Re: gitoxide-compatible licensing of Git's Rust code, was Re: [PATCH 6/7] xdiff: conditionally use Rust's implementation of xxhash

From: Phillip Wood <phillip.wood123@gmail.com>
Date: Sep 26, 2025, 10:06 UTC
Message-ID: <20140030-6bf1-4393-a941-bfdbc69c79fb@gmail.com>
In-Reply-To: <20250925022555.GA3202669@coredump.intra.peff.net>

On 25/09/2025 03:25, Jeff King wrote:

Show 15 quoted lines

> On Wed, Sep 24, 2025 at 02:48:26PM +0100, Phillip Wood wrote:
> 
>> Thanks for putting this so clearly, I agree with everything that you've
>> written here. Another thing I'm concerned/confused about is how the
>> exception for a single project works in practice. Does it mean that a third
>> party that wants to re-use some code from GitOxide has to check if the code
>> originally came from Git to determine which license it is under? Or does it
>> mean that anyone who wants to use Git's code without the copyleft
>> restrictions can do so if they launder it through GitOxide first? Neither of
>> those seems like a great outcome.
> 
> If I understand the suggestion correctly, it's not to license it
> specifically to GitOxide. It's to use a permissive license (like GPL
> with linking exception) that would make it compatible with other
> projects with similar licenses (like GitOxide).

I was responding to this paragraph in Johannes' message

     Note the exception? For new Rust code (and of course excluding code
     that has been ported verbatim from GPLv2-licensed code), GPL v2
     could be used with an exception along these lines: This file is
     licensed under the GPL v2, with the exception that it can be freely
     used in the Gitoxide project.

That suggestion is pretty close to what libgit2 has in its git.git-authors file[1]. I'm not sure how practical it is to special case just one project though.

Thanks

Phillip

[1] https://github.com/libgit2/libgit2/blob/main/git.git-authors