pika_binlog_reader.h

// Copyright (c) 2015-present, Qihoo, Inc.  All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.

#ifndef PIKA_BINLOG_READER_H_
#define PIKA_BINLOG_READER_H_

#include <string>
#include <memory>

#include "slash/include/slash_status.h"
#include "slash/include/env.h"
#include "slash/include/slash_slice.h"

#include "include/pika_binlog.h"

using slash::Status;
using slash::Slice;

class PikaBinlogReader {
 public:
  PikaBinlogReader(uint32_t cur_filenum, uint64_t cur_offset);
  PikaBinlogReader();
  ~PikaBinlogReader();
  Status Get(std::string* scratch, uint32_t* filenum, uint64_t* offset);
  int Seek(std::shared_ptr<Binlog> logger, uint32_t filenum, uint64_t offset);
  bool ReadToTheEnd();
  void GetReaderStatus(uint32_t* cur_filenum, uint64_t* cur_offset);
 private:
  bool GetNext(uint64_t* size);
  unsigned int ReadPhysicalRecord(slash::Slice *redult, uint32_t* filenum, uint64_t* offset);
  // Returns scratch binflog and corresponding offset
  Status Consume(std::string* scratch, uint32_t* filenum, uint64_t* offset);

  pthread_rwlock_t rwlock_;
  uint32_t cur_filenum_;
  uint64_t cur_offset_;
  uint64_t last_record_offset_;

  std::shared_ptr<Binlog> logger_;
  slash::SequentialFile *queue_;

  char* const backing_store_;
  Slice buffer_;
};

#endif  // PIKA_BINLOG_READER_H_