Subject: Re: What licenses should be included in /usr/share/common-licenses?

From: Russ Allbery <[email-masked]>
Date: Sun, 10 Sep 2023 09:00:22 -0700

Jonas Smedegaard <[email-masked]> writes:
> Quoting Hideki Yamane (2023-09-10 11:00:07)

>>  Hmm, how about providing license-common package and that depends on
>>  "license-common-list", and ISO image provides both, then? It would be
>>  no regressions.

I do wonder why we've never done this.  Does anyone know?  common-licenses
is in an essential package so it doesn't require a dependency and is
always present, and we've leaned on that in the past in justifying not
including those licenses in the binary packages themselves, but I'm not
sure why a package dependency wouldn't be legally equivalent.  We allow
symlinking the /usr/share/doc directory in some cases where there is a
dependency, so we don't strictly require every binary package have a
copyright file.

>>  I expect license-common-list data as below
>> 
>>  license-short-name: URL
>>  GPL-2: file:///usr/share/common-licenses/GPL-2
>>  Boost-1.0: https://spdx.org/licenses/BSL-1.0.html

> Ah, so what you propose is to use file URIs.

> I guess Russ' response above was a concern over using http(s) URIs
> towards a non-local resource.

Yes, I think the https URL is an essential part of the first proposal,
since it avoids needing to ship a copy of all of the licenses.  But I'm
dubious that would pass legal muster.

The alternative proposal as I understand it would be to haave a
license-common package that includes full copies of all the licenses with
some more relaxed threshold requirement and have packages that use one of
those licenses depend on that package.  (This would obviously require a
maintainer be found for the license-common package.)

> License: Apache-2.0
> Reference: /usr/share/common-licenses/Apache-2.0

This is separate from this particular bug, but I would love to see the
pointer to common-licenses turned into a formal field of this type in the
copyright format, rather than being an ad hoc comment.

-- 
Russ Allbery ([email-masked])              <https://www.eyrie.org/~eagle/>