This fixes the case where directory is removed in
aufs and then the same layer is imported to a
different graphdriver.
Currently when you do `rm -rf /foo && mkdir /foo`
in a layer in aufs the files under `foo` would
only be be hidden on aufs.
The problems with this fix:
1) When a new diff is recreated from non-aufs driver
the `opq` files would not be there. This should not
mean layer differences for the user but still
different content in the tar (one would have one
`opq` file, the others would have `.wh.*` for every
file inside that folder). This difference also only
happens if the tar-split file isn’t stored for the
layer.
2) New files that have the filenames before `.wh..wh..opq`
when they are sorted do not get picked up by non-aufs
graphdrivers. Fixing this would require a bigger
refactoring that is planned in the future.
Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>
Upstream-commit: 00e3277107a63218b656a36457caf380f9cabf37
Component: engine
cd1e105d78