From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Spottedleaf <Spottedleaf@users.noreply.github.com>
Date: Sat, 5 Mar 2022 17:12:52 -0800
Subject: [PATCH] Fix save problems on shutdown

- Save level.dat first, in case the shutdown is killed later
- Force run minecraftserver tasks and the chunk source tasks
  while waiting for the chunk system to empty, as there's simply
  too much trash that could prevent them from executing during
  the chunk source tick (i.e "time left in tick" logic).
- Set forceTicks to true, so that player packets are always
  processed so that the main process queue can be drained

diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index b37c8c5801b87a24cd26675c3bf4bd2c83c9ba2c..19640c290eb16c9e5afc842ec8ccac5a6a2ea4c7 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -953,6 +953,13 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
             }
         }
 
+        // Paper start - let's be a little more intelligent around crashes
+        // make sure level.dat saves
+        for (ServerLevel level : this.getAllLevels()) {
+            level.saveLevelDat();
+        }
+        // Paper end - let's be a little more intelligent around crashes
+
         while (this.levels.values().stream().anyMatch((worldserver1) -> {
             return worldserver1.getChunkSource().chunkMap.hasWork();
         })) {
@@ -965,9 +972,11 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
                 worldserver.getChunkSource().tick(() -> {
                     return true;
                 }, false);
+                while (worldserver.getChunkSource().pollTask()); // Paper - drain tasks
             }
 
-            this.waitUntilNextTick();
+            this.forceTicks = true; // Paper
+            while (this.pollTask()); // Paper - drain tasks
         }
 
         this.saveAllChunks(false, true, false);
@@ -1264,6 +1273,11 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
     }
 
     private boolean haveTime() {
+        // Paper start
+        if (this.forceTicks) {
+            return true;
+        }
+        // Paper end
         // CraftBukkit start
         if (isOversleep) return canOversleep();// Paper - because of our changes, this logic is broken
         return this.forceTicks || this.runningTask() || Util.getMillis() < (this.mayHaveDelayedTasks ? this.delayedTasksMaxNextTickTime : this.nextTickTime);
diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
index a127865e4aeaba4ab4d25b442f66497bd615a858..852bd159f122826b8cc3f8c4e89f87eba399fffd 100644
--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
+++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
@@ -1272,7 +1272,13 @@ public class ServerLevel extends Level implements WorldGenLevel {
             }
 
         }
+        // Paper start
+        this.saveLevelDat();
+    }
 
+    public void saveLevelDat() {
+        this.saveLevelData();
+        // Paper end
         // CraftBukkit start - moved from MinecraftServer.saveChunks
         ServerLevel worldserver1 = this;