func writeLayerFromTar(r archive.Reader, w hcsshim.LayerWriter) (int64, error) {
t := tar.NewReader(r)
hdr, err := t.Next()
totalSize := int64(0)
buf := bufio.NewWriter(nil)
for err == nil {
base := path.Base(hdr.Name)
if strings.HasPrefix(base, archive.WhiteoutPrefix) {
name := path.Join(path.Dir(hdr.Name), base[len(archive.WhiteoutPrefix):])
err = w.Remove(filepath.FromSlash(name))
if err != nil {
return 0, err
}
hdr, err = t.Next()
} else if hdr.Typeflag == tar.TypeLink {
err = w.AddLink(filepath.FromSlash(hdr.Name), filepath.FromSlash(hdr.Linkname))
if err != nil {
return 0, err
}
hdr, err = t.Next()
} else {
var (
name string
size int64
fileInfo *winio.FileBasicInfo
)
name, size, fileInfo, err = backuptar.FileInfoFromHeader(hdr)
if err != nil {
return 0, err
}
err = w.Add(filepath.FromSlash(name), fileInfo)
if err != nil {
return 0, err
}
buf.Reset(w)
hdr, err = backuptar.WriteBackupStreamFromTarFile(buf, t, hdr)
ferr := buf.Flush()
if ferr != nil {
err = ferr
}
totalSize += size
}
}
if err != io.EOF {
return 0, err
}
return totalSize, nil
}
func writeLayerFromTar(r archive.Reader, w hcsshim.LayerWriter) (int64, error) {
t := tar.NewReader(r)
hdr, err := t.Next()
totalSize := int64(0)
buf := bufio.NewWriter(nil)
for err == nil {
base := path.Base(hdr.Name)
if strings.HasPrefix(base, archive.WhiteoutPrefix) {
name := path.Join(path.Dir(hdr.Name), base[len(archive.WhiteoutPrefix):])
err = w.Remove(filepath.FromSlash(name))
if err != nil {
return 0, err
}
hdr, err = t.Next()
} else if hdr.Typeflag == tar.TypeLink {
err = w.AddLink(filepath.FromSlash(hdr.Name), filepath.FromSlash(hdr.Linkname))
if err != nil {
return 0, err
}
hdr, err = t.Next()
} else {
var (
name string
size int64
fileInfo *winio.FileBasicInfo
)
name, size, fileInfo, err = backuptar.FileInfoFromHeader(hdr)
if err != nil {
return 0, err
}
err = w.Add(filepath.FromSlash(name), fileInfo)
if err != nil {
return 0, err
}
buf.Reset(w)
// Add the Hyper-V Virutal Machine group ACE to the security descriptor
// for TP5 so that Xenons can access all files. This is not necessary
// for post-TP5 builds.
if isTP5OrOlder() {
if sddl, ok := hdr.Winheaders["sd"]; ok {
var ace string
if hdr.Typeflag == tar.TypeDir {
ace = "(A;OICI;0x1200a9;;;S-1-5-83-0)"
} else {
ace = "(A;;0x1200a9;;;S-1-5-83-0)"
}
if hdr.Winheaders["sd"], ok = addAceToSddlDacl(sddl, ace); !ok {
logrus.Debugf("failed to add VM ACE to %s", sddl)
}
}
}
hdr, err = backuptar.WriteBackupStreamFromTarFile(buf, t, hdr)
ferr := buf.Flush()
if ferr != nil {
err = ferr
}
totalSize += size
}
}
if err != io.EOF {
return 0, err
}
return totalSize, nil
}