PaperMC/patches/server/0887-Array-backed-synched-entity-data.patch
Owen 89d51d5f29
Allow enabling sand duping (#10191)
Because this exploit has been widely known for years and has not been fixed by Mojang, we decided that it was worth allowing people to toggle it on/off due to how easy it is to make it configurable.

It should be noted that this decision does not promise all future exploits will be configurable.
2024-03-03 17:05:34 -05:00

56 lines
2.7 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: jellysquid3 <jellysquid3@users.noreply.github.com>
Date: Sat, 8 Jul 2023 21:38:05 +0200
Subject: [PATCH] Array backed synched entity data
Original code by jellysquid3 in Lithium, licensed under the GNU Lesser General Public License v3.0 (https://www.gnu.org/licenses/lgpl-3.0.html)
diff --git a/src/main/java/net/minecraft/network/syncher/SynchedEntityData.java b/src/main/java/net/minecraft/network/syncher/SynchedEntityData.java
index d088479d160dbd2fc90b48a30553be141db8eef2..07a362f9e485d0d507f16f1dda1ac84ade07ab27 100644
--- a/src/main/java/net/minecraft/network/syncher/SynchedEntityData.java
+++ b/src/main/java/net/minecraft/network/syncher/SynchedEntityData.java
@@ -34,6 +34,11 @@ public class SynchedEntityData {
private final Int2ObjectMap<SynchedEntityData.DataItem<?>> itemsById = new Int2ObjectOpenHashMap();
// private final ReadWriteLock lock = new ReentrantReadWriteLock(); // Spigot - not required
private boolean isDirty;
+ // Paper start - Perf: array backed synched entity data
+ private static final int DEFAULT_ENTRY_COUNT = 10;
+ private static final int GROW_FACTOR = 8;
+ private SynchedEntityData.DataItem<?>[] itemsArray = new SynchedEntityData.DataItem<?>[DEFAULT_ENTRY_COUNT];
+ // Paper end - Perf: array backed synched entity data
public SynchedEntityData(Entity trackedEntity) {
this.entity = trackedEntity;
@@ -103,6 +108,15 @@ public class SynchedEntityData {
// this.lock.writeLock().lock(); // Spigot - not required
this.itemsById.put(key.getId(), datawatcher_item);
// this.lock.writeLock().unlock(); // Spigot - not required
+ // Paper start - Perf: array backed synched entity data
+ if (this.itemsArray.length <= key.getId()) {
+ final int newSize = Math.min(key.getId() + GROW_FACTOR, MAX_ID_VALUE);
+
+ this.itemsArray = java.util.Arrays.copyOf(this.itemsArray, newSize);
+ }
+
+ this.itemsArray[key.getId()] = datawatcher_item;
+ // Paper end - Perf: array backed synched entity data
}
public <T> boolean hasItem(EntityDataAccessor<T> key) {
@@ -130,7 +144,15 @@ public class SynchedEntityData {
return datawatcher_item;
*/
- return (SynchedEntityData.DataItem) this.itemsById.get(key.getId());
+ // Paper start - Perf: array backed synched entity data
+ final int id = key.getId();
+
+ if (id < 0 || id >= this.itemsArray.length) {
+ return null;
+ }
+
+ return (DataItem<T>) this.itemsArray[id];
+ // Paper end - Perf: array backed synched entity data
// Spigot end
}