content/renderer/device_sensors/device_light_event_pump.h

   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 CONTENT_RENDERER_DEVICE_SENSORS_DEVICE_LIGHT_EVENT_PUMP_H_
   6 #define CONTENT_RENDERER_DEVICE_SENSORS_DEVICE_LIGHT_EVENT_PUMP_H_
   7
   8 #include "base/memory/scoped_ptr.h"
   9 #include "content/common/device_sensors/device_light_data.h"
  10 #include "content/renderer/device_sensors/device_sensor_event_pump.h"
  11 #include "content/renderer/shared_memory_seqlock_reader.h"
  12
  13 namespace blink {
  14 class WebDeviceLightListener;
  15 }
  16
  17 namespace content {
  18
  19 typedef SharedMemorySeqLockReader<DeviceLightData>
  20     DeviceLightSharedMemoryReader;
  21
  22 class CONTENT_EXPORT DeviceLightEventPump
  23     : public DeviceSensorEventPump<blink::WebDeviceLightListener> {
  24  public:
  25   explicit DeviceLightEventPump(RenderThread* thread);
  26   ~DeviceLightEventPump() override;
  27
  28   // Sets the listener to receive updates for device light data at
  29   // regular intervals. Returns true if the registration was successful.
  30   bool SetListener(blink::WebDeviceLightListener* listener);
  31
  32   // PlatformEventObserver implementation.
  33   bool OnControlMessageReceived(const IPC::Message& message) override;
  34   void SendFakeDataForTesting(void* data) override;
  35
  36  protected:
  37   // Methods overriden from base class DeviceSensorEventPump
  38   void FireEvent() override;
  39   bool InitializeReader(base::SharedMemoryHandle handle) override;
  40
  41   // PlatformEventObserver implementation.
  42   void SendStartMessage() override;
  43   void SendStopMessage() override;
  44
  45  private:
  46   bool ShouldFireEvent(double data) const;
  47
  48   scoped_ptr<DeviceLightSharedMemoryReader> reader_;
  49   double last_seen_data_;
  50
  51   DISALLOW_COPY_AND_ASSIGN(DeviceLightEventPump);
  52 };
  53
  54 }  // namespace content
  55
  56 #endif  // CONTENT_RENDERER_DEVICE_SENSORS_DEVICE_LIGHT_EVENT_PUMP_H_