Method setAttributes

snapshot/restore/local_fs_output.go:273–315

setAttributes sets permission, modification time and user/group ids on targetPath. modclear will clear the specified FileMod bits. Pass 0 to not clear any.

(targetPath string, e fs.Entry, modclear os.FileMode)

// on targetPath. modclear will clear the specified FileMod bits. Pass 0
// to not clear any.
func (o *FilesystemOutput) setAttributes(targetPath string, e fs.Entry, modclear os.FileMode) error {
	le, err := localfs.NewEntry(targetPath)
	if err != nil {
		return errors.Wrap(err, "could not create local FS entry for "+targetPath)
	}

	var (
		osChmod   = os.Chmod
		osChown   = os.Chown
		osChtimes = os.Chtimes
	)

	// symbolic links require special handling that is OS-specific and sometimes unsupported
	// os.* functions change the target of the symlink and not the symlink itself.
	if isSymlink(e) {
		osChmod, osChown, osChtimes = symlinkChmod, symlinkChown, symlinkChtimes
		modclear = os.FileMode(0)
	}

	// Set owner user and group from e
	// On Windows Chown is not supported. fs.OwnerInfo collected on Windows will always
	// be zero-value for UID and GID, so the Chown operation is not performed.
	if o.shouldUpdateOwner(le, e) {
		if err = o.maybeIgnorePermissionError(osChown(targetPath, int(e.Owner().UserID), int(e.Owner().GroupID))); err != nil {
			return errors.Wrap(err, "could not change owner/group for "+targetPath)
		}
	}

	// Set file permissions from e
	if o.shouldUpdatePermissions(le, e, modclear) {
		if err = o.maybeIgnorePermissionError(osChmod(targetPath, (e.Mode()&fs.ModBits)&^modclear)); err != nil {
			return errors.Wrap(err, "could not change permissions on "+targetPath)
		}
	}

	if o.shouldUpdateTimes(le, e) {
		if err = o.maybeIgnorePermissionError(osChtimes(targetPath, e.ModTime(), e.ModTime())); err != nil {
			return errors.Wrap(err, "could not change mod time on "+targetPath)
		}
	}

	return nil
}

func isSymlink(e fs.Entry) bool {
	_, ok := e.(fs.Symlink)