blob: 4c8d67db501c79b8683aa5bb82a2a2d19f7c5f6a [file] [log] [blame]
// Copyright 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "components/policy/core/common/policy_scheduler.h"
#include "base/threading/thread_task_runner_handle.h"
namespace policy {
PolicyScheduler::PolicyScheduler(Task task,
SchedulerCallback callback,
base::TimeDelta interval)
: task_(task), callback_(callback), interval_(interval) {
ScheduleTaskNow();
}
PolicyScheduler::~PolicyScheduler() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
}
void PolicyScheduler::ScheduleTaskNow() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
ScheduleDelayedTask(base::TimeDelta());
}
void PolicyScheduler::ScheduleDelayedTask(base::TimeDelta delay) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
if (job_) {
job_->Cancel();
}
job_ = std::make_unique<base::CancelableClosure>(base::Bind(
&PolicyScheduler::RunScheduledTask, weak_ptr_factory_.GetWeakPtr()));
base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(FROM_HERE,
job_->callback(), delay);
}
void PolicyScheduler::ScheduleNextTask() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
base::TimeDelta interval = overlap_ ? base::TimeDelta() : interval_;
const base::TimeTicks now(base::TimeTicks::Now());
// Time uses saturated arithmetics thus no under/overflow possible.
const base::TimeDelta delay = last_task_ + interval - now;
// Clamping delay to non-negative values just to be on the safe side.
ScheduleDelayedTask(std::max(base::TimeDelta(), delay));
}
void PolicyScheduler::RunScheduledTask() {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
if (task_in_progress_) {
overlap_ = true;
return;
}
overlap_ = false;
task_in_progress_ = true;
task_.Run(base::BindOnce(&PolicyScheduler::OnTaskDone,
weak_ptr_factory_.GetWeakPtr()));
}
void PolicyScheduler::OnTaskDone(bool success) {
DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
task_in_progress_ = false;
last_task_ = base::TimeTicks::Now();
callback_.Run(success);
ScheduleNextTask();
}
} // namespace policy