blob: 53e5418078e442e01b16f9c620634e56b413b19f (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
|
// Copyright (c) 2012 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.
#ifndef CONTENT_BROWSER_POWER_SAVE_BLOCKER_H_
#define CONTENT_BROWSER_POWER_SAVE_BLOCKER_H_
#include <string>
#include <vector>
#include "base/basictypes.h"
#include "base/memory/ref_counted.h"
#include "content/common/content_export.h"
namespace content {
// A RAII-style class to block the system from entering low-power (sleep) mode.
// This class is thread-safe; it may be constructed and deleted on any thread.
class CONTENT_EXPORT PowerSaveBlocker {
public:
enum PowerSaveBlockerType {
// Prevent the application from being suspended. On some platforms, apps may
// be suspended when they are not visible to the user. This type of block
// requests that the app continue to run in that case, and on all platforms
// prevents the system from sleeping.
// Example use cases: downloading a file, playing audio.
kPowerSaveBlockPreventAppSuspension,
// Prevent the display from going to sleep. This also has the side effect of
// preventing the system from sleeping, but does not necessarily prevent the
// app from being suspended on some platforms if the user hides it.
// Example use case: playing video.
kPowerSaveBlockPreventDisplaySleep,
};
// Pass in the type of power save blocking desired. If multiple types of
// blocking are desired, instantiate one PowerSaveBlocker for each type.
// |reason| may be provided to the underlying system APIs on some platforms.
PowerSaveBlocker(PowerSaveBlockerType type, const std::string& reason);
~PowerSaveBlocker();
private:
class Delegate;
// Implementations of this class may need a second object with different
// lifetime than the RAII container, or additional storage. This member is
// here for that purpose. If not used, just define the class as an empty
// RefCounted (or RefCountedThreadSafe) like so to make it compile:
// class PowerSaveBlocker::Delegate
// : public base::RefCounted<PowerSaveBlocker::Delegate> {
// private:
// friend class base::RefCounted<Delegate>;
// ~Delegate() {}
// };
scoped_refptr<Delegate> delegate_;
DISALLOW_COPY_AND_ASSIGN(PowerSaveBlocker);
};
} // namespace content
#endif // CONTENT_BROWSER_POWER_SAVE_BLOCKER_H_
|