<?php
//Checks a given Username & Password combo.
function validate_credentials($user_name, $user_password){
	$user_name = mysql_real_escape_string($user_name);
	$user_password sha1($user_password);

	$result = mysql_query("SELECT 'user_id' FROM 'users' WHERE 'user_name' = '{$user_name}' AND 'user_password' = '{$user_password}'");

	if (mysql_num_rows($result) != 1){
		return false;
	}
	return mysql_result($result, 0); //return ID.

}

?>