| OLD | NEW |
|---|
| (Empty) |
| 1 // Copyright 2014 The Chromium Authors. All rights reserved. | |
| 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 "sky/scheduler/timer.h" | |
| 6 | |
| 7 #include <cstdlib> | |
| 8 | |
| 9 #include "base/bind.h" | |
| 10 #include "base/tracked_objects.h" | |
| 11 | |
| 12 namespace sky { | |
| 13 | |
| 14 // We're willing to slop around 1/4 of a tick duration to avoid trashing our | |
| 15 // client with irregular ticks. | |
| 16 static const int64 kTickSlop = 4; | |
| 17 | |
| 18 Timer::Client::~Client() { | |
| 19 } | |
| 20 | |
| 21 Timer::Timer(Client* client, | |
| 22 scoped_refptr<base::SingleThreadTaskRunner> task_runner) | |
| 23 : client_(client), | |
| 24 task_runner_(task_runner), | |
| 25 enabled_(false), | |
| 26 weak_factory_(this) { | |
| 27 DCHECK(client_); | |
| 28 } | |
| 29 | |
| 30 Timer::~Timer() { | |
| 31 } | |
| 32 | |
| 33 void Timer::SetEnabled(bool enabled) { | |
| 34 enabled_ = enabled; | |
| 35 | |
| 36 if (enabled_ && current_target_.is_null()) | |
| 37 ScheduleNextTick(base::TimeTicks::Now()); | |
| 38 } | |
| 39 | |
| 40 void Timer::SetInterval(const TimeInterval& interval) { | |
| 41 interval_ = interval; | |
| 42 | |
| 43 // We don't have a tick scheduled, so there's no need to reschedule it. | |
| 44 if (current_target_.is_null()) | |
| 45 return; | |
| 46 | |
| 47 base::TimeTicks now = base::TimeTicks::Now(); | |
| 48 | |
| 49 base::TimeTicks new_target = NextTickTarget(now); | |
| 50 base::TimeDelta delta = base::TimeDelta::FromInternalValue( | |
| 51 std::abs((new_target - current_target_).ToInternalValue())); | |
| 52 | |
| 53 if (delta * kTickSlop < interval_.duration) | |
| 54 return; | |
| 55 | |
| 56 current_target_ = base::TimeTicks(); | |
| 57 weak_factory_.InvalidateWeakPtrs(); | |
| 58 PostTickTask(now, new_target); | |
| 59 } | |
| 60 | |
| 61 base::TimeTicks Timer::NextTickTarget(base::TimeTicks now) { | |
| 62 base::TimeTicks target = interval_.NextAfter(now); | |
| 63 | |
| 64 // If we're targeting a time that's too soon since the last tick, we push out | |
| 65 // the target to the next tick. | |
| 66 if ((target - last_tick_) * kTickSlop < interval_.duration) | |
| 67 target += interval_.duration; | |
| 68 | |
| 69 return target; | |
| 70 } | |
| 71 | |
| 72 void Timer::ScheduleNextTick(base::TimeTicks now) { | |
| 73 PostTickTask(now, NextTickTarget(now)); | |
| 74 } | |
| 75 | |
| 76 void Timer::PostTickTask(base::TimeTicks now, base::TimeTicks target) { | |
| 77 DCHECK(current_target_.is_null()); | |
| 78 current_target_ = target; | |
| 79 task_runner_->PostDelayedTask( | |
| 80 FROM_HERE, base::Bind(&Timer::OnTimerFired, weak_factory_.GetWeakPtr()), | |
| 81 current_target_ - now); | |
| 82 } | |
| 83 | |
| 84 void Timer::OnTimerFired() { | |
| 85 current_target_ = base::TimeTicks(); | |
| 86 if (!enabled_) | |
| 87 return; | |
| 88 base::TimeTicks now = base::TimeTicks::Now(); | |
| 89 ScheduleNextTick(now); | |
| 90 last_tick_ = now; | |
| 91 client_->OnTimerTick(now); | |
| 92 // We might be deleted here. | |
| 93 } | |
| 94 } | |
| OLD | NEW |
|---|
Chromium Code Reviews
