route.php

<?php

$routes = array(    
 '/hello' => 'hello.php',
 '/user' => 'listar_usuario.php',
 '/user/add' => 'adicionar_usuario.php'
);

function router($routes) {
  // Iterate atraves da lista de rotas e faz include
    foreach ($routes as $path => $include)
        if ($path == $_SERVER['PATH_INFO']) {            
            return require $include;
        }       
    echo 'Desculpe, pagina nao encontrada.';
}