summaryrefslogtreecommitdiff
path: root/Userland/Libraries/LibCore/EventLoop.h
blob: ecdc104c6341801bf78512a1bd9d4973dbd9235c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
/*
 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
 * Copyright (c) 2022, kleines Filmröllchen <malu.bertsch@gmail.com>
 * Copyright (c) 2022, the SerenityOS developers.
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#pragma once

#include <AK/Forward.h>
#include <AK/Function.h>
#include <AK/HashMap.h>
#include <AK/Noncopyable.h>
#include <AK/NonnullOwnPtr.h>
#include <AK/NonnullRefPtr.h>
#include <AK/Time.h>
#include <AK/Vector.h>
#include <AK/WeakPtr.h>
#include <LibCore/DeferredInvocationContext.h>
#include <LibCore/Event.h>
#include <LibCore/Forward.h>
#include <LibThreading/MutexProtected.h>
#include <sys/time.h>
#include <sys/types.h>

namespace Core {

class EventLoop {
public:
    enum class MakeInspectable {
        No,
        Yes,
    };

    enum class ShouldWake {
        No,
        Yes
    };

    explicit EventLoop(MakeInspectable = MakeInspectable::No);
    ~EventLoop();
    static void initialize_wake_pipes();

    int exec();

    enum class WaitMode {
        WaitForEvents,
        PollForEvents,
    };

    // process events, generally called by exec() in a loop.
    // this should really only be used for integrating with other event loops
    size_t pump(WaitMode = WaitMode::WaitForEvents);

    void spin_until(Function<bool()>);

    void post_event(Object& receiver, NonnullOwnPtr<Event>&&, ShouldWake = ShouldWake::No);
    void wake_once(Object& receiver, int custom_event_type);

    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.extend(move(other.m_queued_events));
    }

    static void wake_current();
    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);

    static bool has_been_instantiated();

    void deferred_invoke(Function<void()> invokee)
    {
        auto context = DeferredInvocationContext::construct();
        post_event(context, make<Core::DeferredInvocationEvent>(context, move(invokee)));
    }

private:
    void wait_for_event(WaitMode);
    Optional<Time> 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() = default;

        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 thread_local int s_wake_pipe_fds[2];
    static thread_local bool s_wake_pipe_initialized;

    // The wake pipe of this event loop needs to be accessible from other threads.
    int (*m_wake_pipe_fds)[2];

    struct Private;
    NonnullOwnPtr<Private> m_private;
};

inline void deferred_invoke(Function<void()> invokee)
{
    EventLoop::current().deferred_invoke(move(invokee));
}

}