Custom callback functions to execute on user login.

midd-wpcas.php

// this function gets executed 
// if the CAS username doesn't match a username in WordPress
function wpcas_nowpuser( $user_name ) {
	midd_wpcas_nowpuser($user_name);
	// Authenticate again now that the user exists
	$wpCAS = new wpCAS;
	$wpCAS->authenticate();
}
function midd_wpcas_nowpuser($username) {
	require_once( ABSPATH . WPINC . '/registration.php' );
	
	$email = phpCAS::getAttribute('EMail');
	if (!preg_match('/^.+@.+$/', $email)) {
		var_dump(phpCAS::getAttributes());
		die('No valid email, could not provision account.');
	}
	
	$user_id = wpmu_create_user($username, md5(rand().$username), $email);
	
	$firstName = phpCAS::getAttribute('FirstName');
	$lastName = phpCAS::getAttribute('LastName');
	
	preg_match('/^(.+)@(.+)$/', $email, $matches);
	$emailUser = $matches[1];
	$emailDomain = $matches[2];
	if (!$firstName && !$lastName) {
		$lastName = $emailUser;
	}
	
// 	$displayName = trim($firstName.' '.$lastName.' ('.$emailDomain.')');
	$displayName = trim($firstName.' '.$lastName);
	
	if ($login = phpCAS::getAttribute('Login'))
		$nicename = $login;
	else
		$nicename = $emailUser;
	
	$data = array();
	$data['ID'] 			= $user_id;
	$data['user_login']		= $username;
	$data['user_email']		= $email;
	$data['user_nicename']	= $nicename;
	$data['nickname']		= $nicename;
	$data['display_name']	= $displayName;
	$data['first_name']		= $firstName;
	$data['last_name']		= $lastName;
	wp_update_user($data);
	
	// If we wish to provision a site for the user, now would be the time to do it.
	
}