1 /*
2  * Copyright 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 
17 package android.app;
18 
19 import android.app.backup.IBackupManager;
20 import android.os.ParcelFileDescriptor;
21 
22 /**
23  * Interface presented by applications being asked to participate in the
24  * backup & restore mechanism.  End user code will not typically implement
25  * this interface directly; they subclass BackupAgent instead.
26  *
27  * {@hide}
28  */
29 oneway interface IBackupAgent {
30     /**
31      * Request that the app perform an incremental backup.
32      *
33      * @param oldState Read-only file containing the description blob of the
34      *        app's data state as of the last backup operation's completion.
35      *        This file is empty or invalid when a full backup is being
36      *        requested.
37      *
38      * @param data Read-write file, empty when onBackup() is called, that
39      *        is the data destination for this backup pass's incrementals.
40      *
41      * @param newState Read-write file, empty when onBackup() is called,
42      *        where the new state blob is to be recorded.
43      *
44      * @param quota Quota reported by the transport for this backup operation (in bytes).
45      *
46      * @param token Opaque token identifying this transaction.  This must
47      *        be echoed back to the backup service binder once the new
48      *        data has been written to the data and newState files.
49      *
50      * @param callbackBinder Binder on which to indicate operation completion,
51      *        passed here as a convenience to the agent.
52      */
doBackup(in ParcelFileDescriptor oldState, in ParcelFileDescriptor data, in ParcelFileDescriptor newState, long quotaBytes, int token, IBackupManager callbackBinder)53     void doBackup(in ParcelFileDescriptor oldState,
54             in ParcelFileDescriptor data,
55             in ParcelFileDescriptor newState,
56             long quotaBytes, int token, IBackupManager callbackBinder);
57 
58     /**
59      * Restore an entire data snapshot to the application.
60      *
61      * @param data Read-only file containing the full data snapshot of the
62      *        app's backup.  This is to be a <i>replacement</i> of the app's
63      *        current data, not to be merged into it.
64      *
65      * @param appVersionCode The android:versionCode attribute of the application
66      *        that created this data set.  This can help the agent distinguish among
67      *        various historical backup content possibilities.
68      *
69      * @param newState Read-write file, empty when onRestore() is called,
70      *        that is to be written with the state description that holds after
71      *        the restore has been completed.
72      *
73      * @param token Opaque token identifying this transaction.  This must
74      *        be echoed back to the backup service binder once the agent is
75      *        finished restoring the application based on the restore data
76      *        contents.
77      *
78      * @param callbackBinder Binder on which to indicate operation completion,
79      *        passed here as a convenience to the agent.
80      */
doRestore(in ParcelFileDescriptor data, int appVersionCode, in ParcelFileDescriptor newState, int token, IBackupManager callbackBinder)81     void doRestore(in ParcelFileDescriptor data,
82             int appVersionCode, in ParcelFileDescriptor newState,
83             int token, IBackupManager callbackBinder);
84 
85     /**
86      * Perform a "full" backup to the given file descriptor.  The output file is presumed
87      * to be a socket or other non-seekable, write-only data sink.  When this method is
88      * called, the app should write all of its files to the output.
89      *
90      * @param data Write-only file to receive the backed-up file content stream.
91      *        The data must be formatted correctly for the resulting archive to be
92      *        legitimate, so that will be tightly controlled by the available API.
93      *
94      * @param quota Quota reported by the transport for this backup operation (in bytes).
95      *
96      * @param token Opaque token identifying this transaction.  This must
97      *        be echoed back to the backup service binder once the agent is
98      *        finished restoring the application based on the restore data
99      *        contents.
100      *
101      * @param callbackBinder Binder on which to indicate operation completion,
102      *        passed here as a convenience to the agent.
103      */
doFullBackup(in ParcelFileDescriptor data, long quotaBytes, int token, IBackupManager callbackBinder)104     void doFullBackup(in ParcelFileDescriptor data, long quotaBytes, int token, IBackupManager callbackBinder);
105 
106     /**
107      * Estimate how much data a full backup will deliver
108      */
doMeasureFullBackup(long quotaBytes, int token, IBackupManager callbackBinder)109     void doMeasureFullBackup(long quotaBytes, int token, IBackupManager callbackBinder);
110 
111     /**
112      * Tells the application agent that the backup data size exceeded current transport quota.
113      * Later calls to {@link #onBackup(ParcelFileDescriptor, BackupDataOutput, ParcelFileDescriptor)}
114      * and {@link #onFullBackup(FullBackupDataOutput)} could use this information
115      * to reduce backup size under the limit.
116      * However, the quota can change, so do not assume that the value passed in here is absolute,
117      * similarly all subsequent backups should not be restricted to this size.
118      * This callback will be invoked before data has been put onto the wire in a preflight check,
119      * so it is relatively inexpensive to hit your quota.
120      * Apps that hit quota repeatedly without dealing with it can be subject to having their backup
121      * schedule reduced.
122      * The {@code quotaBytes} is a loose guideline b/c of metadata added by the backupmanager
123      * so apps should be more aggressive in trimming their backup set.
124      *
125      * @param backupDataBytes Expected or already processed amount of data.
126      *                        Could be less than total backup size if backup process was interrupted
127      *                        before finish of processing all backup data.
128      * @param quotaBytes Current amount of backup data that is allowed for the app.
129      */
doQuotaExceeded(long backupDataBytes, long quotaBytes)130     void doQuotaExceeded(long backupDataBytes, long quotaBytes);
131 
132     /**
133      * Restore a single "file" to the application.  The file was typically obtained from
134      * a full-backup dataset.  The agent reads 'size' bytes of file content
135      * from the provided file descriptor.
136      *
137      * @param data Read-only pipe delivering the file content itself.
138      *
139      * @param size Size of the file being restored.
140      * @param type Type of file system entity, e.g. FullBackup.TYPE_DIRECTORY.
141      * @param domain Name of the file's semantic domain to which the 'path' argument is a
142      *        relative path.  e.g. FullBackup.DATABASE_TREE_TOKEN.
143      * @param path Relative path of the file within its semantic domain.
144      * @param mode Access mode of the file system entity, e.g. 0660.
145      * @param mtime Last modification time of the file system entity.
146      * @param token Opaque token identifying this transaction.  This must
147      *        be echoed back to the backup service binder once the agent is
148      *        finished restoring the application based on the restore data
149      *        contents.
150      * @param callbackBinder Binder on which to indicate operation completion,
151      *        passed here as a convenience to the agent.
152      */
doRestoreFile(in ParcelFileDescriptor data, long size, int type, String domain, String path, long mode, long mtime, int token, IBackupManager callbackBinder)153     void doRestoreFile(in ParcelFileDescriptor data, long size,
154             int type, String domain, String path, long mode, long mtime,
155             int token, IBackupManager callbackBinder);
156 
157     /**
158      * Provide the app with a canonical "all data has been delivered" end-of-restore
159      * callback so that it can do any postprocessing of the restored data that might
160      * be appropriate.  This is issued after both key/value and full data restore
161      * operations have completed.
162      *
163      * @param token Opaque token identifying this transaction.  This must
164      *        be echoed back to the backup service binder once the agent is
165      *        finished restoring the application based on the restore data
166      *        contents.
167      * @param callbackBinder Binder on which to indicate operation completion,
168      *        passed here as a convenience to the agent.
169      */
doRestoreFinished(int token, IBackupManager callbackBinder)170     void doRestoreFinished(int token, IBackupManager callbackBinder);
171 
172     /**
173      * Out of band: instruct the agent to crash within the client process.  This is used
174      * when the backup infrastructure detects a semantic error post-hoc and needs to
175      * pass the problem back to the app.
176      *
177      * @param message The message to be passed to the agent's application in an exception.
178      */
fail(String message)179     void fail(String message);
180 }
181