Method SendTo

library/cpp/netliba/v6/udp_socket.cpp:138–166

    }

    TNetSocket::ESendError TNetSocket::SendTo(const char* buf, int size, const sockaddr_in6& toAddress, const EFragFlag frag) const {
        Y_ASSERT(size >= UDP_LOW_LEVEL_HEADER_SIZE);
        ui32 crc = CalcChecksum(buf + UDP_LOW_LEVEL_HEADER_SIZE, size - UDP_LOW_LEVEL_HEADER_SIZE);
        ui32 ipCrc = CalcAddressCrc(toAddress);
        ui32 portCrc = toAddress.sin6_port;
        *(ui32*)buf = crc + ipCrc + portCrc;
#ifdef SIMULATE_NETWORK_FAILURES
        if ((RandomNumber<size_t>() % 3) == 0)
            return true; // packet lost
        if ((RandomNumber<size_t>() % 3) == 0)
            (char&)(buf[RandomNumber<size_t>() % size]) += RandomNumber<size_t>(); // packet broken
#endif

        char tosBuffer[NNetlibaSocket::TOS_BUFFER_SIZE];
        void* t = NNetlibaSocket::CreateTos(Tos, tosBuffer);
        const NNetlibaSocket::TIoVec iov = NNetlibaSocket::CreateIoVec((char*)buf, size);
        NNetlibaSocket::TMsgHdr hdr = NNetlibaSocket::CreateSendMsgHdr(toAddress, iov, t);

        const int rv = s->SendMsg(&hdr, 0, frag);
        if (rv < 0) {
            if (errno == EHOSTUNREACH || errno == ENETUNREACH) {
                return SEND_NO_ROUTE_TO_HOST;
            } else {
                return SEND_BUFFER_OVERFLOW;
            }
        }
        Y_ASSERT(rv == size);
        return SEND_OK;
    }

    inline bool CrcMatches(ui32 pktCrc, ui32 crc, const sockaddr_in6& addr) {
        Y_ASSERT(LocalHostFound);