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 583d2deffa819c1aa25e1937a7f709d0d6bab294..c8d56947305c981a3268ce4ae3e975db350ceff2 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -996,6 +996,13 @@ 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();
         })) {
@@ -1008,9 +1015,11 @@ 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);
@@ -1306,6 +1315,11 @@ 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 00e6f60e13f50c727530de37ab9692ad3683c11b..50fd3419deb668dda64b1056f03fb66da55e6960 100644
--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
+++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
@@ -1258,7 +1258,13 @@ 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;
 
