1 // Copyright (c) 2012 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.
5 #include "base/ios/scoped_critical_action.h"
7 #import <UIKit/UIKit.h>
9 #include "base/logging.h"
10 #include "base/synchronization/lock.h"
15 // This implementation calls |beginBackgroundTaskWithExpirationHandler:| when
16 // instantiated and |endBackgroundTask:| when destroyed, creating a scope whose
17 // execution will continue (temporarily) even after the app is backgrounded.
18 ScopedCriticalAction::ScopedCriticalAction() {
19 background_task_id_ = [[UIApplication sharedApplication]
20 beginBackgroundTaskWithExpirationHandler:^{
21 DLOG(WARNING) << "Background task with id " << background_task_id_
23 // Note if |endBackgroundTask:| is not called for each task before time
24 // expires, the system kills the application.
27 if (background_task_id_ == UIBackgroundTaskInvalid) {
29 "beginBackgroundTaskWithExpirationHandler: returned an invalid ID";
31 VLOG(3) << "Beginning background task with id " << background_task_id_;
35 ScopedCriticalAction::~ScopedCriticalAction() {
39 void ScopedCriticalAction::EndBackgroundTask() {
40 UIBackgroundTaskIdentifier task_id;
42 AutoLock lock_scope(background_task_id_lock_);
43 if (background_task_id_ == UIBackgroundTaskInvalid)
45 task_id = background_task_id_;
46 background_task_id_ = UIBackgroundTaskInvalid;
49 VLOG(3) << "Ending background task with id " << task_id;
50 [[UIApplication sharedApplication] endBackgroundTask:task_id];