Re: Status of deb(5) format support in Debian

[David Kalnischkies <kalnischkies@gmail.com>]

On Wed, Jul 31, 2013 at 6:56 PM, Stefano Zacchiroli <zack@debian.org> wrote:
> On Wed, Jul 31, 2013 at 06:24:32PM +0200, Guillem Jover wrote:
>> Due to bug 718295, and in preparation to add non-gzip compression
>> support for control.tar, I've tried to get an accurate view of the
>> current deb(5) format support in software present in Debian. The
>> resulting table looks pretty bad:
>>
>>    <https://wiki.debian.org/Teams/Dpkg/DebSupport>
>
> So, about the following passage on that page:
>
>> The current support seems quite bleak, and part of the blame goes to
>> dpkg for not providing better interfaces for others to use, hopefully
>> that will be remedied soon.
>
> Can you expand on the planned remedy and in how "soon" it might arrive?

That I would be interested in as well.

APT (or better: libapt-inst) is containing this tar stuff for two reasons:
1) apt-extracttemplates – which is a hack/layer violation as that is really
   something a dpkg-* (or debconf) tool should do but its still here…
   [Its on the roadmap for dpkg since at least 1.15.X (according to wiki).]
2) apt-ftparchive – used to generate Contents files (which seem to be
   slightly different from the ones dak is generating for all the cool kids).

So, 2) we can ignore for now, 1) would be nice to fix as basically everyone
has this one installed (and hence everyone has 2) installed), but "maybe" I
will leave that bugreport open for a while just to see what happens…


I know that everyone dreams about a stable API for a library, but I believe
that even an unstable library at this point is way better than the status
quo of having other layers like libapt (which is a proof that even if being
 unstable is a pain, the alternative would be worse – and that's a freaking
 C++ "library" …) providing makeshift replacements.

There are e.g. a bunch of dpkg-style version-comparison implementations in
Debian which should really just be a single one under the control of dpkg and
that might be "just" ~5 because libapt includes one, so it could be misused
by others (anyone remember the kernel depending on libapt-pkg-perl?).


Best regards

David Kalnischkies

P.S.: Could the table be enhanced with a description for the table headers?
I have no idea what an "ar slash" might be, and not really what LFS means
as the format has no support for >10 character filesizes as far as I know.