;;; rfc2047.el --- functions for encoding and decoding rfc2047 messages
-;; Copyright (C) 1998, 1999, 2000, 2002, 2003 Free Software Foundation, Inc.
+
+;; Copyright (C) 1998, 1999, 2000, 2002, 2003, 2004
+;; Free Software Foundation, Inc.
;; Author: Lars Magne Ingebrigtsen <larsi@gnus.org>
;; MORIOKA Tomohiko <morioka@jaist.ac.jp>
(require 'base64)
(autoload 'mm-body-7-or-8 "mm-bodies")
-;; Avoid gnus-util for mm- code.
-(defalias 'rfc2047-point-at-bol
- (if (fboundp 'point-at-bol)
- 'point-at-bol
- 'line-beginning-position))
-
-(defalias 'rfc2047-point-at-eol
- (if (fboundp 'point-at-eol)
- 'point-at-eol
- 'line-end-position))
-
(defvar rfc2047-header-encoding-alist
'(("Newsgroups" . nil)
("Followup-To" . nil)
("Message-ID" . nil)
- ("\\(Resent-\\)?\\(From\\|Cc\\|To\\|Bcc\\|Reply-To\\|Sender\\)" .
- address-mime)
+ ("\\(Resent-\\)?\\(From\\|Cc\\|To\\|Bcc\\|Reply-To\\|Sender\
+\\|Mail-Followup-To\\|Mail-Copies-To\\|Approved\\)" . address-mime)
(t . mime))
"*Header/encoding method alist.
The list is traversed sequentially. The keys can either be
(cn-gb-2312 . B)
(euc-kr . B)
(iso-2022-jp-2 . B)
- (iso-2022-int-1 . B))
+ (iso-2022-int-1 . B)
+ (viscii . Q))
"Alist of MIME charsets to RFC2047 encodings.
Valid encodings are nil, `Q' and `B'. These indicate binary (no) encoding,
quoted-printable and base64 respectively.")
-(defvar rfc2047-encoding-function-alist
- '((Q . rfc2047-q-encode-region)
- (B . rfc2047-b-encode-region)
- (nil . ignore))
+(defvar rfc2047-encode-function-alist
+ '((Q . rfc2047-q-encode-string)
+ (B . rfc2047-b-encode-string)
+ (nil . identity))
"Alist of RFC2047 encodings to encoding functions.")
-(defvar rfc2047-q-encoding-alist
- '(("\\(Resent-\\)?\\(From\\|Cc\\|To\\|Bcc\\|Reply-To\\|Sender\\):"
- . "-A-Za-z0-9!*+/" )
- ;; = (\075), _ (\137), ? (\077) are used in the encoded word.
- ;; Avoid using 8bit characters.
- ;; Equivalent to "^\000-\007\011\013\015-\037\200-\377=_?"
- ("." . "\010\012\014\040-\074\076\100-\136\140-\177"))
- "Alist of header regexps and valid Q characters.")
+(defvar rfc2047-encode-encoded-words t
+ "Whether encoded words should be encoded again.")
;;;
;;; Functions for encoding RFC2047 messages
;;;
+(defun rfc2047-qp-or-base64 ()
+ "Return the type with which to encode the buffer.
+This is either `base64' or `quoted-printable'."
+ (save-excursion
+ (let ((limit (min (point-max) (+ 2000 (point-min))))
+ (n8bit 0))
+ (goto-char (point-min))
+ (skip-chars-forward "\x20-\x7f\r\n\t" limit)
+ (while (< (point) limit)
+ (incf n8bit)
+ (forward-char 1)
+ (skip-chars-forward "\x20-\x7f\r\n\t" limit))
+ (if (or (< (* 6 n8bit) (- limit (point-min)))
+ ;; Don't base64, say, a short line with a single
+ ;; non-ASCII char when splitting parts by charset.
+ (= n8bit 1))
+ 'quoted-printable
+ 'base64))))
+
(defun rfc2047-narrow-to-field ()
"Narrow the buffer to the header on the current line."
(beginning-of-line)
(progn
(forward-line 1)
(if (re-search-forward "^[^ \n\t]" nil t)
- (progn
- (beginning-of-line)
- (point))
+ (point-at-bol)
(point-max))))
(goto-char (point-min)))
(save-restriction
(rfc2047-narrow-to-field)
(re-search-forward ":[ \t\n]*" nil t)
- (buffer-substring (point) (point-max)))))
+ (buffer-substring-no-properties (point) (point-max)))))
(defvar rfc2047-encoding-type 'address-mime
"The type of encoding done by `rfc2047-encode-region'.
((eq method 'address-mime)
(rfc2047-encode-region (point) (point-max)))
((eq method 'mime)
- (let (rfc2047-encoding-type)
+ (let ((rfc2047-encoding-type 'mime))
(rfc2047-encode-region (point) (point-max))))
((eq method 'default)
(if (and (featurep 'mule)
(require 'message) ; for message-posting-charset
(let ((charsets
(mm-find-mime-charset-region (point-min) (point-max))))
- (and charsets (not (equal charsets (list message-posting-charset))))))
+ (goto-char (point-min))
+ (or (and rfc2047-encode-encoded-words
+ (search-forward "=?" nil t))
+ (and charsets
+ (not (equal charsets (list (car message-posting-charset))))))))
;; Use this syntax table when parsing into regions that may need
;; encoding. Double quotes are string delimiters, backslash is
;; skip to the end of regions appropriately. Nb. ietf-drums does
;; things differently.
(defconst rfc2047-syntax-table
- (let ((table (make-char-table 'syntax-table '(2))))
+ ;; (make-char-table 'syntax-table '(2)) only works in Emacs.
+ (let ((table (make-syntax-table)))
+ ;; The following is done to work for setting all elements of the table
+ ;; in Emacs 21 and 22 and XEmacs; it appears to be the cleanest way.
+ ;; Play safe and don't assume the form of the word syntax entry --
+ ;; copy it from ?a.
+ (if (fboundp 'set-char-table-range) ; Emacs
+ (funcall (intern "set-char-table-range")
+ table t (aref (standard-syntax-table) ?a))
+ (if (fboundp 'put-char-table)
+ (if (fboundp 'get-char-table) ; warning avoidance
+ (put-char-table t (get-char-table ?a (standard-syntax-table))
+ table))))
(modify-syntax-entry ?\\ "\\" table)
(modify-syntax-entry ?\" "\"" table)
(modify-syntax-entry ?\( "." table)
Dynamically bind `rfc2047-encoding-type' to change that."
(save-restriction
(narrow-to-region b e)
- (if (eq 'mime rfc2047-encoding-type)
- ;; Simple case -- treat as single word.
- (progn
- (goto-char (point-min))
- ;; Does it need encoding?
- (skip-chars-forward "\000-\177" e)
- (unless (eobp)
- (rfc2047-encode b e)))
- ;; `address-mime' case -- take care of quoted words, comments.
- (with-syntax-table rfc2047-syntax-table
- (let ((start) ; start of current token
- end ; end of current token
- ;; Whether there's an encoded word before the current
- ;; token, either immediately or separated by space.
- last-encoded)
+ (let ((encodable-regexp (if rfc2047-encode-encoded-words
+ "[^\000-\177]\\|=\\?"
+ "[^\000-\177]"))
+ start ; start of current token
+ end ; end of current token
+ ;; Whether there's an encoded word before the current token,
+ ;; either immediately or separated by space.
+ last-encoded)
+ (if (eq 'mime rfc2047-encoding-type)
+ ;; Simple case. Continuous words in which all those contain
+ ;; non-ASCII characters are encoded collectively. Encoding
+ ;; ASCII words, including `Re:' used in Subject headers, is
+ ;; avoided for interoperability with non-MIME clients and
+ ;; for making it easy to find keywords.
+ (progn
+ (goto-char (point-min))
+ (while (progn (skip-chars-forward " \t\n")
+ (not (eobp)))
+ (setq start (point))
+ (while (and (looking-at "[ \t\n]*\\([^ \t\n]+\\)")
+ (progn
+ (setq end (match-end 0))
+ (re-search-forward encodable-regexp end t)))
+ (goto-char end))
+ (if (> (point) start)
+ (rfc2047-encode start (point))
+ (goto-char end))))
+ ;; `address-mime' case -- take care of quoted words, comments.
+ (with-syntax-table rfc2047-syntax-table
(goto-char (point-min))
- (condition-case nil ; in case of unbalanced quotes
+ (condition-case nil ; in case of unbalanced quotes
;; Look for rfc2822-style: sequences of atoms, quoted
;; strings, specials, whitespace. (Specials mustn't be
;; encoded.)
(while (not (eobp))
- (setq start (point))
;; Skip whitespace.
- (unless (= 0 (skip-chars-forward " \t"))
- (setq start (point)))
+ (skip-chars-forward " \t\n")
+ (setq start (point))
(cond
((not (char-after))) ; eob
;; else token start
(setq last-encoded nil))
(t ; normal token/whitespace sequence
;; Find the end.
- (forward-word 1)
- (skip-chars-backward " \t")
- (setq end (point))
- ;; Deal with encoding and leading space as for
- ;; quoted words.
- (goto-char start)
- (skip-chars-forward "\000-\177" end)
- (if (= end (point))
- (setq last-encoded nil)
- (when last-encoded
- (goto-char start)
- (skip-chars-backward " \t")
- (insert ? )
- (setq start (point)
- end (1+ end)))
- (rfc2047-encode start end)
- (setq last-encoded t)))))
- (error (error "Invalid data for rfc2047 encoding: %s"
- (buffer-substring b e)))))))
+ (skip-chars-backward " \t\n")
+ (if (and (eq (char-before) ?\()
+ ;; Look for the end of parentheses.
+ (let ((string (buffer-substring (point)
+ (point-max)))
+ (default-major-mode 'fundamental-mode))
+ ;; Use `standard-syntax-table'.
+ (with-temp-buffer
+ (insert "(" string)
+ (goto-char (point-min))
+ (condition-case nil
+ (progn
+ (forward-list 1)
+ (setq end (- (point) 3)))
+ (error nil)))))
+ ;; Encode text as an unstructured field.
+ (let ((rfc2047-encoding-type 'mime))
+ (rfc2047-encode-region start (+ (point) end))
+ (forward-char))
+ ;; Skip one ASCII word, or encode continuous words
+ ;; in which all those contain non-ASCII characters.
+ (skip-chars-forward " \t\n")
+ (setq end nil)
+ (while (not end)
+ (when (looking-at "[\000-\177]+")
+ (setq end (match-end 0))
+ (if (re-search-forward "[ \t\n]\\|\\Sw" end t)
+ (goto-char (match-beginning 0))
+ (goto-char end)
+ (setq end nil)))
+ (unless end
+ (setq end t)
+ (when (looking-at "[^\000-\177]+")
+ (goto-char (match-end 0))
+ (while (and (looking-at "[ \t\n]+\\([^ \t\n]+\\)")
+ (setq end (match-end 0))
+ (string-match "[^\000-\177]"
+ (match-string 1)))
+ (goto-char end))
+ (when (looking-at "[^ \t\n]+")
+ (setq end (match-end 0))
+ (if (re-search-forward "\\Sw+" end t)
+ ;; There are special characters better
+ ;; to be encoded so that MTAs may parse
+ ;; them safely.
+ (cond ((= end (point)))
+ ((looking-at "[^\000-\177]")
+ (setq end nil))
+ (t
+ (goto-char (1- (match-end 0)))
+ (unless (= (point) (match-beginning 0))
+ (insert " "))))
+ (goto-char end)
+ (skip-chars-forward " \t\n")
+ (if (and (looking-at "[^ \t\n]+")
+ (string-match "[^\000-\177]"
+ (match-string 0)))
+ (setq end nil)
+ (goto-char end)))))))
+ (skip-chars-backward " \t\n")
+ (setq end (point))
+ (goto-char start)
+ (skip-chars-forward "\000-\177" end)
+ (if (= end (point))
+ (setq last-encoded nil)
+ (rfc2047-encode start end)
+ (setq last-encoded t))))))
+ (error
+ (error "Invalid data for rfc2047 encoding: %s"
+ (buffer-substring b e)))))))
(rfc2047-fold-region b (point))))
(defun rfc2047-encode-string (string)
"Encode words in STRING.
By default, the string is treated as containing addresses (see
-`rfc2047-special-chars')."
+`rfc2047-encoding-type')."
(with-temp-buffer
(insert string)
(rfc2047-encode-region (point-min) (point-max))
(buffer-string)))
+(defun rfc2047-encode-1 (column string cs encoder start space &optional eword)
+ "Subroutine used by `rfc2047-encode'."
+ (cond ((string-equal string "")
+ (or eword ""))
+ ((>= column 76)
+ (when (and eword
+ (string-match "\n[ \t]+\\'" eword))
+ ;; Reomove a superfluous empty line.
+ (setq eword (substring eword 0 (match-beginning 0))))
+ (rfc2047-encode-1 (length space) string cs encoder start " "
+ (concat eword "\n" space)))
+ (t
+ (let ((index 0)
+ (limit (1- (length string)))
+ (prev "")
+ next)
+ (while (and prev
+ (<= index limit))
+ (setq next (concat start
+ (funcall encoder
+ (if cs
+ (mm-encode-coding-string
+ (substring string 0 (1+ index))
+ cs)
+ (substring string 0 (1+ index))))
+ "?="))
+ (if (<= (+ column (length next)) 76)
+ (setq prev next
+ index (1+ index))
+ (setq next prev
+ prev nil)))
+ (setq eword (concat eword next))
+ (if (> index limit)
+ eword
+ (when (string-match "\n[ \t]+\\'" eword)
+ ;; Reomove a superfluous empty line.
+ (setq eword (substring eword 0 (match-beginning 0))))
+ (rfc2047-encode-1 (length space) (substring string index)
+ cs encoder start " "
+ (concat eword "\n" space)))))))
+
(defun rfc2047-encode (b e)
"Encode the word(s) in the region B to E.
By default, the region is treated as containing addresses (see
-`rfc2047-special-chars')."
- (let* ((mime-charset (mm-find-mime-charset-region b e))
- (cs (if (> (length mime-charset) 1)
- ;; Fixme: Instead of this, try to break region into
- ;; parts that can be encoded separately.
- (error "Can't rfc2047-encode `%s'"
- (buffer-substring b e))
- (setq mime-charset (car mime-charset))
- (mm-charset-to-coding-system mime-charset)))
- ;; Fixme: Better, calculate the number of non-ASCII
- ;; characters, at least for 8-bit charsets.
- (encoding (if (assq mime-charset
- rfc2047-charset-encoding-alist)
- (cdr (assq mime-charset
+`rfc2047-encoding-type')."
+ (let ((mime-charset (or (mm-find-mime-charset-region b e) (list 'us-ascii)))
+ cs encoding space eword)
+ (cond ((> (length mime-charset) 1)
+ (error "Can't rfc2047-encode `%s'"
+ (buffer-substring-no-properties b e)))
+ ((= (length mime-charset) 1)
+ (setq mime-charset (car mime-charset)
+ cs (mm-charset-to-coding-system mime-charset))
+ (unless (and (mm-multibyte-p)
+ (mm-coding-system-p cs))
+ (setq cs nil))
+ (save-restriction
+ (narrow-to-region b e)
+ (setq encoding
+ (or (cdr (assq mime-charset
rfc2047-charset-encoding-alist))
- 'B))
- (start (concat
- "=?" (downcase (symbol-name mime-charset)) "?"
- (downcase (symbol-name encoding)) "?"))
- (first t))
- (if mime-charset
- (save-restriction
- (narrow-to-region b e)
- (when (eq encoding 'B)
- ;; break into lines before encoding
- (goto-char (point-min))
- (while (not (eobp))
- (goto-char (min (point-max) (+ 15 (point))))
- (unless (eobp)
- (insert ?\n))))
- (if (and (mm-multibyte-p)
- (mm-coding-system-p cs))
- (mm-encode-coding-region (point-min) (point-max) cs))
- (funcall (cdr (assq encoding rfc2047-encoding-function-alist))
- (point-min) (point-max))
- (goto-char (point-min))
- (while (not (eobp))
- (unless first
- (insert ? ))
- (setq first nil)
- (insert start)
- (end-of-line)
- (insert "?=")
- (forward-line 1))))))
+ ;; For the charsets that don't have a preferred
+ ;; encoding, choose the one that's shorter.
+ (if (eq (rfc2047-qp-or-base64) 'base64)
+ 'B
+ 'Q)))
+ (widen)
+ (goto-char b)
+ (unless (= 0 (skip-chars-backward " \t"))
+ (setq space (buffer-substring-no-properties (point) b)))
+ (setq eword (rfc2047-encode-1
+ (- b (point-at-bol))
+ (mm-replace-in-string
+ (buffer-substring-no-properties b e)
+ "\n\\([ \t]?\\)" "\\1")
+ cs
+ (or (cdr (assq encoding
+ rfc2047-encode-function-alist))
+ 'identity)
+ (concat "=?" (downcase (symbol-name mime-charset))
+ "?" (upcase (symbol-name encoding)) "?")
+ (or space " ")))
+ (delete-region (if (eq (aref eword 0) ?\n)
+ (point)
+ (goto-char b))
+ e)
+ (insert eword)
+ (unless (or (eolp)
+ (looking-at "[ \t\n)]"))
+ (insert " "))))
+ (t
+ (goto-char e)))))
(defun rfc2047-fold-field ()
"Fold the current header field."
(first t)
(bol (save-restriction
(widen)
- (rfc2047-point-at-bol))))
+ (point-at-bol))))
(while (not (eobp))
(when (and (or break qword-break)
(> (- (point) bol) 76))
(goto-char (or break qword-break))
(setq break nil
qword-break nil)
+ (skip-chars-backward " \t")
(if (looking-at "[ \t]")
(insert ?\n)
(insert "\n "))
(forward-char 1))
((memq (char-after) '(? ?\t))
(skip-chars-forward " \t")
- (if first
- ;; Don't break just after the header name.
- (setq first nil)
- (setq break (1- (point)))))
+ (unless first ;; Don't break just after the header name.
+ (setq break (point))))
((not break)
(if (not (looking-at "=\\?[^=]"))
(if (eq (char-after) ?=)
(forward-char 1)
(skip-chars-forward "^ \t\n\r="))
- (setq qword-break (point))
+ ;; Don't break at the start of the field.
+ (unless (= (point) b)
+ (setq qword-break (point)))
(skip-chars-forward "^ \t\n\r")))
(t
- (skip-chars-forward "^ \t\n\r"))))
+ (skip-chars-forward "^ \t\n\r")))
+ (setq first nil))
(when (and (or break qword-break)
(> (- (point) bol) 76))
(goto-char (or break qword-break))
(goto-char (point-min))
(let ((bol (save-restriction
(widen)
- (rfc2047-point-at-bol)))
- (eol (rfc2047-point-at-eol))
- leading)
+ (point-at-bol)))
+ (eol (point-at-eol)))
(forward-line 1)
(while (not (eobp))
(if (and (looking-at "[ \t]")
- (< (- (rfc2047-point-at-eol) bol) 76))
+ (< (- (point-at-eol) bol) 76))
(delete-region eol (progn
(goto-char eol)
(skip-chars-forward "\r\n")
(point)))
- (setq bol (rfc2047-point-at-bol)))
- (setq eol (rfc2047-point-at-eol))
+ (setq bol (point-at-bol)))
+ (setq eol (point-at-eol))
(forward-line 1)))))
-(defun rfc2047-b-encode-region (b e)
- "Base64-encode the header contained in region B to E."
- (save-restriction
- (narrow-to-region (goto-char b) e)
- (while (not (eobp))
- (base64-encode-region (point) (progn (end-of-line) (point)) t)
- (if (and (bolp) (eolp))
- (delete-backward-char 1))
- (forward-line))))
-
-(defun rfc2047-q-encode-region (b e)
- "Quoted-printable-encode the header in region B to E."
- (save-excursion
- (save-restriction
- (narrow-to-region (goto-char b) e)
- (let ((alist rfc2047-q-encoding-alist)
- (bol (save-restriction
- (widen)
- (rfc2047-point-at-bol))))
- (while alist
- (when (looking-at (caar alist))
- (quoted-printable-encode-region b e nil (cdar alist))
- (subst-char-in-region (point-min) (point-max) ? ?_)
- (setq alist nil))
- (pop alist))
- ;; The size of QP encapsulation is about 20, so set limit to
- ;; 56=76-20.
- (unless (< (- (point-max) (point-min)) 56)
- ;; Don't break if it could fit in one line.
- ;; Let rfc2047-encode-region break it later.
- (goto-char (1+ (point-min)))
- (while (and (not (bobp)) (not (eobp)))
- (goto-char (min (point-max) (+ 56 bol)))
- (search-backward "=" (- (point) 2) t)
- (unless (or (bobp) (eobp))
- (insert ?\n)
- (setq bol (point)))))))))
+(defun rfc2047-b-encode-string (string)
+ "Base64-encode the header contained in STRING."
+ (base64-encode-string string t))
+
+(defun rfc2047-q-encode-string (string)
+ "Quoted-printable-encode the header in STRING."
+ (mm-with-unibyte-buffer
+ (insert string)
+ (quoted-printable-encode-region
+ (point-min) (point-max) nil
+ ;; = (\075), _ (\137), ? (\077) are used in the encoded word.
+ ;; Avoid using 8bit characters.
+ ;; This list excludes `especials' (see the RFC2047 syntax),
+ ;; meaning that some characters in non-structured fields will
+ ;; get encoded when they con't need to be. The following is
+ ;; what it used to be.
+ ;;; ;; Equivalent to "^\000-\007\011\013\015-\037\200-\377=_?"
+ ;;; "\010\012\014\040-\074\076\100-\136\140-\177")
+ "-\b\n\f !#-'*+0-9A-Z\\^`-~\d")
+ (subst-char-in-region (point-min) (point-max) ? ?_)
+ (buffer-string)))
;;;
;;; Functions for decoding RFC2047 messages
(eval-and-compile
(defconst rfc2047-encoded-word-regexp
- "=\\?\\([^][\000-\040()<>@,\;:\\\"/?.=]+\\)\\?\\(B\\|Q\\)\
-\\?\\([!->@-~ +]*\\)\\?="))
+ "=\\?\\([^][\000-\040()<>@,\;:*\\\"/?.=]+\\)\\(?:\\*[^?]+\\)?\
+\\?\\(B\\|Q\\)\\?\\([!->@-~ ]*\\)\\?="))
;; Fixme: This should decode in place, not cons intermediate strings.
;; Also check whether it needs to worry about delimiting fields like
;; encoding.
+;; In fact it's reported that (invalid) encoding of mailboxes in
+;; addr-specs is in use, so delimiting fields might help. Probably
+;; not decoding a word which isn't properly delimited is good enough
+;; and worthwhile (is it more correct or not?), e.g. something like
+;; `=?iso-8859-1?q?foo?=@'.
+
(defun rfc2047-decode-region (start end)
"Decode MIME-encoded words in region between START and END."
(interactive "r")
(let ((m (mm-multibyte-p)))
(if (string-match "=\\?" string)
(with-temp-buffer
+ ;; Fixme: This logic is wrong, but seems to be required by
+ ;; Gnus summary buffer generation. The value of `m' depends
+ ;; on the current buffer, not global multibyteness or that
+ ;; of the string. Also the string returned should always be
+ ;; multibyte in a multibyte session, i.e. the buffer should
+ ;; be multibyte before `buffer-string' is called.
(when m
(mm-enable-multibyte))
(insert string)
(inline
(rfc2047-decode-region (point-min) (point-max)))
- (mm-enable-multibyte)
- (buffer-string)))
- (if (and mail-parse-charset
- (not (eq mail-parse-charset 'us-ascii))
- (not (eq mail-parse-charset 'gnus-decoded)))
- (mm-decode-coding-string string mail-parse-charset)
- (mm-string-as-multibyte string))))
+ (buffer-string))
+ ;; Fixme: As above, `m' here is inappropriate.
+ (if (and m
+ mail-parse-charset
+ (not (eq mail-parse-charset 'us-ascii))
+ (not (eq mail-parse-charset 'gnus-decoded)))
+ ;; `decode-coding-string' in Emacs offers a third optional
+ ;; arg NOCOPY to avoid consing a new string if the decoding
+ ;; is "trivial". Unfortunately it currently doesn't
+ ;; consider anything else than a `nil' coding system
+ ;; trivial.
+ ;; `rfc2047-decode-string' is called multiple times for each
+ ;; article during summary buffer generation, and we really
+ ;; want to avoid unnecessary consing. So we bypass
+ ;; `decode-coding-string' if the string is purely ASCII.
+ (if (and (fboundp 'detect-coding-string)
+ ;; string is purely ASCII
+ (eq (detect-coding-string string t) 'undecided))
+ string
+ (mm-decode-coding-string string mail-parse-charset))
+ (mm-string-as-multibyte string)))))
(defun rfc2047-parse-and-decode (word)
"Decode WORD and return it if it is an encoded word.
decodable."
(if (not (string-match rfc2047-encoded-word-regexp word))
word
- (condition-case nil
- (rfc2047-decode
- (match-string 1 word)
- (upcase (match-string 2 word))
- (match-string 3 word))
- (error word))))
+ (or
+ (condition-case nil
+ (rfc2047-decode
+ (match-string 1 word)
+ (string-to-char (match-string 2 word))
+ (match-string 3 word))
+ (error word))
+ word))) ; un-decodable
(defun rfc2047-pad-base64 (string)
"Pad STRING to quartets."
;; Be more liberal to accept buggy base64 strings. If
;; base64-decode-string accepts buggy strings, this function could
;; be aliased to identity.
- (case (mod (length string) 4)
- (0 string)
- (1 string) ;; Error, don't pad it.
- (2 (concat string "=="))
- (3 (concat string "="))))
+ (if (= 0 (mod (length string) 4))
+ string
+ (when (string-match "=+$" string)
+ (setq string (substring string 0 (match-beginning 0))))
+ (case (mod (length string) 4)
+ (0 string)
+ (1 string) ;; Error, don't pad it.
+ (2 (concat string "=="))
+ (3 (concat string "=")))))
(defun rfc2047-decode (charset encoding string)
"Decode STRING from the given MIME CHARSET in the given ENCODING.
-Valid ENCODINGs are \"B\" and \"Q\".
+Valid ENCODINGs are the characters \"B\" and \"Q\".
If your Emacs implementation can't decode CHARSET, return nil."
(if (stringp charset)
(setq charset (intern (downcase charset))))
(when (and (eq cs 'ascii)
mail-parse-charset)
(setq cs mail-parse-charset))
- ;; Fixme: What's this for? The following comment makes no sense. -- fx
- (mm-with-unibyte-current-buffer
- ;; In Emacs Mule 4, decoding UTF-8 should be in unibyte mode.
- (mm-decode-coding-string
- (cond
- ((equal "B" encoding)
- (base64-decode-string
- (rfc2047-pad-base64 string)))
- ((equal "Q" encoding)
- (quoted-printable-decode-string
- (mm-replace-chars-in-string string ?_ ? )))
- (t (error "Invalid encoding: %s" encoding)))
- cs)))))
+ (mm-decode-coding-string
+ (cond
+ ((char-equal ?B encoding)
+ (base64-decode-string
+ (rfc2047-pad-base64 string)))
+ ((char-equal ?Q encoding)
+ (quoted-printable-decode-string
+ (mm-subst-char-in-string ?_ ? string t)))
+ (t (error "Invalid encoding: %c" encoding)))
+ cs))))
(provide 'rfc2047)
+;;; arch-tag: a07fe3d4-22b5-4c4a-bd89-b1f82d5d36f6
;;; rfc2047.el ends here