move to backup helper architecture

add journals to DecoderRing, for backup debugging

Bug: 10778984
Change-Id: I38e93853c05f72468b3800c172b96effc70a63e0

1 files changed, 0 insertions, 1004 deletions

diff --git a/src/com/android/launcher3/LauncherBackupAgent.java b/src/com/android/launcher3/LauncherBackupAgent.java
deleted file mode 100644
index f40238cec..000000000
--- a/src/com/android/launcher3/LauncherBackupAgent.java
+++ /dev/null
@@ -1,1004 +0,0 @@
-/*
- * Copyright (C) 2013 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-package com.android.launcher3;
-
-import com.google.protobuf.nano.InvalidProtocolBufferNanoException;
-import com.google.protobuf.nano.MessageNano;
-
-import com.android.launcher3.LauncherSettings.Favorites;
-import com.android.launcher3.LauncherSettings.WorkspaceScreens;
-import com.android.launcher3.backup.BackupProtos;
-import com.android.launcher3.backup.BackupProtos.CheckedMessage;
-import com.android.launcher3.backup.BackupProtos.Favorite;
-import com.android.launcher3.backup.BackupProtos.Journal;
-import com.android.launcher3.backup.BackupProtos.Key;
-import com.android.launcher3.backup.BackupProtos.Resource;
-import com.android.launcher3.backup.BackupProtos.Screen;
-import com.android.launcher3.backup.BackupProtos.Widget;
-
-import android.app.backup.BackupAgent;
-import android.app.backup.BackupDataInput;
-import android.app.backup.BackupDataOutput;
-import android.app.backup.BackupManager;
-import android.appwidget.AppWidgetManager;
-import android.appwidget.AppWidgetProviderInfo;
-import android.content.ComponentName;
-import android.content.ContentResolver;
-import android.content.Context;
-import android.content.Intent;
-import android.database.Cursor;
-import android.graphics.Bitmap;
-import android.graphics.BitmapFactory;
-import android.graphics.drawable.Drawable;
-import android.os.ParcelFileDescriptor;
-import android.text.TextUtils;
-import android.util.Base64;
-import android.util.Log;
-
-import java.io.ByteArrayOutputStream;
-import java.io.FileInputStream;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.net.URISyntaxException;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Set;
-import java.util.zip.CRC32;
-
-/**
- * Persist the launcher home state across calamities.
- */
-public class LauncherBackupAgent extends BackupAgent {
-
-    private static final String TAG = "LauncherBackupAgent";
-    private static final boolean DEBUG = false;
-
-    private static final int MAX_JOURNAL_SIZE = 1000000;
-
-    /** icons are large, dribble them out */
-    private static final int MAX_ICONS_PER_PASS = 10;
-
-    /** widgets contain previews, which are very large, dribble them out */
-    private static final int MAX_WIDGETS_PER_PASS = 5;
-
-    public static final int IMAGE_COMPRESSION_QUALITY = 75;
-
-    private static final Bitmap.CompressFormat IMAGE_FORMAT =
-            android.graphics.Bitmap.CompressFormat.PNG;
-
-    private static BackupManager sBackupManager;
-
-    private static final String[] FAVORITE_PROJECTION = {
-            Favorites._ID,                     // 0
-            Favorites.MODIFIED,                // 1
-            Favorites.INTENT,                  // 2
-            Favorites.APPWIDGET_PROVIDER,      // 3
-            Favorites.APPWIDGET_ID,            // 4
-            Favorites.CELLX,                   // 5
-            Favorites.CELLY,                   // 6
-            Favorites.CONTAINER,               // 7
-            Favorites.ICON,                    // 8
-            Favorites.ICON_PACKAGE,            // 9
-            Favorites.ICON_RESOURCE,           // 10
-            Favorites.ICON_TYPE,               // 11
-            Favorites.ITEM_TYPE,               // 12
-            Favorites.SCREEN,                  // 13
-            Favorites.SPANX,                   // 14
-            Favorites.SPANY,                   // 15
-            Favorites.TITLE,                   // 16
-    };
-
-    private static final int ID_INDEX = 0;
-    private static final int ID_MODIFIED = 1;
-    private static final int INTENT_INDEX = 2;
-    private static final int APPWIDGET_PROVIDER_INDEX = 3;
-    private static final int APPWIDGET_ID_INDEX = 4;
-    private static final int CELLX_INDEX = 5;
-    private static final int CELLY_INDEX = 6;
-    private static final int CONTAINER_INDEX = 7;
-    private static final int ICON_INDEX = 8;
-    private static final int ICON_PACKAGE_INDEX = 9;
-    private static final int ICON_RESOURCE_INDEX = 10;
-    private static final int ICON_TYPE_INDEX = 11;
-    private static final int ITEM_TYPE_INDEX = 12;
-    private static final int SCREEN_INDEX = 13;
-    private static final int SPANX_INDEX = 14;
-    private static final int SPANY_INDEX = 15;
-    private static final int TITLE_INDEX = 16;
-
-    private static final String[] SCREEN_PROJECTION = {
-            WorkspaceScreens._ID,              // 0
-            WorkspaceScreens.MODIFIED,         // 1
-            WorkspaceScreens.SCREEN_RANK       // 2
-    };
-
-    private static final int SCREEN_RANK_INDEX = 2;
-
-
-    private static final String[] ICON_PROJECTION = {
-            Favorites._ID,                // 0
-            Favorites.MODIFIED,           // 1
-            Favorites.INTENT              // 2
-    };
-
-    private HashMap<ComponentName, AppWidgetProviderInfo> mWidgetMap;
-
-
-    /**
-     * Notify the backup manager that out database is dirty.
-     *
-     * <P>This does not force an immediate backup.
-     *
-     * @param context application context
-     */
-    public static void dataChanged(Context context) {
-        if (sBackupManager == null) {
-            sBackupManager = new BackupManager(context);
-        }
-        sBackupManager.dataChanged();
-    }
-
-    /**
-     * Back up launcher data so we can restore the user's state on a new device.
-     *
-     * <P>The journal is a timestamp and a list of keys that were saved as of that time.
-     *
-     * <P>Keys may come back in any order, so each key/value is one complete row of the database.
-     *
-     * @param oldState notes from the last backup
-     * @param data incremental key/value pairs to persist off-device
-     * @param newState notes for the next backup
-     * @throws IOException
-     */
-    @Override
-    public void onBackup(ParcelFileDescriptor oldState, BackupDataOutput data,
-            ParcelFileDescriptor newState)
-            throws IOException {
-        Log.v(TAG, "onBackup");
-
-        Journal in = readJournal(oldState);
-        Journal out = new Journal();
-
-        long lastBackupTime = in.t;
-        out.t = System.currentTimeMillis();
-        out.rows = 0;
-        out.bytes = 0;
-
-        Log.v(TAG, "lastBackupTime=" + lastBackupTime);
-
-        ArrayList<Key> keys = new ArrayList<Key>();
-        backupFavorites(in, data, out, keys);
-        backupScreens(in, data, out, keys);
-        backupIcons(in, data, out, keys);
-        backupWidgets(in, data, out, keys);
-
-        out.key = keys.toArray(BackupProtos.Key.EMPTY_ARRAY);
-        writeJournal(newState, out);
-        Log.v(TAG, "onBackup: wrote " + out.bytes + "b in " + out.rows + " rows.");
-    }
-
-    /**
-     * Restore home screen from the restored data stream.
-     *
-     * <P>Keys may arrive in any order.
-     *
-     * @param data the key/value pairs from the server
-     * @param versionCode the version of the app that generated the data
-     * @param newState notes for the next backup
-     * @throws IOException
-     */
-    @Override
-    public void onRestore(BackupDataInput data, int versionCode, ParcelFileDescriptor newState)
-            throws IOException {
-        Log.v(TAG, "onRestore");
-        int numRows = 0;
-        Journal out = new Journal();
-
-        ArrayList<Key> keys = new ArrayList<Key>();
-        byte[] buffer = new byte[512];
-        while (data.readNextHeader()) {
-            numRows++;
-            String backupKey = data.getKey();
-            int dataSize = data.getDataSize();
-            if (buffer.length < dataSize) {
-                buffer = new byte[dataSize];
-            }
-            Key key = null;
-            int bytesRead = data.readEntityData(buffer, 0, dataSize);
-            if (DEBUG) {
-                Log.d(TAG, "read " + bytesRead + " of " + dataSize + " available");
-            }
-            try {
-                key = backupKeyToKey(backupKey);
-                switch (key.type) {
-                    case Key.FAVORITE:
-                        restoreFavorite(key, buffer, dataSize, keys);
-                        break;
-
-                    case Key.SCREEN:
-                        restoreScreen(key, buffer, dataSize, keys);
-                        break;
-
-                    case Key.ICON:
-                        restoreIcon(key, buffer, dataSize, keys);
-                        break;
-
-                    case Key.WIDGET:
-                        restoreWidget(key, buffer, dataSize, keys);
-                        break;
-
-                    default:
-                        Log.w(TAG, "unknown restore entity type: " + key.type);
-                        break;
-                }
-            } catch (KeyParsingException e) {
-                Log.w(TAG, "ignoring unparsable backup key: " + backupKey);
-            }
-        }
-
-        // clear the output journal time, to force a full backup to
-        // will catch any changes the restore process might have made
-        out.t = 0;
-        out.key = keys.toArray(BackupProtos.Key.EMPTY_ARRAY);
-        writeJournal(newState, out);
-        Log.v(TAG, "onRestore: read " + numRows + " rows");
-    }
-
-    /**
-     * Write all modified favorites to the data stream.
-     *
-     *
-     * @param in notes from last backup
-     * @param data output stream for key/value pairs
-     * @param out notes about this backup
-     * @param keys keys to mark as clean in the notes for next backup
-     * @throws IOException
-     */
-    private void backupFavorites(Journal in, BackupDataOutput data, Journal out,
-            ArrayList<Key> keys)
-            throws IOException {
-        // read the old ID set
-        Set<String> savedIds = getSavedIdsByType(Key.FAVORITE, in);
-        if (DEBUG) Log.d(TAG, "favorite savedIds.size()=" + savedIds.size());
-
-        // persist things that have changed since the last backup
-        ContentResolver cr = getContentResolver();
-        Cursor cursor = cr.query(Favorites.CONTENT_URI, FAVORITE_PROJECTION,
-                null, null, null);
-        Set<String> currentIds = new HashSet<String>(cursor.getCount());
-        try {
-            cursor.moveToPosition(-1);
-            while(cursor.moveToNext()) {
-                final long id = cursor.getLong(ID_INDEX);
-                final long updateTime = cursor.getLong(ID_MODIFIED);
-                Key key = getKey(Key.FAVORITE, id);
-                keys.add(key);
-                currentIds.add(keyToBackupKey(key));
-                if (updateTime > in.t) {
-                    byte[] blob = packFavorite(cursor);
-                    writeRowToBackup(key, blob, out, data);
-                }
-            }
-        } finally {
-            cursor.close();
-        }
-        if (DEBUG) Log.d(TAG, "favorite currentIds.size()=" + currentIds.size());
-
-        // these IDs must have been deleted
-        savedIds.removeAll(currentIds);
-        out.rows += removeDeletedKeysFromBackup(savedIds, data);
-    }
-
-    /**
-     * Read a favorite from the stream.
-     *
-     * <P>Keys arrive in any order, so screens and containers may not exist yet.
-     *
-     * @param key identifier for the row
-     * @param buffer the serialized proto from the stream, may be larger than dataSize
-     * @param dataSize the size of the proto from the stream
-     * @param keys keys to mark as clean in the notes for next backup
-     */
-    private void restoreFavorite(Key key, byte[] buffer, int dataSize, ArrayList<Key> keys) {
-        Log.v(TAG, "unpacking favorite " + key.id + " (" + dataSize + " bytes)");
-        if (DEBUG) Log.d(TAG, "read (" + buffer.length + "): " +
-                Base64.encodeToString(buffer, 0, dataSize, Base64.NO_WRAP));
-
-        try {
-            Favorite favorite =  unpackFavorite(buffer, 0, dataSize);
-            if (DEBUG) Log.d(TAG, "unpacked " + favorite.itemType);
-        } catch (InvalidProtocolBufferNanoException e) {
-            Log.w(TAG, "failed to decode proto", e);
-        }
-    }
-
-    /**
-     * Write all modified screens to the data stream.
-     *
-     *
-     * @param in notes from last backup
-     * @param data output stream for key/value pairs
-     * @param out notes about this backup
-     * @param keys keys to mark as clean in the notes for next backup
-     * @throws IOException
-     */
-    private void backupScreens(Journal in, BackupDataOutput data, Journal out,
-            ArrayList<Key> keys)
-            throws IOException {
-        // read the old ID set
-        Set<String> savedIds = getSavedIdsByType(Key.SCREEN, in);
-        if (DEBUG) Log.d(TAG, "screen savedIds.size()=" + savedIds.size());
-
-        // persist things that have changed since the last backup
-        ContentResolver cr = getContentResolver();
-        Cursor cursor = cr.query(WorkspaceScreens.CONTENT_URI, SCREEN_PROJECTION,
-                null, null, null);
-        Set<String> currentIds = new HashSet<String>(cursor.getCount());
-        try {
-            cursor.moveToPosition(-1);
-            while(cursor.moveToNext()) {
-                final long id = cursor.getLong(ID_INDEX);
-                final long updateTime = cursor.getLong(ID_MODIFIED);
-                Key key = getKey(Key.SCREEN, id);
-                keys.add(key);
-                currentIds.add(keyToBackupKey(key));
-                if (updateTime > in.t) {
-                    byte[] blob = packScreen(cursor);
-                    writeRowToBackup(key, blob, out, data);
-                }
-            }
-        } finally {
-            cursor.close();
-        }
-        if (DEBUG) Log.d(TAG, "screen currentIds.size()=" + currentIds.size());
-
-        // these IDs must have been deleted
-        savedIds.removeAll(currentIds);
-        out.rows += removeDeletedKeysFromBackup(savedIds, data);
-    }
-
-    /**
-     * Read a screen from the stream.
-     *
-     * <P>Keys arrive in any order, so children of this screen may already exist.
-     *
-     * @param key identifier for the row
-     * @param buffer the serialized proto from the stream, may be larger than dataSize
-     * @param dataSize the size of the proto from the stream
-     * @param keys keys to mark as clean in the notes for next backup
-     */
-    private void restoreScreen(Key key, byte[] buffer, int dataSize, ArrayList<Key> keys) {
-        Log.v(TAG, "unpacking screen " + key.id);
-        if (DEBUG) Log.d(TAG, "read (" + buffer.length + "): " +
-                Base64.encodeToString(buffer, 0, dataSize, Base64.NO_WRAP));
-        try {
-            Screen screen = unpackScreen(buffer, 0, dataSize);
-            if (DEBUG) Log.d(TAG, "unpacked " + screen.rank);
-        } catch (InvalidProtocolBufferNanoException e) {
-            Log.w(TAG, "failed to decode proto", e);
-        }
-    }
-
-    /**
-     * Write all the static icon resources we need to render placeholders
-     * for a package that is not installed.
-     *
-     * @param in notes from last backup
-     * @param data output stream for key/value pairs
-     * @param out notes about this backup
-     * @param keys keys to mark as clean in the notes for next backup
-     * @throws IOException
-     */
-    private void backupIcons(Journal in, BackupDataOutput data, Journal out,
-            ArrayList<Key> keys) throws IOException {
-        // persist icons that haven't been persisted yet
-        final LauncherAppState app = LauncherAppState.getInstanceNoCreate();
-        if (app == null) {
-            dataChanged(this); // try again later
-            if (DEBUG) Log.d(TAG, "Launcher is not initialized, delaying icon backup");
-            return;
-        }
-        final ContentResolver cr = getContentResolver();
-        final IconCache iconCache = app.getIconCache();
-        final int dpi = getResources().getDisplayMetrics().densityDpi;
-
-        // read the old ID set
-        Set<String> savedIds = getSavedIdsByType(Key.ICON, in);
-        if (DEBUG) Log.d(TAG, "icon savedIds.size()=" + savedIds.size());
-
-        int startRows = out.rows;
-        if (DEBUG) Log.d(TAG, "starting here: " + startRows);
-        String where = Favorites.ITEM_TYPE + "=" + Favorites.ITEM_TYPE_APPLICATION;
-        Cursor cursor = cr.query(Favorites.CONTENT_URI, FAVORITE_PROJECTION,
-                where, null, null);
-        Set<String> currentIds = new HashSet<String>(cursor.getCount());
-        try {
-            cursor.moveToPosition(-1);
-            while(cursor.moveToNext()) {
-                final long id = cursor.getLong(ID_INDEX);
-                final String intentDescription = cursor.getString(INTENT_INDEX);
-                try {
-                    Intent intent = Intent.parseUri(intentDescription, 0);
-                    ComponentName cn = intent.getComponent();
-                    Key key = null;
-                    String backupKey = null;
-                    if (cn != null) {
-                        key = getKey(Key.ICON, cn.flattenToShortString());
-                        backupKey = keyToBackupKey(key);
-                        currentIds.add(backupKey);
-                    } else {
-                        Log.w(TAG, "empty intent on application favorite: " + id);
-                    }
-                    if (savedIds.contains(backupKey)) {
-                        if (DEBUG) Log.d(TAG, "already saved icon " + backupKey);
-
-                        // remember that we already backed this up previously
-                        keys.add(key);
-                    } else if (backupKey != null) {
-                        if (DEBUG) Log.d(TAG, "I can count this high: " + out.rows);
-                        if ((out.rows - startRows) < MAX_ICONS_PER_PASS) {
-                            if (DEBUG) Log.d(TAG, "saving icon " + backupKey);
-                            Bitmap icon = iconCache.getIcon(intent);
-                            keys.add(key);
-                            if (icon != null && !iconCache.isDefaultIcon(icon)) {
-                                byte[] blob = packIcon(dpi, icon);
-                                writeRowToBackup(key, blob, out, data);
-                            }
-                        } else {
-                            if (DEBUG) Log.d(TAG, "scheduling another run for icon " + backupKey);
-                            // too many icons for this pass, request another.
-                            dataChanged(this);
-                        }
-                    }
-                } catch (URISyntaxException e) {
-                    Log.w(TAG, "invalid URI on application favorite: " + id);
-                } catch (IOException e) {
-                    Log.w(TAG, "unable to save application icon for favorite: " + id);
-                }
-
-            }
-        } finally {
-            cursor.close();
-        }
-        if (DEBUG) Log.d(TAG, "icon currentIds.size()=" + currentIds.size());
-
-        // these IDs must have been deleted
-        savedIds.removeAll(currentIds);
-        out.rows += removeDeletedKeysFromBackup(savedIds, data);
-    }
-
-    /**
-     * Read an icon from the stream.
-     *
-     * <P>Keys arrive in any order, so shortcuts that use this icon may already exist.
-     *
-     * @param key identifier for the row
-     * @param buffer the serialized proto from the stream, may be larger than dataSize
-     * @param dataSize the size of the proto from the stream
-     * @param keys keys to mark as clean in the notes for next backup
-     */
-    private void restoreIcon(Key key, byte[] buffer, int dataSize, ArrayList<Key> keys) {
-        Log.v(TAG, "unpacking icon " + key.id);
-        if (DEBUG) Log.d(TAG, "read (" + buffer.length + "): " +
-                Base64.encodeToString(buffer, 0, dataSize, Base64.NO_WRAP));
-        try {
-            Resource res = unpackIcon(buffer, 0, dataSize);
-            if (DEBUG) Log.d(TAG, "unpacked " + res.dpi);
-            if (DEBUG) Log.d(TAG, "read " +
-                    Base64.encodeToString(res.data, 0, res.data.length,
-                            Base64.NO_WRAP));
-            Bitmap icon = BitmapFactory.decodeByteArray(res.data, 0, res.data.length);
-            if (icon == null) {
-                Log.w(TAG, "failed to unpack icon for " + key.name);
-            }
-        } catch (InvalidProtocolBufferNanoException e) {
-            Log.w(TAG, "failed to decode proto", e);
-        }
-    }
-
-    /**
-     * Write all the static widget resources we need to render placeholders
-     * for a package that is not installed.
-     *
-     * @param in notes from last backup
-     * @param data output stream for key/value pairs
-     * @param out notes about this backup
-     * @param keys keys to mark as clean in the notes for next backup
-     * @throws IOException
-     */
-    private void backupWidgets(Journal in, BackupDataOutput data, Journal out,
-            ArrayList<Key> keys) throws IOException {
-        // persist static widget info that hasn't been persisted yet
-        final LauncherAppState appState = LauncherAppState.getInstanceNoCreate();
-        if (appState == null) {
-            dataChanged(this); // try again later
-            if (DEBUG) Log.d(TAG, "Launcher is not initialized, delaying widget backup");
-            return;
-        }
-        final ContentResolver cr = getContentResolver();
-        final WidgetPreviewLoader previewLoader = new WidgetPreviewLoader(this);
-        final PagedViewCellLayout widgetSpacingLayout = new PagedViewCellLayout(this);
-        final IconCache iconCache = appState.getIconCache();
-        final int dpi = getResources().getDisplayMetrics().densityDpi;
-        final DeviceProfile profile = appState.getDynamicGrid().getDeviceProfile();
-        if (DEBUG) Log.d(TAG, "cellWidthPx: " + profile.cellWidthPx);
-
-        // read the old ID set
-        Set<String> savedIds = getSavedIdsByType(Key.WIDGET, in);
-        if (DEBUG) Log.d(TAG, "widgets savedIds.size()=" + savedIds.size());
-
-        int startRows = out.rows;
-        if (DEBUG) Log.d(TAG, "starting here: " + startRows);
-        String where = Favorites.ITEM_TYPE + "=" + Favorites.ITEM_TYPE_APPWIDGET;
-        Cursor cursor = cr.query(Favorites.CONTENT_URI, FAVORITE_PROJECTION,
-                where, null, null);
-        Set<String> currentIds = new HashSet<String>(cursor.getCount());
-        try {
-            cursor.moveToPosition(-1);
-            while(cursor.moveToNext()) {
-                final long id = cursor.getLong(ID_INDEX);
-                final String providerName = cursor.getString(APPWIDGET_PROVIDER_INDEX);
-                final int spanX = cursor.getInt(SPANX_INDEX);
-                final int spanY = cursor.getInt(SPANY_INDEX);
-                final ComponentName provider = ComponentName.unflattenFromString(providerName);
-                Key key = null;
-                String backupKey = null;
-                if (provider != null) {
-                    key = getKey(Key.WIDGET, providerName);
-                    backupKey = keyToBackupKey(key);
-                    currentIds.add(backupKey);
-                } else {
-                    Log.w(TAG, "empty intent on appwidget: " + id);
-                }
-                if (savedIds.contains(backupKey)) {
-                    if (DEBUG) Log.d(TAG, "already saved widget " + backupKey);
-
-                    // remember that we already backed this up previously
-                    keys.add(key);
-                } else if (backupKey != null) {
-                    if (DEBUG) Log.d(TAG, "I can count this high: " + out.rows);
-                    if ((out.rows - startRows) < MAX_WIDGETS_PER_PASS) {
-                        if (DEBUG) Log.d(TAG, "saving widget " + backupKey);
-                        previewLoader.setPreviewSize(spanX * profile.cellWidthPx,
-                                spanY * profile.cellHeightPx, widgetSpacingLayout);
-                        byte[] blob = packWidget(dpi, previewLoader, iconCache, provider);
-                        keys.add(key);
-                        writeRowToBackup(key, blob, out, data);
-
-                    } else {
-                        if (DEBUG) Log.d(TAG, "scheduling another run for widget " + backupKey);
-                        // too many widgets for this pass, request another.
-                        dataChanged(this);
-                    }
-                }
-            }
-        } finally {
-            cursor.close();
-        }
-        if (DEBUG) Log.d(TAG, "widget currentIds.size()=" + currentIds.size());
-
-        // these IDs must have been deleted
-        savedIds.removeAll(currentIds);
-        out.rows += removeDeletedKeysFromBackup(savedIds, data);
-    }
-
-    /**
-     * Read a widget from the stream.
-     *
-     * <P>Keys arrive in any order, so widgets that use this data may already exist.
-     *
-     * @param key identifier for the row
-     * @param buffer the serialized proto from the stream, may be larger than dataSize
-     * @param dataSize the size of the proto from the stream
-     * @param keys keys to mark as clean in the notes for next backup
-     */
-    private void restoreWidget(Key key, byte[] buffer, int dataSize, ArrayList<Key> keys) {
-        Log.v(TAG, "unpacking widget " + key.id);
-        if (DEBUG) Log.d(TAG, "read (" + buffer.length + "): " +
-                Base64.encodeToString(buffer, 0, dataSize, Base64.NO_WRAP));
-        try {
-            Widget widget = unpackWidget(buffer, 0, dataSize);
-            if (DEBUG) Log.d(TAG, "unpacked " + widget.provider);
-            if (widget.icon.data != null)  {
-                Bitmap icon = BitmapFactory
-                        .decodeByteArray(widget.icon.data, 0, widget.icon.data.length);
-                if (icon == null) {
-                    Log.w(TAG, "failed to unpack widget icon for " + key.name);
-                }
-            }
-        } catch (InvalidProtocolBufferNanoException e) {
-            Log.w(TAG, "failed to decode proto", e);
-        }
-    }
-
-    /** create a new key, with an integer ID.
-     *
-     * <P> Keys contain their own checksum instead of using
-     * the heavy-weight CheckedMessage wrapper.
-     */
-    private Key getKey(int type, long id) {
-        Key key = new Key();
-        key.type = type;
-        key.id = id;
-        key.checksum = checkKey(key);
-        return key;
-    }
-
-    /** create a new key for a named object.
-     *
-     * <P> Keys contain their own checksum instead of using
-     * the heavy-weight CheckedMessage wrapper.
-     */
-    private Key getKey(int type, String name) {
-        Key key = new Key();
-        key.type = type;
-        key.name = name;
-        key.checksum = checkKey(key);
-        return key;
-    }
-
-    /** keys need to be strings, serialize and encode. */
-    private String keyToBackupKey(Key key) {
-        return Base64.encodeToString(Key.toByteArray(key), Base64.NO_WRAP);
-    }
-
-    /** keys need to be strings, decode and parse. */
-    private Key backupKeyToKey(String backupKey) throws KeyParsingException {
-        try {
-            Key key = Key.parseFrom(Base64.decode(backupKey, Base64.DEFAULT));
-            if (key.checksum != checkKey(key)) {
-                key = null;
-                throw new KeyParsingException("invalid key read from stream" + backupKey);
-            }
-            return key;
-        } catch (InvalidProtocolBufferNanoException e) {
-            throw new KeyParsingException(e);
-        } catch (IllegalArgumentException e) {
-            throw new KeyParsingException(e);
-        }
-    }
-
-    private String getKeyName(Key key) {
-        if (TextUtils.isEmpty(key.name)) {
-            return Long.toString(key.id);
-        } else {
-            return key.name;
-        }
-
-    }
-
-    private String geKeyType(Key key) {
-        switch (key.type) {
-            case Key.FAVORITE:
-                return "favorite";
-            case Key.SCREEN:
-                return "screen";
-            case Key.ICON:
-                return "icon";
-            case Key.WIDGET:
-                return "widget";
-            default:
-                return "anonymous";
-        }
-    }
-
-    /** Compute the checksum over the important bits of a key. */
-    private long checkKey(Key key) {
-        CRC32 checksum = new CRC32();
-        checksum.update(key.type);
-        checksum.update((int) (key.id & 0xffff));
-        checksum.update((int) ((key.id >> 32) & 0xffff));
-        if (!TextUtils.isEmpty(key.name)) {
-            checksum.update(key.name.getBytes());
-        }
-        return checksum.getValue();
-    }
-
-    /** Serialize a Favorite for persistence, including a checksum wrapper. */
-    private byte[] packFavorite(Cursor c) {
-        Favorite favorite = new Favorite();
-        favorite.id = c.getLong(ID_INDEX);
-        favorite.screen = c.getInt(SCREEN_INDEX);
-        favorite.container = c.getInt(CONTAINER_INDEX);
-        favorite.cellX = c.getInt(CELLX_INDEX);
-        favorite.cellY = c.getInt(CELLY_INDEX);
-        favorite.spanX = c.getInt(SPANX_INDEX);
-        favorite.spanY = c.getInt(SPANY_INDEX);
-        favorite.iconType = c.getInt(ICON_TYPE_INDEX);
-        if (favorite.iconType == Favorites.ICON_TYPE_RESOURCE) {
-            String iconPackage = c.getString(ICON_PACKAGE_INDEX);
-            if (!TextUtils.isEmpty(iconPackage)) {
-                favorite.iconPackage = iconPackage;
-            }
-            String iconResource = c.getString(ICON_RESOURCE_INDEX);
-            if (!TextUtils.isEmpty(iconResource)) {
-                favorite.iconResource = iconResource;
-            }
-        }
-        if (favorite.iconType == Favorites.ICON_TYPE_BITMAP) {
-            byte[] blob = c.getBlob(ICON_INDEX);
-            if (blob != null && blob.length > 0) {
-                favorite.icon = blob;
-            }
-        }
-        String title = c.getString(TITLE_INDEX);
-        if (!TextUtils.isEmpty(title)) {
-            favorite.title = title;
-        }
-        String intent = c.getString(INTENT_INDEX);
-        if (!TextUtils.isEmpty(intent)) {
-            favorite.intent = intent;
-        }
-        favorite.itemType = c.getInt(ITEM_TYPE_INDEX);
-        if (favorite.itemType == Favorites.ITEM_TYPE_APPWIDGET) {
-            favorite.appWidgetId = c.getInt(APPWIDGET_ID_INDEX);
-            String appWidgetProvider = c.getString(APPWIDGET_PROVIDER_INDEX);
-            if (!TextUtils.isEmpty(appWidgetProvider)) {
-                favorite.appWidgetProvider = appWidgetProvider;
-            }
-        }
-
-        return writeCheckedBytes(favorite);
-    }
-
-    /** Deserialize a Favorite from persistence, after verifying checksum wrapper. */
-    private Favorite unpackFavorite(byte[] buffer, int offset, int dataSize)
-            throws InvalidProtocolBufferNanoException {
-        Favorite favorite = new Favorite();
-        MessageNano.mergeFrom(favorite, readCheckedBytes(buffer, offset, dataSize));
-        return favorite;
-    }
-
-    /** Serialize a Screen for persistence, including a checksum wrapper. */
-    private byte[] packScreen(Cursor c) {
-        Screen screen = new Screen();
-        screen.id = c.getLong(ID_INDEX);
-        screen.rank = c.getInt(SCREEN_RANK_INDEX);
-
-        return writeCheckedBytes(screen);
-    }
-
-    /** Deserialize a Screen from persistence, after verifying checksum wrapper. */
-    private Screen unpackScreen(byte[] buffer, int offset, int dataSize)
-            throws InvalidProtocolBufferNanoException {
-        Screen screen = new Screen();
-        MessageNano.mergeFrom(screen, readCheckedBytes(buffer, offset, dataSize));
-        return screen;
-    }
-
-    /** Serialize an icon Resource for persistence, including a checksum wrapper. */
-    private byte[] packIcon(int dpi, Bitmap icon) {
-        Resource res = new Resource();
-        res.dpi = dpi;
-        ByteArrayOutputStream os = new ByteArrayOutputStream();
-        if (icon.compress(IMAGE_FORMAT, IMAGE_COMPRESSION_QUALITY, os)) {
-            res.data = os.toByteArray();
-        }
-        return writeCheckedBytes(res);
-    }
-
-    /** Deserialize an icon resource from persistence, after verifying checksum wrapper. */
-    private Resource unpackIcon(byte[] buffer, int offset, int dataSize)
-            throws InvalidProtocolBufferNanoException {
-        Resource res = new Resource();
-        MessageNano.mergeFrom(res, readCheckedBytes(buffer, offset, dataSize));
-        return res;
-    }
-
-    /** Serialize a widget for persistence, including a checksum wrapper. */
-    private byte[] packWidget(int dpi, WidgetPreviewLoader previewLoader, IconCache iconCache,
-            ComponentName provider) {
-        final AppWidgetProviderInfo info = findAppWidgetProviderInfo(provider);
-        Widget widget = new Widget();
-        widget.provider = provider.flattenToShortString();
-        widget.label = info.label;
-        widget.configure = info.configure != null;
-        if (info.icon != 0) {
-            widget.icon = new Resource();
-            Drawable fullResIcon = iconCache.getFullResIcon(provider.getPackageName(), info.icon);
-            Bitmap icon = Utilities.createIconBitmap(fullResIcon, this);
-            ByteArrayOutputStream os = new ByteArrayOutputStream();
-            if (icon.compress(IMAGE_FORMAT, IMAGE_COMPRESSION_QUALITY, os)) {
-                widget.icon.data = os.toByteArray();
-                widget.icon.dpi = dpi;
-            }
-        }
-        if (info.previewImage != 0) {
-            widget.preview = new Resource();
-            Bitmap preview = previewLoader.generateWidgetPreview(info, null);
-            ByteArrayOutputStream os = new ByteArrayOutputStream();
-            if (preview.compress(IMAGE_FORMAT, IMAGE_COMPRESSION_QUALITY, os)) {
-                widget.preview.data = os.toByteArray();
-                widget.preview.dpi = dpi;
-            }
-        }
-        return writeCheckedBytes(widget);
-    }
-
-    /** Deserialize a widget from persistence, after verifying checksum wrapper. */
-    private Widget unpackWidget(byte[] buffer, int offset, int dataSize)
-            throws InvalidProtocolBufferNanoException {
-        Widget widget = new Widget();
-        MessageNano.mergeFrom(widget, readCheckedBytes(buffer, offset, dataSize));
-        return widget;
-    }
-
-    /**
-     * Read the old journal from the input file.
-     *
-     * In the event of any error, just pretend we didn't have a journal,
-     * in that case, do a full backup.
-     *
-     * @param oldState the read-0only file descriptor pointing to the old journal
-     * @return a Journal protocol bugffer
-     */
-    private Journal readJournal(ParcelFileDescriptor oldState) {
-        int fileSize = (int) oldState.getStatSize();
-        int remaining = fileSize;
-        byte[] buffer = null;
-        Journal journal = new Journal();
-        if (remaining < MAX_JOURNAL_SIZE) {
-            FileInputStream inStream = new FileInputStream(oldState.getFileDescriptor());
-            int offset = 0;
-
-            buffer = new byte[remaining];
-            while (remaining > 0) {
-                int bytesRead = 0;
-                try {
-                    bytesRead = inStream.read(buffer, offset, remaining);
-                } catch (IOException e) {
-                    Log.w(TAG, "failed to read the journal", e);
-                    buffer = null;
-                    remaining = 0;
-                }
-                if (bytesRead > 0) {
-                    remaining -= bytesRead;
-                } else {
-                    // act like there is not journal
-                    Log.w(TAG, "failed to read the journal");
-                    buffer = null;
-                    remaining = 0;
-                }
-            }
-
-            if (buffer != null) {
-                try {
-                    MessageNano.mergeFrom(journal, readCheckedBytes(buffer, 0, fileSize));
-                } catch (InvalidProtocolBufferNanoException e) {
-                    Log.d(TAG, "failed to read the journal", e);
-                    journal.clear();
-                }
-            }
-
-            try {
-                inStream.close();
-            } catch (IOException e) {
-                Log.d(TAG, "failed to close the journal", e);
-            }
-        }
-        return journal;
-    }
-
-    private void writeRowToBackup(Key key, byte[] blob, Journal out,
-            BackupDataOutput data) throws IOException {
-        String backupKey = keyToBackupKey(key);
-        data.writeEntityHeader(backupKey, blob.length);
-        data.writeEntityData(blob, blob.length);
-        out.rows++;
-        out.bytes += blob.length;
-        Log.v(TAG, "saving " + geKeyType(key) + " " + backupKey + ": " +
-                getKeyName(key) + "/" + blob.length);
-        if(DEBUG) {
-            String encoded = Base64.encodeToString(blob, 0, blob.length, Base64.NO_WRAP);
-            final int chunkSize = 1024;
-            for (int offset = 0; offset < encoded.length(); offset += chunkSize) {
-                int end = offset + chunkSize;
-                end = Math.min(end, encoded.length());
-                Log.d(TAG, "wrote " + encoded.substring(offset, end));
-            }
-        }
-    }
-
-    private Set<String> getSavedIdsByType(int type, Journal in) {
-        Set<String> savedIds = new HashSet<String>();
-        for(int i = 0; i < in.key.length; i++) {
-            Key key = in.key[i];
-            if (key.type == type) {
-                savedIds.add(keyToBackupKey(key));
-            }
-        }
-        return savedIds;
-    }
-
-    private int removeDeletedKeysFromBackup(Set<String> deletedIds, BackupDataOutput data)
-            throws IOException {
-        int rows = 0;
-        for(String deleted: deletedIds) {
-            Log.v(TAG, "dropping icon " + deleted);
-            data.writeEntityHeader(deleted, -1);
-            rows++;
-        }
-        return rows;
-    }
-
-    /**
-     * Write the new journal to the output file.
-     *
-     * In the event of any error, just pretend we didn't have a journal,
-     * in that case, do a full backup.
-
-     * @param newState the write-only file descriptor pointing to the new journal
-     * @param journal a Journal protocol buffer
-     */
-    private void writeJournal(ParcelFileDescriptor newState, Journal journal) {
-        FileOutputStream outStream = null;
-        try {
-            outStream = new FileOutputStream(newState.getFileDescriptor());
-            outStream.write(writeCheckedBytes(journal));
-            outStream.close();
-        } catch (IOException e) {
-            Log.d(TAG, "failed to write backup journal", e);
-        }
-    }
-
-    /** Wrap a proto in a CheckedMessage and compute the checksum. */
-    private byte[] writeCheckedBytes(MessageNano proto) {
-        CheckedMessage wrapper = new CheckedMessage();
-        wrapper.payload = MessageNano.toByteArray(proto);
-        CRC32 checksum = new CRC32();
-        checksum.update(wrapper.payload);
-        wrapper.checksum = checksum.getValue();
-        return MessageNano.toByteArray(wrapper);
-    }
-
-    /** Unwrap a proto message from a CheckedMessage, verifying the checksum. */
-    private byte[] readCheckedBytes(byte[] buffer, int offset, int dataSize)
-            throws InvalidProtocolBufferNanoException {
-        CheckedMessage wrapper = new CheckedMessage();
-        MessageNano.mergeFrom(wrapper, buffer, offset, dataSize);
-        CRC32 checksum = new CRC32();
-        checksum.update(wrapper.payload);
-        if (wrapper.checksum != checksum.getValue()) {
-            throw new InvalidProtocolBufferNanoException("checksum does not match");
-        }
-        return wrapper.payload;
-    }
-
-    private AppWidgetProviderInfo findAppWidgetProviderInfo(ComponentName component) {
-        if (mWidgetMap == null) {
-            List<AppWidgetProviderInfo> widgets =
-                    AppWidgetManager.getInstance(this).getInstalledProviders();
-            mWidgetMap = new HashMap<ComponentName, AppWidgetProviderInfo>(widgets.size());
-            for (AppWidgetProviderInfo info : widgets) {
-                mWidgetMap.put(info.provider, info);
-            }
-        }
-        return mWidgetMap.get(component);
-    }
-
-    private class KeyParsingException extends Throwable {
-        private KeyParsingException(Throwable cause) {
-            super(cause);
-        }
-
-        public KeyParsingException(String reason) {
-            super(reason);
-        }
-    }
-}