diff options
Diffstat (limited to 'lisp/url/url-util.el')
| -rw-r--r-- | lisp/url/url-util.el | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/lisp/url/url-util.el b/lisp/url/url-util.el index 85bfb65cb68..ffae984941e 100644 --- a/lisp/url/url-util.el +++ b/lisp/url/url-util.el @@ -627,6 +627,34 @@ Creates FILE and its parent directories if they do not exist." (error "Danger: `%s' is a symbolic link" file)) (set-file-modes file #o0600)))) +(autoload 'puny-encode-domain "puny") +(autoload 'url-domsuf-cookie-allowed-p "url-domsuf") + +;;;###autoload +(defun url-domain (url) + "Return the domain of the host of the URL. +Return nil if this can't be determined. + +For instance, this function will return \"fsf.co.uk\" if the host in URL +is \"www.fsf.co.uk\"." + (let* ((host (puny-encode-domain (url-host url))) + (parts (nreverse (split-string host "\\."))) + (candidate (pop parts)) + found) + ;; IP addresses aren't domains. + (when (string-match "\\`[0-9.]+\\'" host) + (setq parts nil)) + ;; We assume that the top-level domain is never an appropriate + ;; thing as "the domain", so we start at the next one (eg. + ;; "fsf.org"). + (while (and parts + (not (setq found + (url-domsuf-cookie-allowed-p + (setq candidate (concat (pop parts) "." + candidate)))))) + ) + (and found candidate))) + (provide 'url-util) ;;; url-util.el ends here |