How do I show login form to anonymous user when accessing particular form

Question

I have created an entry form. Only authenticated user can access it. I have created a menu link for it and if any anonymous user clicks on menu link I want to show a login form and after successful login user is redirected to that entry form. I don't want to hide the menu link from anonymous user.(I have about 5 to 6 forms with same condition)

Answer 1

Logintoboggan will allow you display a login form when a user hits an access denied page:

Provide a login form on Access Denied pages for non-logged-in (anonymous) users.

Answer 2

?php
          global $user;
          //Redirect original Page
          $redirect = 'destination='.drupal_get_path_alias(substr(urldecode(  drupal_get_destination()), 12) );
          if ($user->uid) 
          {
                        header('Location:?q=node/nodename');   //If user is logged in. Go to specific destination      
          }
         else 
          { 
          //If user is not logged in. Show him login or register
                       $login_link = l(t('Login'), 'user', array( 'query' => $redirect, 'alias' => TRUE )); 
$register_link = l(t('Register'), 'user/register', array( 'query' => $redirect, 'alias' => TRUE ));
$user_utilities = '

' . $login_link . '
' . $register_link;
}
echo "You are not Registered User. Please Login ";
return $user_utilities;
?>