ring_buffer.h

/* Copyright (c) 2021 OceanBase and/or its affiliates. All rights reserved.
miniob is licensed under Mulan PSL v2.
You can use this software according to the terms and conditions of the Mulan PSL v2.
You may obtain a copy of Mulan PSL v2 at:
         http://license.coscl.org.cn/MulanPSL2
THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
See the Mulan PSL v2 for more details. */
 
//
// Created by Wangyunlai on 2023/06/16.
//
 
#pragma once
 
#include <vector>
 
#include "common/rc.h"
 
class RingBuffer
{
public:
  RingBuffer();
 
  explicit RingBuffer(int32_t size);
 
  virtual ~RingBuffer();
 
  RC read(char *buf, int32_t size, int32_t &read_size);
 
  RC buffer(const char *&buf, int32_t &read_size);
 
  RC forward(int32_t size);
 
  RC write(const char *buf, int32_t size, int32_t &write_size);
 
  int32_t capacity() const { return static_cast<int32_t>(buffer_.size()); }
 
  int32_t remain() const { return capacity() - size(); }
 
  int32_t size() const { return data_size_; }
 
private:
  int32_t read_pos() const { return (write_pos_ - this->size() + capacity()) % capacity(); }
  
private:
  std::vector<char> buffer_;      
  int32_t data_size_ = 0;         
  int32_t write_pos_ = 0;         
};