// importLayer adds a new layer to the tag and graph store based on the given data.
func (d *Driver) importLayer(id string, layerData archive.Reader, parentLayerPaths []string) (size int64, err error) {
var w hcsshim.LayerWriter
w, err = hcsshim.NewLayerWriter(d.info, id, parentLayerPaths)
if err != nil {
return
}
size, err = writeLayerFromTar(layerData, w)
if err != nil {
w.Close()
return
}
err = w.Close()
if err != nil {
return
}
return
}
// writeLayer is the re-exec entry point for writing a layer from a tar file
func writeLayer() {
home := os.Args[1]
id := os.Args[2]
parentLayerPaths := os.Args[3:]
err := func() error {
err := winio.EnableProcessPrivileges([]string{winio.SeBackupPrivilege, winio.SeRestorePrivilege})
if err != nil {
return err
}
info := hcsshim.DriverInfo{
Flavour: filterDriver,
HomeDir: home,
}
w, err := hcsshim.NewLayerWriter(info, id, parentLayerPaths)
if err != nil {
return err
}
size, err := writeLayerFromTar(os.Stdin, w)
if err != nil {
return err
}
err = w.Close()
if err != nil {
return err
}
fmt.Fprint(os.Stdout, size)
return nil
}()
if err != nil {
fmt.Fprint(os.Stderr, err)
os.Exit(1)
}
}
// writeLayer writes a layer from a tar file.
func writeLayer(layerData io.Reader, home string, id string, parentLayerPaths ...string) (int64, error) {
err := winio.EnableProcessPrivileges([]string{winio.SeBackupPrivilege, winio.SeRestorePrivilege})
if err != nil {
return 0, err
}
if noreexec {
defer func() {
if err := winio.DisableProcessPrivileges([]string{winio.SeBackupPrivilege, winio.SeRestorePrivilege}); err != nil {
// This should never happen, but just in case when in debugging mode.
// See https://github.com/docker/docker/pull/28002#discussion_r86259241 for rationale.
panic("Failed to disabled process privileges while in non re-exec mode")
}
}()
}
info := hcsshim.DriverInfo{
Flavour: filterDriver,
HomeDir: home,
}
w, err := hcsshim.NewLayerWriter(info, id, parentLayerPaths)
if err != nil {
return 0, err
}
size, err := writeLayerFromTar(layerData, w, filepath.Join(home, id))
if err != nil {
return 0, err
}
err = w.Close()
if err != nil {
return 0, err
}
return size, nil
}
// importLayer adds a new layer to the tag and graph store based on the given data.
func (d *Driver) importLayer(id string, layerData archive.Reader, parentLayerPaths []string) (size int64, err error) {
if hcsshim.IsTP4() {
// Import from TP4 format to maintain compatibility with existing images.
var tempFolder string
tempFolder, err = ioutil.TempDir("", "hcs")
if err != nil {
return
}
defer os.RemoveAll(tempFolder)
if size, err = chrootarchive.ApplyLayer(tempFolder, layerData); err != nil {
return
}
if err = hcsshim.ImportLayer(d.info, id, tempFolder, parentLayerPaths); err != nil {
return
}
return
}
var w hcsshim.LayerWriter
w, err = hcsshim.NewLayerWriter(d.info, id, parentLayerPaths)
if err != nil {
return
}
size, err = writeLayerFromTar(layerData, w)
if err != nil {
w.Close()
return
}
err = w.Close()
if err != nil {
return
}
return
}