Replace build system with meson

[MathieuDuponchelle]

Meson is a fast, user-friendly build system, and many projects have already adopted it as a replacement for autotools.

This port has only been tested on Linux for now, I believe it should build fine on Windows / Mac but haven't tested these platforms so take it with a grain of salt.

I hope this is a welcome proposal :)

[MathieuDuponchelle]

If that is of interest, meson is fairly easy to hook up with CI tools such as travis: https://mesonbuild.com/Continuous-Integration.html

[jbkempf]

I disagree on having an alternative build system: you should replace it completely.

Please follow the conventions we use on dav1d, for the meson file, though. Including proper licensing, warning levels, windows_flags and version_api +abi numbering

[MathieuDuponchelle]

I disagree on having an alternative build system: you should replace it completely.

Fair enough, however I wouldn't feel comfortable proposing a patch doing that without testing on all the target platforms, and that's a larger time commitment than I'm ready to make right now :)

Please follow the conventions we use on dav1d, for the meson file, though. Including proper licensing, warning levels, windows_flags and version_api +abi numbering

I'll take a look, though it would be more helpful if you could make specific comments inline instead of asking me to infer conventions from a seemingly-unrelated project's build system ;)

[tguillem]

Fair enough, however I wouldn't feel comfortable proposing a patch doing that without testing on all the target platforms, and that's a larger time commitment than I'm ready to make right now :)

You can still propose a patch and we will test it on all platforms.

[jbkempf]

I agree: we will test it.

[MathieuDuponchelle]

There you go, removed autotools, took as much inspiration as I could from the dav1d build system, but some things you asked were not applicable (eg the previous build system didn't use a soname). Hope that's useful.

[ePirat]

Thanks a lot for your work on this! I did a quick review and noted some things inline.

[jbkempf]

the previous build system didn't use a soname

Of course it did, but it was set to 0, which is OK for a new library.

Hope that's useful

It is, Thanks very much.

[jbkempf]

Anyway, this looks very nice, and in the right direction.

[MathieuDuponchelle]

Of course it did, but it was set to 0, which is OK for a new library.

hrm sorry got confused with so version for a second here (that was in answer to your ABI numbering request) :)

[ePirat]

It seems there is still no (so)version set for the library.

cc @jbkempf

Unfortunately there is a little gotcha, libtool versioning works different from what one would expect so with version 0:0:0 on macOS you end up with:

libfoo.0.dylib (compatibility version 1.0.0, current version 1.0.0)

This is extremely confusing as the version in the file name does not match the compatibility version or current version…

With meson setting a version of 0.0.0 like so:

library('foo',
    files('libfoo.c'),
    install: true,
    build_by_default: true,
    version: '0.0.0'
)

results in

libfoo.0.dylib (compatibility version 0.0.0, current version 0.0.0)

as one might expect.

Of course this means that when we now set version 0.0.0 in meson, the filename will match with autotools-built versions but the actual version information will be different…
If this problem is limited to macOS though, we can ignore it, as there are probably not many users of microdns on macOS.

[jbkempf]

I don't think we care, for now, tbh.

[MathieuDuponchelle]

Is there anything more I can do to help this go ahead, or is it simply a matter of someone finding time to test on the relevant platforms? I'll be testing this on a Windows (10) later, what other platforms will require testing?

[MathieuDuponchelle]

Had to patch a few things here and there, but my branch now builds with MSVC, and both executables work just fine :)

Side note: I needed ping mdnshost.local to work as well, and the most straightforward I could find was to install Bonjour Print Services from https://support.apple.com/kb/dl999?locale=en_US , do you guys have a less weird recommendation to make?

[ePirat]

Can we maybe split MSVC support into a new PR?

[ePirat]

I don't think we should mix these two things into one discussion…

[MathieuDuponchelle]

@ePirat no problem, though I'll propose things sequentially then. Removed my MSVC changes from the branch.

[MathieuDuponchelle]

I've also tested with msys2 mingw64, the current state of the branch builds just fine there

[jbkempf]

LGTM. To me, this is good enough to merge, for now.

[MathieuDuponchelle]

So, someone care to press the green button ? :)

[MathieuDuponchelle]

Had forgotten to set install: true on the targets we want installed

[MathieuDuponchelle]

ping :)

[ePirat]

Why did you add an uninstalled pc file? Did we have one before? It doesn't seem so.

[ePirat]

Additionally meson has no support for uninstalled pc files yet (afaik) using the proper module so I would prefer to not add one before meson supports that.

And personally I do not see the need for the uninstalled pc file variant.

[MathieuDuponchelle]

Why did you add an uninstalled pc file? Did we have one before? It doesn't seem so.

There was no uninstalled PC file before no, but it's a nice practice. I don't depend on it anyway

[MathieuDuponchelle]

@ePirat , removed, don't think this is worth an argument :) There's one other sore point however which I'd like to solve to be able to use libmicrodns as a subproject: renaming the src directory to microdns. That way the examples and external users will include microdns.h the same way, with a microdns/ prefix. Do you reckon this can make it into the MR? This point is very much related to the meson port IMHO

[MathieuDuponchelle]

ping :)

[ePirat]

🎉

[MathieuDuponchelle]

whee!