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Serenity Operating System
1/*
2 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright notice, this
9 * list of conditions and the following disclaimer.
10 *
11 * 2. Redistributions in binary form must reproduce the above copyright notice,
12 * this list of conditions and the following disclaimer in the documentation
13 * and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
16 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
18 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
21 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
22 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
23 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
24 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27#pragma once
28
29#include <AK/Function.h>
30#include <AK/NonnullOwnPtr.h>
31#include <AK/OwnPtr.h>
32#include <AK/SinglyLinkedList.h>
33#include <Kernel/Devices/PIT.h>
34
35namespace Kernel {
36
37struct Timer {
38 u64 id;
39 u64 expires;
40 Function<void()> callback;
41 bool operator<(const Timer& rhs) const
42 {
43 return expires < rhs.expires;
44 }
45 bool operator>(const Timer& rhs) const
46 {
47 return expires > rhs.expires;
48 }
49 bool operator==(const Timer& rhs) const
50 {
51 return id == rhs.id;
52 }
53};
54
55enum TimeUnit {
56 MS = TICKS_PER_SECOND / 1000,
57 S = TICKS_PER_SECOND,
58 M = TICKS_PER_SECOND * 60
59};
60
61class TimerQueue {
62public:
63 static TimerQueue& the();
64
65 u64 add_timer(NonnullOwnPtr<Timer>&&);
66 u64 add_timer(u64 duration, TimeUnit, Function<void()>&& callback);
67 bool cancel_timer(u64 id);
68 void fire();
69
70private:
71 void update_next_timer_due();
72
73 u64 m_next_timer_due { 0 };
74 u64 m_timer_id_count { 0 };
75 SinglyLinkedList<NonnullOwnPtr<Timer>> m_timer_queue;
76};
77
78}