if err != nil {
		return ErrInvalidChecksum
	}
	if cs == nil {
		return nil
	}
	r.contentHash = *cs
	return r.AddNonTrailingChecksum(cs, ignoreValue)
}

// AddNonTrailingChecksum will add a checksum to the reader.
// The checksum cannot be trailing.
func (r *Reader) AddNonTrailingChecksum(cs *Checksum, ignoreValue bool) error {
	if cs == nil {
		return nil
	}
	r.contentHash = *cs
	if ignoreValue {