1 // Copyright 2012 The Chromium Authors
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "net/quic/quic_chromium_alarm_factory.h"
6
7 #include "base/check.h"
8 #include "base/functional/bind.h"
9 #include "base/location.h"
10 #include "base/memory/raw_ptr.h"
11 #include "base/task/sequenced_task_runner.h"
12 #include "base/time/tick_clock.h"
13 #include "base/time/time.h"
14 #include "base/timer/timer.h"
15 #include "net/quic/platform/impl/quic_chromium_clock.h"
16
17 namespace net {
18
19 namespace {
20
21 class QuicChromeAlarm : public quic::QuicAlarm, public base::TickClock {
22 public:
QuicChromeAlarm(const quic::QuicClock * clock,scoped_refptr<base::SequencedTaskRunner> task_runner,quic::QuicArenaScopedPtr<quic::QuicAlarm::Delegate> delegate)23 QuicChromeAlarm(const quic::QuicClock* clock,
24 scoped_refptr<base::SequencedTaskRunner> task_runner,
25 quic::QuicArenaScopedPtr<quic::QuicAlarm::Delegate> delegate)
26 : quic::QuicAlarm(std::move(delegate)),
27 clock_(clock),
28 // Unretained is safe because base::OneShotTimer never runs its task
29 // after being deleted.
30 on_alarm_callback_(base::BindRepeating(&QuicChromeAlarm::OnAlarm,
31 base::Unretained(this))),
32 timer_(std::make_unique<base::OneShotTimer>(this)) {
33 timer_->SetTaskRunner(std::move(task_runner));
34 }
35
36 protected:
SetImpl()37 void SetImpl() override {
38 DCHECK(deadline().IsInitialized());
39 const int64_t delay_us = (deadline() - clock_->Now()).ToMicroseconds();
40 timer_->Start(FROM_HERE, base::Microseconds(delay_us), on_alarm_callback_);
41 }
42
CancelImpl()43 void CancelImpl() override {
44 DCHECK(!deadline().IsInitialized());
45 timer_->Stop();
46 }
47
48 private:
OnAlarm()49 void OnAlarm() {
50 DCHECK(deadline().IsInitialized());
51
52 // In tests, the time source used by the scheduler may not be in sync with
53 // |clock_|. Because of this, the scheduler may run this task when
54 // |clock->Now()| is smaller than |deadline()|. In that case, retry later.
55 // This shouldn't happen in production.
56 if (clock_->Now() < deadline()) {
57 SetImpl();
58 return;
59 }
60
61 DCHECK_LE(deadline(), clock_->Now());
62 Fire();
63 }
64
65 // base::TickClock:
NowTicks() const66 base::TimeTicks NowTicks() const override {
67 return quic::QuicChromiumClock::QuicTimeToTimeTicks(clock_->Now());
68 }
69
70 const raw_ptr<const quic::QuicClock> clock_;
71 base::RepeatingClosure on_alarm_callback_;
72 const std::unique_ptr<base::OneShotTimer> timer_;
73 };
74
75 } // namespace
76
QuicChromiumAlarmFactory(base::SequencedTaskRunner * task_runner,const quic::QuicClock * clock)77 QuicChromiumAlarmFactory::QuicChromiumAlarmFactory(
78 base::SequencedTaskRunner* task_runner,
79 const quic::QuicClock* clock)
80 : task_runner_(task_runner), clock_(clock) {}
81
82 QuicChromiumAlarmFactory::~QuicChromiumAlarmFactory() = default;
83
CreateAlarm(quic::QuicArenaScopedPtr<quic::QuicAlarm::Delegate> delegate,quic::QuicConnectionArena * arena)84 quic::QuicArenaScopedPtr<quic::QuicAlarm> QuicChromiumAlarmFactory::CreateAlarm(
85 quic::QuicArenaScopedPtr<quic::QuicAlarm::Delegate> delegate,
86 quic::QuicConnectionArena* arena) {
87 if (arena != nullptr) {
88 return arena->New<QuicChromeAlarm>(clock_, task_runner_,
89 std::move(delegate));
90 } else {
91 return quic::QuicArenaScopedPtr<quic::QuicAlarm>(
92 new QuicChromeAlarm(clock_, task_runner_, std::move(delegate)));
93 }
94 }
95
CreateAlarm(quic::QuicAlarm::Delegate * delegate)96 quic::QuicAlarm* QuicChromiumAlarmFactory::CreateAlarm(
97 quic::QuicAlarm::Delegate* delegate) {
98 return new QuicChromeAlarm(
99 clock_, task_runner_,
100 quic::QuicArenaScopedPtr<quic::QuicAlarm::Delegate>(delegate));
101 }
102
103 } // namespace net
104