ladybird/Libraries/LibCore/EventLoop.h
Tom 21e6f5176c LibCore: Harden signal handling code to be called in global destrcutors
Move some more complex globals into a Singleton, which allows it being
used from global destructors. It solves problems where some global
variables, such as HashMaps may already be deleted, triggering crashes
trying to use them.
2021-01-09 21:12:31 +01:00

122 lines
3.7 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <AK/Forward.h>
#include <AK/Function.h>
#include <AK/HashMap.h>
#include <AK/Noncopyable.h>
#include <AK/NonnullOwnPtr.h>
#include <AK/Vector.h>
#include <AK/WeakPtr.h>
#include <LibCore/Forward.h>
#include <sys/time.h>
#include <sys/types.h>
namespace Core {
class EventLoop {
public:
EventLoop();
~EventLoop();
int exec();
enum class WaitMode {
WaitForEvents,
PollForEvents,
};
// processe events, generally called by exec() in a loop.
// this should really only be used for integrating with other event loops
void pump(WaitMode = WaitMode::WaitForEvents);
void post_event(Object& receiver, NonnullOwnPtr<Event>&&);
static EventLoop& main();
static EventLoop& current();
bool was_exit_requested() const { return m_exit_requested; }
static int register_timer(Object&, int milliseconds, bool should_reload, TimerShouldFireWhenNotVisible);
static bool unregister_timer(int timer_id);
static void register_notifier(Badge<Notifier>, Notifier&);
static void unregister_notifier(Badge<Notifier>, Notifier&);
void quit(int);
void unquit();
void take_pending_events_from(EventLoop& other)
{
m_queued_events.append(move(other.m_queued_events));
}
static void wake();
static int register_signal(int signo, Function<void(int)> handler);
static void unregister_signal(int handler_id);
// Note: Boost uses Parent/Child/Prepare, but we don't really have anything
// interesting to do in the parent or before forking.
enum class ForkEvent {
Child,
};
static void notify_forked(ForkEvent);
private:
bool start_rpc_server();
void wait_for_event(WaitMode);
Optional<struct timeval> get_next_timer_expiration();
static void dispatch_signal(int);
static void handle_signal(int);
struct QueuedEvent {
AK_MAKE_NONCOPYABLE(QueuedEvent);
public:
QueuedEvent(Object& receiver, NonnullOwnPtr<Event>);
QueuedEvent(QueuedEvent&&);
~QueuedEvent();
WeakPtr<Object> receiver;
NonnullOwnPtr<Event> event;
};
Vector<QueuedEvent, 64> m_queued_events;
static pid_t s_pid;
bool m_exit_requested { false };
int m_exit_code { 0 };
static int s_wake_pipe_fds[2];
struct Private;
NonnullOwnPtr<Private> m_private;
};
}