From 2e02dfd4d8c9d865c9e0b1b5941060486f54607f Mon Sep 17 00:00:00 2001
From: themode <themode@outlook.fr>
Date: Sat, 5 Feb 2022 08:21:19 +0100
Subject: [PATCH] Fix synchronization issue with viewable packets

---
 src/main/java/net/minestom/server/utils/PacketUtils.java | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/main/java/net/minestom/server/utils/PacketUtils.java b/src/main/java/net/minestom/server/utils/PacketUtils.java
index c69493c80..dbe19f717 100644
--- a/src/main/java/net/minestom/server/utils/PacketUtils.java
+++ b/src/main/java/net/minestom/server/utils/PacketUtils.java
@@ -284,7 +284,7 @@ public final class PacketUtils {
             PooledBuffers.registerBuffer(this, buffer);
         }
 
-        private void append(Viewable viewable, ServerPacket serverPacket, Player player) {
+        private synchronized void append(Viewable viewable, ServerPacket serverPacket, Player player) {
             final ByteBuffer framedPacket = createFramedPacket(serverPacket);
             final int packetSize = framedPacket.limit();
             if (packetSize >= buffer.capacity()) {
@@ -307,7 +307,7 @@ public final class PacketUtils {
             }
         }
 
-        private void process(Viewable viewable) {
+        private synchronized void process(Viewable viewable) {
             if (buffer.writerOffset() == 0) return;
             ByteBuffer copy = ByteBuffer.allocateDirect(buffer.writerOffset());
             copy.put(buffer.asByteBuffer(0, copy.capacity()));