer) {
+        EntityPlayer prev = pendingPlayers.put(entityplayer.getUniqueID(), entityplayer);// Paper
+        if (prev != null) {
+            disconnectPendingPlayer(prev);
+        }
+        entityplayer.networkManager = networkmanager; // Paper
         entityplayer.loginTime = System.currentTimeMillis(); // Paper
         GameProfile gameprofile = entityplayer.getProfile();
         UserCache usercache = this.server.getUserCache();
@@ -107,7 +113,7 @@ public abstract class PlayerList {
         if (nbttagcompound != null && nbttagcompound.hasKey("bukkit")) {
             NBTTagCompound bukkit = nbttagcompound.getCompound("bukkit");
             s = bukkit.hasKeyOfType("lastKnownName", 8) ? bukkit.getString("lastKnownName") : s;
-        }
+        }String lastKnownName = s; // Paper
         if (nbttagcompound == null) entityplayer.moveToSpawn(worldserver); // Paper - only move to spawn on first login, otherwise, stay where you are....
         // CraftBukkit end
 
@@ -160,6 +166,50 @@ public abstract class PlayerList {
         entityplayer.B().a(entityplayer);
         this.sendScoreboard(worldserver.getScoreboard(), entityplayer);
         this.server.invalidatePingSample();
+        // Paper start - async load spawn in chunk
+        WorldServer finalWorldserver = worldserver;
+        int chunkX = loc.getBlockX() >> 4;
+        int chunkZ = loc.getBlockZ() >> 4;
+        worldserver.getChunkProvider().getTickingChunkAsync(chunkX, chunkZ, (chunk -> { // use ticking - as it has at least 1 neighbours loaded
+            playerconnection.playerJoinReady = () -> {
+                postChunkLoadJoin(
+                    entityplayer, finalWorldserver, networkmanager, playerconnection,
+                    nbttagcompound, networkmanager.getSocketAddress().toString(), lastKnownName
+                );
+            };
+        }));
+        // boost the priorities
+        worldserver.asyncChunkTaskManager.raisePriority(chunkX, chunkZ, com.destroystokyo.paper.io.PrioritizedTaskQueue.HIGHEST_PRIORITY);
+        for (int cx = -1; cx <= 1; cx++) {
+            for (int cz = -1; cz <= 1; cz++) {
+                if (cx == 0 && cz == 0) continue;
+                // we have to directly request it otherwise the task won't be started yet to boost priority
+                worldserver.getChunkProvider().getFullChunkAsync(chunkX + cx, chunkZ + cz, null);
+                worldserver.asyncChunkTaskManager.raisePriority(chunkX + cx, chunkZ + cz, com.destroystokyo.paper.io.PrioritizedTaskQueue.HIGHEST_PRIORITY);
+            }
+        }
+    }
+
+    EntityPlayer getActivePlayer(UUID uuid) {
+        EntityPlayer player = this.getUUIDMap().get(uuid);
+        return player != null ? player : pendingPlayers.get(uuid);
+    }
+
+    void disconnectPendingPlayer(EntityPlayer entityplayer) {
+        ChatMessage msg = new ChatMessage("multiplayer.disconnect.duplicate_login", new Object[0]);
+        entityplayer.networkManager.sendPacket(new PacketPlayOutKickDisconnect(msg), (future) -> {
+            entityplayer.networkManager.close(msg);
+            entityplayer.networkManager = null;
+        });
+    }
+
+    private void postChunkLoadJoin(EntityPlayer entityplayer, WorldServer worldserver, NetworkManager networkmanager, PlayerConnection playerconnection, NBTTagCompound nbttagcompound, String s1, String s) {
+        pendingPlayers.remove(entityplayer.getUniqueID(), entityplayer);
+        if (!networkmanager.isConnected()) {
+            return;
+        }
+        entityplayer.didPlayerJoinEvent = true;
+        // Paper end
         ChatMessage chatmessage;
 
         if (entityplayer.getProfile().getName().equalsIgnoreCase(s)) {
@@ -218,7 +268,6 @@ public abstract class PlayerList {
         }
         entityplayer.sentListPacket = true;
         entityplayer.supressTrackerForLogin = false; // Paper
-        ((WorldServer)entityplayer.world).getChunkProvider().playerChunkMap.addEntity(entityplayer); // Paper - track entity now
         // CraftBukkit end
 
         entityplayer.playerConnection.sendPacket(new PacketPlayOutEntityMetadata(entityplayer.getId(), entityplayer.datawatcher, true)); // CraftBukkit - BungeeCord#2321, send complete data to self on spawn
@@ -245,6 +294,7 @@ public abstract class PlayerList {
         }
 
         // Paper start - move vehicle into method so it can be called above - short circuit around that code
+        ((WorldServer)entityplayer.world).getChunkProvider().playerChunkMap.addEntity(entityplayer); // track entity now
         onPlayerJoinFinish(entityplayer, worldserver, s1);
     }
     private void mountSavedVehicle(EntityPlayer entityplayer, WorldServer worldserver, NBTTagCompound nbttagcompound) {
@@ -390,6 +440,7 @@ public abstract class PlayerList {
 
     protected void savePlayerFile(EntityPlayer entityplayer) {
         if (!entityplayer.getBukkitEntity().isPersistent()) return; // CraftBukkit
+        if (!entityplayer.didPlayerJoinEvent) return; // Paper - If we never fired PJE, we disconnected during login. Data has not changed, and additionally, our saved vehicle is not loaded! If we save now, we will lose our vehicle (CraftBukkit bug)
         this.playerFileData.save(entityplayer);
         ServerStatisticManager serverstatisticmanager = (ServerStatisticManager) entityplayer.getStatisticManager(); // CraftBukkit
 
@@ -414,7 +465,7 @@ public abstract class PlayerList {
         org.bukkit.craftbukkit.event.CraftEventFactory.handleInventoryCloseEvent(entityplayer, org.bukkit.event.inventory.InventoryCloseEvent.Reason.DISCONNECT); // Paper
 
         PlayerQuitEvent playerQuitEvent = new PlayerQuitEvent(cserver.getPlayer(entityplayer), "\u00A7e" + entityplayer.getName() + " left the game");
-        cserver.getPluginManager().callEvent(playerQuitEvent);
+        if (entityplayer.didPlayerJoinEvent) cserver.getPluginManager().callEvent(playerQuitEvent); // Paper - if we disconnected before join ever fired, don't fire quit
         entityplayer.getBukkitEntity().disconnect(playerQuitEvent.getQuitMessage());
 
         if (server.isMainThread()) entityplayer.playerTick();// SPIGOT-924 // Paper - don't tick during emergency shutdowns (Watchdog)
@@ -466,6 +517,13 @@ public abstract class PlayerList {
             // this.p.remove(uuid);
             // CraftBukkit end
         }
+        // Paper start
+        entityplayer1 = pendingPlayers.get(uuid);
+        if (entityplayer1 == entityplayer) {
+            pendingPlayers.remove(uuid);
+        }
+        entityplayer.networkManager = null;
+        // Paper end
 
         // CraftBukkit start
         //  this.sendAll(new PacketPlayOutPlayerInfo(EnumPlayerInfoAction.REMOVE_PLAYER, new EntityPlayer[]{entityplayer}));
@@ -483,7 +541,7 @@ public abstract class PlayerList {
         cserver.getScoreboardManager().removePlayer(entityplayer.getBukkitEntity());
         // CraftBukkit end
 
-        return playerQuitEvent.getQuitMessage(); // CraftBukkit
+        return entityplayer.didPlayerJoinEvent ? playerQuitEvent.getQuitMessage() : null; // CraftBukkit // Paper - don't print quit if we never printed join
     }
 
     // CraftBukkit start - Whole method, SocketAddress to LoginListener, added hostname to signature, return EntityPlayer
@@ -502,6 +560,13 @@ public abstract class PlayerList {
                 list.add(entityplayer);
             }
         }
+        // Paper start - check pending players too
+        entityplayer = pendingPlayers.get(uuid);
+        if (entityplayer != null) {
+            this.pendingPlayers.remove(uuid);
+            disconnectPendingPlayer(entityplayer);
+        }
+        // Paper end
 
         Iterator iterator = list.iterator();