(rfc2047-header-encoding-alist): Add In-Reply-To to address-mime.
[gnus] / lisp / rfc2047.el
index 34683c3..081ba9b 100644 (file)
@@ -44,7 +44,7 @@
   '(("Newsgroups" . nil)
     ("Followup-To" . nil)
     ("Message-ID" . nil)
-    ("\\(Resent-\\)?\\(From\\|Cc\\|To\\|Bcc\\|Reply-To\\|Sender\
+    ("\\(Resent-\\)?\\(From\\|Cc\\|To\\|Bcc\\|\\(In-\\)?Reply-To\\|Sender\
 \\|Mail-Followup-To\\|Mail-Copies-To\\|Approved\\)" . address-mime)
     (t . mime))
   "*Header/encoding method alist.
@@ -159,24 +159,25 @@ Should be called narrowed to the head of the message."
          (rfc2047-narrow-to-field)
          (if (not (rfc2047-encodable-p))
              (prog1
-               (if (and (eq (mm-body-7-or-8) '8bit)
-                        (mm-multibyte-p)
-                        (mm-coding-system-p
-                         (car message-posting-charset)))
-                   ;; 8 bit must be decoded.
-                   (mm-encode-coding-region
-                    (point-min) (point-max)
-                    (mm-charset-to-coding-system
-                     (car message-posting-charset))))
+                 (if (and (eq (mm-body-7-or-8) '8bit)
+                          (mm-multibyte-p)
+                          (mm-coding-system-p
+                           (car message-posting-charset)))
+                     ;; 8 bit must be decoded.
+                     (mm-encode-coding-region
+                      (point-min) (point-max)
+                      (mm-charset-to-coding-system
+                       (car message-posting-charset))))
                ;; No encoding necessary, but folding is nice
-               (rfc2047-fold-region
-                (save-excursion
-                  (goto-char (point-min))
-                  (skip-chars-forward "^:")
-                  (when (looking-at ": ")
-                    (forward-char 2))
-                  (point))
-                (point-max)))
+               (when nil
+                 (rfc2047-fold-region
+                  (save-excursion
+                    (goto-char (point-min))
+                    (skip-chars-forward "^:")
+                    (when (looking-at ": ")
+                      (forward-char 2))
+                    (point))
+                  (point-max))))
            ;; We found something that may perhaps be encoded.
            (setq method nil
                  alist rfc2047-header-encoding-alist)
@@ -186,7 +187,6 @@ Should be called narrowed to the head of the message."
                        (eq (car elem) t))
                (setq alist nil
                      method (cdr elem))))
-           (goto-char (point-min))
            (re-search-forward "^[^:]+: *" nil t)
            (cond
             ((eq method 'address-mime)
@@ -270,8 +270,8 @@ The buffer may be narrowed."
                              table))))
     (modify-syntax-entry ?\\ "\\" table)
     (modify-syntax-entry ?\" "\"" table)
-    (modify-syntax-entry ?\( "." table)
-    (modify-syntax-entry ?\) "." table)
+    (modify-syntax-entry ?\( "(" table)
+    (modify-syntax-entry ?\) ")" table)
     (modify-syntax-entry ?\< "." table)
     (modify-syntax-entry ?\> "." table)
     (modify-syntax-entry ?\[ "." table)
@@ -289,13 +289,14 @@ Dynamically bind `rfc2047-encoding-type' to change that."
   (save-restriction
     (narrow-to-region b e)
     (let ((encodable-regexp (if rfc2047-encode-encoded-words
-                               "[^\000-\177]\\|=\\?"
-                             "[^\000-\177]"))
+                               "[^\000-\177]+\\|=\\?"
+                             "[^\000-\177]+"))
          start                         ; start of current token
-         end                           ; end of current token
+         end begin csyntax
          ;; Whether there's an encoded word before the current token,
          ;; either immediately or separated by space.
-         last-encoded)
+         last-encoded
+         (orig-text (buffer-substring-no-properties b e)))
       (if (eq 'mime rfc2047-encoding-type)
          ;; Simple case.  Continuous words in which all those contain
          ;; non-ASCII characters are encoded collectively.  Encoding
@@ -318,7 +319,7 @@ Dynamically bind `rfc2047-encoding-type' to change that."
        ;; `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 err           ; in case of unbalanced quotes
              ;; Look for rfc2822-style: sequences of atoms, quoted
              ;; strings, specials, whitespace.  (Specials mustn't be
              ;; encoded.)
@@ -329,137 +330,185 @@ Dynamically bind `rfc2047-encoding-type' to change that."
                (cond
                 ((not (char-after)))   ; eob
                 ;; else token start
-                ((eq ?\" (char-syntax (char-after)))
+                ((eq ?\" (setq csyntax (char-syntax (char-after))))
                  ;; Quoted word.
                  (forward-sexp)
                  (setq end (point))
                  ;; Does it need encoding?
                  (goto-char start)
-                 (skip-chars-forward "\000-\177" end)
-                 (if (= end (point))
-                     (setq last-encoded  nil)
-                   ;; It needs encoding.  Strip the quotes first,
-                   ;; since encoded words can't occur in quotes.
-                   (goto-char end)
-                   (delete-backward-char 1)
-                   (goto-char start)
-                   (delete-char 1)
-                   (when last-encoded
-                     ;; There was a preceding quoted word.  We need
-                     ;; to include any separating whitespace in this
-                     ;; word to avoid it getting lost.
-                     (skip-chars-backward " \t")
-                     ;; A space is needed between the encoded words.
-                     (insert ? )
-                     (setq start (point)
-                           end (1+ end)))
-                   ;; Adjust the end position for the deleted quotes.
-                   (rfc2047-encode start (- end 2))
-                   (setq last-encoded t))) ; record that it was encoded
-                ((eq ?. (char-syntax (char-after)))
+                 (if (re-search-forward encodable-regexp end 'move)
+                     ;; It needs encoding.  Strip the quotes first,
+                     ;; since encoded words can't occur in quotes.
+                     (progn
+                       (goto-char end)
+                       (delete-backward-char 1)
+                       (goto-char start)
+                       (delete-char 1)
+                       (when last-encoded
+                         ;; There was a preceding quoted word.  We need
+                         ;; to include any separating whitespace in this
+                         ;; word to avoid it getting lost.
+                         (skip-chars-backward " \t")
+                         ;; A space is needed between the encoded words.
+                         (insert ? )
+                         (setq start (point)
+                               end (1+ end)))
+                       ;; Adjust the end position for the deleted quotes.
+                       (rfc2047-encode start (- end 2))
+                       (setq last-encoded t)) ; record that it was encoded
+                   (setq last-encoded  nil)))
+                ((eq ?. csyntax)
                  ;; Skip other delimiters, but record that they've
                  ;; potentially separated quoted words.
                  (forward-char)
                  (setq last-encoded nil))
+                ((eq ?\) csyntax)
+                 (error "Unbalanced parentheses"))
+                ((eq ?\( csyntax)
+                 ;; Look for the end of parentheses.
+                 (forward-list)
+                 ;; Encode text as an unstructured field.
+                 (let ((rfc2047-encoding-type 'mime))
+                   (rfc2047-encode-region (1+ start) (1- (point))))
+                 (skip-chars-forward ")"))
                 (t                 ; normal token/whitespace sequence
                  ;; Find the end.
+                 ;; Skip one ASCII word, or encode continuous words
+                 ;; in which all those contain non-ASCII characters.
+                 (setq end nil)
+                 (while (not (or end (eobp)))
+                   (when (looking-at "[\000-\177]+")
+                     (setq begin (point)
+                           end (match-end 0))
+                     (when (progn
+                             (while (and (or (re-search-forward
+                                              "[ \t\n]\\|\\Sw" end 'move)
+                                             (setq end nil))
+                                         (eq ?\\ (char-syntax (char-before))))
+                               ;; Skip backslash-quoted characters.
+                               (forward-char))
+                             end)
+                       (setq end (match-beginning 0))
+                       (if rfc2047-encode-encoded-words
+                           (progn
+                             (goto-char begin)
+                             (when (search-forward "=?" end 'move)
+                               (goto-char (match-beginning 0))
+                               (setq end nil)))
+                         (goto-char end))))
+                   ;; Where the value nil of `end' means there may be
+                   ;; text to have to be encoded following the point.
+                   ;; Otherwise, the point reached to the end of ASCII
+                   ;; words separated by whitespace or a special char.
+                   (unless end
+                     (when (looking-at encodable-regexp)
+                       (goto-char (setq begin (match-end 0)))
+                       (while (and (looking-at "[ \t\n]+\\([^ \t\n]+\\)")
+                                   (setq end (match-end 0))
+                                   (progn
+                                     (while (re-search-forward
+                                             encodable-regexp end t))
+                                     (< begin (point)))
+                                   (goto-char begin)
+                                   (or (not (re-search-forward "\\Sw" end t))
+                                       (progn
+                                         (goto-char (match-beginning 0))
+                                         nil)))
+                         (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 (concat "\\sw*\\("
+                                                        encodable-regexp
+                                                        "\\)"))
+                                    (setq end nil))
+                                   (t
+                                    (goto-char (1- (match-end 0)))
+                                    (unless (= (point) (match-beginning 0))
+                                      ;; Separate encodable text and
+                                      ;; delimiter.
+                                      (insert " "))))
+                           (goto-char end)
+                           (skip-chars-forward " \t\n")
+                           (if (and (looking-at "[^ \t\n]+")
+                                    (string-match encodable-regexp
+                                                  (match-string 0)))
+                               (setq end nil)
+                             (goto-char end)))))))
                  (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))))))
+                 (setq end (point))
+                 (goto-char start)
+                 (if (re-search-forward encodable-regexp end 'move)
+                     (progn
+                       (unless (memq (char-before start) '(nil ?\t ? ))
+                         (if (progn
+                               (goto-char start)
+                               (skip-chars-backward "^ \t\n")
+                               (and (looking-at "\\Sw+")
+                                    (= (match-end 0) start)))
+                             ;; Also encode bogus delimiters.
+                             (setq start (point))
+                           ;; Separate encodable text and delimiter.
+                           (goto-char start)
+                           (insert " ")
+                           (setq start (1+ start)
+                                 end (1+ end))))
+                       (rfc2047-encode start end)
+                       (setq last-encoded t))
+                   (setq last-encoded nil)))))
            (error
-            (error "Invalid data for rfc2047 encoding: %s"
-                   (buffer-substring b e)))))))
-    (rfc2047-fold-region b (point))))
+            (if (or debug-on-quit debug-on-error)
+                (signal (car err) (cdr err))
+              (error "Invalid data for rfc2047 encoding: %s"
+                     (mm-replace-in-string orig-text "[ \t\n]+" " "))))))))
+    (rfc2047-fold-region b (point))
+    (goto-char (point-max))))
 
 (defun rfc2047-encode-string (string)
   "Encode words in STRING.
 By default, the string is treated as containing addresses (see
 `rfc2047-encoding-type')."
-  (with-temp-buffer
+  (mm-with-multibyte-buffer
     (insert string)
     (rfc2047-encode-region (point-min) (point-max))
     (buffer-string)))
 
-(defun rfc2047-encode-1 (column string cs encoder start space &optional eword)
+(defvar rfc2047-encode-max-chars 76
+  "Maximum characters of each header line that contain encoded-words.
+If it is nil, encoded-words will not be folded.  Too small value may
+cause an error.  Don't change this for no particular reason.")
+
+(defun rfc2047-encode-1 (column string cs encoder start crest tail
+                               &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)))
+       ((not rfc2047-encode-max-chars)
+        (concat start
+                (funcall encoder (if cs
+                                     (mm-encode-coding-string string cs)
+                                   string))
+                "?="))
+       ((>= column rfc2047-encode-max-chars)
+        (when eword
+          (cond ((string-match "\n[ \t]+\\'" eword)
+                 ;; Reomove a superfluous empty line.
+                 (setq eword (substring eword 0 (match-beginning 0))))
+                ((string-match "(+\\'" eword)
+                 ;; Break the line before the open parenthesis.
+                 (setq crest (concat crest (match-string 0 eword))
+                       eword (substring eword 0 (match-beginning 0))))))
+        (rfc2047-encode-1 (length crest) string cs encoder start " " tail
+                          (concat eword "\n" crest)))
        (t
         (let ((index 0)
               (limit (1- (length string)))
               (prev "")
-              next)
+              next len)
           (while (and prev
                       (<= index limit))
             (setq next (concat start
@@ -469,28 +518,48 @@ By default, the string is treated as containing addresses (see
                                              (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))
+                               "?=")
+                  len (+ column (length next)))
+            (if (> len rfc2047-encode-max-chars)
+                (setq next prev
+                      prev nil)
+              (if (or (< index limit)
+                      (<= (+ len (or (string-match "\n" tail)
+                                     (length tail)))
+                          rfc2047-encode-max-chars))
+                  (setq prev next
+                        index (1+ index))
+                (if (string-match "\\`)+" tail)
+                    ;; Break the line after the close parenthesis.
+                    (setq tail (concat (substring tail 0 (match-end 0))
+                                       "\n "
+                                       (substring tail (match-end 0)))
+                          prev next
+                          index (1+ index))
+                  (setq next prev
+                        prev nil)))))
           (if (> index limit)
-              eword
+              (concat eword next tail)
+            (if (= 0 index)
+                (if (and eword
+                         (string-match "(+\\'" eword))
+                    (setq crest (concat crest (match-string 0 eword))
+                          eword (substring eword 0 (match-beginning 0)))
+                  (setq eword (concat eword next)))
+              (setq crest " "
+                    eword (concat eword next)))
             (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)))))))
+            (rfc2047-encode-1 (length crest) (substring string index)
+                              cs encoder start " " tail
+                              (concat eword "\n" crest)))))))
 
 (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-encoding-type')."
+Point moves to the end of the region."
   (let ((mime-charset (or (mm-find-mime-charset-region b e) (list 'us-ascii)))
-       cs encoding space eword)
+       cs encoding tail crest eword)
     (cond ((> (length mime-charset) 1)
           (error "Can't rfc2047-encode `%s'"
                  (buffer-substring-no-properties b e)))
@@ -511,9 +580,19 @@ By default, the region is treated as containing addresses (see
                           'B
                         'Q)))
             (widen)
+            (goto-char e)
+            (skip-chars-forward "^ \t\n")
+            ;; `tail' may contain a close parenthesis.
+            (setq tail (buffer-substring-no-properties e (point)))
             (goto-char b)
+            (setq b (point-marker)
+                  e (set-marker (make-marker) e))
+            (rfc2047-fold-region (point-at-bol) b)
+            (goto-char b)
+            (skip-chars-backward "^ \t\n")
             (unless (= 0 (skip-chars-backward " \t"))
-              (setq space (buffer-substring-no-properties (point) b)))
+              ;; `crest' may contain whitespace and an open parenthesis.
+              (setq crest (buffer-substring-no-properties (point) b)))
             (setq eword (rfc2047-encode-1
                          (- b (point-at-bol))
                          (mm-replace-in-string
@@ -525,13 +604,21 @@ By default, the region is treated as containing addresses (see
                              'identity)
                          (concat "=?" (downcase (symbol-name mime-charset))
                                  "?" (upcase (symbol-name encoding)) "?")
-                         (or space " ")))
+                         (or crest " ")
+                         tail))
             (delete-region (if (eq (aref eword 0) ?\n)
-                               (point)
+                               (if (bolp)
+                                   ;; The line was folded before encoding.
+                                   (1- (point))
+                                 (point))
                              (goto-char b))
-                           e)
+                           (+ e (length tail)))
+            ;; `eword' contains `crest' and `tail'.
             (insert eword)
-            (unless (or (eolp)
+            (set-marker b nil)
+            (set-marker e nil)
+            (unless (or (/= 0 (length tail))
+                        (eobp)
                         (looking-at "[ \t\n)]"))
               (insert " "))))
          (t
@@ -602,9 +689,10 @@ By default, the region is treated as containing addresses (see
        (goto-char (or break qword-break))
        (setq break nil
              qword-break nil)
-         (if (looking-at "[ \t]")
-             (insert ?\n)
-           (insert "\n "))
+       (if (or (> 0 (skip-chars-backward " \t"))
+               (looking-at "[ \t]"))
+           (insert ?\n)
+         (insert "\n "))
        (setq bol (1- (point)))
        ;; Don't break before the first non-LWSP characters.
        (skip-chars-forward " \t")
@@ -661,6 +749,28 @@ By default, the region is treated as containing addresses (see
     (subst-char-in-region (point-min) (point-max) ?  ?_)
     (buffer-string)))
 
+(defun rfc2047-encode-parameter (param value)
+  "Return and PARAM=VALUE string encoded in the RFC2047-like style.
+This is a replacement for the `rfc2231-encode-string' function.
+
+When attaching files as MIME parts, we should use the RFC2231 encoding
+to specify the file names containing non-ASCII characters.  However,
+many mail softwares don't support it in practice and recipients won't
+be able to extract files with correct names.  Instead, the RFC2047-like
+encoding is acceptable generally.  This function provides the very
+RFC2047-like encoding, resigning to such a regrettable trend.  To use
+it, put the following line in your ~/.gnus.el file:
+
+\(defalias 'mail-header-encode-parameter 'rfc2047-encode-parameter)
+"
+  (let* ((rfc2047-encoding-type 'mime)
+        (rfc2047-encode-max-chars nil)
+        (string (rfc2047-encode-string value)))
+    (if (string-match "[][()<>@,;:\\\"/?=]" ;; tspecials
+                     string)
+       (format "%s=%S" param string)
+      (concat param "=" string))))
+
 ;;;
 ;;; Functions for decoding RFC2047 messages
 ;;;
@@ -810,9 +920,8 @@ If your Emacs implementation can't decode CHARSET, return nil."
             (memq 'gnus-unknown mail-parse-ignored-charsets))
        (setq cs (mm-charset-to-coding-system mail-parse-charset)))
     (when cs
-      (when (and (eq cs 'ascii)
-                mail-parse-charset)
-       (setq cs mail-parse-charset))
+      (when (eq cs 'ascii)
+       (setq cs (or mail-parse-charset 'raw-text)))
       (mm-decode-coding-string
        (cond
        ((char-equal ?B encoding)