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 33953cc7afc2616577b768a23a7d4ce0230cf480..869e0b6c8588d751a9b38b713119f888778d3387 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 fb5c42755703ade855ab727c55c8d72456b59141..b4daa19c5bc3c0555c393f17d6f5da7eb7d7bc35 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;