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      1 /*
      2  * Copyright (C) 2014 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.backup;
     18 
     19 import android.annotation.SystemApi;
     20 import android.content.Intent;
     21 import android.content.pm.PackageInfo;
     22 import android.os.IBinder;
     23 import android.os.ParcelFileDescriptor;
     24 import android.os.RemoteException;
     25 
     26 import com.android.internal.backup.IBackupTransport;
     27 
     28 /**
     29  * Concrete class that provides a stable-API bridge between IBackupTransport
     30  * and its implementations.
     31  *
     32  * @hide
     33  */
     34 @SystemApi
     35 public class BackupTransport {
     36     // Zero return always means things are okay.  If returned from
     37     // getNextFullRestoreDataChunk(), it means that no data could be delivered at
     38     // this time, but the restore is still running and the caller should simply
     39     // retry.
     40     public static final int TRANSPORT_OK = 0;
     41 
     42     // -1 is special; it is used in getNextFullRestoreDataChunk() to indicate that
     43     // we've delivered the entire data stream for the current restore target.
     44     public static final int NO_MORE_DATA = -1;
     45 
     46     // Result codes that indicate real errors are negative and not -1
     47     public static final int TRANSPORT_ERROR = -1000;
     48     public static final int TRANSPORT_NOT_INITIALIZED = -1001;
     49     public static final int TRANSPORT_PACKAGE_REJECTED = -1002;
     50     public static final int AGENT_ERROR = -1003;
     51     public static final int AGENT_UNKNOWN = -1004;
     52     public static final int TRANSPORT_QUOTA_EXCEEDED = -1005;
     53 
     54     // Indicates that operation was initiated by user, not a scheduled one.
     55     // Transport should ignore its own moratoriums for call with this flag set.
     56     public static final int FLAG_USER_INITIATED = 1;
     57 
     58     IBackupTransport mBinderImpl = new TransportImpl();
     59 
     60     public IBinder getBinder() {
     61         return mBinderImpl.asBinder();
     62     }
     63 
     64     // ------------------------------------------------------------------------------------
     65     // Transport self-description and general configuration interfaces
     66     //
     67 
     68     /**
     69      * Ask the transport for the name under which it should be registered.  This will
     70      * typically be its host service's component name, but need not be.
     71      */
     72     public String name() {
     73         throw new UnsupportedOperationException("Transport name() not implemented");
     74     }
     75 
     76     /**
     77      * Ask the transport for an Intent that can be used to launch any internal
     78      * configuration Activity that it wishes to present.  For example, the transport
     79      * may offer a UI for allowing the user to supply login credentials for the
     80      * transport's off-device backend.
     81      *
     82      * <p>If the transport does not supply any user-facing configuration UI, it should
     83      * return {@code null} from this method.
     84      *
     85      * @return An Intent that can be passed to Context.startActivity() in order to
     86      *         launch the transport's configuration UI.  This method will return {@code null}
     87      *         if the transport does not offer any user-facing configuration UI.
     88      */
     89     public Intent configurationIntent() {
     90         return null;
     91     }
     92 
     93     /**
     94      * On demand, supply a one-line string that can be shown to the user that
     95      * describes the current backend destination.  For example, a transport that
     96      * can potentially associate backup data with arbitrary user accounts should
     97      * include the name of the currently-active account here.
     98      *
     99      * @return A string describing the destination to which the transport is currently
    100      *         sending data.  This method should not return null.
    101      */
    102     public String currentDestinationString() {
    103         throw new UnsupportedOperationException(
    104                 "Transport currentDestinationString() not implemented");
    105     }
    106 
    107     /**
    108      * Ask the transport for an Intent that can be used to launch a more detailed
    109      * secondary data management activity.  For example, the configuration intent might
    110      * be one for allowing the user to select which account they wish to associate
    111      * their backups with, and the management intent might be one which presents a
    112      * UI for managing the data on the backend.
    113      *
    114      * <p>In the Settings UI, the configuration intent will typically be invoked
    115      * when the user taps on the preferences item labeled with the current
    116      * destination string, and the management intent will be placed in an overflow
    117      * menu labelled with the management label string.
    118      *
    119      * <p>If the transport does not supply any user-facing data management
    120      * UI, then it should return {@code null} from this method.
    121      *
    122      * @return An intent that can be passed to Context.startActivity() in order to
    123      *         launch the transport's data-management UI.  This method will return
    124      *         {@code null} if the transport does not offer any user-facing data
    125      *         management UI.
    126      */
    127     public Intent dataManagementIntent() {
    128         return null;
    129     }
    130 
    131     /**
    132      * On demand, supply a short string that can be shown to the user as the label
    133      * on an overflow menu item used to invoked the data management UI.
    134      *
    135      * @return A string to be used as the label for the transport's data management
    136      *         affordance.  If the transport supplies a data management intent, this
    137      *         method must not return {@code null}.
    138      */
    139     public String dataManagementLabel() {
    140         throw new UnsupportedOperationException(
    141                 "Transport dataManagementLabel() not implemented");
    142     }
    143 
    144     /**
    145      * Ask the transport where, on local device storage, to keep backup state blobs.
    146      * This is per-transport so that mock transports used for testing can coexist with
    147      * "live" backup services without interfering with the live bookkeeping.  The
    148      * returned string should be a name that is expected to be unambiguous among all
    149      * available backup transports; the name of the class implementing the transport
    150      * is a good choice.
    151      *
    152      * @return A unique name, suitable for use as a file or directory name, that the
    153      *         Backup Manager could use to disambiguate state files associated with
    154      *         different backup transports.
    155      */
    156     public String transportDirName() {
    157         throw new UnsupportedOperationException(
    158                 "Transport transportDirName() not implemented");
    159     }
    160 
    161     // ------------------------------------------------------------------------------------
    162     // Device-level operations common to both key/value and full-data storage
    163 
    164     /**
    165      * Initialize the server side storage for this device, erasing all stored data.
    166      * The transport may send the request immediately, or may buffer it.  After
    167      * this is called, {@link #finishBackup} will be called to ensure the request
    168      * is sent and received successfully.
    169      *
    170      * <p>If the transport returns anything other than TRANSPORT_OK from this method,
    171      * the OS will halt the current initialize operation and schedule a retry in the
    172      * near future.  Even if the transport is in a state such that attempting to
    173      * "initialize" the backend storage is meaningless -- for example, if there is
    174      * no current live dataset at all, or there is no authenticated account under which
    175      * to store the data remotely -- the transport should return TRANSPORT_OK here
    176      * and treat the initializeDevice() / finishBackup() pair as a graceful no-op.
    177      *
    178      * @return One of {@link BackupTransport#TRANSPORT_OK} (OK so far) or
    179      *   {@link BackupTransport#TRANSPORT_ERROR} (to retry following network error
    180      *   or other failure).
    181      */
    182     public int initializeDevice() {
    183         return BackupTransport.TRANSPORT_ERROR;
    184     }
    185 
    186     /**
    187      * Erase the given application's data from the backup destination.  This clears
    188      * out the given package's data from the current backup set, making it as though
    189      * the app had never yet been backed up.  After this is called, {@link finishBackup}
    190      * must be called to ensure that the operation is recorded successfully.
    191      *
    192      * @return the same error codes as {@link #performBackup}.
    193      */
    194     public int clearBackupData(PackageInfo packageInfo) {
    195         return BackupTransport.TRANSPORT_ERROR;
    196     }
    197 
    198     /**
    199      * Finish sending application data to the backup destination.  This must be
    200      * called after {@link #performBackup}, {@link #performFullBackup}, or {@link clearBackupData}
    201      * to ensure that all data is sent and the operation properly finalized.  Only when this
    202      * method returns true can a backup be assumed to have succeeded.
    203      *
    204      * @return the same error codes as {@link #performBackup} or {@link #performFullBackup}.
    205      */
    206     public int finishBackup() {
    207         return BackupTransport.TRANSPORT_ERROR;
    208     }
    209 
    210     // ------------------------------------------------------------------------------------
    211     // Key/value incremental backup support interfaces
    212 
    213     /**
    214      * Verify that this is a suitable time for a key/value backup pass.  This should return zero
    215      * if a backup is reasonable right now, some positive value otherwise.  This method
    216      * will be called outside of the {@link #performBackup}/{@link #finishBackup} pair.
    217      *
    218      * <p>If this is not a suitable time for a backup, the transport should return a
    219      * backoff delay, in milliseconds, after which the Backup Manager should try again.
    220      *
    221      * @return Zero if this is a suitable time for a backup pass, or a positive time delay
    222      *   in milliseconds to suggest deferring the backup pass for a while.
    223      */
    224     public long requestBackupTime() {
    225         return 0;
    226     }
    227 
    228     /**
    229      * Send one application's key/value data update to the backup destination.  The
    230      * transport may send the data immediately, or may buffer it.  If this method returns
    231      * {@link #TRANSPORT_OK}, {@link #finishBackup} will then be called to ensure the data
    232      * is sent and recorded successfully.
    233      *
    234      * @param packageInfo The identity of the application whose data is being backed up.
    235      *   This specifically includes the signature list for the package.
    236      * @param inFd Descriptor of file with data that resulted from invoking the application's
    237      *   BackupService.doBackup() method.  This may be a pipe rather than a file on
    238      *   persistent media, so it may not be seekable.
    239      * @param flags {@link BackupTransport#FLAG_USER_INITIATED} or 0.
    240      * @return one of {@link BackupTransport#TRANSPORT_OK} (OK so far),
    241      *  {@link BackupTransport#TRANSPORT_PACKAGE_REJECTED} (to suppress backup of this
    242      *  specific package, but allow others to proceed),
    243      *  {@link BackupTransport#TRANSPORT_ERROR} (on network error or other failure), or
    244      *  {@link BackupTransport#TRANSPORT_NOT_INITIALIZED} (if the backend dataset has
    245      *  become lost due to inactivity purge or some other reason and needs re-initializing)
    246      */
    247     public int performBackup(PackageInfo packageInfo, ParcelFileDescriptor inFd, int flags) {
    248         return performBackup(packageInfo, inFd);
    249     }
    250 
    251     /**
    252      * Legacy version of {@link #performBackup(PackageInfo, ParcelFileDescriptor, int)} that
    253      * doesn't use flags parameter.
    254      */
    255     public int performBackup(PackageInfo packageInfo, ParcelFileDescriptor inFd) {
    256         return BackupTransport.TRANSPORT_ERROR;
    257     }
    258 
    259     // ------------------------------------------------------------------------------------
    260     // Key/value dataset restore interfaces
    261 
    262     /**
    263      * Get the set of all backups currently available over this transport.
    264      *
    265      * @return Descriptions of the set of restore images available for this device,
    266      *   or null if an error occurred (the attempt should be rescheduled).
    267      **/
    268     public RestoreSet[] getAvailableRestoreSets() {
    269         return null;
    270     }
    271 
    272     /**
    273      * Get the identifying token of the backup set currently being stored from
    274      * this device.  This is used in the case of applications wishing to restore
    275      * their last-known-good data.
    276      *
    277      * @return A token that can be passed to {@link #startRestore}, or 0 if there
    278      *   is no backup set available corresponding to the current device state.
    279      */
    280     public long getCurrentRestoreSet() {
    281         return 0;
    282     }
    283 
    284     /**
    285      * Start restoring application data from backup.  After calling this function,
    286      * alternate calls to {@link #nextRestorePackage} and {@link #nextRestoreData}
    287      * to walk through the actual application data.
    288      *
    289      * @param token A backup token as returned by {@link #getAvailableRestoreSets}
    290      *   or {@link #getCurrentRestoreSet}.
    291      * @param packages List of applications to restore (if data is available).
    292      *   Application data will be restored in the order given.
    293      * @return One of {@link BackupTransport#TRANSPORT_OK} (OK so far, call
    294      *   {@link #nextRestorePackage}) or {@link BackupTransport#TRANSPORT_ERROR}
    295      *   (an error occurred, the restore should be aborted and rescheduled).
    296      */
    297     public int startRestore(long token, PackageInfo[] packages) {
    298         return BackupTransport.TRANSPORT_ERROR;
    299     }
    300 
    301     /**
    302      * Get the package name of the next application with data in the backup store, plus
    303      * a description of the structure of the restored archive: either TYPE_KEY_VALUE for
    304      * an original-API key/value dataset, or TYPE_FULL_STREAM for a tarball-type archive stream.
    305      *
    306      * <p>If the package name in the returned RestoreDescription object is the singleton
    307      * {@link RestoreDescription#NO_MORE_PACKAGES}, it indicates that no further data is available
    308      * in the current restore session: all packages described in startRestore() have been
    309      * processed.
    310      *
    311      * <p>If this method returns {@code null}, it means that a transport-level error has
    312      * occurred and the entire restore operation should be abandoned.
    313      *
    314      * <p class="note">The OS may call {@link #nextRestorePackage()} multiple times
    315      * before calling either {@link #getRestoreData(ParcelFileDescriptor) getRestoreData()}
    316      * or {@link #getNextFullRestoreDataChunk(ParcelFileDescriptor) getNextFullRestoreDataChunk()}.
    317      * It does this when it has determined that it needs to skip restore of one or more
    318      * packages.  The transport should not actually transfer any restore data for
    319      * the given package in response to {@link #nextRestorePackage()}, but rather wait
    320      * for an explicit request before doing so.
    321      *
    322      * @return A RestoreDescription object containing the name of one of the packages
    323      *   supplied to {@link #startRestore} plus an indicator of the data type of that
    324      *   restore data; or {@link RestoreDescription#NO_MORE_PACKAGES} to indicate that
    325      *   no more packages can be restored in this session; or {@code null} to indicate
    326      *   a transport-level error.
    327      */
    328     public RestoreDescription nextRestorePackage() {
    329         return null;
    330     }
    331 
    332     /**
    333      * Get the data for the application returned by {@link #nextRestorePackage}, if that
    334      * method reported {@link RestoreDescription#TYPE_KEY_VALUE} as its delivery type.
    335      * If the package has only TYPE_FULL_STREAM data, then this method will return an
    336      * error.
    337      *
    338      * @param data An open, writable file into which the key/value backup data should be stored.
    339      * @return the same error codes as {@link #startRestore}.
    340      */
    341     public int getRestoreData(ParcelFileDescriptor outFd) {
    342         return BackupTransport.TRANSPORT_ERROR;
    343     }
    344 
    345     /**
    346      * End a restore session (aborting any in-process data transfer as necessary),
    347      * freeing any resources and connections used during the restore process.
    348      */
    349     public void finishRestore() {
    350         throw new UnsupportedOperationException(
    351                 "Transport finishRestore() not implemented");
    352     }
    353 
    354     // ------------------------------------------------------------------------------------
    355     // Full backup interfaces
    356 
    357     /**
    358      * Verify that this is a suitable time for a full-data backup pass.  This should return zero
    359      * if a backup is reasonable right now, some positive value otherwise.  This method
    360      * will be called outside of the {@link #performFullBackup}/{@link #finishBackup} pair.
    361      *
    362      * <p>If this is not a suitable time for a backup, the transport should return a
    363      * backoff delay, in milliseconds, after which the Backup Manager should try again.
    364      *
    365      * @return Zero if this is a suitable time for a backup pass, or a positive time delay
    366      *   in milliseconds to suggest deferring the backup pass for a while.
    367      *
    368      * @see #requestBackupTime()
    369      */
    370     public long requestFullBackupTime() {
    371         return 0;
    372     }
    373 
    374     /**
    375      * Begin the process of sending an application's full-data archive to the backend.
    376      * The description of the package whose data will be delivered is provided, as well as
    377      * the socket file descriptor on which the transport will receive the data itself.
    378      *
    379      * <p>If the package is not eligible for backup, the transport should return
    380      * {@link BackupTransport#TRANSPORT_PACKAGE_REJECTED}.  In this case the system will
    381      * simply proceed with the next candidate if any, or finish the full backup operation
    382      * if all apps have been processed.
    383      *
    384      * <p>After the transport returns {@link BackupTransport#TRANSPORT_OK} from this
    385      * method, the OS will proceed to call {@link #sendBackupData()} one or more times
    386      * to deliver the application's data as a streamed tarball.  The transport should not
    387      * read() from the socket except as instructed to via the {@link #sendBackupData(int)}
    388      * method.
    389      *
    390      * <p>After all data has been delivered to the transport, the system will call
    391      * {@link #finishBackup()}.  At this point the transport should commit the data to
    392      * its datastore, if appropriate, and close the socket that had been provided in
    393      * {@link #performFullBackup(PackageInfo, ParcelFileDescriptor)}.
    394      *
    395      * <p class="note">If the transport returns TRANSPORT_OK from this method, then the
    396      * OS will always provide a matching call to {@link #finishBackup()} even if sending
    397      * data via {@link #sendBackupData(int)} failed at some point.
    398      *
    399      * @param targetPackage The package whose data is to follow.
    400      * @param socket The socket file descriptor through which the data will be provided.
    401      *    If the transport returns {@link #TRANSPORT_PACKAGE_REJECTED} here, it must still
    402      *    close this file descriptor now; otherwise it should be cached for use during
    403      *    succeeding calls to {@link #sendBackupData(int)}, and closed in response to
    404      *    {@link #finishBackup()}.
    405      * @param flags {@link BackupTransport#FLAG_USER_INITIATED} or 0.
    406      * @return TRANSPORT_PACKAGE_REJECTED to indicate that the stated application is not
    407      *    to be backed up; TRANSPORT_OK to indicate that the OS may proceed with delivering
    408      *    backup data; TRANSPORT_ERROR to indicate a fatal error condition that precludes
    409      *    performing a backup at this time.
    410      */
    411     public int performFullBackup(PackageInfo targetPackage, ParcelFileDescriptor socket,
    412             int flags) {
    413         return performFullBackup(targetPackage, socket);
    414     }
    415 
    416     /**
    417      * Legacy version of {@link #performFullBackup(PackageInfo, ParcelFileDescriptor, int)} that
    418      * doesn't use flags parameter.
    419      */
    420     public int performFullBackup(PackageInfo targetPackage, ParcelFileDescriptor socket) {
    421         return BackupTransport.TRANSPORT_PACKAGE_REJECTED;
    422     }
    423 
    424     /**
    425      * Called after {@link #performFullBackup} to make sure that the transport is willing to
    426      * handle a full-data backup operation of the specified size on the current package.
    427      * If the transport returns anything other than TRANSPORT_OK, the package's backup
    428      * operation will be skipped (and {@link #finishBackup() invoked} with no data for that
    429      * package being passed to {@link #sendBackupData}.
    430      *
    431      * <p class="note">The platform does no size-based rejection of full backup attempts on
    432      * its own: it is always the responsibility of the transport to implement its own policy.
    433      * In particular, even if the preflighted payload size is zero, the platform will still call
    434      * this method and will proceed to back up an archive metadata header with no file content
    435      * if this method returns TRANSPORT_OK.  To avoid storing such payloads the transport
    436      * must recognize this case and return TRANSPORT_PACKAGE_REJECTED.
    437      *
    438      * Added in {@link android.os.Build.VERSION_CODES#M}.
    439      *
    440      * @param size The estimated size of the full-data payload for this app.  This includes
    441      *         manifest and archive format overhead, but is not guaranteed to be precise.
    442      * @return TRANSPORT_OK if the platform is to proceed with the full-data backup,
    443      *         TRANSPORT_PACKAGE_REJECTED if the proposed payload size is too large for
    444      *         the transport to handle, or TRANSPORT_ERROR to indicate a fatal error
    445      *         condition that means the platform cannot perform a backup at this time.
    446      */
    447     public int checkFullBackupSize(long size) {
    448         return BackupTransport.TRANSPORT_OK;
    449     }
    450 
    451     /**
    452      * Tells the transport to read {@code numBytes} bytes of data from the socket file
    453      * descriptor provided in the {@link #performFullBackup(PackageInfo, ParcelFileDescriptor)}
    454      * call, and deliver those bytes to the datastore.
    455      *
    456      * @param numBytes The number of bytes of tarball data available to be read from the
    457      *    socket.
    458      * @return TRANSPORT_OK on successful processing of the data; TRANSPORT_ERROR to
    459      *    indicate a fatal error situation.  If an error is returned, the system will
    460      *    call finishBackup() and stop attempting backups until after a backoff and retry
    461      *    interval.
    462      */
    463     public int sendBackupData(int numBytes) {
    464         return BackupTransport.TRANSPORT_ERROR;
    465     }
    466 
    467     /**
    468      * Tells the transport to cancel the currently-ongoing full backup operation.  This
    469      * will happen between {@link #performFullBackup()} and {@link #finishBackup()}
    470      * if the OS needs to abort the backup operation for any reason, such as a crash in
    471      * the application undergoing backup.
    472      *
    473      * <p>When it receives this call, the transport should discard any partial archive
    474      * that it has stored so far.  If possible it should also roll back to the previous
    475      * known-good archive in its datastore.
    476      *
    477      * <p>If the transport receives this callback, it will <em>not</em> receive a
    478      * call to {@link #finishBackup()}.  It needs to tear down any ongoing backup state
    479      * here.
    480      */
    481     public void cancelFullBackup() {
    482         throw new UnsupportedOperationException(
    483                 "Transport cancelFullBackup() not implemented");
    484     }
    485 
    486     /**
    487      * Ask the transport whether this app is eligible for backup.
    488      *
    489      * @param targetPackage The identity of the application.
    490      * @param isFullBackup If set, transport should check if app is eligible for full data backup,
    491      *   otherwise to check if eligible for key-value backup.
    492      * @return Whether this app is eligible for backup.
    493      */
    494     public boolean isAppEligibleForBackup(PackageInfo targetPackage, boolean isFullBackup) {
    495         return true;
    496     }
    497 
    498     /**
    499      * Ask the transport about current quota for backup size of the package.
    500      *
    501      * @param packageName ID of package to provide the quota.
    502      * @param isFullBackup If set, transport should return limit for full data backup, otherwise
    503      *                     for key-value backup.
    504      * @return Current limit on backup size in bytes.
    505      */
    506     public long getBackupQuota(String packageName, boolean isFullBackup) {
    507         return Long.MAX_VALUE;
    508     }
    509 
    510     // ------------------------------------------------------------------------------------
    511     // Full restore interfaces
    512 
    513     /**
    514      * Ask the transport to provide data for the "current" package being restored.  This
    515      * is the package that was just reported by {@link #nextRestorePackage()} as having
    516      * {@link RestoreDescription#TYPE_FULL_STREAM} data.
    517      *
    518      * The transport writes some data to the socket supplied to this call, and returns
    519      * the number of bytes written.  The system will then read that many bytes and
    520      * stream them to the application's agent for restore, then will call this method again
    521      * to receive the next chunk of the archive.  This sequence will be repeated until the
    522      * transport returns zero indicating that all of the package's data has been delivered
    523      * (or returns a negative value indicating some sort of hard error condition at the
    524      * transport level).
    525      *
    526      * <p>After this method returns zero, the system will then call
    527      * {@link #nextRestorePackage()} to begin the restore process for the next
    528      * application, and the sequence begins again.
    529      *
    530      * <p>The transport should always close this socket when returning from this method.
    531      * Do not cache this socket across multiple calls or you may leak file descriptors.
    532      *
    533      * @param socket The file descriptor that the transport will use for delivering the
    534      *    streamed archive.  The transport must close this socket in all cases when returning
    535      *    from this method.
    536      * @return {@link #NO_MORE_DATA} when no more data for the current package is available.
    537      *    A positive value indicates the presence of that many bytes to be delivered to the app.
    538      *    A value of zero indicates that no data was deliverable at this time, but the restore
    539      *    is still running and the caller should retry.  {@link #TRANSPORT_PACKAGE_REJECTED}
    540      *    means that the current package's restore operation should be aborted, but that
    541      *    the transport itself is still in a good state and so a multiple-package restore
    542      *    sequence can still be continued.  Any other negative return value is treated as a
    543      *    fatal error condition that aborts all further restore operations on the current dataset.
    544      */
    545     public int getNextFullRestoreDataChunk(ParcelFileDescriptor socket) {
    546         return 0;
    547     }
    548 
    549     /**
    550      * If the OS encounters an error while processing {@link RestoreDescription#TYPE_FULL_STREAM}
    551      * data for restore, it will invoke this method to tell the transport that it should
    552      * abandon the data download for the current package.  The OS will then either call
    553      * {@link #nextRestorePackage()} again to move on to restoring the next package in the
    554      * set being iterated over, or will call {@link #finishRestore()} to shut down the restore
    555      * operation.
    556      *
    557      * @return {@link #TRANSPORT_OK} if the transport was successful in shutting down the
    558      *    current stream cleanly, or {@link #TRANSPORT_ERROR} to indicate a serious
    559      *    transport-level failure.  If the transport reports an error here, the entire restore
    560      *    operation will immediately be finished with no further attempts to restore app data.
    561      */
    562     public int abortFullRestore() {
    563         return BackupTransport.TRANSPORT_OK;
    564     }
    565 
    566     /**
    567      * Bridge between the actual IBackupTransport implementation and the stable API.  If the
    568      * binder interface needs to change, we use this layer to translate so that we can
    569      * (if appropriate) decouple those framework-side changes from the BackupTransport
    570      * implementations.
    571      */
    572     class TransportImpl extends IBackupTransport.Stub {
    573 
    574         @Override
    575         public String name() throws RemoteException {
    576             return BackupTransport.this.name();
    577         }
    578 
    579         @Override
    580         public Intent configurationIntent() throws RemoteException {
    581             return BackupTransport.this.configurationIntent();
    582         }
    583 
    584         @Override
    585         public String currentDestinationString() throws RemoteException {
    586             return BackupTransport.this.currentDestinationString();
    587         }
    588 
    589         @Override
    590         public Intent dataManagementIntent() {
    591             return BackupTransport.this.dataManagementIntent();
    592         }
    593 
    594         @Override
    595         public String dataManagementLabel() {
    596             return BackupTransport.this.dataManagementLabel();
    597         }
    598 
    599         @Override
    600         public String transportDirName() throws RemoteException {
    601             return BackupTransport.this.transportDirName();
    602         }
    603 
    604         @Override
    605         public long requestBackupTime() throws RemoteException {
    606             return BackupTransport.this.requestBackupTime();
    607         }
    608 
    609         @Override
    610         public int initializeDevice() throws RemoteException {
    611             return BackupTransport.this.initializeDevice();
    612         }
    613 
    614         @Override
    615         public int performBackup(PackageInfo packageInfo, ParcelFileDescriptor inFd, int flags)
    616                 throws RemoteException {
    617             return BackupTransport.this.performBackup(packageInfo, inFd, flags);
    618         }
    619 
    620         @Override
    621         public int clearBackupData(PackageInfo packageInfo) throws RemoteException {
    622             return BackupTransport.this.clearBackupData(packageInfo);
    623         }
    624 
    625         @Override
    626         public int finishBackup() throws RemoteException {
    627             return BackupTransport.this.finishBackup();
    628         }
    629 
    630         @Override
    631         public RestoreSet[] getAvailableRestoreSets() throws RemoteException {
    632             return BackupTransport.this.getAvailableRestoreSets();
    633         }
    634 
    635         @Override
    636         public long getCurrentRestoreSet() throws RemoteException {
    637             return BackupTransport.this.getCurrentRestoreSet();
    638         }
    639 
    640         @Override
    641         public int startRestore(long token, PackageInfo[] packages) throws RemoteException {
    642             return BackupTransport.this.startRestore(token, packages);
    643         }
    644 
    645         @Override
    646         public RestoreDescription nextRestorePackage() throws RemoteException {
    647             return BackupTransport.this.nextRestorePackage();
    648         }
    649 
    650         @Override
    651         public int getRestoreData(ParcelFileDescriptor outFd) throws RemoteException {
    652             return BackupTransport.this.getRestoreData(outFd);
    653         }
    654 
    655         @Override
    656         public void finishRestore() throws RemoteException {
    657             BackupTransport.this.finishRestore();
    658         }
    659 
    660         @Override
    661         public long requestFullBackupTime() throws RemoteException {
    662             return BackupTransport.this.requestFullBackupTime();
    663         }
    664 
    665         @Override
    666         public int performFullBackup(PackageInfo targetPackage, ParcelFileDescriptor socket,
    667                 int flags) throws RemoteException {
    668             return BackupTransport.this.performFullBackup(targetPackage, socket, flags);
    669         }
    670 
    671         @Override
    672         public int checkFullBackupSize(long size) {
    673             return BackupTransport.this.checkFullBackupSize(size);
    674         }
    675 
    676         @Override
    677         public int sendBackupData(int numBytes) throws RemoteException {
    678             return BackupTransport.this.sendBackupData(numBytes);
    679         }
    680 
    681         @Override
    682         public void cancelFullBackup() throws RemoteException {
    683             BackupTransport.this.cancelFullBackup();
    684         }
    685 
    686         @Override
    687         public boolean isAppEligibleForBackup(PackageInfo targetPackage, boolean isFullBackup)
    688                 throws RemoteException {
    689             return BackupTransport.this.isAppEligibleForBackup(targetPackage, isFullBackup);
    690         }
    691 
    692         @Override
    693         public long getBackupQuota(String packageName, boolean isFullBackup) {
    694             return BackupTransport.this.getBackupQuota(packageName, isFullBackup);
    695         }
    696 
    697         @Override
    698         public int getNextFullRestoreDataChunk(ParcelFileDescriptor socket) {
    699             return BackupTransport.this.getNextFullRestoreDataChunk(socket);
    700         }
    701 
    702         @Override
    703         public int abortFullRestore() {
    704             return BackupTransport.this.abortFullRestore();
    705         }
    706     }
    707 }
    708