sync: Add interfaces for per-type sync

sync/engine/sync_directory_commit_contribution.h

-// 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.
-
-#ifndef SYNC_ENGINE_SYNC_DIRECTORY_COMMIT_CONTRIBUTION_H_
-#define SYNC_ENGINE_SYNC_DIRECTORY_COMMIT_CONTRIBUTION_H_
-
-#include <vector>
-
-#include "base/gtest_prod_util.h"
-#include "sync/base/sync_export.h"
-#include "sync/internal_api/public/base/model_type.h"
-#include "sync/internal_api/public/util/syncer_error.h"
-#include "sync/protocol/sync.pb.h"
-#include "sync/sessions/status_controller.h"
-
-namespace syncer {
-
-namespace sessions {
-class StatusController;
-}  // namespace sessions
-
-namespace syncable {
-class Directory;
-}  // namespace syncable
-
-// This class represents a set of items belonging to a particular data type that
-// have been selected from the syncable Directory and prepared for commit.
-//
-// This class handles the bookkeeping related to the commit of these items,
-// including processing the commit response message and setting and unsetting
-// the SYNCING bits.
-class SYNC_EXPORT_PRIVATE SyncDirectoryCommitContribution {
- public:
-  // This destructor will DCHECK if UnsetSyncingBits() has not been called yet.
-  ~SyncDirectoryCommitContribution();
-
-  // Build a CommitContribution from the IS_UNSYNCED items in |dir| with the
-  // given |type|.  The contribution will include at most |max_items| entries.
-  //
-  // This function may return NULL if this type has no items ready for and
-  // requiring commit.  This function may make model neutral changes to the
-  // directory.
-  static SyncDirectoryCommitContribution* Build(
-      syncable::Directory* dir,
-      ModelType type,
-      size_t max_items);
-
-  // Serialize this contribution's entries to the given commit request |msg|.
-  //
-  // This function is not const.  It will update some state in this contribution
-  // that will be used when processing the associated commit response.  This
-  // function should not be called more than once.
-  void AddToCommitMessage(sync_pb::ClientToServerMessage* msg);
-
-  // Updates this contribution's contents in accordance with the provided
-  // |response|.
-  //
-  // This function may make model-neutral changes to the directory.  It is not
-  // valid to call this function unless AddToCommitMessage() was called earlier.
-  // This function should not be called more than once.
-  SyncerError ProcessCommitResponse(
-      const sync_pb::ClientToServerResponse& response,
-      sessions::StatusController* status);
-
-  // Cleans up any temproary state associated with the commit.  Must be called
-  // before destruction.
-  void CleanUp();
-
-  // Returns the number of entries included in this contribution.
-  size_t GetNumEntries() const;
-
- private:
-  class SyncDirectoryCommitContributionTest;
-  FRIEND_TEST_ALL_PREFIXES(SyncDirectoryCommitContributionTest, GatherByTypes);
-  FRIEND_TEST_ALL_PREFIXES(SyncDirectoryCommitContributionTest,
-                           GatherAndTruncate);
-
-  SyncDirectoryCommitContribution(
-      const std::vector<int64>& metahandles,
-      const google::protobuf::RepeatedPtrField<sync_pb::SyncEntity>& entities,
-      syncable::Directory* directory);
-
-  void UnsetSyncingBits();
-
-  syncable::Directory* dir_;
-  const std::vector<int64> metahandles_;
-  const google::protobuf::RepeatedPtrField<sync_pb::SyncEntity> entities_;
-  size_t entries_start_index_;
-
-  // This flag is tracks whether or not the directory entries associated with
-  // this commit still have their SYNCING bits set.  These bits will be set when
-  // the CommitContribution is created with Build() and unset when CleanUp() is
-  // called.  This flag must be unset by the time our destructor is called.
-  bool syncing_bits_set_;
-
-  DISALLOW_COPY_AND_ASSIGN(SyncDirectoryCommitContribution);
-};
-
-}  // namespace syncer
-
-#endif  // SYNC_ENGINE_SYNC_DIRECTORY_COMMIT_CONTRIBUTION_H_