restic: extract Node filesystem code to fs package

internal/fs/node_linux.go

@@ -0,0 +1,36 @@
+package fs
+
+import (
+	"path/filepath"
+	"syscall"
+
+	"golang.org/x/sys/unix"
+
+	"github.com/restic/restic/internal/errors"
+)
+
+func nodeRestoreSymlinkTimestamps(path string, utimes [2]syscall.Timespec) error {
+	dir, err := Open(filepath.Dir(path))
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	times := []unix.Timespec{
+		{Sec: utimes[0].Sec, Nsec: utimes[0].Nsec},
+		{Sec: utimes[1].Sec, Nsec: utimes[1].Nsec},
+	}
+
+	err = unix.UtimesNanoAt(int(dir.Fd()), filepath.Base(path), times, unix.AT_SYMLINK_NOFOLLOW)
+
+	if err != nil {
+		// ignore subsequent errors
+		_ = dir.Close()
+		return errors.Wrap(err, "UtimesNanoAt")
+	}
+
+	return dir.Close()
+}
+
+func (s statT) atim() syscall.Timespec { return s.Atim }
+func (s statT) mtim() syscall.Timespec { return s.Mtim }
+func (s statT) ctim() syscall.Timespec { return s.Ctim }