[Mageia-dev] About panotools patent problem (and other problematic rpms)

Sat Feb 19 20:27:29 CET 2011

2011/2/18 Michael Scherer <misc at zarb.org>:
+> Le vendredi 18 février 2011 à 12:47 +0000, James Kerr a écrit :
+>
+>> If there are two packages, one in core and another in tainted, then
+>> doesn't urpmi need a way to recognise that the tainted package is newer
+>> than (an update to) the corresponding core package? I believe that this
+>> is achieved in Mandriva, because plf is greater than mdv.
+>
+> That's abusing release tag and it work by pure chance ( ie, had the plf
+> decided to  be called the guillomovitch liberation front, it would not
+> have worked ). And this is quite inflexible, since people will always
+> have plf packages, leading to users adding some rpm in skip.list with a
+> regexp.
+Exactly! :)
+
+I've just started to look into implementing support for favoring packages
+based on %disttag, I'm thinking about implementing it in a way similar to this:
+
+Say we have global variables such as these in urpmi.cfg:
+
+disttag-priority: plf,mdv,mga
+disttag-pin: 1
+disttag-pin-force: 0
+
+in urpmi:
+
+* if disttag-priority is defined, it will compared the disttag of all
+packages that
+has the same or newer version, and favor the one of those with the disttag
+that's highest on the disttag-priority list.
+
+* if disttag-pin is set, it will refuse to upgrade to a newer version
+of a package
+that has a different disttag than the one installed.
+
+* if disttag-pin-force is set, it will *always* upgrade/downgrade to the newest
+version of a package which has the highest priority match, ie. if foo-2-1mdv
+is installed, and the newest version with 'mga' disttag available in repos is
+foo-1-1mga, then it will downgrade to it.
+
+Notice that %disttag is a tag that's been implemented in rpm since long time
+ago, but was never really adopted for anything, so in rpm5 it was dusted off
+and was adjusted a tiny bit for it to be made possible to be defined globally
+through macro files read, similar to ie. %vendor etc.
+
+I've already in the past patched rpm 4.6 in cooker with support for at least
+recognizing %distepoch (but not for using it in version comparision, doing
+it should be fairly trivial though), I might've already made the change
+mentioned for %disttag as well in the same patch, I don't really remember,
+should anyhow be very trivial to do..
+
+So if you'd like to eliminate 'mga' from release and version comparision,
+you can already do so by making the minor change for %disttag, then
+make adjustments accordingly to %_build_name_fmt and %mkrel.
+
+Adopting distepoch as well will require slightly more, but won't really been
+hard (the hard part has already been tendered well after slamming cooker
+a bit more than expected..;) and would be a sane thing to adopt anyways..
+
+FWIW in .spec files, the preferred conditional would be:
+
+%if "%disttag" == "mga"
+blabla
+%else if "%disttag" == "plf"
+hubbabubba
+%else if "%disttag" == "mdv"
+boink!
+%endif
+
+WDYT?
+
+--
+Regards,
+Per Øyvind
+