| // Copyright 2017 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_ZUCCHINI_ENSEMBLE_MATCHER_H_ |
| #define COMPONENTS_ZUCCHINI_ENSEMBLE_MATCHER_H_ |
| |
| #include <stddef.h> |
| |
| #include <vector> |
| |
| #include "components/zucchini/buffer_view.h" |
| #include "components/zucchini/element_detection.h" |
| #include "components/zucchini/image_utils.h" |
| |
| namespace zucchini { |
| |
| // A base class for ensemble matching strategies, which identify Elements in a |
| // "new" and "old" archives, and match each "new" Element to an "old" Element. |
| // Matched pairs can then be passed to Disassembler for architecture-specific |
| // patching. Notes: |
| // - A matched Element pair must have the same ExecutableType. |
| // - Special case: Exact matches are ignored, since they can be patched directly |
| // without architecture-specific patching. |
| // - Multiple "new" Elements may match a common "old" Element. |
| // - A "new" Element may have no match. This can happen when no viable match |
| // exists, or when an exact match is skipped. |
| class EnsembleMatcher { |
| public: |
| EnsembleMatcher(); |
| EnsembleMatcher(const EnsembleMatcher&) = delete; |
| const EnsembleMatcher& operator=(const EnsembleMatcher&) = delete; |
| virtual ~EnsembleMatcher(); |
| |
| // Interface to main matching feature. Returns whether match was successful. |
| // This should be called at most once per instace. |
| virtual bool RunMatch(ConstBufferView old_image, |
| ConstBufferView new_image) = 0; |
| |
| // Accessors to RunMatch() results. |
| const std::vector<ElementMatch>& matches() const { return matches_; } |
| |
| size_t num_identical() const { return num_identical_; } |
| |
| protected: |
| // Post-processes |matches_| to remove potentially unfavorable entries. |
| void Trim(); |
| |
| // Storage of matched elements: A list of matched pairs, where the list of |
| // "new" elements have increasing offsets and don't overlap. May be empty. |
| std::vector<ElementMatch> matches_; |
| |
| // Number of identical matches found in match candidates. These should be |
| // excluded from |matches_|. |
| size_t num_identical_ = 0; |
| }; |
| |
| } // namespace zucchini |
| |
| #endif // COMPONENTS_ZUCCHINI_ENSEMBLE_MATCHER_H_ |