lisp/mail/rfc2368.el

   1 ;;; rfc2368.el --- support for rfc2368
   2
   3 ;; Copyright (C) 1998, 2000, 2001, 2002, 2003, 2004,
   4 ;;   2005, 2006, 2007 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 2, or (at your option)
  14 ;; 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; see the file COPYING.  If not, write to the
  23 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  24 ;; Boston, MA 02110-1301, USA.
  25
  26 ;;; Commentary:
  27 ;;
  28 ;; notes:
  29 ;;
  30 ;;   -repeat after me: "the colon is not part of the header name..."
  31 ;;   -if w3 becomes part of emacs, then it may make sense to have this
  32 ;;    file depend on w3 -- the maintainer of w3 says merging w/ Emacs
  33 ;;    is planned!
  34 ;;
  35 ;; historical note:
  36 ;;
  37 ;;   this is intended as a replacement for mailto.el
  38 ;;
  39 ;; acknowledgements:
  40 ;;
  41 ;;   the functions that deal w/ unhexifying in this file were basically
  42 ;; taken from w3 -- i hope to replace them w/ something else soon OR
  43 ;; perhaps if w3 becomes a part of emacs soon, use the functions from w3.
  44
  45 ;;; History:
  46 ;;
  47 ;; 0.3:
  48 ;;
  49 ;;  added the constant rfc2368-version
  50 ;;  implemented first potential fix for a bug in rfc2368-mailto-regexp
  51 ;;  implemented first potential fix for a bug in rfc2368-parse-mailto
  52 ;;  (both bugs reported by Kenichi OKADA)
  53 ;;
  54 ;; 0.2:
  55 ;;
  56 ;;  started to use checkdoc
  57 ;;
  58 ;; 0.1:
  59 ;;
  60 ;;  initial implementation
  61
  62 ;;; Code:
  63
  64 ;; only an approximation?
  65 ;; see rfc 1738
  66 (defconst rfc2368-mailto-regexp
  67   "^\\(mailto:\\)\\([^?]+\\)*\\(\\?\\(.*\\)\\)*"
  68   "Regular expression to match and aid in parsing a mailto url.")
  69
  70 ;; describes 'mailto:'
  71 (defconst rfc2368-mailto-scheme-index 1
  72   "Describes the 'mailto:' portion of the url.")
  73 ;; i'm going to call this part the 'prequery'
  74 (defconst rfc2368-mailto-prequery-index 2
  75   "Describes the portion of the url between 'mailto:' and '?'.")
  76 ;; i'm going to call this part the 'query'
  77 (defconst rfc2368-mailto-query-index 4
  78   "Describes the portion of the url after '?'.")
  79
  80 (defun rfc2368-unhexify-string (string)
  81   "Unhexify STRING -- e.g. 'hello%20there' -> 'hello there'."
  82   (replace-regexp-in-string "%[[:xdigit:]]\\{2\\}"
  83                             (lambda (match)
  84                               (string (string-to-number (substring match 1)
  85                                                         16)))
  86                             string t t))
  87
  88 (defun rfc2368-parse-mailto-url (mailto-url)
  89   "Parse MAILTO-URL, and return an alist of header-name, header-value pairs.
  90 MAILTO-URL should be a RFC 2368 (mailto) compliant url.  A cons cell w/ a
  91 key of 'Body' is a special case and is considered a header for this purpose.
  92 The returned alist is intended for use w/ the `compose-mail' interface.
  93 Note: make sure MAILTO-URL has been 'unhtmlized' (e.g. &amp; -> &), before
  94 calling this function."
  95   (let ((case-fold-search t)
  96         prequery query headers-alist)
  97
  98     (if (string-match rfc2368-mailto-regexp mailto-url)
  99         (progn
 100
 101           (setq prequery
 102                 (match-string rfc2368-mailto-prequery-index mailto-url))
 103
 104           (setq query
 105                 (match-string rfc2368-mailto-query-index mailto-url))
 106
 107           ;; build alist of header name-value pairs
 108           (if (not (null query))
 109               (setq headers-alist
 110                     (mapcar
 111                      (lambda (x)
 112                        (let* ((temp-list (split-string x "="))
 113                               (header-name (car temp-list))
 114                               (header-value (cadr temp-list)))
 115                          ;; return ("Header-Name" . "header-value")
 116                          (cons
 117                           (capitalize (rfc2368-unhexify-string header-name))
 118                           (rfc2368-unhexify-string header-value))))
 119                      (split-string query "&"))))
 120
 121           ;; deal w/ multiple 'To' recipients
 122           (if prequery
 123               (progn
 124                 (setq prequery (rfc2368-unhexify-string prequery))
 125                 (if (assoc "To" headers-alist)
 126                     (let* ((our-cons-cell
 127                             (assoc "To" headers-alist))
 128                            (our-cdr
 129                             (cdr our-cons-cell)))
 130                       (setcdr our-cons-cell (concat prequery ", " our-cdr)))
 131                   (setq headers-alist
 132                         (cons (cons "To" prequery) headers-alist)))))
 133
 134           headers-alist)
 135
 136       (error "Failed to match a mailto: url"))
 137     ))
 138
 139 (provide 'rfc2368)
 140
 141 ;;; arch-tag: ea804934-ad96-4f69-957b-857a76e4fd95
 142 ;;; rfc2368.el ends here