RFR: more FC4 Requests

[Panu Matilainen]

On Sat, 2004-11-20 at 19:36 -0500, Jeff Johnson wrote:
> Panu Matilainen wrote:
> 
> >
> >For Extras it's irrelevant but I think JBJ was talking about adding apt-
> >rpm to Core.
> >
> 
> I was talking about adding to FC4, and there still appears to be 
> interest, although perhaps in passing,
> considering the irony that I am suggesting adding apt-rpm to FC4 and you 
> are suggesting unnecessary ;-)
> 
> Implementing multilib in a depsolver is not that hard, one needs to 
> check Provides: and Requires:
> color, and match iff the same color for each (or no color, that is the 
> traditional rpm behavior). There were
> perhaps 10 places that required about 5 lines of code in rpmlib to make 
> that happen. The harder problem
> was attaching dependencies to files that carry a elf32/elf64 color, but 
> that is not an apt-rpm issue.

It's a nontrivial problem because of apt-rpm internal presentation of
packages and their dependencies. 64bit vs 32bit packages are not an
issue, the problem is specifically packages with identical name-
(epoch:)version-release) which is something apt's internals do not
handle well. Can be kinda worked around but it's hideously ugly stuff.

> 
> There are a number of cheats to use repomd data only during initial 
> package discovery, just like yum itself
> is doing. Alas, a Header is still the only ticket that 
> rpmtsAddInstallElement() will punch for a ride through
> rpmlib, so yum is pulling the header using a HTTP GET with byte-range 
> from the package, and the xml
> metadata is used to determine which headers (and packages) need to be 
> pulled. Similar things could
> be done for apt-rpm.

Well apt doesn't need the headers at all since it resolves the deps by
itself and only uses rpmtsAddInstallElement() when preparing the real
transaction. Adding the new repodata support to apt-rpm wouldn't be
rocket science, it just needs somebody to put some effort into it and I
find myself currently lacking the enthusiasm to do that.

> 
> But I'm not at all sure how and when lack of multilib and repo-md 
> support became critical deficiencies
> for depsolvers. There are many who love apt still, Fink on Mac OSX comes 
> to mind.

Sure, people love and use it (for example the Lua-interface is a killer
feature which yum currently lacks) but it's starting to seem like a dead
end to me.

	- Panu -