MarisaDict.hpp

/*
 * Open Chinese Convert
 *
 * Copyright 2020 Carbo Kuo <byvoid@byvoid.com>
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 
#pragma once
 
#include <atomic>
#include <functional>
#include <mutex>
 
#include "Common.hpp"
#include "SerializableDict.hpp"
 
namespace marisa {
class Trie;
}
 
namespace opencc {
class OPENCC_EXPORT MarisaDict : public Dict, public SerializableDict {
public:
  virtual ~MarisaDict() override;
 
  virtual size_t KeyMaxLength() const override;
 
  virtual Optional<const DictEntry*> Match(const char* word,
                                           size_t len) const override;
 
  virtual Optional<const DictEntry*> MatchPrefix(const char* word,
                                                 size_t len) const override;
 
  virtual std::vector<const DictEntry*> MatchAllPrefixes(
      const char* word, size_t len) const override;
 
  virtual LexiconPtr GetLexicon() const override;
 
  virtual bool SupportsFastPrefixMatch() const override { return true; }
 
  virtual PrefixMatchView MatchPrefixValue(const char* word,
                                           size_t len) const override;

  bool EnumerateKeys(const std::function<void(const char*, size_t)>& cb) const;
 
  virtual void SerializeToFile(FILE* fp) const override;

  static MarisaDictPtr NewFromDict(const Dict& thatDict);
 
  static MarisaDictPtr NewFromFile(FILE* fp);
 
  static MarisaDictPtr NewFromBuffer(const char* data, size_t size);
 
  // Exposed for testing only.
  bool IsLexiconReconstructed() const {
    return lexiconReconstructed.load(std::memory_order_acquire);
  }
 
private:
  MarisaDict();
 
  void LoadFromMappedBuffer();
  void ReconstructLexicon() const;
 
  mutable size_t maxLength;
  mutable LexiconPtr lexicon;
  mutable std::mutex lexiconMutex;
  mutable std::atomic<bool> lexiconReconstructed;
  LexiconPtr valuesLexicon;
 
  class MarisaInternal;
  std::unique_ptr<MarisaInternal> internal;
};
} // namespace opencc