cdrtools - a tale of two licenses [LWN.net]

cdrtools - a tale of two licenses

Posted Aug 13, 2006 15:29 UTC (Sun) by ewan (subscriber, #5533) [Link]

No, however, in this case there is a build system, required to build the binaries, and permission to distribute the GPLed code in those binaries is only granted if the build system used to generate them is also licenced under the GPL.

Another piece of software may or may not have build scripts, they may or may not be Makefiles. All that matters to this discussion is that Jorg's cdrtools binaries require the CDDL build system to generate them. What hypothetical other projects do or consist of is of no relevance to cdrtools.

cdrtools - a tale of two licenses

Posted Aug 13, 2006 15:45 UTC (Sun) by dmantione (guest, #4640) [Link]

We're getting to the core of the matter. Schilling is claiming his build
system is independend. According to him there exists nothing in the GPL
part to build it.

As long as he can maintain that his build system is an independend work,
there is nothing in the GPL that forbids distributing binaries.

cdrtools - a tale of two licenses

Posted Aug 13, 2006 17:28 UTC (Sun) by ewan (subscriber, #5533) [Link]

No, he can't. The 'independence' or otherwise of the build system has nothing to do with it. You are still clinging to the 'derived work' idea.

Jorg's binaries are built with his CDDL build system. Jorg's binaries contain other people's GPL code. Jorg cannot distribute that code in his binaries without the permission of those other people. Those other people (by means of the GPL) give him the necessary permission if, and only if, the build system used to build the binaries is available under GPL compatible terms.

And it isn't.

The only way 'independence' of the two code bases would be sufficient division would be if Jorg had GPLed cdrtools, and a CDDL build system, and he did not use the latter to build the binaries of the former. As it stand the build system may well be independent of the cdrtools source - but it is not separate from the cdrtools binaries because they are built with it. The cdrtools source is also not indepentent of the CDDL build system if there is no other feasable way to build it.

cdrtools - a tale of two licenses

Posted Aug 13, 2006 19:55 UTC (Sun) by dmantione (guest, #4640) [Link]

Did the other people contribute Makefiles? Then he is not distributing
the other people their code without their Makefiles, and is not violating
their copyrights.

cdrtools - a tale of two licenses

Posted Aug 13, 2006 20:17 UTC (Sun) by k8to (subscriber, #15413) [Link]

The code of the other people present in the main work, that is cdrecord, mkisofs, is sufficient to keep it under the GPL as it was when they contributed the code.

The fact that the code is under GPL is sufficient to require that the Makefiles be placed under GPL for distribution of the code.

End of discussion.

cdrtools - a tale of two licenses

Posted Aug 13, 2006 20:30 UTC (Sun) by dmantione (guest, #4640) [Link]

No, of course not. If others haven't contributed source code including
Makefiles, they cannot claims those Makefiles are part of their source
code and enforce the GPL.

You guys are reading the GPL as "it is forbidden to distribute without
(GPL'ed) Makefiles", but it says "any Makefile is part of the source
code" which is there to prevent people circumventing the GPL by removing
all Makefiles from it.

But it is not really worth it to have a flame war over this as I don't
question that Schilling is playing games with the GPL... The guy hates
Linux and likes Solaris and is trying power tricks. I only fear that he
very well knows what he is doing :(

cdrtools - a tale of two licenses

Posted Aug 13, 2006 21:39 UTC (Sun) by k8to (subscriber, #15413) [Link]

My comments apply whether or not the Makefiles are part of the source. Where do you see that being mentioned in the quite simple argument?

The GPL says that it is forbidden to distribute without a similarly avilable build system.

cdrtools - a tale of two licenses

Posted Aug 14, 2006 13:42 UTC (Mon) by jond (subscriber, #37669) [Link]

"The GPL says that it is forbidden to distribute without a similarly avilable build system.".

Which GPL, and which clause? I've just read GPL-2 in its entirety and could find no such clause or anything similar.

cdrtools - a tale of two licenses

Posted Aug 14, 2006 15:57 UTC (Mon) by bfields (subscriber, #19510) [Link]

Section 3 of GPL v2 contains the requirement that you must make the source code available for binaries that you distribute, and says that "The source code for a work means the preferred form of the work for making modifications to it. For an executable work, complete source code means all the source code for all modules it contains, plus any associated interface definition files, plus the scripts used to control compilation and installation of the executable."

It doesn't matter whether or not the "scripts used to control compilation" are a derived work of somebody else's code or not. What matters is if the built executable is a derived work of that code. If so, then you need the copyright holders' permission to distribute the executable. If the only permission they've given you is the GPL'd code, then they've told you "fine, you can distribute compiled binaries derived from this, but only if you also distribute your makefiles." And they're perfectly within their rights to do that.

cdrtools - a tale of two licenses

Posted Aug 13, 2006 20:42 UTC (Sun) by ewan (subscriber, #5533) [Link]

No, they contributed code to the main body of the program. They did so
under the GPL, which requires the build scripts to be made available
under the same terms. Unless the distributor complies with that condition
the permission to distribute the covered work is taken away.

You're still hanging onto this idea that the only thing that counts is
copyright law itself, and that the terms of the licence mean nothing. The
point of copyright in this situation is to say that you can't distribute
someone else's work without their permission. It has nothing to say about
what you have to do to get their permission. In this case you have to
distribute the build system under the same terms, or you don't get their
permission.

It really is that simple.

cdrtools - a tale of two licenses

Posted Aug 13, 2006 20:52 UTC (Sun) by dmantione (guest, #4640) [Link]

Ok, my last attempt to make it clear.

Let's say I contribute a patch. I put the patch under GPL and give it to
you.

You now have permission to distribute it. But my patch does not contain a
Makefile. So, *my* source (the part I own copyright) does not contain a
Makefile.

So, if you distribute binaries and source, you are distributing the code
*I* own. But *I* did not include anything to build it, so I cannot force
you write such a build tool. There was no Makefile in my source, so I
cannot enforce the GPL onto you to distribute such a Makefile.

cdrtools - a tale of two licenses

Posted Aug 13, 2006 21:33 UTC (Sun) by ewan (subscriber, #5533) [Link]

Yes, you can, if the total work that your code is included in requires
such a Makefile to build. If I include your code in a project with no
Makefile, then I'm OK, if I include it in a project that relies on a
Makefile, then that Makefile must be GPLed, as must everything else that
makes up the project.

You can't force me to add anything to your code, or make any
modifications to it at all, however, if I chose to do so then you can
force me to make those additions or modifications available under the GPL
(assuming of course that I'm distributing it).

Look at it from the point of view of an end user receiving the binary -
because of the GPL licence they have the right to modify the program.
They cannot do that if they cannot build their modified source because
they don't have the Makefile.

cdrtools - a tale of two licenses

Posted Aug 13, 2006 22:03 UTC (Sun) by HenrikH (guest, #31152) [Link]

But still the whole source is put under the GPL and since there is no added clause that sais that the makefile requirement is void, the requirement is still there in the license.

If you send a patch under the GPL to this project without having written a makefile for your patch in question changes nothing since you still only give the distributor the rights to distribute your patch if he follows the GPL requirements (that is including the makefiles used to build the binary), if the distributer chooses not to include the makefiles in a GPL compatible way, then he has no rights to distribute your patch and he has to remove it from the source in order to be able to distribute the binary!

You still seam to think that this has something to do with the "viral"-propery of the GPL, but as others already has pointed out on several occasions there is nothing here that makes the makefiles automatically become GPLed.

Instead the thing is that the only thing that is allowing you to distribute the cdrtools binary is the GPL, and since the GPL requires you to also distribute the makefiles used to build the binary you have to do so or lose the rights to distribute the binary.

If you somehow can manage to build the cdrtools binary without the makefiles then you are of course free to distribute the resulting binary without the makefiles since you didn't use them in order to build it.

cdrtools - a tale of two licenses

Posted Aug 14, 2006 16:12 UTC (Mon) by bfields (subscriber, #19510) [Link]

"Ok, my last attempt to make it clear."

Oh, you're clear enough; it's just that you're also wrong:

"Let's say I contribute a patch. I put the patch under GPL and give it to
you.

"You now have permission to distribute it."

Assuming the patch is nontrivial, I only have permission to distribute it if I meet the requirements of the GPL.

"But my patch does not contain a Makefile. So, *my* source (the part I own copyright) does not contain a Makefile."

That's correct. In particular, the Makefile is not automatically covered by the GPL.

"So, if you distribute binaries and source, you are distributing the code
*I* own. But *I* did not include anything to build it, so I cannot force
you write such a build tool."

If I distribute binaries, presumably I built them somehow. Since the binaries are now a derived work of your patch, I am required to get your permission before I can distribute the binaries. By giving me the patch only under the GPL, you've said that you only give your permission if I also tell people how to build those binaries. So I'm required to give out any makefiles I used, regardless of whether those makefiles are a derived work or not.

There's nothing in copyright law to prevent you from making a requirement like that, even though that requirement in part affects the distribution of a work you didn't write yourself. People need your permission to distribute your code, so you can make them do pretty arbitrary things to get that permission.

cdrtools - a tale of two licenses

Posted Aug 14, 2006 12:55 UTC (Mon) by dwmw2 (subscriber, #2063) [Link]

" As long as he can maintain that his build system is an independend work, there is nothing in the GPL that forbids distributing binaries."

If identifiable sections of that work are not derived from the [GPL'd parts], and can be reasonably considered independent and separate works in themselves, then [the GPL], and its terms, do not apply to those sections when you distribute them as separate works.

But when you distribute the same sections as part of a whole which is a work based on [the GPL parts], the distribution of the whole must be on the terms of [the GPL], whose permissions for other licensees extend to the entire whole, and thus to each and every part regardless of who wrote it.

(GPL, section 2)

One cannot sensibly argue that the combination of build scripts with the source code that they build is 'mere aggregation on a volume of a storage or distribution medium'. It is a collective work, and the GPL applies to all parts of it -- even those parts which would be considered independent and separate works if distributed on their own.