1 ;;; cookie1.el --- retrieve random phrases from fortune cookie files
3 ;; Copyright (C) 1993, 2001, 2002, 2003, 2004, 2005,
4 ;; 2006, 2007, 2008 Free Software Foundation, Inc.
6 ;; Author: Eric S. Raymond <esr@snark.thyrsus.com>
8 ;; Keywords: games, extensions
9 ;; Created: Mon Mar 22 17:06:26 1993
11 ;; This file is part of GNU Emacs.
13 ;; GNU Emacs is free software; you can redistribute it and/or modify
14 ;; it under the terms of the GNU General Public License as published by
15 ;; the Free Software Foundation; either version 3, or (at your option)
18 ;; GNU Emacs is distributed in the hope that it will be useful,
19 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
20 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 ;; GNU General Public License for more details.
23 ;; You should have received a copy of the GNU General Public License
24 ;; along with GNU Emacs; see the file COPYING. If not, write to the
25 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
26 ;; Boston, MA 02110-1301, USA.
30 ;; Support for random cookie fetches from phrase files, used for such
31 ;; critical applications as emulating Zippy the Pinhead and confounding
32 ;; the NSA Trunk Trawler.
34 ;; The two entry points are `cookie' and `cookie-insert'. The helper
35 ;; function `shuffle-vector' may be of interest to programmers.
37 ;; The code expects phrase files to be in one of two formats:
39 ;; * ITS-style LINS format (strings terminated by ASCII 0 characters,
40 ;; leading whitespace ignored).
42 ;; * UNIX fortune file format (quotes terminated by %% on a line by itself).
44 ;; Everything up to the first delimiter is treated as a comment. Other
45 ;; formats could be supported by adding alternates to the regexp
46 ;; `cookie-delimiter'.
48 ;; strfile(1) is the program used to compile the files for fortune(6).
49 ;; In order to achieve total compatibility with strfile(1), cookie files
50 ;; should start with two consecutive delimiters (and no comment).
52 ;; This code derives from Steve Strassman's 1987 spook.el package, but
53 ;; has been generalized so that it supports multiple simultaneous
54 ;; cookie databases and fortune files. It is intended to be called
55 ;; from other packages such as yow.el and spook.el.
57 ;; TO DO: teach cookie-snarf to auto-detect ITS PINS or UNIX fortune(6)
58 ;; format and do the right thing.
62 ; Randomize the seed in the random number generator.
65 (defconst cookie-delimiter
"\n%%\n\\|\n%\n\\|\0"
66 "Delimiter used to separate cookie file entries.")
68 (defvar cookie-cache
(make-vector 511 0)
69 "Cache of cookie files that have already been snarfed.")
72 (defun cookie (phrase-file startmsg endmsg
)
73 "Return a random phrase from PHRASE-FILE.
74 When the phrase file is read in, display STARTMSG at the beginning
75 of load, ENDMSG at the end."
76 (let ((cookie-vector (cookie-snarf phrase-file startmsg endmsg
)))
77 (shuffle-vector cookie-vector
)
78 (aref cookie-vector
0)))
81 (defun cookie-insert (phrase-file &optional count startmsg endmsg
)
82 "Insert random phrases from PHRASE-FILE; COUNT of them.
83 When the phrase file is read in, display STARTMSG at the beginning
84 of load, ENDMSG at the end."
85 (let ((cookie-vector (cookie-snarf phrase-file startmsg endmsg
)))
86 (shuffle-vector cookie-vector
)
87 (let ((start (point)))
89 (cookie1 (min (- (length cookie-vector
) 1) (or count
1)) cookie-vector
)
91 (fill-region-as-paragraph start
(point) nil
))))
93 (defun cookie1 (arg cookie-vec
)
94 "Inserts a cookie phrase ARG times."
96 (t (insert (aref cookie-vec arg
))
98 (cookie1 (1- arg
) cookie-vec
))))
101 (defun cookie-snarf (phrase-file startmsg endmsg
)
102 "Reads in the PHRASE-FILE, returns it as a vector of strings.
103 Emit STARTMSG and ENDMSG before and after. Caches the result; second
104 and subsequent calls on the same file won't go to disk."
105 (let ((sym (intern-soft phrase-file cookie-cache
)))
106 (and sym
(not (equal (symbol-function sym
)
107 (nth 5 (file-attributes phrase-file
))))
108 (yes-or-no-p (concat phrase-file
109 " has changed. Read new contents? "))
113 (setq sym
(intern phrase-file cookie-cache
))
114 (message "%s" startmsg
)
116 (let ((buf (generate-new-buffer "*cookie*"))
119 (fset sym
(nth 5 (file-attributes phrase-file
)))
120 (insert-file-contents (expand-file-name phrase-file
))
121 (re-search-forward cookie-delimiter
)
122 (while (progn (skip-chars-forward " \t\n\r\f") (not (eobp)))
124 (re-search-forward cookie-delimiter
)
125 (setq result
(cons (buffer-substring beg
(match-beginning 0))
128 (message "%s" endmsg
)
129 (set sym
(apply 'vector result
)))))))
131 (defun read-cookie (prompt phrase-file startmsg endmsg
&optional require-match
)
132 "Prompt with PROMPT and read with completion among cookies in PHRASE-FILE.
133 STARTMSG and ENDMSG are passed along to `cookie-snarf'.
134 Optional fifth arg REQUIRE-MATCH non-nil forces a matching cookie."
135 ;; Make sure the cookies are in the cache.
136 (or (intern-soft phrase-file cookie-cache
)
137 (cookie-snarf phrase-file startmsg endmsg
))
138 (completing-read prompt
139 (let ((sym (intern phrase-file cookie-cache
)))
140 ;; We cache the alist form of the cookie in a property.
141 (or (get sym
'completion-alist
)
143 (vec (cookie-snarf phrase-file
146 (while (> (setq i
(1- i
)) 0)
147 (setq alist
(cons (list (aref vec i
)) alist
)))
148 (put sym
'completion-alist alist
))))
149 nil require-match nil nil
))
151 ; Thanks to Ian G Batten <BattenIG@CS.BHAM.AC.UK>
152 ; [of the University of Birmingham Computer Science Department]
153 ; for the iterative version of this shuffle.
156 (defun shuffle-vector (vector)
157 "Randomly permute the elements of VECTOR (all permutations equally likely)."
161 (len (length vector
)))
163 (setq j
(+ i
(random (- len i
))))
164 (setq temp
(aref vector i
))
165 (aset vector i
(aref vector j
))
172 ;;; arch-tag: 4a8a8712-df6a-4f34-b030-108a1b47f9f2
173 ;;; cookie1.el ends here