Index: courgette/label_manager.h |
diff --git a/courgette/label_manager.h b/courgette/label_manager.h |
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+// Copyright 2015 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 COURGETTE_LABEL_MANAGER_H_ |
+#define COURGETTE_LABEL_MANAGER_H_ |
+ |
+#include <vector> |
+ |
+#include "base/macros.h" |
+#include "courgette/image_utils.h" |
+ |
+namespace courgette { |
+ |
+// A container to store and manage Label instances. A key consideration is peak |
+// memory usage reduction. To this end we preallocate Label instances in bulk, |
+// and carefully control transient memory usage when initializing Labels. |
+class LabelManager { |
+ public: |
+ // An adaptor to sequentially traverse multiple RVAs. This is useful for RVA |
+ // translation without extra storage. For example, we might have a stored list |
+ // of RVA locations, but we want to traverse the matching RVA targets. |
+ class RvaVisitor { |
+ public: |
+ virtual ~RvaVisitor(); |
+ |
+ // Returns the number of remaining RVAs to visit. |
+ virtual size_t Remaining() const = 0; |
+ |
+ // Returns the current RVA. |
+ virtual RVA Get() const = 0; |
+ |
+ // Advances to the next RVA. |
+ virtual void Next() = 0; |
+ }; |
+ |
+ LabelManager(); |
+ virtual ~LabelManager(); |
+ |
+ // Initializes |labels_| using RVAs from |rva_visitor|. Each distinct RVA from |
+ // |rva_visitor| yields a Label with |rva_| assigned as the RVA, and |count_| |
+ // assigned as the repeat. |
+ void Read(RvaVisitor* rva_visitor); |
+ |
+ // Removes |labels_| elements whose |count_| is less than |count_threshold|. |
+ void RemoveUnderusedLabels(int32 count_threshold); |
+ |
+ // Efficiently searches for a Label that targets |rva|. Returns the pointer to |
+ // the stored Label instance if found, or null otherwise. |
+ Label* Find(RVA rva); |
+ |
+ // TODO(huangs): Move AssignRemainingIndexes() here. |
+ |
+ protected: |
+ // The main list of Label instances, sorted by the |rva_| member. |
+ std::vector<Label> labels_; |
+ |
+ private: |
+ DISALLOW_COPY_AND_ASSIGN(LabelManager); |
+}; |
+ |
+} // namespace courgette |
+ |
+#endif // COURGETTE_LABEL_MANAGER_H_ |