(in-package :net/util)

 (defvar *localhost* #(127 0 0 1))

 ;; from usocket

 (defun get-address-by-name (name)

   "Return the address of a host by NAME."

   (multiple-value-bind (host4 host6)

       (get-host-by-name name)

     (let ((addr4 (when host4

                    (car (sb-bsd-sockets::host-ent-addresses host4))))

           (addr6 (when host6

                    (car (sb-bsd-sockets::host-ent-addresses host6)))))

       (values addr4 addr6))))

 ;; from https://github.com/eudoxia0/find-port

 (defun port-open-p (port &key (host *localhost*))

   "Determine if a PORT is open on the given HOST."

   (handler-case

       (let ((socket (make-instance 'inet-socket :type :stream)))

         (setf (sockopt-reuse-address socket) t)

         (socket-bind socket host port)

         (socket-close socket))

     (address-in-use-error (condition)

       (declare (ignore condition))

       nil)))

 (defun find-port (&key (min 32000) (max 48000) (host *localhost*))

   "Return the first available port in a range of port numbers."

   (loop :for port :from min :to max :when (port-open-p port :host host) :return port))

 ;; (get-address-by-name "localhost")