AllocationPage.h

/*
 * AllocationPage.h
 *
 *  Created on: Mar 24, 2010
 *      Author: green
 */

#ifndef ALLOCATIONPAGE_H_
#define ALLOCATIONPAGE_H_

#include "Common.h"
#include <limits.h>

class AllocationPage {
public:
        AllocationPage();
        ~AllocationPage();
        int getFirstPage(bool isFree);
        int getLastPage(bool isFree);
        int getNextPage(int pageNo, bool isFree);
        int getPrevPage(int pageNo, bool isFree);
        bool isPageFree(int pageNo);
        ReturnCode markPageFree(int pageNo, bool isFree);
        uint getAllocatedPageCount();

        ReturnCode serialize(char *buffer);
        static ReturnCode deserialize(const char* buffer, AllocationPage* page);

        static const uint VERSION = 2;
        static const int BITMAP_SIZE = PF_PAGE_SIZE - sizeof(uint);
        static const int RANGE_SIZE = BITMAP_SIZE*CHAR_BIT;

private:
        bool testBit(int byte, int bitNo, bool isFree);
        int getNeighborBit(int bitNo, uchar byte, bool isFree, bool isNext);
        int getNeighborPage(int pageNo, bool isFree, bool isNext);
        uint versionNo_;
        uchar bitmap_[BITMAP_SIZE];
};

#endif /* ALLOCATIONPAGE_H_ */

---