SystemBackupAgent.java revision a6533256ac1de9d0860688ca743aa7a2468470cc 
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
19
20import android.app.ActivityManagerNative;
21import android.app.IWallpaperManager;
22import android.app.backup.BackupDataInput;
23import android.app.backup.BackupDataOutput;
24import android.app.backup.BackupAgentHelper;
25import android.app.backup.FullBackup;
26import android.app.backup.FullBackupDataOutput;
27import android.app.backup.RecentsBackupHelper;
28import android.app.backup.WallpaperBackupHelper;
29import android.content.Context;
30import android.os.Environment;
31import android.os.ParcelFileDescriptor;
32import android.os.RemoteException;
33import android.os.ServiceManager;
34import android.os.UserHandle;
35import android.util.Slog;
36
37import java.io.File;
38import java.io.IOException;
39
40/**
41 * Backup agent for various system-managed data, currently just the system wallpaper
42 */
43public class SystemBackupAgent extends BackupAgentHelper {
44    private static final String TAG = "SystemBackupAgent";
45
46    // These paths must match what the WallpaperManagerService uses.  The leaf *_FILENAME
47    // are also used in the full-backup file format, so must not change unless steps are
48    // taken to support the legacy backed-up datasets.
49    private static final String WALLPAPER_IMAGE_FILENAME = "wallpaper";
50    private static final String WALLPAPER_INFO_FILENAME = "wallpaper_info.xml";
51
52    // TODO: Will need to change if backing up non-primary user's wallpaper
53    private static final String WALLPAPER_IMAGE_DIR =
54            Environment.getUserSystemDirectory(UserHandle.USER_OWNER).getAbsolutePath();
55    private static final String WALLPAPER_IMAGE = WallpaperBackupHelper.WALLPAPER_IMAGE;
56
57    // TODO: Will need to change if backing up non-primary user's wallpaper
58    private static final String WALLPAPER_INFO_DIR =
59            Environment.getUserSystemDirectory(UserHandle.USER_OWNER).getAbsolutePath();
60    private static final String WALLPAPER_INFO = WallpaperBackupHelper.WALLPAPER_INFO;
61    // Use old keys to keep legacy data compatibility and avoid writing two wallpapers
62    private static final String WALLPAPER_IMAGE_KEY = WallpaperBackupHelper.WALLPAPER_IMAGE_KEY;
63    private static final String WALLPAPER_INFO_KEY = WallpaperBackupHelper.WALLPAPER_INFO_KEY;
64
65    @Override
66    public void onBackup(ParcelFileDescriptor oldState, BackupDataOutput data,
67            ParcelFileDescriptor newState) throws IOException {
68        // We only back up the data under the current "wallpaper" schema with metadata
69        IWallpaperManager wallpaper = (IWallpaperManager)ServiceManager.getService(
70                Context.WALLPAPER_SERVICE);
71        String[] files = new String[] { WALLPAPER_IMAGE, WALLPAPER_INFO };
72        String[] keys = new String[] { WALLPAPER_IMAGE_KEY, WALLPAPER_INFO_KEY };
73        if (wallpaper != null) {
74            try {
75                final String wallpaperName = wallpaper.getName();
76                if (wallpaperName != null && wallpaperName.length() > 0) {
77                    // When the wallpaper has a name, back up the info by itself.
78                    // TODO: Don't rely on the innards of the service object like this!
79                    // TODO: Send a delete for any stored wallpaper image in this case?
80                    files = new String[] { WALLPAPER_INFO };
81                    keys = new String[] { WALLPAPER_INFO_KEY };
82                }
83            } catch (RemoteException re) {
84                Slog.e(TAG, "Couldn't get wallpaper name\n" + re);
85            }
86        }
87        addHelper("wallpaper", new WallpaperBackupHelper(SystemBackupAgent.this, files, keys));
88        addHelper("recents", new RecentsBackupHelper(SystemBackupAgent.this));
89        addHelper("account_sync_settings",
90                new AccountSyncSettingsBackupHelper(SystemBackupAgent.this));
91
92        super.onBackup(oldState, data, newState);
93    }
94
95    @Override
96    public void onFullBackup(FullBackupDataOutput data) throws IOException {
97        // At present we back up only the wallpaper
98        fullWallpaperBackup(data);
99    }
100
101    private void fullWallpaperBackup(FullBackupDataOutput output) {
102        // Back up the data files directly.  We do them in this specific order --
103        // info file followed by image -- because then we need take no special
104        // steps during restore; the restore will happen properly when the individual
105        // files are restored piecemeal.
106        FullBackup.backupToTar(getPackageName(), FullBackup.ROOT_TREE_TOKEN, null,
107                WALLPAPER_INFO_DIR, WALLPAPER_INFO, output.getData());
108        FullBackup.backupToTar(getPackageName(), FullBackup.ROOT_TREE_TOKEN, null,
109                WALLPAPER_IMAGE_DIR, WALLPAPER_IMAGE, output.getData());
110    }
111
112    @Override
113    public void onRestore(BackupDataInput data, int appVersionCode, ParcelFileDescriptor newState)
114            throws IOException {
115        // On restore, we also support a previous data schema "system_files"
116        addHelper("wallpaper", new WallpaperBackupHelper(SystemBackupAgent.this,
117                new String[] { WALLPAPER_IMAGE, WALLPAPER_INFO },
118                new String[] { WALLPAPER_IMAGE_KEY, WALLPAPER_INFO_KEY} ));
119        addHelper("system_files", new WallpaperBackupHelper(SystemBackupAgent.this,
120                new String[] { WALLPAPER_IMAGE },
121                new String[] { WALLPAPER_IMAGE_KEY} ));
122        addHelper("recents", new RecentsBackupHelper(SystemBackupAgent.this));
123        addHelper("account_sync_settings",
124                new AccountSyncSettingsBackupHelper(SystemBackupAgent.this));
125
126        try {
127            super.onRestore(data, appVersionCode, newState);
128
129            IWallpaperManager wallpaper = (IWallpaperManager) ServiceManager.getService(
130                    Context.WALLPAPER_SERVICE);
131            if (wallpaper != null) {
132                try {
133                    wallpaper.settingsRestored();
134                } catch (RemoteException re) {
135                    Slog.e(TAG, "Couldn't restore settings\n" + re);
136                }
137            }
138        } catch (IOException ex) {
139            // If there was a failure, delete everything for the wallpaper, this is too aggressive,
140            // but this is hopefully a rare failure.
141            Slog.d(TAG, "restore failed", ex);
142            (new File(WALLPAPER_IMAGE)).delete();
143            (new File(WALLPAPER_INFO)).delete();
144        }
145    }
146
147    @Override
148    public void onRestoreFile(ParcelFileDescriptor data, long size,
149            int type, String domain, String path, long mode, long mtime)
150            throws IOException {
151        Slog.i(TAG, "Restoring file domain=" + domain + " path=" + path);
152
153        // Bits to indicate postprocessing we may need to perform
154        boolean restoredWallpaper = false;
155
156        File outFile = null;
157        // Various domain+files we understand a priori
158        if (domain.equals(FullBackup.ROOT_TREE_TOKEN)) {
159            if (path.equals(WALLPAPER_INFO_FILENAME)) {
160                outFile = new File(WALLPAPER_INFO);
161                restoredWallpaper = true;
162            } else if (path.equals(WALLPAPER_IMAGE_FILENAME)) {
163                outFile = new File(WALLPAPER_IMAGE);
164                restoredWallpaper = true;
165            }
166        }
167
168        try {
169            if (outFile == null) {
170                Slog.w(TAG, "Skipping unrecognized system file: [ " + domain + " : " + path + " ]");
171            }
172            FullBackup.restoreFile(data, size, type, mode, mtime, outFile);
173
174            if (restoredWallpaper) {
175                IWallpaperManager wallpaper =
176                        (IWallpaperManager)ServiceManager.getService(
177                        Context.WALLPAPER_SERVICE);
178                if (wallpaper != null) {
179                    try {
180                        wallpaper.settingsRestored();
181                    } catch (RemoteException re) {
182                        Slog.e(TAG, "Couldn't restore settings\n" + re);
183                    }
184                }
185            }
186        } catch (IOException e) {
187            if (restoredWallpaper) {
188                // Make sure we wind up in a good state
189                (new File(WALLPAPER_IMAGE)).delete();
190                (new File(WALLPAPER_INFO)).delete();
191            }
192        }
193    }
194
195    @Override
196    public void onRestoreFinished() {
197        try {
198            ActivityManagerNative.getDefault().systemBackupRestored();
199        } catch (RemoteException e) {
200            // Not possible since this code is running in the system process.
201        }
202    }
203}
204