sync: Implement per-type commit interface

sync/sessions/ordered_commit_set.h

-// Copyright 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.
-
-#ifndef SYNC_SESSIONS_ORDERED_COMMIT_SET_H_
-#define SYNC_SESSIONS_ORDERED_COMMIT_SET_H_
-
-#include <map>
-#include <set>
-#include <vector>
-
-#include "sync/base/sync_export.h"
-#include "sync/internal_api/public/base/model_type.h"
-#include "sync/internal_api/public/engine/model_safe_worker.h"
-
-namespace syncer {
-namespace sessions {
-
-// TODO(ncarter): This code is more generic than just Commit and can
-// be reused elsewhere (e.g. ChangeReorderBuffer do similar things).  Merge
-// all these implementations.
-class SYNC_EXPORT_PRIVATE OrderedCommitSet {
- public:
-  // TODO(chron): Reserve space according to batch size?
-  OrderedCommitSet();
-  ~OrderedCommitSet();
-
-  bool HaveCommitItem(const int64 metahandle) const {
-    return inserted_metahandles_.count(metahandle) > 0;
-  }
-
-  void AddCommitItem(const int64 metahandle, ModelType type);
-  void AddCommitItems(const std::vector<int64> metahandles, ModelType type);
-
-  const std::vector<int64>& GetAllCommitHandles() const {
-    return metahandle_order_;
-  }
-
-  // Return the handle at index |position| in this OrderedCommitSet.  Note that
-  // the index uniquely identifies the same logical item in each of:
-  // 1) this OrderedCommitSet
-  // 2) the CommitRequest sent to the server
-  // 3) the list of EntryResponse objects in the CommitResponse.
-  // These together allow re-association of the pre-commit Id with the
-  // actual committed entry.
-  int64 GetCommitHandleAt(const size_t position) const {
-    return metahandle_order_[position];
-  }
-
-  // Same as above, but for ModelType of the item.
-  ModelType GetModelTypeAt(const size_t position) const {
-    return types_[position];
-  }
-
-  size_t Size() const {
-    return metahandle_order_.size();
-  }
-
-  bool Empty() const {
-    return Size() == 0;
-  }
-
-  // Returns all the types that are included in this list.
-  ModelTypeSet Types() const {
-    return types_in_list_;
-  }
-
-  // Returns true iff any of the commit ids added to this set have model type
-  // BOOKMARKS.
-  bool HasBookmarkCommitId() const;
-
-  void Append(const OrderedCommitSet& other);
-  void AppendReverse(const OrderedCommitSet& other);
-  void Truncate(size_t max_size);
-
-  // Removes all entries from this set.
-  void Clear();
-
-  void operator=(const OrderedCommitSet& other);
- private:
-  // Helper container for return value of GetCommitItemAt.
-  struct CommitItem {
-    int64 meta;
-    ModelType group;
-  };
-
-  CommitItem GetCommitItemAt(const size_t position) const;
-
-  // These lists are different views of the same items; e.g they are
-  // isomorphic.
-  std::set<int64> inserted_metahandles_;
-  std::vector<int64> metahandle_order_;
-
-  // We need this because of operations like AppendReverse that take ids from
-  // one OrderedCommitSet and insert into another -- we need to know the
-  // group for each ID so that the insertion can update the appropriate
-  // projection.
-  std::vector<ModelType> types_;
-
-  // The set of types which are included in this particular list.
-  ModelTypeSet types_in_list_;
-};
-
-}  // namespace sessions
-}  // namespace syncer
-
-#endif  // SYNC_SESSIONS_ORDERED_COMMIT_SET_H_
-