1 files changed, 133 insertions, 0 deletions
diff --git a/src/com/android/launcher3/LauncherBackupAgent.java b/src/com/android/launcher3/LauncherBackupAgent.java
new file mode 100644
index 000000000..b2f5c5717
--- /dev/null
+++ b/src/com/android/launcher3/LauncherBackupAgent.java
@@ -0,0 +1,133 @@
+package com.android.launcher3;
+
+import android.app.backup.BackupAgent;
+import android.app.backup.BackupDataInput;
+import android.app.backup.BackupDataOutput;
+import android.content.ContentValues;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.os.ParcelFileDescriptor;
+
+import com.android.launcher3.LauncherProvider.DatabaseHelper;
+import com.android.launcher3.LauncherSettings.Favorites;
+import com.android.launcher3.logging.FileLog;
+
+import java.io.InvalidObjectException;
+
+public class LauncherBackupAgent extends BackupAgent {
+
+    private static final String TAG = "LauncherBackupAgent";
+
+    private static final String INFO_COLUMN_NAME = "name";
+    private static final String INFO_COLUMN_DEFAULT_VALUE = "dflt_value";
+
+    @Override
+    public void onRestore(
+            BackupDataInput data, int appVersionCode, ParcelFileDescriptor newState) {
+        // Doesn't do incremental backup/restore
+    }
+
+    @Override
+    public void onBackup(
+            ParcelFileDescriptor oldState, BackupDataOutput data, ParcelFileDescriptor newState) {
+        // Doesn't do incremental backup/restore
+    }
+
+    @Override
+    public void onRestoreFinished() {
+        DatabaseHelper helper = new DatabaseHelper(this, null, LauncherFiles.LAUNCHER_DB);
+
+        if (!sanitizeDBSafely(helper)) {
+            helper.createEmptyDB(helper.getWritableDatabase());
+        }
+
+        try {
+            // Flush all logs before the process is killed.
+            FileLog.flushAll(null);
+        } catch (Exception e) { }
+    }
+
+    private boolean sanitizeDBSafely(DatabaseHelper helper) {
+        SQLiteDatabase db = helper.getWritableDatabase();
+        db.beginTransaction();
+        try {
+            sanitizeDB(helper, db);
+            db.setTransactionSuccessful();
+            return true;
+        } catch (Exception e) {
+            FileLog.e(TAG, "Failed to verify db", e);
+            return false;
+        } finally {
+            db.endTransaction();
+        }
+    }
+
+    /**
+     * Makes the following changes in the provider DB.
+     *   1. Removes all entries belonging to a managed profile as managed profiles
+     *      cannot be restored.
+     *   2. Marks all entries as restored. The flags are updated during first load or as
+     *      the restored apps get installed.
+     *   3. If the user serial for primary profile is different than that of the previous device,
+     *      update the entries to the new profile id.
+     */
+    private void sanitizeDB(DatabaseHelper helper, SQLiteDatabase db) throws Exception {
+        long oldProfileId = getDefaultProfileId(db);
+        // Delete all entries which do not belong to the main user
+        int itemsDeleted = db.delete(
+                Favorites.TABLE_NAME, "profileId != ?", new String[]{Long.toString(oldProfileId)});
+        if (itemsDeleted > 0) {
+            FileLog.d(TAG, itemsDeleted + " items belonging to a managed profile, were deleted");
+        }
+
+        // Mark all items as restored.
+        ContentValues values = new ContentValues();
+        values.put(Favorites.RESTORED, 1);
+        db.update(Favorites.TABLE_NAME, values, null, null);
+
+        // Mark widgets with appropriate restore flag
+        values.put(Favorites.RESTORED,
+                LauncherAppWidgetInfo.FLAG_ID_NOT_VALID |
+                LauncherAppWidgetInfo.FLAG_PROVIDER_NOT_READY |
+                LauncherAppWidgetInfo.FLAG_UI_NOT_READY);
+        db.update(Favorites.TABLE_NAME, values, "itemType = ?",
+                new String[]{Integer.toString(Favorites.ITEM_TYPE_APPWIDGET)});
+
+        long myProfileId = helper.getDefaultUserSerial();
+        if (Utilities.longCompare(oldProfileId, myProfileId) != 0) {
+            FileLog.d(TAG, "Changing primary user id from " + oldProfileId + " to " + myProfileId);
+            migrateProfileId(db, myProfileId);
+        }
+    }
+
+    /**
+     * Updates profile id of all entries and changes the default value for the column.
+     */
+    protected void migrateProfileId(SQLiteDatabase db, long newProfileId) {
+        // Update existing entries.
+        ContentValues values = new ContentValues();
+        values.put(Favorites.PROFILE_ID, newProfileId);
+        db.update(Favorites.TABLE_NAME, values, null, null);
+
+        // Change default value of the column.
+        db.execSQL("ALTER TABLE favorites RENAME TO favorites_old;");
+        Favorites.addTableToDb(db, newProfileId, false);
+        db.execSQL("INSERT INTO favorites SELECT * FROM favorites_old;");
+        db.execSQL("DROP TABLE favorites_old;");
+    }
+
+    /**
+     * Returns the profile id for used in the favorites table of the provided db.
+     */
+    protected long getDefaultProfileId(SQLiteDatabase db) throws Exception {
+        try (Cursor c = db.rawQuery("PRAGMA table_info (favorites)", null)){
+            int nameIndex = c.getColumnIndex(INFO_COLUMN_NAME);
+            while (c.moveToNext()) {
+                if (Favorites.PROFILE_ID.equals(c.getString(nameIndex))) {
+                    return c.getLong(c.getColumnIndex(INFO_COLUMN_DEFAULT_VALUE));
+                }
+            }
+            throw new InvalidObjectException("Table does not have a profile id column");
+        }
+    }
+}