You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: sniffer.go
    path of file: ./repos/tegola/vendor/github.com/SAP/go-hdb/driver
    
    the code of the file until where you have to start completion: package driver

// TODO Sniffer
/*
sniffer:
- complete for go-hdb: especially call with table parameters
- delete caches for statement and result
- don't ignore part read error
  - example: read scramsha256InitialReply got silently stuck because methodname check failed
- test with python client and handle surprises
  - an
    
func (r *sniffDownReader) readMsg() error {
	var stmtID uint64
	//resMeta := &resultMetadata{}
	//prmMeta := &parameterMetadata{}

	if err := r.pr.IterateParts(func(ph *p.PartHeader) {
		switch ph.PartKind {
		case p.PkStatementID:
			r.pr.Read((*p.StatementID)(&stmtID))
		case p.PkResultMetadata:
			r.pr.Read(r.resMeta)
		case p.PkParameterMetadata:
			r.pr.Read(r.prmMeta)
		case p.PkOutputParameters:
			outFields := []*p.ParameterField{}
			for _, f := range r.prmMeta.ParameterFields {
				if f.Out() {
					outFields = append(outFields, f)
				}
			}
			outPrms := &p.OutputParameters{OutputFields: outFields}
			r.pr.Read(outPrms)
		case p.PkResultset:
			resSet := &p.Resultset{ResultFields: r.resMeta.ResultFields}
			r.pr.Read(resSet)
		}
	}); err != nil {
		return err
	}
	_resMetaCache.put(stmtID, r.resMeta)
	_prmMetaCache.put(stmtID, r.prmMeta)
	return nil
}