This calculates the difference between a set of layers and a
directory tree.
Upstream-commit: 60f552cac3d165dbe4c8d65c1ab82d31700dcc5d
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: ad402763e160ded1924c9b154983d81614e90deb
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: 727e7fcccadf1d3e286f5a3c8d1aa388f6b4dab8
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: 1c5dc26a7c0a0abb7bc59174768ec309f6c5fd4f
Component: engine
