1 files changed, 118 insertions, 0 deletions
diff --git a/patches/server/0047-Ensure-commands-are-not-ran-async.patch b/patches/server/0047-Ensure-commands-are-not-ran-async.patch
new file mode 100644
index 0000000000..242409c33e
--- /dev/null
+++ b/patches/server/0047-Ensure-commands-are-not-ran-async.patch
@@ -0,0 +1,118 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Aikar <[email protected]>
+Date: Thu, 3 Mar 2016 01:17:12 -0600
+Subject: [PATCH] Ensure commands are not ran async
+
+Plugins calling Player.chat("/foo") or Server.dispatchCommand() could
+trigger the server to execute a command while on another thread.
+
+These commands would then process EXPECTING to be on the main thread, leaving to
+very hard to trace concurrency issues.
+
+This change will synchronize the command execution back to the main thread, causing a
+big slowdown in execution but throwing an exception at same time to raise awareness
+that it is happening so that plugin authors can fix their code to stop executing commands async.
+
+diff --git a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+index 9b47d8ab57c3b290173247ba25ad7668f3529903..6f99b1b54fe893240143282563cb59e6c9cd4122 100644
+--- a/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
++++ b/src/main/java/net/minecraft/server/network/ServerGamePacketListenerImpl.java
+@@ -1871,6 +1871,29 @@ public class ServerGamePacketListenerImpl implements ServerPlayerConnection, Ser
+         }
+ 
+         if (!async && s.startsWith("/")) {
++            // Paper Start
++            if (!org.spigotmc.AsyncCatcher.shuttingDown && !org.bukkit.Bukkit.isPrimaryThread()) {
++                final String fCommandLine = s;
++                LOGGER.error("Command Dispatched Async: " + fCommandLine);
++                LOGGER.error("Please notify author of plugin causing this execution to fix this bug! see: http://bit.ly/1oSiM6C", new Throwable());
++                Waitable wait = new Waitable() {
++                    @Override
++                    protected Object evaluate() {
++                        chat(fCommandLine, false);
++                        return null;
++                    }
++                };
++                server.processQueue.add(wait);
++                try {
++                    wait.get();
++                    return;
++                } catch (InterruptedException e) {
++                    Thread.currentThread().interrupt(); // This is proper habit for java. If we aren't handling it, pass it on!
++                } catch (Exception e) {
++                    throw new RuntimeException("Exception processing chat command", e.getCause());
++                }
++            }
++            // Paper End
+             this.handleCommand(s);
+         } else if (this.player.getChatVisibility() == ChatVisiblity.SYSTEM) {
+             // Do nothing, this is coming from a plugin
+diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+index 3636921da74f5271a15d79d431c8a33a2c83cd96..8df959195e8d516d7f6d90d79c151e8ff5d8bff5 100644
+--- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
++++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+@@ -856,6 +856,28 @@ public final class CraftServer implements Server {
+         Validate.notNull(commandLine, "CommandLine cannot be null");
+         org.spigotmc.AsyncCatcher.catchOp("command dispatch"); // Spigot
+ 
++        // Paper Start
++        if (!org.spigotmc.AsyncCatcher.shuttingDown && !Bukkit.isPrimaryThread()) {
++            final CommandSender fSender = sender;
++            final String fCommandLine = commandLine;
++            Bukkit.getLogger().log(Level.SEVERE, "Command Dispatched Async: " + commandLine);
++            Bukkit.getLogger().log(Level.SEVERE, "Please notify author of plugin causing this execution to fix this bug! see: http://bit.ly/1oSiM6C", new Throwable());
++            org.bukkit.craftbukkit.util.Waitable<Boolean> wait = new org.bukkit.craftbukkit.util.Waitable<Boolean>() {
++                @Override
++                protected Boolean evaluate() {
++                    return dispatchCommand(fSender, fCommandLine);
++                }
++            };
++            net.minecraft.server.MinecraftServer.getServer().processQueue.add(wait);
++            try {
++                return wait.get();
++            } catch (InterruptedException e) {
++                Thread.currentThread().interrupt(); // This is proper habit for java. If we aren't handling it, pass it on!
++            } catch (Exception e) {
++                throw new RuntimeException("Exception processing dispatch command", e.getCause());
++            }
++        }
++        // Paper End
+         if (this.commandMap.dispatch(sender, commandLine)) {
+             return true;
+         }
+diff --git a/src/main/java/org/bukkit/craftbukkit/util/ServerShutdownThread.java b/src/main/java/org/bukkit/craftbukkit/util/ServerShutdownThread.java
+index 19c44daaa407b7c1c7a7ffe56fef8c8814c6d5b2..6a073a9dc44d93eba296a0e18a9c7be8a7881725 100644
+--- a/src/main/java/org/bukkit/craftbukkit/util/ServerShutdownThread.java
++++ b/src/main/java/org/bukkit/craftbukkit/util/ServerShutdownThread.java
+@@ -13,6 +13,7 @@ public class ServerShutdownThread extends Thread {
+     public void run() {
+         try {
+             org.spigotmc.AsyncCatcher.enabled = false; // Spigot
++            org.spigotmc.AsyncCatcher.shuttingDown = true; // Paper
+             this.server.close();
+         } finally {
+             try {
+diff --git a/src/main/java/org/spigotmc/AsyncCatcher.java b/src/main/java/org/spigotmc/AsyncCatcher.java
+index 78669fa035b7537ff7e533cf32aaf2995625424f..7585a30e8f063ac2656b5de519b1e9edaceffbc7 100644
+--- a/src/main/java/org/spigotmc/AsyncCatcher.java
++++ b/src/main/java/org/spigotmc/AsyncCatcher.java
+@@ -6,6 +6,7 @@ public class AsyncCatcher
+ {
+ 
+     public static boolean enabled = true;
++    public static boolean shuttingDown = false; // Paper
+ 
+     public static void catchOp(String reason)
+     {
+diff --git a/src/main/java/org/spigotmc/RestartCommand.java b/src/main/java/org/spigotmc/RestartCommand.java
+index 882e93ad4471e3688f2fcfb1e6f16926786ee5e7..94d8ba376cd1f024b244654cac9bb62bb19e3060 100644
+--- a/src/main/java/org/spigotmc/RestartCommand.java
++++ b/src/main/java/org/spigotmc/RestartCommand.java
+@@ -43,6 +43,7 @@ public class RestartCommand extends Command
+     private static void restart(final String restartScript)
+     {
+         AsyncCatcher.enabled = false; // Disable async catcher incase it interferes with us
++        org.spigotmc.AsyncCatcher.shuttingDown = true; // Paper
+         try
+         {
+             String[] split = restartScript.split( " " );