// Parse a string representation of a CSeq header, returning a slice of at most one CSeq.
func parseCSeq(headerName string, headerText string) (
headers []base.SipHeader, err error) {
var cseq base.CSeq
parts := splitByWhitespace(headerText)
if len(parts) != 2 {
err = fmt.Errorf("CSeq field should have precisely one whitespace section: '%s'",
headerText)
return
}
var seqno uint64
seqno, err = strconv.ParseUint(parts[0], 10, 32)
if err != nil {
return
}
if seqno > MAX_CSEQ {
err = fmt.Errorf("invalid CSeq %d: exceeds maximum permitted value "+
"2**31 - 1", seqno)
return
}
cseq.SeqNo = uint32(seqno)
cseq.MethodName = base.Method(strings.TrimSpace(parts[1]))
if strings.Contains(string(cseq.MethodName), ";") {
err = fmt.Errorf("unexpected ';' in CSeq body: %s", headerText)
return
}
headers = []base.SipHeader{&cseq}
return
}
// Parse the first line of a SIP request, e.g: // INVITE [email protected] SIP/2.0 // REGISTER [email protected] SIP/1.0 func parseRequestLine(requestLine string) ( method base.Method, recipient base.Uri, sipVersion string, err error) { parts := strings.Split(requestLine, " ") if len(parts) != 3 { err = fmt.Errorf("request line should have 2 spaces: '%s'", requestLine) return } method = base.Method(strings.ToUpper(parts[0])) recipient, err = ParseUri(parts[1]) sipVersion = parts[2] switch recipient.(type) { case *base.WildcardUri: err = fmt.Errorf("wildcard URI '*' not permitted in request line: '%s'", requestLine) } return }