[Sync] Refactor non-frontend DTC to handle new API properly.

chrome/browser/sync/glue/shared_change_processor.cc

Index: chrome/browser/sync/glue/shared_change_processor.cc
diff --git a/chrome/browser/sync/glue/shared_change_processor.cc b/chrome/browser/sync/glue/shared_change_processor.cc
new file mode 100644
index 0000000000000000000000000000000000000000..129cd96697993e071b03ed9faacfa5d39a617bee
--- /dev/null
+++ b/chrome/browser/sync/glue/shared_change_processor.cc
@@ -0,0 +1,104 @@
+// Copyright (c) 2011 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 "chrome/browser/sync/glue/shared_change_processor.h"
+
+#include "base/location.h"
+#include "chrome/browser/sync/api/syncable_service.h"
+#include "chrome/browser/sync/api/sync_change.h"
+#include "chrome/browser/sync/api/sync_error.h"
+#include "content/browser/browser_thread.h"
+
+using base::AutoLock;
+
+namespace browser_sync {
+
+SharedChangeProcessor::SharedChangeProcessor(
+    UnrecoverableErrorHandler* error_handler)
+    : GenericChangeProcessor(error_handler),
+      disconnected_(false) {
+  // We're always created on the UI thread.
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DetachFromThread();
+}
+
+SharedChangeProcessor::~SharedChangeProcessor() {
+  // We should always be deleted on the UI thread.
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DetachFromThread();
+}
+
+// Connect to the syncer and SyncableService specified.
+void SharedChangeProcessor::Connect(SyncableService* local_service,
+                                    sync_api::UserShare* user_share) {
+  DCHECK(!BrowserThread::CurrentlyOn(BrowserThread::UI));
+  DCHECK(CalledOnValidThread());
+  AutoLock lock(monitor_lock_);
+  if (disconnected_)
+    return;
+  DCHECK(local_service);
+  set_local_service(local_service);
+  set_share_handle(user_share);
+}
+
+void SharedChangeProcessor::Disconnect() {
+  // May be called from any thread.
+  VLOG(1) << "Disconnecting change processor.";
+  AutoLock lock(monitor_lock_);
+  disconnected_ = true;
+}
+
+SyncError SharedChangeProcessor::GetSyncDataForType(
+    syncable::ModelType type,
+    SyncDataList* current_sync_data) {
+  DCHECK(CalledOnValidThread());
+  AutoLock lock(monitor_lock_);
+  if (disconnected_) {
+    SyncError error(FROM_HERE, "Change processor disconnected.", type);
+    return error;
+  }
+  return GenericChangeProcessor::GetSyncDataForType(type, current_sync_data);
+}
+
+SyncError SharedChangeProcessor::ProcessSyncChanges(
+    const tracked_objects::Location& from_here,
+    const SyncChangeList& list_of_changes) {
+  DCHECK(CalledOnValidThread());
+  AutoLock lock(monitor_lock_);
+  if (disconnected_) {
+    // The DTC that disconnects us must ensure it posts a StopSyncing task.
+    // If we reach this, it means it just hasn't executed yet.
+    syncable::ModelType type;
+    if (list_of_changes.size() > 0) {
+      type = list_of_changes[0].sync_data().GetDataType();
+    }
+    SyncError error(FROM_HERE, "Change processor disconnected.", type);
+    return error;
+  }
+  return GenericChangeProcessor::ProcessSyncChanges(from_here, list_of_changes);
+}
+
+bool SharedChangeProcessor::SyncModelHasUserCreatedNodes(
+    syncable::ModelType type,
+    bool* has_nodes) {
+  DCHECK(CalledOnValidThread());
+  AutoLock lock(monitor_lock_);
+  if (disconnected_) {
+    LOG(ERROR) << "Change processor disconnected.";
+    return false;
+  }
+  return GenericChangeProcessor::SyncModelHasUserCreatedNodes(type, has_nodes);
+}
+
+bool SharedChangeProcessor::CryptoReadyIfNecessary(syncable::ModelType type) {
+  DCHECK(CalledOnValidThread());
+  AutoLock lock(monitor_lock_);
+  if (disconnected_) {
+    LOG(ERROR) << "Change processor disconnected.";
+    return true;  // Otherwise we get into infinite spin waiting.
+  }
+  return GenericChangeProcessor::CryptoReadyIfNecessary(type);
+}
+
+}  // namespace browser_sync