gStore/KVstore/ISTree/ISTree.h

80 lines
2.9 KiB
C++

/*=============================================================================
# Filename: ISTree.h
# Author: syzz
# Mail: 1181955272@qq.com
# Last Modified: 2015-04-26 16:44
# Description: ID2string, including id2entity, id2literal and id2predicate
=============================================================================*/
#ifndef _KVSTORE_ISTREE_ISTREE_H
#define _KVSTORE_ISTREE_ISTREE_H
#include "../../Util/Util.h"
#include "../../Util/Stream.h"
#include "node/ISNode.h"
#include "node/ISIntlNode.h"
#include "node/ISLeafNode.h"
#include "storage/ISStorage.h"
class ISTree
{
protected:
unsigned int height; //0 indicates an empty tree
ISNode* root;
ISNode* leaves_head; //the head of LeafNode-list
ISNode* leaves_tail; //the tail of LeafNode-list
std::string mode; //BETTER(to use enum)
ISStorage* TSM; //Tree-Storage-Manage
//BETTER:multiple stream maybe needed:)
Stream* stream;
//always alloc one more byte than length, then user can add a '\0'
//to get a real string, instead of new and copy
//other operations will be harmful to search, so store value in
//transfer temporally, while length adjusted.
//TODO: in multi-user case, multiple-search will cause problem,
//so lock is a must. Add lock to transfer is better than to add
//lock to every key/value. However, modify requires a lock for a
//key/value, and multiple search for different keys are ok!!!
Bstr transfer[3]; //0:transfer value searched; 1:copy key-data from const char*; 2:copy val-data from const char*
unsigned transfer_size[3];
//tree's operations should be atom(if read nodes)
//sum the request and send to ISStorage at last
//ensure that all nodes operated are in memory
long long request;
void prepare(ISNode* _np);
std::string storepath;
std::string filename; //ok for user to change
/* some private functions */
std::string getFilePath(); //in UNIX system
void CopyToTransfer(const char* _str, unsigned _len, unsigned _index);
void release(ISNode* _np) const;
public:
ISTree(); //always need to initial transfer
ISTree(std::string _storepath, std::string _filename, std::string _mode, unsigned long long _buffer_size);
unsigned int getHeight() const;
void setHeight(unsigned _h);
ISNode* getRoot() const;
//void setRoot(Node* _root);
//insert, search, remove, set
bool search(int _key, char*& _str, int& _len);
bool insert(int _key, const char* _str, unsigned _len);
bool modify(int _key, const char* _str, unsigned _len);
ISNode* find(int _key, int* store, bool ifmodify);
bool remove(int _key);
const Bstr* getRangeValue();
void resetStream();
bool range_query(int _key1, int _key2);
bool save();
~ISTree();
void print(std::string s); //DEBUG(print the tree)
};
//NOTICE: need to save tree manually before delete, otherwise will cause problem.
//(problem range between two extremes: not-modified, totally-modified)
//After saved, it's ok to continue operations on tree!
#endif