From 7704d894965b87c162efdce37dbcb5939579a91f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?kleines=20Filmr=C3=B6llchen?= <filmroellchen@serenityos.org>
Date: Thu, 11 May 2023 21:58:40 +0200
Subject: [PATCH] LibCore: Cancel jobs on event loop exit

This important feature was regressed with the recent architectural
change.
---
 Userland/Libraries/LibCore/EventLoop.cpp        |  1 +
 Userland/Libraries/LibCore/ThreadEventQueue.cpp | 10 ++++++++++
 Userland/Libraries/LibCore/ThreadEventQueue.h   |  1 +
 3 files changed, 12 insertions(+)

diff --git a/Userland/Libraries/LibCore/EventLoop.cpp b/Userland/Libraries/LibCore/EventLoop.cpp
index e20e9730ef..2d1a0a657d 100644
--- a/Userland/Libraries/LibCore/EventLoop.cpp
+++ b/Userland/Libraries/LibCore/EventLoop.cpp
@@ -48,6 +48,7 @@ EventLoop& EventLoop::current()
 
 void EventLoop::quit(int code)
 {
+    ThreadEventQueue::current().cancel_all_pending_jobs();
     m_impl->quit(code);
 }
 
diff --git a/Userland/Libraries/LibCore/ThreadEventQueue.cpp b/Userland/Libraries/LibCore/ThreadEventQueue.cpp
index 13e1811800..61a947e653 100644
--- a/Userland/Libraries/LibCore/ThreadEventQueue.cpp
+++ b/Userland/Libraries/LibCore/ThreadEventQueue.cpp
@@ -11,6 +11,7 @@
 #include <LibCore/Promise.h>
 #include <LibCore/ThreadEventQueue.h>
 #include <LibThreading/Mutex.h>
+#include <errno.h>
 
 namespace Core {
 
@@ -76,6 +77,15 @@ void ThreadEventQueue::add_job(NonnullRefPtr<Promise<NonnullRefPtr<Object>>> pro
     m_private->pending_promises.append(move(promise));
 }
 
+void ThreadEventQueue::cancel_all_pending_jobs()
+{
+    Threading::MutexLocker lock(m_private->mutex);
+    for (auto const& promise : m_private->pending_promises)
+        promise->cancel(Error::from_errno(ECANCELED));
+
+    m_private->pending_promises.clear();
+}
+
 size_t ThreadEventQueue::process()
 {
     decltype(m_private->queued_events) events;
diff --git a/Userland/Libraries/LibCore/ThreadEventQueue.h b/Userland/Libraries/LibCore/ThreadEventQueue.h
index 675e7b8e76..76af48da22 100644
--- a/Userland/Libraries/LibCore/ThreadEventQueue.h
+++ b/Userland/Libraries/LibCore/ThreadEventQueue.h
@@ -29,6 +29,7 @@ public:
 
     // Used by Threading::BackgroundAction.
     void add_job(NonnullRefPtr<Promise<NonnullRefPtr<Object>>>);
+    void cancel_all_pending_jobs();
 
     // Returns true if there are events waiting to be flushed.
     bool has_pending_events() const;