migrate to go modules

Signed-off-by: Valentin Rothberg <rothberg@redhat.com>

vendor/github.com/Microsoft/hcsshim/internal/hcs/utils.go

@@ -0,0 +1,33 @@
+package hcs
+
+import (
+	"io"
+	"syscall"
+
+	"github.com/Microsoft/go-winio"
+)
+
+// makeOpenFiles calls winio.MakeOpenFile for each handle in a slice but closes all the handles
+// if there is an error.
+func makeOpenFiles(hs []syscall.Handle) (_ []io.ReadWriteCloser, err error) {
+	fs := make([]io.ReadWriteCloser, len(hs))
+	for i, h := range hs {
+		if h != syscall.Handle(0) {
+			if err == nil {
+				fs[i], err = winio.MakeOpenFile(h)
+			}
+			if err != nil {
+				syscall.Close(h)
+			}
+		}
+	}
+	if err != nil {
+		for _, f := range fs {
+			if f != nil {
+				f.Close()
+			}
+		}
+		return nil, err
+	}
+	return fs, nil
+}