blob: d2b633749cf851926248e521ae3576c4f7b4c96d [file] [log] [blame]
// Copyright 2014 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.
// A wifi data provider provides wifi data from the device that is used by a
// NetworkLocationProvider to obtain a position fix. We use a singleton
// instance of the wifi data provider manager, which is used by multiple
// NetworkLocationProvider objects.
// This file provides WifiDataProviderManager, which provides static methods to
// access the singleton instance. The singleton instance uses a private
// implementation of WifiDataProvider to abstract across platforms and also to
// allow mock providers to be used for testing.
#include <set>
#include "base/bind.h"
#include "base/callback.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/strings/string16.h"
#include "base/strings/string_util.h"
#include "device/geolocation/geolocation_export.h"
#include "device/geolocation/wifi_data.h"
namespace device {
class WifiDataProvider;
// A manager for wifi data providers.
// We use a singleton instance of this class which is shared by multiple network
// location providers. These location providers access the instance through the
// Register and Unregister methods.
class DEVICE_GEOLOCATION_EXPORT WifiDataProviderManager {
typedef WifiDataProvider* (*ImplFactoryFunction)(void);
// Sets the factory function which will be used by Register to create the
// implementation used by the singleton instance. This factory approach is
// used both to abstract accross platform-specific implementations and to
// inject mock implementations for testing.
static void SetFactoryForTesting(ImplFactoryFunction factory_function_in);
// Resets the factory function to the default.
static void ResetFactoryForTesting();
typedef base::Closure WifiDataUpdateCallback;
// Registers a callback, which will be run whenever new data is available.
// Instantiates the singleton if necessary, and always returns it.
static WifiDataProviderManager* Register(WifiDataUpdateCallback* callback);
// Removes a callback. If this is the last callback, deletes the singleton
// instance. Return value indicates success.
static bool Unregister(WifiDataUpdateCallback* callback);
// Provides whatever data the provider has, which may be nothing. Return
// value indicates whether this is all the data the provider could ever
// obtain.
bool GetData(WifiData* data);
// Private constructor and destructor, callers access singleton through
// Register and Unregister.
void AddCallback(WifiDataUpdateCallback* callback);
bool RemoveCallback(WifiDataUpdateCallback* callback);
bool has_callbacks() const;
void StartDataProvider();
void StopDataProvider();
static WifiDataProvider* DefaultFactoryFunction();
// The singleton-like instance of this class. (Not 'true' singleton, as it
// may go through multiple create/destroy/create cycles per process instance,
// e.g. when under test).
static WifiDataProviderManager* instance_;
// The factory function used to create the singleton instance.
static ImplFactoryFunction factory_function_;
// The internal implementation.
scoped_refptr<WifiDataProvider> impl_;
} // namespace device