Bug 678694 - (7/7) Interaction between DOM and hal. r=sicking

The battery status is coming from hal and when there is an update, hal informs
the DOM which then dispatch the appropriate event.

dom/base/Navigator.cpp

@@ -102,6 +102,10 @@ Navigator::~Navigator()
   if (mPlugins) {
     mPlugins->Invalidate();
   }
+
+  if (mBatteryManager) {
+    mBatteryManager->Shutdown();
+  }
 }
 
 NS_INTERFACE_MAP_BEGIN(Navigator)
@@ -136,6 +140,11 @@ Navigator::SetDocShell(nsIDocShell* aDocShell)
     mNotification->Shutdown();
     mNotification = nsnull;
   }
+
+  if (mBatteryManager) {
+    mBatteryManager->Shutdown();
+    mBatteryManager = nsnull;
+  }
 }
 
 //*****************************************************************************
@@ -513,6 +522,7 @@ Navigator::LoadingNewDocument()
   }
 
   if (mBatteryManager) {
+    mBatteryManager->Shutdown();
     mBatteryManager = nsnull;
   }
 }
@@ -740,6 +750,7 @@ Navigator::GetMozBattery(nsIDOMBatteryManager** aBattery)
 {
   if (!mBatteryManager) {
     mBatteryManager = new battery::BatteryManager();
+    mBatteryManager->Init();
   }
 
   NS_ADDREF(*aBattery = mBatteryManager);

dom/base/Navigator.h

@@ -49,7 +49,6 @@
 #include "nsIDOMClientInformation.h"
 #include "nsIDOMNavigatorBattery.h"
 #include "nsAutoPtr.h"
-#include "nsIDOMBatteryManager.h"
 
 class nsPluginArray;
 class nsMimeTypeArray;
@@ -64,6 +63,10 @@ class nsIDocShell;
 namespace mozilla {
 namespace dom {
 
+namespace battery {
+class BatteryManager;
+} // namespace battery
+
 class Navigator : public nsIDOMNavigator,
                   public nsIDOMClientInformation,
                   public nsIDOMNavigatorGeolocation,
@@ -103,7 +106,7 @@ private:
   nsRefPtr<nsPluginArray> mPlugins;
   nsRefPtr<nsGeolocation> mGeolocation;
   nsRefPtr<nsDesktopNotificationCenter> mNotification;
-  nsCOMPtr<nsIDOMBatteryManager> mBatteryManager;
+  nsRefPtr<battery::BatteryManager> mBatteryManager;
   nsIDocShell* mDocShell; // weak reference
 };
 

dom/battery/BatteryManager.cpp

@@ -35,9 +35,18 @@
  *
  * ***** END LICENSE BLOCK ***** */
 
+#include "mozilla/Hal.h"
 #include "BatteryManager.h"
 #include "nsIDOMClassInfo.h"
 #include "Constants.h"
+#include "nsDOMEvent.h"
+
+/**
+ * We have to use macros here because our leak analysis tool things we are
+ * leaking strings when we have |static const nsString|. Sad :(
+ */
+#define LEVELCHANGE_EVENT_NAME    NS_LITERAL_STRING("levelchange")
+#define CHARGINGCHANGE_EVENT_NAME NS_LITERAL_STRING("chargingchange")
 
 DOMCI_DATA(BatteryManager, mozilla::dom::battery::BatteryManager)
 
@@ -80,6 +89,25 @@ BatteryManager::~BatteryManager()
   }
 }
 
+void
+BatteryManager::Init()
+{
+  hal::RegisterBatteryObserver(this);
+
+  hal::BatteryInformation* batteryInfo = new hal::BatteryInformation();
+  hal::GetCurrentBatteryInformation(batteryInfo);
+
+  UpdateFromBatteryInfo(*batteryInfo);
+
+  delete batteryInfo;
+}
+
+void
+BatteryManager::Shutdown()
+{
+  hal::UnregisterBatteryObserver(this);
+}
+
 NS_IMETHODIMP
 BatteryManager::GetCharging(bool* aCharging)
 {
@@ -105,8 +133,8 @@ BatteryManager::GetOnlevelchange(nsIDOMEventListener** aOnlevelchange)
 NS_IMETHODIMP
 BatteryManager::SetOnlevelchange(nsIDOMEventListener* aOnlevelchange)
 {
-  return RemoveAddEventListener(NS_LITERAL_STRING("levelchange"),
-                                mOnLevelChangeListener, aOnlevelchange);
+  return RemoveAddEventListener(LEVELCHANGE_EVENT_NAME, mOnLevelChangeListener,
+                                aOnlevelchange);
 }
 
 NS_IMETHODIMP
@@ -118,10 +146,51 @@ BatteryManager::GetOnchargingchange(nsIDOMEventListener** aOnchargingchange)
 NS_IMETHODIMP
 BatteryManager::SetOnchargingchange(nsIDOMEventListener* aOnchargingchange)
 {
-  return RemoveAddEventListener(NS_LITERAL_STRING("chargingchange"),
+  return RemoveAddEventListener(CHARGINGCHANGE_EVENT_NAME,
                                 mOnChargingChangeListener, aOnchargingchange);
 }
 
+nsresult
+BatteryManager::DispatchTrustedEventToSelf(const nsAString& aEventName)
+{
+  nsRefPtr<nsDOMEvent> event = new nsDOMEvent(nsnull, nsnull);
+  nsresult rv = event->InitEvent(aEventName, false, false);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  rv = event->SetTrusted(PR_TRUE);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  bool dummy;
+  rv = DispatchEvent(event, &dummy);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  return NS_OK;
+}
+
+void
+BatteryManager::UpdateFromBatteryInfo(const hal::BatteryInformation& aBatteryInfo)
+{
+  mLevel = aBatteryInfo.level();
+  mCharging = aBatteryInfo.charging();
+}
+
+void
+BatteryManager::Notify(const hal::BatteryInformation& aBatteryInfo)
+{
+  float previousLevel = mLevel;
+  bool previousCharging = mCharging;
+
+  UpdateFromBatteryInfo(aBatteryInfo);
+
+  if (previousCharging != mCharging) {
+    DispatchTrustedEventToSelf(CHARGINGCHANGE_EVENT_NAME);
+  }
+
+  if (previousLevel != mLevel) {
+    DispatchTrustedEventToSelf(LEVELCHANGE_EVENT_NAME);
+  }
+}
+
 } // namespace battery
 } // namespace dom
 } // namespace mozilla

dom/battery/BatteryManager.h

@@ -41,13 +41,21 @@
 #include "nsIDOMBatteryManager.h"
 #include "nsDOMEventTargetHelper.h"
 #include "nsCycleCollectionParticipant.h"
+#include "mozilla/Observer.h"
+#include "Types.h"
 
 namespace mozilla {
+
+namespace hal {
+class BatteryInformation;
+} // namespace hal
+
 namespace dom {
 namespace battery {
 
 class BatteryManager : public nsIDOMBatteryManager
                      , public nsDOMEventTargetHelper
+                     , public BatteryObserver
 {
 public:
   NS_DECL_ISUPPORTS
@@ -57,10 +65,27 @@ public:
   BatteryManager();
   virtual ~BatteryManager();
 
+  void Init();
+  void Shutdown();
+
+  // For IObserver.
+  void Notify(const hal::BatteryInformation& aBatteryInfo);
+
   NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(BatteryManager,
                                            nsDOMEventTargetHelper)
 
 private:
+  /**
+   * Dispatch a trusted non-cancellable and non-bubbling event to itself.
+   */
+  nsresult DispatchTrustedEventToSelf(const nsAString& aEventName);
+
+  /**
+   * Update the battery information stored in the battery manager object using
+   * a battery information object.
+   */
+  void UpdateFromBatteryInfo(const hal::BatteryInformation& aBatteryInfo);
+
   float mLevel;
   bool  mCharging;
 

dom/battery/Makefile.in

@@ -72,4 +72,6 @@ ifdef ENABLE_TESTS
 DIRS += test
 endif
 
+include $(topsrcdir)/config/config.mk
+include $(topsrcdir)/ipc/chromium/chromium-config.mk
 include $(topsrcdir)/config/rules.mk