ftr      coverage.CounterFileFooter
	shdr     coverage.CounterSegmentHeader
	u32b     []byte
	u8b      []byte
	fcnCount uint32
	segCount uint32
	debug    bool
}

func NewCounterDataReader(fn string, rs io.ReadSeeker) (*CounterDataReader, error) {
	cdr := &CounterDataReader{
		mr:   rs,
		u32b: make([]byte, 4),
		u8b:  make([]byte, 1),
	}
	// Read header