Merge "Recents backup helper" into lmp-mr1-dev

core/java/android/app/backup/RecentsBackupHelper.java

@@ -0,0 +1,114 @@
+package android.app.backup;
+
+import android.content.Context;
+import android.os.Environment;
+import android.os.ParcelFileDescriptor;
+import android.util.Slog;
+
+import java.io.File;
+
+/**
+ * Helper for saving/restoring 'recent tasks' infrastructure.
+ * @hide
+ */
+public class RecentsBackupHelper implements BackupHelper {
+    private static final String TAG = "RecentsBackup";
+    private static final boolean DEBUG = false;
+
+    // This must match TaskPersister.TASKS_DIRNAME, but that class is not accessible from here
+    private static final String RECENTS_TASK_DIR = "recent_tasks";
+
+    // Must match TaskPersister.IMAGES_DIRNAME, as above
+    private static final String RECENTS_IMAGE_DIR = "recent_images";
+
+    // At restore time, tasks/thumbnails are placed in these directories alongside
+    // the "live" recents dirs named above.
+    private static final String RECENTS_TASK_RESTORE_DIR = "restored_" + RECENTS_TASK_DIR;
+    private static final String RECENTS_IMAGE_RESTORE_DIR = "restored_" + RECENTS_IMAGE_DIR;
+
+    // Prefixes for tagging the two kinds of recents backup records that we might generate
+    private static final String RECENTS_TASK_KEY = "task:";
+    private static final String RECENTS_IMAGE_KEY = "image:";
+
+    FileBackupHelperBase mTaskFileHelper;
+
+    final File mSystemDir;
+    final File mTasksDir;
+    final File mRestoredTasksDir;
+    final File mRestoredImagesDir;
+    final String[] mRecentFiles;
+    final String[] mRecentKeys;
+
+    /**
+     * @param context The agent context in which this helper instance will run
+     */
+    public RecentsBackupHelper(Context context) {
+        mTaskFileHelper = new FileBackupHelperBase(context);
+
+        mSystemDir = new File(Environment.getDataDirectory(), "system");
+        mTasksDir = new File(mSystemDir, RECENTS_TASK_DIR);
+        mRestoredTasksDir = new File(mSystemDir, RECENTS_TASK_RESTORE_DIR);
+        mRestoredImagesDir = new File(mSystemDir, RECENTS_IMAGE_RESTORE_DIR);
+
+        // Currently we back up only the recent-task descriptions, not the thumbnails
+        File[] recentFiles = mTasksDir.listFiles();
+        if (recentFiles != null) {
+            // We explicitly proceed even if this is a zero-size array
+            final int N = recentFiles.length;
+            mRecentKeys = new String[N];
+            mRecentFiles = new String[N];
+            if (DEBUG) {
+                Slog.i(TAG, "Identifying recents for backup: " + N);
+            }
+            for (int i = 0; i < N; i++) {
+                mRecentKeys[i] = new String(RECENTS_TASK_KEY + recentFiles[i].getName());
+                mRecentFiles[i] = recentFiles[i].getAbsolutePath();
+                if (DEBUG) {
+                    Slog.i(TAG, "   " + mRecentKeys[i]);
+                }
+            }
+        } else {
+            mRecentFiles = mRecentKeys = new String[0];
+        }
+    }
+
+    /**
+     * Task-file key:  RECENTS_TASK_KEY + leaf filename
+     * Thumbnail-file key: RECENTS_IMAGE_KEY + leaf filename
+     */
+    @Override
+    public void performBackup(ParcelFileDescriptor oldState, BackupDataOutput data,
+            ParcelFileDescriptor newState) {
+        FileBackupHelperBase.performBackup_checked(oldState, data, newState,
+                mRecentFiles, mRecentKeys);
+    }
+
+    @Override
+    public void restoreEntity(BackupDataInputStream data) {
+        final String key = data.getKey();
+        File output = null;
+        if (key.startsWith(RECENTS_TASK_KEY)) {
+            String name = key.substring(RECENTS_TASK_KEY.length());
+            output = new File(mRestoredTasksDir, name);
+            mRestoredTasksDir.mkdirs();
+        } else if (key.startsWith(RECENTS_IMAGE_KEY)) {
+            String name = key.substring(RECENTS_IMAGE_KEY.length());
+            output = new File(mRestoredImagesDir, name);
+            mRestoredImagesDir.mkdirs();
+        }
+
+        if (output != null) {
+            if (DEBUG) {
+                Slog.i(TAG, "Restoring key='"
+                        + key + "' to " + output.getAbsolutePath());
+            }
+            mTaskFileHelper.writeFile(output, data);
+        }
+    }
+
+    @Override
+    public void writeNewStateDescription(ParcelFileDescriptor newState) {
+        mTaskFileHelper.writeNewStateDescription(newState);
+    }
+
+}

core/java/com/android/server/backup/SystemBackupAgent.java

@@ -23,6 +23,7 @@ import android.app.backup.BackupDataOutput;
 import android.app.backup.BackupAgentHelper;
 import android.app.backup.FullBackup;
 import android.app.backup.FullBackupDataOutput;
+import android.app.backup.RecentsBackupHelper;
 import android.app.backup.WallpaperBackupHelper;
 import android.content.Context;
 import android.os.Environment;
@@ -83,6 +84,8 @@ public class SystemBackupAgent extends BackupAgentHelper {
             }
         }
         addHelper("wallpaper", new WallpaperBackupHelper(SystemBackupAgent.this, files, keys));
+        addHelper("recents", new RecentsBackupHelper(SystemBackupAgent.this));
+
         super.onBackup(oldState, data, newState);
     }
 
@@ -113,6 +116,7 @@ public class SystemBackupAgent extends BackupAgentHelper {
         addHelper("system_files", new WallpaperBackupHelper(SystemBackupAgent.this,
                 new String[] { WALLPAPER_IMAGE },
                 new String[] { WALLPAPER_IMAGE_KEY} ));
+        addHelper("recents", new RecentsBackupHelper(SystemBackupAgent.this));
 
         try {
             super.onRestore(data, appVersionCode, newState);

services/core/java/com/android/server/am/TaskPersister.java

@@ -63,6 +63,12 @@ public class TaskPersister {
     private static final String IMAGES_DIRNAME = "recent_images";
     static final String IMAGE_EXTENSION = ".png";
 
+    // Directory where restored historical task XML/PNG files are placed.  This directory
+    // contains subdirs named after TASKS_DIRNAME and IMAGES_DIRNAME mirroring the
+    // ancestral device's dataset.  This needs to match the RECENTS_TASK_RESTORE_DIR
+    // value in RecentsBackupHelper.
+    private static final String RESTORED_TASKS = "restored_" + TASKS_DIRNAME;
+
     private static final String TAG_TASK = "task";
 
     static File sImagesDir;