mariadb-columnstore-engine/primitives/blockcache/filebuffer.h

/* Copyright (C) 2014 InfiniDB, Inc.

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License
   as published by the Free Software Foundation; version 2 of
   the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
   MA 02110-1301, USA. */

/***************************************************************************
 *
 *   $Id: filebuffer.h 2035 2013-01-21 14:12:19Z rdempsey $
 *
 *   jrodriguez@calpont.com   *
 *                                                                         *
 ***************************************************************************/

#pragma once

#include <stdio.h>
#include <stdlib.h>
#include <string>
#include <stdexcept>
#include <stdint.h>
#include <time.h>
#include "brmtypes.h"
#include <list>
#include <vector>
#include "blocksize.h"

/**
        @author Jason Rodriguez <jrodriguez@calpont.com>
*/

/**
 * @brief represents a disk blockrequest
 **/
namespace dbbc
{
typedef struct FBData
{
  BRM::LBID_t lbid;
  BRM::VER_t ver;
  uint8_t hits;
} FBData_t;

//@bug 669 Change to list for least recently used cache
typedef std::list<FBData_t> filebuffer_list_t;
typedef std::list<FBData_t>::iterator filebuffer_list_iter_t;

class FileBuffer
{
 public:
  FileBuffer();
  /**
   * @brief copy ctor
   **/
  FileBuffer(const FileBuffer& fb);

  /**
   * @brief the disk block from lbid@ver, and a data block len bytes long
   **/
  FileBuffer(const BRM::LBID_t lbid, const BRM::VER_t ver, const uint8_t* data, const uint32_t len);

  /**
   * @brief disk block lbid@ver and empty data
   **/
  FileBuffer(const BRM::LBID_t lbid, const BRM::VER_t ver);

  /**
   * @brief class dtor
   **/
  ~FileBuffer();

  /**
   * @brief set the data value of this block to d have len bytestream
   **/
  void setData(const uint8_t* d, const int len);
  void setData(const uint8_t* d);  // assumes len = 8192

  /**
   * @brief retrieve the data in byte* format from this data block
   **/
  inline const uint8_t* getData() const
  {
    return fByteData;
  }
  inline uint8_t* getData()
  {
    return fByteData;
  }

  inline uint32_t datLen() const
  {
    return fDataLen;
  }

  /**
   * @brief assignment operator
   **/
  FileBuffer& operator=(const FileBuffer& rhs);

  /**
   * @brief equality operator is based on lbid@ver
   **/
  inline bool operator==(const FileBuffer& rhs) const
  {
    return (fLbid == rhs.fLbid && fVerid == rhs.fVerid);
  }

  /**
   * @brief inequality operator
   **/
  inline bool operator!=(const FileBuffer& rhs) const
  {
    return (!(fLbid == rhs.fLbid && fVerid == rhs.fVerid));
  }

  FileBuffer* thisPtr()
  {
    return this;
  }
  /**
   * @brief return the lbid value of disk bloc
   **/
  inline BRM::LBID_t Lbid() const
  {
    return fLbid;
  }
  inline void Lbid(const BRM::LBID_t l)
  {
    fLbid = l;
  }

  /**
   * @brief return the version of this disk block. ignored for range retrievals
   **/
  inline BRM::VER_t Verid() const
  {
    return fVerid;
  }
  inline void Verid(BRM::VER_t v)
  {
    fVerid = v;
  }

  /**
   * @brief return the number of bytes in this disk blockrequest
   **/

  inline void listLoc(const filebuffer_list_iter_t& loc)
  {
    fListLoc = loc;
  }

  inline const filebuffer_list_iter_t& listLoc() const
  {
    return fListLoc;
  }

 private:
  uint8_t fByteData[BLOCK_SIZE];
  uint32_t fDataLen;
  BRM::LBID_t fLbid;
  BRM::VER_t fVerid;
  filebuffer_list_iter_t fListLoc;
};

typedef std::vector<FileBuffer> FileBufferPool_t;

}  // namespace dbbc