Method synchronizeWithGroup

srtcore/core.cpp:3596–3683

}

void srt::CUDT::synchronizeWithGroup(CUDTGroup* gp)
{
    ScopedLock gl (*gp->exp_groupLock());

    // We have blocked here the process of connecting a new
    // socket and adding anything new to the group, so no such
    // thing may happen in the meantime.
    steady_clock::time_point start_time, peer_start_time;

    start_time = m_stats.tsStartTime;
    peer_start_time = m_tsRcvPeerStartTime;

    if (!gp->applyGroupTime((start_time), (peer_start_time)))
    {
        HLOGC(gmlog.Debug,
              log << CONID() << "synchronizeWithGroup: ST=" << FormatTime(m_stats.tsStartTime) << " -> "
                  << FormatTime(start_time) << " PST=" << FormatTime(m_tsRcvPeerStartTime) << " -> "
                  << FormatTime(peer_start_time));
        m_stats.tsStartTime  = start_time;
        m_tsRcvPeerStartTime = peer_start_time;
    }
    else
    {
        // This was the first connected socket and it defined start time.
        HLOGC(gmlog.Debug,
              log << CONID() << "synchronizeWithGroup: ST=" << FormatTime(m_stats.tsStartTime)
                  << " PST=" << FormatTime(m_tsRcvPeerStartTime));
    }

    steady_clock::time_point rcv_buffer_time_base;
    bool rcv_buffer_wrap_period = false;
    steady_clock::duration rcv_buffer_udrift(0);
    if (m_bTsbPd && gp->getBufferTimeBase(this, (rcv_buffer_time_base), (rcv_buffer_wrap_period), (rcv_buffer_udrift)))
    {
        // We have at least one socket in the group, each socket should have
        // the value of the timebase set exactly THE SAME.

        // In case when we have the following situation:

        // - the existing link is before [LAST30] (so wrap period is off)
        // - the new link gets the timestamp from [LAST30] range
        // --> this will be recognized as entering the wrap period, next
        //     timebase will get added a segment to this value
        //
        // The only dangerous situations could be when one link gets
        // timestamps from the [FOLLOWING30] and the other in [FIRST30],
        // but between them there's a 30s distance, considered large enough
        // time to not fill a network window.
        enterCS(m_RecvLock);
        m_pRcvBuffer->applyGroupTime(rcv_buffer_time_base, rcv_buffer_wrap_period, m_iTsbPdDelay_ms * 1000, rcv_buffer_udrift);
        m_pRcvBuffer->setPeerRexmitFlag(m_bPeerRexmitFlag);
        leaveCS(m_RecvLock);

        HLOGC(gmlog.Debug, log << "AFTER HS: Set Rcv TsbPd mode: delay="
                << (m_iTsbPdDelay_ms/1000) << "." << (m_iTsbPdDelay_ms%1000)
                << "s GROUP TIME BASE: " << FormatTime(rcv_buffer_time_base)
                << " (" << (rcv_buffer_wrap_period ? "" : "NOT") << " WRAP PERIOD)");
    }