This wraps a few common steps. It is defined as inline function instead of in a
.c file to avoid having a .c file. With a .c file, we would have three choices:
- either link it into libshared, but then then libshared would have to be
linked to libmount.
- or compile the .c file into each target separately. This has the disdvantage
that configuration of every target has to be updated and stuff will be compiled
multiple times anyway, which is not too different from keeping this in the
header file.
- or create a new convenience library just for this. This also has the disadvantage
that the every target would have to be updated, and a separate library for a
10 line function seems overkill.
By keeping everything in a header file, we compile this a few times, but
otherwise it's the least painful option. The compiler can optimize most of the
function away, because it knows if 'source' is set or not.
It seems better to use just a single parsing algorithm for /proc/self/mountinfo.
Also, unify the naming of variables in all places that use mnt_table_next_fs().
It makes it easier to compare the different call sites.
Use a trivial header file to share mnt_free_tablep and mnt_free_iterp.
It would be nicer put this in mount-util.h, but libmount.h is not in the
default include path, and the build system would have to be adjusted to pass
pkg-config include path in various places, and it's just not worth the trouble.
A separate header file works nicely.
Let's move the shutdown binary into its own subdirectory in
src/shutdown, after all it is relatively isolated from the normal PID 1
sources, being a different binary and all.
Unfortunately it's not possible to move some of the code, since it is
shared with PID 1, that I wished we could move, but I still think it's
worth it.