content/browser/power_save_blocker_chromeos.cc

   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.
   4
   5 #include "content/browser/power_save_blocker_impl.h"
   6
   7 #include "base/basictypes.h"
   8 #include "base/bind.h"
   9 #include "base/memory/ref_counted.h"
  10 #include "base/memory/scoped_ptr.h"
  11 #include "chromeos/power/power_state_override.h"
  12 #include "content/public/browser/browser_thread.h"
  13
  14 namespace content {
  15
  16 class PowerSaveBlockerImpl::Delegate
  17     : public base::RefCountedThreadSafe<PowerSaveBlockerImpl::Delegate> {
  18  public:
  19   Delegate(PowerSaveBlockerType type) : type_(type) {}
  20
  21   // Creates a PowerStateOverride object to override the default power
  22   // management behavior.
  23   void ApplyBlock() {
  24     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  25     chromeos::PowerStateOverride::Mode mode =
  26         chromeos::PowerStateOverride::BLOCK_SYSTEM_SUSPEND;
  27     switch (type_) {
  28       case kPowerSaveBlockPreventAppSuspension:
  29         mode = chromeos::PowerStateOverride::BLOCK_SYSTEM_SUSPEND;
  30         break;
  31       case kPowerSaveBlockPreventDisplaySleep:
  32         mode = chromeos::PowerStateOverride::BLOCK_DISPLAY_SLEEP;
  33         break;
  34       default:
  35         NOTREACHED() << "Unhandled block type " << type_;
  36     }
  37     override_ = new chromeos::PowerStateOverride(mode);
  38   }
  39
  40   // Resets the previously-created PowerStateOverride object.
  41   void RemoveBlock() {
  42     DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
  43     override_ = NULL;
  44   }
  45
  46  private:
  47   friend class base::RefCountedThreadSafe<Delegate>;
  48   virtual ~Delegate() {}
  49
  50   PowerSaveBlockerType type_;
  51
  52   scoped_refptr<chromeos::PowerStateOverride> override_;
  53
  54   DISALLOW_COPY_AND_ASSIGN(Delegate);
  55 };
  56
  57 PowerSaveBlockerImpl::PowerSaveBlockerImpl(PowerSaveBlockerType type,
  58                                            const std::string& reason)
  59     : delegate_(new Delegate(type)) {
  60   BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
  61                           base::Bind(&Delegate::ApplyBlock, delegate_));
  62 }
  63
  64 PowerSaveBlockerImpl::~PowerSaveBlockerImpl() {
  65   BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
  66                           base::Bind(&Delegate::RemoveBlock, delegate_));
  67 }
  68
  69 }  // namespace content