| // Copyright 2014 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 COMPONENTS_SYNC_MODEL_CHANGE_PROCESSOR_H_ |
| #define COMPONENTS_SYNC_MODEL_CHANGE_PROCESSOR_H_ |
| |
| #include <stdint.h> |
| |
| #include <memory> |
| |
| #include "base/macros.h" |
| #include "components/sync/model/data_type_error_handler.h" |
| #include "components/sync/syncable/base_transaction.h" |
| #include "components/sync/syncable/change_record.h" |
| #include "components/sync/syncable/user_share.h" |
| |
| namespace syncer { |
| |
| class ModelAssociator; |
| class UnrecoverableErrorHandler; |
| |
| // An interface used to apply changes from the sync model to the browser's |
| // native model. This does not currently distinguish between model data types. |
| class ChangeProcessor { |
| public: |
| explicit ChangeProcessor(std::unique_ptr<DataTypeErrorHandler> error_handler); |
| virtual ~ChangeProcessor(); |
| |
| // Call when the processor should accept changes from either provided model |
| // and apply them to the other. Both the native model and sync_api are |
| // expected to be initialized and loaded. You must have set a valid |
| // ModelAssociator and UnrecoverableErrorHandler before using this method, and |
| // the two models should be associated w.r.t the ModelAssociator provided. |
| void Start(UserShare* share_handle); |
| |
| // Changes have been applied to the backend model and are ready to be |
| // applied to the frontend model. |
| virtual void ApplyChangesFromSyncModel( |
| const BaseTransaction* trans, |
| int64_t model_version, |
| const ImmutableChangeRecordList& changes) = 0; |
| |
| // The changes found in ApplyChangesFromSyncModel may be too slow to be |
| // performed while holding a [Read/Write]Transaction lock or may interact |
| // with another thread, which might itself be waiting on the transaction lock, |
| // putting us at risk of deadlock. |
| // This function is called once the transactional lock is released and it is |
| // safe to perform inter-thread or slow I/O operations. Note that not all |
| // datatypes need this, so we provide an empty default version. |
| virtual void CommitChangesFromSyncModel(); |
| |
| protected: |
| // These methods are invoked by Start() and Stop() to do |
| // implementation-specific work. |
| virtual void StartImpl() = 0; |
| |
| DataTypeErrorHandler* error_handler() const; |
| virtual UserShare* share_handle() const; |
| |
| private: |
| std::unique_ptr<DataTypeErrorHandler> error_handler_; |
| |
| // The sync model we are processing changes from. |
| UserShare* share_handle_; |
| |
| DISALLOW_COPY_AND_ASSIGN(ChangeProcessor); |
| }; |
| |
| } // namespace syncer |
| |
| #endif // COMPONENTS_SYNC_MODEL_CHANGE_PROCESSOR_H_ |