This commit adds meson build support to mutter. It takes a step away
from the three separate code bases with three different autotools setups
into a single meson build system. There are still places that can be
unified better, for example by removing various "config.h" style files
from cogl and clutter, centralizing debug C flags and other configurable
macros, and similar artifacts that are there only because they were once
separate code bases.
There are some differences between the autotools setup and the new
meson. Here are a few:
The meson setup doesn't generate wrapper scripts for various cogl and
clutter test cases. What these tests did was more or less generate a
tiny script that called an executable with a test name as the argument.
To run particular tests, just run the test executable with the name of
the test as the argument.
The meson setup doesn't install test files anymore. The autotools test
suite was designed towards working with installed tests, but it didn't
really still, and now with meson, it doesn't install anything at all,
but instead makes sure that everything runs with the uninstalled input
files, binaries and libraries when running the test suite. Installable
tests may come later.
Tests from cogl, clutter and mutter are run on 'meson test'. In
autotools, only cogl and clutter tests were run on 'make check'.
In order to minimize the amount of breakage, while at the same time
making it easier to make backward incompatible changes needed to
continue turning libmutter into a capable Wayland compositor, make the
libmutter and friends (libmutter-clutter, libmutter-cogl*) parallel
installable by adding a version number to the name. This changes
various filenames, for example what previously was libmutter.so is now
libmutter-0.so (assuming the version for now is 0), and
libmutter-clutter-1.0.so is now libmutter-clutter-0.so. The pkg-config
filenames and GObject introspection has been renamed to reflect this as
well.
This enables a downstream compositor rely on a specific version of the
libmutter API, while gracefully handling API/ABI changes by having to
update to the new version at their own pace.
https://bugzilla.gnome.org/show_bug.cgi?id=777317
