Fixed a defect that allowed ancillary device providers to overwrite primary provider's data.

@@ -290,12 +290,17 @@ public class GossipDeviceStore
     private DeviceEvent updateDevice(ProviderId providerId,
                                      Device oldDevice,
                                      Device newDevice, Timestamp newTimestamp) {
-
         // We allow only certain attributes to trigger update
-        if (!Objects.equals(oldDevice.hwVersion(), newDevice.hwVersion()) ||
-            !Objects.equals(oldDevice.swVersion(), newDevice.swVersion()) ||
-            !AnnotationsUtil.isEqual(oldDevice.annotations(), newDevice.annotations())) {
-
+        boolean propertiesChanged =
+                !Objects.equals(oldDevice.hwVersion(), newDevice.hwVersion()) ||
+                        !Objects.equals(oldDevice.swVersion(), newDevice.swVersion());
+        boolean annotationsChanged =
+                !AnnotationsUtil.isEqual(oldDevice.annotations(), newDevice.annotations());
+
+        // Primary providers can respond to all changes, but ancillary ones
+        // should respond only to annotation changes.
+        if ((providerId.isAncillary() && annotationsChanged) ||
+                (!providerId.isAncillary() && (propertiesChanged || annotationsChanged))) {
             boolean replaced = devices.replace(newDevice.id(), oldDevice, newDevice);
             if (!replaced) {
                 verify(replaced,

@@ -70,15 +70,16 @@ public class SimpleDeviceStore
 
     public static final String DEVICE_NOT_FOUND = "Device with ID %s not found";
 
-    // collection of Description given from various providers
+    // Collection of Description given from various providers
     private final ConcurrentMap<DeviceId, Map<ProviderId, DeviceDescriptions>>
             deviceDescs = Maps.newConcurrentMap();
 
-    // cache of Device and Ports generated by compositing descriptions from providers
+    // Cache of Device and Ports generated by compositing descriptions from providers
     private final ConcurrentMap<DeviceId, Device> devices = Maps.newConcurrentMap();
-    private final ConcurrentMap<DeviceId, ConcurrentMap<PortNumber, Port>> devicePorts = Maps.newConcurrentMap();
+    private final ConcurrentMap<DeviceId, ConcurrentMap<PortNumber, Port>>
+            devicePorts = Maps.newConcurrentMap();
 
-    // available(=UP) devices
+    // Available (=UP) devices
     private final Set<DeviceId> availableDevices = Sets.newConcurrentHashSet();
 
 
@@ -115,13 +116,11 @@ public class SimpleDeviceStore
     public DeviceEvent createOrUpdateDevice(ProviderId providerId,
                                             DeviceId deviceId,
                                             DeviceDescription deviceDescription) {
-
         Map<ProviderId, DeviceDescriptions> providerDescs
                 = getOrCreateDeviceDescriptions(deviceId);
 
         synchronized (providerDescs) {
             // locking per device
-
             DeviceDescriptions descs
                     = getOrCreateProviderDeviceDescriptions(providerDescs,
                                                             providerId,
@@ -145,7 +144,6 @@ public class SimpleDeviceStore
     // Creates the device and returns the appropriate event if necessary.
     // Guarded by deviceDescs value (=Device lock)
     private DeviceEvent createDevice(ProviderId providerId, Device newDevice) {
-
         // update composed device cache
         Device oldDevice = devices.putIfAbsent(newDevice.id(), newDevice);
         verify(oldDevice == null,
@@ -162,14 +160,21 @@ public class SimpleDeviceStore
     // Updates the device and returns the appropriate event if necessary.
     // Guarded by deviceDescs value (=Device lock)
     private DeviceEvent updateDevice(ProviderId providerId, Device oldDevice, Device newDevice) {
-
         // We allow only certain attributes to trigger update
-        if (!Objects.equals(oldDevice.hwVersion(), newDevice.hwVersion()) ||
-            !Objects.equals(oldDevice.swVersion(), newDevice.swVersion()) ||
-            !AnnotationsUtil.isEqual(oldDevice.annotations(), newDevice.annotations())) {
+        boolean propertiesChanged =
+                !Objects.equals(oldDevice.hwVersion(), newDevice.hwVersion()) ||
+                        !Objects.equals(oldDevice.swVersion(), newDevice.swVersion());
+        boolean annotationsChanged =
+                !AnnotationsUtil.isEqual(oldDevice.annotations(), newDevice.annotations());
+
+        // Primary providers can respond to all changes, but ancillary ones
+        // should respond only to annotation changes.
+        if ((providerId.isAncillary() && annotationsChanged) ||
+                (!providerId.isAncillary() && (propertiesChanged || annotationsChanged))) {
 
             boolean replaced = devices.replace(newDevice.id(), oldDevice, newDevice);
             if (!replaced) {
+                // FIXME: Is the enclosing if required here?
                 verify(replaced,
                        "Replacing devices cache failed. PID:%s [expected:%s, found:%s, new=%s]",
                        providerId, oldDevice, devices.get(newDevice.id())
@@ -214,7 +219,6 @@ public class SimpleDeviceStore
     public List<DeviceEvent> updatePorts(ProviderId providerId,
                                          DeviceId deviceId,
                                          List<PortDescription> portDescriptions) {
-
         Device device = devices.get(deviceId);
         checkArgument(device != null, DEVICE_NOT_FOUND, deviceId);
 
@@ -327,7 +331,6 @@ public class SimpleDeviceStore
     private DeviceDescriptions getOrCreateProviderDeviceDescriptions(
             Map<ProviderId, DeviceDescriptions> device,
             ProviderId providerId, DeviceDescription deltaDesc) {
-
         synchronized (device) {
             DeviceDescriptions r = device.get(providerId);
             if (r == null) {
@@ -447,7 +450,7 @@ public class SimpleDeviceStore
             annotations = merge(annotations, e.getValue().getDeviceDesc().annotations());
         }
 
-        return new DefaultDevice(primary, deviceId , type, manufacturer,
+        return new DefaultDevice(primary, deviceId, type, manufacturer,
                                  hwVersion, swVersion, serialNumber,
                                  chassisId, annotations);
     }