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
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.

diff --git a/net/minecraft/server/network/ServerCommonPacketListenerImpl.java b/net/minecraft/server/network/ServerCommonPacketListenerImpl.java
index 29f19fef7fdefa345b862cd2d5776c2655085c1f..3d14ca26938d8b74a456ab4b27849a992bbf8b74 100644
--- a/net/minecraft/server/network/ServerCommonPacketListenerImpl.java
+++ b/net/minecraft/server/network/ServerCommonPacketListenerImpl.java
@@ -38,10 +38,11 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
     public final Connection connection; // Paper
     private final boolean transferred;
     //private long keepAliveTime; // Paper - improve keepalives
-    //private boolean keepAlivePending; // Paper - improve keepalives
+    private boolean keepAlivePending; // Paper - improve keepalives // Purpur - Alternative Keepalive Handling
     //private long keepAliveChallenge; // Paper - improve keepalives
     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 volatile int latency; // Paper - improve keepalives - make volatile
     private final io.papermc.paper.util.KeepAlive keepAlive; // Paper - improve keepalives
     private volatile boolean suspendFlushingOnServerThread = false;
@@ -50,7 +51,10 @@ 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
     // Paper start - retain certain values
     public @Nullable String playerBrand;
@@ -97,6 +101,18 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
         // Paper start - improve keepalives
         long now = System.nanoTime();
         io.papermc.paper.util.KeepAlive.PendingKeepAlive pending = this.keepAlive.pendingKeepAlives.peek();
+        // 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());
+                int updatedLatency = (this.latency * 3 + ping) / 4;
+                this.latency = updatedLatency;
+                this.keepAlivePending = false;
+                this.keepAlives.clear(); // We got a valid response, let's roll with it and forget the rest
+            }
+            return;
+        } else {
+            // Gale end - Purpur - send multiple keep-alive packets
         if (pending != null && pending.challengeId() == packet.getId()) {
             this.keepAlive.pendingKeepAlives.remove(pending);
 
@@ -108,6 +124,7 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
             this.latency = this.keepAlive.pingCalculator5s.getAvgLatencyMS();
             return;
         }
+        } // Gale - Purpur - send multiple keep-alive packets
 
         for (java.util.Iterator<io.papermc.paper.util.KeepAlive.PendingKeepAlive> itr = this.keepAlive.pendingKeepAlives.iterator(); itr.hasNext();) {
             io.papermc.paper.util.KeepAlive.PendingKeepAlive ka = itr.next();
@@ -249,6 +266,23 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
     protected void keepConnectionAlive() {
         long millis = Util.getMillis();
         // Paper start - improve keepalives
+        // Gale start - Purpur - send multiple keep-alive packets
+        if (org.galemc.gale.configuration.GaleGlobalConfiguration.get().misc.keepalive.sendMultiple) {
+            if (this.checkIfClosed(millis) && !this.processedDisconnect) {
+                long currTime = System.nanoTime();
+                if ((currTime - this.keepAlive.lastKeepAliveTx) >= java.util.concurrent.TimeUnit.SECONDS.toNanos(1L)) { // 1 second
+                    this.keepAlive.lastKeepAliveTx = currTime;
+                    if (this.keepAlivePending && !this.processedDisconnect && keepAlives.size() * 1000L >= KEEPALIVE_LIMIT) {
+                        this.disconnect(TIMEOUT_DISCONNECTION_MESSAGE, io.papermc.paper.connection.DisconnectionReason.TIMEOUT);
+                    } else if (this.checkIfClosed(millis)) {
+                        this.keepAlivePending = true;
+                        this.keepAlives.add(millis); // currentTime is ID
+                        this.send(new ClientboundKeepAlivePacket(millis));
+                    }
+                }
+            }
+        } else {
+            // Gale end - Purpur - send multiple keep-alive packets
         if (this.checkIfClosed(millis) && !this.processedDisconnect) {
             long currTime = System.nanoTime();
 
@@ -267,6 +301,7 @@ public abstract class ServerCommonPacketListenerImpl implements ServerCommonPack
                 // Paper end - improve keepalives
             }
         }
+        } // Gale - Purpur - send multiple keep-alive packets
     }
 
     private boolean checkIfClosed(long time) {