fn add_headers()

in neqo-http3/src/recv_message.rs [153:196]
41 lines of code
10 McCabe index (conditional complexity)

    fn add_headers(&mut self, mut headers: Vec<Header>, fin: bool) -> Res<()> {
        qtrace!("[{self}] Add new headers fin={fin}");
        let interim = match self.message_type {
            MessageType::Request => false,
            MessageType::Response => is_interim(&headers)?,
        };
        headers_valid(&headers, self.message_type)?;
        if self.message_type == MessageType::Response {
            headers.retain(Header::is_allowed_for_response);
        }

        if fin && interim {
            return Err(Error::HttpGeneralProtocolStream);
        }

        let is_web_transport = self.message_type == MessageType::Request
            && headers.contains_header(":method", "CONNECT")
            && headers.contains_header(":protocol", "webtransport");
        if is_web_transport {
            self.conn_events
                .extended_connect_new_session(self.stream_id, headers);
        } else {
            self.conn_events
                .header_ready(self.get_stream_info(), headers, interim, fin);
        }

        if fin {
            self.set_closed();
        } else {
            self.state = if is_web_transport {
                self.stream_type = Http3StreamType::ExtendedConnect;
                RecvMessageState::ExtendedConnect
            } else if interim {
                RecvMessageState::WaitingForResponseHeaders {
                    frame_reader: FrameReader::new(),
                }
            } else {
                RecvMessageState::WaitingForData {
                    frame_reader: FrameReader::new(),
                }
            };
        }
        Ok(())
    }