net/base/network_change_notifier.cc

   1 // Copyright (c) 2011 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 "net/base/network_change_notifier.h"
   6 #include "net/base/network_change_notifier_factory.h"
   7 #include "build/build_config.h"
   8 #if defined(OS_WIN)
   9 #include "net/base/network_change_notifier_win.h"
  10 #elif defined(OS_LINUX) || defined(OS_ANDROID)
  11 #include "net/base/network_change_notifier_linux.h"
  12 #elif defined(OS_MACOSX)
  13 #include "net/base/network_change_notifier_mac.h"
  14 #endif
  15
  16 namespace net {
  17
  18 namespace {
  19
  20 // The actual singleton notifier.  The class contract forbids usage of the API
  21 // in ways that would require us to place locks around access to this object.
  22 // (The prohibition on global non-POD objects makes it tricky to do such a thing
  23 // anyway.)
  24 NetworkChangeNotifier* g_network_change_notifier = NULL;
  25
  26 // Class factory singleton.
  27 NetworkChangeNotifierFactory* g_network_change_notifier_factory = NULL;
  28
  29 class MockNetworkChangeNotifier : public NetworkChangeNotifier {
  30  public:
  31   virtual bool IsCurrentlyOffline() const { return false; }
  32 };
  33
  34 }  // namespace
  35
  36 NetworkChangeNotifier::~NetworkChangeNotifier() {
  37   DCHECK_EQ(this, g_network_change_notifier);
  38   g_network_change_notifier = NULL;
  39 }
  40
  41 // static
  42 void NetworkChangeNotifier::SetFactory(
  43     NetworkChangeNotifierFactory* factory) {
  44   CHECK(!g_network_change_notifier_factory);
  45   g_network_change_notifier_factory = factory;
  46 }
  47
  48 // static
  49 NetworkChangeNotifier* NetworkChangeNotifier::Create() {
  50   if (g_network_change_notifier_factory)
  51     return g_network_change_notifier_factory->CreateInstance();
  52
  53 #if defined(OS_WIN)
  54   NetworkChangeNotifierWin* network_change_notifier =
  55       new NetworkChangeNotifierWin();
  56   network_change_notifier->WatchForAddressChange();
  57   return network_change_notifier;
  58 #elif defined(OS_CHROMEOS)
  59   // ChromeOS builds MUST use its own class factory.
  60   CHECK(false);
  61   return NULL;
  62 #elif defined(OS_LINUX) || defined(OS_ANDROID)
  63   return NetworkChangeNotifierLinux::Create();
  64 #elif defined(OS_MACOSX)
  65   return new NetworkChangeNotifierMac();
  66 #else
  67   NOTIMPLEMENTED();
  68   return NULL;
  69 #endif
  70 }
  71
  72 // static
  73 bool NetworkChangeNotifier::IsOffline() {
  74   return g_network_change_notifier &&
  75          g_network_change_notifier->IsCurrentlyOffline();
  76 }
  77
  78 // static
  79 NetworkChangeNotifier* NetworkChangeNotifier::CreateMock() {
  80   return new MockNetworkChangeNotifier();
  81 }
  82
  83 void NetworkChangeNotifier::AddIPAddressObserver(IPAddressObserver* observer) {
  84   if (g_network_change_notifier)
  85     g_network_change_notifier->ip_address_observer_list_->AddObserver(observer);
  86 }
  87
  88 void NetworkChangeNotifier::AddOnlineStateObserver(
  89     OnlineStateObserver* observer) {
  90   if (g_network_change_notifier) {
  91     g_network_change_notifier->online_state_observer_list_->AddObserver(
  92         observer);
  93   }
  94 }
  95
  96 void NetworkChangeNotifier::AddDNSObserver(DNSObserver* observer) {
  97   if (g_network_change_notifier) {
  98     g_network_change_notifier->resolver_state_observer_list_->AddObserver(
  99         observer);
 100   }
 101 }
 102
 103 void NetworkChangeNotifier::RemoveIPAddressObserver(
 104     IPAddressObserver* observer) {
 105   if (g_network_change_notifier) {
 106     g_network_change_notifier->ip_address_observer_list_->RemoveObserver(
 107         observer);
 108   }
 109 }
 110
 111 void NetworkChangeNotifier::RemoveOnlineStateObserver(
 112     OnlineStateObserver* observer) {
 113   if (g_network_change_notifier) {
 114     g_network_change_notifier->online_state_observer_list_->RemoveObserver(
 115         observer);
 116   }
 117 }
 118
 119 void NetworkChangeNotifier::RemoveDNSObserver(DNSObserver* observer) {
 120   if (g_network_change_notifier) {
 121     g_network_change_notifier->resolver_state_observer_list_->RemoveObserver(
 122         observer);
 123   }
 124 }
 125
 126 NetworkChangeNotifier::NetworkChangeNotifier()
 127     : ip_address_observer_list_(
 128         new ObserverListThreadSafe<IPAddressObserver>(
 129             ObserverListBase<IPAddressObserver>::NOTIFY_EXISTING_ONLY)),
 130       online_state_observer_list_(
 131         new ObserverListThreadSafe<OnlineStateObserver>(
 132             ObserverListBase<OnlineStateObserver>::NOTIFY_EXISTING_ONLY)),
 133       resolver_state_observer_list_(
 134         new ObserverListThreadSafe<DNSObserver>(
 135             ObserverListBase<DNSObserver>::NOTIFY_EXISTING_ONLY)) {
 136   DCHECK(!g_network_change_notifier);
 137   g_network_change_notifier = this;
 138 }
 139
 140 void NetworkChangeNotifier::NotifyObserversOfIPAddressChange() {
 141   if (g_network_change_notifier) {
 142     g_network_change_notifier->ip_address_observer_list_->Notify(
 143         &IPAddressObserver::OnIPAddressChanged);
 144   }
 145 }
 146
 147 void NetworkChangeNotifier::NotifyObserversOfDNSChange() {
 148   if (g_network_change_notifier) {
 149     g_network_change_notifier->resolver_state_observer_list_->Notify(
 150         &DNSObserver::OnDNSChanged);
 151   }
 152 }
 153
 154 void NetworkChangeNotifier::NotifyObserversOfOnlineStateChange() {
 155   if (g_network_change_notifier) {
 156     g_network_change_notifier->online_state_observer_list_->Notify(
 157         &OnlineStateObserver::OnOnlineStateChanged, !IsOffline());
 158   }
 159 }
 160
 161 NetworkChangeNotifier::DisableForTest::DisableForTest()
 162     : network_change_notifier_(g_network_change_notifier) {
 163   DCHECK(g_network_change_notifier);
 164   g_network_change_notifier = NULL;
 165 }
 166
 167 NetworkChangeNotifier::DisableForTest::~DisableForTest() {
 168   DCHECK(!g_network_change_notifier);
 169   g_network_change_notifier = network_change_notifier_;
 170 }
 171
 172 }  // namespace net