reader: set boolean flag when Rock Ridge is supported

Author: kdomanski

image_reader.go

@@ -175,9 +175,15 @@ func (f *File) GetAllChildren() ([]*File, error) {
 						return nil, fmt.Errorf("invalid SP record: %w", err)
 					}
 
+					hasRockRidge, err := suspHasRockRidge(newDE.SystemUseEntries)
+					if err != nil {
+						return nil, fmt.Errorf("failed to check for Rock Ridge extension: %w", err)
+					}
+
 					// save SUSP offset from the SP record
 					f.susp = &SUSPMetadata{
-						Offset: sprecord.BytesSkipped,
+						Offset:       sprecord.BytesSkipped,
+						HasRockRidge: hasRockRidge,
 					}
 				}
 			} else {

image_reader_test.go

@@ -155,6 +155,7 @@ func TestImageReaderSUSP(t *testing.T) {
 	assert.Equal(t, "LOREM_IP.TXT", loremFile.Name())
 	assert.Equal(t, int64(446), loremFile.Size())
 	assert.NotNil(t, loremFile.susp)
+	assert.True(t, loremFile.susp.HasRockRidge)
 
 	data, err := io.ReadAll(loremFile.Reader())
 	assert.NoError(t, err)

susp.go

@@ -195,7 +195,8 @@ func splitSystemUseEntries(data []byte, ra io.ReaderAt) ([]SystemUseEntry, error
 }
 
 type SUSPMetadata struct {
-	Offset uint8
+	Offset       uint8
+	HasRockRidge bool
 }
 
 func (sm *SUSPMetadata) Clone() *SUSPMetadata {
@@ -204,6 +205,7 @@ func (sm *SUSPMetadata) Clone() *SUSPMetadata {
 	}
 
 	return &SUSPMetadata{
-		Offset: sm.Offset,
+		Offset:       sm.Offset,
+		HasRockRidge: sm.HasRockRidge,
 	}
 }