Initial commit of sync engine code to browser/sync....

chrome/browser/sync/engine/update_applicator.h

+// Copyright (c) 2009 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.
+//
+// An UpdateApplicator is used to iterate over a number of unapplied
+// updates, applying them to the client using the given syncer session.
+//
+// UpdateApplicator might resemble an iterator, but it actually keeps retrying
+// failed updates until no remaining updates can be successfully applied.
+
+#ifndef CHROME_BROWSER_SYNC_ENGINE_UPDATE_APPLICATOR_H_
+#define CHROME_BROWSER_SYNC_ENGINE_UPDATE_APPLICATOR_H_
+
+#include <vector>
+#include <set>
+
+#include "base/basictypes.h"
+#include "base/port.h"
+
+namespace syncable {
+class Id;
+class WriteTransaction;
+}  // namespace syncable
+
+namespace browser_sync {
+
+class SyncerSession;
+
+class UpdateApplicator {
+ public:
+  typedef std::vector<int64>::iterator vi64iter;
+
+  UpdateApplicator(SyncerSession* session, const vi64iter& begin,
+                   const vi64iter& end);
+  // returns true if there's more we can do.
+  bool AttemptOneApplication(syncable::WriteTransaction* trans);
+  // return true if we've applied all updates.
+  bool AllUpdatesApplied() const;
+
+  // This class does not automatically save its progress into the
+  // SyncerSession -- to get that to happen, call this method after
+  // update application is finished (i.e., when AttemptOneAllocation
+  // stops returning true).
+  void SaveProgressIntoSessionState();
+
+ private:
+  SyncerSession* const session_;
+  vi64iter const begin_;
+  vi64iter end_;
+  vi64iter pointer_;
+  bool progress_;
+
+  // Track the result of the various items.
+  std::vector<syncable::Id> conflicting_ids_;
+  std::vector<syncable::Id> blocked_ids_;
+  std::vector<syncable::Id> successful_ids_;
+};
+
+}  // namespace browser_sync
+
+#endif  // CHROME_BROWSER_SYNC_ENGINE_UPDATE_APPLICATOR_H_