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/* 	SQL Klasse zum Zugriff auf mysql Datenbanken mit C++.
 *  
  */
 
#ifndef SQL_H
#define SQL_H
 
#define MAX_IRC_TEXT_LENGHT 512
#define STEP				8
 
#include <iostream>
#include <mysql.h>
#include <string>
 
using namespace std;
 
class sql {
private:
	char *pHost;
	int pHost_sz;
 
	char *pUser;
	int pUser_sz;
 
	char *pPw;
	int pPw_sz;
 
	char *pDb;
	int pDb_sz;
 
	bool connected;
 
	void sql_init();
	void sql_error();
	bool sql_connect();
	void sql_disconnect();
 
public:
	// Das MYSQL Objekt aus der mysql.h
	MYSQL *my;
 
	// Konstruktor / Destruktor
	sql(char *_host, char *_user, char *_pw, char *_db);
	~sql();
 
	// Methoden
 
	// debugging Methode
	void DEBUG();
 
	// Verbindung aufbauen
 
	// Query ausführen
	bool sql_query(string query);
};
 
// Konstruktor
sql::sql(char *_host, char *_user, char *_pw, char *_db) {
	this->pHost = NULL;
	this->pHost_sz = 0;
 
	this->pUser = NULL;
	this->pUser_sz = 0;
 
	this->pPw = NULL;
	this->pPw_sz = 0;
 
	this->pDb = NULL;
	this->pDb_sz = 0;
 
	for(int i=0; i<=strlen(_host); i++) {
		if(i >= pHost_sz) {
			char *c = new char[this->pHost_sz+STEP];
 
			for(int j=0; j<pHost_sz; j++) {
				c[j] = this->pHost[j];	
			}	
 
			if(this->pHost == NULL)
				delete[] this->pHost;
 
			this->pHost = c;
			this->pHost_sz += STEP;	
 
		}
		this->pHost[i] = _host[i];
	}
 
 
	for(int i=0; i<=strlen(_user); i++) {
		if(i >= pUser_sz) {
			char *c = new char[this->pUser_sz+STEP];
 
			for(int j=0; j<pUser_sz; j++) {
				c[j] = this->pUser[j];	
			}	
 
			if(this->pUser == NULL)
				delete[] this->pUser;
 
			this->pUser = c;
			this->pUser_sz += STEP;	
		}
		this->pUser[i] = _user[i];
	}
 
 
	for(int i=0; i<=strlen(_pw); i++) {
		if(i >= pPw_sz) {
			char *c = new char[this->pPw_sz+STEP];
 
			for(int j=0; j<pPw_sz; j++) {
				c[j] = this->pPw[j];	
			}	
 
			if(this->pPw == NULL)
				delete[] this->pPw;
 
			this->pPw = c;
			this->pPw_sz += STEP;	
		}
		this->pPw[i] = _pw[i];
	}
 
 
	for(int i=0; i<=strlen(_db); i++) {
		if(i >= pDb_sz) {
			char *c = new char[this->pDb_sz+STEP];
 
			for(int j=0; j<pDb_sz; j++) {
				c[j] = this->pDb[j];	
			}	
 
			if(this->pDb == NULL)
				delete[] this->pDb;
 
			this->pDb = c;
			this->pDb_sz += STEP;	
		}
		this->pDb[i] = _db[i];
	}
 
	// Nachdem die Parameter gesetzt wurden, wird das Objekt initialisiert
	this->sql_init();
}
 
sql::~sql() {
	if(this->pHost != NULL) {
		delete[] pHost;
	}
	if(this->pUser != NULL) {
		delete[] pUser;
	}
	if(this->pPw != NULL) {
		delete[] pPw;
	}
	if(this->pDb != NULL) {
		delete[] pDb;
	}
}
 
void sql::sql_error() {
	// Selbsterklärend
	cerr << "Errorcode: " << mysql_errno(my) << "\n" << mysql_error(my);
	//exit(EXIT_FAILURE);
}
 
void sql::DEBUG() {
	cout << this->pHost << endl;
	cout << this->pUser << endl;
	cout << this->pPw << endl;
	cout << this->pDb << endl;
}
 
void sql::sql_init() {
	this->connected = false;
 
	if((this->my = mysql_init(NULL)) == NULL) {
		cerr << "Fehler beim initialisieren.";
		exit(EXIT_FAILURE);
	}
}
 
void sql::sql_disconnect() {
	if(this->connected) {
		mysql_close(my);
		this->connected = false;	
	}
}
 
bool sql::sql_connect() {
	// Zur Datenbank verbinden:
	if(this->connected == false) {
		if(mysql_real_connect(
				my,		/* *MYSQL Handler	*/
				this->pHost,	/* Host			*/
				this->pUser,	/* User			*/
				this->pPw,	/* Passwort		*/
				this->pDb,	/* Datenbank	*/
				0,			/* Port			*/
				NULL,		/* Socket		*/
				0)			/* Flags 		*/ == NULL) {
			// Bei einem Fehler die error Methode ausführen
			this->sql_error();
			return false;
		}
		else {
			this->connected = true;
			return true;
		}	
	}
 
}
 
bool sql::sql_query(string query) {
 
	if(this->connected == false) {
		if(this->sql_connect() == false) {
			return false;
		}
	}
 
	// in dynamic char casten
	char *sql_char = NULL;
	int sql_char_sz = 0;
	for(int i=0; i<=query.size(); i++) {
		// Ist das Query länger als der sql_char?
		if(i >= sql_char_sz) {
			// Joa, ist er, also ein neues - größeres - Char erzeugen
			char *c = new char[sql_char_sz+STEP];
			// Daten kopieren
			for(int j=0; j<sql_char_sz; j++)
				c[j] = sql_char[j];
			// Altes Char löschen
			if(sql_char != NULL)
				delete[] sql_char;
			// c zuweisen
			sql_char = c;
			sql_char_sz += STEP;
		}
		// Dateneintragen
		sql_char[i] = query[i];
	}
 
	// Query ausführen
	if(mysql_real_query(this->my, sql_char, (unsigned) (long) strlen(sql_char)))
		this->sql_error();
 
	if(this->connected == true) {
		this->sql_disconnect();	
	}
 
	return true;
}
 
#endif