Bug 1013012 - Support for js highAccuracy flag in geolocation. r=jdm

dom/src/geolocation/nsGeolocation.cpp

@@ -431,32 +431,28 @@ nsGeolocationRequest::Allow(JS::HandleValue aChoices)
     return NS_OK;
   }
 
-  nsCOMPtr<nsIDOMGeoPosition> lastPosition = gs->GetCachedPosition();
-  DOMTimeStamp cachedPositionTime;
-  if (lastPosition) {
-    lastPosition->GetTimestamp(&cachedPositionTime);
-  }
-
-  // check to see if we can use a cached value
-  // if the user has specified a maximumAge, return a cached value.
-
-  uint32_t maximumAge = 0;
-  if (mOptions) {
-    if (mOptions->mMaximumAge > 0) {
-      maximumAge = mOptions->mMaximumAge;
+  bool canUseCache = false;
+  CachedPositionAndAccuracy lastPosition = gs->GetCachedPosition();
+  if (lastPosition.position) {
+    DOMTimeStamp cachedPositionTime_ms;
+    lastPosition.position->GetTimestamp(&cachedPositionTime_ms);
+    // check to see if we can use a cached value
+    // if the user has specified a maximumAge, return a cached value.
+    if (mOptions && mOptions->mMaximumAge > 0) {
+      uint32_t maximumAge_ms = mOptions->mMaximumAge;
+      bool isCachedWithinRequestedAccuracy = WantsHighAccuracy() <= lastPosition.isHighAccuracy;
+      bool isCachedWithinRequestedTime =
+        DOMTimeStamp(PR_Now() / PR_USEC_PER_MSEC - maximumAge_ms) <= cachedPositionTime_ms;
+      canUseCache = isCachedWithinRequestedAccuracy && isCachedWithinRequestedTime;
     }
   }
+
   gs->UpdateAccuracy(WantsHighAccuracy());
-
-  bool canUseCache = lastPosition && maximumAge > 0 &&
-    (PRTime(PR_Now() / PR_USEC_PER_MSEC) - maximumAge <=
-    PRTime(cachedPositionTime));
-
   if (canUseCache) {
     // okay, we can return a cached position
     // getCurrentPosition requests serviced by the cache
     // will now be owned by the RequestSendLocationEvent
-    Update(lastPosition);
+    Update(lastPosition.position);
   }
 
   if (mIsWatchPositionRequest || !canUseCache) {
@@ -764,7 +760,7 @@ nsGeolocationService::HandleMozsettingValue(const bool aValue)
       // turn things off
       StopDevice();
       Update(nullptr);
-      mLastPosition = nullptr;
+      mLastPosition.position = nullptr;
       sGeoEnabled = false;
     } else {
       sGeoEnabled = true;
@@ -854,10 +850,11 @@ nsGeolocationService::NotifyError(uint16_t aErrorCode)
 void
 nsGeolocationService::SetCachedPosition(nsIDOMGeoPosition* aPosition)
 {
-  mLastPosition = aPosition;
+  mLastPosition.position = aPosition;
+  mLastPosition.isHighAccuracy = mHigherAccuracy;
 }
 
-nsIDOMGeoPosition*
+CachedPositionAndAccuracy
 nsGeolocationService::GetCachedPosition()
 {
   return mLastPosition;

dom/src/geolocation/nsGeolocation.h

@@ -45,6 +45,11 @@ typedef CallbackObjectHolder<PositionErrorCallback, nsIDOMGeoPositionErrorCallba
 }
 }
 
+struct CachedPositionAndAccuracy {
+  nsCOMPtr<nsIDOMGeoPosition> position;
+  bool isHighAccuracy;
+};
+
 /**
  * Singleton that manages the geolocation provider
  */
@@ -73,7 +78,7 @@ public:
   void RemoveLocator(mozilla::dom::Geolocation* locator);
 
   void SetCachedPosition(nsIDOMGeoPosition* aPosition);
-  nsIDOMGeoPosition* GetCachedPosition();
+  CachedPositionAndAccuracy GetCachedPosition();
 
   // Find and startup a geolocation device (gps, nmea, etc.)
   nsresult StartDevice(nsIPrincipal* aPrincipal);
@@ -106,7 +111,7 @@ private:
   nsTArray<mozilla::dom::Geolocation*> mGeolocators;
 
   // This is the last geo position that we have seen.
-  nsCOMPtr<nsIDOMGeoPosition> mLastPosition;
+  CachedPositionAndAccuracy mLastPosition;
 
   // Current state of requests for higher accuracy
   bool mHigherAccuracy;