Merge pull request #17 from Microsoft/fix_symlink

Backuptar: replace slash with backslash on link target

backuptar/tar.go

@@ -284,7 +284,7 @@ func WriteBackupStreamFromTarFile(w io.Writer, t *tar.Reader, hdr *tar.Header) (
 	if hdr.Typeflag == tar.TypeSymlink {
 		_, isMountPoint := hdr.Winheaders[hdrMountPoint]
 		rp := winio.ReparsePoint{
-			Target:       hdr.Linkname,
+			Target:       filepath.FromSlash(hdr.Linkname),
 			IsMountPoint: isMountPoint,
 		}
 		reparse := winio.EncodeReparsePoint(&rp)

reparse.go

@@ -80,7 +80,7 @@ func EncodeReparsePoint(rp *ReparsePoint) []byte {
 	var ntTarget string
 	relative := false
 	if strings.HasPrefix(rp.Target, `\\?\`) {
-		ntTarget = rp.Target
+		ntTarget = `\??\` + rp.Target[4:]
 	} else if strings.HasPrefix(rp.Target, `\\`) {
 		ntTarget = `\??\UNC\` + rp.Target[2:]
 	} else if len(rp.Target) >= 2 && isDriveLetter(rp.Target[0]) && rp.Target[1] == ':' {