| // Copyright 2016 The Fuchsia 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 PERIDOT_BIN_LEDGER_APP_MERGING_MERGE_STRATEGY_H_ |
| #define PERIDOT_BIN_LEDGER_APP_MERGING_MERGE_STRATEGY_H_ |
| |
| #include <memory> |
| |
| #include <lib/fit/function.h> |
| |
| #include "peridot/bin/ledger/app/merging/merge_resolver.h" |
| #include "peridot/bin/ledger/fidl/include/types.h" |
| #include "peridot/bin/ledger/storage/public/commit.h" |
| #include "peridot/bin/ledger/storage/public/page_storage.h" |
| |
| namespace ledger { |
| class PageManager; |
| |
| // Interface for a merge algorithm. |
| class MergeStrategy { |
| public: |
| MergeStrategy() {} |
| virtual ~MergeStrategy() {} |
| |
| // Sets a callback that will be called if this strategy is not to be used |
| // anymore, for instance when the underlying merge mechanism is no longer |
| // available. This callback should not delete the strategy if there are merges |
| // in progress. |
| virtual void SetOnError(fit::function<void()> on_error) = 0; |
| |
| // Merge the given commits. head_1.timesteamp must be less or equals to |
| // head_2.timestamp. MergeStrategy should not be deleted while merges are in |
| // progress. |
| virtual void Merge(storage::PageStorage* storage, PageManager* page_manager, |
| std::unique_ptr<const storage::Commit> head_1, |
| std::unique_ptr<const storage::Commit> head_2, |
| std::unique_ptr<const storage::Commit> ancestor, |
| fit::function<void(Status)> callback) = 0; |
| |
| // Cancel an in-progress merge. This must be called after |Merge| has been |
| // called, and before the |on_done| callback. |
| virtual void Cancel() = 0; |
| |
| private: |
| FXL_DISALLOW_COPY_AND_ASSIGN(MergeStrategy); |
| }; |
| |
| } // namespace ledger |
| |
| #endif // PERIDOT_BIN_LEDGER_APP_MERGING_MERGE_STRATEGY_H_ |