Relicense X11 as LGPL

[KamilSucharski]

This issue is closed, but as of today, I still see 17 code files still under GPL. I would especially appreciate if something could be done with X11, since it's only these 3 files: x11_common.h, x11_common.c and vo_x11.c.

The X11 itself doesn't seem to be GPL licensed, nor does Xlib. Is there some other legal blocker I don't see here, or is it just a matter of someone submitting a pull request that rewrites these 3 files in LGPL and allows the compilation with --gpl=false?

[Dudemanguy]

The only semi-realistic way to do this would be to write an xcb backend from scratch as lgpl but I don't see any reason to invest time in that. vo_x11 would still be GPL of course. Nothing can really be done about that.

[KamilSucharski]

Nothing can really be done about that.

@Dudemanguy Could you explain why? I'm trying to understand where exactly the GPL blockers exist - the code in these 3 files, or some external dependency?

[Dudemanguy]

Suggesting to rewrite an entire backend that is probably like 20 years old (or whatever the number is) is pretty much a non-starter. It's not going to happen.

[philipl]

X11 support will be completely irrelevant before someone works up the motivation to write a clean-room backend.

And it's also not clear what real world relevance this would have - the way you'd be integrating mpv with other code is via libmpv, and I want to say that your app can use X11 without there being any of this X11 code in libmpv. Certainly we'll have working vulkan interop in libmpv before an X11 rewrite.

[KamilSucharski]

We prefer to not allow using mpv source for free in proprietary projects.

It sounds a bit contradictory to the license, as most of mpv is under LGPL, so if another project is LGPL-compliant (provides source of the mpv code that was compiled, links to it dynamically, allows relinking etc.), all should be well and good.

Why do you want to make it LGPL?

My use case is bundling a minimal custom compilation of libmpv in my non-GPL project (which isn't a video player, but needs a video preview), and embedding in X11 using --wid. It's leaner and simpler than telling users to download mpv themselves.

[avih]

It sounds a bit contradictory to the license

It does, and it is. At the time the license was changed from GPL to LGPL which was led by the main developer at the time, and most other devs went along, not because they strictly wanted LGPL, but because the leader had enough pull to make it happen.

If this happened today, most devs would probably prefer to keep it GPL.

My use case is bundling a minimal custom compilation of libmpv in my non-GPL project

May I ask which license it has?

[KamilSucharski]

your app can use X11 without there being any of this X11 code in libmpv

Hmm, I haven't had success in getting it to work on X11. It wouldn't surprise me if the set of flags I used during compilation was missing something... I have these two logs, one from my compilation (faulty) and one from the official arch repo (working). If you could take a quick look and tell me where I possibly made some dumb mistake, I would be grateful.
mpv-x11-official-working.log
mpv-x11-custom-faulty.log