commit e0129b3c672f5555deb75366b1a7159f41737874
author Craig Mautner <cmautner@google.com> Sun May 25 16:41:09 2014 -0700
committer Craig Mautner <cmautner@google.com> Tue May 27 06:56:44 2014 -0700
tree 28ec9d3f07aa97e03403f67eef8dfe2bbf710ef8
parent 49a6e1b3213a6e9f06a3562c69f2878b120c5fb5

Add more error checking to xml restore

Bad files and OS updates can cause the restore to throw an NPE.
Rather than bring down the server process over this, just delete
the persistent file and keep going.

Fixes bug 15219594.

Change-Id: Id9cd39988ff93a26def036a05c46209364f2a4c0

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

diff --git a/services/core/java/com/android/server/am/TaskPersister.java b/services/core/java/com/android/server/am/TaskPersister.java
index ba3f2fe..3bfaca9 100644
--- a/services/core/java/com/android/server/am/TaskPersister.java
+++ b/services/core/java/com/android/server/am/TaskPersister.java
@@ -155,6 +155,7 @@
             File taskFile = recentFiles[taskNdx];
             if (DEBUG) Slog.d(TAG, "restoreTasksLocked: taskFile=" + taskFile.getName());
             BufferedReader reader = null;
+            boolean deleteFile = false;
             try {
                 reader = new BufferedReader(new FileReader(taskFile));
                 final XmlPullParser in = Xml.newPullParser();
@@ -183,10 +184,9 @@
                     }
                     XmlUtils.skipCurrentTag(in);
                 }
-            } catch (IOException e) {
-                Slog.e(TAG, "Unable to parse " + taskFile + ". Error " + e);
-            } catch (XmlPullParserException e) {
-                Slog.e(TAG, "Unable to parse " + taskFile + ". Error " + e);
+            } catch (Exception e) {
+                Slog.wtf(TAG, "Unable to parse " + taskFile + ". Error " + e);
+                deleteFile = true;
             } finally {
                 if (reader != null) {
                     try {
@@ -194,6 +194,9 @@
                     } catch (IOException e) {
                     }
                 }
+                if (!DEBUG && deleteFile) {
+                    taskFile.delete();
+                }
             }
         }
 
@@ -220,7 +223,7 @@
         return new ArrayList<TaskRecord>(Arrays.asList(tasksArray));
     }
 
-    private void removeObsoleteFiles(ArraySet<Integer> persistentTaskIds, File[] files) {
+    private static void removeObsoleteFiles(ArraySet<Integer> persistentTaskIds, File[] files) {
         for (int fileNdx = 0; fileNdx < files.length; ++fileNdx) {
             File file = files[fileNdx];
             String filename = file.getName();
@@ -285,8 +288,7 @@
                 synchronized(mService) {
                     final ArrayList<TaskRecord> tasks = mService.mRecentTasks;
                     persistentTaskIds.clear();
-                    int taskNdx;
-                    for (taskNdx = tasks.size() - 1; taskNdx >= 0; --taskNdx) {
+                    for (int taskNdx = tasks.size() - 1; taskNdx >= 0; --taskNdx) {
                         task = tasks.get(taskNdx);
                         if (DEBUG) Slog.d(TAG, "LazyTaskWriter: task=" + task + " persistable=" +
                                 task.isPersistable + " needsPersisting=" + task.needsPersisting);