bufmgr.h

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/*
 * SwatDB
 *
 * @authors: See Contributors.doc for code contributors
 *
 * Copyright (c) 2020,2025 Swarthmore College Computer Science Department
 * Swarthmore PA, Professors Tia Newhall, Ameet Soni
 */
 
// @@@@ SWATDB_ASSIGNMENT: ADDTODODATE
 
#ifndef _SWATDB_BUFMGER_H_
#define  _SWATDB_BUFMGER_H_
 
#include <utility>
#include <unordered_map>
#include <mutex>
#include <list>
#include <queue>
 
#include "swatdb_types.h"
#include "page.h"           // need for alignment of Page object
#include "bm_buffermap.h"   // BufferMap class
#include "bm_frame.h"       // Frame class
                            
 
// @@@@ SWATDB_ASSIGNMENT: CUT_START
// if this is defined: disables some policies for lab assignmnet solution
// (right now if defined it includes Random and Clock only)
// Either uncomment this or -DBUFMGR_LAB_SOL_OMIT=1 in Makefile to define this 
//#define BUFMGR_LAB_SOL_OMIT  (1)
// @@@@ SWATDB_ASSIGNMENT: CUT_END
 
// can't just include bm_replacement.h or circular dependenices with .h file
// (one shortcomming of #pragma once)
class ReplacementPolicy;
class DiskManager;
 
 
 
// @@@@ SWATDB_ASSIGNMENT: NOTEMSG Do not modify this struct
struct BufferState {
 
  std::uint32_t total;
 
  std::uint32_t valid;
 
  std::uint32_t pinned;
 
  std::uint32_t unpinned;
 
  std::uint32_t dirty;
 
  struct ReplacementStats {
 
    RepType rep_type;
    std::uint64_t rep_calls;
   
    std::uint64_t new_page_calls;
 
    double avg_frames_checked;
 
    std::uint32_t ref_bit;
 
    std::uint32_t clock_hand;
  } replace_stats;
 
};
 
 
// @@@@ SWATDB_ASSIGNMENT: NOTEMSG Do not modify this definition, you may add private helper methods only
class BufferManager {
 
  public:
 
    BufferManager(DiskManager *disk_mgr, RepType rep_type);
 
    ~BufferManager();
 
    std::pair<Page*,PageId> allocatePage(FileId file_id);
 
// @@@@ SWATDB_ASSIGNMENT: CUT_START
    std::pair<Page*, PageId> allocateAnonymousPage();
// @@@@ SWATDB_ASSIGNMENT: CUT_END
 
    void deallocatePage(PageId page_id);
 
// @@@@ SWATDB_ASSIGNMENT: CUT_START
    void deallocateAnonymousPage(PageId page_id);
// @@@@ SWATDB_ASSIGNMENT: CUT_END
 
    Page* getPage(PageId page_id);
 
    void releasePage(PageId page_id, bool dirty);
 
    void setDirty(PageId page_id);
 
    void flushPage(PageId page_id);
 
    void createFile(FileId file_id);
 
    void removeFile(FileId file_id);
 
// @@@@ SWATDB_ASSIGNMENT: CUT_START
    void clearBuffer();
// @@@@ SWATDB_ASSIGNMENT: CUT_END
 
    BufferState getBufferState();
 
    std::uint32_t getNumUnpinned();
 
    void printAllFrames();
 
    void printValidFrames();
 
    void printFrame(FrameId frame_id);
 
    void printPage(PageId page_id);
 
    void printBufferState();
 
 
    void printReplacementStats();
 
  private:
 
    BufferMap buf_map;
 
    Frame frame_table[BUF_SIZE];
 
    Page buf_pool[BUF_SIZE];
 
    DiskManager* disk_mgr;
 
    ReplacementPolicy *replacement_pol;
 
    // @@@@ SWATDB_ASSIGNMENT: NOTEMSG you may add private helper methods here
 
    // @@@@ SWATDB_ASSIGNMENT: CUT_START
    std::mutex buf_map_mtx;
    // @@@@ SWATDB_ASSIGNMENT: CUT_END
 
 
    // @@@@ SWATDB_ASSIGNMENT: CUT_START
    FrameId _bufferReplace();
    // @@@@ SWATDB_ASSIGNMENT: CUT_END
 
    void _printFrameHelper(FrameId frame_id);
 
};
 
#endif