lisp/mail/uudecode.el

   1 ;;; uudecode.el -- elisp native uudecode
   2
   3 ;; Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004,
   4 ;;   2005, 2006, 2007 Free Software Foundation, Inc.
   5
   6 ;; Author: Shenghuo Zhu <zsh@cs.rochester.edu>
   7 ;; Keywords: uudecode news
   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, 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 ;;; Code:
  29
  30 (eval-when-compile (require 'cl))
  31
  32 (eval-and-compile
  33   (defalias 'uudecode-char-int
  34     (if (fboundp 'char-int)
  35         'char-int
  36       'identity)))
  37
  38 (defgroup uudecode nil
  39   "Decoding of uuencoded data."
  40   :group 'mail
  41   :group 'news)
  42
  43 (defcustom uudecode-decoder-program "uudecode"
  44   "*Non-nil value should be a string that names a uu decoder.
  45 The program should expect to read uu data on its standard
  46 input and write the converted data to its standard output."
  47   :type 'string
  48   :group 'uudecode)
  49
  50 (defcustom uudecode-decoder-switches nil
  51   "*List of command line flags passed to `uudecode-decoder-program'."
  52   :group 'uudecode
  53   :type '(repeat string))
  54
  55 (defcustom uudecode-use-external
  56   (executable-find uudecode-decoder-program)
  57   "*Use external uudecode program."
  58   :version "22.1"
  59   :group 'uudecode
  60   :type 'boolean)
  61
  62 (defconst uudecode-alphabet "\040-\140")
  63
  64 (defconst uudecode-begin-line "^begin[ \t]+[0-7][0-7][0-7][ \t]+\\(.*\\)$")
  65 (defconst uudecode-end-line "^end[ \t]*$")
  66
  67 (defconst uudecode-body-line
  68   (let ((i 61) (str "^M"))
  69     (while (> (setq i (1- i)) 0)
  70       (setq str (concat str "[^a-z]")))
  71     (concat str ".?$")))
  72
  73 (defvar uudecode-temporary-file-directory
  74   (cond ((fboundp 'temp-directory) (temp-directory))
  75         ((boundp 'temporary-file-directory) temporary-file-directory)
  76         ("/tmp")))
  77
  78 ;;;###autoload
  79 (defun uudecode-decode-region-external (start end &optional file-name)
  80   "Uudecode region between START and END using external program.
  81 If FILE-NAME is non-nil, save the result to FILE-NAME.  The program
  82 used is specified by `uudecode-decoder-program'."
  83   (interactive "r\nP")
  84   (let ((cbuf (current-buffer)) tempfile firstline status)
  85     (save-excursion
  86       (goto-char start)
  87       (when (re-search-forward uudecode-begin-line nil t)
  88         (forward-line 1)
  89         (setq firstline (point))
  90         (cond ((null file-name))
  91               ((stringp file-name))
  92               (t
  93                (setq file-name (read-file-name "File to Name:"
  94                                                nil nil nil
  95                                                (match-string 1)))))
  96         (setq tempfile (if file-name
  97                            (expand-file-name file-name)
  98                            (if (fboundp 'make-temp-file)
  99                                (let ((temporary-file-directory
 100                                       uudecode-temporary-file-directory))
 101                                  (make-temp-file "uu"))
 102                              (expand-file-name
 103                               (make-temp-name "uu")
 104                               uudecode-temporary-file-directory))))
 105         (let ((cdir default-directory)
 106               (default-process-coding-system
 107                 (if (featurep 'xemacs)
 108                     ;; In XEmacs, `nil' is not a valid coding system.
 109                     '(binary . binary)
 110                   nil)))
 111           (unwind-protect
 112               (with-temp-buffer
 113                 (insert "begin 600 " (file-name-nondirectory tempfile) "\n")
 114                 (insert-buffer-substring cbuf firstline end)
 115                 (cd (file-name-directory tempfile))
 116                 (apply 'call-process-region
 117                        (point-min)
 118                        (point-max)
 119                        uudecode-decoder-program
 120                        nil
 121                        nil
 122                        nil
 123                        uudecode-decoder-switches))
 124             (cd cdir) (set-buffer cbuf)))
 125         (if (file-exists-p tempfile)
 126             (unless file-name
 127               (goto-char start)
 128               (delete-region start end)
 129               (let (format-alist)
 130                 (insert-file-contents-literally tempfile)))
 131           (message "Can not uudecode")))
 132       (ignore-errors (or file-name (delete-file tempfile))))))
 133
 134 (eval-and-compile
 135   (defalias 'uudecode-string-to-multibyte
 136     (cond
 137      ((featurep 'xemacs)
 138       'identity)
 139      ((fboundp 'string-to-multibyte)
 140       'string-to-multibyte)
 141      (t
 142       (lambda (string)
 143         "Return a multibyte string with the same individual chars as string."
 144         (mapconcat
 145          (lambda (ch) (string-as-multibyte (char-to-string ch)))
 146          string ""))))))
 147
 148 ;;;###autoload
 149 (defun uudecode-decode-region-internal (start end &optional file-name)
 150   "Uudecode region between START and END without using an external program.
 151 If FILE-NAME is non-nil, save the result to FILE-NAME."
 152   (interactive "r\nP")
 153   (let ((done nil)
 154         (counter 0)
 155         (remain 0)
 156         (bits 0)
 157         (lim 0) inputpos result
 158         (non-data-chars (concat "^" uudecode-alphabet)))
 159     (save-excursion
 160       (goto-char start)
 161       (when (re-search-forward uudecode-begin-line nil t)
 162         (cond ((null file-name))
 163               ((stringp file-name))
 164               (t
 165                (setq file-name (expand-file-name
 166                                 (read-file-name "File to Name:"
 167                                                 nil nil nil
 168                                                 (match-string 1))))))
 169         (forward-line 1)
 170         (skip-chars-forward non-data-chars end)
 171         (while (not done)
 172           (setq inputpos (point))
 173           (setq remain 0 bits 0 counter 0)
 174           (cond
 175            ((> (skip-chars-forward uudecode-alphabet end) 0)
 176             (setq lim (point))
 177             (setq remain
 178                   (logand (- (uudecode-char-int (char-after inputpos)) 32)
 179                           63))
 180             (setq inputpos (1+ inputpos))
 181             (if (= remain 0) (setq done t))
 182             (while (and (< inputpos lim) (> remain 0))
 183               (setq bits (+ bits
 184                             (logand
 185                              (-
 186                               (uudecode-char-int (char-after inputpos)) 32)
 187                              63)))
 188               (if (/= counter 0) (setq remain (1- remain)))
 189               (setq counter (1+ counter)
 190                     inputpos (1+ inputpos))
 191               (cond ((= counter 4)
 192                      (setq result (cons
 193                                    (concat
 194                                     (char-to-string (lsh bits -16))
 195                                     (char-to-string (logand (lsh bits -8) 255))
 196                                     (char-to-string (logand bits 255)))
 197                                    result))
 198                      (setq bits 0 counter 0))
 199                     (t (setq bits (lsh bits 6)))))))
 200           (cond
 201            (done)
 202            ((> 0 remain)
 203             (error "uucode line ends unexpectly")
 204             (setq done t))
 205            ((and (= (point) end) (not done))
 206             ;;(error "uucode ends unexpectly")
 207             (setq done t))
 208            ((= counter 3)
 209             (setq result (cons
 210                           (concat
 211                            (char-to-string (logand (lsh bits -16) 255))
 212                            (char-to-string (logand (lsh bits -8) 255)))
 213                           result)))
 214            ((= counter 2)
 215             (setq result (cons
 216                           (char-to-string (logand (lsh bits -10) 255))
 217                           result))))
 218           (skip-chars-forward non-data-chars end))
 219         (if file-name
 220             (let (default-enable-multibyte-characters)
 221               (with-temp-file file-name
 222                 (insert (apply 'concat (nreverse result)))))
 223           (or (markerp end) (setq end (set-marker (make-marker) end)))
 224           (goto-char start)
 225           (if enable-multibyte-characters
 226               (mapc #'(lambda (x) (insert (uudecode-string-to-multibyte x)))
 227                     (nreverse result))
 228             (insert (apply 'concat (nreverse result))))
 229           (delete-region (point) end))))))
 230
 231 ;;;###autoload
 232 (defun uudecode-decode-region (start end &optional file-name)
 233   "Uudecode region between START and END.
 234 If FILE-NAME is non-nil, save the result to FILE-NAME."
 235   (if uudecode-use-external
 236       (uudecode-decode-region-external start end file-name)
 237     (uudecode-decode-region-internal start end file-name)))
 238
 239 (provide 'uudecode)
 240
 241 ;;; arch-tag: e1f09ed5-62b4-4677-9f13-4e81c4fe8ce3
 242 ;;; uudecode.el ends here