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1 ;;; mule.el --- basic commands for mulitilingual environment
2
3 ;; Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
4 ;; Free Software Foundation, Inc.
5 ;; Copyright (C) 1995, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
6 ;; National Institute of Advanced Industrial Science and Technology (AIST)
7 ;; Registration Number H14PRO021
8
9 ;; Keywords: mule, multilingual, character set, coding system
10
11 ;; This file is part of GNU Emacs.
12
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 2, or (at your option)
16 ;; any later version.
17
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.
22
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.
27
28 ;;; Commentary:
29
30 ;;; Code:
31
32 (defconst mule-version "5.0 (SAKAKI)" "\
33 Version number and name of this version of MULE (multilingual environment).")
34
35 (defconst mule-version-date "1999.12.7" "\
36 Distribution date of this version of MULE (multilingual environment).")
37
38 (defun load-with-code-conversion (fullname file &optional noerror nomessage)
39 "Execute a file of Lisp code named FILE whose absolute name is FULLNAME.
40 The file contents are decoded before evaluation if necessary.
41 If optional second arg NOERROR is non-nil,
42 report no error if FILE doesn't exist.
43 Print messages at start and end of loading unless
44 optional third arg NOMESSAGE is non-nil.
45 Return t if file exists."
46 (if (null (file-readable-p fullname))
47 (and (null noerror)
48 (signal 'file-error (list "Cannot open load file" file)))
49 ;; Read file with code conversion, and then eval.
50 (let* ((buffer
51 ;; To avoid any autoloading, set default-major-mode to
52 ;; fundamental-mode.
53 ;; So that we don't get completely screwed if the
54 ;; file is encoded in some complicated character set,
55 ;; read it with real decoding, as a multibyte buffer,
56 ;; even if this is a --unibyte Emacs session.
57 (let ((default-major-mode 'fundamental-mode)
58 (default-enable-multibyte-characters t))
59 ;; We can't use `generate-new-buffer' because files.el
60 ;; is not yet loaded.
61 (get-buffer-create (generate-new-buffer-name " *load*"))))
62 (load-in-progress t)
63 (source (save-match-data (string-match "\\.el\\'" fullname))))
64 (unless nomessage
65 (if source
66 (message "Loading %s (source)..." file)
67 (message "Loading %s..." file)))
68 (when purify-flag
69 (push file preloaded-file-list))
70 (unwind-protect
71 (let ((load-file-name fullname)
72 (set-auto-coding-for-load t)
73 (inhibit-file-name-operation nil))
74 (save-excursion
75 (set-buffer buffer)
76 ;; Don't let deactivate-mark remain set.
77 (let (deactivate-mark)
78 (insert-file-contents fullname))
79 ;; If the loaded file was inserted with no-conversion or
80 ;; raw-text coding system, make the buffer unibyte.
81 ;; Otherwise, eval-buffer might try to interpret random
82 ;; binary junk as multibyte characters.
83 (if (and enable-multibyte-characters
84 (or (eq (coding-system-type last-coding-system-used) 5)
85 (eq last-coding-system-used 'no-conversion)))
86 (set-buffer-multibyte nil))
87 ;; Make `kill-buffer' quiet.
88 (set-buffer-modified-p nil))
89 ;; Have the original buffer current while we eval.
90 (eval-buffer buffer nil
91 ;; This is compatible with what `load' does.
92 (if purify-flag file fullname)
93 ;; If this Emacs is running with --unibyte,
94 ;; convert multibyte strings to unibyte
95 ;; after reading them.
96 ;; (not default-enable-multibyte-characters)
97 nil t
98 ))
99 (let (kill-buffer-hook kill-buffer-query-functions)
100 (kill-buffer buffer)))
101 (let ((hook (assoc file after-load-alist)))
102 (when hook
103 (mapcar (function eval) (cdr hook))))
104 (unless (or nomessage noninteractive)
105 (if source
106 (message "Loading %s (source)...done" file)
107 (message "Loading %s...done" file)))
108 t)))
109
110 ;; API (Application Program Interface) for charsets.
111
112 (defsubst charset-quoted-standard-p (obj)
113 "Return t if OBJ is a quoted symbol, and is the name of a standard charset."
114 (and (listp obj) (eq (car obj) 'quote)
115 (symbolp (car-safe (cdr obj)))
116 (let ((vector (get (car-safe (cdr obj)) 'charset)))
117 (and (vectorp vector)
118 (< (aref vector 0) 160)))))
119
120 (defsubst charsetp (object)
121 "T if OBJECT is a charset."
122 (and (symbolp object) (vectorp (get object 'charset))))
123
124 (defsubst charset-info (charset)
125 "Return a vector of information of CHARSET.
126 The elements of the vector are:
127 CHARSET-ID, BYTES, DIMENSION, CHARS, WIDTH, DIRECTION,
128 LEADING-CODE-BASE, LEADING-CODE-EXT,
129 ISO-FINAL-CHAR, ISO-GRAPHIC-PLANE,
130 REVERSE-CHARSET, SHORT-NAME, LONG-NAME, DESCRIPTION,
131 PLIST,
132 where
133 CHARSET-ID (integer) is the identification number of the charset.
134 BYTES (integer) is the length of multi-byte form of a character in
135 the charset: one of 1, 2, 3, and 4.
136 DIMENSION (integer) is the number of bytes to represent a character of
137 the charset: 1 or 2.
138 CHARS (integer) is the number of characters in a dimension: 94 or 96.
139 WIDTH (integer) is the number of columns a character in the charset
140 occupies on the screen: one of 0, 1, and 2.
141 DIRECTION (integer) is the rendering direction of characters in the
142 charset when rendering. If 0, render from left to right, else
143 render from right to left.
144 LEADING-CODE-BASE (integer) is the base leading-code for the
145 charset.
146 LEADING-CODE-EXT (integer) is the extended leading-code for the
147 charset. All charsets of less than 0xA0 has the value 0.
148 ISO-FINAL-CHAR (character) is the final character of the
149 corresponding ISO 2022 charset. If the charset is not assigned
150 any final character, the value is -1.
151 ISO-GRAPHIC-PLANE (integer) is the graphic plane to be invoked
152 while encoding to variants of ISO 2022 coding system, one of the
153 following: 0/graphic-plane-left(GL), 1/graphic-plane-right(GR).
154 If the charset is not assigned any final character, the value is -1.
155 REVERSE-CHARSET (integer) is the charset which differs only in
156 LEFT-TO-RIGHT value from the charset. If there's no such a
157 charset, the value is -1.
158 SHORT-NAME (string) is the short name to refer to the charset.
159 LONG-NAME (string) is the long name to refer to the charset
160 DESCRIPTION (string) is the description string of the charset.
161 PLIST (property list) may contain any type of information a user
162 want to put and get by functions `put-charset-property' and
163 `get-charset-property' respectively."
164 (get charset 'charset))
165
166 ;; It is better not to use backquote in this file,
167 ;; because that makes a bootstrapping problem
168 ;; if you need to recompile all the Lisp files using interpreted code.
169
170 (defmacro charset-id (charset)
171 "Return charset identification number of CHARSET."
172 (if (charset-quoted-standard-p charset)
173 (aref (charset-info (nth 1 charset)) 0)
174 (list 'aref (list 'charset-info charset) 0)))
175
176 (defmacro charset-bytes (charset)
177 "Return bytes of CHARSET.
178 See the function `charset-info' for more detail."
179 (if (charset-quoted-standard-p charset)
180 (aref (charset-info (nth 1 charset)) 1)
181 (list 'aref (list 'charset-info charset) 1)))
182
183 (defmacro charset-dimension (charset)
184 "Return dimension of CHARSET.
185 See the function `charset-info' for more detail."
186 (if (charset-quoted-standard-p charset)
187 (aref (charset-info (nth 1 charset)) 2)
188 (list 'aref (list 'charset-info charset) 2)))
189
190 (defmacro charset-chars (charset)
191 "Return character numbers contained in a dimension of CHARSET.
192 See the function `charset-info' for more detail."
193 (if (charset-quoted-standard-p charset)
194 (aref (charset-info (nth 1 charset)) 3)
195 (list 'aref (list 'charset-info charset) 3)))
196
197 (defmacro charset-width (charset)
198 "Return width (how many column occupied on a screen) of CHARSET.
199 See the function `charset-info' for more detail."
200 (if (charset-quoted-standard-p charset)
201 (aref (charset-info (nth 1 charset)) 4)
202 (list 'aref (list 'charset-info charset) 4)))
203
204 (defmacro charset-direction (charset)
205 "Return direction of CHARSET.
206 See the function `charset-info' for more detail."
207 (if (charset-quoted-standard-p charset)
208 (aref (charset-info (nth 1 charset)) 5)
209 (list 'aref (list 'charset-info charset) 5)))
210
211 (defmacro charset-iso-final-char (charset)
212 "Return final char of CHARSET.
213 See the function `charset-info' for more detail."
214 (if (charset-quoted-standard-p charset)
215 (aref (charset-info (nth 1 charset)) 8)
216 (list 'aref (list 'charset-info charset) 8)))
217
218 (defmacro charset-iso-graphic-plane (charset)
219 "Return graphic plane of CHARSET.
220 See the function `charset-info' for more detail."
221 (if (charset-quoted-standard-p charset)
222 (aref (charset-info (nth 1 charset)) 9)
223 (list 'aref (list 'charset-info charset) 9)))
224
225 (defmacro charset-reverse-charset (charset)
226 "Return reverse charset of CHARSET.
227 See the function `charset-info' for more detail."
228 (if (charset-quoted-standard-p charset)
229 (aref (charset-info (nth 1 charset)) 10)
230 (list 'aref (list 'charset-info charset) 10)))
231
232 (defmacro charset-short-name (charset)
233 "Return short name of CHARSET.
234 See the function `charset-info' for more detail."
235 (if (charset-quoted-standard-p charset)
236 (aref (charset-info (nth 1 charset)) 11)
237 (list 'aref (list 'charset-info charset) 11)))
238
239 (defmacro charset-long-name (charset)
240 "Return long name of CHARSET.
241 See the function `charset-info' for more detail."
242 (if (charset-quoted-standard-p charset)
243 (aref (charset-info (nth 1 charset)) 12)
244 (list 'aref (list 'charset-info charset) 12)))
245
246 (defmacro charset-description (charset)
247 "Return description of CHARSET.
248 See the function `charset-info' for more detail."
249 (if (charset-quoted-standard-p charset)
250 (aref (charset-info (nth 1 charset)) 13)
251 (list 'aref (list 'charset-info charset) 13)))
252
253 (defmacro charset-plist (charset)
254 "Return list charset property of CHARSET.
255 See the function `charset-info' for more detail."
256 (list 'aref
257 (if (charset-quoted-standard-p charset)
258 (charset-info (nth 1 charset))
259 (list 'charset-info charset))
260 14))
261
262 (defun set-charset-plist (charset plist)
263 "Set CHARSET's property list to PLIST, and return PLIST."
264 (aset (charset-info charset) 14 plist))
265
266 (defun make-char (charset &optional code1 code2)
267 "Return a character of CHARSET whose position codes are CODE1 and CODE2.
268 CODE1 and CODE2 are optional, but if you don't supply
269 sufficient position codes, return a generic character which stands for
270 all characters or group of characters in the character set.
271 A generic character can be used to index a char table (e.g. syntax-table).
272
273 Such character sets as ascii, eight-bit-control, and eight-bit-graphic
274 don't have corresponding generic characters. If CHARSET is one of
275 them and you don't supply CODE1, return the character of the smallest
276 code in CHARSET.
277
278 If CODE1 or CODE2 are invalid (out of range), this function signals an
279 error. However, the eighth bit of both CODE1 and CODE2 is zeroed
280 before they are used to index CHARSET. Thus you may use, say, the
281 actual ISO 8859 character code rather than subtracting 128, as you
282 would need to index the corresponding Emacs charset."
283 (make-char-internal (charset-id charset) code1 code2))
284
285 (put 'make-char 'byte-compile
286 (function
287 (lambda (form)
288 (let ((charset (nth 1 form)))
289 (if (charset-quoted-standard-p charset)
290 (byte-compile-normal-call
291 (cons 'make-char-internal
292 (cons (charset-id (nth 1 charset)) (nthcdr 2 form))))
293 (byte-compile-normal-call
294 (cons 'make-char-internal
295 (cons (list 'charset-id charset) (nthcdr 2 form)))))))))
296
297 (defun charset-list ()
298 "Return list of charsets ever defined.
299
300 This function is provided for backward compatibility.
301 Now we have the variable `charset-list'."
302 charset-list)
303
304 (defsubst generic-char-p (char)
305 "Return t if and only if CHAR is a generic character.
306 See also the documentation of `make-char'."
307 (and (>= char 0400)
308 (let ((l (split-char char)))
309 (and (or (= (nth 1 l) 0) (eq (nth 2 l) 0))
310 (not (eq (car l) 'composition))))))
311
312 (defun decode-char (ccs code-point &optional restriction)
313 "Return character specified by coded character set CCS and CODE-POINT in it.
314 Return nil if such a character is not supported.
315 Currently the only supported coded character set is `ucs' (ISO/IEC
316 10646: Universal Multi-Octet Coded Character Set), and the result is
317 translated through the translation-table named
318 `utf-translation-table-for-decode' or the translation-hash-table named
319 `utf-subst-table-for-decode'.
320
321 Optional argument RESTRICTION specifies a way to map the pair of CCS
322 and CODE-POINT to a character. Currently not supported and just ignored."
323 (cond
324 ((eq ccs 'ucs)
325 (or (utf-lookup-subst-table-for-decode code-point)
326 (let ((c (cond
327 ((< code-point 160)
328 code-point)
329 ((< code-point 256)
330 (make-char 'latin-iso8859-1 code-point))
331 ((< code-point #x2500)
332 (setq code-point (- code-point #x0100))
333 (make-char 'mule-unicode-0100-24ff
334 (+ (/ code-point 96) 32) (+ (% code-point 96) 32)))
335 ((< code-point #x3400)
336 (setq code-point (- code-point #x2500))
337 (make-char 'mule-unicode-2500-33ff
338 (+ (/ code-point 96) 32) (+ (% code-point 96) 32)))
339 ((and (>= code-point #xe000) (< code-point #x10000))
340 (setq code-point (- code-point #xe000))
341 (make-char 'mule-unicode-e000-ffff
342 (+ (/ code-point 96) 32)
343 (+ (% code-point 96) 32))))))
344 (when c
345 (or (aref (get 'utf-translation-table-for-decode
346 'translation-table) c)
347 c)))))))
348
349 (defun encode-char (char ccs &optional restriction)
350 "Return code-point in coded character set CCS that corresponds to CHAR.
351 Return nil if CHAR is not included in CCS.
352 Currently the only supported coded character set is `ucs' (ISO/IEC
353 10646: Universal Multi-Octet Coded Character Set), and CHAR is first
354 translated through the translation-table named
355 `utf-translation-table-for-encode' or the translation-hash-table named
356 `utf-subst-table-for-encode'.
357
358 CHAR should be in one of these charsets:
359 ascii, latin-iso8859-1, mule-unicode-0100-24ff, mule-unicode-2500-33ff,
360 mule-unicode-e000-ffff, eight-bit-control
361 Otherwise, return nil.
362
363 Optional argument RESTRICTION specifies a way to map CHAR to a
364 code-point in CCS. Currently not supported and just ignored."
365 (let* ((split (split-char char))
366 (charset (car split))
367 trans)
368 (cond ((eq ccs 'ucs)
369 (or (utf-lookup-subst-table-for-encode char)
370 (let ((table (get 'utf-translation-table-for-encode
371 'translation-table)))
372 (setq trans (aref table char))
373 (if trans
374 (setq split (split-char trans)
375 charset (car split)))
376 (cond ((eq charset 'ascii)
377 (or trans char))
378 ((eq charset 'latin-iso8859-1)
379 (+ (nth 1 split) 128))
380 ((eq charset 'mule-unicode-0100-24ff)
381 (+ #x0100 (+ (* (- (nth 1 split) 32) 96)
382 (- (nth 2 split) 32))))
383 ((eq charset 'mule-unicode-2500-33ff)
384 (+ #x2500 (+ (* (- (nth 1 split) 32) 96)
385 (- (nth 2 split) 32))))
386 ((eq charset 'mule-unicode-e000-ffff)
387 (+ #xe000 (+ (* (- (nth 1 split) 32) 96)
388 (- (nth 2 split) 32))))
389 ((eq charset 'eight-bit-control)
390 char))))))))
391
392 \f
393 ;; Coding system stuff
394
395 ;; Coding system is a symbol that has the property `coding-system'.
396 ;;
397 ;; The value of the property `coding-system' is a vector of the
398 ;; following format:
399 ;; [TYPE MNEMONIC DOC-STRING PLIST FLAGS]
400 ;; We call this vector as coding-spec. See comments in src/coding.c
401 ;; for more detail.
402
403 (defconst coding-spec-type-idx 0)
404 (defconst coding-spec-mnemonic-idx 1)
405 (defconst coding-spec-doc-string-idx 2)
406 (defconst coding-spec-plist-idx 3)
407 (defconst coding-spec-flags-idx 4)
408
409 ;; PLIST is a property list of a coding system. To share PLIST among
410 ;; alias coding systems, a coding system has PLIST in coding-spec
411 ;; instead of having it in normal property list of Lisp symbol.
412 ;; Here's a list of coding system properties currently being used.
413 ;;
414 ;; o coding-category
415 ;;
416 ;; The value is a coding category the coding system belongs to. The
417 ;; function `make-coding-system' sets this value automatically
418 ;; unless its argument PROPERTIES specifies this property.
419 ;;
420 ;; o alias-coding-systems
421 ;;
422 ;; The value is a list of coding systems of the same alias group. The
423 ;; first element is the coding system made at first, which we call as
424 ;; `base coding system'. The function `make-coding-system' sets this
425 ;; value automatically and `define-coding-system-alias' updates it.
426 ;;
427 ;; See the documentation of make-coding-system for the meanings of the
428 ;; following properties.
429 ;;
430 ;; o post-read-conversion
431 ;; o pre-write-conversion
432 ;; o translation-table-for-decode
433 ;; o translation-table-for-encode
434 ;; o safe-chars
435 ;; o safe-charsets
436 ;; o mime-charset
437 ;; o valid-codes (meaningful only for a coding system based on CCL)
438
439
440 (defsubst coding-system-spec (coding-system)
441 "Return coding-spec of CODING-SYSTEM."
442 (get (check-coding-system coding-system) 'coding-system))
443
444 (defun coding-system-type (coding-system)
445 "Return the coding type of CODING-SYSTEM.
446 A coding type is an integer value indicating the encoding method
447 of CODING-SYSTEM. See the function `make-coding-system' for more detail."
448 (aref (coding-system-spec coding-system) coding-spec-type-idx))
449
450 (defun coding-system-mnemonic (coding-system)
451 "Return the mnemonic character of CODING-SYSTEM.
452 The mnemonic character of a coding system is used in mode line
453 to indicate the coding system. If the arg is nil, return ?-."
454 (let ((spec (coding-system-spec coding-system)))
455 (if spec (aref spec coding-spec-mnemonic-idx) ?-)))
456
457 (defun coding-system-doc-string (coding-system)
458 "Return the documentation string for CODING-SYSTEM."
459 (aref (coding-system-spec coding-system) coding-spec-doc-string-idx))
460
461 (defun coding-system-plist (coding-system)
462 "Return the property list of CODING-SYSTEM."
463 (aref (coding-system-spec coding-system) coding-spec-plist-idx))
464
465 (defun coding-system-flags (coding-system)
466 "Return `flags' of CODING-SYSTEM.
467 A `flags' of a coding system is a vector of length 32 indicating detailed
468 information of a coding system. See the function `make-coding-system'
469 for more detail."
470 (aref (coding-system-spec coding-system) coding-spec-flags-idx))
471
472 (defun coding-system-get (coding-system prop)
473 "Extract a value from CODING-SYSTEM's property list for property PROP."
474 (plist-get (coding-system-plist coding-system) prop))
475
476 (defun coding-system-put (coding-system prop val)
477 "Change value in CODING-SYSTEM's property list PROP to VAL."
478 (let ((plist (coding-system-plist coding-system)))
479 (if plist
480 (plist-put plist prop val)
481 (aset (coding-system-spec coding-system) coding-spec-plist-idx
482 (list prop val)))))
483
484 (defun coding-system-category (coding-system)
485 "Return the coding category of CODING-SYSTEM.
486 See also `coding-category-list'."
487 (coding-system-get coding-system 'coding-category))
488
489 (defun coding-system-base (coding-system)
490 "Return the base coding system of CODING-SYSTEM.
491 A base coding system is what made by `make-coding-system'.
492 Any alias nor subsidiary coding systems are not base coding system."
493 (car (coding-system-get coding-system 'alias-coding-systems)))
494
495 ;; Coding system also has a property `eol-type'.
496 ;;
497 ;; This property indicates how the coding system handles end-of-line
498 ;; format. The value is integer 0, 1, 2, or a vector of three coding
499 ;; systems. Each integer value 0, 1, and 2 indicates the format of
500 ;; end-of-line LF, CRLF, and CR respectively. A vector value
501 ;; indicates that the format of end-of-line should be detected
502 ;; automatically. Nth element of the vector is the subsidiary coding
503 ;; system whose `eol-type' property is N.
504
505 (defun coding-system-eol-type (coding-system)
506 "Return eol-type of CODING-SYSTEM.
507 An eol-type is integer 0, 1, 2, or a vector of coding systems.
508
509 Integer values 0, 1, and 2 indicate a format of end-of-line; LF,
510 CRLF, and CR respectively.
511
512 A vector value indicates that a format of end-of-line should be
513 detected automatically. Nth element of the vector is the subsidiary
514 coding system whose eol-type is N."
515 (get coding-system 'eol-type))
516
517 (defun coding-system-eol-type-mnemonic (coding-system)
518 "Return the string indicating end-of-line format of CODING-SYSTEM."
519 (let* ((eol-type (coding-system-eol-type coding-system))
520 (val (cond ((eq eol-type 0) eol-mnemonic-unix)
521 ((eq eol-type 1) eol-mnemonic-dos)
522 ((eq eol-type 2) eol-mnemonic-mac)
523 (t eol-mnemonic-undecided))))
524 (if (stringp val)
525 val
526 (char-to-string val))))
527
528 (defun coding-system-lessp (x y)
529 (cond ((eq x 'no-conversion) t)
530 ((eq y 'no-conversion) nil)
531 ((eq x 'emacs-mule) t)
532 ((eq y 'emacs-mule) nil)
533 ((eq x 'undecided) t)
534 ((eq y 'undecided) nil)
535 (t (let ((c1 (coding-system-mnemonic x))
536 (c2 (coding-system-mnemonic y)))
537 (or (< (downcase c1) (downcase c2))
538 (and (not (> (downcase c1) (downcase c2)))
539 (< c1 c2)))))))
540
541 (defun coding-system-equal (coding-system-1 coding-system-2)
542 "Return t if and only if CODING-SYSTEM-1 and CODING-SYSTEM-2 are identical.
543 Two coding systems are identical if two symbols are equal
544 or one is an alias of the other."
545 (or (eq coding-system-1 coding-system-2)
546 (and (equal (coding-system-spec coding-system-1)
547 (coding-system-spec coding-system-2))
548 (let ((eol-type-1 (coding-system-eol-type coding-system-1))
549 (eol-type-2 (coding-system-eol-type coding-system-2)))
550 (or (eq eol-type-1 eol-type-2)
551 (and (vectorp eol-type-1) (vectorp eol-type-2)))))))
552
553 (defun add-to-coding-system-list (coding-system)
554 "Add CODING-SYSTEM to `coding-system-list' while keeping it sorted."
555 (if (or (null coding-system-list)
556 (coding-system-lessp coding-system (car coding-system-list)))
557 (setq coding-system-list (cons coding-system coding-system-list))
558 (let ((len (length coding-system-list))
559 mid (tem coding-system-list))
560 (while (> len 1)
561 (setq mid (nthcdr (/ len 2) tem))
562 (if (coding-system-lessp (car mid) coding-system)
563 (setq tem mid
564 len (- len (/ len 2)))
565 (setq len (/ len 2))))
566 (setcdr tem (cons coding-system (cdr tem))))))
567
568 (defun coding-system-list (&optional base-only)
569 "Return a list of all existing non-subsidiary coding systems.
570 If optional arg BASE-ONLY is non-nil, only base coding systems are listed.
571 The value doesn't include subsidiary coding systems which are what
572 made from bases and aliases automatically for various end-of-line
573 formats (e.g. iso-latin-1-unix, koi8-r-dos)."
574 (let* ((codings (copy-sequence coding-system-list))
575 (tail (cons nil codings)))
576 ;; Remove subsidiary coding systems (eol variants) and alias
577 ;; coding systems (if necessary).
578 (while (cdr tail)
579 (let* ((coding (car (cdr tail)))
580 (aliases (coding-system-get coding 'alias-coding-systems)))
581 (if (or
582 ;; CODING is an eol variant if not in ALIASES.
583 (not (memq coding aliases))
584 ;; CODING is an alias if it is not car of ALIASES.
585 (and base-only (not (eq coding (car aliases)))))
586 (setcdr tail (cdr (cdr tail)))
587 (setq tail (cdr tail)))))
588 codings))
589
590 (defun map-charset-chars (func charset)
591 "Use FUNC to map over all characters in CHARSET for side effects.
592 FUNC is a function of two args, the start and end (inclusive) of a
593 character code range. Thus FUNC should iterate over [START, END]."
594 (let* ((dim (charset-dimension charset))
595 (chars (charset-chars charset))
596 (start (if (= chars 94)
597 33
598 32)))
599 (if (= dim 1)
600 (funcall func
601 (make-char charset start)
602 (make-char charset (+ start chars -1)))
603 (dotimes (i chars)
604 (funcall func
605 (make-char charset (+ i start) start)
606 (make-char charset (+ i start) (+ start chars -1)))))))
607
608 (defalias 'register-char-codings 'ignore "")
609 (make-obsolete 'register-char-codings
610 "it exists just for backward compatibility, and does nothing."
611 "21.3")
612
613 (defconst char-coding-system-table nil
614 "This is an obsolete variable.
615 It exists just for backward compatibility, and the value is always nil.")
616
617 (defun make-subsidiary-coding-system (coding-system)
618 "Make subsidiary coding systems (eol-type variants) of CODING-SYSTEM."
619 (let ((coding-spec (coding-system-spec coding-system))
620 (subsidiaries (vector (intern (format "%s-unix" coding-system))
621 (intern (format "%s-dos" coding-system))
622 (intern (format "%s-mac" coding-system))))
623 (i 0)
624 temp)
625 (while (< i 3)
626 (put (aref subsidiaries i) 'coding-system coding-spec)
627 (put (aref subsidiaries i) 'eol-type i)
628 (add-to-coding-system-list (aref subsidiaries i))
629 (setq coding-system-alist
630 (cons (list (symbol-name (aref subsidiaries i)))
631 coding-system-alist))
632 (setq i (1+ i)))
633 subsidiaries))
634
635 (defun transform-make-coding-system-args (name type &optional doc-string props)
636 "For internal use only.
637 Transform XEmacs style args for `make-coding-system' to Emacs style.
638 Value is a list of transformed arguments."
639 (let ((mnemonic (string-to-char (or (plist-get props 'mnemonic) "?")))
640 (eol-type (plist-get props 'eol-type))
641 properties tmp)
642 (cond
643 ((eq eol-type 'lf) (setq eol-type 'unix))
644 ((eq eol-type 'crlf) (setq eol-type 'dos))
645 ((eq eol-type 'cr) (setq eol-type 'mac)))
646 (if (setq tmp (plist-get props 'post-read-conversion))
647 (setq properties (plist-put properties 'post-read-conversion tmp)))
648 (if (setq tmp (plist-get props 'pre-write-conversion))
649 (setq properties (plist-put properties 'pre-write-conversion tmp)))
650 (cond
651 ((eq type 'shift-jis)
652 `(,name 1 ,mnemonic ,doc-string () ,properties ,eol-type))
653 ((eq type 'iso2022) ; This is not perfect.
654 (if (plist-get props 'escape-quoted)
655 (error "escape-quoted is not supported: %S"
656 `(,name ,type ,doc-string ,props)))
657 (let ((g0 (plist-get props 'charset-g0))
658 (g1 (plist-get props 'charset-g1))
659 (g2 (plist-get props 'charset-g2))
660 (g3 (plist-get props 'charset-g3))
661 (use-roman
662 (and
663 (eq (cadr (assoc 'latin-jisx0201
664 (plist-get props 'input-charset-conversion)))
665 'ascii)
666 (eq (cadr (assoc 'ascii
667 (plist-get props 'output-charset-conversion)))
668 'latin-jisx0201)))
669 (use-oldjis
670 (and
671 (eq (cadr (assoc 'japanese-jisx0208-1978
672 (plist-get props 'input-charset-conversion)))
673 'japanese-jisx0208)
674 (eq (cadr (assoc 'japanese-jisx0208
675 (plist-get props 'output-charset-conversion)))
676 'japanese-jisx0208-1978))))
677 (if (charsetp g0)
678 (if (plist-get props 'force-g0-on-output)
679 (setq g0 `(nil ,g0))
680 (setq g0 `(,g0 t))))
681 (if (charsetp g1)
682 (if (plist-get props 'force-g1-on-output)
683 (setq g1 `(nil ,g1))
684 (setq g1 `(,g1 t))))
685 (if (charsetp g2)
686 (if (plist-get props 'force-g2-on-output)
687 (setq g2 `(nil ,g2))
688 (setq g2 `(,g2 t))))
689 (if (charsetp g3)
690 (if (plist-get props 'force-g3-on-output)
691 (setq g3 `(nil ,g3))
692 (setq g3 `(,g3 t))))
693 `(,name 2 ,mnemonic ,doc-string
694 (,g0 ,g1 ,g2 ,g3
695 ,(plist-get props 'short)
696 ,(not (plist-get props 'no-ascii-eol))
697 ,(not (plist-get props 'no-ascii-cntl))
698 ,(plist-get props 'seven)
699 t
700 ,(not (plist-get props 'lock-shift))
701 ,use-roman
702 ,use-oldjis
703 ,(plist-get props 'no-iso6429)
704 nil nil nil nil)
705 ,properties ,eol-type)))
706 ((eq type 'big5)
707 `(,name 3 ,mnemonic ,doc-string () ,properties ,eol-type))
708 ((eq type 'ccl)
709 `(,name 4 ,mnemonic ,doc-string
710 (,(plist-get props 'decode) . ,(plist-get props 'encode))
711 ,properties ,eol-type))
712 (t
713 (error "unsupported XEmacs style make-coding-style arguments: %S"
714 `(,name ,type ,doc-string ,props))))))
715
716 (defun make-coding-system (coding-system type mnemonic doc-string
717 &optional
718 flags
719 properties
720 eol-type)
721 "Define a new coding system CODING-SYSTEM (symbol).
722 Remaining arguments are TYPE, MNEMONIC, DOC-STRING, FLAGS (optional),
723 and PROPERTIES (optional) which construct a coding-spec of CODING-SYSTEM
724 in the following format:
725 [TYPE MNEMONIC DOC-STRING PLIST FLAGS]
726
727 TYPE is an integer value indicating the type of the coding system as follows:
728 0: Emacs internal format,
729 1: Shift-JIS (or MS-Kanji) used mainly on Japanese PCs,
730 2: ISO-2022 including many variants,
731 3: Big5 used mainly on Chinese PCs,
732 4: private, CCL programs provide encoding/decoding algorithm,
733 5: Raw-text, which means that text contains random 8-bit codes.
734
735 MNEMONIC is a character to be displayed on mode line for the coding system.
736
737 DOC-STRING is a documentation string for the coding system.
738
739 FLAGS specifies more detailed information of the coding system as follows:
740
741 If TYPE is 2 (ISO-2022), FLAGS is a list of these elements:
742 CHARSET0, CHARSET1, CHARSET2, CHARSET3, SHORT-FORM,
743 ASCII-EOL, ASCII-CNTL, SEVEN, LOCKING-SHIFT, SINGLE-SHIFT,
744 USE-ROMAN, USE-OLDJIS, NO-ISO6429, INIT-BOL, DESIGNATION-BOL,
745 SAFE, ACCEPT-LATIN-EXTRA-CODE.
746 CHARSETn are character sets initially designated to Gn graphic registers.
747 If CHARSETn is nil, Gn is never used.
748 If CHARSETn is t, Gn can be used but nothing designated initially.
749 If CHARSETn is a list of character sets, those character sets are
750 designated to Gn on output, but nothing designated to Gn initially.
751 But, character set `ascii' can be designated only to G0.
752 SHORT-FORM non-nil means use short designation sequence on output.
753 ASCII-EOL non-nil means designate ASCII to g0 at end of line on output.
754 ASCII-CNTL non-nil means designate ASCII to g0 before control codes and
755 SPACE on output.
756 SEVEN non-nil means use 7-bit code only on output.
757 LOCKING-SHIFT non-nil means use locking-shift.
758 SINGLE-SHIFT non-nil means use single-shift.
759 USE-ROMAN non-nil means designate JIS0201-1976-Roman instead of ASCII.
760 USE-OLDJIS non-nil means designate JIS0208-1976 instead of JIS0208-1983.
761 NO-ISO6429 non-nil means not use ISO6429's direction specification.
762 INIT-BOL non-nil means any designation state is assumed to be reset
763 to initial at each beginning of line on output.
764 DESIGNATION-BOL non-nil means designation sequences should be placed
765 at beginning of line on output.
766 SAFE non-nil means convert unsafe characters to `?' on output.
767 Characters not specified in the property `safe-charsets' nor
768 `safe-chars' are unsafe.
769 ACCEPT-LATIN-EXTRA-CODE non-nil means code-detection routine accepts
770 a code specified in `latin-extra-code-table' (which see) as a valid
771 code of the coding system.
772
773 If TYPE is 4 (private), FLAGS should be a cons of CCL programs, for
774 decoding and encoding. CCL programs should be specified by their
775 symbols.
776
777 PROPERTIES is an alist of properties vs the corresponding values. The
778 following properties are recognized:
779
780 o post-read-conversion
781
782 The value is a function to call after some text is inserted and
783 decoded by the coding system itself and before any functions in
784 `after-insert-functions' are called. The argument of this
785 function is the same as for a function in
786 `after-insert-file-functions', i.e. LENGTH of the text inserted,
787 with point at the head of the text to be decoded.
788
789 o pre-write-conversion
790
791 The value is a function to call after all functions in
792 `write-region-annotate-functions' and `buffer-file-format' are
793 called, and before the text is encoded by the coding system itself.
794 The arguments to this function are the same as those of a function
795 in `write-region-annotate-functions', i.e. FROM and TO, specifying
796 a region of text.
797
798 o translation-table-for-decode
799
800 The value is a translation table to be applied on decoding. See
801 the function `make-translation-table' for the format of translation
802 table. This is not applicable to type 4 (CCL-based) coding systems.
803
804 o translation-table-for-encode
805
806 The value is a translation table to be applied on encoding. This is
807 not applicable to type 4 (CCL-based) coding systems.
808
809 o safe-chars
810
811 The value is a char table. If a character has non-nil value in it,
812 the character is safely supported by the coding system. This
813 overrides the specification of safe-charsets.
814
815 o safe-charsets
816
817 The value is a list of charsets safely supported by the coding
818 system. The value t means that all charsets Emacs handles are
819 supported. Even if some charset is not in this list, it doesn't
820 mean that the charset can't be encoded in the coding system;
821 it just means that some other receiver of text encoded
822 in the coding system won't be able to handle that charset.
823
824 o mime-charset
825
826 The value is a symbol whose name is the `MIME-charset' parameter of
827 the coding system.
828
829 o mime-text-unsuitable
830
831 A non-nil value means the `mime-charset' property names a charset
832 which is unsuitable for the top-level media type \"text\".
833
834 o valid-codes (meaningful only for a coding system based on CCL)
835
836 The value is a list to indicate valid byte ranges of the encoded
837 file. Each element of the list is an integer or a cons of integer.
838 In the former case, the integer value is a valid byte code. In the
839 latter case, the integers specify the range of valid byte codes.
840
841 o composition (meaningful only when TYPE is 0 or 2)
842
843 If the value is non-nil, the coding system preserves composition
844 information.
845
846 o ascii-incompatible
847
848 If the value is non-nil, the coding system is not compatible
849 with ASCII, which means it encodes or decodes ASCII character
850 string to the different byte sequence.
851
852 These properties are set in PLIST, a property list. This function
853 also sets properties `coding-category' and `alias-coding-systems'
854 automatically.
855
856 EOL-TYPE specifies the EOL type of the coding-system in one of the
857 following formats:
858
859 o symbol (unix, dos, or mac)
860
861 The symbol `unix' means Unix-like EOL (LF), `dos' means
862 DOS-like EOL (CRLF), and `mac' means MAC-like EOL (CR).
863
864 o number (0, 1, or 2)
865
866 The number 0, 1, and 2 mean UNIX, DOS, and MAC-like EOL
867 respectively.
868
869 o vector of coding-systems of length 3
870
871 The EOL type is detected automatically for the coding system.
872 And, according to the detected EOL type, one of the coding
873 systems in the vector is selected. Elements of the vector
874 corresponds to Unix-like EOL, DOS-like EOL, and Mac-like EOL
875 in this order.
876
877 Kludgy features for backward compatibility:
878
879 1. If TYPE is 4 and car or cdr of FLAGS is a vector, the vector is
880 treated as a compiled CCL code.
881
882 2. If PROPERTIES is just a list of character sets, the list is set as
883 a value of `safe-charsets' in PLIST."
884
885 ;; For compatiblity with XEmacs, we check the type of TYPE. If it
886 ;; is a symbol, perhaps, this function is called with XEmacs-style
887 ;; arguments. Here, try to transform that kind of arguments to
888 ;; Emacs style.
889 (if (symbolp type)
890 (let ((args (transform-make-coding-system-args coding-system type
891 mnemonic doc-string)))
892 (setq coding-system (car args)
893 type (nth 1 args)
894 mnemonic (nth 2 args)
895 doc-string (nth 3 args)
896 flags (nth 4 args)
897 properties (nth 5 args)
898 eol-type (nth 6 args))))
899
900 ;; Set a value of `coding-system' property.
901 (let ((coding-spec (make-vector 5 nil))
902 (no-initial-designation t)
903 (no-alternative-designation t)
904 (accept-latin-extra-code nil)
905 coding-category)
906 (if (or (not (integerp type)) (< type 0) (> type 5))
907 (error "TYPE argument must be 0..5"))
908 (if (or (not (integerp mnemonic)) (<= mnemonic ? ) (> mnemonic 127))
909 (error "MNEMONIC argument must be an ASCII printable character"))
910 (aset coding-spec coding-spec-type-idx type)
911 (aset coding-spec coding-spec-mnemonic-idx mnemonic)
912 (aset coding-spec coding-spec-doc-string-idx
913 (purecopy (if (stringp doc-string) doc-string "")))
914 (cond ((= type 0)
915 (setq coding-category 'coding-category-emacs-mule))
916 ((= type 1)
917 (setq coding-category 'coding-category-sjis))
918 ((= type 2) ; ISO2022
919 (let ((i 0)
920 (vec (make-vector 32 nil))
921 (g1-designation nil)
922 (fl flags))
923 (while (< i 4)
924 (let ((charset (car fl)))
925 (if (and no-initial-designation
926 (> i 0)
927 (or (charsetp charset)
928 (and (consp charset)
929 (charsetp (car charset)))))
930 (setq no-initial-designation nil))
931 (if (charsetp charset)
932 (if (= i 1) (setq g1-designation charset))
933 (if (consp charset)
934 (let ((tail charset)
935 elt)
936 (while tail
937 (setq elt (car tail))
938 (if (eq elt t)
939 (setq no-alternative-designation nil)
940 (if (and elt (not (charsetp elt)))
941 (error "Invalid charset: %s" elt)))
942 (setq tail (cdr tail)))
943 (setq g1-designation (car charset)))
944 (if charset
945 (if (eq charset t)
946 (setq no-alternative-designation nil)
947 (error "Invalid charset: %s" charset)))))
948 (aset vec i charset))
949 (setq fl (cdr fl) i (1+ i)))
950 (while (and (< i 32) fl)
951 (aset vec i (car fl))
952 (if (and (= i 16) ; ACCEPT-LATIN-EXTRA-CODE
953 (car fl))
954 (setq accept-latin-extra-code t))
955 (setq fl (cdr fl) i (1+ i)))
956 (aset coding-spec 4 vec)
957 (setq coding-category
958 (if (aref vec 8) ; Use locking-shift.
959 (or (and (aref vec 7) 'coding-category-iso-7-else)
960 'coding-category-iso-8-else)
961 (if (aref vec 7) ; 7-bit only.
962 (if (aref vec 9) ; Use single-shift.
963 'coding-category-iso-7-else
964 (if no-alternative-designation
965 'coding-category-iso-7-tight
966 'coding-category-iso-7))
967 (if (or no-initial-designation
968 (not no-alternative-designation))
969 'coding-category-iso-8-else
970 (if (and (charsetp g1-designation)
971 (= (charset-dimension g1-designation) 2))
972 'coding-category-iso-8-2
973 'coding-category-iso-8-1)))))))
974 ((= type 3)
975 (setq coding-category 'coding-category-big5))
976 ((= type 4) ; private
977 (setq coding-category 'coding-category-ccl)
978 (if (not (consp flags))
979 (error "Invalid FLAGS argument for TYPE 4 (CCL)")
980 (let ((decoder (check-ccl-program
981 (car flags)
982 (intern (format "%s-decoder" coding-system))))
983 (encoder (check-ccl-program
984 (cdr flags)
985 (intern (format "%s-encoder" coding-system)))))
986 (if (and decoder encoder)
987 (aset coding-spec 4 (cons decoder encoder))
988 (error "Invalid FLAGS argument for TYPE 4 (CCL)")))))
989 (t ; i.e. (= type 5)
990 (setq coding-category 'coding-category-raw-text)))
991
992 (let ((plist (list 'coding-category coding-category
993 'alias-coding-systems (list coding-system))))
994 (if no-initial-designation
995 (plist-put plist 'no-initial-designation t))
996 (if (and properties
997 (or (eq properties t)
998 (not (consp (car properties)))))
999 ;; In the old version, the arg PROPERTIES is a list to be
1000 ;; set in PLIST as a value of property `safe-charsets'.
1001 (setq properties (list (cons 'safe-charsets properties))))
1002 ;; In the current version PROPERTIES is a property list.
1003 ;; Reflect it into PLIST one by one while handling safe-chars
1004 ;; specially.
1005 (let ((safe-charsets (cdr (assq 'safe-charsets properties)))
1006 (safe-chars (cdr (assq 'safe-chars properties)))
1007 (l properties)
1008 prop val)
1009 ;; If only safe-charsets is specified, make a char-table from
1010 ;; it, and store that char-table as the value of `safe-chars'.
1011 (if (and (not safe-chars) safe-charsets)
1012 (let (charset)
1013 (if (eq safe-charsets t)
1014 (setq safe-chars t)
1015 (setq safe-chars (make-char-table 'safe-chars))
1016 (while safe-charsets
1017 (setq charset (car safe-charsets)
1018 safe-charsets (cdr safe-charsets))
1019 (cond ((eq charset 'ascii)) ; just ignore
1020 ((eq charset 'eight-bit-control)
1021 (let ((i 128))
1022 (while (< i 160)
1023 (aset safe-chars i t)
1024 (setq i (1+ i)))))
1025 ((eq charset 'eight-bit-graphic)
1026 (let ((i 160))
1027 (while (< i 256)
1028 (aset safe-chars i t)
1029 (setq i (1+ i)))))
1030 (t
1031 (aset safe-chars (make-char charset) t))))
1032 (if accept-latin-extra-code
1033 (let ((i 128))
1034 (while (< i 160)
1035 (if (aref latin-extra-code-table i)
1036 (aset safe-chars i t))
1037 (setq i (1+ i))))))
1038 (setq l (cons (cons 'safe-chars safe-chars) l))))
1039 (while l
1040 (setq prop (car (car l)) val (cdr (car l)) l (cdr l))
1041 (if (eq prop 'safe-chars)
1042 (progn
1043 (if (and (symbolp val)
1044 (get val 'translation-table))
1045 (setq safe-chars (get val 'translation-table)))
1046 (setq val safe-chars)))
1047 (plist-put plist prop val)))
1048 ;; The property `coding-category' may have been set differently
1049 ;; through PROPERTIES.
1050 (setq coding-category (plist-get plist 'coding-category))
1051 (aset coding-spec coding-spec-plist-idx plist))
1052 (put coding-system 'coding-system coding-spec)
1053 (put coding-system 'coding-system-define-form nil)
1054 (put coding-category 'coding-systems
1055 (cons coding-system (get coding-category 'coding-systems))))
1056
1057 ;; Next, set a value of `eol-type' property.
1058 (if (not eol-type)
1059 ;; If EOL-TYPE is nil, set a vector of subsidiary coding
1060 ;; systems, each corresponds to a coding system for the detected
1061 ;; EOL format.
1062 (setq eol-type (make-subsidiary-coding-system coding-system)))
1063 (setq eol-type
1064 (cond ((or (eq eol-type 'unix) (null eol-type))
1065 0)
1066 ((eq eol-type 'dos)
1067 1)
1068 ((eq eol-type 'mac)
1069 2)
1070 ((or (and (vectorp eol-type)
1071 (= (length eol-type) 3))
1072 (and (numberp eol-type)
1073 (and (>= eol-type 0)
1074 (<= eol-type 2))))
1075 eol-type)
1076 (t
1077 (error "Invalid EOL-TYPE spec:%S" eol-type))))
1078 (put coding-system 'eol-type eol-type)
1079
1080 (define-coding-system-internal coding-system)
1081
1082 ;; At last, register CODING-SYSTEM in `coding-system-list' and
1083 ;; `coding-system-alist'.
1084 (add-to-coding-system-list coding-system)
1085 (setq coding-system-alist (cons (list (symbol-name coding-system))
1086 coding-system-alist))
1087
1088 ;; For a coding system of cateogory iso-8-1 and iso-8-2, create
1089 ;; XXX-with-esc variants.
1090 (let ((coding-category (coding-system-category coding-system)))
1091 (if (or (eq coding-category 'coding-category-iso-8-1)
1092 (eq coding-category 'coding-category-iso-8-2))
1093 (let ((esc (intern (concat (symbol-name coding-system) "-with-esc")))
1094 (doc (format "Same as %s but can handle any charsets by ISO's escape sequences." coding-system))
1095 (safe-charsets (assq 'safe-charsets properties))
1096 (mime-charset (assq 'mime-charset properties)))
1097 (if safe-charsets
1098 (setcdr safe-charsets t)
1099 (setq properties (cons (cons 'safe-charsets t) properties)))
1100 (if mime-charset
1101 (setcdr mime-charset nil))
1102 (make-coding-system esc type mnemonic doc
1103 (if (listp (car flags))
1104 (cons (append (car flags) '(t)) (cdr flags))
1105 (cons (list (car flags) t) (cdr flags)))
1106 properties))))
1107
1108 coding-system)
1109
1110 (put 'safe-chars 'char-table-extra-slots 0)
1111
1112 (defun define-coding-system-alias (alias coding-system)
1113 "Define ALIAS as an alias for coding system CODING-SYSTEM."
1114 (put alias 'coding-system (coding-system-spec coding-system))
1115 (put alias 'coding-system-define-form nil)
1116 (add-to-coding-system-list alias)
1117 (setq coding-system-alist (cons (list (symbol-name alias))
1118 coding-system-alist))
1119 (let ((eol-type (coding-system-eol-type coding-system)))
1120 (if (vectorp eol-type)
1121 (progn
1122 (nconc (coding-system-get alias 'alias-coding-systems) (list alias))
1123 (put alias 'eol-type (make-subsidiary-coding-system alias)))
1124 (put alias 'eol-type eol-type))))
1125
1126 (defun merge-coding-systems (first second)
1127 "Fill in any unspecified aspects of coding system FIRST from SECOND.
1128 Return the resulting coding system."
1129 (let ((base (coding-system-base second))
1130 (eol (coding-system-eol-type second)))
1131 ;; If FIRST doesn't specify text conversion, merge with that of SECOND.
1132 (if (eq (coding-system-base first) 'undecided)
1133 (setq first (coding-system-change-text-conversion first base)))
1134 ;; If FIRST doesn't specify eol conversion, merge with that of SECOND.
1135 (if (and (vectorp (coding-system-eol-type first))
1136 (numberp eol) (>= eol 0) (<= eol 2))
1137 (setq first (coding-system-change-eol-conversion
1138 first eol)))
1139 first))
1140
1141 (defun autoload-coding-system (symbol form)
1142 "Define SYMBOL as a coding-system that is defined on demand.
1143
1144 FROM is a form to evaluate to define the coding-system."
1145 (put symbol 'coding-system-define-form form)
1146 (setq coding-system-alist (cons (list (symbol-name symbol))
1147 coding-system-alist))
1148 (dolist (elt '("-unix" "-dos" "-mac"))
1149 (let ((name (concat (symbol-name symbol) elt)))
1150 (put (intern name) 'coding-system-define-form form)
1151 (setq coding-system-alist (cons (list name) coding-system-alist)))))
1152
1153 (defun set-buffer-file-coding-system (coding-system &optional force nomodify)
1154 "Set the file coding-system of the current buffer to CODING-SYSTEM.
1155 This means that when you save the buffer, it will be converted
1156 according to CODING-SYSTEM. For a list of possible values of CODING-SYSTEM,
1157 use \\[list-coding-systems].
1158
1159 If CODING-SYSTEM leaves the text conversion unspecified, or if it
1160 leaves the end-of-line conversion unspecified, FORCE controls what to
1161 do. If FORCE is nil, get the unspecified aspect (or aspects) from the
1162 buffer's previous `buffer-file-coding-system' value (if it is
1163 specified there). Otherwise, leave it unspecified.
1164
1165 This marks the buffer modified so that the succeeding \\[save-buffer]
1166 surely saves the buffer with CODING-SYSTEM. From a program, if you
1167 don't want to mark the buffer modified, specify t for NOMODIFY.
1168 If you know exactly what coding system you want to use,
1169 just set the variable `buffer-file-coding-system' directly."
1170 (interactive "zCoding system for saving file (default nil): \nP")
1171 (check-coding-system coding-system)
1172 (if (and coding-system buffer-file-coding-system (null force))
1173 (setq coding-system
1174 (merge-coding-systems coding-system buffer-file-coding-system)))
1175 (setq buffer-file-coding-system coding-system)
1176 ;; This is in case of an explicit call. Normally, `normal-mode' and
1177 ;; `set-buffer-major-mode-hook' take care of setting the table.
1178 (if (fboundp 'ucs-set-table-for-input) ; don't lose when building
1179 (ucs-set-table-for-input))
1180 (unless nomodify
1181 (set-buffer-modified-p t))
1182 (force-mode-line-update))
1183
1184 (defun revert-buffer-with-coding-system (coding-system &optional force)
1185 "Visit the current buffer's file again using coding system CODING-SYSTEM.
1186 For a list of possible values of CODING-SYSTEM, use \\[list-coding-systems].
1187
1188 If CODING-SYSTEM leaves the text conversion unspecified, or if it
1189 leaves the end-of-line conversion unspecified, FORCE controls what to
1190 do. If FORCE is nil, get the unspecified aspect (or aspects) from the
1191 buffer's previous `buffer-file-coding-system' value (if it is
1192 specified there). Otherwise, determine it from the file contents as
1193 usual for visiting a file."
1194 (interactive "zCoding system for visited file (default nil): \nP")
1195 (check-coding-system coding-system)
1196 (if (and coding-system buffer-file-coding-system (null force))
1197 (setq coding-system
1198 (merge-coding-systems coding-system buffer-file-coding-system)))
1199 (let ((coding-system-for-read coding-system))
1200 (revert-buffer)))
1201
1202 (defun set-file-name-coding-system (coding-system)
1203 "Set coding system for decoding and encoding file names to CODING-SYSTEM.
1204 It actually just set the variable `file-name-coding-system' (which
1205 see) to CODING-SYSTEM."
1206 (interactive "zCoding system for file names (default nil): ")
1207 (check-coding-system coding-system)
1208 (if (and coding-system
1209 (coding-system-get coding-system 'ascii-incompatible))
1210 (error "%s is not ASCII-compatible" coding-system))
1211 (setq file-name-coding-system coding-system))
1212
1213 (defvar default-terminal-coding-system nil
1214 "Default value for the terminal coding system.
1215 This is normally set according to the selected language environment.
1216 See also the command `set-terminal-coding-system'.")
1217
1218 (defun set-terminal-coding-system (coding-system &optional display)
1219 "Set coding system of terminal output to CODING-SYSTEM.
1220 All text output to DISPLAY will be encoded
1221 with the specified coding system.
1222
1223 For a list of possible values of CODING-SYSTEM, use \\[list-coding-systems].
1224 The default is determined by the selected language environment
1225 or by the previous use of this command.
1226
1227 DISPLAY may be a display id, a frame, or nil for the selected frame's display.
1228 The setting has no effect on graphical displays."
1229 (interactive
1230 (list (let ((default (if (and (not (terminal-coding-system))
1231 default-terminal-coding-system)
1232 default-terminal-coding-system)))
1233 (read-coding-system
1234 (format "Coding system for terminal display (default %s): "
1235 default)
1236 default))))
1237 (if (and (not coding-system)
1238 (not (terminal-coding-system)))
1239 (setq coding-system default-terminal-coding-system))
1240 (if coding-system
1241 (setq default-terminal-coding-system coding-system))
1242 (set-terminal-coding-system-internal coding-system display)
1243 (redraw-frame (selected-frame)))
1244
1245 (defvar default-keyboard-coding-system nil
1246 "Default value of the keyboard coding system.
1247 This is normally set according to the selected language environment.
1248 See also the command `set-keyboard-coding-system'.")
1249
1250 (defun set-keyboard-coding-system (coding-system &optional display)
1251 "Set coding system for keyboard input on DISPLAY to CODING-SYSTEM.
1252 In addition, this command calls `encoded-kbd-setup-display' to set up the
1253 translation of keyboard input events to the specified coding system.
1254
1255 For a list of possible values of CODING-SYSTEM, use \\[list-coding-systems].
1256 The default is determined by the selected language environment
1257 or by the previous use of this command.
1258
1259 DISPLAY may be a display id, a frame, or nil for the selected frame's display.
1260 The setting has no effect on graphical displays."
1261 (interactive
1262 (list (let ((default (if (and (not (keyboard-coding-system))
1263 default-keyboard-coding-system)
1264 default-keyboard-coding-system)))
1265 (read-coding-system
1266 (format "Coding system for keyboard input (default %s): "
1267 default)
1268 default))))
1269 (if (and (not coding-system)
1270 (not (keyboard-coding-system)))
1271 (setq coding-system default-keyboard-coding-system))
1272 (if coding-system
1273 (setq default-keyboard-coding-system coding-system))
1274 (if (and coding-system
1275 (coding-system-get coding-system 'ascii-incompatible))
1276 (error "%s is not ASCII-compatible" coding-system))
1277 (set-keyboard-coding-system-internal coding-system display)
1278 (setq keyboard-coding-system coding-system)
1279 (encoded-kbd-setup-display display))
1280
1281 (defcustom keyboard-coding-system nil
1282 "Specify coding system for keyboard input.
1283 If you set this on a terminal which can't distinguish Meta keys from
1284 8-bit characters, you will have to use ESC to type Meta characters.
1285 See Info node `Specify Coding' and Info node `Single-Byte Character Support'.
1286
1287 On non-windowing terminals, this is set from the locale by default.
1288
1289 Setting this variable directly does not take effect;
1290 use either \\[customize] or \\[set-keyboard-coding-system]."
1291 :type '(coding-system :tag "Coding system")
1292 :link '(info-link "(emacs)Specify Coding")
1293 :link '(info-link "(emacs)Single-Byte Character Support")
1294 :set (lambda (symbol value)
1295 ;; Don't load encoded-kb unnecessarily.
1296 (if (or value (boundp 'encoded-kbd-setup-display))
1297 (set-keyboard-coding-system value)
1298 (set-default 'keyboard-coding-system nil))) ; must initialize
1299 :version "22.1"
1300 :group 'keyboard
1301 :group 'mule)
1302
1303 (defun set-buffer-process-coding-system (decoding encoding)
1304 "Set coding systems for the process associated with the current buffer.
1305 DECODING is the coding system to be used to decode input from the process,
1306 ENCODING is the coding system to be used to encode output to the process.
1307
1308 For a list of possible values of CODING-SYSTEM, use \\[list-coding-systems]."
1309 (interactive
1310 "zCoding-system for output from the process: \nzCoding-system for input to the process: ")
1311 (let ((proc (get-buffer-process (current-buffer))))
1312 (if (null proc)
1313 (error "No process")
1314 (check-coding-system decoding)
1315 (check-coding-system encoding)
1316 (set-process-coding-system proc decoding encoding)))
1317 (force-mode-line-update))
1318
1319 (defalias 'set-clipboard-coding-system 'set-selection-coding-system)
1320
1321 (defun set-selection-coding-system (coding-system)
1322 "Make CODING-SYSTEM used for communicating with other X clients.
1323 When sending or receiving text via cut_buffer, selection, and clipboard,
1324 the text is encoded or decoded by CODING-SYSTEM."
1325 (interactive "zCoding system for X selection: ")
1326 (check-coding-system coding-system)
1327 (setq selection-coding-system coding-system))
1328
1329 ;; Coding system lastly specified by the command
1330 ;; set-next-selection-coding-system.
1331 (defvar last-next-selection-coding-system nil)
1332
1333 (defun set-next-selection-coding-system (coding-system)
1334 "Make CODING-SYSTEM used for the next communication with other X clients.
1335 This setting is effective for the next communication only."
1336 (interactive
1337 (list (read-coding-system
1338 (if last-next-selection-coding-system
1339 (format "Coding system for the next X selection (default %S): "
1340 last-next-selection-coding-system)
1341 "Coding system for the next X selection: ")
1342 last-next-selection-coding-system)))
1343 (if coding-system
1344 (setq last-next-selection-coding-system coding-system)
1345 (setq coding-system last-next-selection-coding-system))
1346 (check-coding-system coding-system)
1347
1348 (setq next-selection-coding-system coding-system))
1349
1350 (defun set-coding-priority (arg)
1351 "Set priority of coding categories according to ARG.
1352 ARG is a list of coding categories ordered by priority."
1353 (let ((l arg)
1354 (current-list (copy-sequence coding-category-list)))
1355 ;; Check the validity of ARG while deleting coding categories in
1356 ;; ARG from CURRENT-LIST. We assume that CODING-CATEGORY-LIST
1357 ;; contains all coding categories.
1358 (while l
1359 (if (or (null (get (car l) 'coding-category-index))
1360 (null (memq (car l) current-list)))
1361 (error "Invalid or duplicated element in argument: %s" arg))
1362 (setq current-list (delq (car l) current-list))
1363 (setq l (cdr l)))
1364 ;; Update `coding-category-list' and return it.
1365 (setq coding-category-list (append arg current-list))
1366 (set-coding-priority-internal)))
1367
1368 ;;; X selections
1369
1370 (defvar ctext-non-standard-encodings-alist
1371 '(("big5-0" big5 2 (chinese-big5-1 chinese-big5-2))
1372 ("ISO8859-14" iso-8859-14 1 latin-iso8859-14)
1373 ("ISO8859-15" iso-8859-15 1 latin-iso8859-15))
1374 "Alist of non-standard encoding names vs the corresponding usages in CTEXT.
1375
1376 It controls how extended segments of a compound text are handled
1377 by the coding system `compound-text-with-extensions'.
1378
1379 Each element has the form (ENCODING-NAME CODING-SYSTEM N-OCTET CHARSET).
1380
1381 ENCODING-NAME is an encoding name of an \"extended segments\".
1382
1383 CODING-SYSTEM is the coding-system to encode (or decode) the
1384 characters into (or from) the extended segment.
1385
1386 N-OCTET is the number of octets (bytes) that encodes a character
1387 in the segment. It can be 0 (meaning the number of octets per
1388 character is variable), 1, 2, 3, or 4.
1389
1390 CHARSET is a charater set containing characters that are encoded
1391 in the segment. It can be a list of character sets. It can also
1392 be a char-table, in which case characters that have non-nil value
1393 in the char-table are the target.
1394
1395 On decoding CTEXT, all encoding names listed here are recognized.
1396
1397 On encoding CTEXT, encoding names in the variable
1398 `ctext-non-standard-encodings' (which see) and in the information
1399 listed for the current language environment under the key
1400 `ctext-non-standard-encodings' are used.")
1401
1402 (defvar ctext-non-standard-encodings
1403 '("big5-0")
1404 "List of non-standard encoding names used in extended segments of CTEXT.
1405 Each element must be one of the names listed in the variable
1406 `ctext-non-standard-encodings-alist' (which see).")
1407
1408 (defvar ctext-non-standard-encodings-regexp
1409 (string-to-multibyte
1410 (concat
1411 ;; For non-standard encodings.
1412 "\\(\e%/[0-4][\200-\377][\200-\377]\\([^\002]+\\)\002\\)"
1413 "\\|"
1414 ;; For UTF-8 encoding.
1415 "\\(\e%G[^\e]*\e%@\\)")))
1416
1417 ;; Functions to support "Non-Standard Character Set Encodings" defined
1418 ;; by the COMPOUND-TEXT spec. They also support "The UTF-8 encoding"
1419 ;; described in the section 7 of the documentation of COMPOUND-TEXT
1420 ;; distributed with XFree86.
1421
1422 (defun ctext-post-read-conversion (len)
1423 "Decode LEN characters encoded as Compound Text with Extended Segments."
1424 (save-match-data
1425 (save-restriction
1426 (let ((case-fold-search nil)
1427 (in-workbuf (string= (buffer-name) " *code-converting-work*"))
1428 last-coding-system-used
1429 pos bytes)
1430 (or in-workbuf
1431 (narrow-to-region (point) (+ (point) len)))
1432 (if in-workbuf
1433 (set-buffer-multibyte t))
1434 (while (re-search-forward ctext-non-standard-encodings-regexp
1435 nil 'move)
1436 (setq pos (match-beginning 0))
1437 (if (match-beginning 1)
1438 ;; ESC % / [0-4] M L --ENCODING-NAME-- \002 --BYTES--
1439 (let* ((M (char-after (+ pos 4)))
1440 (L (char-after (+ pos 5)))
1441 (encoding (match-string 2))
1442 (encoding-info (assoc-string
1443 encoding
1444 ctext-non-standard-encodings-alist t))
1445 (coding (if encoding-info
1446 (nth 1 encoding-info)
1447 (setq encoding (intern (downcase encoding)))
1448 (and (coding-system-p encoding)
1449 encoding))))
1450 (setq bytes (- (+ (* (- M 128) 128) (- L 128))
1451 (- (point) (+ pos 6))))
1452 (when coding
1453 (delete-region pos (point))
1454 (forward-char bytes)
1455 (decode-coding-region (- (point) bytes) (point) coding)))
1456 ;; ESC % G --UTF-8-BYTES-- ESC % @
1457 (delete-char -3)
1458 (delete-region pos (+ pos 3))
1459 (decode-coding-region pos (point) 'utf-8))))
1460 (goto-char (point-min))
1461 (- (point-max) (point)))))
1462
1463 ;; Return a char table of extended segment usage for each character.
1464 ;; Each value of the char table is nil, one of the elements of
1465 ;; `ctext-non-standard-encodings-alist', or the symbol `utf-8'.
1466
1467 (defun ctext-non-standard-encodings-table ()
1468 (let ((table (make-char-table 'translation-table)))
1469 (aset table (make-char 'mule-unicode-0100-24ff) 'utf-8)
1470 (aset table (make-char 'mule-unicode-2500-33ff) 'utf-8)
1471 (aset table (make-char 'mule-unicode-e000-ffff) 'utf-8)
1472 (dolist (encoding (reverse
1473 (append
1474 (get-language-info current-language-environment
1475 'ctext-non-standard-encodings)
1476 ctext-non-standard-encodings)))
1477 (let* ((slot (assoc encoding ctext-non-standard-encodings-alist))
1478 (charset (nth 3 slot)))
1479 (if charset
1480 (cond ((charsetp charset)
1481 (aset table (make-char charset) slot))
1482 ((listp charset)
1483 (dolist (elt charset)
1484 (aset table (make-char elt) slot)))
1485 ((char-table-p charset)
1486 (map-char-table #'(lambda (k v)
1487 (if (and v (> k 128)) (aset table k slot)))
1488 charset))))))
1489 table))
1490
1491 (defun ctext-pre-write-conversion (from to)
1492 "Encode characters between FROM and TO as Compound Text w/Extended Segments.
1493
1494 If FROM is a string, or if the current buffer is not the one set up for us
1495 by encode-coding-string, generate a new temp buffer, insert the
1496 text, and convert it in the temporary buffer. Otherwise, convert in-place."
1497 (save-match-data
1498 (let ((workbuf (get-buffer-create " *code-conversion-work*")))
1499 ;; Setup a working buffer if necessary.
1500 (cond ((stringp from)
1501 (set-buffer workbuf)
1502 (erase-buffer)
1503 (set-buffer-multibyte (multibyte-string-p from))
1504 (insert from))
1505 ((not (eq (current-buffer) workbuf))
1506 (let ((buf (current-buffer))
1507 (multibyte enable-multibyte-characters))
1508 (set-buffer workbuf)
1509 (erase-buffer)
1510 (set-buffer-multibyte multibyte)
1511 (insert-buffer-substring buf from to)))))
1512
1513 ;; Now we can encode the whole buffer.
1514 (let ((encoding-table (ctext-non-standard-encodings-table))
1515 last-coding-system-used
1516 last-pos last-encoding-info
1517 encoding-info end-pos)
1518 (goto-char (setq last-pos (point-min)))
1519 (setq end-pos (point-marker))
1520 (while (re-search-forward "[^\000-\177]+" nil t)
1521 ;; Found a sequence of non-ASCII characters.
1522 (setq last-pos (match-beginning 0)
1523 last-encoding-info (aref encoding-table (char-after last-pos)))
1524 (set-marker end-pos (match-end 0))
1525 (goto-char (1+ last-pos))
1526 (catch 'tag
1527 (while t
1528 (setq encoding-info
1529 (if (< (point) end-pos)
1530 (aref encoding-table (following-char))))
1531 (unless (eq last-encoding-info encoding-info)
1532 (cond ((consp last-encoding-info)
1533 ;; Encode the previous range using an extended
1534 ;; segment.
1535 (let ((encoding-name (car last-encoding-info))
1536 (coding-system (nth 1 last-encoding-info))
1537 (noctets (nth 2 last-encoding-info))
1538 len)
1539 (encode-coding-region last-pos (point) coding-system)
1540 (setq len (+ (length encoding-name) 1
1541 (- (point) last-pos)))
1542 (save-excursion
1543 (goto-char last-pos)
1544 (insert (string-to-multibyte
1545 (format "\e%%/%d%c%c%s\ 2"
1546 noctets
1547 (+ (/ len 128) 128)
1548 (+ (% len 128) 128)
1549 encoding-name))))))
1550 ((eq last-encoding-info 'utf-8)
1551 ;; Encode the previous range using UTF-8 encoding
1552 ;; extention.
1553 (encode-coding-region last-pos (point) 'mule-utf-8)
1554 (save-excursion
1555 (goto-char last-pos)
1556 (insert "\e%G"))
1557 (insert "\e%@")))
1558 (setq last-pos (point)
1559 last-encoding-info encoding-info))
1560 (if (< (point) end-pos)
1561 (forward-char 1)
1562 (throw 'tag nil)))))
1563 (set-marker end-pos nil)
1564 (goto-char (point-min))))
1565 ;; Must return nil, as build_annotations_2 expects that.
1566 nil)
1567
1568 ;;; FILE I/O
1569
1570 (defcustom auto-coding-alist
1571 '(("\\.\\(arc\\|zip\\|lzh\\|zoo\\|[jew]ar\\|xpi\\)\\'" . no-conversion)
1572 ("\\.\\(ARC\\|ZIP\\|LZH\\|ZOO\\|[JEW]AR\\|XPI\\)\\'" . no-conversion)
1573 ("\\.\\(sx[dmicw]\\|tar\\|tgz\\)\\'" . no-conversion)
1574 ("\\.\\(gz\\|Z\\|bz\\|bz2\\|gpg\\)\\'" . no-conversion)
1575 ("\\.\\(jpe?g\\|png\\|gif\\|tiff?\\|p[bpgn]m\\)\\'" . no-conversion)
1576 ("/#[^/]+#\\'" . emacs-mule))
1577 "Alist of filename patterns vs corresponding coding systems.
1578 Each element looks like (REGEXP . CODING-SYSTEM).
1579 A file whose name matches REGEXP is decoded by CODING-SYSTEM on reading.
1580
1581 The settings in this alist take priority over `coding:' tags
1582 in the file (see the function `set-auto-coding')
1583 and the contents of `file-coding-system-alist'."
1584 :group 'files
1585 :group 'mule
1586 :type '(repeat (cons (regexp :tag "File name regexp")
1587 (symbol :tag "Coding system"))))
1588
1589 (defcustom auto-coding-regexp-alist
1590 '(("^BABYL OPTIONS:[ \t]*-\\*-[ \t]*rmail[ \t]*-\\*-" . no-conversion))
1591 "Alist of patterns vs corresponding coding systems.
1592 Each element looks like (REGEXP . CODING-SYSTEM).
1593 A file whose first bytes match REGEXP is decoded by CODING-SYSTEM on reading.
1594
1595 The settings in this alist take priority over `coding:' tags
1596 in the file (see the function `set-auto-coding')
1597 and the contents of `file-coding-system-alist'."
1598 :group 'files
1599 :group 'mule
1600 :type '(repeat (cons (regexp :tag "Regexp")
1601 (symbol :tag "Coding system"))))
1602
1603 (defun auto-coding-regexp-alist-lookup (from to)
1604 "Lookup `auto-coding-regexp-alist' for the contents of the current buffer.
1605 The value is a coding system is specified for the region FROM and TO,
1606 or nil."
1607 (save-excursion
1608 (goto-char from)
1609 (let ((alist auto-coding-regexp-alist)
1610 coding-system)
1611 (while (and alist (not coding-system))
1612 (let ((regexp (car (car alist))))
1613 (if enable-multibyte-characters
1614 (setq regexp (string-to-multibyte regexp)))
1615 (if (re-search-forward regexp to t)
1616 (setq coding-system (cdr (car alist)))
1617 (setq alist (cdr alist)))))
1618 coding-system)))
1619
1620 ;; See the bottom of this file for built-in auto coding functions.
1621 (defcustom auto-coding-functions '(sgml-xml-auto-coding-function
1622 sgml-html-meta-auto-coding-function)
1623 "A list of functions which attempt to determine a coding system.
1624
1625 Each function in this list should be written to operate on the
1626 current buffer, but should not modify it in any way. The buffer
1627 will contain undecoded text of parts of the file. Each function
1628 should take one argument, SIZE, which says how many
1629 characters (starting from point) it should look at.
1630
1631 If one of these functions succeeds in determining a coding
1632 system, it should return that coding system. Otherwise, it
1633 should return nil.
1634
1635 If a file has a `coding:' tag, that takes precedence over these
1636 functions, so they won't be called at all."
1637 :group 'files
1638 :group 'mule
1639 :type '(repeat function))
1640
1641 (defvar set-auto-coding-for-load nil
1642 "Non-nil means look for `load-coding' property instead of `coding'.
1643 This is used for loading and byte-compiling Emacs Lisp files.")
1644
1645 (defun auto-coding-alist-lookup (filename)
1646 "Return the coding system specified by `auto-coding-alist' for FILENAME."
1647 (let ((alist auto-coding-alist)
1648 (case-fold-search (memq system-type '(vax-vms windows-nt ms-dos cygwin)))
1649 coding-system)
1650 (while (and alist (not coding-system))
1651 (if (string-match (car (car alist)) filename)
1652 (setq coding-system (cdr (car alist)))
1653 (setq alist (cdr alist))))
1654 coding-system))
1655
1656 (defun find-auto-coding (filename size)
1657 "Find a coding system for a file FILENAME of which SIZE bytes follow point.
1658 These bytes should include at least the first 1k of the file
1659 and the last 3k of the file, but the middle may be omitted.
1660
1661 The function checks FILENAME against the variable `auto-coding-alist'.
1662 If FILENAME doesn't match any entries in the variable, it checks the
1663 contents of the current buffer following point against
1664 `auto-coding-regexp-alist'. If no match is found, it checks for a
1665 `coding:' tag in the first one or two lines following point. If no
1666 `coding:' tag is found, it checks any local variables list in the last
1667 3K bytes out of the SIZE bytes. Finally, if none of these methods
1668 succeed, it checks to see if any function in `auto-coding-functions'
1669 gives a match.
1670
1671 If a coding system is specifed, the return value is a
1672 cons (CODING . SOURCE), where CODING is the specified coding
1673 system and SOURCE is a symbol `auto-coding-alist',
1674 `auto-coding-regexp-alist', `coding:', or `auto-coding-functions'
1675 indicating by what CODING is specified. Note that the validity
1676 of CODING is not checked; it's callers responsibility to check
1677 it.
1678
1679 If nothing is specified, the return value is nil."
1680 (or (let ((coding-system (auto-coding-alist-lookup filename)))
1681 (if coding-system
1682 (cons coding-system 'auto-coding-alist)))
1683 ;; Try using `auto-coding-regexp-alist'.
1684 (let ((coding-system (auto-coding-regexp-alist-lookup (point)
1685 (+ (point) size))))
1686 (if coding-system
1687 (cons coding-system 'auto-coding-regexp-alist)))
1688 (let* ((case-fold-search t)
1689 (head-start (point))
1690 (head-end (+ head-start (min size 1024)))
1691 (tail-start (+ head-start (max (- size 3072) 0)))
1692 (tail-end (+ head-start size))
1693 coding-system head-found tail-found pos)
1694 ;; Try a short cut by searching for the string "coding:"
1695 ;; and for "unibyte:" at the head and tail of SIZE bytes.
1696 (setq head-found (or (search-forward "coding:" head-end t)
1697 (search-forward "unibyte:" head-end t)))
1698 (if (and head-found (> head-found tail-start))
1699 ;; Head and tail are overlapped.
1700 (setq tail-found head-found)
1701 (goto-char tail-start)
1702 (setq tail-found (or (search-forward "coding:" tail-end t)
1703 (search-forward "unibyte:" tail-end t))))
1704
1705 ;; At first check the head.
1706 (when head-found
1707 (goto-char head-start)
1708 (setq head-end (set-auto-mode-1))
1709 (setq head-start (point))
1710 (when (and head-end (< head-found head-end))
1711 (goto-char head-start)
1712 (when (and set-auto-coding-for-load
1713 (re-search-forward
1714 "\\(.*;\\)?[ \t]*unibyte:[ \t]*\\([^ ;]+\\)"
1715 head-end t))
1716 (setq coding-system 'raw-text))
1717 (when (and (not coding-system)
1718 (re-search-forward
1719 "\\(.*;\\)?[ \t]*coding:[ \t]*\\([^ ;]+\\)"
1720 head-end t))
1721 (setq coding-system (intern (match-string 2))))))
1722
1723 ;; If no coding: tag in the head, check the tail.
1724 ;; Here we must pay attention to the case that the end-of-line
1725 ;; is just "\r" and we can't use "^" nor "$" in regexp.
1726 (when (and tail-found (not coding-system))
1727 (goto-char tail-start)
1728 (re-search-forward "[\r\n]\^L" nil t)
1729 (if (re-search-forward
1730 "[\r\n]\\([^[\r\n]*\\)[ \t]*Local Variables:[ \t]*\\([^\r\n]*\\)[\r\n]"
1731 tail-end t)
1732 ;; The prefix is what comes before "local variables:" in its
1733 ;; line. The suffix is what comes after "local variables:"
1734 ;; in its line.
1735 (let* ((prefix (regexp-quote (match-string 1)))
1736 (suffix (regexp-quote (match-string 2)))
1737 (re-coding
1738 (concat
1739 "[\r\n]" prefix
1740 ;; N.B. without the \n below, the regexp can
1741 ;; eat newlines.
1742 "[ \t]*coding[ \t]*:[ \t]*\\([^ \t\r\n]+\\)[ \t]*"
1743 suffix "[\r\n]"))
1744 (re-unibyte
1745 (concat
1746 "[\r\n]" prefix
1747 "[ \t]*unibyte[ \t]*:[ \t]*\\([^ \t\r\n]+\\)[ \t]*"
1748 suffix "[\r\n]"))
1749 (re-end
1750 (concat "[\r\n]" prefix "[ \t]*End *:[ \t]*" suffix
1751 "[\r\n]?"))
1752 (pos (1- (point))))
1753 (forward-char -1) ; skip back \r or \n.
1754 (re-search-forward re-end tail-end 'move)
1755 (setq tail-end (point))
1756 (goto-char pos)
1757 (when (and set-auto-coding-for-load
1758 (re-search-forward re-unibyte tail-end t))
1759 (setq coding-system 'raw-text))
1760 (when (and (not coding-system)
1761 (re-search-forward re-coding tail-end t))
1762 (setq coding-system (intern (match-string 1)))))))
1763 (if coding-system
1764 (cons coding-system :coding)))
1765 ;; Finally, try all the `auto-coding-functions'.
1766 (let ((funcs auto-coding-functions)
1767 (coding-system nil))
1768 (while (and funcs (not coding-system))
1769 (setq coding-system (condition-case e
1770 (save-excursion
1771 (goto-char (point-min))
1772 (funcall (pop funcs) size))
1773 (error nil))))
1774 (if coding-system
1775 (cons coding-system 'auto-coding-functions)))))
1776
1777 (defun set-auto-coding (filename size)
1778 "Return coding system for a file FILENAME of which SIZE bytes follow point.
1779 See `find-auto-coding' for how the coding system is found.
1780 Return nil if an invalid coding system is found.
1781
1782 The variable `set-auto-coding-function' (which see) is set to this
1783 function by default."
1784 (let ((found (find-auto-coding filename size)))
1785 (if (and found (coding-system-p (car found)))
1786 (car found))))
1787
1788 (setq set-auto-coding-function 'set-auto-coding)
1789
1790 ;; This variable is set in these two cases:
1791 ;; (1) A file is read by a coding system specified explicitly.
1792 ;; after-insert-file-set-coding sets this value to
1793 ;; coding-system-for-read.
1794 ;; (2) A buffer is saved.
1795 ;; After writing, basic-save-buffer-1 sets this value to
1796 ;; last-coding-system-used.
1797 ;; This variable is used for decoding in revert-buffer.
1798 (defvar buffer-file-coding-system-explicit nil
1799 "The file coding system explicitly specified for the current buffer.
1800 Internal use only.")
1801 (make-variable-buffer-local 'buffer-file-coding-system-explicit)
1802 (put 'buffer-file-coding-system-explicit 'permanent-local t)
1803
1804 (defun after-insert-file-set-coding (inserted &optional visit)
1805 "Set `buffer-file-coding-system' of current buffer after text is inserted.
1806 INSERTED is the number of characters that were inserted, as figured
1807 in the situation before this function. Return the number of characters
1808 inserted, as figured in the situation after. The two numbers can be
1809 different if the buffer has become unibyte.
1810 The optional second arg VISIT non-nil means that we are visiting a file."
1811 (if (and visit
1812 coding-system-for-read
1813 (not (eq coding-system-for-read 'auto-save-coding)))
1814 (setq buffer-file-coding-system-explicit coding-system-for-read))
1815 (if last-coding-system-used
1816 (let ((coding-system
1817 (find-new-buffer-file-coding-system last-coding-system-used))
1818 (modified-p (buffer-modified-p)))
1819 (when coding-system
1820 ;; Tell set-buffer-file-coding-system not to mark the file
1821 ;; as modified; we just read it, and it's supposed to be unmodified.
1822 ;; Marking it modified would try to lock it, which would
1823 ;; check the modtime, and we don't want to do that again now.
1824 (set-buffer-file-coding-system coding-system t t)
1825 (if (and enable-multibyte-characters
1826 (or (eq coding-system 'no-conversion)
1827 (eq (coding-system-type coding-system) 5))
1828 ;; If buffer was unmodified and the size is the
1829 ;; same as INSERTED, we must be visiting it.
1830 (not modified-p)
1831 (= (buffer-size) inserted))
1832 ;; For coding systems no-conversion and raw-text...,
1833 ;; edit the buffer as unibyte.
1834 (let ((pos-marker (copy-marker (+ (point) inserted)))
1835 ;; Prevent locking.
1836 (buffer-file-name nil))
1837 (set-buffer-multibyte nil)
1838 (setq inserted (- pos-marker (point)))))
1839 (set-buffer-modified-p modified-p))))
1840 inserted)
1841
1842 ;; The coding-spec and eol-type of coding-system returned is decided
1843 ;; independently in the following order.
1844 ;; 1. That of buffer-file-coding-system locally bound.
1845 ;; 2. That of CODING.
1846
1847 (defun find-new-buffer-file-coding-system (coding)
1848 "Return a coding system for a buffer when a file of CODING is inserted.
1849 The local variable `buffer-file-coding-system' of the current buffer
1850 is set to the returned value.
1851 Return nil if there's no need to set `buffer-file-coding-system'."
1852 (let (local-coding local-eol
1853 found-coding found-eol
1854 new-coding new-eol)
1855 (if (null coding)
1856 ;; Nothing found about coding.
1857 nil
1858
1859 ;; Get information of `buffer-file-coding-system' in LOCAL-EOL
1860 ;; and LOCAL-CODING.
1861 (setq local-eol (coding-system-eol-type buffer-file-coding-system))
1862 (if (null (numberp local-eol))
1863 ;; But eol-type is not yet set.
1864 (setq local-eol nil))
1865 (if (and buffer-file-coding-system
1866 (not (eq (coding-system-type buffer-file-coding-system) t)))
1867 ;; This is not `undecided'.
1868 (setq local-coding (coding-system-base buffer-file-coding-system)))
1869
1870 (if (and (local-variable-p 'buffer-file-coding-system)
1871 local-eol local-coding)
1872 ;; The current buffer has already set full coding-system, we
1873 ;; had better not change it.
1874 nil
1875
1876 (setq found-eol (coding-system-eol-type coding))
1877 (if (null (numberp found-eol))
1878 ;; But eol-type is not found.
1879 ;; If EOL conversions are inhibited, force unix eol-type.
1880 (setq found-eol (if inhibit-eol-conversion 0)))
1881 (if (eq (coding-system-type coding) t)
1882 (setq found-coding 'undecided)
1883 (setq found-coding (coding-system-base coding)))
1884
1885 (if (and (not found-eol) (eq found-coding 'undecided))
1886 ;; No valid coding information found.
1887 nil
1888
1889 ;; Some coding information (eol or text) found.
1890
1891 ;; The local setting takes precedence over the found one.
1892 (setq new-coding (if (local-variable-p 'buffer-file-coding-system)
1893 (or local-coding found-coding)
1894 (or found-coding local-coding)))
1895 (setq new-eol (if (local-variable-p 'buffer-file-coding-system)
1896 (or local-eol found-eol)
1897 (or found-eol local-eol)))
1898
1899 (let ((eol-type (coding-system-eol-type new-coding)))
1900 (if (and (numberp new-eol) (vectorp eol-type))
1901 (aref eol-type new-eol)
1902 new-coding)))))))
1903
1904 (defun modify-coding-system-alist (target-type regexp coding-system)
1905 "Modify one of look up tables for finding a coding system on I/O operation.
1906 There are three of such tables, `file-coding-system-alist',
1907 `process-coding-system-alist', and `network-coding-system-alist'.
1908
1909 TARGET-TYPE specifies which of them to modify.
1910 If it is `file', it affects `file-coding-system-alist' (which see).
1911 If it is `process', it affects `process-coding-system-alist' (which see).
1912 If it is `network', it affects `network-coding-system-alist' (which see).
1913
1914 REGEXP is a regular expression matching a target of I/O operation.
1915 The target is a file name if TARGET-TYPE is `file', a program name if
1916 TARGET-TYPE is `process', or a network service name or a port number
1917 to connect to if TARGET-TYPE is `network'.
1918
1919 CODING-SYSTEM is a coding system to perform code conversion on the I/O
1920 operation, or a cons cell (DECODING . ENCODING) specifying the coding systems
1921 for decoding and encoding respectively,
1922 or a function symbol which, when called, returns such a cons cell."
1923 (or (memq target-type '(file process network))
1924 (error "Invalid target type: %s" target-type))
1925 (or (stringp regexp)
1926 (and (eq target-type 'network) (integerp regexp))
1927 (error "Invalid regular expression: %s" regexp))
1928 (if (symbolp coding-system)
1929 (if (not (fboundp coding-system))
1930 (progn
1931 (check-coding-system coding-system)
1932 (setq coding-system (cons coding-system coding-system))))
1933 (check-coding-system (car coding-system))
1934 (check-coding-system (cdr coding-system)))
1935 (cond ((eq target-type 'file)
1936 (let ((slot (assoc regexp file-coding-system-alist)))
1937 (if slot
1938 (setcdr slot coding-system)
1939 (setq file-coding-system-alist
1940 (cons (cons regexp coding-system)
1941 file-coding-system-alist)))))
1942 ((eq target-type 'process)
1943 (let ((slot (assoc regexp process-coding-system-alist)))
1944 (if slot
1945 (setcdr slot coding-system)
1946 (setq process-coding-system-alist
1947 (cons (cons regexp coding-system)
1948 process-coding-system-alist)))))
1949 (t
1950 (let ((slot (assoc regexp network-coding-system-alist)))
1951 (if slot
1952 (setcdr slot coding-system)
1953 (setq network-coding-system-alist
1954 (cons (cons regexp coding-system)
1955 network-coding-system-alist)))))))
1956
1957 (defun decode-coding-inserted-region (from to filename
1958 &optional visit beg end replace)
1959 "Decode the region between FROM and TO as if it is read from file FILENAME.
1960 The idea is that the text between FROM and TO was just inserted somehow.
1961 Optional arguments VISIT, BEG, END, and REPLACE are the same as those
1962 of the function `insert-file-contents'.
1963 Part of the job of this function is setting `buffer-undo-list' appropriately."
1964 (save-excursion
1965 (save-restriction
1966 (let ((coding coding-system-for-read)
1967 undo-list-saved)
1968 (if visit
1969 ;; Temporarily turn off undo recording, if we're decoding the
1970 ;; text of a visited file.
1971 (setq buffer-undo-list t)
1972 ;; Otherwise, if we can recognize the undo elt for the insertion,
1973 ;; remove it and get ready to replace it later.
1974 ;; In the mean time, turn off undo recording.
1975 (let ((last (car-safe buffer-undo-list)))
1976 (if (and (consp last) (eql (car last) from) (eql (cdr last) to))
1977 (setq undo-list-saved (cdr buffer-undo-list)
1978 buffer-undo-list t))))
1979 (narrow-to-region from to)
1980 (goto-char (point-min))
1981 (or coding
1982 (setq coding (funcall set-auto-coding-function
1983 filename (- (point-max) (point-min)))))
1984 (or coding
1985 (setq coding (car (find-operation-coding-system
1986 'insert-file-contents
1987 filename visit beg end replace))))
1988 (if (coding-system-p coding)
1989 (or enable-multibyte-characters
1990 (setq coding
1991 (coding-system-change-text-conversion coding 'raw-text)))
1992 (setq coding nil))
1993 (if coding
1994 (decode-coding-region (point-min) (point-max) coding)
1995 (setq last-coding-system-used coding))
1996 ;; If we're decoding the text of a visited file,
1997 ;; the undo list should start out empty.
1998 (if visit
1999 (setq buffer-undo-list nil)
2000 ;; If we decided to replace the undo entry for the insertion,
2001 ;; do so now.
2002 (if undo-list-saved
2003 (setq buffer-undo-list
2004 (cons (cons from (point-max)) undo-list-saved))))))))
2005
2006 (defun recode-region (start end new-coding coding)
2007 "Re-decode the region (previously decoded by CODING) by NEW-CODING."
2008 (interactive
2009 (list (region-beginning) (region-end)
2010 (read-coding-system "Text was really in: ")
2011 (let ((coding (or buffer-file-coding-system last-coding-system-used)))
2012 (read-coding-system
2013 (concat "But was interpreted as"
2014 (if coding (format " (default %S): " coding) ": "))
2015 coding))))
2016 (or (and new-coding coding)
2017 (error "Coding system not specified"))
2018 ;; Check it before we encode the region.
2019 (check-coding-system new-coding)
2020 (save-restriction
2021 (narrow-to-region start end)
2022 (encode-coding-region (point-min) (point-max) coding)
2023 (decode-coding-region (point-min) (point-max) new-coding)))
2024
2025 (defun make-translation-table (&rest args)
2026 "Make a translation table from arguments.
2027 A translation table is a char table intended for character
2028 translation in CCL programs.
2029
2030 Each argument is a list of elements of the form (FROM . TO), where FROM
2031 is a character to be translated to TO.
2032
2033 FROM can be a generic character (see `make-char'). In this case, TO is
2034 a generic character containing the same number of characters, or an
2035 ordinary character. If FROM and TO are both generic characters, all
2036 characters belonging to FROM are translated to characters belonging to TO
2037 without changing their position code(s).
2038
2039 The arguments and forms in each argument are processed in the given
2040 order, and if a previous form already translates TO to some other
2041 character, say TO-ALT, FROM is also translated to TO-ALT."
2042 (let ((table (make-char-table 'translation-table))
2043 revlist)
2044 (while args
2045 (let ((elts (car args)))
2046 (while elts
2047 (let* ((from (car (car elts)))
2048 (from-i 0) ; degree of freedom of FROM
2049 (from-rev (nreverse (split-char from)))
2050 (to (cdr (car elts)))
2051 (to-i 0) ; degree of freedom of TO
2052 (to-rev (nreverse (split-char to))))
2053 ;; Check numbers of heading 0s in FROM-REV and TO-REV.
2054 (while (eq (car from-rev) 0)
2055 (setq from-i (1+ from-i) from-rev (cdr from-rev)))
2056 (while (eq (car to-rev) 0)
2057 (setq to-i (1+ to-i) to-rev (cdr to-rev)))
2058 (if (and (/= from-i to-i) (/= to-i 0))
2059 (error "Invalid character pair (%d . %d)" from to))
2060 ;; If we have already translated TO to TO-ALT, FROM should
2061 ;; also be translated to TO-ALT. But, this is only if TO
2062 ;; is a generic character or TO-ALT is not a generic
2063 ;; character.
2064 (let ((to-alt (aref table to)))
2065 (if (and to-alt
2066 (or (> to-i 0) (not (generic-char-p to-alt))))
2067 (setq to to-alt)))
2068 (if (> from-i 0)
2069 (set-char-table-default table from to)
2070 (aset table from to))
2071 ;; If we have already translated some chars to FROM, they
2072 ;; should also be translated to TO.
2073 (let ((l (assq from revlist)))
2074 (if l
2075 (let ((ch (car l)))
2076 (setcar l to)
2077 (setq l (cdr l))
2078 (while l
2079 (aset table ch to)
2080 (setq l (cdr l)) ))))
2081 ;; Now update REVLIST.
2082 (let ((l (assq to revlist)))
2083 (if l
2084 (setcdr l (cons from (cdr l)))
2085 (setq revlist (cons (list to from) revlist)))))
2086 (setq elts (cdr elts))))
2087 (setq args (cdr args)))
2088 ;; Return TABLE just created.
2089 table))
2090
2091 (defun make-translation-table-from-vector (vec)
2092 "Make translation table from decoding vector VEC.
2093 VEC is an array of 256 elements to map unibyte codes to multibyte
2094 characters. Elements may be nil for undefined code points.
2095 See also the variable `nonascii-translation-table'."
2096 (let ((table (make-char-table 'translation-table))
2097 (rev-table (make-char-table 'translation-table))
2098 ch)
2099 (dotimes (i 256)
2100 (setq ch (aref vec i))
2101 (when ch
2102 (aset table i ch)
2103 (if (>= ch 256)
2104 (aset rev-table ch i))))
2105 (set-char-table-extra-slot table 0 rev-table)
2106 table))
2107
2108 (defun define-translation-table (symbol &rest args)
2109 "Define SYMBOL as the name of translation table made by ARGS.
2110 This sets up information so that the table can be used for
2111 translations in a CCL program.
2112
2113 If the first element of ARGS is a char-table whose purpose is
2114 `translation-table', just define SYMBOL to name it. (Note that this
2115 function does not bind SYMBOL.)
2116
2117 Any other ARGS should be suitable as arguments of the function
2118 `make-translation-table' (which see).
2119
2120 This function sets properties `translation-table' and
2121 `translation-table-id' of SYMBOL to the created table itself and the
2122 identification number of the table respectively. It also registers
2123 the table in `translation-table-vector'."
2124 (let ((table (if (and (char-table-p (car args))
2125 (eq (char-table-subtype (car args))
2126 'translation-table))
2127 (car args)
2128 (apply 'make-translation-table args)))
2129 (len (length translation-table-vector))
2130 (id 0)
2131 (done nil))
2132 (put symbol 'translation-table table)
2133 (while (not done)
2134 (if (>= id len)
2135 (setq translation-table-vector
2136 (vconcat translation-table-vector (make-vector len nil))))
2137 (let ((slot (aref translation-table-vector id)))
2138 (if (or (not slot)
2139 (eq (car slot) symbol))
2140 (progn
2141 (aset translation-table-vector id (cons symbol table))
2142 (setq done t))
2143 (setq id (1+ id)))))
2144 (put symbol 'translation-table-id id)
2145 id))
2146
2147 (defun translate-region (start end table)
2148 "From START to END, translate characters according to TABLE.
2149 TABLE is a string or a char-table.
2150 If TABLE is a string, the Nth character in it is the mapping
2151 for the character with code N.
2152 If TABLE is a char-table, the element for character N is the mapping
2153 for the character with code N.
2154 It returns the number of characters changed."
2155 (interactive
2156 (list (region-beginning)
2157 (region-end)
2158 (let (table l)
2159 (dotimes (i (length translation-table-vector))
2160 (if (consp (aref translation-table-vector i))
2161 (push (list (symbol-name
2162 (car (aref translation-table-vector i)))) l)))
2163 (if (not l)
2164 (error "No translation table defined"))
2165 (while (not table)
2166 (setq table (completing-read "Translation table: " l nil t)))
2167 (intern table))))
2168 (if (symbolp table)
2169 (let ((val (get table 'translation-table)))
2170 (or (char-table-p val)
2171 (error "Invalid translation table name: %s" table))
2172 (setq table val)))
2173 (translate-region-internal start end table))
2174
2175 (put 'with-category-table 'lisp-indent-function 1)
2176
2177 (defmacro with-category-table (table &rest body)
2178 "Evaluate BODY with category table of current buffer set to TABLE.
2179 The category table of the current buffer is saved, BODY is evaluated,
2180 then the saved table is restored, even in case of an abnormal exit.
2181 Value is what BODY returns."
2182 (let ((old-table (make-symbol "old-table"))
2183 (old-buffer (make-symbol "old-buffer")))
2184 `(let ((,old-table (category-table))
2185 (,old-buffer (current-buffer)))
2186 (unwind-protect
2187 (progn
2188 (set-category-table ,table)
2189 ,@body)
2190 (save-current-buffer
2191 (set-buffer ,old-buffer)
2192 (set-category-table ,old-table))))))
2193
2194 (defun define-translation-hash-table (symbol table)
2195 "Define SYMBOL as the name of the hash translation TABLE for use in CCL.
2196
2197 Analogous to `define-translation-table', but updates
2198 `translation-hash-table-vector' and the table is for use in the CCL
2199 `lookup-integer' and `lookup-character' functions."
2200 (unless (and (symbolp symbol)
2201 (hash-table-p table))
2202 (error "Bad args to define-translation-hash-table"))
2203 (let ((len (length translation-hash-table-vector))
2204 (id 0)
2205 done)
2206 (put symbol 'translation-hash-table table)
2207 (while (not done)
2208 (if (>= id len)
2209 (setq translation-hash-table-vector
2210 (vconcat translation-hash-table-vector [nil])))
2211 (let ((slot (aref translation-hash-table-vector id)))
2212 (if (or (not slot)
2213 (eq (car slot) symbol))
2214 (progn
2215 (aset translation-hash-table-vector id (cons symbol table))
2216 (setq done t))
2217 (setq id (1+ id)))))
2218 (put symbol 'translation-hash-table-id id)
2219 id))
2220
2221 ;;; Initialize some variables.
2222
2223 (put 'use-default-ascent 'char-table-extra-slots 0)
2224 (setq use-default-ascent (make-char-table 'use-default-ascent))
2225 (put 'ignore-relative-composition 'char-table-extra-slots 0)
2226 (setq ignore-relative-composition
2227 (make-char-table 'ignore-relative-composition))
2228
2229
2230 ;;; Built-in auto-coding-functions:
2231
2232 (defun sgml-xml-auto-coding-function (size)
2233 "Determine whether the buffer is XML, and if so, its encoding.
2234 This function is intended to be added to `auto-coding-functions'."
2235 (setq size (+ (point) size))
2236 (when (re-search-forward "\\`[[:space:]\n]*<\\?xml" size t)
2237 (let ((end (save-excursion
2238 ;; This is a hack.
2239 (re-search-forward "[\"']\\s-*\\?>" size t))))
2240 (when end
2241 (if (re-search-forward "encoding=[\"']\\(.+?\\)[\"']" end t)
2242 (let* ((match (match-string 1))
2243 (sym (intern (downcase match))))
2244 (if (coding-system-p sym)
2245 sym
2246 (message "Warning: unknown coding system \"%s\"" match)
2247 nil))
2248 'utf-8)))))
2249
2250 (defun sgml-html-meta-auto-coding-function (size)
2251 "If the buffer has an HTML meta tag, use it to determine encoding.
2252 This function is intended to be added to `auto-coding-functions'."
2253 (setq size (min (+ (point) size)
2254 ;; Only search forward 10 lines
2255 (save-excursion
2256 (forward-line 10)
2257 (point))))
2258 (when (and (search-forward "<html" size t)
2259 (re-search-forward "<meta\\s-+http-equiv=\"content-type\"\\s-+content=\"text/\\sw+;\\s-*charset=\\(.+?\\)\"" size t))
2260 (let* ((match (match-string 1))
2261 (sym (intern (downcase match))))
2262 (if (coding-system-p sym)
2263 sym
2264 (message "Warning: unknown coding system \"%s\"" match)
2265 nil))))
2266
2267 ;;;
2268 (provide 'mule)
2269
2270 ;;; arch-tag: 9aebaa6e-0e8a-40a9-b857-cb5d04a39e7c
2271 ;;; mule.el ends here