This calculates the difference between a set of layers and a
directory tree.
Upstream-commit: ad0a6a03e3595aa04cf731cf17e90be87163389a
Component: engine
Change the comparison to better handle files that are copied during
container creation but not actually changed:
* Inode - this will change during a copy
* ctime - this will change during a copy (as we can't set it back)
* blocksize - this will change for sparse files during copy
* size for directories - this can change anytime but doesn't
necessarily reflect an actual contents change
* Compare mtimes at microsecond precision (as this is what utimes has)
Upstream-commit: 36603e68e33dd5ab5c317c181e023f7ef7356434
Component: engine
Rather than scan the files in the old directory twice to detect the
deletions we now scan both directories twice and then do all the
diffing on the in-memory structure.
This is more efficient, but it also lets us diff more complex things
later that are not exact on-disk trees.
Upstream-commit: 02b5f1369ce09d597336e77df98e56d467b8d1ff
Component: engine
To do diffing we just compare file metadata, so this relies
on things like size and mtime/ctime to catch any changes.
Its *possible* to trick this by updating a file without
changing the size and setting back the mtime/ctime, but
that seems pretty unlikely to happen in reality, and lets
us avoid comparing the actual file data.
Upstream-commit: 8e8ef7cb5b208ac657af812ebc5ffa783664cf3b
Component: engine
