SystemBackupAgent.java revision 4cfe29bdf2ee14e8316d45cfc23e4548319b3ab9 
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
50    // These paths must match what the WallpaperManagerService uses.  The leaf *_FILENAME
51    // are also used in the full-backup file format, so must not change unless steps are
52    // taken to support the legacy backed-up datasets.
53    private static final String WALLPAPER_IMAGE_FILENAME = "wallpaper";
54    private static final String WALLPAPER_INFO_FILENAME = "wallpaper_info.xml";
55
56    // TODO: Will need to change if backing up non-primary user's wallpaper
57    // TODO: http://b/22388012
58    private static final String WALLPAPER_IMAGE_DIR =
59            Environment.getUserSystemDirectory(UserHandle.USER_SYSTEM).getAbsolutePath();
60    private static final String WALLPAPER_IMAGE = WallpaperBackupHelper.WALLPAPER_IMAGE;
61
62    // TODO: Will need to change if backing up non-primary user's wallpaper
63    // TODO: http://b/22388012
64    private static final String WALLPAPER_INFO_DIR =
65            Environment.getUserSystemDirectory(UserHandle.USER_SYSTEM).getAbsolutePath();
66    private static final String WALLPAPER_INFO = WallpaperBackupHelper.WALLPAPER_INFO;
67    // Use old keys to keep legacy data compatibility and avoid writing two wallpapers
68    private static final String WALLPAPER_IMAGE_KEY = WallpaperBackupHelper.WALLPAPER_IMAGE_KEY;
69    private static final String WALLPAPER_INFO_KEY = WallpaperBackupHelper.WALLPAPER_INFO_KEY;
70
71    @Override
72    public void onBackup(ParcelFileDescriptor oldState, BackupDataOutput data,
73            ParcelFileDescriptor newState) throws IOException {
74        // We only back up the data under the current "wallpaper" schema with metadata
75        IWallpaperManager wallpaper = (IWallpaperManager)ServiceManager.getService(
76                Context.WALLPAPER_SERVICE);
77        String[] files = new String[] { WALLPAPER_IMAGE, WALLPAPER_INFO };
78        String[] keys = new String[] { WALLPAPER_IMAGE_KEY, WALLPAPER_INFO_KEY };
79        if (wallpaper != null) {
80            try {
81                final String wallpaperName = wallpaper.getName();
82                if (wallpaperName != null && wallpaperName.length() > 0) {
83                    // When the wallpaper has a name, back up the info by itself.
84                    // TODO: Don't rely on the innards of the service object like this!
85                    // TODO: Send a delete for any stored wallpaper image in this case?
86                    files = new String[] { WALLPAPER_INFO };
87                    keys = new String[] { WALLPAPER_INFO_KEY };
88                }
89            } catch (RemoteException re) {
90                Slog.e(TAG, "Couldn't get wallpaper name\n" + re);
91            }
92        }
93        addHelper(WALLPAPER_HELPER, new WallpaperBackupHelper(this, files, keys));
94        addHelper(SYNC_SETTINGS_HELPER, new AccountSyncSettingsBackupHelper(this));
95        addHelper(PREFERRED_HELPER, new PreferredActivityBackupHelper());
96        addHelper(NOTIFICATION_HELPER, new NotificationBackupHelper(this));
97
98        super.onBackup(oldState, data, newState);
99    }
100
101    @Override
102    public void onFullBackup(FullBackupDataOutput data) throws IOException {
103        // At present we back up only the wallpaper
104        fullWallpaperBackup(data);
105    }
106
107    private void fullWallpaperBackup(FullBackupDataOutput output) {
108        // Back up the data files directly.  We do them in this specific order --
109        // info file followed by image -- because then we need take no special
110        // steps during restore; the restore will happen properly when the individual
111        // files are restored piecemeal.
112        FullBackup.backupToTar(getPackageName(), FullBackup.ROOT_TREE_TOKEN, null,
113                WALLPAPER_INFO_DIR, WALLPAPER_INFO, output);
114        FullBackup.backupToTar(getPackageName(), FullBackup.ROOT_TREE_TOKEN, null,
115                WALLPAPER_IMAGE_DIR, WALLPAPER_IMAGE, output);
116    }
117
118    @Override
119    public void onRestore(BackupDataInput data, int appVersionCode, ParcelFileDescriptor newState)
120            throws IOException {
121        // On restore, we also support a previous data schema "system_files"
122        addHelper(WALLPAPER_HELPER, new WallpaperBackupHelper(this,
123                new String[] { WALLPAPER_IMAGE, WALLPAPER_INFO },
124                new String[] { WALLPAPER_IMAGE_KEY, WALLPAPER_INFO_KEY} ));
125        addHelper("system_files", new WallpaperBackupHelper(this,
126                new String[] { WALLPAPER_IMAGE },
127                new String[] { WALLPAPER_IMAGE_KEY} ));
128        addHelper(SYNC_SETTINGS_HELPER, new AccountSyncSettingsBackupHelper(this));
129        addHelper(PREFERRED_HELPER, new PreferredActivityBackupHelper());
130        addHelper(NOTIFICATION_HELPER, new NotificationBackupHelper(this));
131
132        try {
133            super.onRestore(data, appVersionCode, newState);
134
135            IWallpaperManager wallpaper = (IWallpaperManager) ServiceManager.getService(
136                    Context.WALLPAPER_SERVICE);
137            if (wallpaper != null) {
138                try {
139                    wallpaper.settingsRestored();
140                } catch (RemoteException re) {
141                    Slog.e(TAG, "Couldn't restore settings\n" + re);
142                }
143            }
144        } catch (IOException ex) {
145            // If there was a failure, delete everything for the wallpaper, this is too aggressive,
146            // but this is hopefully a rare failure.
147            Slog.d(TAG, "restore failed", ex);
148            (new File(WALLPAPER_IMAGE)).delete();
149            (new File(WALLPAPER_INFO)).delete();
150        }
151    }
152
153    @Override
154    public void onRestoreFile(ParcelFileDescriptor data, long size,
155            int type, String domain, String path, long mode, long mtime)
156            throws IOException {
157        Slog.i(TAG, "Restoring file domain=" + domain + " path=" + path);
158
159        // Bits to indicate postprocessing we may need to perform
160        boolean restoredWallpaper = false;
161
162        File outFile = null;
163        // Various domain+files we understand a priori
164        if (domain.equals(FullBackup.ROOT_TREE_TOKEN)) {
165            if (path.equals(WALLPAPER_INFO_FILENAME)) {
166                outFile = new File(WALLPAPER_INFO);
167                restoredWallpaper = true;
168            } else if (path.equals(WALLPAPER_IMAGE_FILENAME)) {
169                outFile = new File(WALLPAPER_IMAGE);
170                restoredWallpaper = true;
171            }
172        }
173
174        try {
175            if (outFile == null) {
176                Slog.w(TAG, "Skipping unrecognized system file: [ " + domain + " : " + path + " ]");
177            }
178            FullBackup.restoreFile(data, size, type, mode, mtime, outFile);
179
180            if (restoredWallpaper) {
181                IWallpaperManager wallpaper =
182                        (IWallpaperManager)ServiceManager.getService(
183                        Context.WALLPAPER_SERVICE);
184                if (wallpaper != null) {
185                    try {
186                        wallpaper.settingsRestored();
187                    } catch (RemoteException re) {
188                        Slog.e(TAG, "Couldn't restore settings\n" + re);
189                    }
190                }
191            }
192        } catch (IOException e) {
193            if (restoredWallpaper) {
194                // Make sure we wind up in a good state
195                (new File(WALLPAPER_IMAGE)).delete();
196                (new File(WALLPAPER_INFO)).delete();
197            }
198        }
199    }
200}
201