(eval-when-compile
(require 'cl)
- (defvar message-posting-charset)
- (unless (fboundp 'with-syntax-table) ; not in Emacs 20
- (defmacro with-syntax-table (table &rest body)
- "Evaluate BODY with syntax table of current buffer set to TABLE.
-The syntax table of the current buffer is saved, BODY is evaluated, and the
-saved table is restored, even in case of an abnormal exit.
-Value is what BODY returns."
- (let ((old-table (make-symbol "table"))
- (old-buffer (make-symbol "buffer")))
- `(let ((,old-table (syntax-table))
- (,old-buffer (current-buffer)))
- (unwind-protect
- (progn
- (set-syntax-table ,table)
- ,@body)
- (save-current-buffer
- (set-buffer ,old-buffer)
- (set-syntax-table ,old-table))))))))
+ (defvar message-posting-charset))
(require 'qp)
(require 'mm-util)
(require 'base64)
(autoload 'mm-body-7-or-8 "mm-bodies")
-(eval-and-compile
- ;; 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.")
(nil . ignore))
"Alist of RFC2047 encodings to encoding functions.")
+(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'.
(require 'message) ; for message-posting-charset
(let ((charsets
(mm-find-mime-charset-region (point-min) (point-max))))
- (and charsets
- (not (equal charsets (list (car 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
;; is relevant for instance in Subject headers with `Re:' for
;; interoperability with non-MIME clients, and we might as
;; well avoid the tail too.
- (progn
+ (let ((encodable-regexp
+ (if rfc2047-encode-encoded-words
+ "[^\000-\177]\\|=\\?"
+ "[^\000-\177]")))
(goto-char (point-min))
;; Does it need encoding?
- (skip-chars-forward "\000-\177")
+ (re-search-forward encodable-regexp (point-max) 'move)
(unless (eobp)
(skip-chars-backward "^ \n") ; beginning of space-delimited word
- (rfc2047-encode (point) (progn
- (goto-char e)
- (skip-chars-backward "\000-\177")
- (skip-chars-forward "^ \n")
- ;; end of space-delimited word
- (point)))))
+ (rfc2047-encode
+ (point)
+ (progn
+ (goto-char e)
+ (re-search-backward encodable-regexp (point-max) 'move)
+ (skip-chars-forward "^ \n")
+ ;; end of space-delimited word
+ (point)))))
;; `address-mime' case -- take care of quoted words, comments.
(with-syntax-table rfc2047-syntax-table
(let ((start) ; start of current token
(rfc2047-encode start end)
(setq last-encoded t)))))
(error
- (message "Invalid data for rfc2047 encoding: %s"
- (buffer-substring b e)))))))
+ (error "Invalid data for rfc2047 encoding: %s"
+ (buffer-substring b e)))))))
(rfc2047-fold-region b (point))))
(defun rfc2047-encode-string (string)
"Encode the word(s) in the region B to E.
By default, the region is treated as containing addresses (see
`rfc2047-encoding-type')."
- (let* ((mime-charset (mm-find-mime-charset-region b e))
+ (let* ((mime-charset (or (mm-find-mime-charset-region b e) (list 'us-ascii)))
(cs (if (> (length mime-charset) 1)
;; Fixme: Instead of this, try to break region into
;; parts that can be encoded separately.
(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
+ (encoding (or (cdr (assq mime-charset
rfc2047-charset-encoding-alist))
- 'B))
+ ;; For the charsets that don't have a preferred
+ ;; encoding, choose the one that's shorter.
+ (save-restriction
+ (narrow-to-region b e)
+ (if (eq (rfc2047-qp-or-base64) 'base64)
+ 'B
+ 'Q))))
(start (concat
"=?" (downcase (symbol-name mime-charset)) "?"
- (downcase (symbol-name encoding)) "?"))
+ (upcase (symbol-name encoding)) "?"))
+ (factor (case mime-charset
+ ((iso-8859-5 iso-8859-7 iso-8859-8 koi8-r) 1)
+ ((big5 gb2312 euc-kr) 2)
+ (utf-8 4)
+ (t 8)))
+ (pre (- b (save-restriction
+ (widen)
+ (point-at-bol))))
+ ;; encoded-words must not be longer than 75 characters,
+ ;; including charset, encoding etc. This leaves us with
+ ;; 75 - (length start) - 2 - 2 characters. The last 2 is for
+ ;; possible base64 padding. In the worst case (iso-2022-*)
+ ;; each character expands to 8 bytes which is expanded by a
+ ;; factor of 4/3 by base64 encoding.
+ (length (floor (- 75 (length start) 4) (* factor (/ 4.0 3.0))))
+ ;; Limit line length to 76 characters.
+ (length1 (max 1 (floor (- 76 (length start) 4 pre)
+ (* factor (/ 4.0 3.0)))))
(first t))
(if mime-charset
(save-restriction
;; break into lines before encoding
(goto-char (point-min))
(while (not (eobp))
- (goto-char (min (point-max) (+ 15 (point))))
+ (if first
+ (progn
+ (goto-char (min (point-max) (+ length1 (point))))
+ (setq first nil))
+ (goto-char (min (point-max) (+ length (point)))))
(unless (eobp)
- (insert ?\n))))
+ (insert ?\n)))
+ (setq first t))
(if (and (mm-multibyte-p)
(mm-coding-system-p cs))
(mm-encode-coding-region (point-min) (point-max) cs))
(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))
(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"))))
(goto-char (point-min))
(let ((bol (save-restriction
(widen)
- (rfc2047-point-at-bol)))
- (eol (rfc2047-point-at-eol)))
+ (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)
(narrow-to-region (goto-char b) e)
(let ((bol (save-restriction
(widen)
- (rfc2047-point-at-bol))))
+ (point-at-bol))))
(quoted-printable-encode-region
b e nil
;; = (\075), _ (\137), ? (\077) are used in the encoded word.
(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
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)
+ ;; `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)
(condition-case nil
(rfc2047-decode
(match-string 1 word)
- (upcase (match-string 2 word))
+ (string-to-char (match-string 2 word))
(match-string 3 word))
(error word))
word))) ; un-decodable
;; 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))))
(setq cs mail-parse-charset))
(mm-decode-coding-string
(cond
- ((equal "B" encoding)
+ ((char-equal ?B encoding)
(base64-decode-string
(rfc2047-pad-base64 string)))
- ((equal "Q" encoding)
+ ((char-equal ?Q encoding)
(quoted-printable-decode-string
- (mm-replace-chars-in-string string ?_ ? )))
- (t (error "Invalid encoding: %s" encoding)))
+ (mm-subst-char-in-string ?_ ? string t)))
+ (t (error "Invalid encoding: %c" encoding)))
cs))))
(provide 'rfc2047)