Merge from emacs--devo--0

[gnu-emacs] / lisp / gnus / rfc2047.el

diff --git a/lisp/gnus/rfc2047.el b/lisp/gnus/rfc2047.el
index b789061853fdd2900595c455f518a85e50fcf663..aa9999a77222065ed0c8c53e33b4a54c0632c3ff 100644 (file)
--- a/lisp/gnus/rfc2047.el
+++ b/lisp/gnus/rfc2047.el
@@ -30,8 +30,8 @@
 ;;; Code:
 
 (eval-when-compile
-  (require 'cl)
-  (defvar message-posting-charset))
+  (require 'cl))
+(defvar message-posting-charset)
 
 (require 'qp)
 (require 'mm-util)
@@ -101,6 +101,40 @@ quoted-printable and base64 respectively.")
 (defvar rfc2047-encode-encoded-words t
   "Whether encoded words should be encoded again.")
 
+(defvar rfc2047-allow-irregular-q-encoded-words t
+  "*Whether to decode irregular Q-encoded words.")
+
+(eval-and-compile ;; Necessary to hard code them in `rfc2047-decode-region'.
+  (defconst rfc2047-encoded-word-regexp
+    "=\\?\\([^][\000-\040()<>@,\;:*\\\"/?.=]+\\)\\(?:\\*[^?]+\\)?\\?\
+\\(B\\?[+/0-9A-Za-z]*=*\
+\\|Q\\?[ ->@-~]*\
+\\)\\?="
+    "Regexp that matches encoded word."
+    ;; The patterns for the B encoding and the Q encoding, i.e. the ones
+    ;; beginning with "B" and "Q" respectively, are restricted into only
+    ;; the characters that those encodings may generally use.
+    )
+  (defconst rfc2047-encoded-word-regexp-loose
+    "=\\?\\([^][\000-\040()<>@,\;:*\\\"/?.=]+\\)\\(?:\\*[^?]+\\)?\\?\
+\\(B\\?[+/0-9A-Za-z]*=*\
+\\|Q\\?\\(?:\\?+[ -<>@-~]\\)?\\(?:[ ->@-~]+\\?+[ -<>@-~]\\)*[ ->@-~]*\\?*\
+\\)\\?="
+    "Regexp that matches encoded word allowing loose Q encoding."
+    ;; The pattern for the Q encoding, i.e. the one beginning with "Q",
+    ;; is similar to:
+    ;; "Q\\?\\(\\?+[^\n=?]\\)?\\([^\n?]+\\?+[^\n=?]\\)*[^\n?]*\\?*"
+    ;;      <--------1-------><----------2,3----------><--4--><-5->
+    ;; They mean:
+    ;; 1. After "Q?", allow "?"s that follow a character other than "=".
+    ;; 2. Allow "=" after "Q?"; it isn't regarded as the terminator.
+    ;; 3. In the middle of an encoded word, allow "?"s that follow a
+    ;;    character other than "=".
+    ;; 4. Allow any characters other than "?" in the middle of an
+    ;;    encoded word.
+    ;; 5. At the end, allow "?"s.
+    ))
+
 ;;;
 ;;; Functions for encoding RFC2047 messages
 ;;;
@@ -287,7 +321,6 @@ Should be called narrowed to the head of the message."
 
 ;; Fixme: This, and the require below may not be the Right Thing, but
 ;; should be safe just before release.  -- fx 2001-02-08
-(eval-when-compile (defvar message-posting-charset))
 
 (defun rfc2047-encodable-p ()
   "Return non-nil if any characters in current buffer need encoding in headers.
@@ -298,7 +331,7 @@ The buffer may be narrowed."
     (goto-char (point-min))
     (or (and rfc2047-encode-encoded-words
             (prog1
-                (search-forward "=?" nil t)
+                (re-search-forward rfc2047-encoded-word-regexp nil t)
               (goto-char (point-min))))
        (and charsets
             (not (equal charsets (list (car message-posting-charset))))))))
@@ -533,10 +566,19 @@ By default, the string is treated as containing addresses (see
     (rfc2047-encode-region (point-min) (point-max))
     (buffer-string)))
 
+;; From RFC 2047:
+;; 2. Syntax of encoded-words
+;;    [...]
+;;    While there is no limit to the length of a multiple-line header
+;;    field, each line of a header field that contains one or more
+;;    'encoded-word's is limited to 76 characters.
+;;
+;; In `rfc2047-encode-parameter' it is bound to nil, so don't defconst it.
 (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.")
+According to RFC 2047, it is 76.  If it is nil, encoded-words
+will not be folded.  Too small value may cause an error.  You
+should not change this value.")
 
 (defun rfc2047-encode-1 (column string cs encoder start crest tail
                                &optional eword)
@@ -827,11 +869,6 @@ it, put the following line in your ~/.gnus.el file:
 ;;; Functions for decoding RFC2047 messages
 ;;;
 
-(eval-and-compile
-  (defconst rfc2047-encoded-word-regexp
-    "=\\?\\([^][\000-\040()<>@,\;:*\\\"/?.=]+\\)\\(?:\\*[^?]+\\)?\
-\\?\\(B\\|Q\\)\\?\\([!->@-~ ]*\\)\\?="))
-
 (defvar rfc2047-quote-decoded-words-containing-tspecials nil
   "If non-nil, quote decoded words containing special characters.")
 
@@ -950,10 +987,12 @@ If ADDRESS-MIME is non-nil, strip backslashes which precede characters
 other than `\"' and `\\' in quoted strings."
   (interactive "r")
   (let ((case-fold-search t)
-       (eword-regexp (eval-when-compile
-                       ;; Ignore whitespace between encoded-words.
-                       (concat "[\n\t ]*\\(" rfc2047-encoded-word-regexp
-                               "\\)")))
+       (eword-regexp
+        (if rfc2047-allow-irregular-q-encoded-words
+            (eval-when-compile
+              (concat "[\n\t ]*\\(" rfc2047-encoded-word-regexp-loose "\\)"))
+          (eval-when-compile
+            (concat "[\n\t ]*\\(" rfc2047-encoded-word-regexp "\\)"))))
        b e match words)
     (save-excursion
       (save-restriction
@@ -969,7 +1008,7 @@ other than `\"' and `\\' in quoted strings."
          (while match
            (push (list (match-string 2) ;; charset
                        (char-after (match-beginning 3)) ;; encoding
-                       (match-string 4) ;; encoded-text
+                       (substring (match-string 3) 2) ;; encoded-text
                        (match-string 1)) ;; encoded-word
                  words)
            ;; Look for the subsequent encoded-words.