[bpt/emacs.git] / lisp / international / latexenc.el

;;; latexenc.el --- guess correct coding system in LaTeX files -*-coding: iso-2022-7bit -*-

;; Copyright (C) 2005, 2006 Free Software Foundation, Inc.

;; Author: Arne J\e,Ax\e(Brgensen <arne@arnested.dk>
;; Keywords: mule, coding system, latex

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to the
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.

;;; Commentary:

;; This code tries to guess the correct coding system of a LaTeX file.

;; First it searches for a \inputencoding{...} or
;; \usepackage[...]{inputenc} line in the file and looks up the ... in
;; `latex-inputenc-coding-alist' to find the corresponding coding
;; system.

;; If this fails it will search for AUCTeX's TeX-master or tex-mode's
;; tex-main-file variable in the local variables section and visit
;; that file to get the coding system from the master file. This check
;; can be disabled by setting `latexenc-dont-use-TeX-master-flag' to
;; t.

;; If we have still not found a coding system we will try to use the
;; standard tex-mode's `tex-guess-main-file' and get the coding system
;; from the main file. This check can be disabled by setting
;; `latexenc-dont-use-tex-guess-main-file-flag' to t.

;; The functionality is enabled by adding the function
;; `latexenc-find-file-coding-system' to `file-coding-system-alist'
;; like this

;; (add-to-list 'file-coding-system-alist
;; 	     '("\\.\\(tex\\|ltx\\|dtx\\|drv\\)\\'" . latexenc-find-file-coding-system))

;;; Code:

;;;###autoload
(defcustom latex-inputenc-coding-alist
  '(("ansinew" . windows-1252) ; MS Windows ANSI encoding, extension of Latin-1
    ("applemac" . mac-roman)
    ("ascii" . us-ascii)
    ("cp1250" . windows-1250) ; MS Windows encoding, codepage 1250
    ("cp1252" . windows-1252) ; synonym of ansinew
    ("cp1257" . cp1257)
    ("cp437de" . cp437) ; IBM code page 437 (German version): 225 is \ss
    ("cp437" . cp437) ; IBM code page 437: 225 is \beta
    ("cp850" . cp850) ; IBM code page 850
    ("cp852" . cp852) ; IBM code page 852
    ;; ("cp858" . undecided) ; IBM code page 850 but with a euro symbol
    ("cp865" . cp865) ; IBM code page 865
    ;; The DECMultinational charaterset used by the OpenVMS system
    ;; ("decmulti" . undecided)
    ("latin1" . iso-8859-1)
    ("latin2" . iso-8859-2)
    ("latin3" . iso-8859-3)
    ("latin4" . iso-8859-4)
    ("latin5" . iso-8859-5)
    ("latin9" . iso-8859-15)
    ;; ("latin10" . undecided)
    ;; ("macce" . undecided) ; Apple Central European
    ("next" . next) ; The Next encoding
    ("utf8" . utf-8)
    ("utf8x" . utf-8)) ; used by the Unicode LaTeX package
  "Mapping from LaTeX encodings in \"inputenc.sty\" to Emacs coding systems.
LaTeX encodings are specified with \"\\usepackage[encoding]{inputenc}\".
Used by the function `latexenc-find-file-coding-system'."
  :group 'files
  :group 'mule
  :type '(alist :key-type (string :tag "LaTeX input encoding")
		:value-type (coding-system :tag "Coding system")))

;;;###autoload
(defun latexenc-inputenc-to-coding-system (inputenc)
  "Return the corresponding coding-system for the specified input encoding.
Return nil if no matching coding system can be found."
  (cdr (assoc inputenc latex-inputenc-coding-alist)))

;;;###autoload
(defun latexenc-coding-system-to-inputenc (cs)
  "Return the corresponding input encoding for the specified coding system.
Return nil if no matching input encoding can be found."
  (let (result)
    (catch 'result
      (dolist (elem latex-inputenc-coding-alist result)
	(let ((elem-cs (cdr elem)))
	  (when (and (coding-system-p elem-cs)
		     (coding-system-p cs)
		     (eq (coding-system-base cs) (coding-system-base elem-cs)))
	    (setq result (car elem))
	    (throw 'result result)))))))

(defvar latexenc-dont-use-TeX-master-flag nil
  "Non-nil means don't follow TeX-master to find the coding system.")

(defvar latexenc-dont-use-tex-guess-main-file-flag nil
  "Non-nil means don't use tex-guessmain-file to find the coding system.")

;;;###autoload
(defun latexenc-find-file-coding-system (arg-list)
  "Determine the coding system of a LaTeX file if it uses \"inputenc.sty\".
The mapping from LaTeX's \"inputenc.sty\" encoding names to Emacs
coding system names is determined from `latex-inputenc-coding-alist'."
  (if (eq (car arg-list) 'insert-file-contents)
      (save-excursion
        ;; try to find the coding system in this file
        (goto-char (point-min))
	(if (catch 'cs
	      (let ((case-fold-search nil))
		(while (search-forward "inputenc" nil t)
		  (goto-char (match-beginning 0))
		  (beginning-of-line)
		  (if (or (looking-at "[^%\n]*\\\\usepackage\\[\\([^]]*\\)\\]{\\([^}]*,\\)?inputenc\\(,[^}]*\\)?}")
			  (looking-at "[^%\n]*\\\\inputencoding{\\([^}]*\\)}"))
		      (throw 'cs t)
		    (goto-char (match-end 0))))))
	    (let* ((match (match-string 1))
		   (sym (or (latexenc-inputenc-to-coding-system match)
                            (intern match))))
	      (cond
               ((coding-system-p sym) sym)
               ((and (require 'code-pages nil t) (coding-system-p sym)) sym)
               (t 'undecided)))
          ;; else try to find it in the master/main file

	  ;; Fixme: If the current file is in an archive (e.g. tar,
	  ;; zip), we should find the master file in that archive.
	  ;; But, that is not yet implemented.   -- K.Handa
          (let ((default-directory (if (stringp (nth 1 arg-list))
				       (file-name-directory (nth 1 arg-list))
				     default-directory))
		latexenc-main-file)
            ;; Is there a TeX-master or tex-main-file in the local variables
            ;; section?
            (unless latexenc-dont-use-TeX-master-flag
              (goto-char (point-max))
	      (search-backward "\n\^L" (max (- (point-max) 3000) (point-min))
                               'move)
	      (search-forward "Local Variables:" nil t)
              (when (re-search-forward
                     "^%+ *\\(TeX-master\\|tex-main-file\\): *\"\\(.+\\)\""
                     nil t)
                (let ((file (match-string 2)))
                  (dolist (ext `("" ,(if (boundp 'TeX-default-extension)
                                         (concat "." TeX-default-extension)
                                       "")
                                 ".tex" ".ltx" ".dtx" ".drv"))
                    (if (and (null latexenc-main-file) ;Stop at first.
                             (file-exists-p (concat file ext)))
                        (setq latexenc-main-file (concat file ext)))))))
            ;; try tex-modes tex-guess-main-file
            (when (and (not latexenc-dont-use-tex-guess-main-file-flag)
                       (not latexenc-main-file))
              ;; Use a separate `when' so the byte-compiler sees the fboundp.
              (when (fboundp 'tex-guess-main-file)
                (let ((tex-start-of-header "\\\\document\\(style\\|class\\)"))
                  (setq latexenc-main-file (tex-guess-main-file)))))
            ;; if we found a master/main file get the coding system from it
            (if (and latexenc-main-file
                     (file-regular-p latexenc-main-file)
                     (file-readable-p latexenc-main-file))
                (let* ((latexenc-dont-use-tex-guess-main-file-flag t)
                       (latexenc-dont-use-TeX-master-flag t)
                       (latexenc-main-buffer
                        (find-file-noselect latexenc-main-file t)))
                  (coding-system-base   ;Disregard the EOL part of the CS.
                   (with-current-buffer latexenc-main-buffer
                     (or coding-system-for-write buffer-file-coding-system))))
              'undecided))))
    'undecided))

\f
(provide 'latexenc)

;; arch-tag: f971bc3e-1fec-4609-8f2f-73dd41ab22e1
;;; latexenc.el ends here
Commit	Line	Data
c80977a1	1	;;; latexenc.el --- guess correct coding system in LaTeX files --coding: iso-2022-7bit --
18acc655	2
e450a16a	3	;; Copyright (C) 2005, 2006 Free Software Foundation, Inc.
18acc655 TTN	4
	5	;; Author: Arne J\e,Ax\e(Brgensen <arne@arnested.dk>
	6	;; Keywords: mule, coding system, latex
	7
	8	;; This file is part of GNU Emacs.
	9
	10	;; GNU Emacs is free software; you can redistribute it and/or modify
	11	;; it under the terms of the GNU General Public License as published by
	12	;; the Free Software Foundation; either version 2, or (at your option)
	13	;; any later version.
	14
	15	;; GNU Emacs is distributed in the hope that it will be useful,
	16	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	17	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	18	;; GNU General Public License for more details.
	19
	20	;; You should have received a copy of the GNU General Public License
	21	;; along with GNU Emacs; see the file COPYING. If not, write to the
3a35cf56 LK	22	;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
3a35cf56 LK	23	;; Boston, MA 02110-1301, USA.
18acc655 TTN	24
	25	;;; Commentary:
	26
	27	;; This code tries to guess the correct coding system of a LaTeX file.
	28
	29	;; First it searches for a \inputencoding{...} or
	30	;; \usepackage[...]{inputenc} line in the file and looks up the ... in
	31	;; `latex-inputenc-coding-alist' to find the corresponding coding
	32	;; system.
	33
	34	;; If this fails it will search for AUCTeX's TeX-master or tex-mode's
	35	;; tex-main-file variable in the local variables section and visit
	36	;; that file to get the coding system from the master file. This check
	37	;; can be disabled by setting `latexenc-dont-use-TeX-master-flag' to
	38	;; t.
	39
	40	;; If we have still not found a coding system we will try to use the
	41	;; standard tex-mode's `tex-guess-main-file' and get the coding system
	42	;; from the main file. This check can be disabled by setting
	43	;; `latexenc-dont-use-tex-guess-main-file-flag' to t.
	44
	45	;; The functionality is enabled by adding the function
	46	;; `latexenc-find-file-coding-system' to `file-coding-system-alist'
	47	;; like this
	48
	49	;; (add-to-list 'file-coding-system-alist
a15d6d35	50	;; '("\\.\\(tex\\\|ltx\\\|dtx\\\|drv\\)\\'" . latexenc-find-file-coding-system))
18acc655 TTN	51
	52	;;; Code:
	53
	54	;;;###autoload
	55	(defcustom latex-inputenc-coding-alist
	56	'(("ansinew" . windows-1252) ; MS Windows ANSI encoding, extension of Latin-1
	57	("applemac" . mac-roman)
	58	("ascii" . us-ascii)
	59	("cp1250" . windows-1250) ; MS Windows encoding, codepage 1250
	60	("cp1252" . windows-1252) ; synonym of ansinew
	61	("cp1257" . cp1257)
	62	("cp437de" . cp437) ; IBM code page 437 (German version): 225 is \ss
	63	("cp437" . cp437) ; IBM code page 437: 225 is \beta
	64	("cp850" . cp850) ; IBM code page 850
	65	("cp852" . cp852) ; IBM code page 852
	66	;; ("cp858" . undecided) ; IBM code page 850 but with a euro symbol
	67	("cp865" . cp865) ; IBM code page 865
	68	;; The DECMultinational charaterset used by the OpenVMS system
	69	;; ("decmulti" . undecided)
	70	("latin1" . iso-8859-1)
	71	("latin2" . iso-8859-2)
	72	("latin3" . iso-8859-3)
	73	("latin4" . iso-8859-4)
	74	("latin5" . iso-8859-5)
	75	("latin9" . iso-8859-15)
	76	;; ("latin10" . undecided)
	77	;; ("macce" . undecided) ; Apple Central European
	78	("next" . next) ; The Next encoding
	79	("utf8" . utf-8)
	80	("utf8x" . utf-8)) ; used by the Unicode LaTeX package
eac5c1f6	81	"Mapping from LaTeX encodings in \"inputenc.sty\" to Emacs coding systems.
06e2cc3d	82	LaTeX encodings are specified with \"\\usepackage[encoding]{inputenc}\".
18acc655 TTN	83	Used by the function `latexenc-find-file-coding-system'."
	84	:group 'files
	85	:group 'mule
	86	:type '(alist :key-type (string :tag "LaTeX input encoding")
	87	:value-type (coding-system :tag "Coding system")))
	88
	89	;;;###autoload
	90	(defun latexenc-inputenc-to-coding-system (inputenc)
	91	"Return the corresponding coding-system for the specified input encoding.
	92	Return nil if no matching coding system can be found."
	93	(cdr (assoc inputenc latex-inputenc-coding-alist)))
	94
	95	;;;###autoload
	96	(defun latexenc-coding-system-to-inputenc (cs)
	97	"Return the corresponding input encoding for the specified coding system.
	98	Return nil if no matching input encoding can be found."
	99	(let (result)
	100	(catch 'result
	101	(dolist (elem latex-inputenc-coding-alist result)
	102	(let ((elem-cs (cdr elem)))
	103	(when (and (coding-system-p elem-cs)
	104	(coding-system-p cs)
	105	(eq (coding-system-base cs) (coding-system-base elem-cs)))
	106	(setq result (car elem))
	107	(throw 'result result)))))))
	108
	109	(defvar latexenc-dont-use-TeX-master-flag nil
	110	"Non-nil means don't follow TeX-master to find the coding system.")
	111
	112	(defvar latexenc-dont-use-tex-guess-main-file-flag nil
	113	"Non-nil means don't use tex-guessmain-file to find the coding system.")
	114
	115	;;;###autoload
	116	(defun latexenc-find-file-coding-system (arg-list)
	117	"Determine the coding system of a LaTeX file if it uses \"inputenc.sty\".
	118	The mapping from LaTeX's \"inputenc.sty\" encoding names to Emacs
	119	coding system names is determined from `latex-inputenc-coding-alist'."
	120	(if (eq (car arg-list) 'insert-file-contents)
	121	(save-excursion
	122	;; try to find the coding system in this file
	123	(goto-char (point-min))
4b0fcb5d LK	124	(if (catch 'cs
	125	(let ((case-fold-search nil))
	126	(while (search-forward "inputenc" nil t)
	127	(goto-char (match-beginning 0))
	128	(beginning-of-line)
	129	(if (or (looking-at "[^%\n]\\\\usepackage\\[\\([^]]\\)\\]{\\([^}],\\)?inputenc\\(,[^}]\\)?}")
	130	(looking-at "[^%\n]\\\\inputencoding{\\([^}]\\)}"))
	131	(throw 'cs t)
	132	(goto-char (match-end 0))))))
	133	(let* ((match (match-string 1))
14cb9d7b SM	134	(sym (or (latexenc-inputenc-to-coding-system match)
	135	(intern match))))
	136	(cond
	137	((coding-system-p sym) sym)
	138	((and (require 'code-pages nil t) (coding-system-p sym)) sym)
	139	(t 'undecided)))
18acc655	140	;; else try to find it in the master/main file
dccee2cb KH	141
	142	;; Fixme: If the current file is in an archive (e.g. tar,
	143	;; zip), we should find the master file in that archive.
	144	;; But, that is not yet implemented. -- K.Handa
	145	(let ((default-directory (if (stringp (nth 1 arg-list))
	146	(file-name-directory (nth 1 arg-list))
	147	default-directory))
	148	latexenc-main-file)
14cb9d7b SM	149	;; Is there a TeX-master or tex-main-file in the local variables
14cb9d7b SM	150	;; section?
18acc655 TTN	151	(unless latexenc-dont-use-TeX-master-flag
18acc655 TTN	152	(goto-char (point-max))
14cb9d7b SM	153	(search-backward "\n\^L" (max (- (point-max) 3000) (point-min))
14cb9d7b SM	154	'move)
4b0fcb5d	155	(search-forward "Local Variables:" nil t)
14cb9d7b SM	156	(when (re-search-forward
	157	"^%+ \\(TeX-master\\\|tex-main-file\\): \"\\(.+\\)\""
	158	nil t)
	159	(let ((file (match-string 2)))
	160	(dolist (ext `("" ,(if (boundp 'TeX-default-extension)
	161	(concat "." TeX-default-extension)
	162	"")
	163	".tex" ".ltx" ".dtx" ".drv"))
	164	(if (and (null latexenc-main-file) ;Stop at first.
a15df48e	165	(file-exists-p (concat file ext)))
14cb9d7b	166	(setq latexenc-main-file (concat file ext)))))))
18acc655 TTN	167	;; try tex-modes tex-guess-main-file
18acc655 TTN	168	(when (and (not latexenc-dont-use-tex-guess-main-file-flag)
ed975fa6 SM	169	(not latexenc-main-file))
	170	;; Use a separate `when' so the byte-compiler sees the fboundp.
	171	(when (fboundp 'tex-guess-main-file)
	172	(let ((tex-start-of-header "\\\\document\\(style\\\|class\\)"))
	173	(setq latexenc-main-file (tex-guess-main-file)))))
18acc655 TTN	174	;; if we found a master/main file get the coding system from it
18acc655 TTN	175	(if (and latexenc-main-file
96a6ec17	176	(file-regular-p latexenc-main-file)
18acc655 TTN	177	(file-readable-p latexenc-main-file))
	178	(let* ((latexenc-dont-use-tex-guess-main-file-flag t)
	179	(latexenc-dont-use-TeX-master-flag t)
14cb9d7b SM	180	(latexenc-main-buffer
	181	(find-file-noselect latexenc-main-file t)))
	182	(coding-system-base ;Disregard the EOL part of the CS.
	183	(with-current-buffer latexenc-main-buffer
	184	(or coding-system-for-write buffer-file-coding-system))))
18acc655 TTN	185	'undecided))))
	186	'undecided))
	187
cc211a0f	188	\f
18acc655 TTN	189	(provide 'latexenc)
18acc655 TTN	190
2183c76d	191	;; arch-tag: f971bc3e-1fec-4609-8f2f-73dd41ab22e1
18acc655	192	;;; latexenc.el ends here