This file is available in a flatpak sandbox and will contain various
info such as the build commit, very useful info as we can have several
builds for a same version. For instance if we have exactly the right
commit, we can load exactly the same binary as a bug reporter very
easily, hence are able to get source correspondance without necessarily
asking reporters to install debug symbols (though it stays easier if
they can do it).
Other interesting info contained in this file are the exact runtime
used, the installed application or runtime extensions, the permissions
(people may override our flatpak permissions so it's useful to be able
to check when they did) and environment variables…
I didn't realize it because the meson build was returning 'windows' for
GIMP_BUILD_PLATFORM when I cross-built with Mingw-w64. But in the
autotools, it was storing "mingw32", which would not compare with our
gimp_versions.json. Therefore in GIMP 2.10.16, the version update check
would have worked, but not the revision check.
This fixes the problem.
I realized having the revision as a build number is the wrong idea as it
implies packagers will have to rebuild GIMP for just a revision. Yet
very often revision may just be data change or dependency fix/update
without rebuild needed (i.e. no ABI change).
Instead let's keep this package information as a file 'gimp-release'
(inspired by /etc/os-release and other /etc/*-release files of
distributions).
The idea is to be able to advertize a new revision of the same version
of GIMP. For instance, this would apply when we release a
`gimp-2-10-14-setup-3.exe` Windows installer (then we are at revision
3, provided we started at revision 0).
The revision number is obviously only relevant to a given platform and
version. Also the concept of build ID allows to differentiate various
builds for a same platform, in particular to not look at revisions of
third-party builds. The build ID can be any string. Maybe we could just
use reverse DNS build id (such as "org.gimp.GIMP_official") to identify
the official GIMP build. So in the end, we only compare revisions for an
identical (version, platform, build-id) tuple.
The point will be for a packager to create a unique build ID to identify
the build or provenance. I also add a revision number so that we can
identify 2 builds from the same version/commit, same maker and platform.
It will also be used later to check for new versions (see "phone home"
feature #2584).
Separating autotools and meson commits for easy backport.
Since commit 9fdf35550b, I removed the GIMP_APP_GLUE_COMPILATION check
because we need to have the whole versioning info from the new debug
widget. It just makes sense to go further and just make this a proper
internal API to get version information.
Jehan