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#ifndef GEARS_GEOLOCATION_WIFI_DATA_PROVIDER_LINUX_H__
#define GEARS_GEOLOCATION_WIFI_DATA_PROVIDER_LINUX_H__

#include "gears/base/common/common.h"
#include "gears/base/common/event.h"
#include "gears/base/common/mutex.h"
#include "gears/geolocation/device_data_provider.h"
#include "gears/geolocation/thread.h"

class LinuxWifiDataProvider
    : public DeviceDataProviderBase<WifiData>,
      public Thread {
 public:
  // Allow DeviceDataProviderBase<WifiData>::Create() to access our private
  // constructor.
  friend class DeviceDataProviderBase<WifiData>;

  // DeviceDataProviderBase<WifiData> implementation.
  virtual bool GetData(WifiData *data);

 private:
  // Private constructor and destructor, callers must use
  // DeviceDataProviderBase<WifiData>::Register and
  // DeviceDataProviderBase<WifiDataa>::Unregister.
  LinuxWifiDataProvider();
  virtual ~LinuxWifiDataProvider();

  // Thread implementation.
  virtual void Run();

  WifiData wifi_data_;
  Mutex data_mutex_;
  // Event signalled to shut down the thread that polls for wifi data.
  Event stop_event_;
  // Whether we've successfully completed a scan for WiFi data.
  bool is_first_scan_complete_;

  DISALLOW_EVIL_CONSTRUCTORS(LinuxWifiDataProvider);
};

#endif  // GEARS_GEOLOCATION_WIFI_DATA_PROVIDER_LINUX_H__