Leaf/leaf-server/minecraft-patches/features/0074-Send-multiple-keep-alive-packets.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Martijn Muijsers <martijnmuijsers@live.nl>
Date: Wed, 30 Nov 2022 00:43:42 +0100
Subject: [PATCH] Send multiple keep-alive packets

License: MIT (https://opensource.org/licenses/MIT)
Gale - https://galemc.org

This patch is based on the following patch:
"Alternative Keepalive Handling"
By: William Blake Galbreath <blake.galbreath@gmail.com>
As part of: Purpur (https://github.com/PurpurMC/Purpur)
Licensed under: MIT (https://opensource.org/licenses/MIT)

* Purpur copyright *

MIT License

Copyright (c) 2019-2022 PurpurMC

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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SOFTWARE.

diff --git a/net/minecraft/server/network/ServerCommonPacketListenerImpl.java b/net/minecraft/server/network/ServerCommonPacketListenerImpl.java
index 776ff13b399fa01bf3900280cf1b5782370732a0..c4f4c21f32e2aba79e15315d73124c803bb1223a 100644
--- a/net/minecraft/server/network/ServerCommonPacketListenerImpl.java
+++ b/net/minecraft/server/network/ServerCommonPacketListenerImpl.java
@@ -40,6 +40,7 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
     private long keepAliveChallenge;
     private long closedListenerTime;
     private boolean closed = false;
+    private it.unimi.dsi.fastutil.longs.LongList keepAlives = new it.unimi.dsi.fastutil.longs.LongArrayList(); // Gale - Purpur - send multiple keep-alive packets
     private int latency;
     private volatile boolean suspendFlushingOnServerThread = false;
     // CraftBukkit start
@@ -48,7 +49,10 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
     public boolean processedDisconnect;
     // CraftBukkit end
     public final java.util.Map<java.util.UUID, net.kyori.adventure.resource.ResourcePackCallback> packCallbacks = new java.util.concurrent.ConcurrentHashMap<>(); // Paper - adventure resource pack callbacks
-    private static final long KEEPALIVE_LIMIT = Long.getLong("paper.playerconnection.keepalive", 30) * 1000; // Paper - provide property to set keepalive limit
+    // Gale start - Purpur - send multiple keep-alive packets
+    private static final long KEEPALIVE_LIMIT_IN_SECONDS = Long.getLong("paper.playerconnection.keepalive", 30); // Paper - provide property to set keepalive limit
+    private static final long KEEPALIVE_LIMIT = KEEPALIVE_LIMIT_IN_SECONDS * 1000;
+    // Gale end - Purpur - send multiple keep-alive packets
     protected static final net.minecraft.resources.ResourceLocation MINECRAFT_BRAND = net.minecraft.resources.ResourceLocation.withDefaultNamespace("brand"); // Paper - Brand support
 
     public ServerCommonPacketListenerImpl(MinecraftServer server, Connection connection, CommonListenerCookie cookie, net.minecraft.server.level.ServerPlayer player) { // CraftBukkit
@@ -117,6 +121,16 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
 
     @Override
     public void handleKeepAlive(ServerboundKeepAlivePacket packet) {
+        // Gale start - Purpur - send multiple keep-alive packets
+        if (org.galemc.gale.configuration.GaleGlobalConfiguration.get().misc.keepalive.sendMultiple) {
+            if (this.keepAlivePending && !keepAlives.isEmpty() && keepAlives.contains(packet.getId())) {
+                int ping = (int) (Util.getMillis() - packet.getId());
+                this.latency = (this.latency * 3 + ping) / 4;
+                this.keepAlivePending = false;
+                this.keepAlives.clear(); // We got a valid response, let's roll with it and forget the rest
+            }
+        } else {
+            // Gale end - Purpur - send multiple keep-alive packets
         if (this.keepAlivePending && packet.getId() == this.keepAliveChallenge) {
             int i = (int)(Util.getMillis() - this.keepAliveTime);
             this.latency = (this.latency * 3 + i) / 4;
@@ -124,6 +138,7 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
         } else if (!this.isSingleplayerOwner()) {
             this.disconnectAsync(TIMEOUT_DISCONNECTION_MESSAGE, org.bukkit.event.player.PlayerKickEvent.Cause.TIMEOUT); // Paper - add proper async disconnect
         }
+        } // Gale - Purpur - send multiple keep-alive packets
     }
 
     @Override
@@ -240,6 +255,21 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
         // Paper start - give clients a longer time to respond to pings as per pre 1.12.2 timings
         // This should effectively place the keepalive handling back to "as it was" before 1.12.2
         final long elapsedTime = millis - this.keepAliveTime;
+        // Gale start - Purpur - send multiple keep-alive packets
+        if (org.galemc.gale.configuration.GaleGlobalConfiguration.get().misc.keepalive.sendMultiple) {
+            if (elapsedTime >= 1000L) { // 1 second
+                if (this.keepAlivePending && !this.processedDisconnect && this.keepAlives.size() >= KEEPALIVE_LIMIT_IN_SECONDS) {
+                    LOGGER.warn("{} was kicked due to keepalive timeout!", this.player.getScoreboardName());
+                    this.disconnect(TIMEOUT_DISCONNECTION_MESSAGE, org.bukkit.event.player.PlayerKickEvent.Cause.TIMEOUT);
+                } else if (this.checkIfClosed(millis)) {
+                    this.keepAlivePending = true;
+                    this.keepAliveTime = millis; // hijack this field for 1 second intervals
+                    this.keepAlives.add(millis); // millis is ID
+                    this.send(new ClientboundKeepAlivePacket(millis));
+                }
+            }
+        } else {
+            // Gale end - Purpur - send multiple keep-alive packets
         if (!this.isSingleplayerOwner() && elapsedTime >= 15000L) { // use vanilla's 15000L between keep alive packets
             if (this.keepAlivePending) {
                 if (!this.processedDisconnect && elapsedTime >= KEEPALIVE_LIMIT) { // check keepalive limit, don't fire if already disconnected
@@ -253,6 +283,7 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
                 this.send(new ClientboundKeepAlivePacket(this.keepAliveChallenge));
             }
         }
+        } // Gale - Purpur - send multiple keep-alive packets
     }
 
     private boolean checkIfClosed(long time) {