lisp/url/url-about.el

   1 ;;; url-about.el --- Show internal URLs
   2
   3 ;; Copyright (C) 2001, 2004-2017 Free Software Foundation, Inc.
   4
   5 ;; Keywords: comm, data, processes, hypermedia
   6
   7 ;; This file is part of GNU Emacs.
   8 ;;
   9 ;; GNU Emacs is free software: you can redistribute it and/or modify
  10 ;; it under the terms of the GNU General Public License as published by
  11 ;; the Free Software Foundation, either version 3 of the License, or
  12 ;; (at your option) any later version.
  13
  14 ;; GNU Emacs is distributed in the hope that it will be useful,
  15 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 ;; GNU General Public License for more details.
  18
  19 ;; You should have received a copy of the GNU General Public License
  20 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  21
  22 ;;; Commentary:
  23
  24 ;;; Code:
  25
  26 (require 'url-util)
  27 (require 'url-parse)
  28
  29 (defun url-probe-protocols ()
  30   "Return a list of all potential URL schemes."
  31   (or (get 'url-extension-protocols 'probed)
  32       (mapc (lambda (s) (url-scheme-get-property s 'name))
  33             (or (get 'url-extension-protocols 'schemes)
  34                 (let ((schemes '("info" "man" "rlogin" "telnet"
  35                                  "tn3270" "data" "snews")))
  36                   (mapc (lambda (d)
  37                           (mapc (lambda (f)
  38                                   (if (string-match "url-\\(.*\\).el$" f)
  39                                       (push (match-string 1 f) schemes)))
  40                                 (directory-files d nil "^url-.*\\.el$")))
  41                         load-path)
  42                   (put 'url-extension-protocols 'schemes schemes)
  43                   schemes)))))
  44
  45 (defvar url-scheme-registry)
  46
  47 (defun url-about-protocols (url)
  48   (url-probe-protocols)
  49   (insert "<html>\n"
  50           " <head>\n"
  51           "  <title>Supported Protocols</title>\n"
  52           " </head>\n"
  53           " <body>\n"
  54           "  <h1>Supported Protocols - URL v" url-version "</h1>\n"
  55           "  <table width='100%' border='1'>\n"
  56           "   <tr>\n"
  57           "    <td>Protocol\n"
  58           "    <td>Properties\n"
  59           "    <td>Description\n"
  60           "   </tr>\n")
  61   (mapc (lambda (k)
  62           (if (string= k "proxy")
  63               ;; Ignore the proxy setting... its magic!
  64               nil
  65             (insert "   <tr>\n")
  66             ;; The name of the protocol
  67             (insert "    <td valign=top>" (or (url-scheme-get-property k 'name) k) "\n")
  68
  69             ;; Now the properties.  Currently just asynchronous
  70             ;; status, default port number, and proxy status.
  71             (insert "    <td valign=top>"
  72                     (if (url-scheme-get-property k 'asynchronous-p) "As" "S")
  73                     "ynchronous<br>\n"
  74                     (if (url-scheme-get-property k 'default-port)
  75                         (format "Default Port: %d<br>\n"
  76                                 (url-scheme-get-property k 'default-port)) "")
  77                     (if (assoc k url-proxy-services)
  78                         (format "Proxy: %s<br>\n" (assoc k url-proxy-services)) ""))
  79             ;; Now the description...
  80             (insert "    <td valign=top>"
  81                     (or (url-scheme-get-property k 'description) "N/A"))))
  82         (sort (let (x) (maphash (lambda (k v) (push k x)) url-scheme-registry) x) 'string-lessp))
  83   (insert "  </table>\n"
  84           " </body>\n"
  85           "</html>\n"))
  86
  87 (defun url-about (url)
  88   "Show internal URLs."
  89   (let* ((item (downcase (url-filename url)))
  90          (func (intern (format "url-about-%s" item))))
  91     (if (fboundp func)
  92         (progn
  93           (set-buffer (generate-new-buffer " *about-data*"))
  94           (insert "Content-type: text/plain\n\n")
  95           (funcall func url)
  96           (current-buffer))
  97       (error "URL does not know about `%s'" item))))
  98
  99 (provide 'url-about)
 100
 101 ;;; url-about.el ends here