(define (warn msg)
  (map
    (lambda (item)
      (display item (current-error-port)))
    `("WARNING: " msg #\newline)))

(define (integer->bytevector value endness size)
  (let ((bytes (make-bytevector size 0)))
    (bytevector-uint-set! bytes 0 value endness size)
    bytes))

(define (get-random-bytes count)
  (letrec*
    ((looper (lambda (result)
               (if (>= (bytevector-length result) count)
                 result
                 (looper
                   (bytevector-append result
                                      (bytevector (random-integer 255))))))))
    (looper (make-bytevector 0))))