-;;; decipher.el --- Cryptanalyze monoalphabetic substitution ciphers
+;;; decipher.el --- cryptanalyze monoalphabetic substitution ciphers
;;
-;; Copyright (C) 1995, 1996 Free Software Foundation, Inc.
+;; Copyright (C) 1995, 1996, 2003 Free Software Foundation, Inc.
;;
-;; Author: Christopher J. Madsen <ac608@yfn.ysu.edu>
+;; Author: Christopher J. Madsen <chris_madsen@geocities.com>
;; Keywords: games
;;
;; This file is part of GNU Emacs.
;; GNU General Public License for more details.
;;
;; You should have received a copy of the GNU General Public License
-;; along with GNU Emacs; see the file COPYING. If not, write to
-;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+;; along with GNU Emacs; see the file COPYING. If not, write to the
+;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
+;;; Commentary:
+;;
;;; Quick Start:
;;
;; To decipher a message, type or load it into a buffer and type
;; Helen Fouche Gaines
;; ISBN 0-486-20097-3
-;;; Commentary:
-;;
;; This package is designed to help you crack simple substitution
;; ciphers where one letter stands for another. It works for ciphers
;; with or without word divisions. (You must set the variable
(eval-when-compile
(require 'cl))
-(defvar decipher-force-uppercase t
+(defgroup decipher nil
+ "Cryptanalyze monoalphabetic substitution ciphers."
+ :prefix "decipher-"
+ :group 'games)
+
+(defcustom decipher-force-uppercase t
"*Non-nil means to convert ciphertext to uppercase.
-Nil means the case of the ciphertext is preserved.
-This variable must be set before typing `\\[decipher]'.")
+nil means the case of the ciphertext is preserved.
+This variable must be set before typing `\\[decipher]'."
+ :type 'boolean
+ :group 'decipher)
-(defvar decipher-ignore-spaces nil
+
+(defcustom decipher-ignore-spaces nil
"*Non-nil means to ignore spaces and punctuation when counting digrams.
You should set this to `nil' if the cipher message is divided into words,
or `t' if it is not.
-This variable is buffer-local.")
+This variable is buffer-local."
+ :type 'boolean
+ :group 'decipher)
(make-variable-buffer-local 'decipher-ignore-spaces)
-(defvar decipher-undo-limit 5000
+(defcustom decipher-undo-limit 5000
"The maximum number of entries in the undo list.
When the undo list exceeds this number, 100 entries are deleted from
-the tail of the list.")
+the tail of the list."
+ :type 'integer
+ :group 'decipher)
+
+(defcustom decipher-mode-hook nil
+ "Hook to run upon entry to decipher."
+ :type 'hook
+ :group 'decipher)
;; End of user modifiable variables
;;--------------------------------------------------------------------
(defvar decipher-font-lock-keywords
'(("^:.*" . font-lock-keyword-face)
("^>.*" . font-lock-string-face)
- ("^%!.*" . font-lock-reference-face)
+ ("^%!.*" . font-lock-constant-face)
("^%.*" . font-lock-comment-face)
("\\`(\\([a-z]+\\) +\\([A-Z]+\\)"
(1 font-lock-string-face)
(1 font-lock-keyword-face)
(2 font-lock-string-face)))
"Expressions to fontify in Decipher mode.
-! Ciphertext uses `font-lock-keyword-face', plaintext uses
+
+Ciphertext uses `font-lock-keyword-face', plaintext uses
`font-lock-string-face', comments use `font-lock-comment-face', and
-checkpoints use `font-lock-reference-face'. You can customize the
+checkpoints use `font-lock-constant-face'. You can customize the
display by changing these variables. For best results, I recommend
that all faces use the same background color.
-! For example, to display ciphertext in the `bold' face, use
+
+For example, to display ciphertext in the `bold' face, use
(add-hook 'decipher-mode-hook
(lambda () (set (make-local-variable 'font-lock-keyword-face)
'bold)))
(define-key decipher-mode-map "R" 'decipher-restore-checkpoint)
(define-key decipher-mode-map "U" 'decipher-undo)
(define-key decipher-mode-map " " 'decipher-keypress)
- (substitute-key-definition 'undo 'decipher-undo
- decipher-mode-map global-map)
- (substitute-key-definition 'advertised-undo 'decipher-undo
- decipher-mode-map global-map)
+ (define-key decipher-mode-map [remap undo] 'decipher-undo)
+ (define-key decipher-mode-map [remap advertised-undo] 'decipher-undo)
(let ((key ?a))
(while (<= key ?z)
(define-key decipher-mode-map (vector key) 'decipher-keypress)
(set (make-local-variable 'font-lock-defaults)
'(decipher-font-lock-keywords t))
;; Make the buffer writable when we exit Decipher mode:
- (make-local-hook 'change-major-mode-hook)
(add-hook 'change-major-mode-hook
(lambda () (setq buffer-read-only nil
buffer-undo-list nil))
(setcdr (nthcdr (1- new-size) decipher-undo-list) nil)
(setq decipher-undo-list-size new-size))))))
+(defun decipher-copy-cons (cons)
+ (if cons
+ (cons (car cons) (cdr cons))))
+
(defun decipher-get-undo (cipher-char plain-char)
;; Return an undo record that will undo the result of
;; (decipher-set-map CIPHER-CHAR PLAIN-CHAR)
- ;; We must use copy-list because the original cons cells will be
+ ;; We must copy the cons cell because the original cons cells will be
;; modified using setcdr.
- (let ((cipher-map (copy-list (rassoc cipher-char decipher-alphabet)))
- (plain-map (copy-list (assoc plain-char decipher-alphabet))))
+ (let ((cipher-map (decipher-copy-cons (rassoc cipher-char decipher-alphabet)))
+ (plain-map (decipher-copy-cons (assoc plain-char decipher-alphabet))))
(cond ((equal ?\ plain-char)
cipher-map)
((equal cipher-char (cdr plain-map))
(set-buffer (decipher-stats-buffer))
(goto-char (point-min))
(or (re-search-forward (format "^%c: " cipher-char) nil t)
- (error "Character `%c' is not used in ciphertext." cipher-char))
+ (error "Character `%c' is not used in ciphertext" cipher-char))
(forward-line -1)
(setq start (point))
(forward-line 3)