Problem connecting to MySQL Database?

Ok, I almost finished my program, but there's one little problem.

This is the code:

request.h

Code:

// Create prototype from Request class
class Request
{
      public:
             Request();
             ~Request();
             
             // Main function
             bool handle_requests();
             
             // MySQL Functions
             bool connect_to_db();
             
      protected:             
             // Winamp vars
             WINAMPCOMLib::IApplicationPtr winamp;
             
             // MySQL vars
             MYSQL * mysql_conn;
             MYSQL_RES * result;
             MYSQL_ROW row;
             
};

main.cpp

Code:

#include <windows.h>
#include <mysql.h>
#include <iostream>
#include <stdio.h>

#pragma comment(lib, "D:\\server\\mysql\\lib\\opt\\libmysql.lib")

#import "c:\program files\winamp\plugins\gen_com.dll"
#include "request.h"

using namespace std;

Request::Request()
{
	cout << "Create winamp instance" << endl;
	// Create winamp instance
	Request::winamp.CreateInstance(__uuidof(WINAMPCOMLib::Application));
	
	cout << "Done." << endl;			
}
Request::~Request()
{
	mysql_close(Request::mysql_conn);
}

bool Request::connect_to_db()
{
	cout << "Connecting to Database..." << endl;
	mysql_init(Request::mysql_conn);
	if(!mysql_real_connect(Request::mysql_conn, "localhost", "lucas", "***", "luckyradio", 0, NULL, 0))
	{
		cout << "Could not connect to database:\n" << mysql_error(Request::mysql_conn) << endl;
		return false;
	}
	
	cout << "Done." << endl;
	return true;
}

bool Request::handle_requests()
{
	cout << "Started Winamp Request Handler" << endl;
	while(true)
	{
		if(!Request::winamp->CurrentPos)
		{
			if(!mysql_query(Request::mysql_conn, "SELECT * FROM e107_wa_request ORDER BY request_id ASC LIMIT 1"))
			{
				cout << "Error in selecting requests:\n" << mysql_error(Request::mysql_conn) << endl;
				return false;
			}
			
			result = mysql_use_result(Request::mysql_conn);
			row = mysql_fetch_row(result);
			
			long playlist_pos = reinterpret_cast<long>(row[1]);
			
			Request::winamp->put_PlayListPos(playlist_pos);
			Request::winamp->Play();
			
			cout << "Requesting: " << Request::winamp->GetSongTitle(playlist_pos) << "..." << endl;  						
		}
	}
	
	return false;
}

int main()
{
	Request request;
	if(request.connect_to_db())
	{
		request.handle_requests();
	
		cin.get();
	}
	
	return 1;
}

I compile it with Visual C++ 2005 Express edition, and no errors appear. Compile succesfull

But, when I try to start the program, I get this:

http://www.aoe3capitol.nl/images/requester_error.png

Does anyone know how I can fix this?

I dont use this API (I use ADO & ADO.NET), but I think you are not allocating space for the connection struct...

Try

Code:

MYSQL mysql_conn;

....


mysql_init(&Request::mysql_conn);
	if(!mysql_real_connect(&Request::mysql_conn, "localhost", "lucas", "***", "luckyradio", 0, NULL, 0))

Ah fixed it,

It should be:

Code:

bool Request::connect_to_db()
{
	cout << "Connecting to Database..." << endl;
	Request::mysql_conn = mysql_init(NULL);
	if(!mysql_real_connect(Request::mysql_conn, "localhost", "lucas", "***", "luckyradio", 0, NULL, 0))
	{
		cout << "Could not connect to database:\n" << mysql_error(Request::mysql_conn) << endl;
		return false;
	}
	
	cout << "Done." << endl;
	return true;
}

Try dump the "Request::" as it's part of the same class it shouldnt be needed

Also where you had "Request::mysql_conn" in your original code, it should be "&mysql_conn";

Fixed above problem, but I get now another error:

http://www.aoe3capitol.nl/images/requester_error2.png

Current Code:

request.h

Code:

// Create prototype from Request class
class Request
{
      public:
             Request();
             ~Request();
             
             // Main function
             bool handle_requests();
             
             // MySQL Functions
             bool connect_to_db();
             
      protected:             
             // Winamp vars
             WINAMPCOMLib::IApplicationPtr winamp;
             
             // MySQL vars
             MYSQL * mysql_conn;
             MYSQL_RES * result;
             MYSQL_ROW row;
             
};

main.cpp

Code:

#include <windows.h>
#include <mysql.h>
#include <iostream>
#include <stdio.h>

#pragma comment(lib, "D:\\server\\mysql\\lib\\opt\\libmysql.lib")

#import "c:\program files\winamp\plugins\gen_com.dll"
#include "request.h"

using namespace std;

Request::Request()
{
	cout << "Create winamp instance..." << endl;
	// Create winamp instance
	Request::winamp.CreateInstance(__uuidof(WINAMPCOMLib::Application));
	
	cout << "Done." << endl;			
}
Request::~Request()
{
	mysql_close(Request::mysql_conn);
}

bool Request::connect_to_db()
{
	cout << "Connecting to Database..." << endl;
	Request::mysql_conn = mysql_init(NULL);
	if(!mysql_real_connect(Request::mysql_conn, "localhost", "lucas", "***", "luckyradio", 0, NULL, 0))
	{
		cout << "Could not connect to database:\n" << mysql_error(Request::mysql_conn) << endl;
		return false;
	}
	
	cout << "Done." << endl;
	return true;
}

bool Request::handle_requests()
{
	cout << "Winamp Request Handler started." << endl;
	while(true)
	{
		if(!Request::winamp->CurrentPos)
		{
			if(!mysql_query(Request::mysql_conn, "SELECT * FROM e107_wa_request ORDER BY request_id ASC LIMIT 1"))
			{
				cout << "Error in selecting requests:\n" << mysql_error(Request::mysql_conn) << endl;
				return false;
			}
			
			result = mysql_use_result(Request::mysql_conn);
			Request::row = mysql_fetch_row(result);
			
			long playlist_pos = reinterpret_cast<long>(row[1]);
			
			Request::winamp->put_PlayListPos(playlist_pos);
			Request::winamp->Play();
			
			cout << "Requesting: " << Request::winamp->GetSongTitle(playlist_pos) << "..." << endl;  						
		}
	}
	
	return false;
}

int main()
{
	cout << "Starting winamp Request handler...." << endl;
	
	Request request;
	if(request.connect_to_db())
	{
		request.handle_requests();
	
		cin.get();
	}
	
	return 1;
}

Nobody?