Paper/CraftBukkit-Patches/0008-Async-Operation-Catching.patch

From e028f1d959724a25798c37587be731d57f9923dd Mon Sep 17 00:00:00 2001
From: md_5 <git@md-5.net>
Date: Tue, 25 Mar 2014 16:10:01 +1100
Subject: [PATCH] Async Operation Catching

Catch and throw an exception when a potentially unsafe operation occurs on a thread other than the main server thread.

diff --git a/src/main/java/net/minecraft/server/Block.java b/src/main/java/net/minecraft/server/Block.java
index 12589d6..1d2f580 100644
--- a/src/main/java/net/minecraft/server/Block.java
+++ b/src/main/java/net/minecraft/server/Block.java
@@ -274,9 +274,13 @@ public class Block {
         return 10;
     }
 
-    public void onPlace(World world, BlockPosition blockposition, IBlockData iblockdata) {}
+    public void onPlace(World world, BlockPosition blockposition, IBlockData iblockdata) {
+        org.spigotmc.AsyncCatcher.catchOp( "block onPlace"); // Spigot
+    }
 
-    public void remove(World world, BlockPosition blockposition, IBlockData iblockdata) {}
+    public void remove(World world, BlockPosition blockposition, IBlockData iblockdata) {
+        org.spigotmc.AsyncCatcher.catchOp( "block remove"); // Spigot
+    }
 
     public int a(Random random) {
         return 1;
diff --git a/src/main/java/net/minecraft/server/EntityLiving.java b/src/main/java/net/minecraft/server/EntityLiving.java
index 0c5f269..170b192 100644
--- a/src/main/java/net/minecraft/server/EntityLiving.java
+++ b/src/main/java/net/minecraft/server/EntityLiving.java
@@ -618,6 +618,7 @@ public abstract class EntityLiving extends Entity {
     }
 
     public void addEffect(MobEffect mobeffect) {
+        org.spigotmc.AsyncCatcher.catchOp( "effect add"); // Spigot
         // CraftBukkit start
         if (isTickingEffects) {
             effectsToProcess.add(mobeffect);
diff --git a/src/main/java/net/minecraft/server/EntityTracker.java b/src/main/java/net/minecraft/server/EntityTracker.java
index ed9b0e5..0c19e5a 100644
--- a/src/main/java/net/minecraft/server/EntityTracker.java
+++ b/src/main/java/net/minecraft/server/EntityTracker.java
@@ -102,6 +102,7 @@ public class EntityTracker {
     }
 
     public void addEntity(Entity entity, int i, final int j, boolean flag) {
+        org.spigotmc.AsyncCatcher.catchOp( "entity track"); // Spigot
         try {
             if (this.trackedEntities.b(entity.getId())) {
                 throw new IllegalStateException("Entity is already tracked!");
@@ -146,6 +147,7 @@ public class EntityTracker {
     }
 
     public void untrackEntity(Entity entity) {
+        org.spigotmc.AsyncCatcher.catchOp( "entity untrack"); // Spigot
         if (entity instanceof EntityPlayer) {
             EntityPlayer entityplayer = (EntityPlayer) entity;
             Iterator iterator = this.c.iterator();
diff --git a/src/main/java/net/minecraft/server/EntityTrackerEntry.java b/src/main/java/net/minecraft/server/EntityTrackerEntry.java
index 8b38bd2..f8570a8 100644
--- a/src/main/java/net/minecraft/server/EntityTrackerEntry.java
+++ b/src/main/java/net/minecraft/server/EntityTrackerEntry.java
@@ -324,6 +324,7 @@ public class EntityTrackerEntry {
     }
 
     public void updatePlayer(EntityPlayer entityplayer) {
+        org.spigotmc.AsyncCatcher.catchOp( "player tracker update"); // Spigot
         if (entityplayer != this.tracker) {
             if (this.c(entityplayer)) {
                 if (!this.trackedPlayers.contains(entityplayer) && (this.e(entityplayer) || this.tracker.attachedToPlayer)) {
@@ -558,6 +559,7 @@ public class EntityTrackerEntry {
     }
 
     public void clear(EntityPlayer entityplayer) {
+        org.spigotmc.AsyncCatcher.catchOp( "player tracker clear"); // Spigot
         if (this.trackedPlayers.contains(entityplayer)) {
             this.trackedPlayers.remove(entityplayer);
             this.tracker.c(entityplayer);
diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index 1ee65dd..79b0c43 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -897,6 +897,7 @@ public abstract class World implements IBlockAccess {
     }
 
     public boolean addEntity(Entity entity, SpawnReason spawnReason) { // Changed signature, added SpawnReason
+        org.spigotmc.AsyncCatcher.catchOp( "entity add"); // Spigot
         if (entity == null) return false;
         // CraftBukkit end
         int i = MathHelper.floor(entity.locX / 16.0D);
@@ -1003,6 +1004,7 @@ public abstract class World implements IBlockAccess {
     }
 
     public void removeEntity(Entity entity) {
+        org.spigotmc.AsyncCatcher.catchOp( "entity remove"); // Spigot
         entity.b(false);
         entity.die();
         if (entity instanceof EntityHuman) {
@@ -2446,6 +2448,7 @@ public abstract class World implements IBlockAccess {
     }
 
     public void a(Collection<Entity> collection) {
+        org.spigotmc.AsyncCatcher.catchOp( "entity world add"); // Spigot
         // CraftBukkit start
         // this.entityList.addAll(collection);
         Iterator iterator = collection.iterator();
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
index f85bf83..10e321f 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftWorld.java
@@ -166,6 +166,7 @@ public class CraftWorld implements World {
     }
 
     public boolean unloadChunkRequest(int x, int z, boolean safe) {
+        org.spigotmc.AsyncCatcher.catchOp( "chunk unload"); // Spigot
         if (safe && isChunkInUse(x, z)) {
             return false;
         }
@@ -176,6 +177,7 @@ public class CraftWorld implements World {
     }
 
     public boolean unloadChunk(int x, int z, boolean save, boolean safe) {
+        org.spigotmc.AsyncCatcher.catchOp( "chunk unload"); // Spigot
         if (safe && isChunkInUse(x, z)) {
             return false;
         }
@@ -258,6 +260,7 @@ public class CraftWorld implements World {
     }
 
     public boolean loadChunk(int x, int z, boolean generate) {
+        org.spigotmc.AsyncCatcher.catchOp( "chunk load"); // Spigot
         chunkLoadCount++;
         if (generate) {
             // Use the default variant of loadChunk when generate == true.
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
index 01ba89f..e93cedb 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
@@ -211,6 +211,7 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
 
     @Override
     public void kickPlayer(String message) {
+        org.spigotmc.AsyncCatcher.catchOp( "player kick"); // Spigot
         if (getHandle().playerConnection == null) return;
 
         getHandle().playerConnection.disconnect(message == null ? "" : message);
diff --git a/src/main/java/org/bukkit/craftbukkit/scoreboard/CraftScoreboardManager.java b/src/main/java/org/bukkit/craftbukkit/scoreboard/CraftScoreboardManager.java
index db4c1db..12768ed 100644
--- a/src/main/java/org/bukkit/craftbukkit/scoreboard/CraftScoreboardManager.java
+++ b/src/main/java/org/bukkit/craftbukkit/scoreboard/CraftScoreboardManager.java
@@ -42,6 +42,7 @@ public final class CraftScoreboardManager implements ScoreboardManager {
     }
 
     public CraftScoreboard getNewScoreboard() {
+        org.spigotmc.AsyncCatcher.catchOp( "scoreboard creation"); // Spigot
         CraftScoreboard scoreboard = new CraftScoreboard(new ScoreboardServer(server));
         scoreboards.add(scoreboard);
         return scoreboard;
diff --git a/src/main/java/org/spigotmc/AsyncCatcher.java b/src/main/java/org/spigotmc/AsyncCatcher.java
new file mode 100644
index 0000000..4b3aa85
--- /dev/null
+++ b/src/main/java/org/spigotmc/AsyncCatcher.java
@@ -0,0 +1,17 @@
+package org.spigotmc;
+
+import net.minecraft.server.MinecraftServer;
+
+public class AsyncCatcher
+{
+
+    public static boolean enabled = true;
+
+    public static void catchOp(String reason)
+    {
+        if ( enabled && Thread.currentThread() != MinecraftServer.getServer().primaryThread )
+        {
+            throw new IllegalStateException( "Asynchronous " + reason + "!" );
+        }
+    }
+}
-- 
2.5.0