Lots and lots of preparation led to this moment - when nothing
apparent changes for users! Woo!
But seriously, having the extra dependency is a minor annoyance, and
in the big picture I think the libgsystem idea was wrong - we need to
land things in GLib, and use git submodules for API-unstable or
Linux-specific sharing. For a lot of OSTree, the libgsystem `GFile*`
orientation was also wrong, we really want fd-relative.
Closes: #444
Approved by: jlebon
This kills another GSystem consumer...I think down the line I'd like
to do something like "detect whether file is > 1k if so, mmap,
otherwise just readall()" so we can use this helper in more places.
Closes: #319
Approved by: jlebon
⚠️ There is a notable spiked pit trap here around
`posix_fallocate()` and `errno`. This has bit other projects,
see e.g.
7bb87460e6
Otherwise the port was straightforward.
An OSTree user noticed that `ostree fsck` would produce `missing
object` errors in the case of interrupted pulls.
It's possible to do e.g. `ostree pull --subpath=/usr/share/rpm ...`,
which gets you just that portion of the commit. The use case for this
was being able to see what changes would appear in an update before
actually downloading all of it.
(I think this would be better covered by static deltas, but those
aren't final yet, and `--subpath` predates it)
Further, `.commitpartial` is used as a successor to the `transaction`
symlink for more precise knowledge in the case where a pull was
interrupted that we needed to resume scanning.
So it makes sense for `ostree fsck` to be aware of it.
This is just an efficiency optimization. We're getting fairly close
to all of the hot code paths using `*at()`.
Note that we end up maintaining a half-duplicate code path set here,
because we still need to support commits from an arbitrary GFile *,
which in a possible common case is an OSTree commit.
I think it's worth it though.
Colin Walters
Giuseppe Scrivano
Matthew Barnes
Daniel Svensson
Alexander Larsson