make docker compile on freebsd

Signed-off-by: Alexey Guskov <lexag@mail.ru>

system/stat_freebsd.go

@@ -0,0 +1,27 @@
+package system
+
+import (
+	"syscall"
+)
+
+// fromStatT converts a syscall.Stat_t type to a system.Stat_t type
+func fromStatT(s *syscall.Stat_t) (*Stat_t, error) {
+	return &Stat_t{size: s.Size,
+		mode: uint32(s.Mode),
+		uid:  s.Uid,
+		gid:  s.Gid,
+		rdev: uint64(s.Rdev),
+		mtim: s.Mtimespec}, nil
+}
+
+// Stat takes a path to a file and returns
+// a system.Stat_t type pertaining to that file.
+//
+// Throws an error if the file does not exist
+func Stat(path string) (*Stat_t, error) {
+	s := &syscall.Stat_t{}
+	if err := syscall.Stat(path, s); err != nil {
+		return nil, err
+	}
+	return fromStatT(s)
+}