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 android.app.backup;
18
19import android.content.Context;
20import android.os.ParcelFileDescriptor;
21import android.util.Log;
22
23import java.io.File;
24import java.io.FileDescriptor;
25
26/**
27 * Base class for the {@link android.app.backup.FileBackupHelper} implementation.
28 */
29class FileBackupHelperBase {
30    private static final String TAG = "FileBackupHelperBase";
31
32    long mPtr;
33    Context mContext;
34    boolean mExceptionLogged;
35
36    FileBackupHelperBase(Context context) {
37        mPtr = ctor();
38        mContext = context;
39    }
40
41    protected void finalize() throws Throwable {
42        try {
43            dtor(mPtr);
44        } finally {
45            super.finalize();
46        }
47    }
48
49    /**
50     * Check the parameters so the native code doesn't have to throw all the exceptions
51     * since it's easier to do that from Java.
52     */
53    static void performBackup_checked(ParcelFileDescriptor oldState, BackupDataOutput data,
54            ParcelFileDescriptor newState, String[] files, String[] keys) {
55        if (files.length == 0) {
56            return;
57        }
58        // files must be all absolute paths
59        for (String f: files) {
60            if (f.charAt(0) != '/') {
61                throw new RuntimeException("files must have all absolute paths: " + f);
62            }
63        }
64        // the length of files and keys must be the same
65        if (files.length != keys.length) {
66            throw new RuntimeException("files.length=" + files.length
67                    + " keys.length=" + keys.length);
68        }
69        // oldStateFd can be null
70        FileDescriptor oldStateFd = oldState != null ? oldState.getFileDescriptor() : null;
71        FileDescriptor newStateFd = newState.getFileDescriptor();
72        if (newStateFd == null) {
73            throw new NullPointerException();
74        }
75
76        int err = performBackup_native(oldStateFd, data.mBackupWriter, newStateFd, files, keys);
77
78        if (err != 0) {
79            // TODO: more here
80            throw new RuntimeException("Backup failed 0x" + Integer.toHexString(err));
81        }
82    }
83
84    boolean writeFile(File f, BackupDataInputStream in) {
85        int result = -1;
86
87        // Create the enclosing directory.
88        File parent = f.getParentFile();
89        parent.mkdirs();
90
91        result = writeFile_native(mPtr, f.getAbsolutePath(), in.mData.mBackupReader);
92        if (result != 0) {
93            // Bail on this entity.  Only log one failure per helper object.
94            if (!mExceptionLogged) {
95                Log.e(TAG, "Failed restoring file '" + f + "' for app '"
96                        + mContext.getPackageName() + "\' result=0x"
97                        + Integer.toHexString(result));
98                mExceptionLogged = true;
99            }
100        }
101        return (result == 0);
102    }
103
104    public void writeNewStateDescription(ParcelFileDescriptor fd) {
105        int result = writeSnapshot_native(mPtr, fd.getFileDescriptor());
106        // TODO: Do something with the error.
107    }
108
109    boolean isKeyInList(String key, String[] list) {
110        for (String s: list) {
111            if (s.equals(key)) {
112                return true;
113            }
114        }
115        return false;
116    }
117
118    private static native long ctor();
119    private static native void dtor(long ptr);
120
121    native private static int performBackup_native(FileDescriptor oldState,
122            long data, FileDescriptor newState, String[] files, String[] keys);
123    private static native int writeFile_native(long ptr, String filename, long backupReader);
124    private static native int writeSnapshot_native(long ptr, FileDescriptor fd);
125}
126
127
128