gStore/KVstore/IVArray/IVEntry.h

/*=======================================================================
 * File name: IVEntry.h
 * Author: Zongyue Qin
 * Mail: qinzongyue@pku.edu.cn
 * Last Modified: 2018-01-30
 * Description: head file of IVEntry, the most basic unit of IVArray
 * =====================================================================*/

#include "../../Util/Util.h"
#include "../../Util/VList.h"

using namespace std;

class IVEntry
{
	bool usedFlag;   // mark if the entry is used
	bool dirtyFlag;
	bool cacheFlag;
	bool CachePinFlag;
	unsigned store;  //index of block where value is stored
	// pointer to id for LRU list
	int prevID;
	int nextID;

	Bstr* value;

public:
	IVEntry();
	
	void setBstr(const Bstr* _value);
	bool getBstr(char *& _str, unsigned& _len, bool if_copy = true) const;
	void setBstr(char *_str, unsigned _len);
	
	void setStore(unsigned _store);
	unsigned getStore() const;

	void setUsedFlag(bool _flag);
	bool isUsed() const;

	void setDirtyFlag(bool _flag);
	bool isDirty() const;
	
	void setCacheFlag(bool _flag);
	bool inCache() const;

	void setCachePinFlag(bool _flag);
	bool isPined();

	void release();

	void Copy(const IVEntry& _entry);

	void setPrev(int ID);
	int getPrev() const;
	void setNext(int ID);
	int getNext() const;

	~IVEntry();
};