| /* |
| * Copyright (C) 2012 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.server; |
| |
| import android.content.ComponentName; |
| import android.content.Context; |
| import android.content.Intent; |
| import android.content.ServiceConnection; |
| import android.content.pm.PackageInfo; |
| import android.content.pm.PackageManager; |
| import android.content.pm.PackageManager.NameNotFoundException; |
| import android.content.pm.ResolveInfo; |
| import android.content.pm.Signature; |
| import android.os.Handler; |
| import android.os.IBinder; |
| import android.util.Log; |
| |
| import com.android.internal.content.PackageMonitor; |
| |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.HashSet; |
| import java.util.List; |
| |
| /** |
| * Find the best Service, and bind to it. |
| * Handles run-time package changes. |
| */ |
| public class ServiceWatcher implements ServiceConnection { |
| private static final boolean D = false; |
| private static final String EXTRA_VERSION = "version"; |
| |
| private final String mTag; |
| private final Context mContext; |
| private final PackageManager mPm; |
| private final List<HashSet<Signature>> mSignatureSets; |
| private final String mAction; |
| private final Runnable mNewServiceWork; |
| private final Handler mHandler; |
| |
| private Object mLock = new Object(); |
| |
| // all fields below synchronized on mLock |
| private IBinder mBinder; // connected service |
| private String mPackageName; // current best package |
| private int mVersion; // current best version |
| |
| public ServiceWatcher(Context context, String logTag, String action, |
| List<String> initialPackageNames, Runnable newServiceWork, Handler handler) { |
| mContext = context; |
| mTag = logTag; |
| mAction = action; |
| mPm = mContext.getPackageManager(); |
| mNewServiceWork = newServiceWork; |
| mHandler = handler; |
| |
| mSignatureSets = new ArrayList<HashSet<Signature>>(); |
| for (int i=0; i < initialPackageNames.size(); i++) { |
| String pkg = initialPackageNames.get(i); |
| HashSet<Signature> set = new HashSet<Signature>(); |
| try { |
| Signature[] sigs = |
| mPm.getPackageInfo(pkg, PackageManager.GET_SIGNATURES).signatures; |
| set.addAll(Arrays.asList(sigs)); |
| mSignatureSets.add(set); |
| } catch (NameNotFoundException e) { |
| Log.w(logTag, pkg + " not found"); |
| } |
| } |
| |
| } |
| |
| public boolean start() { |
| if (!bindBestPackage(null)) return false; |
| |
| mPackageMonitor.register(mContext, null, true); |
| return true; |
| } |
| |
| /** |
| * Searches and binds to the best package, or do nothing |
| * if the best package is already bound. |
| * Only checks the named package, or checks all packages if it |
| * is null. |
| * Return true if a new package was found to bind to. |
| */ |
| private boolean bindBestPackage(String justCheckThisPackage) { |
| Intent intent = new Intent(mAction); |
| if (justCheckThisPackage != null) { |
| intent.setPackage(justCheckThisPackage); |
| } |
| List<ResolveInfo> rInfos = mPm.queryIntentServices(new Intent(mAction), |
| PackageManager.GET_META_DATA); |
| int bestVersion = Integer.MIN_VALUE; |
| String bestPackage = null; |
| for (ResolveInfo rInfo : rInfos) { |
| String packageName = rInfo.serviceInfo.packageName; |
| |
| // check signature |
| try { |
| PackageInfo pInfo; |
| pInfo = mPm.getPackageInfo(packageName, PackageManager.GET_SIGNATURES); |
| if (!isSignatureMatch(pInfo.signatures)) { |
| Log.w(mTag, packageName + " resolves service " + mAction + |
| ", but has wrong signature, ignoring"); |
| continue; |
| } |
| } catch (NameNotFoundException e) { |
| Log.wtf(mTag, e); |
| continue; |
| } |
| |
| // check version |
| int version = 0; |
| if (rInfo.serviceInfo.metaData != null) { |
| version = rInfo.serviceInfo.metaData.getInt(EXTRA_VERSION, 0); |
| } |
| if (version > mVersion) { |
| bestVersion = version; |
| bestPackage = packageName; |
| } |
| } |
| |
| if (D) Log.d(mTag, String.format("bindBestPackage %s found %d, %s", |
| (justCheckThisPackage == null ? "" : "(" + justCheckThisPackage + ") "), |
| rInfos.size(), |
| (bestPackage == null ? "no new best package" : "new best packge: " + bestPackage))); |
| |
| if (bestPackage != null) { |
| bindToPackage(bestPackage, bestVersion); |
| return true; |
| } |
| return false; |
| } |
| |
| private void unbind() { |
| String pkg; |
| synchronized (mLock) { |
| pkg = mPackageName; |
| mPackageName = null; |
| mVersion = Integer.MIN_VALUE; |
| } |
| if (pkg != null) { |
| if (D) Log.d(mTag, "unbinding " + pkg); |
| mContext.unbindService(this); |
| } |
| } |
| |
| private void bindToPackage(String packageName, int version) { |
| unbind(); |
| Intent intent = new Intent(mAction); |
| intent.setPackage(packageName); |
| synchronized (mLock) { |
| mPackageName = packageName; |
| mVersion = version; |
| } |
| if (D) Log.d(mTag, "binding " + packageName + " (version " + version + ")"); |
| mContext.bindService(intent, this, Context.BIND_AUTO_CREATE | Context.BIND_NOT_FOREGROUND |
| | Context.BIND_ALLOW_OOM_MANAGEMENT); |
| } |
| |
| private boolean isSignatureMatch(Signature[] signatures) { |
| if (signatures == null) return false; |
| |
| // build hashset of input to test against |
| HashSet<Signature> inputSet = new HashSet<Signature>(); |
| for (Signature s : signatures) { |
| inputSet.add(s); |
| } |
| |
| // test input against each of the signature sets |
| for (HashSet<Signature> referenceSet : mSignatureSets) { |
| if (referenceSet.equals(inputSet)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| private final PackageMonitor mPackageMonitor = new PackageMonitor() { |
| /** |
| * Called when package has been reinstalled |
| */ |
| @Override |
| public void onPackageUpdateFinished(String packageName, int uid) { |
| if (packageName.equals(mPackageName)) { |
| // package updated, make sure to rebind |
| unbind(); |
| } |
| // check the updated package in case it is better |
| bindBestPackage(packageName); |
| } |
| |
| @Override |
| public void onPackageAdded(String packageName, int uid) { |
| if (packageName.equals(mPackageName)) { |
| // package updated, make sure to rebind |
| unbind(); |
| } |
| // check the new package is case it is better |
| bindBestPackage(packageName); |
| } |
| |
| @Override |
| public void onPackageRemoved(String packageName, int uid) { |
| if (packageName.equals(mPackageName)) { |
| unbind(); |
| // the currently bound package was removed, |
| // need to search for a new package |
| bindBestPackage(null); |
| } |
| } |
| }; |
| |
| @Override |
| public void onServiceConnected(ComponentName name, IBinder binder) { |
| synchronized (mLock) { |
| String packageName = name.getPackageName(); |
| if (packageName.equals(mPackageName)) { |
| if (D) Log.d(mTag, packageName + " connected"); |
| mBinder = binder; |
| if (mHandler !=null && mNewServiceWork != null) { |
| mHandler.post(mNewServiceWork); |
| } |
| } else { |
| Log.w(mTag, "unexpected onServiceConnected: " + packageName); |
| } |
| } |
| } |
| |
| @Override |
| public void onServiceDisconnected(ComponentName name) { |
| synchronized (mLock) { |
| String packageName = name.getPackageName(); |
| if (D) Log.d(mTag, packageName + " disconnected"); |
| |
| if (packageName.equals(mPackageName)) { |
| mBinder = null; |
| } |
| } |
| } |
| |
| public String getBestPackageName() { |
| synchronized (mLock) { |
| return mPackageName; |
| } |
| } |
| |
| public int getBestVersion() { |
| synchronized (mLock) { |
| return mVersion; |
| } |
| } |
| |
| public IBinder getBinder() { |
| synchronized (mLock) { |
| return mBinder; |
| } |
| } |
| } |