This is especially interesting for the versioning symbols themselves,
as it is an indicator of when applications using introspection information
can start to use a symbol in the library to check if they have a
recent enough version of OSTree to use.
Closes: #932
Approved by: cgwalters
Actually trying to use this in rpm-ostree, it kept returning successfully when I
didn't expect it to... The first conditional was always succeeding even when I
was asking for a newer minor.
Closes: #766
Approved by: jlebon
OSTree currently provides no way to inspect the versioning
information at run time, being only available at compile
time through pkg-config.
This is a problem for e.g. Flatpak, that needs to check
whether the 'update-frequency' option is available. Checking
at compile time isn't great since it's not looking for new
symbols, but only if an optional feature is present.
This commit, then, adds a new header that is generated
at compile time, exposing OSTree's versioning information.
Closes: #728
Approved by: cgwalters