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 330b965bcf4740743d131d28b0ff72ba257b2bce..104428d032721fc488c2931c06e802e9b00e47bd 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -954,6 +954,13 @@ 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();
         })) {
@@ -966,9 +973,11 @@ 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);
@@ -1265,6 +1274,11 @@ 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 b021fc77687cf7f569e5bf6fbb481c486e27e5a6..c89e85c1fe37c8fba54825be76bb1caa15d84dcd 100644
--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
+++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
@@ -1278,7 +1278,13 @@ 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;