Re: Assert in imap-parse-body, dovecot and rfc822 multipart messages

[Simon Josefsson <jas@extundo.com>]

Tollef Fog Heen <tfheen@err.no> writes:

> (please Cc me on replies, I'm not subscribed)
>
> Hi,
>
> I'm running No Gnus v0.6 accessing my mails over IMAP to a dovecot
> server.  I keep hitting the (assert (eq (char-after) ?\)) nil "In
> imap-parse-body 2").  After enabling the IMAP log I found a line which
> imap-parse-body seems to fail on:
>
> 317 FETCH (UID 894 RFC822.SIZE 32728 BODY (("text" "plain" ("charset" "us-ascii") NIL NIL "7bit" 399 13)("message" "rfc822" NIL NIL NIL "7bit" 29753 ("Sun, 10 Sep 2006 13:34:28 -0500" "Rd. mixture" (("Rob Plummer" NIL "ohw" "garrisevans.com")) (("Rob Plummer" NIL "ohw" "garrisevans.com")) (("Rob Plummer" NIL "ohw" "garrisevans.com")) ((NIL NIL "pkg-config" "lists.freedesktop.org")) NIL NIL NIL "<002201c6d507$e74fed13$871aa4bd@dzvm>") (("text" "plain" ("charset" "windows-1252") NIL NIL "quoted-printable" 1681 29)("text" "html" ("charset" "windows-1252") NIL NIL "quoted-printable" 2818 65) "alternative")("image" "gif" ("name" "ROM.gif") "<001d01c6d507$e74feca0$871aa4bd@dzvm>" NIL "base64" 23392) "related" 450)("message" "rfc822" NIL NIL NIL "7bit" 627 (NIL "confirm a56b2bbbe1f4995adb16bd174f6687fedf79b6d4" ((NIL NIL "pkg-config-request" "lists.freedesktop.org")) ((NIL NIL "pkg-config-request" "lists.freedesktop.org")) ((NIL NIL "pkg-config-request" "lists.freedesktop.org")) NIL NIL NIL NIL NIL) "text" "plain" ("charset" "us-ascii") NIL NIL "7bit" 370 5 12) "mixed") BODY[HEADER.FIELDS (SUBJECT FROM DATE MESSAGE-ID REFERENCES IN-REPLY-TO XREF TO NEWSGROUPS)] {275}
>
> (sorry for the enormous line)
>
> It complains right at the ("image" [...] bit, but I'm not familiar
> enough with IMAP syntax to see whether this is dovecot's fault or
> not.  If the former, could you please explain what's wrong so I could
> look into fixing the bug there?  Thanks for any help, suggestions
> etc; if there is any more information needed, do not hesitate to tell
> me as this has been troubling me for a while now.

Unfortunately, you didn't quote all of the line, you need to continue
to quote the literal following that line, so the parenthesis become
balanced.

I'm afraid I don't have time to debug this, but if someone else wish
to help, a hint is to M-x edebug-defun RET imap-parse-body RET, place
the cursor on first '(' at the 'BODY (("text"' portion and do M-:
(imap-parse-body) RET.  You'll have to single-step through the parser.

To be able to understand what the problem is, you'd probably want to
verify manually that the dovecot output is conforming to the IMAP spec
first.  See RFC 3501.

/Simon