Method AddPacketToQueue

library/cpp/netliba/v12/udp_socket.cpp:409–447

    }

    void TUdpSocket::AddPacketToQueue(size_t size, const TSockAddrPair& addr, ui8 tos, size_t mtu) {
        Y_ASSERT(LastReturnedPacketBuffer);
        Y_ASSERT(size < LastReturnPacketBufferDataSize);

        char* packet = LastReturnedPacketBuffer;
        LastReturnedPacketBuffer = nullptr;

        const size_t packetSize = size + UDP_LOW_LEVEL_HEADER_SIZE;
        Y_ASSERT(packetSize <= UDP_MAX_PACKET_SIZE);

        WritePacketHeader(packet, packetSize, addr.RemoteAddr);

#ifdef SIMULATE_NETWORK_FAILURES
        // can't simulate packet loss - we must add packet to PacketsHeaders because we already allocated space in PacketsDataBuffer.
        if ((RandomNumber<size_t>() % 3) == 0)
            packet[RandomNumber<size_t>() % packetSize] += RandomNumber<size_t>(); // packet broken
#endif

        // Trying to append this packet to already existing in packet queue.
        const TIoVec iovValue = CreateIoVec(packet, packetSize);
        if (TryToApplySmallPacketsOptimization(iovValue, addr, tos, mtu)) {
            return;
        }

        // OK, creating new packet.
        LastUdpPacketSize = packetSize;

        TIoVec& iov = *PacketsIoVecs.PushBack(iovValue);

        Y_ASSERT(!UdpPacketsAddresses.Full());
        sockaddr_in6& name = *UdpPacketsAddresses.PushBack(addr.RemoteAddr);

        char* ctrlBuffer = UdpPacketsAuxData.GetContinuousRegion(CTRL_BUFFER_SIZE);

        UdpPacketsHeaders.resize(UdpPacketsHeaders.size() + 1);
        TMsgHdr& hdr = UdpPacketsHeaders.back().msg_hdr;

        hdr = CreateNl12SendMsgHdr(name, addr.MyAddr, iov, tos, ctrlBuffer, CTRL_BUFFER_SIZE);
    }

    void TUdpSocket::ForgetHeadUdpPackets(const size_t numPackets) {
        // necessary for TCircularPodBuffer::EraseBefore