From ac70a0a7fb0a201f7933566c464af22a734db430 Mon Sep 17 00:00:00 2001
From: MhaWay <Manu573@live.it>
Date: Tue, 7 Apr 2026 11:06:52 +0200
Subject: [PATCH] Abort join point creation when host disconnects

---
 Source/Common/PlayerManager.cs |  6 ++++++
 Source/Common/WorldData.cs     | 11 +++++++++++
 Source/Tests/ServerTest.cs     | 25 +++++++++++++++++++++++++
 3 files changed, 42 insertions(+)

diff --git a/Source/Common/PlayerManager.cs b/Source/Common/PlayerManager.cs
index ab394fd79..cc3da9284 100644
--- a/Source/Common/PlayerManager.cs
+++ b/Source/Common/PlayerManager.cs
@@ -71,6 +71,12 @@ public void SetDisconnected(ConnectionBase conn, MpDisconnectReason reason)
             ServerPlayer player = conn.serverPlayer;
             Players.Remove(player);
 
+            if (player.IsHost && server.worldData.CreatingJoinPoint)
+            {
+                server.worldData.AbortJoinPointCreation();
+                ServerLog.Log("Aborted join point creation because the host disconnected.");
+            }
+
             if (player.hasJoined)
             {
                 // Send PlayerCount command to remove the player from their last known map
diff --git a/Source/Common/WorldData.cs b/Source/Common/WorldData.cs
index 06d88f071..a76e18dfb 100644
--- a/Source/Common/WorldData.cs
+++ b/Source/Common/WorldData.cs
@@ -52,6 +52,17 @@ public void EndJoinPointCreation()
         tmpMapCmds = null;
         lastJoinPointAtWorkTicks = Server.workTicks;
         dataSource!.SetResult(this);
+        dataSource = null;
+    }
+
+    public void AbortJoinPointCreation()
+    {
+        if (!CreatingJoinPoint)
+            return;
+
+        tmpMapCmds = null;
+        dataSource?.SetResult(this);
+        dataSource = null;
     }
 
     public Task<WorldData> WaitJoinPoint()
diff --git a/Source/Tests/ServerTest.cs b/Source/Tests/ServerTest.cs
index b8fbab894..a84508590 100644
--- a/Source/Tests/ServerTest.cs
+++ b/Source/Tests/ServerTest.cs
@@ -45,6 +45,31 @@ public void Test()
         }
     }
 
+    [Test]
+    public async Task JoinPointAbortUnblocksWaiters()
+    {
+        var server = new MultiplayerServer(new ServerSettings
+        {
+            gameName = "Test",
+            direct = false,
+            lan = false
+        });
+
+        Assert.That(server.worldData.TryStartJoinPointCreation(true), Is.True);
+        Assert.That(server.worldData.CreatingJoinPoint, Is.True);
+
+        var waitTask = server.worldData.WaitJoinPoint();
+        Assert.That(waitTask.IsCompleted, Is.False);
+
+        server.worldData.AbortJoinPointCreation();
+
+        var completed = await waitTask.WaitAsync(TimeSpan.FromSeconds(1));
+
+        Assert.That(completed, Is.SameAs(server.worldData));
+        Assert.That(server.worldData.CreatingJoinPoint, Is.False);
+        Assert.That(server.worldData.WaitJoinPoint().IsCompleted, Is.True);
+    }
+
     private void ConnectClient(int port)
     {
         var clientListener = new TestNetListener();