LibCore: Move post_event() back to EventLoopImplementation

This shouldn't have been moved to EventLoopManager, as the manager is
global and one-per-process, and the implementation is one-per-loop.

This makes cross-thread event posting work again, and unbreaks
SoundPlayer (and probably other things as well.)

Ladybird/EventLoopImplementationQt.cpp

@@ -74,12 +74,11 @@ void EventLoopImplementationQt::wake()
         m_event_loop.wakeUp();
 }
 
-void EventLoopManagerQt::deferred_invoke(Function<void()> function)
+void EventLoopImplementationQt::post_event(Core::Object& receiver, NonnullOwnPtr<Core::Event>&& event)
 {
-    VERIFY(function);
+    m_thread_event_queue.post_event(receiver, move(event));
-    QTimer::singleShot(0, [function = move(function)] {
+    if (&m_thread_event_queue != &Core::ThreadEventQueue::current())
-        function();
+        wake();
-    });
 }
 
 static void qt_timer_fired(int timer_id, Core::TimerShouldFireWhenNotVisible should_fire_when_not_visible, Core::Object& object)

Ladybird/EventLoopImplementationQt.h

@@ -22,8 +22,6 @@ public:
     virtual ~EventLoopManagerQt() override;
     virtual NonnullOwnPtr<Core::EventLoopImplementation> make_implementation() override;
 
-    virtual void deferred_invoke(Function<void()>) override;
-
     virtual int register_timer(Core::Object&, int milliseconds, bool should_reload, Core::TimerShouldFireWhenNotVisible) override;
     virtual bool unregister_timer(int timer_id) override;
 
@@ -52,6 +50,7 @@ public:
     virtual size_t pump(PumpMode) override;
     virtual void quit(int) override;
     virtual void wake() override;
+    virtual void post_event(Core::Object& receiver, NonnullOwnPtr<Core::Event>&&) override;
 
     // FIXME: These APIs only exist for obscure use-cases inside SerenityOS. Try to get rid of them.
     virtual void unquit() override { }

Userland/Libraries/LibCore/EventLoop.cpp

@@ -88,7 +88,7 @@ size_t EventLoop::pump(WaitMode mode)
 
 void EventLoop::post_event(Object& receiver, NonnullOwnPtr<Event>&& event)
 {
-    EventLoopManager::the().post_event(receiver, move(event));
+    m_impl->post_event(receiver, move(event));
 }
 
 void EventLoop::add_job(NonnullRefPtr<Promise<NonnullRefPtr<Object>>> job_promise)

Userland/Libraries/LibCore/EventLoopImplementation.cpp

@@ -12,7 +12,10 @@
 
 namespace Core {
 
-EventLoopImplementation::EventLoopImplementation() = default;
+EventLoopImplementation::EventLoopImplementation()
+    : m_thread_event_queue(ThreadEventQueue::current())
+{
+}
 
 EventLoopImplementation::~EventLoopImplementation() = default;
 
@@ -29,20 +32,8 @@ void EventLoopManager::install(Core::EventLoopManager& manager)
     s_event_loop_manager = &manager;
 }
 
-EventLoopManager::EventLoopManager()
+EventLoopManager::EventLoopManager() = default;
-    : m_thread_event_queue(ThreadEventQueue::current())
-{
-}
 
 EventLoopManager::~EventLoopManager() = default;
 
-void EventLoopManager::post_event(Object& receiver, NonnullOwnPtr<Event>&& event)
-{
-    m_thread_event_queue.post_event(receiver, move(event));
-
-    // Wake up this EventLoopImplementation if this is a cross-thread event posting.
-    if (&ThreadEventQueue::current() != &m_thread_event_queue)
-        wake();
-}
-
 }

Userland/Libraries/LibCore/EventLoopImplementation.h

@@ -29,11 +29,8 @@ public:
     virtual void register_notifier(Notifier&) = 0;
     virtual void unregister_notifier(Notifier&) = 0;
 
-    void post_event(Object& receiver, NonnullOwnPtr<Event>&&);
     virtual void did_post_event() = 0;
 
-    virtual void deferred_invoke(Function<void()>) = 0;
-
     // FIXME: These APIs only exist for obscure use-cases inside SerenityOS. Try to get rid of them.
     virtual int register_signal(int signal_number, Function<void(int)> handler) = 0;
     virtual void unregister_signal(int handler_id) = 0;
@@ -42,7 +39,6 @@ public:
 
 protected:
     EventLoopManager();
-    ThreadEventQueue& m_thread_event_queue;
 };
 
 class EventLoopImplementation {
@@ -59,6 +55,8 @@ public:
     virtual void quit(int) = 0;
     virtual void wake() = 0;
 
+    virtual void post_event(Object& receiver, NonnullOwnPtr<Event>&&) = 0;
+
     // FIXME: These APIs only exist for obscure use-cases inside SerenityOS. Try to get rid of them.
     virtual void unquit() = 0;
     virtual bool was_exit_requested() const = 0;
@@ -66,6 +64,7 @@ public:
 
 protected:
     EventLoopImplementation();
+    ThreadEventQueue& m_thread_event_queue;
 };
 
 }

Userland/Libraries/LibCore/EventLoopImplementationUnix.cpp

@@ -126,6 +126,13 @@ bool EventLoopImplementationUnix::was_exit_requested() const
     return m_exit_requested;
 }
 
+void EventLoopImplementationUnix::post_event(Object& receiver, NonnullOwnPtr<Event>&& event)
+{
+    m_thread_event_queue.post_event(receiver, move(event));
+    if (&m_thread_event_queue != &ThreadEventQueue::current())
+        wake();
+}
+
 void EventLoopImplementationUnix::wake()
 {
     int wake_event = 0;
@@ -138,13 +145,6 @@ void EventLoopManagerUnix::wake()
     MUST(Core::System::write(ThreadData::the().wake_pipe_fds[1], { &wake_event, sizeof(wake_event) }));
 }
 
-void EventLoopManagerUnix::deferred_invoke(Function<void()> invokee)
-{
-    // FIXME: Get rid of the useless DeferredInvocationContext object.
-    auto context = DeferredInvocationContext::construct();
-    post_event(context, make<DeferredInvocationEvent>(context, move(invokee)));
-}
-
 void EventLoopManagerUnix::wait_for_events(EventLoopImplementation::PumpMode mode)
 {
     auto& thread_data = ThreadData::the();

Userland/Libraries/LibCore/EventLoopImplementationUnix.h

@@ -16,8 +16,6 @@ public:
 
     virtual NonnullOwnPtr<EventLoopImplementation> make_implementation() override;
 
-    virtual void deferred_invoke(Function<void()>) override;
-
     virtual int register_timer(Object&, int milliseconds, bool should_reload, TimerShouldFireWhenNotVisible) override;
     virtual bool unregister_timer(int timer_id) override;
 
@@ -55,6 +53,7 @@ public:
     virtual void unquit() override;
     virtual bool was_exit_requested() const override;
     virtual void notify_forked_and_in_child() override;
+    virtual void post_event(Object& receiver, NonnullOwnPtr<Event>&&) override;
 
 private:
     bool m_exit_requested { false };