PaperMC/Remapped-Spigot-Server-Patches/0099-Optimize-UserCache-Thread-Safe.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Mon, 16 May 2016 20:47:41 -0400
Subject: [PATCH] Optimize UserCache / Thread Safe

Because Techable keeps complaining about how this isn't thread safe,
easier to do this than replace the entire thing.

Additionally, move Saving of the User cache to be done async, incase
the user never changed the default setting for Spigot's save on stop only.

diff --git a/src/main/java/net/minecraft/server/MinecraftServer.java b/src/main/java/net/minecraft/server/MinecraftServer.java
index 4e468cb7ccf683b8fc9e04a48cfc25779775e25f..211251fe7cd08074c040df2f4642f37d5f90d856 100644
--- a/src/main/java/net/minecraft/server/MinecraftServer.java
+++ b/src/main/java/net/minecraft/server/MinecraftServer.java
@@ -905,7 +905,7 @@ public abstract class MinecraftServer extends ReentrantBlockableEventLoop<TickTa
         } catch (java.lang.InterruptedException ignored) {} // Paper
         if (org.spigotmc.SpigotConfig.saveUserCacheOnStopOnly) {
             LOGGER.info("Saving usercache.json");
-            this.getProfileCache().save();
+            this.getProfileCache().b(false); // Paper
         }
         // Spigot end
 
diff --git a/src/main/java/net/minecraft/server/dedicated/DedicatedServer.java b/src/main/java/net/minecraft/server/dedicated/DedicatedServer.java
index c7655883262f122b373ac30a33ddb4c06cd9aebe..77616b5dd3d79221d3460b1db4d90ad37c0f85aa 100644
--- a/src/main/java/net/minecraft/server/dedicated/DedicatedServer.java
+++ b/src/main/java/net/minecraft/server/dedicated/DedicatedServer.java
@@ -248,7 +248,7 @@ public class DedicatedServer extends MinecraftServer implements ServerInterface
         }
 
         if (this.convertOldUsers()) {
-            this.getProfileCache().save();
+            this.getProfileCache().b(false); // Paper
         }
 
         if (!OldUsersConverter.serverReadyAfterUserconversion(this)) {
diff --git a/src/main/java/net/minecraft/server/players/GameProfileCache.java b/src/main/java/net/minecraft/server/players/GameProfileCache.java
index 6f37f718015000a3df7e5aa2d7b89bdc283a807b..9342fa6b28e805743b8e3a13007605934244d6cd 100644
--- a/src/main/java/net/minecraft/server/players/GameProfileCache.java
+++ b/src/main/java/net/minecraft/server/players/GameProfileCache.java
@@ -36,6 +36,7 @@ import java.util.concurrent.atomic.AtomicLong;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.stream.Stream;
 import javax.annotation.Nullable;
+import net.minecraft.server.MCUtil;
 import net.minecraft.world.entity.player.Player;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -108,7 +109,7 @@ public class GameProfileCache {
         return GameProfileCache.usesAuthentication;
     }
 
-    public void add(GameProfile gameprofile) {
+    public synchronized void add(GameProfile gameprofile) { // Paper - synchronize
         Calendar calendar = Calendar.getInstance();
 
         calendar.setTime(new Date());
@@ -117,7 +118,7 @@ public class GameProfileCache {
         GameProfileCache.GameProfileInfo usercache_usercacheentry = new GameProfileCache.GameProfileInfo(gameprofile, date);
 
         this.safeAdd(usercache_usercacheentry);
-        if( !org.spigotmc.SpigotConfig.saveUserCacheOnStopOnly ) this.save(); // Spigot - skip saving if disabled
+        if( !org.spigotmc.SpigotConfig.saveUserCacheOnStopOnly ) this.b(true); // Spigot - skip saving if disabled // Paper - async
     }
 
     private long getNextOperation() {
@@ -125,7 +126,7 @@ public class GameProfileCache {
     }
 
     @Nullable
-    public GameProfile get(String s) {
+    public synchronized GameProfile get(String s) { // Paper - synchronize
         String s1 = s.toLowerCase(Locale.ROOT);
         GameProfileCache.GameProfileInfo usercache_usercacheentry = (GameProfileCache.GameProfileInfo) this.profilesByName.get(s1);
         boolean flag = false;
@@ -151,7 +152,7 @@ public class GameProfileCache {
         }
 
         if (flag && !org.spigotmc.SpigotConfig.saveUserCacheOnStopOnly) { // Spigot - skip saving if disabled
-            this.save();
+            this.b(true); // Paper
         }
 
         return gameprofile;
@@ -233,7 +234,7 @@ public class GameProfileCache {
         return arraylist;
     }
 
-    public void save() {
+    public void b(boolean asyncSave) { // Paper
         JsonArray jsonarray = new JsonArray();
         DateFormat dateformat = createDateFormat();
 
@@ -241,6 +242,7 @@ public class GameProfileCache {
             jsonarray.add(writeGameProfile(usercache_usercacheentry, dateformat));
         });
         String s = this.gson.toJson(jsonarray);
+        Runnable save = () -> { // Paper
 
         try {
             BufferedWriter bufferedwriter = Files.newWriter(this.file, StandardCharsets.UTF_8);
@@ -268,6 +270,14 @@ public class GameProfileCache {
         } catch (IOException ioexception) {
             ;
         }
+        // Paper start
+        };
+        if (asyncSave) {
+            MCUtil.scheduleAsyncTask(save);
+        } else {
+            save.run();
+        }
+        // Paper end
 
     }