lisp/mail/rfc2368.el

   1 ;;; rfc2368.el --- support for rfc2368
   2
   3 ;; Copyright (C) 1998, 2000, 2001, 2002, 2003, 2004,
   4 ;;   2005, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
   5
   6 ;; Author: Sen Nagata <sen@eccosys.com>
   7 ;; Keywords: mail
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software: you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation, either version 3 of the License, or
  14 ;; (at your option) any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25 ;;
  26 ;; notes:
  27 ;;
  28 ;;   -repeat after me: "the colon is not part of the header name..."
  29 ;;   -if w3 becomes part of emacs, then it may make sense to have this
  30 ;;    file depend on w3 -- the maintainer of w3 says merging w/ Emacs
  31 ;;    is planned!
  32 ;;
  33 ;; historical note:
  34 ;;
  35 ;;   this is intended as a replacement for mailto.el
  36 ;;
  37 ;; acknowledgements:
  38 ;;
  39 ;;   the functions that deal w/ unhexifying in this file were basically
  40 ;; taken from w3 -- i hope to replace them w/ something else soon OR
  41 ;; perhaps if w3 becomes a part of emacs soon, use the functions from w3.
  42
  43 ;;; History:
  44 ;;
  45 ;; 0.3:
  46 ;;
  47 ;;  added the constant rfc2368-version
  48 ;;  implemented first potential fix for a bug in rfc2368-mailto-regexp
  49 ;;  implemented first potential fix for a bug in rfc2368-parse-mailto
  50 ;;  (both bugs reported by Kenichi OKADA)
  51 ;;
  52 ;; 0.2:
  53 ;;
  54 ;;  started to use checkdoc
  55 ;;
  56 ;; 0.1:
  57 ;;
  58 ;;  initial implementation
  59
  60 ;;; Code:
  61
  62 ;; only an approximation?
  63 ;; see rfc 1738
  64 (defconst rfc2368-mailto-regexp
  65   "^\\(mailto:\\)\\([^?]+\\)*\\(\\?\\(.*\\)\\)*"
  66   "Regular expression to match and aid in parsing a mailto url.")
  67
  68 ;; describes 'mailto:'
  69 (defconst rfc2368-mailto-scheme-index 1
  70   "Describes the 'mailto:' portion of the url.")
  71 ;; i'm going to call this part the 'prequery'
  72 (defconst rfc2368-mailto-prequery-index 2
  73   "Describes the portion of the url between 'mailto:' and '?'.")
  74 ;; i'm going to call this part the 'query'
  75 (defconst rfc2368-mailto-query-index 4
  76   "Describes the portion of the url after '?'.")
  77
  78 (defun rfc2368-unhexify-string (string)
  79   "Unhexify STRING -- e.g. 'hello%20there' -> 'hello there'."
  80   (replace-regexp-in-string "%[[:xdigit:]]\\{2\\}"
  81                             (lambda (match)
  82                               (string (string-to-number (substring match 1)
  83                                                         16)))
  84                             string t t))
  85
  86 (defun rfc2368-parse-mailto-url (mailto-url)
  87   "Parse MAILTO-URL, and return an alist of header-name, header-value pairs.
  88 MAILTO-URL should be a RFC 2368 (mailto) compliant url.  A cons cell w/ a
  89 key of 'Body' is a special case and is considered a header for this purpose.
  90 The returned alist is intended for use w/ the `compose-mail' interface.
  91 Note: make sure MAILTO-URL has been 'unhtmlized' (e.g. &amp; -> &), before
  92 calling this function."
  93   (let ((case-fold-search t)
  94         prequery query headers-alist)
  95     (setq mailto-url (replace-regexp-in-string "\n" " " mailto-url))
  96     (if (string-match rfc2368-mailto-regexp mailto-url)
  97         (progn
  98           (setq prequery
  99                 (match-string rfc2368-mailto-prequery-index mailto-url))
 100           (setq query
 101                 (match-string rfc2368-mailto-query-index mailto-url))
 102
 103           ;; build alist of header name-value pairs
 104           (if (not (null query))
 105               (setq headers-alist
 106                     (mapcar
 107                      (lambda (x)
 108                        (let* ((temp-list (split-string x "="))
 109                               (header-name (car temp-list))
 110                               (header-value (cadr temp-list)))
 111                          ;; return ("Header-Name" . "header-value")
 112                          (cons
 113                           (capitalize (rfc2368-unhexify-string header-name))
 114                           (rfc2368-unhexify-string header-value))))
 115                      (split-string query "&"))))
 116
 117           ;; deal w/ multiple 'To' recipients
 118           (if prequery
 119               (progn
 120                 (setq prequery (rfc2368-unhexify-string prequery))
 121                 (if (assoc "To" headers-alist)
 122                     (let* ((our-cons-cell
 123                             (assoc "To" headers-alist))
 124                            (our-cdr
 125                             (cdr our-cons-cell)))
 126                       (setcdr our-cons-cell (concat prequery ", " our-cdr)))
 127                   (setq headers-alist
 128                         (cons (cons "To" prequery) headers-alist)))))
 129
 130           headers-alist)
 131
 132       (error "Failed to match a mailto: url"))))
 133
 134 (provide 'rfc2368)
 135
 136 ;;; rfc2368.el ends here