Thread: Problem

hey,

The following code is suppossed to allow someone to type in a username and password and it would log in. I ran into a big problem though that I can't figure out what the problem is. It's probably something simple but I can't figure it out.

Everything works right up until the part where I put comments (//HERE). It doesn't seem to work, it always skips the if statement even if the passwords do not mach...

Code:

void login()
{
     //Test Variables
     char testaccname[50];
     char testaccpass[50];
     char buffer[50];
     
     //Display Title
     cout<<endl <<endl <<"Login\n";
     cout<<"---------------------------\n";
     
     //Get Account Name
     accname:
     cout<<"Account Name: ";
     cin.getline ( testaccname, 50 );
     
     //Check To See If Account Name Exists
     ifstream test_file ( testaccname );
     if (! test_file.is_open() ) {
          cout<<"Invalid Account Name!\n" <<endl;
          goto accname;
     }
     
     //Get Password From File
     test_file.getline( buffer, 50 );
     test_file.getline( buffer, 50 );
     accpass:
     cout<<"Account Password: ";
     cin.getline( testaccpass, 50 );
     

     //HERE
     if (! buffer == testaccpass ) {          
         cout<<"Invalid Password!\n" <<endl;
         goto accpass;  
     }
     //HERE


     cout<<"Login Success!\n";
     getch();
     return;
}

Thanks.
Anthony

Use strcmp(), not ==.

strcmp(c-string_1, c-string_2) will return 0 if the two strings are equal.

Code:

void login()
{
     //Test Variables
     char testaccname[50];
     char testaccpass[50];
     char buffer[50];
     
     //Display Title
     cout<<endl <<endl <<"Login\n";
     cout<<"---------------------------\n";
     
     //Get Account Name
     accname:
     cout<<"Account Name: ";
     cin.getline ( testaccname, 50 );
     
     //Check To See If Account Name Exists
     ifstream test_file ( testaccname );
     if (! test_file.is_open() ) {
          cout<<"Invalid Account Name!\n" <<endl;
          goto accname;
     }
     
     //Get Password From File
     test_file.getline( buffer, 50 );
     test_file.getline( buffer, 50 );
     accpass:
     cout<<"Account Password: ";
     cin.getline( testaccpass, 50 );
     

     //HERE
      if (!strcmp(buffer, testaccpass) ==0){          
         cout<<"Invalid Password!\n" <<endl;
         goto accpass;  
     }
     //HERE


     cout<<"Login Success!\n";
     getch();
     return;
}

Also i dont know who's been teaching you but your use of goto is a bit overboard considering there are better way's of doing it.
If you cant write a simple 20 line program without 'goto' your going to have problems when you start writing larger programs.

Originally Posted by Zach L.

Code:

if (strcmp(buffer, testaccpass) == 0)

It returns 0 if true. So if strcmp() == 0, then the strings are the same. You'd want !=, not ==, in that statement.

very easy to crack