papermc/Spigot-Server-Patches/0393-ChunkMapDistance-CME.patch

From 5c4cd1ff04671b21a3b9b30091e5dcb9306decfa Mon Sep 17 00:00:00 2001
From: Shane Freeder <theboyetronic@gmail.com>
Date: Wed, 29 May 2019 04:01:22 +0100
Subject: [PATCH] ChunkMapDistance CME


diff --git a/src/main/java/net/minecraft/server/ChunkMapDistance.java b/src/main/java/net/minecraft/server/ChunkMapDistance.java
index a116ee128..8572eeba1 100644
--- a/src/main/java/net/minecraft/server/ChunkMapDistance.java
+++ b/src/main/java/net/minecraft/server/ChunkMapDistance.java
@@ -36,7 +36,7 @@ public abstract class ChunkMapDistance {
     private final ChunkMapDistance.a e = new ChunkMapDistance.a();
     private final ChunkMapDistance.b f = new ChunkMapDistance.b(8);
     private final ChunkMapDistance.c g = new ChunkMapDistance.c(33);
-    private final Set<PlayerChunk> h = Sets.newHashSet(); // PAIL pendingChunkUpdates
+    private final java.util.Queue<PlayerChunk> h = new java.util.LinkedList<>(); // PAIL pendingChunkUpdates // Paper - use a queue
     private final PlayerChunk.c i;
     private final Mailbox<ChunkTaskQueueSorter.a<Runnable>> j;
     private final Mailbox<ChunkTaskQueueSorter.b> k;
@@ -98,26 +98,12 @@ public abstract class ChunkMapDistance {
             ;
         }
 
+        // Paper start
         if (!this.h.isEmpty()) {
-            // CraftBukkit start
-            // Iterate pending chunk updates with protection against concurrent modification exceptions
-            java.util.Iterator<PlayerChunk> iter = this.h.iterator();
-            int expectedSize = this.h.size();
-            do {
-                PlayerChunk playerchunk = iter.next();
-                iter.remove();
-                expectedSize--;
-
-                playerchunk.a(playerchunkmap);
-
-                // Reset iterator if set was modified using add()
-                if (this.h.size() != expectedSize) {
-                    expectedSize = this.h.size();
-                    iter = this.h.iterator();
-                }
-            } while (iter.hasNext());
-            // CraftBukkit end
-
+            while(!this.h.isEmpty()) {
+                this.h.remove().a(playerchunkmap);
+            }
+            // Paper end
             return true;
         } else {
             if (!this.l.isEmpty()) {
-- 
2.22.0