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 #ifndef CHROME_BROWSER_CHROMEOS_POWER_RENDERER_FREEZER_H_ 6 #define CHROME_BROWSER_CHROMEOS_POWER_RENDERER_FREEZER_H_ 7 8 #include "base/callback.h" 9 #include "base/cancelable_callback.h" 10 #include "base/macros.h" 11 #include "base/memory/scoped_ptr.h" 12 #include "base/memory/weak_ptr.h" 13 #include "base/time/time.h" 14 #include "chromeos/chromeos_export.h" 15 #include "chromeos/dbus/power_manager_client.h" 16 17 namespace chromeos { 18 19 // Freezes the chrome renderers when the system is about to suspend and thaws 20 // them after the system fully resumes. This class registers itself as a 21 // PowerManagerClient::Observer on creation and unregisters itself on 22 // destruction. 23 class CHROMEOS_EXPORT RendererFreezer : public PowerManagerClient::Observer { 24 public: 25 class Delegate { 26 public: ~Delegate()27 virtual ~Delegate() {} 28 29 // Freezes the chrome renderers. Returns true if the operation was 30 // successful. 31 virtual bool FreezeRenderers() = 0; 32 33 // Thaws the chrome renderers. Returns true if the operation was 34 // successful. 35 virtual bool ThawRenderers() = 0; 36 37 // Returns true iff the delegate is capable of freezing renderers. 38 virtual bool CanFreezeRenderers() = 0; 39 }; 40 41 explicit RendererFreezer(scoped_ptr<Delegate> delegate); 42 virtual ~RendererFreezer(); 43 44 // PowerManagerClient::Observer implementation 45 virtual void SuspendImminent() OVERRIDE; 46 virtual void SuspendDone(const base::TimeDelta& sleep_duration) OVERRIDE; 47 48 private: 49 // Called when all asynchronous work is complete and renderers can be frozen. 50 void OnReadyToSuspend(const base::Closure& power_manager_callback); 51 52 // Used to ensure that renderers do not get frozen if the suspend is canceled. 53 base::CancelableClosure suspend_readiness_callback_; 54 55 bool frozen_; 56 57 scoped_ptr<Delegate> delegate_; 58 59 base::WeakPtrFactory<RendererFreezer> weak_factory_; 60 61 DISALLOW_COPY_AND_ASSIGN(RendererFreezer); 62 }; 63 64 } // namespace chromeos 65 66 #endif // CHROME_BROWSER_CHROMEOS_POWER_RENDERER_FREEZER_H_ 67