restic: extract Node filesystem code to fs package

internal/fs/node_unix.go

@@ -0,0 +1,31 @@
+//go:build !windows
+// +build !windows
+
+package fs
+
+import (
+	"os"
+	"syscall"
+)
+
+func lchown(name string, uid, gid int) error {
+	return os.Lchown(name, uid, gid)
+}
+
+type statT syscall.Stat_t
+
+func toStatT(i interface{}) (*statT, bool) {
+	s, ok := i.(*syscall.Stat_t)
+	if ok && s != nil {
+		return (*statT)(s), true
+	}
+	return nil, false
+}
+
+func (s statT) dev() uint64   { return uint64(s.Dev) }
+func (s statT) ino() uint64   { return uint64(s.Ino) }
+func (s statT) nlink() uint64 { return uint64(s.Nlink) }
+func (s statT) uid() uint32   { return uint32(s.Uid) }
+func (s statT) gid() uint32   { return uint32(s.Gid) }
+func (s statT) rdev() uint64  { return uint64(s.Rdev) }
+func (s statT) size() int64   { return int64(s.Size) }