bug#43597: 28.0.50; arc-mode.el fails to display a ZIP file

[Stephen Berman]

On Fri, 25 Sep 2020 14:00:33 +0300 Eli Zaretskii <eliz@gnu.org> wrote:

>> Date: Fri, 25 Sep 2020 12:53:25 +0300
>> From: Eli Zaretskii <eliz@gnu.org>
>> Cc: 43597@debbugs.gnu.org
>>
>> > Date: Fri, 25 Sep 2020 12:37:31 +0300
>> > From: Eli Zaretskii <eliz@gnu.org>
>> > Cc: 43597@debbugs.gnu.org
>> >
>> > Where can I find a zip file which exhibits this problem?
>>
>> Never mind, I found such a file on my system, the same one I used when
>> I added the zip64 support.  The code indeed bit-rotted since then, I'm
>> looking into this.
>
> With the file I have, replacing -1 by #xffffffff does the job.  So I
> guess I will need the file you used after all.  It could be either the
> file's contents, or maybe there are issues related to whether Emacs is
> a 32-bit (my case) or a 64-bit (your case) program.

I can't readily make that specific file available to you (I would have
to get permission to share it), but fortunately the server I downloaded
it from automatically creates such ZIP files, so I just uploaded two
small test files to the server and downloaded them as a ZIP file, and it
shows exactly the same behavior (trying to visit it in archive-mode
fails with -1 but not with #xffffffff, but with the latter the size of
each of the files in the archive is given as #xffffffff), so it should
serve for debugging.  I've attached that ZIP file.

Steve Berman

test.zip
Description: Zip archive