From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Shane Freeder <theboyetronic@gmail.com>
Date: Thu, 18 Feb 2021 20:23:28 +0000
Subject: [PATCH] misc debugging dumps


diff --git a/src/main/java/io/papermc/paper/util/TraceUtil.java b/src/main/java/io/papermc/paper/util/TraceUtil.java
new file mode 100644
index 0000000000000000000000000000000000000000..2d5494d2813b773e60ddba6790b750a9a08f21f8
--- /dev/null
+++ b/src/main/java/io/papermc/paper/util/TraceUtil.java
@@ -0,0 +1,18 @@
+package io.papermc.paper.util;
+
+import org.bukkit.Bukkit;
+
+public final class TraceUtil {
+
+    public static void dumpTraceForThread(Thread thread, String reason) {
+        Bukkit.getLogger().warning(thread.getName() + ": " + reason);
+        StackTraceElement[] trace = thread.getStackTrace();
+        for (StackTraceElement traceElement : trace) {
+            Bukkit.getLogger().warning("\tat " + traceElement);
+        }
+    }
+
+    public static void dumpTraceForThread(String reason) {
+        new Throwable(reason).printStackTrace();
+    }
+}
diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 697ce13c7c32e4badcd171c1e9eefc49620ae525..84c3110ea03f9121fc4ab0aaa80ddad5efe28e5c 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -13,6 +13,7 @@ import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufOutputStream;
 import io.netty.buffer.Unpooled;
 import io.papermc.paper.event.entity.EntityMoveEvent;
+import io.papermc.paper.util.TraceUtil;
 import it.unimi.dsi.fastutil.longs.LongIterator;
 import java.awt.image.BufferedImage;
 import java.io.BufferedWriter;
@@ -855,6 +856,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
     // CraftBukkit start
     private boolean hasStopped = false;
     public volatile boolean hasFullyShutdown = false; // Paper
+    private boolean hasLoggedStop = false; // Paper
     private final Object stopLock = new Object();
     public final boolean hasStopped() {
         synchronized (stopLock) {
@@ -869,6 +871,7 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
             if (hasStopped) return;
             hasStopped = true;
         }
+        if (!hasLoggedStop && isDebugging()) TraceUtil.dumpTraceForThread("Server stopped"); // Paper
         // Paper start - kill main thread, and kill it hard
         shutdownThread = Thread.currentThread();
         org.spigotmc.WatchdogThread.doStop(); // Paper
@@ -985,6 +988,8 @@ public abstract class MinecraftServer extends IAsyncTaskHandlerReentrant<TickTas
     public void safeShutdown(boolean flag, boolean isRestarting) {
         this.isRunning = false;
         this.isRestarting = isRestarting;
+        this.hasLoggedStop = true; // Paper
+        if (isDebugging()) TraceUtil.dumpTraceForThread("Server stopped"); // Paper
         if (flag) {
             try {
                 this.serverThread.join();
diff --git a/src/main/java/org/bukkit/craftbukkit/CraftServer.java b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
index a4755e2cdb40afe6af47435f92963a53d7b719c7..cbac3c96c5d3c1551912f5769bfc50d690519495 100644
--- a/src/main/java/org/bukkit/craftbukkit/CraftServer.java
+++ b/src/main/java/org/bukkit/craftbukkit/CraftServer.java
@@ -18,6 +18,7 @@ import com.mojang.serialization.Lifecycle;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufOutputStream;
 import io.netty.buffer.Unpooled;
+import io.papermc.paper.util.TraceUtil;
 import it.unimi.dsi.fastutil.objects.Object2ObjectLinkedOpenHashMap;
 import java.awt.image.BufferedImage;
 import java.io.File;
@@ -941,6 +942,7 @@ public final class CraftServer implements Server {
                 plugin.getDescription().getName(),
                 "This plugin is not properly shutting down its async tasks when it is being reloaded.  This may cause conflicts with the newly loaded version of the plugin"
             ));
+            if (console.isDebugging()) TraceUtil.dumpTraceForThread(worker.getThread(), "still running"); // Paper
         }
         loadPlugins();
         enablePlugins(PluginLoadOrder.STARTUP);