Revert "Revert 142517 - [Sync] Refactor sync configuration logic."

sync/internal_api/sync_manager.cc

 // Copyright (c) 2012 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/internal_api/public/sync_manager.h"
 
 #include <string>
 
 #include "base/base64.h"
 #include "base/bind.h"
@@ skipping 179 matching lines @@
             UnrecoverableErrorHandler* unrecoverable_error_handler,
             ReportUnrecoverableErrorFunction
                 report_unrecoverable_error_function);
 
   // Sign into sync with given credentials.
   // We do not verify the tokens given. After this call, the tokens are set
   // and the sync DB is open. True if successful, false if something
   // went wrong.
   bool SignIn(const SyncCredentials& credentials);
 
+  // Purge from the directory those types with non-empty progress markers
+  // but without initial synced ended set.
+  // Returns false if an error occurred, true otherwise.
+  bool PurgePartiallySyncedTypes();
+
   // Update tokens that we're using in Sync. Email must stay the same.
   void UpdateCredentials(const SyncCredentials& credentials);
 
   // Called when the user disables or enables a sync type.
   void UpdateEnabledTypes(const ModelTypeSet& enabled_types);
 
   // Tell the sync engine to start the syncing process.
   void StartSyncingNormally(
       const syncer::ModelSafeRoutingInfo& routing_info);
 
@@ skipping 140 matching lines @@
                                 syncer::ModelType type,
                                 ChangeReorderBuffer* buffer,
                                 Cryptographer* cryptographer,
                                 const syncable::EntryKernel& original,
                                 bool existed_before,
                                 bool exists_now);
 
   // Called only by our NetworkChangeNotifier.
   virtual void OnIPAddressChanged() OVERRIDE;
 
+  ModelTypeSet GetTypesWithEmptyProgressMarkerToken(ModelTypeSet types) {
+    DCHECK(initialized_);
+    syncer::ModelTypeSet result;
+    for (syncer::ModelTypeSet::Iterator i = types.First();
+         i.Good(); i.Inc()) {
+      sync_pb::DataTypeProgressMarker marker;
+      directory()->GetDownloadProgress(i.Get(), &marker);
+
+      if (marker.token().empty())
+        result.Put(i.Get());
+
+    }
+    return result;
+  }
+
   syncer::ModelTypeSet InitialSyncEndedTypes() {
     DCHECK(initialized_);
     return directory()->initial_sync_ended_types();
   }
 
   // SyncEngineEventListener implementation.
   virtual void OnSyncEngineEvent(const SyncEngineEvent& event) OVERRIDE;
 
   // ServerConnectionEventListener implementation.
   virtual void OnServerConnectionEvent(
@@ skipping 374 matching lines @@
   DCHECK(thread_checker_.CalledOnValidThread());
   ReadTransaction trans(FROM_HERE, GetUserShare());
   trans.GetWrappedTrans()->OnUnrecoverableError(
       FROM_HERE, "Simulating unrecoverable error for testing purposes.");
 }
 
 syncer::ModelTypeSet SyncManager::InitialSyncEndedTypes() {
   return data_->InitialSyncEndedTypes();
 }
 
+syncer::ModelTypeSet SyncManager::GetTypesWithEmptyProgressMarkerToken(
+    syncer::ModelTypeSet types) {
+  return data_->GetTypesWithEmptyProgressMarkerToken(types);
+}
+
+bool SyncManager::PurgePartiallySyncedTypes() {
+  return data_->PurgePartiallySyncedTypes();
+}
+
 void SyncManager::StartSyncingNormally(
     const syncer::ModelSafeRoutingInfo& routing_info) {
   DCHECK(thread_checker_.CalledOnValidThread());
   data_->StartSyncingNormally(routing_info);
 }
 
 void SyncManager::SetEncryptionPassphrase(const std::string& passphrase,
                                           bool is_explicit) {
   DCHECK(thread_checker_.CalledOnValidThread());
   data_->SetEncryptionPassphrase(passphrase, is_explicit);
@@ skipping 153 matching lines @@
         workers,
         extensions_activity_monitor,
         &throttled_data_type_tracker_,
         listeners,
         &debug_info_event_listener_,
         &traffic_recorder_));
     session_context()->set_account_name(credentials.email);
     scheduler_.reset(new SyncScheduler(name_, session_context(), new Syncer()));
   }
 
-  bool signed_in = SignIn(credentials);
+  bool success = SignIn(credentials);
 
-  if (signed_in) {
+  if (success) {
     if (scheduler()) {
       scheduler()->Start(syncer::SyncScheduler::CONFIGURATION_MODE);
     }
 
     initialized_ = true;
 
+    // Unapplied datatypes (those that do not have initial sync ended set) get
+    // re-downloaded during any configuration. But, it's possible for a datatype
+    // to have a progress marker but not have initial sync ended yet, making
+    // it a candidate for migration. This is a problem, as the DataTypeManager
+    // does not support a migration while it's already in the middle of a
+    // configuration. As a result, any partially synced datatype can stall the
+    // DTM, waiting for the configuration to complete, which it never will due
+    // to the migration error. In addition, a partially synced nigori will
+    // trigger the migration logic before the backend is initialized, resulting
+    // in crashes. We therefore detect and purge any partially synced types as
+    // part of initialization.
+    if (!PurgePartiallySyncedTypes())
+      success = false;
+
     // Cryptographer should only be accessed while holding a
     // transaction.  Grabbing the user share for the transaction
     // checks the initialization state, so this must come after
     // |initialized_| is set to true.
     ReadTransaction trans(FROM_HERE, GetUserShare());
     trans.GetCryptographer()->Bootstrap(restored_key_for_bootstrapping);
     trans.GetCryptographer()->AddObserver(this);
   }
 
   // Notify that initialization is complete. Note: This should be the last to
   // execute if |signed_in| is false. Reason being in that case we would
   // post a task to shutdown sync. But if this function posts any other tasks
   // on the UI thread and if shutdown wins then that tasks would execute on
   // a freed pointer. This is because UI thread is not shut down.
   FOR_EACH_OBSERVER(SyncManager::Observer, observers_,
                     OnInitializationComplete(
                         MakeWeakHandle(weak_ptr_factory_.GetWeakPtr()),
-                        signed_in));
+                        success));
 
-  if (!signed_in && testing_mode_ == NON_TEST)
+  if (!success && testing_mode_ == NON_TEST)
     return false;
 
   sync_notifier_->AddObserver(this);
 
-  return signed_in;
+  return success;
 }
 
 void SyncManager::SyncInternal::UpdateCryptographerAndNigori(
     const std::string& chrome_version,
     const base::Closure& done_callback) {
   DCHECK(initialized_);
   syncer::GetSessionName(
       blocking_task_runner_,
       base::Bind(
           &SyncManager::SyncInternal::UpdateCryptographerAndNigoriCallback,
@@ skipping 184 matching lines @@
   allstatus_.SetUniqueId(unique_id);
   sync_notifier_->SetUniqueId(unique_id);
   // TODO(tim): Remove once invalidation state has been migrated to new
   // InvalidationStateTracker store. Bug 124140.
   sync_notifier_->SetStateDeprecated(state);
 
   UpdateCredentials(credentials);
   return true;
 }
 
+bool SyncManager::SyncInternal::PurgePartiallySyncedTypes() {
+  syncer::ModelTypeSet partially_synced_types =
+      syncer::ModelTypeSet::All();
+  partially_synced_types.RemoveAll(InitialSyncEndedTypes());
+  partially_synced_types.RemoveAll(GetTypesWithEmptyProgressMarkerToken(
+      syncer::ModelTypeSet::All()));
+
+  UMA_HISTOGRAM_COUNTS("Sync.PartiallySyncedTypes",
+                       partially_synced_types.Size());
+  if (partially_synced_types.Empty())
+    return true;
+  return directory()->PurgeEntriesWithTypeIn(partially_synced_types);
+}
+
 void SyncManager::SyncInternal::UpdateCredentials(
     const SyncCredentials& credentials) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK_EQ(credentials.email, share_.name);
   DCHECK(!credentials.email.empty());
   DCHECK(!credentials.sync_token.empty());
 
   observing_ip_address_changes_ = true;
   if (connection_manager()->set_auth_token(credentials.sync_token)) {
     sync_notifier_->UpdateCredentials(
@@ skipping 1290 matching lines @@
 bool InitialSyncEndedForTypes(syncer::ModelTypeSet types,
                               syncer::UserShare* share) {
   for (syncer::ModelTypeSet::Iterator i = types.First();
        i.Good(); i.Inc()) {
     if (!share->directory->initial_sync_ended_for_type(i.Get()))
       return false;
   }
   return true;
 }
 
-syncer::ModelTypeSet GetTypesWithEmptyProgressMarkerToken(
-    syncer::ModelTypeSet types,
-    syncer::UserShare* share) {
-  syncer::ModelTypeSet result;
-  for (syncer::ModelTypeSet::Iterator i = types.First();
-       i.Good(); i.Inc()) {
-    sync_pb::DataTypeProgressMarker marker;
-    share->directory->GetDownloadProgress(i.Get(), &marker);
-
-    if (marker.token().empty())
-      result.Put(i.Get());
-
-  }
-  return result;
-}
-
 }  // namespace syncer