| /* |
| * Copyright (C) 2016 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.wallpaperbackup; |
| |
| import static android.app.WallpaperManager.FLAG_LOCK; |
| import static android.app.WallpaperManager.FLAG_SYSTEM; |
| |
| import android.app.AppGlobals; |
| import android.app.WallpaperManager; |
| import android.app.backup.BackupAgent; |
| import android.app.backup.BackupDataInput; |
| import android.app.backup.BackupDataOutput; |
| import android.app.backup.FullBackupDataOutput; |
| import android.content.ComponentName; |
| import android.content.Context; |
| import android.content.SharedPreferences; |
| import android.content.pm.IPackageManager; |
| import android.content.pm.PackageInfo; |
| import android.graphics.Rect; |
| import android.os.Environment; |
| import android.os.FileUtils; |
| import android.os.ParcelFileDescriptor; |
| import android.os.RemoteException; |
| import android.os.UserHandle; |
| import android.util.Slog; |
| import android.util.Xml; |
| |
| import libcore.io.IoUtils; |
| |
| import org.xmlpull.v1.XmlPullParser; |
| |
| import java.io.File; |
| import java.io.FileInputStream; |
| import java.io.FileOutputStream; |
| import java.io.IOException; |
| import java.nio.charset.StandardCharsets; |
| |
| public class WallpaperBackupAgent extends BackupAgent { |
| private static final String TAG = "WallpaperBackup"; |
| private static final boolean DEBUG = false; |
| |
| // NB: must be kept in sync with WallpaperManagerService but has no |
| // compile-time visibility. |
| |
| // Target filenames within the system's wallpaper directory |
| static final String WALLPAPER = "wallpaper_orig"; |
| static final String WALLPAPER_LOCK = "wallpaper_lock_orig"; |
| static final String WALLPAPER_INFO = "wallpaper_info.xml"; |
| |
| // Names of our local-data stage files/links |
| static final String IMAGE_STAGE = "wallpaper-stage"; |
| static final String LOCK_IMAGE_STAGE = "wallpaper-lock-stage"; |
| static final String INFO_STAGE = "wallpaper-info-stage"; |
| static final String EMPTY_SENTINEL = "empty"; |
| static final String QUOTA_SENTINEL = "quota"; |
| |
| // Not-for-backup bookkeeping |
| static final String PREFS_NAME = "wbprefs.xml"; |
| static final String SYSTEM_GENERATION = "system_gen"; |
| static final String LOCK_GENERATION = "lock_gen"; |
| |
| private File mWallpaperInfo; // wallpaper metadata file |
| private File mWallpaperFile; // primary wallpaper image file |
| private File mLockWallpaperFile; // lock wallpaper image file |
| |
| // If this file exists, it means we exceeded our quota last time |
| private File mQuotaFile; |
| private boolean mQuotaExceeded; |
| |
| private WallpaperManager mWm; |
| |
| @Override |
| public void onCreate() { |
| if (DEBUG) { |
| Slog.v(TAG, "onCreate()"); |
| } |
| |
| File wallpaperDir = Environment.getUserSystemDirectory(UserHandle.USER_SYSTEM); |
| mWallpaperInfo = new File(wallpaperDir, WALLPAPER_INFO); |
| mWallpaperFile = new File(wallpaperDir, WALLPAPER); |
| mLockWallpaperFile = new File(wallpaperDir, WALLPAPER_LOCK); |
| mWm = (WallpaperManager) getSystemService(Context.WALLPAPER_SERVICE); |
| |
| mQuotaFile = new File(getFilesDir(), QUOTA_SENTINEL); |
| mQuotaExceeded = mQuotaFile.exists(); |
| if (DEBUG) { |
| Slog.v(TAG, "quota file " + mQuotaFile.getPath() + " exists=" + mQuotaExceeded); |
| } |
| } |
| |
| @Override |
| public void onFullBackup(FullBackupDataOutput data) throws IOException { |
| // To avoid data duplication and disk churn, use links as the stage. |
| final File filesDir = getFilesDir(); |
| final File infoStage = new File(filesDir, INFO_STAGE); |
| final File imageStage = new File (filesDir, IMAGE_STAGE); |
| final File lockImageStage = new File (filesDir, LOCK_IMAGE_STAGE); |
| final File empty = new File (filesDir, EMPTY_SENTINEL); |
| |
| try { |
| // We always back up this 'empty' file to ensure that the absence of |
| // storable wallpaper imagery still produces a non-empty backup data |
| // stream, otherwise it'd simply be ignored in preflight. |
| if (!empty.exists()) { |
| FileOutputStream touch = new FileOutputStream(empty); |
| touch.close(); |
| } |
| fullBackupFile(empty, data); |
| |
| SharedPreferences prefs = getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE); |
| final int lastSysGeneration = prefs.getInt(SYSTEM_GENERATION, -1); |
| final int lastLockGeneration = prefs.getInt(LOCK_GENERATION, -1); |
| |
| final int sysGeneration = |
| mWm.getWallpaperIdForUser(FLAG_SYSTEM, UserHandle.USER_SYSTEM); |
| final int lockGeneration = |
| mWm.getWallpaperIdForUser(FLAG_LOCK, UserHandle.USER_SYSTEM); |
| final boolean sysChanged = (sysGeneration != lastSysGeneration); |
| final boolean lockChanged = (lockGeneration != lastLockGeneration); |
| |
| final boolean sysEligible = mWm.isWallpaperBackupEligible(FLAG_SYSTEM); |
| final boolean lockEligible = mWm.isWallpaperBackupEligible(FLAG_LOCK); |
| |
| // There might be a latent lock wallpaper file present but unused: don't |
| // include it in the backup if that's the case. |
| ParcelFileDescriptor lockFd = mWm.getWallpaperFile(FLAG_LOCK, UserHandle.USER_SYSTEM); |
| final boolean hasLockWallpaper = (lockFd != null); |
| IoUtils.closeQuietly(lockFd); |
| |
| if (DEBUG) { |
| Slog.v(TAG, "sysGen=" + sysGeneration + " : sysChanged=" + sysChanged); |
| Slog.v(TAG, "lockGen=" + lockGeneration + " : lockChanged=" + lockChanged); |
| Slog.v(TAG, "sysEligble=" + sysEligible); |
| Slog.v(TAG, "lockEligible=" + lockEligible); |
| } |
| |
| // only back up the wallpapers if we've been told they're eligible |
| if (mWallpaperInfo.exists()) { |
| if (sysChanged || lockChanged || !infoStage.exists()) { |
| if (DEBUG) Slog.v(TAG, "New wallpaper configuration; copying"); |
| FileUtils.copyFileOrThrow(mWallpaperInfo, infoStage); |
| } |
| if (DEBUG) Slog.v(TAG, "Storing wallpaper metadata"); |
| fullBackupFile(infoStage, data); |
| } |
| if (sysEligible && mWallpaperFile.exists()) { |
| if (sysChanged || !imageStage.exists()) { |
| if (DEBUG) Slog.v(TAG, "New system wallpaper; copying"); |
| FileUtils.copyFileOrThrow(mWallpaperFile, imageStage); |
| } |
| if (DEBUG) Slog.v(TAG, "Storing system wallpaper image"); |
| fullBackupFile(imageStage, data); |
| prefs.edit().putInt(SYSTEM_GENERATION, sysGeneration).apply(); |
| } |
| |
| // Don't try to store the lock image if we overran our quota last time |
| if (lockEligible && hasLockWallpaper && mLockWallpaperFile.exists() && !mQuotaExceeded) { |
| if (lockChanged || !lockImageStage.exists()) { |
| if (DEBUG) Slog.v(TAG, "New lock wallpaper; copying"); |
| FileUtils.copyFileOrThrow(mLockWallpaperFile, lockImageStage); |
| } |
| if (DEBUG) Slog.v(TAG, "Storing lock wallpaper image"); |
| fullBackupFile(lockImageStage, data); |
| prefs.edit().putInt(LOCK_GENERATION, lockGeneration).apply(); |
| } |
| } catch (Exception e) { |
| Slog.e(TAG, "Unable to back up wallpaper", e); |
| } finally { |
| // Even if this time we had to back off on attempting to store the lock image |
| // due to exceeding the data quota, try again next time. This will alternate |
| // between "try both" and "only store the primary image" until either there |
| // is no lock image to store, or the quota is raised, or both fit under the |
| // quota. |
| mQuotaFile.delete(); |
| } |
| } |
| |
| @Override |
| public void onQuotaExceeded(long backupDataBytes, long quotaBytes) { |
| if (DEBUG) { |
| Slog.i(TAG, "Quota exceeded (" + backupDataBytes + " vs " + quotaBytes + ')'); |
| } |
| try (FileOutputStream f = new FileOutputStream(mQuotaFile)) { |
| f.write(0); |
| } catch (Exception e) { |
| Slog.w(TAG, "Unable to record quota-exceeded: " + e.getMessage()); |
| } |
| } |
| |
| // We use the default onRestoreFile() implementation that will recreate our stage files, |
| // then post-process in onRestoreFinished() to apply the new wallpaper. |
| @Override |
| public void onRestoreFinished() { |
| if (DEBUG) { |
| Slog.v(TAG, "onRestoreFinished()"); |
| } |
| final File filesDir = getFilesDir(); |
| final File infoStage = new File(filesDir, INFO_STAGE); |
| final File imageStage = new File (filesDir, IMAGE_STAGE); |
| final File lockImageStage = new File (filesDir, LOCK_IMAGE_STAGE); |
| |
| // If we restored separate lock imagery, the system wallpaper should be |
| // applied as system-only; but if there's no separate lock image, make |
| // sure to apply the restored system wallpaper as both. |
| final int sysWhich = FLAG_SYSTEM | (lockImageStage.exists() ? 0 : FLAG_LOCK); |
| |
| try { |
| // It is valid for the imagery to be absent; it means that we were not permitted |
| // to back up the original image on the source device, or there was no user-supplied |
| // wallpaper image present. |
| restoreFromStage(imageStage, infoStage, "wp", sysWhich); |
| restoreFromStage(lockImageStage, infoStage, "kwp", FLAG_LOCK); |
| |
| // And reset to the wallpaper service we should be using |
| ComponentName wpService = parseWallpaperComponent(infoStage, "wp"); |
| if (servicePackageExists(wpService)) { |
| if (DEBUG) { |
| Slog.i(TAG, "Using wallpaper service " + wpService); |
| } |
| mWm.setWallpaperComponent(wpService, UserHandle.USER_SYSTEM); |
| if (!lockImageStage.exists()) { |
| // We have a live wallpaper and no static lock image, |
| // allow live wallpaper to show "through" on lock screen. |
| mWm.clear(FLAG_LOCK); |
| } |
| } else { |
| if (DEBUG) { |
| Slog.v(TAG, "Can't use wallpaper service " + wpService); |
| } |
| } |
| } catch (Exception e) { |
| Slog.e(TAG, "Unable to restore wallpaper: " + e.getMessage()); |
| } finally { |
| if (DEBUG) { |
| Slog.v(TAG, "Restore finished; clearing backup bookkeeping"); |
| } |
| infoStage.delete(); |
| imageStage.delete(); |
| lockImageStage.delete(); |
| |
| SharedPreferences prefs = getSharedPreferences(PREFS_NAME, Context.MODE_PRIVATE); |
| prefs.edit() |
| .putInt(SYSTEM_GENERATION, -1) |
| .putInt(LOCK_GENERATION, -1) |
| .commit(); |
| } |
| } |
| |
| private void restoreFromStage(File stage, File info, String hintTag, int which) |
| throws IOException { |
| if (stage.exists()) { |
| // Parse the restored info file to find the crop hint. Note that this currently |
| // relies on a priori knowledge of the wallpaper info file schema. |
| Rect cropHint = parseCropHint(info, hintTag); |
| if (cropHint != null) { |
| Slog.i(TAG, "Got restored wallpaper; applying which=" + which); |
| if (DEBUG) { |
| Slog.v(TAG, "Restored crop hint " + cropHint); |
| } |
| try (FileInputStream in = new FileInputStream(stage)) { |
| mWm.setStream(in, cropHint.isEmpty() ? null : cropHint, true, which); |
| } finally {} // auto-closes 'in' |
| } |
| } |
| } |
| |
| private Rect parseCropHint(File wallpaperInfo, String sectionTag) { |
| Rect cropHint = new Rect(); |
| try (FileInputStream stream = new FileInputStream(wallpaperInfo)) { |
| XmlPullParser parser = Xml.newPullParser(); |
| parser.setInput(stream, StandardCharsets.UTF_8.name()); |
| |
| int type; |
| do { |
| type = parser.next(); |
| if (type == XmlPullParser.START_TAG) { |
| String tag = parser.getName(); |
| if (sectionTag.equals(tag)) { |
| cropHint.left = getAttributeInt(parser, "cropLeft", 0); |
| cropHint.top = getAttributeInt(parser, "cropTop", 0); |
| cropHint.right = getAttributeInt(parser, "cropRight", 0); |
| cropHint.bottom = getAttributeInt(parser, "cropBottom", 0); |
| } |
| } |
| } while (type != XmlPullParser.END_DOCUMENT); |
| } catch (Exception e) { |
| // Whoops; can't process the info file at all. Report failure. |
| Slog.w(TAG, "Failed to parse restored crop: " + e.getMessage()); |
| return null; |
| } |
| |
| return cropHint; |
| } |
| |
| private ComponentName parseWallpaperComponent(File wallpaperInfo, String sectionTag) { |
| ComponentName name = null; |
| try (FileInputStream stream = new FileInputStream(wallpaperInfo)) { |
| final XmlPullParser parser = Xml.newPullParser(); |
| parser.setInput(stream, StandardCharsets.UTF_8.name()); |
| |
| int type; |
| do { |
| type = parser.next(); |
| if (type == XmlPullParser.START_TAG) { |
| String tag = parser.getName(); |
| if (sectionTag.equals(tag)) { |
| final String parsedName = parser.getAttributeValue(null, "component"); |
| name = (parsedName != null) |
| ? ComponentName.unflattenFromString(parsedName) |
| : null; |
| break; |
| } |
| } |
| } while (type != XmlPullParser.END_DOCUMENT); |
| } catch (Exception e) { |
| // Whoops; can't process the info file at all. Report failure. |
| Slog.w(TAG, "Failed to parse restored component: " + e.getMessage()); |
| return null; |
| } |
| return name; |
| } |
| |
| private int getAttributeInt(XmlPullParser parser, String name, int defValue) { |
| final String value = parser.getAttributeValue(null, name); |
| return (value == null) ? defValue : Integer.parseInt(value); |
| } |
| |
| private boolean servicePackageExists(ComponentName comp) { |
| try { |
| if (comp != null) { |
| final IPackageManager pm = AppGlobals.getPackageManager(); |
| final PackageInfo info = pm.getPackageInfo(comp.getPackageName(), |
| 0, UserHandle.USER_SYSTEM); |
| return (info != null); |
| } |
| } catch (RemoteException e) { |
| Slog.e(TAG, "Unable to contact package manager"); |
| } |
| return false; |
| } |
| |
| // |
| // Key/value API: abstract, therefore required; but not used |
| // |
| |
| @Override |
| public void onBackup(ParcelFileDescriptor oldState, BackupDataOutput data, |
| ParcelFileDescriptor newState) throws IOException { |
| // Intentionally blank |
| } |
| |
| @Override |
| public void onRestore(BackupDataInput data, int appVersionCode, ParcelFileDescriptor newState) |
| throws IOException { |
| // Intentionally blank |
| } |
| } |