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? :(