Add ReadOnly() function

Signed-off-by: Gabriel Adrian Samfira <gsamfira@cloudbasesolutions.com>

diff/windows/windows.go

@@ -335,15 +335,7 @@ func mountsToLayerAndParents(mounts []mount.Mount) (string, []string, error) {
 		return "", nil, err
 	}
 
-	isView := false
-	for _, o := range mnt.Options {
-		if o == "ro" {
-			isView = true
-			break
-		}
-	}
-
-	if isView {
+	if mnt.ReadOnly() {
 		if mnt.Type == "bind" && len(parentLayerPaths) != 0 {
 			return "", nil, fmt.Errorf("unexpected bind-mount View with parents: %w", errdefs.ErrInvalidArgument)
 		} else if mnt.Type == "bind" {

mount/mount_windows.go

@@ -38,18 +38,19 @@ var (
 	ErrNotImplementOnWindows = errors.New("not implemented under windows")
 )
 
-// Mount to the provided target.
-func (m *Mount) mount(target string) (retErr error) {
-	readOnly := false
+func (m *Mount) ReadOnly() bool {
 	for _, option := range m.Options {
 		if option == "ro" {
-			readOnly = true
-			break
+			return true
 		}
 	}
+	return false
+}
 
+// Mount to the provided target.
+func (m *Mount) mount(target string) (retErr error) {
 	if m.Type == "bind" {
-		if err := bindfilter.ApplyFileBinding(target, m.Source, readOnly); err != nil {
+		if err := bindfilter.ApplyFileBinding(target, m.Source, m.ReadOnly()); err != nil {
 			return fmt.Errorf("failed to bind-mount to %s: %w", target, err)
 		}
 		return nil
@@ -98,7 +99,7 @@ func (m *Mount) mount(target string) (retErr error) {
 		return fmt.Errorf("failed to get volume path for layer %s: %w", m.Source, err)
 	}
 
-	if err := bindfilter.ApplyFileBinding(target, volume, readOnly); err != nil {
+	if err := bindfilter.ApplyFileBinding(target, volume, m.ReadOnly()); err != nil {
 		return fmt.Errorf("failed to set volume mount path for layer %s: %w", m.Source, err)
 	}
 	defer func() {