From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Cryptite <cryptite@gmail.com>
Date: Mon, 12 Jun 2023 14:09:36 -0500
Subject: [PATCH] Shared Data Storage


diff --git a/src/main/java/io/papermc/paper/configuration/GlobalConfiguration.java b/src/main/java/io/papermc/paper/configuration/GlobalConfiguration.java
index 4ac3fa45cd155ae8a852e26d4d4d1f16b28efdc2..b89e3568cc9371984fe1cd8f83008a9250956465 100644
--- a/src/main/java/io/papermc/paper/configuration/GlobalConfiguration.java
+++ b/src/main/java/io/papermc/paper/configuration/GlobalConfiguration.java
@@ -270,6 +270,7 @@ public class GlobalConfiguration extends ConfigurationPart {
         public boolean lagCompensateBlockBreaking = true;
         public boolean useDimensionTypeForCustomSpawners = false;
         public boolean strictAdvancementDimensionCheck = false;
+        public String sharedDataFolder = "";
     }
 
     public BlockUpdates blockUpdates;
diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 681123682c1a0060d05860835e5b9f46147f7c1f..619956817b5fccb74a6d68d5e3ea1b317c69b779 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -2,6 +2,7 @@ package net.minecraft.server;
 
 import com.google.common.base.Preconditions;
 import com.google.common.base.Splitter;
+import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
 import co.aikar.timings.Timings;
 import com.destroystokyo.paper.event.server.PaperServerListPingEvent;
@@ -311,6 +312,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
     public volatile Thread shutdownThread; // Paper
     public volatile boolean abnormalExit = false; // Paper
     public boolean isIteratingOverLevels = false; // Paper
+    public @Nullable DimensionDataStorage sharedDataStorage; // Slice
 
     public static <S extends MinecraftServer> S spin(Function<Thread, S> serverFactory) {
         AtomicReference<S> atomicreference = new AtomicReference();
@@ -411,6 +413,12 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
     }
     // CraftBukkit end
 
+        // Slice start
+    public DimensionDataStorage getMapDataStorage() {
+        return sharedDataStorage != null ? sharedDataStorage : overworld().getDataStorage();
+    }
+    // Slice end
+
     private void readScoreboard(DimensionDataStorage persistentStateManager) {
         ServerScoreboard scoreboardserver = this.getScoreboard();
 
@@ -886,6 +894,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
             this.isSaving = true;
             this.getPlayerList().saveAll(); // Diff on change
             flag3 = this.saveAllChunks(suppressLogs, flush, force);
+            if (sharedDataStorage != null) sharedDataStorage.save(); // Slice
         } finally {
             this.isSaving = false;
         }
@@ -1102,6 +1111,15 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
                 throw new IllegalStateException("Failed to initialize server");
             }
 
+            // Slice start
+            String sharedDataFolder = io.papermc.paper.configuration.GlobalConfiguration.get().misc.sharedDataFolder;
+            if (!Strings.isNullOrEmpty(sharedDataFolder)) {
+                File sharedDir = new File(sharedDataFolder);
+                sharedDir.mkdirs();
+                this.sharedDataStorage = new DimensionDataStorage(sharedDir, fixerUpper);
+            }
+            // Slice end
+
             this.nextTickTime = Util.getMillis();
             this.statusIcon = (ServerStatus.Favicon) this.loadStatusIcon().orElse(null); // CraftBukkit - decompile error
             this.status = this.buildServerStatus();
@@ -1414,6 +1432,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
                     level.saveIncrementally(fullSave);
                 }
             }
+            if (sharedDataStorage != null) sharedDataStorage.save(); // Slice
         } finally {
             this.isSaving = false;
         }
diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
index af0720fb8bd334aac5493121c6373d87421204b4..564591e9f18dd6bb0f76ae4f153adcc0a228d4fa 100644
--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
+++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
@@ -2068,7 +2068,7 @@ public class ServerLevel extends Level implements WorldGenLevel {
     @Override
     public MapItemSavedData getMapData(String id) {
         // CraftBukkit start
-        return (MapItemSavedData) this.getServer().overworld().getDataStorage().get((nbttagcompound) -> {
+        return (MapItemSavedData) this.getServer().getMapDataStorage().get((nbttagcompound) -> { // Slice
             // We only get here when the data file exists, but is not a valid map
             MapItemSavedData newMap = MapItemSavedData.load(nbttagcompound);
             newMap.id = id;
@@ -2082,12 +2082,22 @@ public class ServerLevel extends Level implements WorldGenLevel {
     @Override
     public void setMapData(String id, MapItemSavedData state) {
         state.id = id; // CraftBukkit
-        this.getServer().overworld().getDataStorage().set(id, state);
+        this.getServer().getMapDataStorage().set(id, state); // Slice
     }
 
     @Override
     public int getFreeMapId() {
-        return ((MapIndex) this.getServer().overworld().getDataStorage().computeIfAbsent(MapIndex::load, MapIndex::new, "idcounts")).getFreeAuxValueForMap();
+        // Slice start
+        DimensionDataStorage storage = this.getServer().getMapDataStorage();
+        MapIndex mapIndex = storage.readSavedData(MapIndex::load, "idcounts");
+        if (mapIndex == null) {
+            mapIndex = new MapIndex();
+        }
+        int newId = mapIndex.getFreeAuxValueForMap();
+        storage.set("idcounts", mapIndex);
+        storage.save();
+        return newId;
+        // Slice end
     }
 
     // Paper start - helper function for configurable spawn radius
diff --git a/src/main/java/net/minecraft/world/level/storage/DimensionDataStorage.java b/src/main/java/net/minecraft/world/level/storage/DimensionDataStorage.java
index defe31a5d3aa89a3d18b94f2ff005594e38754b3..637a86e74d633901fdd2f2f1ba6aa4ed49780ead 100644
--- a/src/main/java/net/minecraft/world/level/storage/DimensionDataStorage.java
+++ b/src/main/java/net/minecraft/world/level/storage/DimensionDataStorage.java
@@ -58,7 +58,7 @@ public class DimensionDataStorage {
     }
 
     @Nullable
-    private <T extends SavedData> T readSavedData(Function<CompoundTag, T> readFunction, String id) {
+    public <T extends SavedData> T readSavedData(Function<CompoundTag, T> readFunction, String id) { // Slice private -> public
         try {
             File file = this.getDataFile(id);
             if (file.exists()) {