With the recent introduction of the RootNodes trait, there's nothing in
the fs module pulling in tvix-store dependencies, so it can live in
tvix-castore.
This allows other crates to make use of TvixStoreFS, without having to
pull in tvix-store.
For example, a tvix-build using a fuse mountpoint at /nix/store doesn't
need a PathInfoService to hold the root nodes that should be present,
but just a list.
tvix-store now has a pathinfoservice/fs module, which contains the
necessary glue logic to implement the RootNodes trait for a
PathInfoService.
To satisfy Rust orphan rules for trait implementations, we had to add a
small wrapper struct. It's mostly hidden away by the make_fs helper
function returning a TvixStoreFs.
It can't be entirely private, as its still leaking into the concrete
type of TvixStoreFS.
tvix-store still has `fuse` and `virtiofs` features, but they now simply
enable these features in the `tvix-castore` crate they depend on.
The tests for the fuse functionality stay in tvix-store for now, as
they populate the root nodes through a PathInfoService.
Once above mentioned "list of root nodes" implementation exists, we
might want to shuffle this around one more time.
Fixes b/341.
Change-Id: I989f664827a5a361b23b34368d242d10c157c756
Reviewed-on: https://cl.tvl.fyi/c/depot/+/10378
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
a5167c508c