Handle neighbor lost event am: e600bef8f9

Original change: https://android-review.googlesource.com/c/platform/frameworks/opt/net/ethernet/+/1586426

Change-Id: Ic66ac799dfd9287dcd7d5ca6912f6b4a6e07ecad

service-t/src/com/android/server/ethernet/EthernetNetworkFactory.java

@@ -346,6 +346,11 @@ public class EthernetNetworkFactory extends NetworkFactory {
                 mHandler.post(() -> updateLinkProperties(newLp));
             }
 
+            @Override
+            public void onReachabilityLost(String logMsg) {
+                mHandler.post(() -> updateNeighborLostEvent(logMsg));
+            }
+
             @Override
             public void onQuit() {
                 mIpClient = null;
@@ -479,6 +484,17 @@ public class EthernetNetworkFactory extends NetworkFactory {
             }
         }
 
+        void updateNeighborLostEvent(String logMsg) {
+            Log.i(TAG, "updateNeighborLostEvent " + logMsg);
+            // Reachability lost will be seen only if the gateway is not reachable.
+            // Since ethernet FW doesn't have the mechanism to scan for new networks
+            // like WiFi, simply restart.
+            // If there is a better network, that will become default and apps
+            // will be able to use internet. If ethernet gets connected again,
+            // and has backhaul connectivity, it will become default.
+            restart();
+        }
+
         /** Returns true if state has been modified */
         boolean updateLinkState(boolean up) {
             if (mLinkUp == up) return false;

tests/ethernet/java/com/android/server/ethernet/EthernetNetworkFactoryTest.java

@@ -434,4 +434,20 @@ public class EthernetNetworkFactoryTest {
                 ConnectivityManager.TYPE_NONE);
         mNetFactory.removeInterface(iface);
     }
+
+    @Test
+    public void testReachabilityLoss() throws Exception {
+        String iface = "eth0";
+        createAndVerifyProvisionedInterface(iface);
+
+        mIpClientCallbacks.onReachabilityLost("ReachabilityLost");
+        mLooper.dispatchAll();
+
+        // Reachability loss should trigger a stop and start, since the interface is still there
+        verify(mIpClient).shutdown();
+        verify(mNetworkAgent).unregister();
+
+        verify(mDeps).makeIpClient(any(Context.class), anyString(), any());
+        verify(mIpClient).startProvisioning(any());
+    }
 }