// NewDirectoryLayer returns a new root directory (as a Directory). The
// subspaces nodeSS and contentSS control where the directory metadata and
// contents are stored. The default root directory has a nodeSS of
// subspace.FromBytes([]byte{0xFE}) and a contentSS of
// subspace.AllKeys(). Specifying more restrictive values for nodeSS and
// contentSS will allow using the directory layer alongside other content in a
// database.
//
// If allowManualPrefixes is false, all calls to CreatePrefix on the returned
// Directory (or any subdirectories) will fail, and all directory prefixes will
// be automatically allocated. The default root directory does not allow manual
// prefixes.
func NewDirectoryLayer(nodeSS, contentSS subspace.Subspace, allowManualPrefixes bool) Directory {
var dl directoryLayer
dl.nodeSS = subspace.FromBytes(nodeSS.Bytes())
dl.contentSS = subspace.FromBytes(contentSS.Bytes())
dl.allowManualPrefixes = allowManualPrefixes
dl.rootNode = dl.nodeSS.Sub(dl.nodeSS.Bytes())
dl.allocator = newHCA(dl.rootNode.Sub([]byte("hca")))
return dl
}
