Gale/patches/server/0091-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

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

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SOFTWARE.

diff --git a/src/main/java/net/minecraft/server/network/ServerCommonPacketListenerImpl.java b/src/main/java/net/minecraft/server/network/ServerCommonPacketListenerImpl.java
index d777e5914148103dbdbfef7c8e4f8e012fa58b6d..92815589da3c2a1cb768ac8081660c9c2ccb2b14 100644
--- a/src/main/java/net/minecraft/server/network/ServerCommonPacketListenerImpl.java
+++ b/src/main/java/net/minecraft/server/network/ServerCommonPacketListenerImpl.java
@@ -79,10 +79,14 @@ 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;
     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 ResourceLocation MINECRAFT_BRAND = ResourceLocation.withDefaultNamespace("brand"); // Paper - Brand support
 
     public ServerCommonPacketListenerImpl(MinecraftServer minecraftserver, Connection networkmanager, CommonListenerCookie commonlistenercookie, ServerPlayer player) { // CraftBukkit
@@ -136,6 +140,16 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
     @Override
     public void handleKeepAlive(ServerboundKeepAlivePacket packet) {
         //PacketUtils.ensureRunningOnSameThread(packet, this, this.player.serverLevel()); // CraftBukkit // Paper - handle ServerboundKeepAlivePacket async
+        // 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);
 
@@ -144,6 +158,7 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
         } else if (!this.isSingleplayerOwner()) {
             this.disconnectAsync(ServerCommonPacketListenerImpl.TIMEOUT_DISCONNECTION_MESSAGE, PlayerKickEvent.Cause.TIMEOUT); // Paper - add proper async disconnect
         }
+        } // Gale - Purpur - send multiple keep-alive packets
 
     }
 
@@ -259,6 +274,21 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
         long currentTime = Util.getMillis();
         long elapsedTime = currentTime - 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(ServerCommonPacketListenerImpl.TIMEOUT_DISCONNECTION_MESSAGE, org.bukkit.event.player.PlayerKickEvent.Cause.TIMEOUT);
+                } else if (this.checkIfClosed(currentTime)) {
+                    this.keepAlivePending = true;
+                    this.keepAliveTime = currentTime; // hijack this field for 1 second intervals
+                    this.keepAlives.add(currentTime); // currentTime is ID
+                    this.send(new ClientboundKeepAlivePacket(currentTime));
+                }
+            }
+        } else {
+            // Gale end - Purpur - send multiple keep-alive packets
         if (!this.isSingleplayerOwner() && elapsedTime >= 15000L) { // Paper - use vanilla's 15000L between keep alive packets
             if (this.keepAlivePending && !this.processedDisconnect && elapsedTime >= KEEPALIVE_LIMIT) { // Paper - check keepalive limit, don't fire if already disconnected
                 this.disconnect(ServerCommonPacketListenerImpl.TIMEOUT_DISCONNECTION_MESSAGE, PlayerKickEvent.Cause.TIMEOUT); // Paper - kick event cause
@@ -269,6 +299,7 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
                 this.send(new ClientboundKeepAlivePacket(this.keepAliveChallenge));
             }
         }
+        } // Gale - Purpur - send multiple keep-alive packets
         // Paper end - give clients a longer time to respond to pings as per pre 1.12.2 timings
     }
 
diff --git a/src/main/java/org/galemc/gale/configuration/GaleGlobalConfiguration.java b/src/main/java/org/galemc/gale/configuration/GaleGlobalConfiguration.java
index b0da100cf972d4e39b130c99550ebcc763f055ee..b2ee56fa4be361e9151389787313594493dd7a2e 100644
--- a/src/main/java/org/galemc/gale/configuration/GaleGlobalConfiguration.java
+++ b/src/main/java/org/galemc/gale/configuration/GaleGlobalConfiguration.java
@@ -52,6 +52,12 @@ public class GaleGlobalConfiguration extends ConfigurationPart {
     public class Misc extends ConfigurationPart {
 
         public boolean verifyChatOrder = true; // Gale - Pufferfish - make chat order verification configurable
+
+        public Keepalive keepalive;
+        public class Keepalive extends ConfigurationPart {
+            public boolean sendMultiple = true; // Gale - Purpur - send multiple keep-alive packets
+        }
+
     }
 
     public LogToConsole logToConsole;