SystemBackupAgent.java revision e9fd1fa31ad6f62d1eb6f32cdcdab50349f246eb 
1/*
2 * Copyright (C) 2009 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.server.backup;
18
19import android.app.IWallpaperManager;
20import android.app.backup.BackupDataInput;
21import android.app.backup.BackupDataOutput;
22import android.app.backup.BackupAgentHelper;
23import android.app.backup.FullBackup;
24import android.app.backup.FullBackupDataOutput;
25import android.app.backup.WallpaperBackupHelper;
26import android.content.Context;
27import android.os.Environment;
28import android.os.ParcelFileDescriptor;
29import android.os.RemoteException;
30import android.os.ServiceManager;
31import android.os.UserHandle;
32import android.util.Slog;
33
34import java.io.File;
35import java.io.IOException;
36
37/**
38 * Backup agent for various system-managed data, currently just the system wallpaper
39 */
40public class SystemBackupAgent extends BackupAgentHelper {
41    private static final String TAG = "SystemBackupAgent";
42
43    // Names of the helper tags within the dataset.  Changing one of these names will
44    // break the ability to restore from datasets that predate the change.
45    private static final String WALLPAPER_HELPER = "wallpaper";
46    private static final String SYNC_SETTINGS_HELPER = "account_sync_settings";
47    private static final String PREFERRED_HELPER = "preferred_activities";
48    private static final String NOTIFICATION_HELPER = "notifications";
49    private static final String PERMISSION_HELPER = "permissions";
50
51    // These paths must match what the WallpaperManagerService uses.  The leaf *_FILENAME
52    // are also used in the full-backup file format, so must not change unless steps are
53    // taken to support the legacy backed-up datasets.
54    private static final String WALLPAPER_IMAGE_FILENAME = "wallpaper";
55    private static final String WALLPAPER_INFO_FILENAME = "wallpaper_info.xml";
56
57    // TODO: Will need to change if backing up non-primary user's wallpaper
58    // TODO: http://b/22388012
59    private static final String WALLPAPER_IMAGE_DIR =
60            Environment.getUserSystemDirectory(UserHandle.USER_SYSTEM).getAbsolutePath();
61    private static final String WALLPAPER_IMAGE = WallpaperBackupHelper.WALLPAPER_IMAGE;
62
63    // TODO: Will need to change if backing up non-primary user's wallpaper
64    // TODO: http://b/22388012
65    private static final String WALLPAPER_INFO_DIR =
66            Environment.getUserSystemDirectory(UserHandle.USER_SYSTEM).getAbsolutePath();
67    private static final String WALLPAPER_INFO = WallpaperBackupHelper.WALLPAPER_INFO;
68    // Use old keys to keep legacy data compatibility and avoid writing two wallpapers
69    private static final String WALLPAPER_IMAGE_KEY = WallpaperBackupHelper.WALLPAPER_IMAGE_KEY;
70    private static final String WALLPAPER_INFO_KEY = WallpaperBackupHelper.WALLPAPER_INFO_KEY;
71
72    @Override
73    public void onBackup(ParcelFileDescriptor oldState, BackupDataOutput data,
74            ParcelFileDescriptor newState) throws IOException {
75        // We only back up the data under the current "wallpaper" schema with metadata
76        IWallpaperManager wallpaper = (IWallpaperManager)ServiceManager.getService(
77                Context.WALLPAPER_SERVICE);
78        String[] files = new String[] { WALLPAPER_IMAGE, WALLPAPER_INFO };
79        String[] keys = new String[] { WALLPAPER_IMAGE_KEY, WALLPAPER_INFO_KEY };
80        if (wallpaper != null) {
81            try {
82                final String wallpaperName = wallpaper.getName();
83                if (wallpaperName != null && wallpaperName.length() > 0) {
84                    // When the wallpaper has a name, back up the info by itself.
85                    // TODO: Don't rely on the innards of the service object like this!
86                    // TODO: Send a delete for any stored wallpaper image in this case?
87                    files = new String[] { WALLPAPER_INFO };
88                    keys = new String[] { WALLPAPER_INFO_KEY };
89                }
90            } catch (RemoteException re) {
91                Slog.e(TAG, "Couldn't get wallpaper name\n" + re);
92            }
93        }
94        addHelper(WALLPAPER_HELPER, new WallpaperBackupHelper(this, files, keys));
95        addHelper(SYNC_SETTINGS_HELPER, new AccountSyncSettingsBackupHelper(this));
96        addHelper(PREFERRED_HELPER, new PreferredActivityBackupHelper());
97        addHelper(NOTIFICATION_HELPER, new NotificationBackupHelper(this));
98        addHelper(PERMISSION_HELPER, new PermissionBackupHelper());
99
100        super.onBackup(oldState, data, newState);
101    }
102
103    @Override
104    public void onFullBackup(FullBackupDataOutput data) throws IOException {
105        // At present we back up only the wallpaper
106        fullWallpaperBackup(data);
107    }
108
109    private void fullWallpaperBackup(FullBackupDataOutput output) {
110        // Back up the data files directly.  We do them in this specific order --
111        // info file followed by image -- because then we need take no special
112        // steps during restore; the restore will happen properly when the individual
113        // files are restored piecemeal.
114        FullBackup.backupToTar(getPackageName(), FullBackup.ROOT_TREE_TOKEN, null,
115                WALLPAPER_INFO_DIR, WALLPAPER_INFO, output);
116        FullBackup.backupToTar(getPackageName(), FullBackup.ROOT_TREE_TOKEN, null,
117                WALLPAPER_IMAGE_DIR, WALLPAPER_IMAGE, output);
118    }
119
120    @Override
121    public void onRestore(BackupDataInput data, int appVersionCode, ParcelFileDescriptor newState)
122            throws IOException {
123        // On restore, we also support a previous data schema "system_files"
124        addHelper(WALLPAPER_HELPER, new WallpaperBackupHelper(this,
125                new String[] { WALLPAPER_IMAGE, WALLPAPER_INFO },
126                new String[] { WALLPAPER_IMAGE_KEY, WALLPAPER_INFO_KEY} ));
127        addHelper("system_files", new WallpaperBackupHelper(this,
128                new String[] { WALLPAPER_IMAGE },
129                new String[] { WALLPAPER_IMAGE_KEY} ));
130        addHelper(SYNC_SETTINGS_HELPER, new AccountSyncSettingsBackupHelper(this));
131        addHelper(PREFERRED_HELPER, new PreferredActivityBackupHelper());
132        addHelper(NOTIFICATION_HELPER, new NotificationBackupHelper(this));
133        addHelper(PERMISSION_HELPER, new PermissionBackupHelper());
134
135        try {
136            super.onRestore(data, appVersionCode, newState);
137
138            IWallpaperManager wallpaper = (IWallpaperManager) ServiceManager.getService(
139                    Context.WALLPAPER_SERVICE);
140            if (wallpaper != null) {
141                try {
142                    wallpaper.settingsRestored();
143                } catch (RemoteException re) {
144                    Slog.e(TAG, "Couldn't restore settings\n" + re);
145                }
146            }
147        } catch (IOException ex) {
148            // If there was a failure, delete everything for the wallpaper, this is too aggressive,
149            // but this is hopefully a rare failure.
150            Slog.d(TAG, "restore failed", ex);
151            (new File(WALLPAPER_IMAGE)).delete();
152            (new File(WALLPAPER_INFO)).delete();
153        }
154    }
155
156    @Override
157    public void onRestoreFile(ParcelFileDescriptor data, long size,
158            int type, String domain, String path, long mode, long mtime)
159            throws IOException {
160        Slog.i(TAG, "Restoring file domain=" + domain + " path=" + path);
161
162        // Bits to indicate postprocessing we may need to perform
163        boolean restoredWallpaper = false;
164
165        File outFile = null;
166        // Various domain+files we understand a priori
167        if (domain.equals(FullBackup.ROOT_TREE_TOKEN)) {
168            if (path.equals(WALLPAPER_INFO_FILENAME)) {
169                outFile = new File(WALLPAPER_INFO);
170                restoredWallpaper = true;
171            } else if (path.equals(WALLPAPER_IMAGE_FILENAME)) {
172                outFile = new File(WALLPAPER_IMAGE);
173                restoredWallpaper = true;
174            }
175        }
176
177        try {
178            if (outFile == null) {
179                Slog.w(TAG, "Skipping unrecognized system file: [ " + domain + " : " + path + " ]");
180            }
181            FullBackup.restoreFile(data, size, type, mode, mtime, outFile);
182
183            if (restoredWallpaper) {
184                IWallpaperManager wallpaper =
185                        (IWallpaperManager)ServiceManager.getService(
186                        Context.WALLPAPER_SERVICE);
187                if (wallpaper != null) {
188                    try {
189                        wallpaper.settingsRestored();
190                    } catch (RemoteException re) {
191                        Slog.e(TAG, "Couldn't restore settings\n" + re);
192                    }
193                }
194            }
195        } catch (IOException e) {
196            if (restoredWallpaper) {
197                // Make sure we wind up in a good state
198                (new File(WALLPAPER_IMAGE)).delete();
199                (new File(WALLPAPER_INFO)).delete();
200            }
201        }
202    }
203}
204