[Sync] Erase sync DB when corrupted

sync/syncable/directory.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "sync/syncable/directory.h"
 
 #include <algorithm>
 #include <iterator>
 
 #include "base/base64.h"
@@ skipping 93 matching lines @@
 
 Directory::Directory(
     DirectoryBackingStore* store,
     UnrecoverableErrorHandler* unrecoverable_error_handler,
     ReportUnrecoverableErrorFunction report_unrecoverable_error_function,
     NigoriHandler* nigori_handler,
     Cryptographer* cryptographer)
     : kernel_(NULL),
       store_(store),
       unrecoverable_error_handler_(unrecoverable_error_handler),
-      report_unrecoverable_error_function_(
-          report_unrecoverable_error_function),
+      report_unrecoverable_error_function_(report_unrecoverable_error_function),
       unrecoverable_error_set_(false),
       nigori_handler_(nigori_handler),
       cryptographer_(cryptographer),
-      invariant_check_level_(VERIFY_CHANGES) {
+      invariant_check_level_(VERIFY_CHANGES),
+      weak_ptr_factory_(this) {
 }
 
 Directory::~Directory() {
   Close();
 }
 
 DirOpenResult Directory::Open(
     const string& name,
     DirectoryChangeDelegate* delegate,
     const WeakHandle<TransactionObserver>& transaction_observer) {
@@ skipping 71 matching lines @@
 
   // Write back the share info to reserve some space in 'next_id'.  This will
   // prevent local ID reuse in the case of an early crash.  See the comments in
   // TakeSnapshotForSaveChanges() or crbug.com/142987 for more information.
   kernel_->info_status = KERNEL_SHARE_INFO_DIRTY;
 
   kernel_->metahandles_to_purge.swap(metahandles_to_purge);
   if (!SaveChanges())
     return FAILED_INITIAL_WRITE;
 
+  // Now that we've successfully opened the store, install an error handler to
+  // deal with catastrophic errors that may occur later on. Use a weak pointer
+  // because we cannot guarantee that this Directory will outlive the Closure.
+  store_->SetCatastrophicErrorHandler(base::Bind(
+      &Directory::OnCatastrophicError, weak_ptr_factory_.GetWeakPtr()));
+
   return OPENED;
 }
 
 DeleteJournal* Directory::delete_journal() {
   DCHECK(delete_journal_.get());
   return delete_journal_.get();
 }
 
 void Directory::Close() {
   store_.reset();
@@ skipping 1326 matching lines @@
   // server.  To avoid re-uploading the same attachment mulitple times, we
   // remove any ids known to be on the server from the id_set we are about to
   // return.
   //
   // TODO(maniscalco): Eliminate redundant metadata storage (bug 415203).
   std::set_difference(not_on_server_id_set.begin(), not_on_server_id_set.end(),
                       on_server_id_set.begin(), on_server_id_set.end(),
                       std::back_inserter(*ids));
 }
 
+void Directory::OnCatastrophicError() {
+  ReadTransaction trans(FROM_HERE, this);
+  OnUnrecoverableError(&trans, FROM_HERE,
+                       "Catastrophic error detected, Sync DB is unrecoverable");
+}
+
 Directory::Kernel* Directory::kernel() {
   return kernel_;
 }
 
 const Directory::Kernel* Directory::kernel() const {
   return kernel_;
 }
 
 }  // namespace syncable
 }  // namespace syncer