// +build !windows
 
 package image
 
 import "github.com/docker/docker/layer"
 
 // RootFS describes images root filesystem
 // This is currently a placeholder that only supports layers. In the future

 // this can be made into a interface that supports different implementations.

 type RootFS struct {
 	Type    string         `json:"type"`
 	DiffIDs []layer.DiffID `json:"diff_ids,omitempty"`
 }
 
 // ChainID returns the ChainID for the top layer in RootFS.
 func (r *RootFS) ChainID() layer.ChainID {
 	return layer.CreateChainID(r.DiffIDs)
 }
 
 // NewRootFS returns empty RootFS struct
 func NewRootFS() *RootFS {
 	return &RootFS{Type: "layers"}
 }