Bug#687255: apt_preferences(5) support for pinning by architecture
On Tue, Sep 11, 2012 at 04:13:15PM +0800, Daniel Hartwig wrote:
> Package: apt
> Version: 0.9.7.4
> Severity: normal
> Tags: patch
>
> Moving the discussion about pinning by architecture to a new report.
> Original context is <http://bugs.debian.org/670322>
>
> On 11 September 2012 09:18, Daniel Hartwig <mandyke@gmail.com> wrote:
> >> Arch-qualification will work for specific-packages stanzas only,
> >
> > A bit of a hack but it worked when I tested it. apt-cache policy
> > listed every armel package as pinned, which is not very nice output
> > ;-)
>
> Looks like I misread and thought you were saying that doesn't work.
> Sorry for that :-)
>
> >
> >> but you can do this:
> >> Package: *
> >> Pin: release n=squeeze,b=armel
> >> Pin-Priority: 991
> >
> > A better format, though it is not documented or working (?) in 0.9.7.4:
>
> I see where the support for this is in versionmatch.cc and the above
> seems to not work because PackageFile::Architecture is never
> populated. Actually, python-apt docs say this is normal:
>
> > class apt_pkg.PackageFile
> > …
> > architecture
> > The architecture of the package file. This attribute normally
> > contains an empty string and is thus not very useful.
>
> Is there a reason for that (maybe to do with arch: all)? Looks like
> it could be done in debListParser::LoadReleaseInfo (or
> debPackagesIndex::Merge).
You can only have those for Debian-style repositories with
dists/, you can not have this for flat repositories.
>
> I have attached a first attempt at a patch, which partially works
> (obviously needs more testing).
>
> Note that the candidate for aptitude /seems/ wrong, but technically
> the first stanza (“Package: *”) does not apply since the second is
> more specific. Changing the second to “Package: aptitude:amd64” gives
> better output but defeats the purpose of using “b=amd64”, at least on
> specific-package stanzas.
It does not work, probably because APT tries to pin aptitude:i386 to
a version with architecture: amd64, which does not exist. I'd go
with EXPRESSION:ARCHITECTURE pinning, like aptitude:amd64 or *:amd64,
or /regex/:amd64. But we don't appear to have implemented *:amd64
correctly yet (with the same semantics as *, it is not considered
more generic than name:amd64). I don't know whether this is possible
though.
--
Julian Andres Klode - Debian Developer, Ubuntu Member
See http://wiki.debian.org/JulianAndresKlode and http://jak-linux.org/.
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