|
155
|
1 ;;; mule-caesar.el --- ROT 13-47 Caesar rotation utility
|
|
|
2
|
|
|
3 ;; Copyright (C) 1997 Free Software Foundation, Inc.
|
|
|
4
|
|
|
5 ;; Author: MORIOKA Tomohiko <morioka@jaist.ac.jp>
|
|
|
6 ;; Version: $Id: mule-caesar.el,v 1.1 1997/06/03 04:18:36 steve Exp $
|
|
|
7 ;; Keywords: ROT 13-47, caesar, mail, news, text/x-rot13-47
|
|
|
8
|
|
|
9 ;; This file is part of APEL (A Portable Emacs Library).
|
|
|
10
|
|
|
11 ;; This program is free software; you can redistribute it and/or
|
|
|
12 ;; modify it under the terms of the GNU General Public License as
|
|
|
13 ;; published by the Free Software Foundation; either version 2, or (at
|
|
|
14 ;; your option) any later version.
|
|
|
15
|
|
|
16 ;; This program is distributed in the hope that it will be useful, but
|
|
|
17 ;; WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
|
18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
|
19 ;; 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., 59 Temple Place - Suite 330,
|
|
|
24 ;; Boston, MA 02111-1307, USA.
|
|
|
25
|
|
|
26 ;;; Code:
|
|
|
27
|
|
|
28 (defun char-to-octet-list (character)
|
|
|
29 "Return list of octets in code table of graphic character set."
|
|
|
30 (let* ((code (char-int character))
|
|
|
31 (dim (charset-dimension (char-charset code)))
|
|
|
32 dest)
|
|
|
33 (while (> dim 0)
|
|
|
34 (setq dest (cons (logand code 127) dest)
|
|
|
35 dim (1- dim)
|
|
|
36 code (lsh code -7))
|
|
|
37 )
|
|
|
38 dest))
|
|
|
39
|
|
|
40 (defun mule-caesar-region (start end &optional stride-ascii)
|
|
|
41 "Caesar rotation of current region.
|
|
|
42 Optional argument STRIDE-ASCII is rotation-size for Latin alphabet
|
|
|
43 \(A-Z and a-z). For non-ASCII text, ROT-N/2 will be performed in any
|
|
|
44 case (N=charset-chars; 94 for 94 or 94x94 graphic character set; 96
|
|
|
45 for 96 or 96x96 graphic character set)."
|
|
|
46 (interactive "r\nP")
|
|
|
47 (setq stride-ascii (if stride-ascii
|
|
|
48 (mod stride-ascii 26)
|
|
|
49 13))
|
|
|
50 (save-excursion
|
|
|
51 (save-restriction
|
|
|
52 (narrow-to-region start end)
|
|
|
53 (goto-char start)
|
|
|
54 (while (< (point)(point-max))
|
|
|
55 (let* ((chr (char-after (point)))
|
|
|
56 (charset (char-charset chr))
|
|
|
57 )
|
|
|
58 (if (eq charset 'ascii)
|
|
|
59 (cond ((and (<= ?A chr) (<= chr ?Z))
|
|
|
60 (setq chr (+ chr stride-ascii))
|
|
|
61 (if (> chr ?Z)
|
|
|
62 (setq chr (- chr 26))
|
|
|
63 )
|
|
|
64 (delete-char 1)
|
|
|
65 (insert chr)
|
|
|
66 )
|
|
|
67 ((and (<= ?a chr) (<= chr ?z))
|
|
|
68 (setq chr (+ chr stride-ascii))
|
|
|
69 (if (> chr ?z)
|
|
|
70 (setq chr (- chr 26))
|
|
|
71 )
|
|
|
72 (delete-char 1)
|
|
|
73 (insert chr)
|
|
|
74 )
|
|
|
75 (t
|
|
|
76 (forward-char)
|
|
|
77 ))
|
|
|
78 (let* ((stride (lsh (charset-chars charset) -1))
|
|
|
79 (ret (mapcar (function
|
|
|
80 (lambda (octet)
|
|
|
81 (if (< octet 80)
|
|
|
82 (+ octet stride)
|
|
|
83 (- octet stride)
|
|
|
84 )))
|
|
|
85 (char-to-octet-list chr))))
|
|
|
86 (delete-char 1)
|
|
|
87 (insert (make-char (char-charset chr)
|
|
|
88 (car ret)(car (cdr ret))))
|
|
|
89 )))))))
|
|
|
90
|
|
|
91
|
|
|
92 (provide 'mule-caesar)
|
|
|
93
|
|
|
94 ;;; mule-caesar.el ends here
|
