;;; flow-fill.el --- interprete RFC2646 "flowed" text
-;; Copyright (C) 2000 Free Software Foundation, Inc.
+
+;; Copyright (C) 2000, 2001, 2002 Free Software Foundation, Inc.
;; Author: Simon Josefsson <jas@pdc.kth.se>
;; Keywords: mail
-;; This program is free software; you can redistribute it and/or modify
+;; 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 of the License, or
-;; (at your option) any later version.
-;;
-;; This program is distributed in the hope that it will be useful,
+;; 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 this program; if not, write to the Free Software
-;; Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+;; along with GNU Emacs; see the file COPYING. If not, write to the
+;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
;;; Commentary:
;; paragraph and we let `fill-region' fill the long line into several
;; lines with the quote prefix as `fill-prefix'.
-;; Todo: encoding
+;; Todo: implement basic `fill-region' (Emacs and XEmacs
+;; implementations differ..)
-;; History:
+;;; History:
;; 2000-02-17 posted on ding mailing list
;; 2000-02-19 use `point-at-{b,e}ol' in XEmacs
;; 2000-03-11 no compile warnings for point-at-bol stuff
-;; 2000-03-26 commited to gnus cvs
+;; 2000-03-26 committed to gnus cvs
+;; 2000-10-23 don't flow "-- " lines, make "quote-depth wins" rule
+;; work when first line is at level 0.
+;; 2002-01-12 probably incomplete encoding support
;;; Code:
+(eval-when-compile (require 'cl))
+
+(defcustom fill-flowed-display-column 'fill-column
+ "Column beyond which format=flowed lines are wrapped, when displayed.
+This can be a lisp expression or an integer."
+ :type '(choice (const :tag "Standard `fill-column'" fill-column)
+ (const :tag "Fit Window" (- (window-width) 5))
+ (sexp)
+ (integer)))
+
+(defcustom fill-flowed-encode-column 66
+ "Column beyond which format=flowed lines are wrapped, in outgoing messages.
+This can be a lisp expression or an integer.
+RFC 2646 suggests 66 characters for readability."
+ :type '(choice (const :tag "Standard fill-column" fill-column)
+ (const :tag "RFC 2646 default (66)" 66)
+ (sexp)
+ (integer)))
+
(eval-and-compile
- (fset 'fill-flowed-point-at-bol
+ (defalias 'fill-flowed-point-at-bol
(if (fboundp 'point-at-bol)
'point-at-bol
'line-beginning-position))
-
- (fset 'fill-flowed-point-at-eol
+
+ (defalias 'fill-flowed-point-at-eol
(if (fboundp 'point-at-eol)
'point-at-eol
'line-end-position)))
+(defun fill-flowed-encode (&optional buffer)
+ (with-current-buffer (or buffer (current-buffer))
+ ;; No point in doing this unless hard newlines is used.
+ (when use-hard-newlines
+ (let ((start (point-min)) end)
+ ;; Go through each paragraph, filling it and adding SPC
+ ;; as the last character on each line.
+ (while (setq end (text-property-any start (point-max) 'hard 't))
+ (let ((fill-column (eval fill-flowed-encode-column)))
+ (fill-region start end t 'nosqueeze 'to-eop))
+ (goto-char start)
+ ;; `fill-region' probably distorted end.
+ (setq end (text-property-any start (point-max) 'hard 't))
+ (while (and (< (point) end)
+ (re-search-forward "$" (1- end) t))
+ (insert " ")
+ (setq end (1+ end))
+ (forward-char))
+ (goto-char (setq start (1+ end)))))
+ t)))
+
(defun fill-flowed (&optional buffer)
(save-excursion
(set-buffer (or (current-buffer) buffer))
(when (save-excursion
(beginning-of-line)
(looking-at "^\\(>*\\)\\( ?\\)"))
- (let ((quote (match-string 1)))
+ (let ((quote (match-string 1))
+ sig)
(if (string= quote "")
(setq quote nil))
(when (and quote (string= (match-string 2) ""))
(beginning-of-line)
(when (> (skip-chars-forward ">") 0)
(insert " "))))
+ ;; XXX slightly buggy handling of "-- "
(while (and (save-excursion
- (backward-char 3)
+ (ignore-errors (backward-char 3))
+ (setq sig (looking-at "-- "))
(looking-at "[^-][^-] "))
(save-excursion
(unless (eobp)
(forward-char 1)
- (if quote
- (looking-at (format "^\\(%s\\)\\([^>]\\)" quote))
- (looking-at "^ ?")))))
+ (looking-at (format "^\\(%s\\)\\([^>]\\)"
+ (or quote " ?"))))))
(save-excursion
(replace-match (if (string= (match-string 2) " ")
"" "\\2")))
(backward-delete-char -1)
(end-of-line))
- (let ((fill-prefix (when quote (concat quote " "))))
- (fill-region (fill-flowed-point-at-bol)
- (fill-flowed-point-at-eol)
- 'left 'nosqueeze)))))))
+ (unless sig
+ (condition-case nil
+ (let ((fill-prefix (when quote (concat quote " ")))
+ (fill-column (eval fill-flowed-display-column))
+ filladapt-mode)
+ (fill-region (fill-flowed-point-at-bol)
+ (min (1+ (fill-flowed-point-at-eol))
+ (point-max))
+ 'left 'nosqueeze))
+ (error
+ (forward-line 1)
+ nil))))))))
(provide 'flow-fill)