On 2017-05-02, tiggersWelt.net (Support) <supp...@tiggerswelt.net> wrote: > Am 01.05.2017 um 22:40 schrieb Grant Edwards: >> The Busybox 'unzip' utility returns a failure status and prints an >> error message when it's given an properly formatted (but empty) zip >> archive. >> >> $ hexdump -C empty.zip >> 00000000 50 4b 05 06 00 00 00 00 00 00 00 00 00 00 00 00 >> |PK..............| >> 00000010 00 00 00 00 00 00 |......| >> 00000016 >> >> $ file empty.zip >> empty.zip: Zip archive data (empty) >> >> $ busybox unzip empty.zip || echo FAIL >> Archive: empty.zip >> unzip: invalid zip magic 06054B50 >> FAIL >> >> Why is that an error? > > Just to give you a short answer (without having fixed the issue yet): > > At the point of error (unzip.c:656) busybox is not prepared to handle a > Central-Directory-End-Magic (0x06054B50), but the ZIP-File seems valid [0].
Yes, I'm pretty sure it's valid. I've got several different utilities that produce that identical file when you tell them to create a zip archive of an empty directory (or when you delete the last file in a zip archive). I've also found numerous references saying that an empty zip file comprises those exact 22 bytes and show other ways to create one: http://stackoverflow.com/questions/25195495/how-to-create-an-empty-zip-file http://stackoverflow.com/questions/29234912/how-to-create-minimum-size-empty-zip-file-which-has-22b > It should be easy to catch the signature there and just stop processing. > But as I'm new to this code, I don't know if there are any side-effects. > > [0] https://www.iana.org/assignments/media-types/application/zip > See "General Format of a ZIP file" - everything is optional > except a CDE at EOF (which may also be BOF if no other parts are > present) -- Grant Edwards grant.b.edwards Yow! I think my career at is ruined! gmail.com _______________________________________________ busybox mailing list busybox@busybox.net http://lists.busybox.net/mailman/listinfo/busybox
