content/browser/geolocation/wifi_data_provider_manager.cc

   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 #include "content/browser/geolocation/wifi_data_provider_manager.h"
   6
   7 #include "content/browser/geolocation/wifi_data_provider.h"
   8
   9 namespace content {
  10
  11 // static
  12 WifiDataProviderManager* WifiDataProviderManager::instance_ = NULL;
  13
  14 // static
  15 WifiDataProviderManager::ImplFactoryFunction
  16     WifiDataProviderManager::factory_function_ = DefaultFactoryFunction;
  17
  18 // static
  19 void WifiDataProviderManager::SetFactoryForTesting(
  20     ImplFactoryFunction factory_function_in) {
  21   factory_function_ = factory_function_in;
  22 }
  23
  24 // static
  25 void WifiDataProviderManager::ResetFactoryForTesting() {
  26   factory_function_ = DefaultFactoryFunction;
  27 }
  28
  29 // static
  30 WifiDataProviderManager* WifiDataProviderManager::Register(
  31     WifiDataUpdateCallback* callback) {
  32   bool need_to_start_data_provider = false;
  33   if (!instance_) {
  34     instance_ = new WifiDataProviderManager();
  35     need_to_start_data_provider = true;
  36   }
  37   DCHECK(instance_);
  38   instance_->AddCallback(callback);
  39   // Start the provider after adding the callback, to avoid any race in
  40   // it running early.
  41   if (need_to_start_data_provider)
  42     instance_->StartDataProvider();
  43   return instance_;
  44 }
  45
  46 // static
  47 bool WifiDataProviderManager::Unregister(WifiDataUpdateCallback* callback) {
  48   DCHECK(instance_);
  49   DCHECK(instance_->has_callbacks());
  50   if (!instance_->RemoveCallback(callback)) {
  51     return false;
  52   }
  53   if (!instance_->has_callbacks()) {
  54     // Must stop the data provider (and any implementation threads) before
  55     // destroying to avoid any race conditions in access to the provider in
  56     // the destructor chain.
  57     instance_->StopDataProvider();
  58     delete instance_;
  59     instance_ = NULL;
  60   }
  61   return true;
  62 }
  63
  64 WifiDataProviderManager::WifiDataProviderManager() {
  65   DCHECK(factory_function_);
  66   impl_ = (*factory_function_)();
  67   DCHECK(impl_.get());
  68 }
  69
  70 WifiDataProviderManager::~WifiDataProviderManager() {
  71   DCHECK(impl_.get());
  72 }
  73
  74 bool WifiDataProviderManager::GetData(WifiData* data) {
  75   return impl_->GetData(data);
  76 }
  77
  78 void WifiDataProviderManager::AddCallback(WifiDataUpdateCallback* callback) {
  79   impl_->AddCallback(callback);
  80 }
  81
  82 bool WifiDataProviderManager::RemoveCallback(WifiDataUpdateCallback* callback) {
  83   return impl_->RemoveCallback(callback);
  84 }
  85
  86 bool WifiDataProviderManager::has_callbacks() const {
  87   return impl_->has_callbacks();
  88 }
  89
  90 void WifiDataProviderManager::StartDataProvider() {
  91   impl_->StartDataProvider();
  92 }
  93
  94 void WifiDataProviderManager::StopDataProvider() {
  95   impl_->StopDataProvider();
  96 }
  97
  98 }  // namespace content