Merge change 5196 into donut

* changes:
  Modify the IBackupTransport API to support bulk restore operations. Change the BackupManagerService and LocalTransport to support the new API.

3 files changed, 105 insertions, 117 deletions

diff --git a/core/java/android/backup/RestoreSet.java b/core/java/android/backup/RestoreSet.java
index 96a99aea0deb..eeca148667f3 100644
--- a/core/java/android/backup/RestoreSet.java
+++ b/core/java/android/backup/RestoreSet.java
@@ -43,14 +43,14 @@ public class RestoreSet implements Parcelable {
      * transport.  This is guaranteed to be valid for the duration of a restore
      * session, but is meaningless once the session has ended.
      */
-    public int token;
+    public long token;
 
 
     public RestoreSet() {
         // Leave everything zero / null
     }
 
-    public RestoreSet(String _name, String _dev, int _token) {
+    public RestoreSet(String _name, String _dev, long _token) {
         name = _name;
         device = _dev;
         token = _token;
@@ -65,7 +65,7 @@ public class RestoreSet implements Parcelable {
     public void writeToParcel(Parcel out, int flags) {
         out.writeString(name);
         out.writeString(device);
-        out.writeInt(token);
+        out.writeLong(token);
     }
 
     public static final Parcelable.Creator<RestoreSet> CREATOR
@@ -82,6 +82,6 @@ public class RestoreSet implements Parcelable {
     private RestoreSet(Parcel in) {
         name = in.readString();
         device = in.readString();
-        token = in.readInt();
+        token = in.readLong();
     }
-}
\ No newline at end of file
+}
diff --git a/core/java/com/android/internal/backup/IBackupTransport.aidl b/core/java/com/android/internal/backup/IBackupTransport.aidl
index 84ed729cb7ae..ec6352818ad9 100644
--- a/core/java/com/android/internal/backup/IBackupTransport.aidl
+++ b/core/java/com/android/internal/backup/IBackupTransport.aidl
@@ -54,63 +54,70 @@ interface IBackupTransport {
     long requestBackupTime();
 
     /**
-     * Establish a connection to the back-end data repository, if necessary.  If the transport
-     * needs to initialize state that is not tied to individual applications' backup operations,
-     * this is where it should be done.
-     *
-     * @return Zero on success; a nonzero error code on failure.
-     */
-    int startSession();
-
-    /**
-     * Send one application's data to the backup destination.
+     * Send one application's data to the backup destination.  The transport may send
+     * the data immediately, or may buffer it.  After this is called, {@link #finishBackup}
+     * must be called to ensure the data is sent and recorded successfully.
      *
      * @param packageInfo The identity of the application whose data is being backed up.
      *   This specifically includes the signature list for the package.
      * @param data The data stream that resulted from invoking the application's
      *   BackupService.doBackup() method.  This may be a pipe rather than a file on
      *   persistent media, so it may not be seekable.
-     * @return Zero on success; a nonzero error code on failure.
+     * @return false if errors occurred (the backup should be aborted and rescheduled),
+     *   true if everything is OK so far (but {@link #finishBackup} must be called).
      */
-    int performBackup(in PackageInfo packageInfo, in ParcelFileDescriptor data);
+    boolean performBackup(in PackageInfo packageInfo, in ParcelFileDescriptor inFd);
+
+    /**
+     * Finish sending application data to the backup destination.  This must be
+     * called after {@link #performBackup} to ensure that all data is sent.  Only
+     * when this method returns true can the backup be assumed to have succeeded.
+     *
+     * @return false if errors occurred (the backup should be aborted and rescheduled),
+     *   true if everything is OK so far (but {@link #finishBackup} must be called).
+     */
+    boolean finishBackup();
 
     /**
      * Get the set of backups currently available over this transport.
      *
-     * @return Descriptions of the set of restore images available for this device.
+     * @return Descriptions of the set of restore images available for this device,
+     *   or null if an error occurred (the attempt should be rescheduled).
      **/
     RestoreSet[] getAvailableRestoreSets();
 
     /**
-     * Get the set of applications from a given restore image.
+     * Start restoring application data from backup.  After calling this function,
+     * alternate calls to {@link #nextRestorePackage} and {@link #nextRestoreData}
+     * to walk through the actual application data.
      *
      * @param token A backup token as returned by {@link #getAvailableRestoreSets}.
-     * @return An array of PackageInfo objects describing all of the applications
-     *   available for restore from this restore image.  This should include the list
-     *   of signatures for each package so that the Backup Manager can filter using that
-     *   information.
+     * @param packages List of applications to restore (if data is available).
+     *   Application data will be restored in the order given.
+     * @return false if errors occurred (the restore should be aborted and rescheduled),
+     *   true if everything is OK so far (go ahead and call {@link #nextRestorePackage}).
      */
-    PackageInfo[] getAppSet(int token);
+    boolean startRestore(long token, in PackageInfo[] packages);
 
     /**
-     * Retrieve one application's data from the backing store.
-     *
-     * @param token The backup record from which a restore is being requested.
-     * @param packageInfo The identity of the application whose data is being restored.
-     *   This must include the signature list for the package; it is up to the transport
-     *   to verify that the requested app's signatures match the saved backup record
-     *   because the transport cannot necessarily trust the client device.
-     * @param data An open, writable file into which the backup image should be stored.
-     * @return Zero on success; a nonzero error code on failure.
+     * Get the package name of the next application with data in the backup store.
+     * @return The name of one of the packages supplied to {@link #startRestore},
+     *   or "" (the empty string) if no more backup data is available,
+     *   or null if an error occurred (the restore should be aborted and rescheduled).
      */
-    int getRestoreData(int token, in PackageInfo packageInfo, in ParcelFileDescriptor data);
+    String nextRestorePackage();
 
     /**
-     * Terminate the backup session, closing files, freeing memory, and cleaning up whatever
-     * other state the transport required.
-     *
-     * @return Zero on success; a nonzero error code on failure.  Even on failure, the session
-     *         is torn down and must be restarted if another backup is attempted.
+     * Get the data for the application returned by {@link #nextRestorePackage}.
+     * @param data An open, writable file into which the backup data should be stored.
+     * @return false if errors occurred (the restore should be aborted and rescheduled),
+     *   true if everything is OK so far (go ahead and call {@link #nextRestorePackage}).
+     */
+    boolean getRestoreData(in ParcelFileDescriptor outFd);
+
+    /**
+     * End a restore session (aborting any in-process data transfer as necessary),
+     * freeing any resources and connections used during the restore process.
      */
-    int endSession();
+    void finishRestore();
 }
diff --git a/core/java/com/android/internal/backup/LocalTransport.java b/core/java/com/android/internal/backup/LocalTransport.java
index 3dd71f315425..0fbbb3fb06d0 100644
--- a/core/java/com/android/internal/backup/LocalTransport.java
+++ b/core/java/com/android/internal/backup/LocalTransport.java
@@ -33,11 +33,8 @@ public class LocalTransport extends IBackupTransport.Stub {
     private Context mContext;
     private PackageManager mPackageManager;
     private File mDataDir = new File(Environment.getDownloadCacheDirectory(), "backup");
-    private FileFilter mDirFileFilter = new FileFilter() {
-        public boolean accept(File f) {
-            return f.isDirectory();
-        }
-    };
+    private PackageInfo[] mRestorePackages = null;
+    private int mRestorePackage = -1;  // Index into mRestorePackages
 
 
     public LocalTransport(Context context) {
@@ -51,21 +48,9 @@ public class LocalTransport extends IBackupTransport.Stub {
         return 0;
     }
 
-    public int startSession() throws RemoteException {
-        if (DEBUG) Log.v(TAG, "session started");
-        mDataDir.mkdirs();
-        return 0;
-    }
-
-    public int endSession() throws RemoteException {
-        if (DEBUG) Log.v(TAG, "session ended");
-        return 0;
-    }
-
-    public int performBackup(PackageInfo packageInfo, ParcelFileDescriptor data)
+    public boolean performBackup(PackageInfo packageInfo, ParcelFileDescriptor data)
             throws RemoteException {
         if (DEBUG) Log.v(TAG, "performBackup() pkg=" + packageInfo.packageName);
-        int err = 0;
 
         File packageDir = new File(mDataDir, packageInfo.packageName);
         packageDir.mkdirs();
@@ -101,9 +86,8 @@ public class LocalTransport extends IBackupTransport.Stub {
                     try {
                         entity.write(buf, 0, dataSize);
                     } catch (IOException e) {
-                        Log.e(TAG, "Unable to update key file "
-                                + entityFile.getAbsolutePath());
-                        err = -1;
+                        Log.e(TAG, "Unable to update key file " + entityFile.getAbsolutePath());
+                        return false;
                     } finally {
                         entity.close();
                     }
@@ -111,14 +95,17 @@ public class LocalTransport extends IBackupTransport.Stub {
                     entityFile.delete();
                 }
             }
+            return true;
         } catch (IOException e) {
             // oops, something went wrong.  abort the operation and return error.
-            Log.v(TAG, "Exception reading backup input:");
-            e.printStackTrace();
-            err = -1;
+            Log.v(TAG, "Exception reading backup input:", e);
+            return false;
         }
+    }
 
-        return err;
+    public boolean finishBackup() throws RemoteException {
+        if (DEBUG) Log.v(TAG, "finishBackup()");
+        return true;
     }
 
     // Restore handling
@@ -129,72 +116,66 @@ public class LocalTransport extends IBackupTransport.Stub {
         return array;
     }
 
-    public PackageInfo[] getAppSet(int token) throws android.os.RemoteException {
-        if (DEBUG) Log.v(TAG, "getting app set " + token);
-        // the available packages are the extant subdirs of mDatadir
-        File[] packageDirs = mDataDir.listFiles(mDirFileFilter);
-        ArrayList<PackageInfo> packages = new ArrayList<PackageInfo>();
-        for (File dir : packageDirs) {
-            try {
-                PackageInfo pkg = mPackageManager.getPackageInfo(dir.getName(),
-                        PackageManager.GET_SIGNATURES);
-                if (pkg != null) {
-                    packages.add(pkg);
-                }
-            } catch (NameNotFoundException e) {
-                // restore set contains data for a package not installed on the
-                // phone -- just ignore it.
-            }
-        }
+    public boolean startRestore(long token, PackageInfo[] packages) {
+        if (DEBUG) Log.v(TAG, "start restore " + token);
+        mRestorePackages = packages;
+        mRestorePackage = -1;
+        return true;
+    }
 
-        if (DEBUG) {
-            Log.v(TAG, "Built app set of " + packages.size() + " entries:");
-            for (PackageInfo p : packages) {
-                Log.v(TAG, "    + " + p.packageName);
+    public String nextRestorePackage() {
+        if (mRestorePackages == null) throw new IllegalStateException("startRestore not called");
+        while (++mRestorePackage < mRestorePackages.length) {
+            String name = mRestorePackages[mRestorePackage].packageName;
+            if (new File(mDataDir, name).isDirectory()) {
+                if (DEBUG) Log.v(TAG, "  nextRestorePackage() = " + name);
+                return name;
             }
         }
 
-        PackageInfo[] result = new PackageInfo[packages.size()];
-        return packages.toArray(result);
+        if (DEBUG) Log.v(TAG, "  no more packages to restore");
+        return "";
     }
 
-    public int getRestoreData(int token, PackageInfo packageInfo, ParcelFileDescriptor outFd)
-            throws android.os.RemoteException {
-        if (DEBUG) Log.v(TAG, "getting restore data " + token + " : " + packageInfo.packageName);
-        // we only support one hardcoded restore set
-        if (token != 0) return -1;
-
-        // the data for a given package is at a known location
-        File packageDir = new File(mDataDir, packageInfo.packageName);
+    public boolean getRestoreData(ParcelFileDescriptor outFd) {
+        if (mRestorePackages == null) throw new IllegalStateException("startRestore not called");
+        if (mRestorePackage < 0) throw new IllegalStateException("nextRestorePackage not called");
+        File packageDir = new File(mDataDir, mRestorePackages[mRestorePackage].packageName);
 
         // The restore set is the concatenation of the individual record blobs,
         // each of which is a file in the package's directory
         File[] blobs = packageDir.listFiles();
-        if (DEBUG) Log.v(TAG, "   found " + blobs.length + " key files");
-        int err = 0;
-        if (blobs != null && blobs.length > 0) {
-            BackupDataOutput out = new BackupDataOutput(outFd.getFileDescriptor());
-            try {
-                for (File f : blobs) {
-                    copyToRestoreData(f, out);
+        if (blobs == null) {
+            Log.e(TAG, "Error listing directory: " + packageDir);
+            return false;  // nextRestorePackage() ensures the dir exists, so this is an error
+        }
+
+        // We expect at least some data if the directory exists in the first place
+        if (DEBUG) Log.v(TAG, "  getRestoreData() found " + blobs.length + " key files");
+        BackupDataOutput out = new BackupDataOutput(outFd.getFileDescriptor());
+        try {
+            for (File f : blobs) {
+                FileInputStream in = new FileInputStream(f);
+                try {
+                    int size = (int) f.length();
+                    byte[] buf = new byte[size];
+                    in.read(buf);
+                    String key = new String(Base64.decode(f.getName()));
+                    if (DEBUG) Log.v(TAG, "    ... key=" + key + " size=" + size);
+                    out.writeEntityHeader(key, size);
+                    out.writeEntityData(buf, size);
+                } finally {
+                    in.close();
                 }
-            } catch (Exception e) {
-                Log.e(TAG, "Unable to read backup records");
-                err = -1;
             }
+            return true;
+        } catch (IOException e) {
+            Log.e(TAG, "Unable to read backup records", e);
+            return false;
         }
-        return err;
     }
 
-    private void copyToRestoreData(File f, BackupDataOutput out) throws IOException {
-        FileInputStream in = new FileInputStream(f);
-        int size = (int) f.length();
-        byte[] buf = new byte[size];
-        in.read(buf);
-        String key = new String(Base64.decode(f.getName()));
-        if (DEBUG) Log.v(TAG, "   ... copy to stream: key=" + key
-                + " size=" + size);
-        out.writeEntityHeader(key, size);
-        out.writeEntityData(buf, size);
+    public void finishRestore() {
+        if (DEBUG) Log.v(TAG, "finishRestore()");
     }
 }