| /* |
| * Copyright (C) 2013 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 com.android.systemui.statusbar; |
| |
| import android.content.BroadcastReceiver; |
| import android.content.ComponentName; |
| import android.content.ContentResolver; |
| import android.content.Context; |
| import android.content.Intent; |
| import android.content.IntentFilter; |
| import android.content.ServiceConnection; |
| import android.content.pm.PackageManager; |
| import android.database.ContentObserver; |
| import android.net.Uri; |
| import android.os.Bundle; |
| import android.os.Handler; |
| import android.os.IBinder; |
| import android.os.Message; |
| import android.os.RemoteException; |
| import android.os.UserHandle; |
| import android.provider.Settings; |
| import android.util.Log; |
| |
| import java.util.Arrays; |
| |
| /** |
| * Manages a persistent connection to a service component defined in a secure setting. |
| * |
| * <p>If a valid service component is specified in the secure setting, starts it up and keeps it |
| * running; handling setting changes, package updates, component disabling, and unexpected |
| * process termination. |
| * |
| * <p>Clients can listen for important events using the supplied {@link Callbacks}. |
| */ |
| public class ServiceMonitor { |
| private static final int RECHECK_DELAY = 2000; |
| private static final int WAIT_FOR_STOP = 500; |
| |
| public interface Callbacks { |
| /** The service does not exist or failed to bind */ |
| void onNoService(); |
| /** The service is about to start, this is a chance to perform cleanup and |
| * delay the start if necessary */ |
| long onServiceStartAttempt(); |
| } |
| |
| // internal handler + messages used to serialize access to internal state |
| public static final int MSG_START_SERVICE = 1; |
| public static final int MSG_CONTINUE_START_SERVICE = 2; |
| public static final int MSG_STOP_SERVICE = 3; |
| public static final int MSG_PACKAGE_INTENT = 4; |
| public static final int MSG_CHECK_BOUND = 5; |
| public static final int MSG_SERVICE_DISCONNECTED = 6; |
| |
| private final Handler mHandler = new Handler() { |
| public void handleMessage(Message msg) { |
| switch(msg.what) { |
| case MSG_START_SERVICE: |
| startService(); |
| break; |
| case MSG_CONTINUE_START_SERVICE: |
| continueStartService(); |
| break; |
| case MSG_STOP_SERVICE: |
| stopService(); |
| break; |
| case MSG_PACKAGE_INTENT: |
| packageIntent((Intent)msg.obj); |
| break; |
| case MSG_CHECK_BOUND: |
| checkBound(); |
| break; |
| case MSG_SERVICE_DISCONNECTED: |
| serviceDisconnected((ComponentName)msg.obj); |
| break; |
| } |
| } |
| }; |
| |
| private final ContentObserver mSettingObserver = new ContentObserver(mHandler) { |
| public void onChange(boolean selfChange) { |
| onChange(selfChange, null); |
| } |
| |
| public void onChange(boolean selfChange, Uri uri) { |
| if (mDebug) Log.d(mTag, "onChange selfChange=" + selfChange + " uri=" + uri); |
| ComponentName cn = getComponentNameFromSetting(); |
| if (cn == null && mServiceName == null || cn != null && cn.equals(mServiceName)) { |
| if (mDebug) Log.d(mTag, "skipping no-op restart"); |
| return; |
| } |
| if (mBound) { |
| mHandler.sendEmptyMessage(MSG_STOP_SERVICE); |
| } |
| mHandler.sendEmptyMessageDelayed(MSG_START_SERVICE, WAIT_FOR_STOP); |
| } |
| }; |
| |
| private final class SC implements ServiceConnection, IBinder.DeathRecipient { |
| private ComponentName mName; |
| private IBinder mService; |
| |
| public void onServiceConnected(ComponentName name, IBinder service) { |
| if (mDebug) Log.d(mTag, "onServiceConnected name=" + name + " service=" + service); |
| mName = name; |
| mService = service; |
| try { |
| service.linkToDeath(this, 0); |
| } catch (RemoteException e) { |
| Log.w(mTag, "Error linking to death", e); |
| } |
| } |
| |
| public void onServiceDisconnected(ComponentName name) { |
| if (mDebug) Log.d(mTag, "onServiceDisconnected name=" + name); |
| boolean unlinked = mService.unlinkToDeath(this, 0); |
| if (mDebug) Log.d(mTag, " unlinked=" + unlinked); |
| mHandler.sendMessage(mHandler.obtainMessage(MSG_SERVICE_DISCONNECTED, mName)); |
| } |
| |
| public void binderDied() { |
| if (mDebug) Log.d(mTag, "binderDied"); |
| mHandler.sendMessage(mHandler.obtainMessage(MSG_SERVICE_DISCONNECTED, mName)); |
| } |
| } |
| |
| private final BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() { |
| public void onReceive(Context context, Intent intent) { |
| String pkg = intent.getData().getSchemeSpecificPart(); |
| if (mServiceName != null && mServiceName.getPackageName().equals(pkg)) { |
| mHandler.sendMessage(mHandler.obtainMessage(MSG_PACKAGE_INTENT, intent)); |
| } |
| } |
| }; |
| |
| private final String mTag; |
| private final boolean mDebug; |
| |
| private final Context mContext; |
| private final String mSettingKey; |
| private final Callbacks mCallbacks; |
| |
| private ComponentName mServiceName; |
| private SC mServiceConnection; |
| private boolean mBound; |
| |
| public ServiceMonitor(String ownerTag, boolean debug, |
| Context context, String settingKey, Callbacks callbacks) { |
| mTag = ownerTag + ".ServiceMonitor"; |
| mDebug = debug; |
| mContext = context; |
| mSettingKey = settingKey; |
| mCallbacks = callbacks; |
| } |
| |
| public void start() { |
| // listen for setting changes |
| ContentResolver cr = mContext.getContentResolver(); |
| cr.registerContentObserver(Settings.Secure.getUriFor(mSettingKey), |
| false /*notifyForDescendents*/, mSettingObserver, UserHandle.USER_ALL); |
| |
| // listen for package/component changes |
| IntentFilter filter = new IntentFilter(); |
| filter.addAction(Intent.ACTION_PACKAGE_ADDED); |
| filter.addAction(Intent.ACTION_PACKAGE_CHANGED); |
| filter.addAction(Intent.ACTION_PACKAGE_REMOVED); |
| filter.addDataScheme("package"); |
| mContext.registerReceiver(mBroadcastReceiver, filter); |
| |
| mHandler.sendEmptyMessage(MSG_START_SERVICE); |
| } |
| |
| private ComponentName getComponentNameFromSetting() { |
| String cn = Settings.Secure.getStringForUser(mContext.getContentResolver(), |
| mSettingKey, UserHandle.USER_CURRENT); |
| return cn == null ? null : ComponentName.unflattenFromString(cn); |
| } |
| |
| // everything below is called on the handler |
| |
| private void packageIntent(Intent intent) { |
| if (mDebug) Log.d(mTag, "packageIntent intent=" + intent |
| + " extras=" + bundleToString(intent.getExtras())); |
| if (Intent.ACTION_PACKAGE_ADDED.equals(intent.getAction())) { |
| mHandler.sendEmptyMessage(MSG_START_SERVICE); |
| } else if (Intent.ACTION_PACKAGE_CHANGED.equals(intent.getAction()) |
| || Intent.ACTION_PACKAGE_REMOVED.equals(intent.getAction())) { |
| final PackageManager pm = mContext.getPackageManager(); |
| final boolean serviceEnabled = isPackageAvailable() |
| && pm.getApplicationEnabledSetting(mServiceName.getPackageName()) |
| != PackageManager.COMPONENT_ENABLED_STATE_DISABLED |
| && pm.getComponentEnabledSetting(mServiceName) |
| != PackageManager.COMPONENT_ENABLED_STATE_DISABLED; |
| if (mBound && !serviceEnabled) { |
| stopService(); |
| scheduleCheckBound(); |
| } else if (!mBound && serviceEnabled) { |
| startService(); |
| } |
| } |
| } |
| |
| private void stopService() { |
| if (mDebug) Log.d(mTag, "stopService"); |
| boolean stopped = mContext.stopService(new Intent().setComponent(mServiceName)); |
| if (mDebug) Log.d(mTag, " stopped=" + stopped); |
| mContext.unbindService(mServiceConnection); |
| mBound = false; |
| } |
| |
| private void startService() { |
| mServiceName = getComponentNameFromSetting(); |
| if (mDebug) Log.d(mTag, "startService mServiceName=" + mServiceName); |
| if (mServiceName == null) { |
| mBound = false; |
| mCallbacks.onNoService(); |
| } else { |
| long delay = mCallbacks.onServiceStartAttempt(); |
| mHandler.sendEmptyMessageDelayed(MSG_CONTINUE_START_SERVICE, delay); |
| } |
| } |
| |
| private void continueStartService() { |
| if (mDebug) Log.d(mTag, "continueStartService"); |
| Intent intent = new Intent().setComponent(mServiceName); |
| try { |
| mServiceConnection = new SC(); |
| mBound = mContext.bindService(intent, mServiceConnection, Context.BIND_AUTO_CREATE); |
| if (mDebug) Log.d(mTag, "mBound: " + mBound); |
| } catch (Throwable t) { |
| Log.w(mTag, "Error binding to service: " + mServiceName, t); |
| } |
| if (!mBound) { |
| mCallbacks.onNoService(); |
| } |
| } |
| |
| private void serviceDisconnected(ComponentName serviceName) { |
| if (mDebug) Log.d(mTag, "serviceDisconnected serviceName=" + serviceName |
| + " mServiceName=" + mServiceName); |
| if (serviceName.equals(mServiceName)) { |
| mBound = false; |
| scheduleCheckBound(); |
| } |
| } |
| |
| private void checkBound() { |
| if (mDebug) Log.d(mTag, "checkBound mBound=" + mBound); |
| if (!mBound) { |
| startService(); |
| } |
| } |
| |
| private void scheduleCheckBound() { |
| mHandler.removeMessages(MSG_CHECK_BOUND); |
| mHandler.sendEmptyMessageDelayed(MSG_CHECK_BOUND, RECHECK_DELAY); |
| } |
| |
| private static String bundleToString(Bundle bundle) { |
| if (bundle == null) return null; |
| StringBuilder sb = new StringBuilder("{"); |
| for (String key : bundle.keySet()) { |
| if (sb.length() > 1) sb.append(','); |
| Object v = bundle.get(key); |
| v = (v instanceof String[]) ? Arrays.asList((String[]) v) : v; |
| sb.append(key).append('=').append(v); |
| } |
| return sb.append('}').toString(); |
| } |
| |
| public ComponentName getComponent() { |
| return getComponentNameFromSetting(); |
| } |
| |
| public void setComponent(ComponentName component) { |
| final String setting = component == null ? null : component.flattenToShortString(); |
| Settings.Secure.putStringForUser(mContext.getContentResolver(), |
| mSettingKey, setting, UserHandle.USER_CURRENT); |
| } |
| |
| public boolean isPackageAvailable() { |
| final ComponentName component = getComponent(); |
| if (component == null) return false; |
| try { |
| return mContext.getPackageManager().isPackageAvailable(component.getPackageName()); |
| } catch (RuntimeException e) { |
| Log.w(mTag, "Error checking package availability", e); |
| return false; |
| } |
| } |
| } |