Emacs linum-format that works around whitespace-mode and padding

example.el

;; Linum mode
(global-linum-mode t)

;; Custom face/function to pad the line number in a way that does not conflict with whitespace-mode
(defface linum-padding
  `((t :inherit 'linum
       :foreground ,(face-attribute 'linum :background nil t)))
  "Face for displaying leading zeroes for line numbers in display margin."
  :group 'linum)

(defun linum-format-func (line)
  (let ((w (length
            (number-to-string (count-lines (point-min) (point-max))))))
    (concat
     (propertize " " 'face 'linum-padding)
     (propertize (make-string (- w (length (number-to-string line))) ?0)
                 'face 'linum-padding)
     (propertize (number-to-string line) 'face 'linum)
     (propertize " " 'face 'linum-padding)
     )))

(setq linum-format 'linum-format-func)

thanks