Gentoo Archives: gentoo-alt

From: Fabian Groffen <grobian@g.o>
To: gentoo-alt@l.g.o
Subject: Re: [gentoo-alt] portage prefix chaining support
Date: Thu, 02 Apr 2009 20:23:01
Message-Id: 20090402202244.GA852@gentoo.org
In Reply to: Re: [gentoo-alt] portage prefix chaining support by Markus Duft
On 31-03-2009 09:41:17 +0200, Markus Duft wrote:
> On Tue, 2009-03-31 at 09:21 +0200, Fabian Groffen wrote: > > On 30-03-2009 14:03:04 +0200, Markus Duft wrote: > > > After looking at the heap of ruins my prefix-chaining was turned into in > > > just _one_ day (*grr* ;)), i'm just about to fix it again :) i'd say, we > > > could think about doing this unconditionally in [portage|portage > > > ebuild]. > > > > If you unconditionalise as patch, you'll find your patch removed when it > > breaks. I'm currently in Germany for work, so I can't guarantee I can > > look into it. > > ok. for the moment i'll leave it conditional for prefix-chaining then. > maybe we can look at it again when you're back.
I'm a bit concerned about the design of things here. Initially, we had "cross-prefix", where Portage's EPREFIX could be changed at runtime. This means Portage could "manage" another prefix, ideally meant to clone -- bootstrap using an existing Prefix from a location where you don't want to have it (read-only CD?). I don't know how far this actually got, but I know Portage does cross-prefix some things if you have EPREFIX set. For this EPREFIX became the *Target* Prefix, and BPREFIX became the *Build* Prefix, as in from the called Portage That means Portage will always look for stuff it works with (like bash, sed, etc.) from its own Prefix (BPREFIX), and just operate on stuff (vdb, install location, etc.) in its EPREFIX. Normally these two are the same. Now your chaining patches. Apparently you take the total opposite direction now, where you first have a Portage in EPREFIX (how you got it is questionable), and within this Portage you expect it to take stuff it works with (bash, sed) from a different location, let's call it CPREFIX. While this is a different approach, it just conflicts with the first approach, which is implemented and effectuated throughout the tree. I see your patches affecting multiple places where you revert our assumption that Portage should always take stuff from it's own Prefix. In short, I'm not happy with that. I keep asking myself, and now to you, why one would want to have a Portage instance that is crippled in the sense that it is not self-sufficient, and has to rely for the most critical things on "external" binaries. In other words, what was wrong with the initial approach of cross-prefix, which is very similar to how cross-compiling (with root) works? I don't want to kill all of your work, but I do want to make clear to you why I am so hesitant for all of your changes. Conceptually, I believe cross-prefix was sound and clear. Now this prefix-chaining is like a whole new world that seemingly has some dirty concepts that I find hard to accept. -- Fabian Groffen Gentoo on a different level

Replies

Subject Author
Re: [gentoo-alt] portage prefix chaining support Markus Duft <mduft@g.o>
Re: [gentoo-alt] portage prefix chaining support Michael Haubenwallner <haubi@g.o>