buffer_pool_log.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 2022/02/01
//
 
#pragma once
 
#include "common/lang/string.h"
#include "common/types.h"
#include "common/sys/rc.h"
#include "storage/clog/log_replayer.h"
 
class DiskBufferPool;
class BufferPoolManager;
class LogHandler;
struct Page;
 
class BufferPoolOperation
{
public:
  enum class Type : int32_t
  {
    ALLOCATE,   
    DEALLOCATE  
  };
 
public:
  BufferPoolOperation(Type type) : type_(type) {}
  explicit BufferPoolOperation(int32_t type) : type_(static_cast<Type>(type)) {}
  ~BufferPoolOperation() = default;
 
  Type    type() const { return type_; }
  int32_t type_id() const { return static_cast<int32_t>(type_); }
 
  string to_string() const
  {
    string ret = std::to_string(type_id()) + ":";
    switch (type_) {
      case Type::ALLOCATE: return ret + "ALLOCATE";
      case Type::DEALLOCATE: return ret + "DEALLOCATE";
      default: return ret + "UNKNOWN";
    }
  }
 
private:
  Type type_;
};
 
struct BufferPoolLogEntry
{
  int32_t buffer_pool_id;  
  int32_t operation_type;  
  PageNum page_num;        
 
  string to_string() const;
};
 
class BufferPoolLogHandler final
{
public:
  BufferPoolLogHandler(DiskBufferPool &buffer_pool, LogHandler &log_handler);
  ~BufferPoolLogHandler() = default;
 
  RC allocate_page(PageNum page_num, LSN &lsn);
 
  RC deallocate_page(PageNum page_num, LSN &lsn);
 
  RC flush_page(Page &page);
 
private:
  RC append_log(BufferPoolOperation::Type type, PageNum page_num, LSN &lsn);
 
private:
  DiskBufferPool &buffer_pool_;
  LogHandler     &log_handler_;
};
 
class BufferPoolLogReplayer final : public LogReplayer
{
public:
  BufferPoolLogReplayer(BufferPoolManager &bp_manager);
  virtual ~BufferPoolLogReplayer() = default;
 
  RC replay(const LogEntry &entry) override;
 
private:
  BufferPoolManager &bp_manager_;
};