| /* |
| * Copyright (C) 2019 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package android.ext.services.watchdog; |
| |
| import android.net.ConnectivityManager; |
| import android.net.Network; |
| import android.net.NetworkCapabilities; |
| import android.net.NetworkRequest; |
| import android.service.watchdog.ExplicitHealthCheckService; |
| |
| import com.android.internal.annotations.GuardedBy; |
| |
| /** |
| * Observes the network stack via the ConnectivityManager. |
| */ |
| final class NetworkChecker extends ConnectivityManager.NetworkCallback |
| implements ExplicitHealthChecker { |
| private static final String TAG = "NetworkChecker"; |
| |
| private final Object mLock = new Object(); |
| private final ExplicitHealthCheckService mService; |
| private final String mPackageName; |
| @GuardedBy("mLock") |
| private boolean mIsPending; |
| |
| NetworkChecker(ExplicitHealthCheckService service, String packageName) { |
| mService = service; |
| mPackageName = packageName; |
| } |
| |
| @Override |
| public void request() { |
| synchronized (mLock) { |
| if (mIsPending) { |
| return; |
| } |
| mService.getSystemService(ConnectivityManager.class).registerNetworkCallback( |
| new NetworkRequest.Builder().build(), this); |
| mIsPending = true; |
| } |
| } |
| |
| @Override |
| public void cancel() { |
| synchronized (mLock) { |
| if (!mIsPending) { |
| return; |
| } |
| mService.getSystemService(ConnectivityManager.class).unregisterNetworkCallback(this); |
| mIsPending = false; |
| } |
| } |
| |
| @Override |
| public boolean isPending() { |
| synchronized (mLock) { |
| return mIsPending; |
| } |
| } |
| |
| @Override |
| public String getPackageName() { |
| return mPackageName; |
| } |
| |
| // TODO(b/120598832): Also monitor NetworkCallback#onAvailable to see if we have any |
| // available networks that may be unusable. This could be additional signal to our heuristics |
| @Override |
| public void onCapabilitiesChanged(Network network, NetworkCapabilities capabilities) { |
| synchronized (mLock) { |
| if (mIsPending |
| && capabilities.hasCapability(NetworkCapabilities.NET_CAPABILITY_VALIDATED)) { |
| mService.notifyHealthCheckPassed(mPackageName); |
| cancel(); |
| } |
| } |
| } |
| } |