Bug#637231: Moving Digest::SHA to perl-base

[Niko Tyni]

On Tue, Aug 09, 2011 at 12:24:02AM +0200, Pino Toscano wrote:

> The short story is: we, Debian Hurd packagers, would like to see 
> Digest::SHA moved from "perl" to "perl-base".

As discussed in the policy (section 3.8, "Essential packages"), adding
functionality to the Essential set is not something to do lightly.
So I'd like to explore any alternatives first, particularly as this
is only needed on an unofficial architecture but would affect all the
installer footprint on official ones too.

> We are preparing to upload from debian-ports to Debian main a simple 
> Hurd translator, random-egd, to provide /dev/{,u}random devices. This 
> translator interfaces to a small init.d service written in Perl, a 
> slightly modified version of EGD (egd.pl). egd.pl uses sha1() from 
> Digest::SHA1 (which we changed to Digest::SHA, as Digest::SHA1 is 
> deprecated).
> The problem is that we need random-egd as dependency of the "hurd" 
> package (essential on hurd), so it must be essential too; although, 
> currently it cannot because Digest::SHA is in "perl", which is not an 
> essential package. Our proposal is whether you could move Digest::SHA 
> from "perl" to "perl-base".

Not all dependencies of essential packages need to be essential.
The requirement for staying usable even when unconfigured only applies
to the "core functionality" of the essential packages. I suppose
/dev/{,u}random needs to be regarded part of that?

Most essential packages declare Pre-Depends entries when their core
functionality does need non-essential packages (mainly libc*). However,
I doubt a Pre-Depends: perl would work in all scenarios involving system
upgrades.

I see /usr/bin/sha1sum is already in the Essential set. Would it
be viable to fork that and compute the SHA checksums through a pipe?
I expect performance is not a real issue here, given the choice of Perl
for such a low level daemon in the first place.
-- 
Niko Tyni   ntyni at debian.org