var (
	DefaultDriver string
)

type Differ interface {
	Diff(id string) (archive.Archive, error)
	Changes(id string) ([]archive.Change, error)
	ApplyDiff(id string, diff archive.ArchiveReader) error
	DiffSize(id string) (bytes int64, err error)
}

type Driver interface {
	String() string

	Create(id, parent string) error
	Remove(id string) error

	Get(id, mountLabel string) (dir string, err error)
	Put(id string)
	Exists(id string) bool

	Status() [][2]string

	Cleanup() error
}

type InitFunc func(root string) (Driver, error)