Method Connect

library/cpp/neh/https.cpp:458–518

            }

            TConnectionRef Connect(TCont* c, const TString& msgAddr, const TResolvedHost& addr, TErrorRef* error) {
                if (ExceedHardLimit()) {
                    if (error) {
                        *error = new TError("neh::https output connections limit reached", TError::TType::UnknownType);
                    }
                    return nullptr;
                }

                TConnectionRef res;
                TConnList& connList = ConnList(addr);

                while (connList.Dequeue(&res)) {
                    ActiveConnections.Inc();
                    CachedConnections.Dec();
                    if (IsNotSocketClosedByOtherSide((*res)->Fd()) && !(*res)->ShutdownReceived()) {
                        return res;
                    }
                }

                if (!c) {
                    if (error) {
                        *error = new TError("directo connection failed");
                    }
                    return nullptr;
                }

                const TInstant now(TInstant::Now());
                const TInstant deadline(now + TDuration::Seconds(10));
                TDuration delay = TDuration::MilliSeconds(8);
                TInstant checkpoint = Min(deadline, delay.ToDeadLine());

                TNetworkAddress::TIterator ait = addr.Addr.Begin();
                TSocketRef socket(new TSocketHolder(NCoro::Socket(*ait)));
                int ret = NCoro::ConnectD(c, *socket, *ait, deadline);
                res.Reset(new TConnectionHolder);
                res->Reset(new TConnection(socket, addr));

                if (ret) {
                    do {
                        if ((ret == ETIMEDOUT || ret == EINTR) && checkpoint < deadline) {
                            delay += delay;
                            checkpoint = Min(deadline, now + delay);
                            TConnectionRef res2;
                            if (connList.Dequeue(&res2)) {
                                ActiveConnections.Inc();
                                CachedConnections.Dec();
                                if (IsNotSocketClosedByOtherSide((*res2)->Fd()) && !(*res)->ShutdownReceived()) {
                                    return res2;
                                }
                            }
                        } else {
                            if (error) {
                                *error = new TError(TStringBuilder() << TStringBuf("can not connect to ") << msgAddr);
                            }
                            return nullptr;
                        }
                    } while (ret = NCoro::PollD(c, (*res)->Fd(), CONT_POLL_WRITE, checkpoint));
                }