Missing license

[mikegerwitz]

The project doesn't appear to have a license. Since libpurple is GPLv2+, my assumption is that this project intends to adopt that same license (GPLv3+ would be a bonus!).

You can do so by adding a file named COPYING (some use LICENSE) containing the text of the version of the GPL you wish to use. The recommended way of conveying "or later" is to place a copyright header at the top of each source file containing the appropriate cause, just as the files in /headers/jabber do.

See the section "How to Apply These Terms to Your New Programs" here:

https://www.gnu.org/licenses/gpl.html

In any case, thank you for writing free software!

[gkdr]

To be honest, I evaded the license question because I don't know much about them, but maybe you can help me out.
Since I link libsignal - which is licensed under GPLv3 - statically into this plugin, does my code also necessarily need to be GPLv3, or is GPLv2+ also possible?
If this plugin needs to be GPLv3, does ALL code that gets statically linked into this plugin need to be GPLv3, i.e. the code I exported into separate projects and now use as submodules? Or is that not the case because this plugin imports them, and not the other way round?

[mikegerwitz]

but maybe you can help me out.

Certainly!

Since I link libsignal - which is licensed under GPLv3 - statically into this plugin, does my code also necessarily need to be GPLv3, or is GPLv2+ also possible?

Sorry, I didn't look too deeply before making my comment. Since libsignal is GPLv3, you are correct that GPLv2 is not an option. Unfortunately, since libsignal does not have an or-later clause, you can only do GPLv3, not GPLv3+.

does ALL code that gets statically linked into this plugin need to be GPLv3, i.e. the code I exported into separate projects and now use as submodules?

Any project that links against a GPL'd program must itself be licensed under a compatible license (GPLv3 in this case). Some projects offer linking exceptions (or use the LGPL), but you don't have that option since both libpurple and libsignal would have to allow such an exception. libsignal provides an exception for the App Store, but since libpurple doesn't, you can't exercise it.

Or is that not the case because this plugin imports them, and not the other way round?

lurch can use any code or link against any software that is compatible with the GPL. The combined work (lurch) would be licensed under the GPLv3.

[gkdr]

Thanks for the clarification! Now that I know what to do, I'm going to implement it soon.