Re: master ef14acf: Make nnml handle invalid non-ASCII headers more consistently

[Florian Weimer <fweimer@redhat.com>]

* Eli Zaretskii:

>> From: Florian Weimer <fweimer@redhat.com>
>> Cc: Lars Ingebrigtsen <larsi@gnus.org>,  Eric Abrahamsen
>>  <eric@ericabrahamsen.net>,  emacs-devel@gnu.org,  ding@gnus.org
>> Date: Sat, 17 Dec 2022 15:57:18 +0100
>> 
>> >> Mail source (maildir :path …) failed: (error Invalid data for rfc2047 encoding: 罗勇刚(Yonggang Luo) via Elfutils-devel <elfutils-devel@sourceware.org>)
>> >> 
>> >> On an older Emacs without this change, it seems that the original header
>> >> is written to the .overview file, which sidestep the problem that not
>> >> all strings are encodable by the rfc2047 functions.
>> >
>> > Thanks.  I guess this From header is invalid because there's no space
>> > between the "罗勇刚" and the "(Yonggang Luo)" parts?
>> 
>> Yes, that seems to be what's tripping the encoder.  But I'm not sure if
>> proper encoding of ( or ) (as =28 or =29 using the Q encoding, or using
>> the B encoding as in the raw text) is actually invalid.  RFC 2047 only
>> talks about unencoded ( or ).  In contrast, encoded ( and ) are valid
>> syntax at the RFC 822 layer because encoding hides them.
>
> I'm not sure this is related.  I was talking about the missing SPC
> character before the parentheses.  But I know very little about this
> stuff, so maybe I'm just misunderstanding you.

I was responding to “this From header is invalid”.  I'm not sure if the
original message is actually malformed.

>> I somehow can't reproduce the original issue.  I expect more problematic
>> messages to arrive next week, though, and will report then how it goes.
>
> Thanks.  Please do get back, even if you don't succeed in reproducing.

As I expected, I could reproduce the issue with new mail.  I'm happy to
report that replacing nnml--encode-headers with your new version fixes
the issue.

Going back to older mail, I see that previously the From: header was
written in encoded form to .overview (slightly wrapped to avoid SMTP
issues):

8523 Re: [PATCH 1/7] Rename 'hello2.spec.' -> 'hello2.spec' 'hello3.spec.' -> 'hello3.spec' =?utf-8?b?572X5YuH5YiaKFlvbmdnYW5nIEx1bykgdmlhIEVsZnV0aWxzLWRldmVs?= <elfutils-devel@sourceware.org> Thu, 24 Nov 2022 16:27:56 +0800 <CAE2XoE_RBNdsPZMLiSQKJroyx4ycvqf7y+VDbuY=-XbhOwsL8g@mail.gmail.com>
  <20220920084307.1696-1-luoyonggang@gmail.com> <20220920084307.1696-2-luoyonggang@gmail.com> <Y0nH98k6YumMRSz0@wildebeest.org> <CAE2XoE-xfFQNMN1JYSi8Kp+-DUUookRkzwUV+OvKGfnZKDXKEA@mail.gmail.com> <20221019194930.GC24703@redhat.com> <3bf19d05c8976411432709fae1cc2bcc2d21d700.camel@klomp.org>
  <586fbfd512763e539f0d06e8ffa308da34be5368.camel@wildebeest.org> 705 32 Xref: oldenburg.str.redhat.com lists.sourceware.elfutils-devel:8523 Cc: "Frank Ch. Eigler" <fche@redhat.com>, elfutils-devel@sourceware.org To: Mark Wielaard <aegon@wildebeest.org>

Now it uses unencoded form:

8762 Re: [PATCH v2 13/16] lib: isatty is not available on windows 罗勇刚(Yonggang Luo) via Elfutils-devel <elfutils-devel@sourceware.org> Mon, 19 Dec 2022 20:32:48 +0800 <CAE2XoE-Xv6+4Npj38ih_nPMZ8e6ph7oS8wxvKFx1uE-sRfH_kw@mail.gmail.com> <20221217165213.152-1-luoyonggang@gmail.com>
  <20221217165213.152-14-luoyonggang@gmail.com> 1074 43 Xref: oldenburg.str.redhat.com lists.sourceware.elfutils-devel:8762 To: elfutils-devel@sourceware.org

I assume that there is some protection in place that tabs are not
possible here?

Thanks,
Florian