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srs/trunk/3rdparty/srt-1-fit/srtcore/group.cpp
Haibo Chen c5e067fb0b
Upgrade libsrt to v1.5.3. v5.0.183 v6.0.81 (#3808)
fix https://github.com/ossrs/srs/issues/3155
Build srt-1-fit fails with `standard attributes in middle of
decl-specifiers` on GCC 12,Arch Linux.

See https://github.com/Haivision/srt/releases/tag/v1.5.3
2023-09-21 22:23:56 +08:00

4145 lines
150 KiB
C++

#include "platform_sys.h"
#include <iterator>
#include "api.h"
#include "group.h"
using namespace std;
using namespace srt::sync;
using namespace srt::groups;
using namespace srt_logging;
// The SRT_DEF_VERSION is defined in core.cpp.
extern const int32_t SRT_DEF_VERSION;
namespace srt {
int32_t CUDTGroup::s_tokenGen = 0;
// [[using locked(this->m_GroupLock)]];
bool CUDTGroup::getBufferTimeBase(CUDT* forthesakeof,
steady_clock::time_point& w_tb,
bool& w_wp,
steady_clock::duration& w_dr)
{
CUDT* master = 0;
for (gli_t gi = m_Group.begin(); gi != m_Group.end(); ++gi)
{
CUDT* u = &gi->ps->core();
if (gi->laststatus != SRTS_CONNECTED)
{
HLOGC(gmlog.Debug,
log << "getBufferTimeBase: skipping @" << u->m_SocketID
<< ": not connected, state=" << SockStatusStr(gi->laststatus));
continue;
}
if (u == forthesakeof)
continue; // skip the member if it's the target itself
if (!u->m_pRcvBuffer)
continue; // Not initialized yet
master = u;
break; // found
}
// We don't have any sockets in the group, so can't get
// the buffer timebase. This should be then initialized
// the usual way.
if (!master)
return false;
master->m_pRcvBuffer->getInternalTimeBase((w_tb), (w_wp), (w_dr));
// Sanity check
if (is_zero(w_tb))
{
LOGC(gmlog.Error, log << "IPE: existing previously socket has no time base set yet!");
return false; // this will enforce initializing the time base normal way
}
return true;
}
// [[using locked(this->m_GroupLock)]];
bool CUDTGroup::applyGroupSequences(SRTSOCKET target, int32_t& w_snd_isn, int32_t& w_rcv_isn)
{
if (m_bConnected) // You are the first one, no need to change.
{
IF_HEAVY_LOGGING(string update_reason = "what?");
// Find a socket that is declared connected and is not
// the socket that caused the call.
for (gli_t gi = m_Group.begin(); gi != m_Group.end(); ++gi)
{
if (gi->id == target)
continue;
CUDT& se = gi->ps->core();
if (!se.m_bConnected)
continue;
// Found it. Get the following sequences:
// For sending, the sequence that is about to be sent next.
// For receiving, the sequence of the latest received packet.
// SndCurrSeqNo is initially set to ISN-1, this next one is
// the sequence that is about to be stamped on the next sent packet
// over that socket. Using this field is safer because it is atomic
// and its affinity is to the same thread as the sending function.
// NOTE: the groupwise scheduling sequence might have been set
// already. If so, it means that it was set by either:
// - the call of this function on the very first conencted socket (see below)
// - the call to `sendBroadcast` or `sendBackup`
// In both cases, we want THIS EXACTLY value to be reported
if (m_iLastSchedSeqNo != -1)
{
w_snd_isn = m_iLastSchedSeqNo;
IF_HEAVY_LOGGING(update_reason = "GROUPWISE snd-seq");
}
else
{
w_snd_isn = se.m_iSndNextSeqNo;
// Write it back to the groupwise scheduling sequence so that
// any next connected socket will take this value as well.
m_iLastSchedSeqNo = w_snd_isn;
IF_HEAVY_LOGGING(update_reason = "existing socket not yet sending");
}
// RcvCurrSeqNo is increased by one because it happens that at the
// synchronization moment it's already past reading and delivery.
// This is redundancy, so the redundant socket is connected at the moment
// when the other one is already transmitting, so skipping one packet
// even if later transmitted is less troublesome than requesting a
// "mistakenly seen as lost" packet.
w_rcv_isn = CSeqNo::incseq(se.m_iRcvCurrSeqNo);
HLOGC(gmlog.Debug,
log << "applyGroupSequences: @" << target << " gets seq from @" << gi->id << " rcv %" << (w_rcv_isn)
<< " snd %" << (w_snd_isn) << " as " << update_reason);
return false;
}
}
// If the GROUP (!) is not connected, or no running/pending socket has been found.
// // That is, given socket is the first one.
// The group data should be set up with its own data. They should already be passed here
// in the variables.
//
// Override the schedule sequence of the group in this case because whatever is set now,
// it's not valid.
HLOGC(gmlog.Debug,
log << "applyGroupSequences: no socket found connected and transmitting, @" << target
<< " not changing sequences, storing snd-seq %" << (w_snd_isn));
set_currentSchedSequence(w_snd_isn);
return true;
}
// NOTE: This function is now for DEBUG PURPOSES ONLY.
// Except for presenting the extracted data in the logs, there's no use of it now.
void CUDTGroup::debugMasterData(SRTSOCKET slave)
{
// Find at least one connection, which is running. Note that this function is called
// from within a handshake process, so the socket that undergoes this process is at best
// currently in SRT_GST_PENDING state and it's going to be in SRT_GST_IDLE state at the
// time when the connection process is done, until the first reading/writing happens.
ScopedLock cg(m_GroupLock);
IF_LOGGING(SRTSOCKET mpeer = SRT_INVALID_SOCK);
IF_LOGGING(steady_clock::time_point start_time);
bool found = false;
for (gli_t gi = m_Group.begin(); gi != m_Group.end(); ++gi)
{
if (gi->sndstate == SRT_GST_RUNNING)
{
// Found it. Get the socket's peer's ID and this socket's
// Start Time. Once it's delivered, this can be used to calculate
// the Master-to-Slave start time difference.
IF_LOGGING(mpeer = gi->ps->m_PeerID);
IF_LOGGING(start_time = gi->ps->core().socketStartTime());
HLOGC(gmlog.Debug,
log << "getMasterData: found RUNNING master @" << gi->id << " - reporting master's peer $" << mpeer
<< " starting at " << FormatTime(start_time));
found = true;
break;
}
}
if (!found)
{
// If no running one found, then take the first socket in any other
// state than broken, except the slave. This is for a case when a user
// has prepared one link already, but hasn't sent anything through it yet.
for (gli_t gi = m_Group.begin(); gi != m_Group.end(); ++gi)
{
if (gi->sndstate == SRT_GST_BROKEN)
continue;
if (gi->id == slave)
continue;
// Found it. Get the socket's peer's ID and this socket's
// Start Time. Once it's delivered, this can be used to calculate
// the Master-to-Slave start time difference.
IF_LOGGING(mpeer = gi->ps->core().m_PeerID);
IF_LOGGING(start_time = gi->ps->core().socketStartTime());
HLOGC(gmlog.Debug,
log << "getMasterData: found IDLE/PENDING master @" << gi->id << " - reporting master's peer $" << mpeer
<< " starting at " << FormatTime(start_time));
found = true;
break;
}
}
if (!found)
{
LOGC(cnlog.Debug, log << CONID() << "NO GROUP MASTER LINK found for group: $" << id());
}
else
{
// The returned master_st is the master's start time. Calculate the
// differene time.
IF_LOGGING(steady_clock::duration master_tdiff = m_tsStartTime - start_time);
LOGC(cnlog.Debug, log << CONID() << "FOUND GROUP MASTER LINK: peer=$" << mpeer
<< " - start time diff: " << FormatDuration<DUNIT_S>(master_tdiff));
}
}
// GROUP
CUDTGroup::SocketData* CUDTGroup::add(SocketData data)
{
ScopedLock g(m_GroupLock);
// Change the snd/rcv state of the group member to PENDING.
// Default for SocketData after creation is BROKEN, which just
// after releasing the m_GroupLock could be read and interpreted
// as broken connection and removed before the handshake process
// is done.
data.sndstate = SRT_GST_PENDING;
data.rcvstate = SRT_GST_PENDING;
LOGC(gmlog.Note, log << "group/add: adding member @" << data.id << " into group $" << id());
m_Group.push_back(data);
gli_t end = m_Group.end();
if (m_iMaxPayloadSize == -1)
{
int plsize = (int)data.ps->core().OPT_PayloadSize();
HLOGC(gmlog.Debug,
log << "CUDTGroup::add: taking MAX payload size from socket @" << data.ps->m_SocketID << ": " << plsize
<< " " << (plsize ? "(explicit)" : "(unspecified = fallback to 1456)"));
if (plsize == 0)
plsize = SRT_LIVE_MAX_PLSIZE;
// It is stated that the payload size
// is taken from first, and every next one
// will get the same.
m_iMaxPayloadSize = plsize;
}
--end;
return &*end;
}
CUDTGroup::CUDTGroup(SRT_GROUP_TYPE gtype)
: m_Global(CUDT::uglobal())
, m_GroupID(-1)
, m_PeerGroupID(-1)
, m_type(gtype)
, m_listener()
, m_iBusy()
, m_iSndOldestMsgNo(SRT_MSGNO_NONE)
, m_iSndAckedMsgNo(SRT_MSGNO_NONE)
, m_uOPT_MinStabilityTimeout_us(1000 * CSrtConfig::COMM_DEF_MIN_STABILITY_TIMEOUT_MS)
// -1 = "undefined"; will become defined with first added socket
, m_iMaxPayloadSize(-1)
, m_bSynRecving(true)
, m_bSynSending(true)
, m_bTsbPd(true)
, m_bTLPktDrop(true)
, m_iTsbPdDelay_us(0)
// m_*EID and m_*Epolld fields will be initialized
// in the constructor body.
, m_iSndTimeOut(-1)
, m_iRcvTimeOut(-1)
, m_tsStartTime()
, m_tsRcvPeerStartTime()
, m_RcvBaseSeqNo(SRT_SEQNO_NONE)
, m_bOpened(false)
, m_bConnected(false)
, m_bClosing(false)
, m_iLastSchedSeqNo(SRT_SEQNO_NONE)
, m_iLastSchedMsgNo(SRT_MSGNO_NONE)
{
setupMutex(m_GroupLock, "Group");
setupMutex(m_RcvDataLock, "RcvData");
setupCond(m_RcvDataCond, "RcvData");
m_RcvEID = m_Global.m_EPoll.create(&m_RcvEpolld);
m_SndEID = m_Global.m_EPoll.create(&m_SndEpolld);
m_stats.init();
// Set this data immediately during creation before
// two or more sockets start arguing about it.
m_iLastSchedSeqNo = CUDT::generateISN();
}
CUDTGroup::~CUDTGroup()
{
srt_epoll_release(m_RcvEID);
srt_epoll_release(m_SndEID);
releaseMutex(m_GroupLock);
releaseMutex(m_RcvDataLock);
releaseCond(m_RcvDataCond);
}
void CUDTGroup::GroupContainer::erase(CUDTGroup::gli_t it)
{
if (it == m_LastActiveLink)
{
if (m_List.empty())
{
LOGC(gmlog.Error, log << "IPE: GroupContainer is empty and 'erase' is called on it.");
m_LastActiveLink = m_List.end();
return; // this avoids any misunderstandings in iterator checks
}
gli_t bb = m_List.begin();
++bb;
if (bb == m_List.end()) // means: m_List.size() == 1
{
// One element, this one being deleted, nothing to point to.
m_LastActiveLink = m_List.end();
}
else
{
// Set the link to the previous element IN THE RING.
// We have the position pointer.
// Reverse iterator is automatically decremented.
std::reverse_iterator<gli_t> rt(m_LastActiveLink);
if (rt == m_List.rend())
rt = m_List.rbegin();
m_LastActiveLink = rt.base();
// This operation is safe because we know that:
// - the size of the container is at least 2 (0 and 1 cases are handled above)
// - if m_LastActiveLink == m_List.begin(), `rt` is shifted to the opposite end.
--m_LastActiveLink;
}
}
m_List.erase(it);
--m_SizeCache;
}
void CUDTGroup::setOpt(SRT_SOCKOPT optName, const void* optval, int optlen)
{
HLOGC(gmlog.Debug,
log << "GROUP $" << id() << " OPTION: #" << optName
<< " value:" << FormatBinaryString((uint8_t*)optval, optlen));
switch (optName)
{
case SRTO_RCVSYN:
m_bSynRecving = cast_optval<bool>(optval, optlen);
return;
case SRTO_SNDSYN:
m_bSynSending = cast_optval<bool>(optval, optlen);
return;
case SRTO_SNDTIMEO:
m_iSndTimeOut = cast_optval<int>(optval, optlen);
break;
case SRTO_RCVTIMEO:
m_iRcvTimeOut = cast_optval<int>(optval, optlen);
break;
case SRTO_GROUPMINSTABLETIMEO:
{
const int val_ms = cast_optval<int>(optval, optlen);
const int min_timeo_ms = (int) CSrtConfig::COMM_DEF_MIN_STABILITY_TIMEOUT_MS;
if (val_ms < min_timeo_ms)
{
LOGC(qmlog.Error,
log << "group option: SRTO_GROUPMINSTABLETIMEO min allowed value is " << min_timeo_ms << " ms.");
throw CUDTException(MJ_NOTSUP, MN_INVAL, 0);
}
// Search if you already have SRTO_PEERIDLETIMEO set
int idletmo = CSrtConfig::COMM_RESPONSE_TIMEOUT_MS;
vector<ConfigItem>::iterator f =
find_if(m_config.begin(), m_config.end(), ConfigItem::OfType(SRTO_PEERIDLETIMEO));
if (f != m_config.end())
{
f->get(idletmo); // worst case, it will leave it unchanged.
}
if (val_ms > idletmo)
{
LOGC(qmlog.Error,
log << "group option: SRTO_GROUPMINSTABLETIMEO=" << val_ms << " exceeds SRTO_PEERIDLETIMEO=" << idletmo);
throw CUDTException(MJ_NOTSUP, MN_INVAL, 0);
}
m_uOPT_MinStabilityTimeout_us = 1000 * val_ms;
}
break;
default:
break;
}
// All others must be simply stored for setting on a socket.
// If the group is already open and any post-option is about
// to be modified, it must be allowed and applied on all sockets.
if (m_bOpened)
{
// There's at least one socket in the group, so only
// post-options are allowed.
if (!binary_search(srt_post_opt_list, srt_post_opt_list + SRT_SOCKOPT_NPOST, optName))
{
LOGC(gmlog.Error, log << "setsockopt(group): Group is connected, this option can't be altered");
throw CUDTException(MJ_NOTSUP, MN_ISCONNECTED, 0);
}
HLOGC(gmlog.Debug, log << "... SPREADING to existing sockets.");
// This means that there are sockets already, so apply
// this option on them.
std::vector<CUDTSocket*> ps_vec;
{
// Do copy to avoid deadlock. CUDT::setOpt() cannot be called directly inside this loop, because
// CUDT::setOpt() will lock m_ConnectionLock, which should be locked before m_GroupLock.
ScopedLock gg(m_GroupLock);
for (gli_t gi = m_Group.begin(); gi != m_Group.end(); ++gi)
{
ps_vec.push_back(gi->ps);
}
}
for (std::vector<CUDTSocket*>::iterator it = ps_vec.begin(); it != ps_vec.end(); ++it)
{
(*it)->core().setOpt(optName, optval, optlen);
}
}
// Store the option regardless if pre or post. This will apply
m_config.push_back(ConfigItem(optName, optval, optlen));
}
static bool getOptDefault(SRT_SOCKOPT optname, void* optval, int& w_optlen);
// unfortunately this is required to properly handle th 'default_opt != opt'
// operation in the below importOption. Not required simultaneously operator==.
static bool operator!=(const struct linger& l1, const struct linger& l2)
{
return l1.l_onoff != l2.l_onoff || l1.l_linger != l2.l_linger;
}
template <class ValueType>
static void importOption(vector<CUDTGroup::ConfigItem>& storage, SRT_SOCKOPT optname, const ValueType& field)
{
ValueType default_opt = ValueType();
int default_opt_size = sizeof(ValueType);
ValueType opt = field;
if (!getOptDefault(optname, (&default_opt), (default_opt_size)) || default_opt != opt)
{
// Store the option when:
// - no default for this option is found
// - the option value retrieved from the field is different than default
storage.push_back(CUDTGroup::ConfigItem(optname, &opt, default_opt_size));
}
}
// This function is called by the same premises as the CUDT::CUDT(const CUDT&) (copy constructor).
// The intention is to rewrite the part that comprises settings from the socket
// into the group. Note that some of the settings concern group, some others concern
// only target socket, and there are also options that can't be set on a socket.
void CUDTGroup::deriveSettings(CUDT* u)
{
// !!! IMPORTANT !!!
//
// This function shall ONLY be called on a newly created group
// for the sake of the newly accepted socket from the group-enabled listener,
// which is lazy-created for the first ever accepted socket.
// Once the group is created, it should stay with the options
// state as initialized here, and be changeable only in case when
// the option is altered on the group.
// SRTO_RCVSYN
m_bSynRecving = u->m_config.bSynRecving;
// SRTO_SNDSYN
m_bSynSending = u->m_config.bSynSending;
// SRTO_RCVTIMEO
m_iRcvTimeOut = u->m_config.iRcvTimeOut;
// SRTO_SNDTIMEO
m_iSndTimeOut = u->m_config.iSndTimeOut;
// SRTO_GROUPMINSTABLETIMEO
m_uOPT_MinStabilityTimeout_us = 1000 * u->m_config.uMinStabilityTimeout_ms;
// Ok, this really is disgusting, but there's only one way
// to properly do it. Would be nice to have some more universal
// connection between an option symbolic name and the internals
// in CUDT class, but until this is done, since now every new
// option will have to be handled both in the CUDT::setOpt/getOpt
// functions, and here as well.
// This is about moving options from listener to the group,
// to be potentially replicated on the socket. So both pre
// and post options apply.
#define IM(option, field) importOption(m_config, option, u->m_config.field)
#define IMF(option, field) importOption(m_config, option, u->field)
IM(SRTO_MSS, iMSS);
IM(SRTO_FC, iFlightFlagSize);
// Nonstandard
importOption(m_config, SRTO_SNDBUF, u->m_config.iSndBufSize * (u->m_config.iMSS - CPacket::UDP_HDR_SIZE));
importOption(m_config, SRTO_RCVBUF, u->m_config.iRcvBufSize * (u->m_config.iMSS - CPacket::UDP_HDR_SIZE));
IM(SRTO_LINGER, Linger);
IM(SRTO_UDP_SNDBUF, iUDPSndBufSize);
IM(SRTO_UDP_RCVBUF, iUDPRcvBufSize);
// SRTO_RENDEZVOUS: impossible to have it set on a listener socket.
// SRTO_SNDTIMEO/RCVTIMEO: groupwise setting
IM(SRTO_CONNTIMEO, tdConnTimeOut);
IM(SRTO_DRIFTTRACER, bDriftTracer);
// Reuseaddr: true by default and should only be true.
IM(SRTO_MAXBW, llMaxBW);
IM(SRTO_INPUTBW, llInputBW);
IM(SRTO_MININPUTBW, llMinInputBW);
IM(SRTO_OHEADBW, iOverheadBW);
IM(SRTO_IPTOS, iIpToS);
IM(SRTO_IPTTL, iIpTTL);
IM(SRTO_TSBPDMODE, bTSBPD);
IM(SRTO_RCVLATENCY, iRcvLatency);
IM(SRTO_PEERLATENCY, iPeerLatency);
IM(SRTO_SNDDROPDELAY, iSndDropDelay);
IM(SRTO_PAYLOADSIZE, zExpPayloadSize);
IMF(SRTO_TLPKTDROP, m_bTLPktDrop);
importOption(m_config, SRTO_STREAMID, u->m_config.sStreamName.str());
IM(SRTO_MESSAGEAPI, bMessageAPI);
IM(SRTO_NAKREPORT, bRcvNakReport);
IM(SRTO_MINVERSION, uMinimumPeerSrtVersion);
IM(SRTO_ENFORCEDENCRYPTION, bEnforcedEnc);
IM(SRTO_IPV6ONLY, iIpV6Only);
IM(SRTO_PEERIDLETIMEO, iPeerIdleTimeout_ms);
importOption(m_config, SRTO_PACKETFILTER, u->m_config.sPacketFilterConfig.str());
importOption(m_config, SRTO_PBKEYLEN, u->m_pCryptoControl->KeyLen());
// Passphrase is empty by default. Decipher the passphrase and
// store as passphrase option
if (u->m_config.CryptoSecret.len)
{
string password((const char*)u->m_config.CryptoSecret.str, u->m_config.CryptoSecret.len);
m_config.push_back(ConfigItem(SRTO_PASSPHRASE, password.c_str(), (int)password.size()));
}
IM(SRTO_KMREFRESHRATE, uKmRefreshRatePkt);
IM(SRTO_KMPREANNOUNCE, uKmPreAnnouncePkt);
string cc = u->m_CongCtl.selected_name();
if (cc != "live")
{
m_config.push_back(ConfigItem(SRTO_CONGESTION, cc.c_str(), (int)cc.size()));
}
// NOTE: This is based on information extracted from the "semi-copy-constructor" of CUDT class.
// Here should be handled all things that are options that modify the socket, but not all options
// are assigned to configurable items.
#undef IM
#undef IMF
}
bool CUDTGroup::applyFlags(uint32_t flags, HandshakeSide)
{
const bool synconmsg = IsSet(flags, SRT_GFLAG_SYNCONMSG);
if (synconmsg)
{
LOGP(gmlog.Error, "GROUP: requested sync on msgno - not supported.");
return false;
}
return true;
}
template <class Type>
struct Value
{
static int fill(void* optval, int, Type value)
{
// XXX assert size >= sizeof(Type) ?
*(Type*)optval = value;
return sizeof(Type);
}
};
template <>
inline int Value<std::string>::fill(void* optval, int len, std::string value)
{
if (size_t(len) < value.size())
return 0;
memcpy(optval, value.c_str(), value.size());
return (int) value.size();
}
template <class V>
inline int fillValue(void* optval, int len, V value)
{
return Value<V>::fill(optval, len, value);
}
static bool getOptDefault(SRT_SOCKOPT optname, void* pw_optval, int& w_optlen)
{
static const linger def_linger = {1, CSrtConfig::DEF_LINGER_S};
switch (optname)
{
default:
return false;
#define RD(value) \
w_optlen = fillValue((pw_optval), w_optlen, value); \
break
case SRTO_KMSTATE:
case SRTO_SNDKMSTATE:
case SRTO_RCVKMSTATE:
RD(SRT_KM_S_UNSECURED);
case SRTO_PBKEYLEN:
RD(16);
case SRTO_MSS:
RD(CSrtConfig::DEF_MSS);
case SRTO_SNDSYN:
RD(true);
case SRTO_RCVSYN:
RD(true);
case SRTO_ISN:
RD(SRT_SEQNO_NONE);
case SRTO_FC:
RD(CSrtConfig::DEF_FLIGHT_SIZE);
case SRTO_SNDBUF:
case SRTO_RCVBUF:
w_optlen = fillValue((pw_optval), w_optlen, CSrtConfig::DEF_BUFFER_SIZE * (CSrtConfig::DEF_MSS - CPacket::UDP_HDR_SIZE));
break;
case SRTO_LINGER:
RD(def_linger);
case SRTO_UDP_SNDBUF:
case SRTO_UDP_RCVBUF:
RD(CSrtConfig::DEF_UDP_BUFFER_SIZE);
case SRTO_RENDEZVOUS:
RD(false);
case SRTO_SNDTIMEO:
RD(-1);
case SRTO_RCVTIMEO:
RD(-1);
case SRTO_REUSEADDR:
RD(true);
case SRTO_MAXBW:
RD(int64_t(-1));
case SRTO_INPUTBW:
RD(int64_t(-1));
case SRTO_OHEADBW:
RD(0);
case SRTO_STATE:
RD(SRTS_INIT);
case SRTO_EVENT:
RD(0);
case SRTO_SNDDATA:
RD(0);
case SRTO_RCVDATA:
RD(0);
case SRTO_IPTTL:
RD(0);
case SRTO_IPTOS:
RD(0);
case SRTO_SENDER:
RD(false);
case SRTO_TSBPDMODE:
RD(false);
case SRTO_LATENCY:
case SRTO_RCVLATENCY:
case SRTO_PEERLATENCY:
RD(SRT_LIVE_DEF_LATENCY_MS);
case SRTO_TLPKTDROP:
RD(true);
case SRTO_SNDDROPDELAY:
RD(-1);
case SRTO_NAKREPORT:
RD(true);
case SRTO_VERSION:
RD(SRT_DEF_VERSION);
case SRTO_PEERVERSION:
RD(0);
case SRTO_CONNTIMEO:
RD(-1);
case SRTO_DRIFTTRACER:
RD(true);
case SRTO_MINVERSION:
RD(0);
case SRTO_STREAMID:
RD(std::string());
case SRTO_CONGESTION:
RD(std::string());
case SRTO_MESSAGEAPI:
RD(true);
case SRTO_PAYLOADSIZE:
RD(0);
case SRTO_GROUPMINSTABLETIMEO:
RD(CSrtConfig::COMM_DEF_MIN_STABILITY_TIMEOUT_MS);
}
#undef RD
return true;
}
void CUDTGroup::getOpt(SRT_SOCKOPT optname, void* pw_optval, int& w_optlen)
{
// Options handled in group
switch (optname)
{
case SRTO_RCVSYN:
*(bool*)pw_optval = m_bSynRecving;
w_optlen = sizeof(bool);
return;
case SRTO_SNDSYN:
*(bool*)pw_optval = m_bSynSending;
w_optlen = sizeof(bool);
return;
default:; // pass on
}
// XXX Suspicous: may require locking of GlobControlLock
// to prevent from deleting a socket in the meantime.
// Deleting a socket requires removing from the group first,
// so after GroupLock this will be either already NULL or
// a valid socket that will only be closed after time in
// the GC, so this is likely safe like all other API functions.
CUDTSocket* ps = 0;
{
// In sockets. All sockets should have all options
// set the same and should represent the group state
// well enough. If there are no sockets, just use default.
// Group lock to protect the container itself.
// Once a socket is extracted, we state it cannot be
// closed without the group send/recv function or closing
// being involved.
ScopedLock lg(m_GroupLock);
if (m_Group.empty())
{
if (!getOptDefault(optname, (pw_optval), (w_optlen)))
throw CUDTException(MJ_NOTSUP, MN_INVAL, 0);
return;
}
ps = m_Group.begin()->ps;
// Release the lock on the group, as it's not necessary,
// as well as it might cause a deadlock when combined
// with the others.
}
if (!ps)
throw CUDTException(MJ_NOTSUP, MN_INVAL, 0);
return ps->core().getOpt(optname, (pw_optval), (w_optlen));
}
SRT_SOCKSTATUS CUDTGroup::getStatus()
{
typedef vector<pair<SRTSOCKET, SRT_SOCKSTATUS> > states_t;
states_t states;
{
ScopedLock cg(m_GroupLock);
for (gli_t gi = m_Group.begin(); gi != m_Group.end(); ++gi)
{
switch (gi->sndstate)
{
// Check only sndstate. If this machine is ONLY receiving,
// then rcvstate will turn into SRT_GST_RUNNING, while
// sndstate will remain SRT_GST_IDLE, but still this may only
// happen if the socket is connected.
case SRT_GST_IDLE:
case SRT_GST_RUNNING:
states.push_back(make_pair(gi->id, SRTS_CONNECTED));
break;
case SRT_GST_BROKEN:
states.push_back(make_pair(gi->id, SRTS_BROKEN));
break;
default: // (pending, or whatever will be added in future)
{
// TEMPORARY make a node to note a socket to be checked afterwards
states.push_back(make_pair(gi->id, SRTS_NONEXIST));
}
}
}
}
SRT_SOCKSTATUS pending_state = SRTS_NONEXIST;
for (states_t::iterator i = states.begin(); i != states.end(); ++i)
{
// If at least one socket is connected, the state is connected.
if (i->second == SRTS_CONNECTED)
return SRTS_CONNECTED;
// Second level - pick up the state
if (i->second == SRTS_NONEXIST)
{
// Otherwise find at least one socket, which's state isn't broken.
i->second = m_Global.getStatus(i->first);
if (pending_state == SRTS_NONEXIST)
pending_state = i->second;
}
}
// Return that state as group state
if (pending_state != SRTS_NONEXIST) // did call getStatus at least once and it didn't return NOEXIST
return pending_state;
// If none found, return SRTS_BROKEN.
return SRTS_BROKEN;
}
// [[using locked(m_GroupLock)]];
void CUDTGroup::syncWithSocket(const CUDT& core, const HandshakeSide side)
{
if (side == HSD_RESPONDER)
{
// On the listener side you should synchronize ISN with the incoming
// socket, which is done immediately after creating the socket and
// adding it to the group. On the caller side the ISN is defined in
// the group directly, before any member socket is created.
set_currentSchedSequence(core.ISN());
}
// XXX
// Might need further investigation as to whether this isn't
// wrong for some cases. By having this -1 here the value will be
// laziliy set from the first reading one. It is believed that
// it covers all possible scenarios, that is:
//
// - no readers - no problem!
// - have some readers and a new is attached - this is set already
// - connect multiple links, but none has read yet - you'll be the first.
//
// Previous implementation used setting to: core.m_iPeerISN
resetInitialRxSequence();
// Get the latency (possibly fixed against the opposite side)
// from the first socket (core.m_iTsbPdDelay_ms),
// and set it on the current socket.
set_latency(core.m_iTsbPdDelay_ms * int64_t(1000));
}
void CUDTGroup::close()
{
// Close all descriptors, then delete the group.
vector<SRTSOCKET> ids;
{
ScopedLock glob(CUDT::uglobal().m_GlobControlLock);
ScopedLock g(m_GroupLock);
m_bClosing = true;
// Copy the list of IDs into the array.
for (gli_t ig = m_Group.begin(); ig != m_Group.end(); ++ig)
{
ids.push_back(ig->id);
// Immediately cut ties to this group.
// Just for a case, redispatch the socket, to stay safe.
CUDTSocket* s = CUDT::uglobal().locateSocket_LOCKED(ig->id);
if (!s)
{
HLOGC(smlog.Debug, log << "group/close: IPE(NF): group member @" << ig->id << " already deleted");
continue;
}
// Make the socket closing BEFORE withdrawing its group membership
// because a socket created as a group member cannot be valid
// without the group.
// This is not true in case of non-managed groups, which
// only collect sockets, but also non-managed groups should not
// use common group buffering and tsbpd. Also currently there are
// no other groups than managed one.
s->setClosing();
s->m_GroupOf = NULL;
s->m_GroupMemberData = NULL;
HLOGC(smlog.Debug, log << "group/close: CUTTING OFF @" << ig->id << " (found as @" << s->m_SocketID << ") from the group");
}
// After all sockets that were group members have their ties cut,
// the container can be cleared. Note that sockets won't be now
// removing themselves from the group when closing because they
// are unaware of being group members.
m_Group.clear();
m_PeerGroupID = -1;
set<int> epollid;
{
// Global EPOLL lock must be applied to access any socket's epoll set.
// This is a set of all epoll ids subscribed to it.
ScopedLock elock (CUDT::uglobal().m_EPoll.m_EPollLock);
epollid = m_sPollID; // use move() in C++11
m_sPollID.clear();
}
int no_events = 0;
for (set<int>::iterator i = epollid.begin(); i != epollid.end(); ++i)
{
HLOGC(smlog.Debug, log << "close: CLEARING subscription on E" << (*i) << " of $" << id());
try
{
CUDT::uglobal().m_EPoll.update_usock(*i, id(), &no_events);
}
catch (...)
{
// May catch an API exception, but this isn't an API call to be interrupted.
}
HLOGC(smlog.Debug, log << "close: removing E" << (*i) << " from back-subscribers of $" << id());
}
// NOW, the m_GroupLock is released, then m_GlobControlLock.
// The below code should work with no locks and execute socket
// closing.
}
HLOGC(gmlog.Debug, log << "grp/close: closing $" << m_GroupID << ", closing first " << ids.size() << " sockets:");
// Close all sockets with unlocked GroupLock
for (vector<SRTSOCKET>::iterator i = ids.begin(); i != ids.end(); ++i)
{
try
{
CUDT::uglobal().close(*i);
}
catch (CUDTException&)
{
HLOGC(gmlog.Debug, log << "grp/close: socket @" << *i << " is likely closed already, ignoring");
}
}
HLOGC(gmlog.Debug, log << "grp/close: closing $" << m_GroupID << ": sockets closed, clearing the group:");
// Lock the group again to clear the group data
{
ScopedLock g(m_GroupLock);
if (!m_Group.empty())
{
LOGC(gmlog.Error, log << "grp/close: IPE - after requesting to close all members, still " << m_Group.size()
<< " lingering members!");
m_Group.clear();
}
// This takes care of the internal part.
// The external part will be done in Global (CUDTUnited)
}
// Release blocked clients
// XXX This looks like a dead code. Group receiver functions
// do not use any lock on m_RcvDataLock, it is likely a remainder
// of the old, internal impementation.
// CSync::lock_notify_one(m_RcvDataCond, m_RcvDataLock);
}
// [[using locked(m_Global->m_GlobControlLock)]]
// [[using locked(m_GroupLock)]]
void CUDTGroup::send_CheckValidSockets()
{
vector<gli_t> toremove;
for (gli_t d = m_Group.begin(), d_next = d; d != m_Group.end(); d = d_next)
{
++d_next; // it's now safe to erase d
CUDTSocket* revps = m_Global.locateSocket_LOCKED(d->id);
if (revps != d->ps)
{
// Note: the socket might STILL EXIST, just in the trash, so
// it can't be found by locateSocket. But it can still be bound
// to the group. Just mark it broken from upside so that the
// internal sending procedures will skip it. Removal from the
// group will happen in GC, which will both remove from
// group container and cut backward links to the group.
HLOGC(gmlog.Debug, log << "group/send_CheckValidSockets: socket @" << d->id << " is no longer valid, setting BROKEN in $" << id());
d->sndstate = SRT_GST_BROKEN;
d->rcvstate = SRT_GST_BROKEN;
}
}
}
int CUDTGroup::send(const char* buf, int len, SRT_MSGCTRL& w_mc)
{
switch (m_type)
{
default:
LOGC(gslog.Error, log << "CUDTGroup::send: not implemented for type #" << m_type);
throw CUDTException(MJ_SETUP, MN_INVAL, 0);
case SRT_GTYPE_BROADCAST:
return sendBroadcast(buf, len, (w_mc));
case SRT_GTYPE_BACKUP:
return sendBackup(buf, len, (w_mc));
/* to be implemented
case SRT_GTYPE_BALANCING:
return sendBalancing(buf, len, (w_mc));
case SRT_GTYPE_MULTICAST:
return sendMulticast(buf, len, (w_mc));
*/
}
}
int CUDTGroup::sendBroadcast(const char* buf, int len, SRT_MSGCTRL& w_mc)
{
// Avoid stupid errors in the beginning.
if (len <= 0)
{
throw CUDTException(MJ_NOTSUP, MN_INVAL, 0);
}
// NOTE: This is a "vector of list iterators". Every element here
// is an iterator to another container.
// Note that "list" is THE ONLY container in standard C++ library,
// for which NO ITERATORS ARE INVALIDATED after a node at particular
// iterator has been removed, except for that iterator itself.
vector<SRTSOCKET> wipeme;
vector<gli_t> idleLinks;
vector<SRTSOCKET> pendingSockets; // need sock ids as it will be checked out of lock
int32_t curseq = SRT_SEQNO_NONE; // The seqno of the first packet of this message.
int32_t nextseq = SRT_SEQNO_NONE; // The seqno of the first packet of next message.
int rstat = -1;
int stat = 0;
SRT_ATR_UNUSED CUDTException cx(MJ_SUCCESS, MN_NONE, 0);
vector<gli_t> activeLinks;
// First, acquire GlobControlLock to make sure all member sockets still exist
enterCS(m_Global.m_GlobControlLock);
ScopedLock guard(m_GroupLock);
if (m_bClosing)
{
leaveCS(m_Global.m_GlobControlLock);
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
}
// Now, still under lock, check if all sockets still can be dispatched
// LOCKED: GlobControlLock, GroupLock (RIGHT ORDER!)
send_CheckValidSockets();
leaveCS(m_Global.m_GlobControlLock);
// LOCKED: GroupLock (only)
// Since this moment GlobControlLock may only be locked if GroupLock is unlocked first.
if (m_bClosing)
{
// No temporary locks here. The group lock is scoped.
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
}
// This simply requires the payload to be sent through every socket in the group
for (gli_t d = m_Group.begin(); d != m_Group.end(); ++d)
{
if (d->sndstate != SRT_GST_BROKEN)
{
// Check the socket state prematurely in order not to uselessly
// send over a socket that is broken.
CUDT* const pu = (d->ps)
? &d->ps->core()
: NULL;
if (!pu || pu->m_bBroken)
{
HLOGC(gslog.Debug,
log << "grp/sendBroadcast: socket @" << d->id << " detected +Broken - transit to BROKEN");
d->sndstate = SRT_GST_BROKEN;
d->rcvstate = SRT_GST_BROKEN;
}
}
// Check socket sndstate before sending
if (d->sndstate == SRT_GST_BROKEN)
{
HLOGC(gslog.Debug,
log << "grp/sendBroadcast: socket in BROKEN state: @" << d->id
<< ", sockstatus=" << SockStatusStr(d->ps ? d->ps->getStatus() : SRTS_NONEXIST));
wipeme.push_back(d->id);
continue;
}
if (d->sndstate == SRT_GST_IDLE)
{
SRT_SOCKSTATUS st = SRTS_NONEXIST;
if (d->ps)
st = d->ps->getStatus();
// If the socket is already broken, move it to broken.
if (int(st) >= int(SRTS_BROKEN))
{
HLOGC(gslog.Debug,
log << "CUDTGroup::send.$" << id() << ": @" << d->id << " became " << SockStatusStr(st)
<< ", WILL BE CLOSED.");
wipeme.push_back(d->id);
continue;
}
if (st != SRTS_CONNECTED)
{
HLOGC(gslog.Debug,
log << "CUDTGroup::send. @" << d->id << " is still " << SockStatusStr(st) << ", skipping.");
pendingSockets.push_back(d->id);
continue;
}
HLOGC(gslog.Debug, log << "grp/sendBroadcast: socket in IDLE state: @" << d->id << " - will activate it");
// This is idle, we'll take care of them next time
// Might be that:
// - this socket is idle, while some NEXT socket is running
// - we need at least one running socket to work BEFORE activating the idle one.
// - if ALL SOCKETS ARE IDLE, then we simply activate the first from the list,
// and all others will be activated using the ISN from the first one.
idleLinks.push_back(d);
continue;
}
if (d->sndstate == SRT_GST_RUNNING)
{
HLOGC(gslog.Debug,
log << "grp/sendBroadcast: socket in RUNNING state: @" << d->id << " - will send a payload");
activeLinks.push_back(d);
continue;
}
HLOGC(gslog.Debug,
log << "grp/sendBroadcast: socket @" << d->id << " not ready, state: " << StateStr(d->sndstate) << "("
<< int(d->sndstate) << ") - NOT sending, SET AS PENDING");
pendingSockets.push_back(d->id);
}
vector<Sendstate> sendstates;
if (w_mc.srctime == 0)
w_mc.srctime = count_microseconds(steady_clock::now().time_since_epoch());
for (vector<gli_t>::iterator snd = activeLinks.begin(); snd != activeLinks.end(); ++snd)
{
gli_t d = *snd;
int erc = 0; // success
// Remaining sndstate is SRT_GST_RUNNING. Send a payload through it.
try
{
// This must be wrapped in try-catch because on error it throws an exception.
// Possible return values are only 0, in case when len was passed 0, or a positive
// >0 value that defines the size of the data that it has sent, that is, in case
// of Live mode, equal to 'len'.
stat = d->ps->core().sendmsg2(buf, len, (w_mc));
}
catch (CUDTException& e)
{
cx = e;
stat = -1;
erc = e.getErrorCode();
}
if (stat != -1)
{
curseq = w_mc.pktseq;
nextseq = d->ps->core().schedSeqNo();
}
const Sendstate cstate = {d->id, &*d, stat, erc};
sendstates.push_back(cstate);
d->sndresult = stat;
d->laststatus = d->ps->getStatus();
}
// Ok, we have attempted to send a payload over all links
// that are currently in the RUNNING state. We know that at
// least one is successful if we have non-default curseq value.
// Here we need to activate all links that are found as IDLE.
// Some portion of logical exclusions:
//
// - sockets that were broken in the beginning are already wiped out
// - broken sockets are checked first, so they can't be simultaneously idle
// - idle sockets can't get broken because there's no operation done on them
// - running sockets are the only one that could change sndstate here
// - running sockets can either remain running or turn to broken
// In short: Running and Broken sockets can't become idle,
// although Running sockets can become Broken.
// There's no certainty here as to whether at least one link was
// running and it has successfully performed the operation.
// Might have even happened that we had 2 running links that
// got broken and 3 other links so far in idle sndstate that just connected
// at that very moment. In this case we have 3 idle links to activate,
// but there is no sequence base to overwrite their ISN with. If this
// happens, then the first link that should be activated goes with
// whatever ISN it has, whereas every next idle link should use that
// exactly ISN.
//
// If it has additionally happened that the first link got broken at
// that very moment of sending, the second one has a chance to succeed
// and therefore take over the leading role in setting the ISN. If the
// second one fails, too, then the only remaining idle link will simply
// go with its own original sequence.
// On the opposite side, if the first packet arriving looks like a jump over,
// the corresponding LOSSREPORT is sent. For packets that are truly lost,
// the sender retransmits them, for packets that before ISN, DROPREQ is sent.
// Now we can go to the idle links and attempt to send the payload
// also over them.
// TODO: { sendBroadcast_ActivateIdleLinks
for (vector<gli_t>::iterator i = idleLinks.begin(); i != idleLinks.end(); ++i)
{
gli_t d = *i;
if (!d->ps->m_GroupOf)
continue;
int erc = 0;
int lastseq = d->ps->core().schedSeqNo();
if (curseq != SRT_SEQNO_NONE && curseq != lastseq)
{
HLOGC(gslog.Debug,
log << "grp/sendBroadcast: socket @" << d->id << ": override snd sequence %" << lastseq << " with %"
<< curseq << " (diff by " << CSeqNo::seqcmp(curseq, lastseq)
<< "); SENDING PAYLOAD: " << BufferStamp(buf, len));
d->ps->core().overrideSndSeqNo(curseq);
}
else
{
HLOGC(gslog.Debug,
log << "grp/sendBroadcast: socket @" << d->id << ": sequence remains with original value: %"
<< lastseq << "; SENDING PAYLOAD " << BufferStamp(buf, len));
}
// Now send and check the status
// The link could have got broken
try
{
stat = d->ps->core().sendmsg2(buf, len, (w_mc));
}
catch (CUDTException& e)
{
cx = e;
stat = -1;
erc = e.getErrorCode();
}
if (stat != -1)
{
d->sndstate = SRT_GST_RUNNING;
// Note: this will override the sequence number
// for all next iterations in this loop.
curseq = w_mc.pktseq;
nextseq = d->ps->core().schedSeqNo();
HLOGC(gslog.Debug,
log << "@" << d->id << ":... sending SUCCESSFUL %" << curseq << " MEMBER STATUS: RUNNING");
}
d->sndresult = stat;
d->laststatus = d->ps->getStatus();
const Sendstate cstate = {d->id, &*d, stat, erc};
sendstates.push_back(cstate);
}
if (nextseq != SRT_SEQNO_NONE)
{
HLOGC(gslog.Debug,
log << "grp/sendBroadcast: $" << id() << ": updating current scheduling sequence %" << nextseq);
m_iLastSchedSeqNo = nextseq;
}
// }
// { send_CheckBrokenSockets()
if (!pendingSockets.empty())
{
HLOGC(gslog.Debug, log << "grp/sendBroadcast: found pending sockets, polling them.");
// These sockets if they are in pending state, they should be added to m_SndEID
// at the connecting stage.
CEPoll::fmap_t sready;
if (m_Global.m_EPoll.empty(*m_SndEpolld))
{
// Sanity check - weird pending reported.
LOGC(gslog.Error,
log << "grp/sendBroadcast: IPE: reported pending sockets, but EID is empty - wiping pending!");
copy(pendingSockets.begin(), pendingSockets.end(), back_inserter(wipeme));
}
else
{
{
InvertedLock ug(m_GroupLock);
THREAD_PAUSED();
m_Global.m_EPoll.swait(
*m_SndEpolld, sready, 0, false /*report by retval*/); // Just check if anything happened
THREAD_RESUMED();
}
if (m_bClosing)
{
// No temporary locks here. The group lock is scoped.
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
}
HLOGC(gslog.Debug, log << "grp/sendBroadcast: RDY: " << DisplayEpollResults(sready));
// sockets in EX: should be moved to wipeme.
for (vector<SRTSOCKET>::iterator i = pendingSockets.begin(); i != pendingSockets.end(); ++i)
{
if (CEPoll::isready(sready, *i, SRT_EPOLL_ERR))
{
HLOGC(gslog.Debug,
log << "grp/sendBroadcast: Socket @" << (*i) << " reported FAILURE - moved to wiped.");
// Failed socket. Move d to wipeme. Remove from eid.
wipeme.push_back(*i);
int no_events = 0;
m_Global.m_EPoll.update_usock(m_SndEID, *i, &no_events);
}
}
// After that, all sockets that have been reported
// as ready to write should be removed from EID. This
// will also remove those sockets that have been added
// as redundant links at the connecting stage and became
// writable (connected) before this function had a chance
// to check them.
m_Global.m_EPoll.clear_ready_usocks(*m_SndEpolld, SRT_EPOLL_CONNECT);
}
}
// Re-check after the waiting lock has been reacquired
if (m_bClosing)
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
send_CloseBrokenSockets(wipeme);
// Re-check after the waiting lock has been reacquired
if (m_bClosing)
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
// }
// { sendBroadcast_CheckBlockedLinks()
// Alright, we've made an attempt to send a packet over every link.
// Every operation was done through a non-blocking attempt, so
// links where sending was blocked have SRT_EASYNCSND error.
// Links that were successful, have the len value in state.
// First thing then, find out if at least one link was successful.
// The first successful link sets the sequence value,
// the following links derive it. This might be also the first idle
// link with its random-generated ISN, if there were no active links.
vector<SocketData*> successful, blocked;
// This iteration of the state will simply
// qualify the remaining sockets into three categories:
//
// - successful (we only need to know if at least one did)
// - blocked - if none succeeded, but some blocked, POLL & RETRY.
// - wipeme - sending failed by any other reason than blocking, remove.
// Now - sendstates contain directly sockets.
// In order to update members, you need to have locked:
// - GlobControlLock to prevent sockets from disappearing or being closed
// - then GroupLock to latch the validity of m_GroupMemberData field.
{
{
InvertedLock ung (m_GroupLock);
enterCS(CUDT::uglobal().m_GlobControlLock);
HLOGC(gslog.Debug, log << "grp/sendBroadcast: Locked GlobControlLock, locking back GroupLock");
}
// Under this condition, as an unlock-lock cycle was done on m_GroupLock,
// the Sendstate::it field shall not be used here!
for (vector<Sendstate>::iterator is = sendstates.begin(); is != sendstates.end(); ++is)
{
CUDTSocket* ps = CUDT::uglobal().locateSocket_LOCKED(is->id);
// Is the socket valid? If not, simply SKIP IT. Nothing to be done with it,
// it's already deleted.
if (!ps)
continue;
// Is the socket still group member? If not, SKIP IT. It could only be taken ownership
// by being explicitly closed and so it's deleted from the container.
if (!ps->m_GroupOf)
continue;
// Now we are certain that m_GroupMemberData is valid.
SocketData* d = ps->m_GroupMemberData;
if (is->stat == len)
{
HLOGC(gslog.Debug,
log << "SEND STATE link [" << (is - sendstates.begin()) << "]: SUCCESSFULLY sent " << len
<< " bytes");
// Successful.
successful.push_back(d);
rstat = is->stat;
continue;
}
// Remaining are only failed. Check if again.
if (is->code == SRT_EASYNCSND)
{
blocked.push_back(d);
continue;
}
#if ENABLE_HEAVY_LOGGING
string errmsg = cx.getErrorString();
LOGC(gslog.Debug,
log << "SEND STATE link [" << (is - sendstates.begin()) << "]: FAILURE (result:" << is->stat
<< "): " << errmsg << ". Setting this socket broken status.");
#endif
// Turn this link broken
d->sndstate = SRT_GST_BROKEN;
}
// Now you can leave GlobControlLock, while GroupLock is still locked.
leaveCS(CUDT::uglobal().m_GlobControlLock);
}
// Re-check after the waiting lock has been reacquired
if (m_bClosing)
{
HLOGC(gslog.Debug, log << "grp/sendBroadcast: GROUP CLOSED, ABANDONING");
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
}
// Good, now let's realize the situation.
// First, check the most optimistic scenario: at least one link succeeded.
bool was_blocked = false;
bool none_succeeded = false;
if (!successful.empty())
{
// Good. All blocked links are now qualified as broken.
// You had your chance, but I can't leave you here,
// there will be no further chance to reattempt sending.
for (vector<SocketData*>::iterator b = blocked.begin(); b != blocked.end(); ++b)
{
(*b)->sndstate = SRT_GST_BROKEN;
}
blocked.clear();
}
else
{
none_succeeded = true;
was_blocked = !blocked.empty();
}
int ercode = 0;
if (was_blocked)
{
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_OUT, false);
if (!m_bSynSending)
{
throw CUDTException(MJ_AGAIN, MN_WRAVAIL, 0);
}
HLOGC(gslog.Debug, log << "grp/sendBroadcast: all blocked, trying to common-block on epoll...");
// XXX TO BE REMOVED. Sockets should be subscribed in m_SndEID at connecting time
// (both srt_connect and srt_accept).
// None was successful, but some were blocked. It means that we
// haven't sent the payload over any link so far, so we still have
// a chance to retry.
int modes = SRT_EPOLL_OUT | SRT_EPOLL_ERR;
for (vector<SocketData*>::iterator b = blocked.begin(); b != blocked.end(); ++b)
{
HLOGC(gslog.Debug,
log << "Will block on blocked socket @" << (*b)->id << " as only blocked socket remained");
CUDT::uglobal().epoll_add_usock_INTERNAL(m_SndEID, (*b)->ps, &modes);
}
int blst = 0;
CEPoll::fmap_t sready;
{
// Lift the group lock for a while, to avoid possible deadlocks.
InvertedLock ug(m_GroupLock);
HLOGC(gslog.Debug, log << "grp/sendBroadcast: blocking on any of blocked sockets to allow sending");
// m_iSndTimeOut is -1 by default, which matches the meaning of waiting forever
THREAD_PAUSED();
blst = m_Global.m_EPoll.swait(*m_SndEpolld, sready, m_iSndTimeOut);
THREAD_RESUMED();
// NOTE EXCEPTIONS:
// - EEMPTY: won't happen, we have explicitly added sockets to EID here.
// - XTIMEOUT: will be propagated as this what should be reported to API
// This is the only reason why here the errors are allowed to be handled
// by exceptions.
}
// Re-check after the waiting lock has been reacquired
if (m_bClosing)
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
if (blst == -1)
{
int rno;
ercode = srt_getlasterror(&rno);
}
else
{
activeLinks.clear();
sendstates.clear();
// Extract gli's from the whole group that have id found in the array.
// LOCKING INFO:
// For the moment of lifting m_GroupLock, some sockets could have been closed.
// But then, we believe they have been also removed from the group container,
// and this requires locking on GroupLock. We can then stafely state that the
// group container contains only existing sockets, at worst broken.
for (gli_t dd = m_Group.begin(); dd != m_Group.end(); ++dd)
{
int rdev = CEPoll::ready(sready, dd->id);
if (rdev & SRT_EPOLL_ERR)
{
dd->sndstate = SRT_GST_BROKEN;
}
else if (rdev & SRT_EPOLL_OUT)
activeLinks.push_back(dd);
}
for (vector<gli_t>::iterator snd = activeLinks.begin(); snd != activeLinks.end(); ++snd)
{
gli_t d = *snd;
int erc = 0; // success
// Remaining sndstate is SRT_GST_RUNNING. Send a payload through it.
try
{
// This must be wrapped in try-catch because on error it throws an exception.
// Possible return values are only 0, in case when len was passed 0, or a positive
// >0 value that defines the size of the data that it has sent, that is, in case
// of Live mode, equal to 'len'.
stat = d->ps->core().sendmsg2(buf, len, (w_mc));
}
catch (CUDTException& e)
{
cx = e;
stat = -1;
erc = e.getErrorCode();
}
if (stat != -1)
curseq = w_mc.pktseq;
const Sendstate cstate = {d->id, &*d, stat, erc};
sendstates.push_back(cstate);
d->sndresult = stat;
d->laststatus = d->ps->getStatus();
}
// This time only check if any were successful.
// All others are wipeme.
// NOTE: m_GroupLock is continuously locked - you can safely use Sendstate::it field.
for (vector<Sendstate>::iterator is = sendstates.begin(); is != sendstates.end(); ++is)
{
if (is->stat == len)
{
// Successful.
successful.push_back(is->mb);
rstat = is->stat;
was_blocked = false;
none_succeeded = false;
continue;
}
#if ENABLE_HEAVY_LOGGING
string errmsg = cx.getErrorString();
HLOGC(gslog.Debug,
log << "... (repeat-waited) sending FAILED (" << errmsg
<< "). Setting this socket broken status.");
#endif
// Turn this link broken
is->mb->sndstate = SRT_GST_BROKEN;
}
}
}
// }
if (none_succeeded)
{
HLOGC(gslog.Debug, log << "grp/sendBroadcast: all links broken (none succeeded to send a payload)");
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_OUT, false);
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_ERR, true);
// Reparse error code, if set.
// It might be set, if the last operation was failed.
// If any operation succeeded, this will not be executed anyway.
CodeMajor major = CodeMajor(ercode ? ercode / 1000 : MJ_CONNECTION);
CodeMinor minor = CodeMinor(ercode ? ercode % 1000 : MN_CONNLOST);
throw CUDTException(major, minor, 0);
}
// Now that at least one link has succeeded, update sending stats.
m_stats.sent.count(len);
// Pity that the blocking mode only determines as to whether this function should
// block or not, but the epoll flags must be updated regardless of the mode.
// Now fill in the socket table. Check if the size is enough, if not,
// then set the pointer to NULL and set the correct size.
// Note that list::size() is linear time, however this shouldn't matter,
// as with the increased number of links in the redundancy group the
// impossibility of using that many of them grows exponentally.
size_t grpsize = m_Group.size();
if (w_mc.grpdata_size < grpsize)
{
w_mc.grpdata = NULL;
}
size_t i = 0;
bool ready_again = false;
for (gli_t d = m_Group.begin(); d != m_Group.end(); ++d, ++i)
{
if (w_mc.grpdata)
{
// Enough space to fill
copyGroupData(*d, (w_mc.grpdata[i]));
}
// We perform this loop anyway because we still need to check if any
// socket is writable. Note that the group lock will hold any write ready
// updates that are performed just after a single socket update for the
// group, so if any socket is actually ready at the moment when this
// is performed, and this one will result in none-write-ready, this will
// be fixed just after returning from this function.
ready_again = ready_again || d->ps->writeReady();
}
w_mc.grpdata_size = i;
if (!ready_again)
{
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_OUT, false);
}
return rstat;
}
int CUDTGroup::getGroupData(SRT_SOCKGROUPDATA* pdata, size_t* psize)
{
if (!psize)
return CUDT::APIError(MJ_NOTSUP, MN_INVAL);
ScopedLock gl(m_GroupLock);
return getGroupData_LOCKED(pdata, psize);
}
// [[using locked(this->m_GroupLock)]]
int CUDTGroup::getGroupData_LOCKED(SRT_SOCKGROUPDATA* pdata, size_t* psize)
{
SRT_ASSERT(psize != NULL);
const size_t size = *psize;
// Rewrite correct size
*psize = m_Group.size();
if (!pdata)
{
return 0;
}
if (m_Group.size() > size)
{
// Not enough space to retrieve the data.
return CUDT::APIError(MJ_NOTSUP, MN_XSIZE);
}
size_t i = 0;
for (gli_t d = m_Group.begin(); d != m_Group.end(); ++d, ++i)
{
copyGroupData(*d, (pdata[i]));
}
return (int)m_Group.size();
}
// [[using locked(this->m_GroupLock)]]
void CUDTGroup::copyGroupData(const CUDTGroup::SocketData& source, SRT_SOCKGROUPDATA& w_target)
{
w_target.id = source.id;
memcpy((&w_target.peeraddr), &source.peer, source.peer.size());
w_target.sockstate = source.laststatus;
w_target.token = source.token;
// In the internal structure the member state
// is one per direction. From the user perspective
// however it is used either in one direction only,
// in which case the one direction that is active
// matters, or in both directions, in which case
// it will be always either both active or both idle.
if (source.sndstate == SRT_GST_RUNNING || source.rcvstate == SRT_GST_RUNNING)
{
w_target.result = 0;
w_target.memberstate = SRT_GST_RUNNING;
}
// Stats can differ per direction only
// when at least in one direction it's ACTIVE.
else if (source.sndstate == SRT_GST_BROKEN || source.rcvstate == SRT_GST_BROKEN)
{
w_target.result = -1;
w_target.memberstate = SRT_GST_BROKEN;
}
else
{
// IDLE or PENDING
w_target.result = 0;
w_target.memberstate = source.sndstate;
}
w_target.weight = source.weight;
}
void CUDTGroup::getGroupCount(size_t& w_size, bool& w_still_alive)
{
ScopedLock gg(m_GroupLock);
// Note: linear time, but no way to avoid it.
// Fortunately the size of the redundancy group is even
// in the craziest possible implementation at worst 4 members long.
size_t group_list_size = 0;
// In managed group, if all sockets made a failure, all
// were removed, so the loop won't even run once. In
// non-managed, simply no socket found here would have a
// connected status.
bool still_alive = false;
for (gli_t gi = m_Group.begin(); gi != m_Group.end(); ++gi)
{
if (gi->laststatus == SRTS_CONNECTED)
{
still_alive = true;
}
++group_list_size;
}
// If no socket is found connected, don't update any status.
w_size = group_list_size;
w_still_alive = still_alive;
}
// [[using locked(m_GroupLock)]]
void CUDTGroup::fillGroupData(SRT_MSGCTRL& w_out, // MSGCTRL to be written
const SRT_MSGCTRL& in // MSGCTRL read from the data-providing socket
)
{
// Preserve the data that will be overwritten by assignment
SRT_SOCKGROUPDATA* grpdata = w_out.grpdata;
size_t grpdata_size = w_out.grpdata_size;
w_out = in; // NOTE: This will write NULL to grpdata and 0 to grpdata_size!
w_out.grpdata = NULL; // Make sure it's done, for any case
w_out.grpdata_size = 0;
// User did not wish to read the group data at all.
if (!grpdata)
{
return;
}
int st = getGroupData_LOCKED((grpdata), (&grpdata_size));
// Always write back the size, no matter if the data were filled.
w_out.grpdata_size = grpdata_size;
if (st == SRT_ERROR)
{
// Keep NULL in grpdata
return;
}
// Write back original data
w_out.grpdata = grpdata;
}
// [[using locked(CUDT::uglobal()->m_GlobControLock)]]
// [[using locked(m_GroupLock)]]
struct FLookupSocketWithEvent_LOCKED
{
CUDTUnited* glob;
int evtype;
FLookupSocketWithEvent_LOCKED(CUDTUnited* g, int event_type)
: glob(g)
, evtype(event_type)
{
}
typedef CUDTSocket* result_type;
pair<CUDTSocket*, bool> operator()(const pair<SRTSOCKET, int>& es)
{
CUDTSocket* so = NULL;
if ((es.second & evtype) == 0)
return make_pair(so, false);
so = glob->locateSocket_LOCKED(es.first);
return make_pair(so, !!so);
}
};
void CUDTGroup::recv_CollectAliveAndBroken(vector<CUDTSocket*>& alive, set<CUDTSocket*>& broken)
{
#if ENABLE_HEAVY_LOGGING
std::ostringstream ds;
ds << "E(" << m_RcvEID << ") ";
#define HCLOG(expr) expr
#else
#define HCLOG(x) if (false) {}
#endif
alive.reserve(m_Group.size());
HLOGC(grlog.Debug, log << "group/recv: Reviewing member sockets for polling");
for (gli_t gi = m_Group.begin(); gi != m_Group.end(); ++gi)
{
if (gi->laststatus == SRTS_CONNECTING)
{
HCLOG(ds << "@" << gi->id << "<pending> ");
continue; // don't read over a failed or pending socket
}
if (gi->laststatus >= SRTS_BROKEN)
{
broken.insert(gi->ps);
}
if (broken.count(gi->ps))
{
HCLOG(ds << "@" << gi->id << "<broken> ");
continue;
}
if (gi->laststatus != SRTS_CONNECTED)
{
HCLOG(ds << "@" << gi->id << "<unstable:" << SockStatusStr(gi->laststatus) << "> ");
// Sockets in this state are ignored. We are waiting until it
// achieves CONNECTING state, then it's added to write.
// Or gets broken and closed in the next step.
continue;
}
// Don't skip packets that are ahead because if we have a situation
// that all links are either "elephants" (do not report read readiness)
// and "kangaroos" (have already delivered an ahead packet) then
// omitting kangaroos will result in only elephants to be polled for
// reading. Due to the strict timing requirements and ensurance that
// TSBPD on every link will result in exactly the same delivery time
// for a packet of given sequence, having an elephant and kangaroo in
// one cage means that the elephant is simply a broken or half-broken
// link (the data are not delivered, but it will get repaired soon,
// enough for SRT to maintain the connection, but it will still drop
// packets that didn't arrive in time), in both cases it may
// potentially block the reading for an indefinite time, while
// simultaneously a kangaroo might be a link that got some packets
// dropped, but then it's still capable to deliver packets on time.
// Note that gi->id might be a socket that was previously being polled
// on write, when it's attempting to connect, but now it's connected.
// This will update the socket with the new event set.
alive.push_back(gi->ps);
HCLOG(ds << "@" << gi->id << "[READ] ");
}
HLOGC(grlog.Debug, log << "group/recv: " << ds.str() << " --> EPOLL/SWAIT");
#undef HCLOG
}
vector<CUDTSocket*> CUDTGroup::recv_WaitForReadReady(const vector<CUDTSocket*>& aliveMembers, set<CUDTSocket*>& w_broken)
{
if (aliveMembers.empty())
{
LOGC(grlog.Error, log << "group/recv: all links broken");
throw CUDTException(MJ_CONNECTION, MN_NOCONN, 0);
}
for (vector<CUDTSocket*>::const_iterator i = aliveMembers.begin(); i != aliveMembers.end(); ++i)
{
// NOT using the official srt_epoll_add_usock because this will do socket dispatching,
// which requires lock on m_GlobControlLock, while this lock cannot be applied without
// first unlocking m_GroupLock.
const int read_modes = SRT_EPOLL_IN | SRT_EPOLL_ERR;
CUDT::uglobal().epoll_add_usock_INTERNAL(m_RcvEID, *i, &read_modes);
}
// Here we need to make an additional check.
// There might be a possibility that all sockets that
// were added to the reader group, are ahead. At least
// surely we don't have a situation that any link contains
// an ahead-read subsequent packet, because GroupCheckPacketAhead
// already handled that case.
//
// What we can have is that every link has:
// - no known seq position yet (is not registered in the position map yet)
// - the position equal to the latest delivered sequence
// - the ahead position
// Now the situation is that we don't have any packets
// waiting for delivery so we need to wait for any to report one.
// The non-blocking mode would need to simply check the readiness
// with only immediate report, and read-readiness would have to
// be done in background.
// In blocking mode, use m_iRcvTimeOut, which's default value -1
// means to block indefinitely, also in swait().
// In non-blocking mode use 0, which means to always return immediately.
int timeout = m_bSynRecving ? m_iRcvTimeOut : 0;
int nready = 0;
// Poll on this descriptor until reading is available, indefinitely.
CEPoll::fmap_t sready;
// GlobControlLock is required for dispatching the sockets.
// Therefore it must be applied only when GroupLock is off.
{
// This call may wait indefinite time, so GroupLock must be unlocked.
InvertedLock ung (m_GroupLock);
THREAD_PAUSED();
nready = m_Global.m_EPoll.swait(*m_RcvEpolld, sready, timeout, false /*report by retval*/);
THREAD_RESUMED();
// HERE GlobControlLock is locked first, then GroupLock is applied back
enterCS(CUDT::uglobal().m_GlobControlLock);
}
// BOTH m_GlobControlLock AND m_GroupLock are locked here.
HLOGC(grlog.Debug, log << "group/recv: " << nready << " RDY: " << DisplayEpollResults(sready));
if (nready == 0)
{
// GlobControlLock is applied manually, so unlock manually.
// GroupLock will be unlocked as per scope.
leaveCS(CUDT::uglobal().m_GlobControlLock);
// This can only happen when 0 is passed as timeout and none is ready.
// And 0 is passed only in non-blocking mode. So this is none ready in
// non-blocking mode.
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_IN, false);
throw CUDTException(MJ_AGAIN, MN_RDAVAIL, 0);
}
// Handle sockets of pending connection and with errors.
// Nice to have something like:
// broken = FilterIf(sready, [] (auto s)
// { return s.second == SRT_EPOLL_ERR && (auto cs = g->locateSocket(s.first, ERH_RETURN))
// ? {cs, true}
// : {nullptr, false}
// });
FilterIf(
/*FROM*/ sready.begin(),
sready.end(),
/*TO*/ std::inserter(w_broken, w_broken.begin()),
/*VIA*/ FLookupSocketWithEvent_LOCKED(&m_Global, SRT_EPOLL_ERR));
// If this set is empty, it won't roll even once, therefore output
// will be surely empty. This will be checked then same way as when
// reading from every socket resulted in error.
vector<CUDTSocket*> readReady;
readReady.reserve(aliveMembers.size());
for (vector<CUDTSocket*>::const_iterator sockiter = aliveMembers.begin(); sockiter != aliveMembers.end(); ++sockiter)
{
CUDTSocket* sock = *sockiter;
const CEPoll::fmap_t::const_iterator ready_iter = sready.find(sock->m_SocketID);
if (ready_iter != sready.end())
{
if (ready_iter->second & SRT_EPOLL_ERR)
continue; // broken already
if ((ready_iter->second & SRT_EPOLL_IN) == 0)
continue; // not ready for reading
readReady.push_back(*sockiter);
}
else
{
// No read-readiness reported by epoll, but probably missed or not yet handled
// as the receiver buffer is read-ready.
ScopedLock lg(sock->core().m_RcvBufferLock);
if (sock->core().m_pRcvBuffer && sock->core().m_pRcvBuffer->isRcvDataReady())
readReady.push_back(sock);
}
}
leaveCS(CUDT::uglobal().m_GlobControlLock);
return readReady;
}
void CUDTGroup::updateReadState(SRTSOCKET /* not sure if needed */, int32_t sequence)
{
bool ready = false;
ScopedLock lg(m_GroupLock);
int seqdiff = 0;
if (m_RcvBaseSeqNo == SRT_SEQNO_NONE)
{
// One socket reported readiness, while no reading operation
// has ever been done. Whatever the sequence number is, it will
// be taken as a good deal and reading will be accepted.
ready = true;
}
else if ((seqdiff = CSeqNo::seqcmp(sequence, m_RcvBaseSeqNo)) > 0)
{
// Case diff == 1: The very next. Surely read-ready.
// Case diff > 1:
// We have an ahead packet. There's one strict condition in which
// we may believe it needs to be delivered - when KANGAROO->HORSE
// transition is allowed. Stating that the time calculation is done
// exactly the same way on every link in the redundancy group, when
// it came to a situation that a packet from one link is ready for
// extraction while it has jumped over some packet, it has surely
// happened due to TLPKTDROP, and if it happened on at least one link,
// we surely don't have this packet ready on any other link.
// This might prove not exactly true, especially when at the moment
// when this happens another link may surprisinly receive this lacking
// packet, so the situation gets suddenly repaired after this function
// is called, the only result of it would be that it will really get
// the very next sequence, even though this function doesn't know it
// yet, but surely in both cases the situation is the same: the medium
// is ready for reading, no matter what packet will turn out to be
// returned when reading is done.
ready = true;
}
// When the sequence number is behind the current one,
// stating that the readines wasn't checked otherwise, the reading
// function will not retrieve anything ready to read just by this premise.
// Even though this packet would have to be eventually extracted (and discarded).
if (ready)
{
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_IN, true);
}
}
int32_t CUDTGroup::getRcvBaseSeqNo()
{
ScopedLock lg(m_GroupLock);
return m_RcvBaseSeqNo;
}
void CUDTGroup::updateWriteState()
{
ScopedLock lg(m_GroupLock);
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_OUT, true);
}
/// Validate iPktSeqno is in range
/// (iBaseSeqno - m_iSeqNoTH/2; iBaseSeqno + m_iSeqNoTH).
///
/// EXPECT_EQ(isValidSeqno(125, 124), true); // behind
/// EXPECT_EQ(isValidSeqno(125, 125), true); // behind
/// EXPECT_EQ(isValidSeqno(125, 126), true); // the next in order
///
/// EXPECT_EQ(isValidSeqno(0, 0x3FFFFFFF - 2), true); // ahead, but ok.
/// EXPECT_EQ(isValidSeqno(0, 0x3FFFFFFF - 1), false); // too far ahead.
/// EXPECT_EQ(isValidSeqno(0x3FFFFFFF + 2, 0x7FFFFFFF), false); // too far ahead.
/// EXPECT_EQ(isValidSeqno(0x3FFFFFFF + 3, 0x7FFFFFFF), true); // ahead, but ok.
/// EXPECT_EQ(isValidSeqno(0x3FFFFFFF, 0x1FFFFFFF + 2), false); // too far (behind)
/// EXPECT_EQ(isValidSeqno(0x3FFFFFFF, 0x1FFFFFFF + 3), true); // behind, but ok
/// EXPECT_EQ(isValidSeqno(0x70000000, 0x0FFFFFFF), true); // ahead, but ok
/// EXPECT_EQ(isValidSeqno(0x70000000, 0x30000000 - 2), false); // too far ahead.
/// EXPECT_EQ(isValidSeqno(0x70000000, 0x30000000 - 3), true); // ahead, but ok
/// EXPECT_EQ(isValidSeqno(0x0FFFFFFF, 0), true);
/// EXPECT_EQ(isValidSeqno(0x0FFFFFFF, 0x7FFFFFFF), true);
/// EXPECT_EQ(isValidSeqno(0x0FFFFFFF, 0x70000000), false);
/// EXPECT_EQ(isValidSeqno(0x0FFFFFFF, 0x70000001), false);
/// EXPECT_EQ(isValidSeqno(0x0FFFFFFF, 0x70000002), true); // behind by 536870910
/// EXPECT_EQ(isValidSeqno(0x0FFFFFFF, 0x70000003), true);
///
/// @return false if @a iPktSeqno is not inside the valid range; otherwise true.
static bool isValidSeqno(int32_t iBaseSeqno, int32_t iPktSeqno)
{
const int32_t iLenAhead = CSeqNo::seqlen(iBaseSeqno, iPktSeqno);
if (iLenAhead >= 0 && iLenAhead < CSeqNo::m_iSeqNoTH)
return true;
const int32_t iLenBehind = CSeqNo::seqlen(iPktSeqno, iBaseSeqno);
if (iLenBehind >= 0 && iLenBehind < CSeqNo::m_iSeqNoTH / 2)
return true;
return false;
}
int CUDTGroup::recv(char* buf, int len, SRT_MSGCTRL& w_mc)
{
// First, acquire GlobControlLock to make sure all member sockets still exist
enterCS(m_Global.m_GlobControlLock);
ScopedLock guard(m_GroupLock);
if (m_bClosing)
{
// The group could be set closing in the meantime, but if
// this is only about to be set by another thread, this thread
// must fist wait for being able to acquire this lock.
// The group will not be deleted now because it is added usage counter
// by this call, but will be released once it exits.
leaveCS(m_Global.m_GlobControlLock);
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
}
// Now, still under lock, check if all sockets still can be dispatched
send_CheckValidSockets();
leaveCS(m_Global.m_GlobControlLock);
if (m_bClosing)
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
// Later iteration over it might be less efficient than
// by vector, but we'll also often try to check a single id
// if it was ever seen broken, so that it's skipped.
set<CUDTSocket*> broken;
for (;;)
{
if (!m_bOpened || !m_bConnected)
{
LOGC(grlog.Error,
log << boolalpha << "grp/recv: $" << id() << ": ABANDONING: opened=" << m_bOpened
<< " connected=" << m_bConnected);
throw CUDTException(MJ_CONNECTION, MN_NOCONN, 0);
}
vector<CUDTSocket*> aliveMembers;
recv_CollectAliveAndBroken(aliveMembers, broken);
if (aliveMembers.empty())
{
LOGC(grlog.Error, log << "grp/recv: ALL LINKS BROKEN, ABANDONING.");
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_IN, false);
throw CUDTException(MJ_CONNECTION, MN_NOCONN, 0);
}
vector<CUDTSocket*> readySockets;
if (m_bSynRecving)
readySockets = recv_WaitForReadReady(aliveMembers, broken);
else
readySockets = aliveMembers;
if (m_bClosing)
{
HLOGC(grlog.Debug, log << "grp/recv: $" << id() << ": GROUP CLOSED, ABANDONING.");
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
}
// Find the first readable packet among all member sockets.
CUDTSocket* socketToRead = NULL;
CRcvBuffer::PacketInfo infoToRead = {-1, false, time_point()};
for (vector<CUDTSocket*>::const_iterator si = readySockets.begin(); si != readySockets.end(); ++si)
{
CUDTSocket* ps = *si;
ScopedLock lg(ps->core().m_RcvBufferLock);
if (m_RcvBaseSeqNo != SRT_SEQNO_NONE)
{
// Drop here to make sure the getFirstReadablePacketInfo() below return fresher packet.
int cnt = ps->core().rcvDropTooLateUpTo(CSeqNo::incseq(m_RcvBaseSeqNo));
if (cnt > 0)
{
HLOGC(grlog.Debug,
log << "grp/recv: $" << id() << ": @" << ps->m_SocketID << ": dropped " << cnt
<< " packets before reading: m_RcvBaseSeqNo=" << m_RcvBaseSeqNo);
}
}
const CRcvBuffer::PacketInfo info =
ps->core().m_pRcvBuffer->getFirstReadablePacketInfo(steady_clock::now());
if (info.seqno == SRT_SEQNO_NONE)
{
HLOGC(grlog.Debug, log << "grp/recv: $" << id() << ": @" << ps->m_SocketID << ": Nothing to read.");
continue;
}
// We need to qualify the sequence, just for a case.
if (m_RcvBaseSeqNo != SRT_SEQNO_NONE && !isValidSeqno(m_RcvBaseSeqNo, info.seqno))
{
LOGC(grlog.Error,
log << "grp/recv: $" << id() << ": @" << ps->m_SocketID << ": SEQUENCE DISCREPANCY: base=%"
<< m_RcvBaseSeqNo << " vs pkt=%" << info.seqno << ", setting ESECFAIL");
ps->core().m_bBroken = true;
broken.insert(ps);
continue;
}
if (socketToRead == NULL || CSeqNo::seqcmp(info.seqno, infoToRead.seqno) < 0)
{
socketToRead = ps;
infoToRead = info;
}
}
if (socketToRead == NULL)
{
if (m_bSynRecving)
{
HLOGC(grlog.Debug,
log << "grp/recv: $" << id() << ": No links reported any fresher packet, re-polling.");
continue;
}
else
{
HLOGC(grlog.Debug,
log << "grp/recv: $" << id() << ": No links reported any fresher packet, clearing readiness.");
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_IN, false);
throw CUDTException(MJ_AGAIN, MN_RDAVAIL, 0);
}
}
else
{
HLOGC(grlog.Debug,
log << "grp/recv: $" << id() << ": Found first readable packet from @" << socketToRead->m_SocketID
<< ": seq=" << infoToRead.seqno << " gap=" << infoToRead.seq_gap
<< " time=" << FormatTime(infoToRead.tsbpd_time));
}
const int res = socketToRead->core().receiveMessage((buf), len, (w_mc), CUDTUnited::ERH_RETURN);
HLOGC(grlog.Debug,
log << "grp/recv: $" << id() << ": @" << socketToRead->m_SocketID << ": Extracted data with %"
<< w_mc.pktseq << " #" << w_mc.msgno << ": " << (res <= 0 ? "(NOTHING)" : BufferStamp(buf, res)));
if (res == 0)
{
LOGC(grlog.Warn,
log << "grp/recv: $" << id() << ": @" << socketToRead->m_SocketID << ": Retrying next socket...");
// This socket will not be socketToRead in the next turn because receiveMessage() return 0 here.
continue;
}
if (res == SRT_ERROR)
{
LOGC(grlog.Warn,
log << "grp/recv: $" << id() << ": @" << socketToRead->m_SocketID << ": " << srt_getlasterror_str()
<< ". Retrying next socket...");
broken.insert(socketToRead);
continue;
}
fillGroupData((w_mc), w_mc);
HLOGC(grlog.Debug,
log << "grp/recv: $" << id() << ": Update m_RcvBaseSeqNo: %" << m_RcvBaseSeqNo << " -> %" << w_mc.pktseq);
m_RcvBaseSeqNo = w_mc.pktseq;
// Update stats as per delivery
m_stats.recv.count(res);
updateAvgPayloadSize(res);
bool canReadFurther = false;
for (vector<CUDTSocket*>::const_iterator si = aliveMembers.begin(); si != aliveMembers.end(); ++si)
{
CUDTSocket* ps = *si;
ScopedLock lg(ps->core().m_RcvBufferLock);
if (m_RcvBaseSeqNo != SRT_SEQNO_NONE)
{
const int cnt = ps->core().rcvDropTooLateUpTo(CSeqNo::incseq(m_RcvBaseSeqNo));
if (cnt > 0)
{
HLOGC(grlog.Debug,
log << "grp/recv: $" << id() << ": @" << ps->m_SocketID << ": dropped " << cnt
<< " packets after reading: m_RcvBaseSeqNo=" << m_RcvBaseSeqNo);
}
}
if (!ps->core().isRcvBufferReadyNoLock())
m_Global.m_EPoll.update_events(ps->m_SocketID, ps->core().m_sPollID, SRT_EPOLL_IN, false);
else
canReadFurther = true;
}
if (!canReadFurther)
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_IN, false);
return res;
}
LOGC(grlog.Error, log << "grp/recv: UNEXPECTED RUN PATH, ABANDONING.");
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_IN, false);
throw CUDTException(MJ_AGAIN, MN_RDAVAIL, 0);
}
const char* CUDTGroup::StateStr(CUDTGroup::GroupState st)
{
static const char* const states[] = {"PENDING", "IDLE", "RUNNING", "BROKEN"};
static const size_t size = Size(states);
static const char* const unknown = "UNKNOWN";
if (size_t(st) < size)
return states[st];
return unknown;
}
void CUDTGroup::synchronizeDrift(const srt::CUDT* srcMember)
{
SRT_ASSERT(srcMember != NULL);
ScopedLock glock(m_GroupLock);
if (m_Group.size() <= 1)
{
HLOGC(grlog.Debug, log << "GROUP: synch uDRIFT NOT DONE, no other links");
return;
}
steady_clock::time_point timebase;
steady_clock::duration udrift(0);
bool wrap_period = false;
srcMember->m_pRcvBuffer->getInternalTimeBase((timebase), (wrap_period), (udrift));
HLOGC(grlog.Debug,
log << "GROUP: synch uDRIFT=" << FormatDuration(udrift) << " TB=" << FormatTime(timebase) << "("
<< (wrap_period ? "" : "NO ") << "wrap period)");
// Now that we have the minimum timebase and drift calculated, apply this to every link,
// INCLUDING THE REPORTER.
for (gli_t gi = m_Group.begin(); gi != m_Group.end(); ++gi)
{
// Skip non-connected; these will be synchronized when ready
if (gi->laststatus != SRTS_CONNECTED)
continue;
CUDT& member = gi->ps->core();
if (srcMember == &member)
continue;
member.m_pRcvBuffer->applyGroupDrift(timebase, wrap_period, udrift);
}
}
void CUDTGroup::bstatsSocket(CBytePerfMon* perf, bool clear)
{
if (!m_bConnected)
throw CUDTException(MJ_CONNECTION, MN_NOCONN, 0);
if (m_bClosing)
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
const steady_clock::time_point currtime = steady_clock::now();
memset(perf, 0, sizeof *perf);
ScopedLock gg(m_GroupLock);
perf->msTimeStamp = count_milliseconds(currtime - m_tsStartTime);
perf->pktSentUnique = m_stats.sent.trace.count();
perf->pktRecvUnique = m_stats.recv.trace.count();
perf->pktRcvDrop = m_stats.recvDrop.trace.count();
perf->byteSentUnique = m_stats.sent.trace.bytesWithHdr();
perf->byteRecvUnique = m_stats.recv.trace.bytesWithHdr();
perf->byteRcvDrop = m_stats.recvDrop.trace.bytesWithHdr();
perf->pktSentUniqueTotal = m_stats.sent.total.count();
perf->pktRecvUniqueTotal = m_stats.recv.total.count();
perf->pktRcvDropTotal = m_stats.recvDrop.total.count();
perf->byteSentUniqueTotal = m_stats.sent.total.bytesWithHdr();
perf->byteRecvUniqueTotal = m_stats.recv.total.bytesWithHdr();
perf->byteRcvDropTotal = m_stats.recvDrop.total.bytesWithHdr();
const double interval = static_cast<double>(count_microseconds(currtime - m_stats.tsLastSampleTime));
perf->mbpsSendRate = double(perf->byteSent) * 8.0 / interval;
perf->mbpsRecvRate = double(perf->byteRecv) * 8.0 / interval;
if (clear)
{
m_stats.reset();
}
}
/// @brief Compares group members by their weight (higher weight comes first).
struct FCompareByWeight
{
typedef CUDTGroup::gli_t gli_t;
/// @returns true if the first argument is less than (i.e. is ordered before) the second.
bool operator()(const gli_t preceding, const gli_t succeeding)
{
return preceding->weight > succeeding->weight;
}
};
// [[using maybe_locked(this->m_GroupLock)]]
BackupMemberState CUDTGroup::sendBackup_QualifyIfStandBy(const gli_t d)
{
if (!d->ps)
return BKUPST_BROKEN;
const SRT_SOCKSTATUS st = d->ps->getStatus();
// If the socket is already broken, move it to broken.
if (int(st) >= int(SRTS_BROKEN))
{
HLOGC(gslog.Debug,
log << "CUDTGroup::send.$" << id() << ": @" << d->id << " became " << SockStatusStr(st)
<< ", WILL BE CLOSED.");
return BKUPST_BROKEN;
}
if (st != SRTS_CONNECTED)
{
HLOGC(gslog.Debug, log << "CUDTGroup::send. @" << d->id << " is still " << SockStatusStr(st) << ", skipping.");
return BKUPST_PENDING;
}
return BKUPST_STANDBY;
}
// [[using maybe_locked(this->m_GroupLock)]]
bool CUDTGroup::send_CheckIdle(const gli_t d, vector<SRTSOCKET>& w_wipeme, vector<SRTSOCKET>& w_pendingSockets)
{
SRT_SOCKSTATUS st = SRTS_NONEXIST;
if (d->ps)
st = d->ps->getStatus();
// If the socket is already broken, move it to broken.
if (int(st) >= int(SRTS_BROKEN))
{
HLOGC(gslog.Debug,
log << "CUDTGroup::send.$" << id() << ": @" << d->id << " became " << SockStatusStr(st)
<< ", WILL BE CLOSED.");
w_wipeme.push_back(d->id);
return false;
}
if (st != SRTS_CONNECTED)
{
HLOGC(gslog.Debug, log << "CUDTGroup::send. @" << d->id << " is still " << SockStatusStr(st) << ", skipping.");
w_pendingSockets.push_back(d->id);
return false;
}
return true;
}
#if SRT_DEBUG_BONDING_STATES
class StabilityTracer
{
public:
StabilityTracer()
{
}
~StabilityTracer()
{
srt::sync::ScopedLock lck(m_mtx);
m_fout.close();
}
void trace(const CUDT& u, const srt::sync::steady_clock::time_point& currtime, uint32_t activation_period_us,
int64_t stability_tmo_us, const std::string& state, uint16_t weight)
{
srt::sync::ScopedLock lck(m_mtx);
create_file();
m_fout << srt::sync::FormatTime(currtime) << ",";
m_fout << u.id() << ",";
m_fout << weight << ",";
m_fout << u.peerLatency_us() << ",";
m_fout << u.SRTT() << ",";
m_fout << u.RTTVar() << ",";
m_fout << stability_tmo_us << ",";
m_fout << count_microseconds(currtime - u.lastRspTime()) << ",";
m_fout << state << ",";
m_fout << (srt::sync::is_zero(u.freshActivationStart()) ? -1 : (count_microseconds(currtime - u.freshActivationStart()))) << ",";
m_fout << activation_period_us << "\n";
m_fout.flush();
}
private:
void print_header()
{
//srt::sync::ScopedLock lck(m_mtx);
m_fout << "Timepoint,SocketID,weight,usLatency,usRTT,usRTTVar,usStabilityTimeout,usSinceLastResp,State,usSinceActivation,usActivationPeriod\n";
}
void create_file()
{
if (m_fout.is_open())
return;
std::string str_tnow = srt::sync::FormatTimeSys(srt::sync::steady_clock::now());
str_tnow.resize(str_tnow.size() - 7); // remove trailing ' [SYST]' part
while (str_tnow.find(':') != std::string::npos) {
str_tnow.replace(str_tnow.find(':'), 1, 1, '_');
}
const std::string fname = "stability_trace_" + str_tnow + ".csv";
m_fout.open(fname, std::ofstream::out);
if (!m_fout)
std::cerr << "IPE: Failed to open " << fname << "!!!\n";
print_header();
}
private:
srt::sync::Mutex m_mtx;
std::ofstream m_fout;
};
StabilityTracer s_stab_trace;
#endif
void CUDTGroup::sendBackup_QualifyMemberStates(SendBackupCtx& w_sendBackupCtx, const steady_clock::time_point& currtime)
{
// First, check status of every link - no matter if idle or active.
for (gli_t d = m_Group.begin(); d != m_Group.end(); ++d)
{
if (d->sndstate != SRT_GST_BROKEN)
{
// Check the socket state prematurely in order not to uselessly
// send over a socket that is broken.
CUDT* const pu = (d->ps)
? &d->ps->core()
: NULL;
if (!pu || pu->m_bBroken)
{
HLOGC(gslog.Debug, log << "grp/sendBackup: socket @" << d->id << " detected +Broken - transit to BROKEN");
d->sndstate = SRT_GST_BROKEN;
d->rcvstate = SRT_GST_BROKEN;
}
}
// Check socket sndstate before sending
if (d->sndstate == SRT_GST_BROKEN)
{
HLOGC(gslog.Debug,
log << "grp/sendBackup: socket in BROKEN state: @" << d->id
<< ", sockstatus=" << SockStatusStr(d->ps ? d->ps->getStatus() : SRTS_NONEXIST));
sendBackup_AssignBackupState(d->ps->core(), BKUPST_BROKEN, currtime);
w_sendBackupCtx.recordMemberState(&(*d), BKUPST_BROKEN);
#if SRT_DEBUG_BONDING_STATES
s_stab_trace.trace(d->ps->core(), currtime, 0, 0, stateToStr(BKUPST_BROKEN), d->weight);
#endif
continue;
}
if (d->sndstate == SRT_GST_IDLE)
{
const BackupMemberState idle_state = sendBackup_QualifyIfStandBy(d);
sendBackup_AssignBackupState(d->ps->core(), idle_state, currtime);
w_sendBackupCtx.recordMemberState(&(*d), idle_state);
if (idle_state == BKUPST_STANDBY)
{
// TODO: Check if this is some abandoned logic.
sendBackup_CheckIdleTime(d);
}
#if SRT_DEBUG_BONDING_STATES
s_stab_trace.trace(d->ps->core(), currtime, 0, 0, stateToStr(idle_state), d->weight);
#endif
continue;
}
if (d->sndstate == SRT_GST_RUNNING)
{
const BackupMemberState active_state = sendBackup_QualifyActiveState(d, currtime);
sendBackup_AssignBackupState(d->ps->core(), active_state, currtime);
w_sendBackupCtx.recordMemberState(&(*d), active_state);
#if SRT_DEBUG_BONDING_STATES
s_stab_trace.trace(d->ps->core(), currtime, 0, 0, stateToStr(active_state), d->weight);
#endif
continue;
}
HLOGC(gslog.Debug,
log << "grp/sendBackup: socket @" << d->id << " not ready, state: " << StateStr(d->sndstate) << "("
<< int(d->sndstate) << ") - NOT sending, SET AS PENDING");
// Otherwise connection pending
sendBackup_AssignBackupState(d->ps->core(), BKUPST_PENDING, currtime);
w_sendBackupCtx.recordMemberState(&(*d), BKUPST_PENDING);
#if SRT_DEBUG_BONDING_STATES
s_stab_trace.trace(d->ps->core(), currtime, 0, 0, stateToStr(BKUPST_PENDING), d->weight);
#endif
}
}
void CUDTGroup::sendBackup_AssignBackupState(CUDT& sock, BackupMemberState state, const steady_clock::time_point& currtime)
{
switch (state)
{
case BKUPST_PENDING:
case BKUPST_STANDBY:
case BKUPST_BROKEN:
sock.m_tsFreshActivation = steady_clock::time_point();
sock.m_tsUnstableSince = steady_clock::time_point();
sock.m_tsWarySince = steady_clock::time_point();
break;
case BKUPST_ACTIVE_FRESH:
if (is_zero(sock.freshActivationStart()))
{
sock.m_tsFreshActivation = currtime;
}
sock.m_tsUnstableSince = steady_clock::time_point();
sock.m_tsWarySince = steady_clock::time_point();;
break;
case BKUPST_ACTIVE_STABLE:
sock.m_tsFreshActivation = steady_clock::time_point();
sock.m_tsUnstableSince = steady_clock::time_point();
sock.m_tsWarySince = steady_clock::time_point();
break;
case BKUPST_ACTIVE_UNSTABLE:
if (is_zero(sock.m_tsUnstableSince))
{
sock.m_tsUnstableSince = currtime;
}
sock.m_tsFreshActivation = steady_clock::time_point();
sock.m_tsWarySince = steady_clock::time_point();
break;
case BKUPST_ACTIVE_UNSTABLE_WARY:
if (is_zero(sock.m_tsWarySince))
{
sock.m_tsWarySince = currtime;
}
break;
default:
break;
}
}
// [[using locked(this->m_GroupLock)]]
void CUDTGroup::sendBackup_CheckIdleTime(gli_t w_d)
{
// Check if it was fresh set as idle, we had to wait until its sender
// buffer gets empty so that we can make sure that KEEPALIVE will be the
// really last sent for longer time.
CUDT& u = w_d->ps->core();
if (is_zero(u.m_tsFreshActivation)) // TODO: Check if this condition is ever false
return;
CSndBuffer* b = u.m_pSndBuffer;
if (b && b->getCurrBufSize() == 0)
{
HLOGC(gslog.Debug,
log << "grp/sendBackup: FRESH IDLE LINK reached empty buffer - setting permanent and KEEPALIVE");
u.m_tsFreshActivation = steady_clock::time_point();
// Send first immediate keepalive. The link is to be turn to IDLE
// now so nothing will be sent to it over time and it will start
// getting KEEPALIVES since now. Send the first one now to increase
// probability that the link will be recognized as IDLE on the
// reception side ASAP.
int32_t arg = 1;
w_d->ps->core().sendCtrl(UMSG_KEEPALIVE, &arg);
}
}
// [[using locked(this->m_GroupLock)]]
CUDTGroup::BackupMemberState CUDTGroup::sendBackup_QualifyActiveState(const gli_t d, const time_point currtime)
{
const CUDT& u = d->ps->core();
const uint32_t latency_us = u.peerLatency_us();
const int32_t min_stability_us = m_uOPT_MinStabilityTimeout_us;
const int64_t initial_stabtout_us = max<int64_t>(min_stability_us, latency_us);
const int64_t probing_period_us = initial_stabtout_us + 5 * CUDT::COMM_SYN_INTERVAL_US;
// RTT and RTTVar values are still being refined during the probing period,
// therefore the dymanic timeout should not be used during the probing period.
const bool is_activation_phase = !is_zero(u.freshActivationStart())
&& (count_microseconds(currtime - u.freshActivationStart()) <= probing_period_us);
// Initial stability timeout is used only in activation phase.
// Otherwise runtime stability is used, including the WARY state.
const int64_t stability_tout_us = is_activation_phase
? initial_stabtout_us // activation phase
: min<int64_t>(max<int64_t>(min_stability_us, 2 * u.SRTT() + 4 * u.RTTVar()), latency_us);
const steady_clock::time_point last_rsp = max(u.freshActivationStart(), u.lastRspTime());
const steady_clock::duration td_response = currtime - last_rsp;
// No response for a long time
if (count_microseconds(td_response) > stability_tout_us)
{
return BKUPST_ACTIVE_UNSTABLE;
}
enterCS(u.m_StatsLock);
const int64_t drop_total = u.m_stats.sndr.dropped.total.count();
leaveCS(u.m_StatsLock);
const bool have_new_drops = d->pktSndDropTotal != drop_total;
if (have_new_drops)
{
d->pktSndDropTotal = drop_total;
if (!is_activation_phase)
return BKUPST_ACTIVE_UNSTABLE;
}
// Responsive: either stable, wary or still fresh activated.
if (is_activation_phase)
return BKUPST_ACTIVE_FRESH;
const bool is_wary = !is_zero(u.m_tsWarySince);
const bool is_wary_probing = is_wary
&& (count_microseconds(currtime - u.m_tsWarySince) <= 4 * u.peerLatency_us());
const bool is_unstable = !is_zero(u.m_tsUnstableSince);
// If unstable and not in wary, become wary.
if (is_unstable && !is_wary)
return BKUPST_ACTIVE_UNSTABLE_WARY;
// Still probing for stability.
if (is_wary_probing)
return BKUPST_ACTIVE_UNSTABLE_WARY;
if (is_wary)
{
LOGC(gslog.Debug,
log << "grp/sendBackup: @" << u.id() << " wary->stable after " << count_milliseconds(currtime - u.m_tsWarySince) << " ms");
}
return BKUPST_ACTIVE_STABLE;
}
// [[using locked(this->m_GroupLock)]]
bool CUDTGroup::sendBackup_CheckSendStatus(const steady_clock::time_point& currtime SRT_ATR_UNUSED,
const int send_status,
const int32_t lastseq,
const int32_t pktseq,
CUDT& w_u,
int32_t& w_curseq,
int& w_final_stat)
{
if (send_status == -1)
return false; // Sending failed.
bool send_succeeded = false;
if (w_curseq == SRT_SEQNO_NONE)
{
w_curseq = pktseq;
}
else if (w_curseq != lastseq)
{
// We believe that all active links use the same seq.
// But we can do some sanity check.
LOGC(gslog.Error,
log << "grp/sendBackup: @" << w_u.m_SocketID << ": IPE: another running link seq discrepancy: %"
<< lastseq << " vs. previous %" << w_curseq << " - fixing");
// Override must be done with a sequence number greater by one.
// Example:
//
// Link 1 before sending: curr=1114, next=1115
// After sending it reports pktseq=1115
//
// Link 2 before sending: curr=1110, next=1111 (->lastseq before sending)
// THIS CHECK done after sending:
// -- w_curseq(1115) != lastseq(1111)
//
// NOW: Link 1 after sending is:
// curr=1115, next=1116
//
// The value of w_curseq here = 1115, while overrideSndSeqNo
// calls setInitialSndSeq(seq), which sets:
// - curr = seq - 1
// - next = seq
//
// So, in order to set curr=1115, next=1116
// this must set to 1115+1.
w_u.overrideSndSeqNo(CSeqNo::incseq(w_curseq));
}
// State it as succeeded, though. We don't know if the link
// is broken until we get the connection broken confirmation,
// and the instability state may wear off next time.
send_succeeded = true;
w_final_stat = send_status;
return send_succeeded;
}
// [[using locked(this->m_GroupLock)]]
void CUDTGroup::sendBackup_Buffering(const char* buf, const int len, int32_t& w_curseq, SRT_MSGCTRL& w_mc)
{
// This is required to rewrite into currentSchedSequence() property
// as this value will be used as ISN when a new link is connected.
int32_t oldest_buffer_seq = SRT_SEQNO_NONE;
if (w_curseq != SRT_SEQNO_NONE)
{
HLOGC(gslog.Debug, log << "grp/sendBackup: successfully sent over running link, ADDING TO BUFFER.");
// Note: the sequence number that was used to send this packet should be
// recorded here.
oldest_buffer_seq = addMessageToBuffer(buf, len, (w_mc));
}
else
{
// We have to predict, which sequence number would have
// to be placed on the packet about to be sent now. To
// maintain consistency:
// 1. If there are any packets in the sender buffer,
// get the sequence of the last packet, increase it.
// This must be done even if this contradicts the ISN
// of all idle links because otherwise packets will get
// discrepancy.
if (!m_SenderBuffer.empty())
{
BufferedMessage& m = m_SenderBuffer.back();
w_curseq = CSeqNo::incseq(m.mc.pktseq);
// Set also this sequence to the current w_mc
w_mc.pktseq = w_curseq;
// XXX may need tighter revision when message mode is allowed
w_mc.msgno = ++MsgNo(m.mc.msgno);
oldest_buffer_seq = addMessageToBuffer(buf, len, (w_mc));
}
// Note that if buffer is empty and w_curseq is (still) SRT_SEQNO_NONE,
// it will have to try to send first in order to extract the data.
// Note that if w_curseq is still SRT_SEQNO_NONE at this point, it means
// that we have the case of the very first packet sending.
// Otherwise there would be something in the buffer already.
}
if (oldest_buffer_seq != SRT_SEQNO_NONE)
m_iLastSchedSeqNo = oldest_buffer_seq;
}
size_t CUDTGroup::sendBackup_TryActivateStandbyIfNeeded(
const char* buf,
const int len,
bool& w_none_succeeded,
SRT_MSGCTRL& w_mc,
int32_t& w_curseq,
int32_t& w_final_stat,
SendBackupCtx& w_sendBackupCtx,
CUDTException& w_cx,
const steady_clock::time_point& currtime)
{
const unsigned num_standby = w_sendBackupCtx.countMembersByState(BKUPST_STANDBY);
if (num_standby == 0)
{
return 0;
}
const unsigned num_stable = w_sendBackupCtx.countMembersByState(BKUPST_ACTIVE_STABLE);
const unsigned num_fresh = w_sendBackupCtx.countMembersByState(BKUPST_ACTIVE_FRESH);
if (num_stable + num_fresh == 0)
{
LOGC(gslog.Warn,
log << "grp/sendBackup: trying to activate a stand-by link (" << num_standby << " available). "
<< "Reason: no stable links"
);
}
else if (w_sendBackupCtx.maxActiveWeight() < w_sendBackupCtx.maxStandbyWeight())
{
LOGC(gslog.Warn,
log << "grp/sendBackup: trying to activate a stand-by link (" << num_standby << " available). "
<< "Reason: max active weight " << w_sendBackupCtx.maxActiveWeight()
<< ", max stand by weight " << w_sendBackupCtx.maxStandbyWeight()
);
}
else
{
/*LOGC(gslog.Warn,
log << "grp/sendBackup: no need to activate (" << num_standby << " available). "
<< "Max active weight " << w_sendBackupCtx.maxActiveWeight()
<< ", max stand by weight " << w_sendBackupCtx.maxStandbyWeight()
);*/
return 0;
}
int stat = -1;
size_t num_activated = 0;
w_sendBackupCtx.sortByWeightAndState();
typedef vector<BackupMemberStateEntry>::const_iterator const_iter_t;
for (const_iter_t member = w_sendBackupCtx.memberStates().begin(); member != w_sendBackupCtx.memberStates().end(); ++member)
{
if (member->state != BKUPST_STANDBY)
continue;
int erc = 0;
SocketData* d = member->pSocketData;
// Now send and check the status
// The link could have got broken
try
{
CUDT& cudt = d->ps->core();
// Take source rate estimation from an active member (needed for the input rate estimation mode).
cudt.setRateEstimator(w_sendBackupCtx.getRateEstimate());
// TODO: At this point all packets that could be sent
// are located in m_SenderBuffer. So maybe just use sendBackupRexmit()?
if (w_curseq == SRT_SEQNO_NONE)
{
// This marks the fact that the given here packet
// could not be sent over any link. This includes the
// situation of sending the very first packet after connection.
HLOGC(gslog.Debug,
log << "grp/sendBackup: ... trying @" << d->id << " - sending the VERY FIRST message");
stat = cudt.sendmsg2(buf, len, (w_mc));
if (stat != -1)
{
// This will be no longer used, but let it stay here.
// It's because if this is successful, no other links
// will be tried.
w_curseq = w_mc.pktseq;
addMessageToBuffer(buf, len, (w_mc));
}
}
else
{
HLOGC(gslog.Debug,
log << "grp/sendBackup: ... trying @" << d->id << " - resending " << m_SenderBuffer.size()
<< " collected messages...");
// Note: this will set the currently required packet
// because it has been just freshly added to the sender buffer
stat = sendBackupRexmit(cudt, (w_mc));
}
++num_activated;
}
catch (CUDTException& e)
{
// This will be propagated from internal sendmsg2 call,
// but that's ok - we want this sending interrupted even in half.
w_cx = e;
stat = -1;
erc = e.getErrorCode();
}
d->sndresult = stat;
d->laststatus = d->ps->getStatus();
if (stat != -1)
{
d->sndstate = SRT_GST_RUNNING;
sendBackup_AssignBackupState(d->ps->core(), BKUPST_ACTIVE_FRESH, currtime);
w_sendBackupCtx.updateMemberState(d, BKUPST_ACTIVE_FRESH);
// Note: this will override the sequence number
// for all next iterations in this loop.
w_none_succeeded = false;
w_final_stat = stat;
LOGC(gslog.Warn,
log << "@" << d->id << " FRESH-ACTIVATED");
// We've activated the link, so that's enough.
break;
}
// Failure - move to broken those that could not be activated
bool isblocked SRT_ATR_UNUSED = true;
if (erc != SRT_EASYNCSND)
{
isblocked = false;
sendBackup_AssignBackupState(d->ps->core(), BKUPST_BROKEN, currtime);
w_sendBackupCtx.updateMemberState(d, BKUPST_BROKEN);
}
// If we found a blocked link, leave it alone, however
// still try to send something over another link
LOGC(gslog.Warn,
log << "@" << d->id << " FAILED (" << (isblocked ? "blocked" : "ERROR")
<< "), trying to activate another link.");
}
return num_activated;
}
// [[using locked(this->m_GroupLock)]]
void CUDTGroup::sendBackup_CheckPendingSockets(SendBackupCtx& w_sendBackupCtx, const steady_clock::time_point& currtime)
{
if (w_sendBackupCtx.countMembersByState(BKUPST_PENDING) == 0)
return;
HLOGC(gslog.Debug, log << "grp/send*: checking pending sockets.");
// These sockets if they are in pending state, should be added to m_SndEID
// at the connecting stage.
CEPoll::fmap_t sready;
if (m_Global.m_EPoll.empty(*m_SndEpolld))
{
// Sanity check - weird pending reported.
LOGC(gslog.Error, log << "grp/send*: IPE: reported pending sockets, but EID is empty - wiping pending!");
return;
}
{
InvertedLock ug(m_GroupLock);
m_Global.m_EPoll.swait(
*m_SndEpolld, sready, 0, false /*report by retval*/); // Just check if anything has happened
}
if (m_bClosing)
{
HLOGC(gslog.Debug, log << "grp/send...: GROUP CLOSED, ABANDONING");
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
}
// Some sockets could have been closed in the meantime.
if (m_Global.m_EPoll.empty(*m_SndEpolld))
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
HLOGC(gslog.Debug, log << "grp/send*: RDY: " << DisplayEpollResults(sready));
typedef vector<BackupMemberStateEntry>::const_iterator const_iter_t;
for (const_iter_t member = w_sendBackupCtx.memberStates().begin(); member != w_sendBackupCtx.memberStates().end(); ++member)
{
if (member->state != BKUPST_PENDING)
continue;
const SRTSOCKET sockid = member->pSocketData->id;
if (!CEPoll::isready(sready, sockid, SRT_EPOLL_ERR))
continue;
HLOGC(gslog.Debug, log << "grp/send*: Socket @" << sockid << " reported FAILURE - qualifying as broken.");
w_sendBackupCtx.updateMemberState(member->pSocketData, BKUPST_BROKEN);
if (member->pSocketData->ps)
sendBackup_AssignBackupState(member->pSocketData->ps->core(), BKUPST_BROKEN, currtime);
const int no_events = 0;
m_Global.m_EPoll.update_usock(m_SndEID, sockid, &no_events);
}
// After that, all sockets that have been reported
// as ready to write should be removed from EID. This
// will also remove those sockets that have been added
// as redundant links at the connecting stage and became
// writable (connected) before this function had a chance
// to check them.
m_Global.m_EPoll.clear_ready_usocks(*m_SndEpolld, SRT_EPOLL_OUT);
}
// [[using locked(this->m_GroupLock)]]
void CUDTGroup::sendBackup_CheckUnstableSockets(SendBackupCtx& w_sendBackupCtx, const steady_clock::time_point& currtime)
{
const unsigned num_stable = w_sendBackupCtx.countMembersByState(BKUPST_ACTIVE_STABLE);
if (num_stable == 0)
return;
const unsigned num_unstable = w_sendBackupCtx.countMembersByState(BKUPST_ACTIVE_UNSTABLE);
const unsigned num_wary = w_sendBackupCtx.countMembersByState(BKUPST_ACTIVE_UNSTABLE_WARY);
if (num_unstable + num_wary == 0)
return;
HLOGC(gslog.Debug, log << "grp/send*: checking unstable sockets.");
typedef vector<BackupMemberStateEntry>::const_iterator const_iter_t;
for (const_iter_t member = w_sendBackupCtx.memberStates().begin(); member != w_sendBackupCtx.memberStates().end(); ++member)
{
if (member->state != BKUPST_ACTIVE_UNSTABLE && member->state != BKUPST_ACTIVE_UNSTABLE_WARY)
continue;
CUDT& sock = member->pSocketData->ps->core();
if (is_zero(sock.m_tsUnstableSince))
{
LOGC(gslog.Error, log << "grp/send* IPE: Socket @" << member->socketID
<< " is qualified as unstable, but does not have the 'unstable since' timestamp. Still marking for closure.");
}
const int unstable_for_ms = (int)count_milliseconds(currtime - sock.m_tsUnstableSince);
if (unstable_for_ms < sock.peerIdleTimeout_ms())
continue;
// Requesting this socket to be broken with the next CUDT::checkExpTimer() call.
sock.breakAsUnstable();
LOGC(gslog.Warn, log << "grp/send*: Socket @" << member->socketID << " is unstable for " << unstable_for_ms
<< "ms - requesting breakage.");
//w_sendBackupCtx.updateMemberState(member->pSocketData, BKUPST_BROKEN);
//if (member->pSocketData->ps)
// sendBackup_AssignBackupState(member->pSocketData->ps->core(), BKUPST_BROKEN, currtime);
}
}
// [[using locked(this->m_GroupLock)]]
void CUDTGroup::send_CloseBrokenSockets(vector<SRTSOCKET>& w_wipeme)
{
if (!w_wipeme.empty())
{
InvertedLock ug(m_GroupLock);
// With unlocked GroupLock, we can now lock GlobControlLock.
// This is needed prevent any of them be deleted from the container
// at the same time.
ScopedLock globlock(CUDT::uglobal().m_GlobControlLock);
for (vector<SRTSOCKET>::iterator p = w_wipeme.begin(); p != w_wipeme.end(); ++p)
{
CUDTSocket* s = CUDT::uglobal().locateSocket_LOCKED(*p);
// If the socket has been just moved to ClosedSockets, it means that
// the object still exists, but it will be no longer findable.
if (!s)
continue;
HLOGC(gslog.Debug,
log << "grp/send...: BROKEN SOCKET @" << (*p) << " - CLOSING, to be removed from group.");
// As per sending, make it also broken so that scheduled
// packets will be also abandoned.
s->setClosed();
}
}
HLOGC(gslog.Debug, log << "grp/send...: - wiped " << w_wipeme.size() << " broken sockets");
// We'll need you again.
w_wipeme.clear();
}
// [[using locked(this->m_GroupLock)]]
void CUDTGroup::sendBackup_CloseBrokenSockets(SendBackupCtx& w_sendBackupCtx)
{
if (w_sendBackupCtx.countMembersByState(BKUPST_BROKEN) == 0)
return;
InvertedLock ug(m_GroupLock);
// With unlocked GroupLock, we can now lock GlobControlLock.
// This is needed prevent any of them be deleted from the container
// at the same time.
ScopedLock globlock(CUDT::uglobal().m_GlobControlLock);
typedef vector<BackupMemberStateEntry>::const_iterator const_iter_t;
for (const_iter_t member = w_sendBackupCtx.memberStates().begin(); member != w_sendBackupCtx.memberStates().end(); ++member)
{
if (member->state != BKUPST_BROKEN)
continue;
// m_GroupLock is unlocked, therefore member->pSocketData can't be used.
const SRTSOCKET sockid = member->socketID;
CUDTSocket* s = CUDT::uglobal().locateSocket_LOCKED(sockid);
// If the socket has been just moved to ClosedSockets, it means that
// the object still exists, but it will be no longer findable.
if (!s)
continue;
LOGC(gslog.Debug,
log << "grp/send...: BROKEN SOCKET @" << sockid << " - CLOSING, to be removed from group.");
// As per sending, make it also broken so that scheduled
// packets will be also abandoned.
s->setBrokenClosed();
}
// TODO: all broken members are to be removed from the context now???
}
// [[using locked(this->m_GroupLock)]]
void CUDTGroup::sendBackup_RetryWaitBlocked(SendBackupCtx& w_sendBackupCtx,
int& w_final_stat,
bool& w_none_succeeded,
SRT_MSGCTRL& w_mc,
CUDTException& w_cx)
{
// In contradiction to broadcast sending, backup sending must check
// the blocking state in total first. We need this information through
// epoll because we didn't use all sockets to send the data hence the
// blocked socket information would not be complete.
// Don't do this check if sending has succeeded over at least one
// stable link. This procedure is to wait for at least one write-ready
// link.
//
// If sending succeeded also over at least one unstable link (you only have
// unstable links and none other or others just got broken), continue sending
// anyway.
// This procedure is for a case when the packet could not be sent
// over any link (hence "none succeeded"), but there are some unstable
// links and no parallel links. We need to WAIT for any of the links
// to become available for sending.
// Note: A link is added in unstableLinks if sending has failed with SRT_ESYNCSND.
const unsigned num_unstable = w_sendBackupCtx.countMembersByState(BKUPST_ACTIVE_UNSTABLE);
const unsigned num_wary = w_sendBackupCtx.countMembersByState(BKUPST_ACTIVE_UNSTABLE_WARY);
if ((num_unstable + num_wary == 0) || !w_none_succeeded)
return;
HLOGC(gslog.Debug, log << "grp/sendBackup: no successfull sending: "
<< (num_unstable + num_wary) << " unstable links - waiting to retry sending...");
// Note: GroupLock is set already, skip locks and checks
getGroupData_LOCKED((w_mc.grpdata), (&w_mc.grpdata_size));
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_OUT, false);
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_ERR, true);
if (m_Global.m_EPoll.empty(*m_SndEpolld))
{
// wipeme wiped, pending sockets checked, it can only mean that
// all sockets are broken.
HLOGC(gslog.Debug, log << "grp/sendBackup: epolld empty - all sockets broken?");
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
}
if (!m_bSynSending)
{
HLOGC(gslog.Debug, log << "grp/sendBackup: non-blocking mode - exit with no-write-ready");
throw CUDTException(MJ_AGAIN, MN_WRAVAIL, 0);
}
// Here is the situation that the only links left here are:
// - those that failed to send (already closed and wiped out)
// - those that got blockade on sending
// At least, there was so far no socket through which we could
// successfully send anything.
// As a last resort in this situation, try to wait for any links
// remaining in the group to become ready to write.
CEPoll::fmap_t sready;
int brdy;
// This keeps the number of links that existed at the entry.
// Simply notify all dead links, regardless as to whether the number
// of group members decreases below. If the number of corpses reaches
// this number, consider the group connection broken.
const size_t nlinks = m_Group.size();
size_t ndead = 0;
RetryWaitBlocked:
{
// Some sockets could have been closed in the meantime.
if (m_Global.m_EPoll.empty(*m_SndEpolld))
{
HLOGC(gslog.Debug, log << "grp/sendBackup: no more sockets available for sending - group broken");
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
}
InvertedLock ug(m_GroupLock);
HLOGC(gslog.Debug,
log << "grp/sendBackup: swait call to get at least one link alive up to " << m_iSndTimeOut << "us");
THREAD_PAUSED();
brdy = m_Global.m_EPoll.swait(*m_SndEpolld, (sready), m_iSndTimeOut);
THREAD_RESUMED();
if (brdy == 0) // SND timeout exceeded
{
throw CUDTException(MJ_AGAIN, MN_WRAVAIL, 0);
}
HLOGC(gslog.Debug, log << "grp/sendBackup: swait exited with " << brdy << " ready sockets:");
// Check if there's anything in the "error" section.
// This must be cleared here before the lock on group is set again.
// (This loop will not fire neither once if no failed sockets found).
for (CEPoll::fmap_t::const_iterator i = sready.begin(); i != sready.end(); ++i)
{
if (i->second & SRT_EPOLL_ERR)
{
SRTSOCKET id = i->first;
CUDTSocket* s = m_Global.locateSocket(id, CUDTUnited::ERH_RETURN); // << LOCKS m_GlobControlLock!
if (s)
{
HLOGC(gslog.Debug,
log << "grp/sendBackup: swait/ex on @" << (id)
<< " while waiting for any writable socket - CLOSING");
CUDT::uglobal().close(s); // << LOCKS m_GlobControlLock, then GroupLock!
}
else
{
HLOGC(gslog.Debug, log << "grp/sendBackup: swait/ex on @" << (id) << " - WAS DELETED IN THE MEANTIME");
}
++ndead;
}
}
HLOGC(gslog.Debug, log << "grp/sendBackup: swait/?close done, re-acquiring GroupLock");
}
// GroupLock is locked back
// Re-check after the waiting lock has been reacquired
if (m_bClosing)
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
if (brdy == -1 || ndead >= nlinks)
{
LOGC(gslog.Error,
log << "grp/sendBackup: swait=>" << brdy << " nlinks=" << nlinks << " ndead=" << ndead
<< " - looxlike all links broken");
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_OUT, false);
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_ERR, true);
// You can safely throw here - nothing to fill in when all sockets down.
// (timeout was reported by exception in the swait call).
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
}
// Ok, now check if we have at least one write-ready.
// Note that the procedure of activation of a new link in case of
// no stable links found embraces also rexmit-sending and status
// check as well, including blocked status.
// Find which one it was. This is so rare case that we can
// suffer linear search.
int nwaiting = 0;
int nactivated SRT_ATR_UNUSED = 0;
int stat = -1;
for (gli_t d = m_Group.begin(); d != m_Group.end(); ++d)
{
// We are waiting only for active members
if (d->sndstate != SRT_GST_RUNNING)
{
HLOGC(gslog.Debug,
log << "grp/sendBackup: member @" << d->id << " state is not RUNNING - SKIPPING from retry/waiting");
continue;
}
// Skip if not writable in this run
if (!CEPoll::isready(sready, d->id, SRT_EPOLL_OUT))
{
++nwaiting;
HLOGC(gslog.Debug, log << "grp/sendBackup: @" << d->id << " NOT ready:OUT, added as waiting");
continue;
}
try
{
// Note: this will set the currently required packet
// because it has been just freshly added to the sender buffer
stat = sendBackupRexmit(d->ps->core(), (w_mc));
++nactivated;
}
catch (CUDTException& e)
{
// This will be propagated from internal sendmsg2 call,
// but that's ok - we want this sending interrupted even in half.
w_cx = e;
stat = -1;
}
d->sndresult = stat;
d->laststatus = d->ps->getStatus();
if (stat == -1)
{
// This link is no longer waiting.
continue;
}
w_final_stat = stat;
d->sndstate = SRT_GST_RUNNING;
w_none_succeeded = false;
const steady_clock::time_point currtime = steady_clock::now();
sendBackup_AssignBackupState(d->ps->core(), BKUPST_ACTIVE_UNSTABLE_WARY, currtime);
w_sendBackupCtx.updateMemberState(&(*d), BKUPST_ACTIVE_UNSTABLE_WARY);
HLOGC(gslog.Debug, log << "grp/sendBackup: after waiting, ACTIVATED link @" << d->id);
break;
}
// If we have no links successfully activated, but at least
// one link "not ready for writing", continue waiting for at
// least one link ready.
if (stat == -1 && nwaiting > 0)
{
HLOGC(gslog.Debug, log << "grp/sendBackup: still have " << nwaiting << " waiting and none succeeded, REPEAT");
goto RetryWaitBlocked;
}
}
// [[using locked(this->m_GroupLock)]]
void CUDTGroup::sendBackup_SilenceRedundantLinks(SendBackupCtx& w_sendBackupCtx, const steady_clock::time_point& currtime)
{
// The most important principle is to keep the data being sent constantly,
// even if it means temporarily full redundancy.
// A member can be silenced only if there is at least one stable memebr.
const unsigned num_stable = w_sendBackupCtx.countMembersByState(BKUPST_ACTIVE_STABLE);
if (num_stable == 0)
return;
// INPUT NEEDED:
// - stable member with maximum weight
uint16_t max_weight_stable = 0;
SRTSOCKET stableSocketId = SRT_INVALID_SOCK; // SocketID of a stable link with higher weight
w_sendBackupCtx.sortByWeightAndState();
//LOGC(gslog.Debug, log << "grp/silenceRedundant: links after sort: " << w_sendBackupCtx.printMembers());
typedef vector<BackupMemberStateEntry>::const_iterator const_iter_t;
for (const_iter_t member = w_sendBackupCtx.memberStates().begin(); member != w_sendBackupCtx.memberStates().end(); ++member)
{
if (!isStateActive(member->state))
continue;
const bool haveHigherWeightStable = stableSocketId != SRT_INVALID_SOCK;
const uint16_t weight = member->pSocketData->weight;
if (member->state == BKUPST_ACTIVE_STABLE)
{
// silence stable link if it is not the first stable
if (!haveHigherWeightStable)
{
max_weight_stable = (int) weight;
stableSocketId = member->socketID;
continue;
}
else
{
LOGC(gslog.Note, log << "grp/sendBackup: silencing stable member @" << member->socketID << " (weight " << weight
<< ") in favor of @" << stableSocketId << " (weight " << max_weight_stable << ")");
}
}
else if (haveHigherWeightStable && weight <= max_weight_stable)
{
LOGC(gslog.Note, log << "grp/sendBackup: silencing member @" << member->socketID << " (weight " << weight
<< " " << stateToStr(member->state)
<< ") in favor of @" << stableSocketId << " (weight " << max_weight_stable << ")");
}
else
{
continue;
}
// TODO: Move to a separate function sendBackup_SilenceMember
SocketData* d = member->pSocketData;
CUDT& u = d->ps->core();
sendBackup_AssignBackupState(u, BKUPST_STANDBY, currtime);
w_sendBackupCtx.updateMemberState(d, BKUPST_STANDBY);
if (d->sndstate != SRT_GST_RUNNING)
{
LOGC(gslog.Error,
log << "grp/sendBackup: IPE: misidentified a non-running link @" << d->id << " as active");
continue;
}
d->sndstate = SRT_GST_IDLE;
}
}
int CUDTGroup::sendBackup(const char* buf, int len, SRT_MSGCTRL& w_mc)
{
if (len <= 0)
{
throw CUDTException(MJ_NOTSUP, MN_INVAL, 0);
}
// Only live streaming is supported
if (len > SRT_LIVE_MAX_PLSIZE)
{
LOGC(gslog.Error, log << "grp/send(backup): buffer size=" << len << " exceeds maximum allowed in live mode");
throw CUDTException(MJ_NOTSUP, MN_INVAL, 0);
}
// [[using assert(this->m_pSndBuffer != nullptr)]];
// First, acquire GlobControlLock to make sure all member sockets still exist
enterCS(m_Global.m_GlobControlLock);
ScopedLock guard(m_GroupLock);
if (m_bClosing)
{
leaveCS(m_Global.m_GlobControlLock);
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
}
// Now, still under lock, check if all sockets still can be dispatched
send_CheckValidSockets();
leaveCS(m_Global.m_GlobControlLock);
steady_clock::time_point currtime = steady_clock::now();
SendBackupCtx sendBackupCtx; // default initialized as empty
// TODO: reserve? sendBackupCtx.memberStates.reserve(m_Group.size());
sendBackup_QualifyMemberStates((sendBackupCtx), currtime);
int32_t curseq = SRT_SEQNO_NONE;
size_t nsuccessful = 0;
SRT_ATR_UNUSED CUDTException cx(MJ_SUCCESS, MN_NONE, 0); // TODO: Delete then?
uint16_t maxActiveWeight = 0; // Maximum weight of active links.
// The number of bytes sent or -1 for error will be stored in group_send_result
int group_send_result = sendBackup_SendOverActive(buf, len, w_mc, currtime, (curseq), (nsuccessful), (maxActiveWeight), (sendBackupCtx), (cx));
bool none_succeeded = (nsuccessful == 0);
// Save current payload in group's sender buffer.
sendBackup_Buffering(buf, len, (curseq), (w_mc));
sendBackup_TryActivateStandbyIfNeeded(buf, len, (none_succeeded),
(w_mc),
(curseq),
(group_send_result),
(sendBackupCtx),
(cx), currtime);
sendBackup_CheckPendingSockets((sendBackupCtx), currtime);
sendBackup_CheckUnstableSockets((sendBackupCtx), currtime);
//LOGC(gslog.Debug, log << "grp/sendBackup: links after all checks: " << sendBackupCtx.printMembers());
// Re-check after the waiting lock has been reacquired
if (m_bClosing)
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
sendBackup_CloseBrokenSockets((sendBackupCtx));
// Re-check after the waiting lock has been reacquired
if (m_bClosing)
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
// If all links out of the unstable-running links are blocked (SRT_EASYNCSND),
// perform epoll wait on them. In this situation we know that
// there are no idle blocked links because IDLE LINK CAN'T BE BLOCKED,
// no matter what. It's because the link may only be blocked if
// the sender buffer of this socket is full, and it can't be
// full if it wasn't used so far.
//
// This means that in case when we have no stable links, we
// need to try out any link that can accept the rexmit-load.
// We'll check link stability at the next sending attempt.
sendBackup_RetryWaitBlocked((sendBackupCtx), (group_send_result), (none_succeeded), (w_mc), (cx));
sendBackup_SilenceRedundantLinks((sendBackupCtx), currtime);
// (closing condition checked inside this call)
if (none_succeeded)
{
HLOGC(gslog.Debug, log << "grp/sendBackup: all links broken (none succeeded to send a payload)");
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_OUT, false);
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_ERR, true);
// Reparse error code, if set.
// It might be set, if the last operation was failed.
// If any operation succeeded, this will not be executed anyway.
throw CUDTException(MJ_CONNECTION, MN_CONNLOST, 0);
}
// At least one link has succeeded, update sending stats.
m_stats.sent.count(len);
// Now fill in the socket table. Check if the size is enough, if not,
// then set the pointer to NULL and set the correct size.
// Note that list::size() is linear time, however this shouldn't matter,
// as with the increased number of links in the redundancy group the
// impossibility of using that many of them grows exponentally.
const size_t grpsize = m_Group.size();
if (w_mc.grpdata_size < grpsize)
{
w_mc.grpdata = NULL;
}
size_t i = 0;
bool ready_again = false;
HLOGC(gslog.Debug, log << "grp/sendBackup: copying group data");
for (gli_t d = m_Group.begin(); d != m_Group.end(); ++d, ++i)
{
if (w_mc.grpdata)
{
// Enough space to fill
copyGroupData(*d, (w_mc.grpdata[i]));
}
// We perform this loop anyway because we still need to check if any
// socket is writable. Note that the group lock will hold any write ready
// updates that are performed just after a single socket update for the
// group, so if any socket is actually ready at the moment when this
// is performed, and this one will result in none-write-ready, this will
// be fixed just after returning from this function.
ready_again = ready_again || d->ps->writeReady();
}
w_mc.grpdata_size = i;
if (!ready_again)
{
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_OUT, false);
}
HLOGC(gslog.Debug,
log << "grp/sendBackup: successfully sent " << group_send_result << " bytes, "
<< (ready_again ? "READY for next" : "NOT READY to send next"));
return group_send_result;
}
// [[using locked(this->m_GroupLock)]]
int32_t CUDTGroup::addMessageToBuffer(const char* buf, size_t len, SRT_MSGCTRL& w_mc)
{
if (m_iSndAckedMsgNo == SRT_MSGNO_NONE)
{
// Very first packet, just set the msgno.
m_iSndAckedMsgNo = w_mc.msgno;
m_iSndOldestMsgNo = w_mc.msgno;
HLOGC(gslog.Debug, log << "addMessageToBuffer: initial message no #" << w_mc.msgno);
}
else if (m_iSndOldestMsgNo != m_iSndAckedMsgNo)
{
int offset = MsgNo(m_iSndAckedMsgNo) - MsgNo(m_iSndOldestMsgNo);
HLOGC(gslog.Debug,
log << "addMessageToBuffer: new ACK-ed messages: #(" << m_iSndOldestMsgNo << "-" << m_iSndAckedMsgNo
<< ") - going to remove");
if (offset > int(m_SenderBuffer.size()))
{
LOGC(gslog.Error,
log << "addMessageToBuffer: IPE: offset=" << offset << " exceeds buffer size=" << m_SenderBuffer.size()
<< " - CLEARING");
m_SenderBuffer.clear();
}
else
{
HLOGC(gslog.Debug,
log << "addMessageToBuffer: erasing " << offset << "/" << m_SenderBuffer.size()
<< " group-senderbuffer ACKED messages for #" << m_iSndOldestMsgNo << " - #" << m_iSndAckedMsgNo);
m_SenderBuffer.erase(m_SenderBuffer.begin(), m_SenderBuffer.begin() + offset);
}
// Position at offset is not included
m_iSndOldestMsgNo = m_iSndAckedMsgNo;
HLOGC(gslog.Debug,
log << "addMessageToBuffer: ... after: oldest #" << m_iSndOldestMsgNo);
}
m_SenderBuffer.resize(m_SenderBuffer.size() + 1);
BufferedMessage& bm = m_SenderBuffer.back();
bm.mc = w_mc;
bm.copy(buf, len);
HLOGC(gslog.Debug,
log << "addMessageToBuffer: #" << w_mc.msgno << " size=" << len << " !" << BufferStamp(buf, len));
return m_SenderBuffer.front().mc.pktseq;
}
int CUDTGroup::sendBackup_SendOverActive(const char* buf, int len, SRT_MSGCTRL& w_mc, const steady_clock::time_point& currtime, int32_t& w_curseq,
size_t& w_nsuccessful, uint16_t& w_maxActiveWeight, SendBackupCtx& w_sendBackupCtx, CUDTException& w_cx)
{
if (w_mc.srctime == 0)
w_mc.srctime = count_microseconds(currtime.time_since_epoch());
SRT_ASSERT(w_nsuccessful == 0);
SRT_ASSERT(w_maxActiveWeight == 0);
int group_send_result = SRT_ERROR;
// TODO: implement iterator over active links
typedef vector<BackupMemberStateEntry>::const_iterator const_iter_t;
for (const_iter_t member = w_sendBackupCtx.memberStates().begin(); member != w_sendBackupCtx.memberStates().end(); ++member)
{
if (!isStateActive(member->state))
continue;
SocketData* d = member->pSocketData;
int erc = SRT_SUCCESS;
// Remaining sndstate is SRT_GST_RUNNING. Send a payload through it.
CUDT& u = d->ps->core();
const int32_t lastseq = u.schedSeqNo();
int sndresult = SRT_ERROR;
try
{
// This must be wrapped in try-catch because on error it throws an exception.
// Possible return values are only 0, in case when len was passed 0, or a positive
// >0 value that defines the size of the data that it has sent, that is, in case
// of Live mode, equal to 'len'.
sndresult = u.sendmsg2(buf, len, (w_mc));
}
catch (CUDTException& e)
{
w_cx = e;
erc = e.getErrorCode();
sndresult = SRT_ERROR;
}
const bool send_succeeded = sendBackup_CheckSendStatus(
currtime,
sndresult,
lastseq,
w_mc.pktseq,
(u),
(w_curseq),
(group_send_result));
if (send_succeeded)
{
++w_nsuccessful;
w_maxActiveWeight = max(w_maxActiveWeight, d->weight);
if (u.m_pSndBuffer)
w_sendBackupCtx.setRateEstimate(u.m_pSndBuffer->getRateEstimator());
}
else if (erc == SRT_EASYNCSND)
{
sendBackup_AssignBackupState(u, BKUPST_ACTIVE_UNSTABLE, currtime);
w_sendBackupCtx.updateMemberState(d, BKUPST_ACTIVE_UNSTABLE);
}
d->sndresult = sndresult;
d->laststatus = d->ps->getStatus();
}
return group_send_result;
}
// [[using locked(this->m_GroupLock)]]
int CUDTGroup::sendBackupRexmit(CUDT& core, SRT_MSGCTRL& w_mc)
{
// This should resend all packets
if (m_SenderBuffer.empty())
{
LOGC(gslog.Fatal, log << "IPE: sendBackupRexmit: sender buffer empty");
// Although act as if it was successful, otherwise you'll get connection break
return 0;
}
// using [[assert !m_SenderBuffer.empty()]];
// Send everything you currently have in the sender buffer.
// The receiver will reject packets that it currently has.
// Start from the oldest.
CPacket packet;
set<int> results;
int stat = -1;
// Make sure that the link has correctly synchronized sequence numbers.
// Note that sequence numbers should be recorded in mc.
int32_t curseq = m_SenderBuffer[0].mc.pktseq;
size_t skip_initial = 0;
if (curseq != core.schedSeqNo())
{
const int distance = CSeqNo::seqoff(core.schedSeqNo(), curseq);
if (distance < 0)
{
// This may happen in case when the link to be activated is already running.
// Getting sequences backwards is not allowed, as sending them makes no
// sense - they are already ACK-ed or are behind the ISN. Instead, skip all
// packets that are in the past towards the scheduling sequence.
skip_initial = -distance;
LOGC(gslog.Warn,
log << "sendBackupRexmit: OVERRIDE attempt. Link seqno %" << core.schedSeqNo() << ", trying to send from seqno %" << curseq
<< " - DENIED; skip " << skip_initial << " pkts, " << m_SenderBuffer.size() << " pkts in buffer");
}
else
{
// In case when the next planned sequence on this link is behind
// the firstmost sequence in the backup buffer, synchronize the
// sequence with it first so that they go hand-in-hand with
// sequences already used by the link from which packets were
// copied to the backup buffer.
IF_HEAVY_LOGGING(int32_t old = core.schedSeqNo());
const bool su SRT_ATR_UNUSED = core.overrideSndSeqNo(curseq);
HLOGC(gslog.Debug,
log << "sendBackupRexmit: OVERRIDING seq %" << old << " with %" << curseq
<< (su ? " - succeeded" : " - FAILED!"));
}
}
if (skip_initial >= m_SenderBuffer.size())
{
LOGC(gslog.Warn,
log << "sendBackupRexmit: All packets were skipped. Nothing to send %" << core.schedSeqNo() << ", trying to send from seqno %" << curseq
<< " - DENIED; skip " << skip_initial << " packets");
return 0; // can't return any other state, nothing was sent
}
senderBuffer_t::iterator i = m_SenderBuffer.begin() + skip_initial;
// Send everything - including the packet freshly added to the buffer
for (; i != m_SenderBuffer.end(); ++i)
{
// NOTE: an exception from here will interrupt the loop
// and will be caught in the upper level.
stat = core.sendmsg2(i->data, (int)i->size, (i->mc));
if (stat == -1)
{
// Stop sending if one sending ended up with error
LOGC(gslog.Warn,
log << "sendBackupRexmit: sending from buffer stopped at %" << core.schedSeqNo() << " and FAILED");
return -1;
}
}
// Copy the contents of the last item being updated.
w_mc = m_SenderBuffer.back().mc;
HLOGC(gslog.Debug, log << "sendBackupRexmit: pre-sent collected %" << curseq << " - %" << w_mc.pktseq);
return stat;
}
// [[using locked(CUDTGroup::m_GroupLock)]];
void CUDTGroup::ackMessage(int32_t msgno)
{
// The message id could not be identified, skip.
if (msgno == SRT_MSGNO_CONTROL)
{
HLOGC(gslog.Debug, log << "ackMessage: msgno not found in ACK-ed sequence");
return;
}
// It's impossible to get the exact message position as the
// message is allowed also to span for multiple packets.
// Search since the oldest packet until you hit the first
// packet with this message number.
// First, you need to decrease the message number by 1. It's
// because the sequence number being ACK-ed can be in the middle
// of the message, while it doesn't acknowledge that the whole
// message has been received. Decrease the message number so that
// partial-message-acknowledgement does not swipe the whole message,
// part of which may need to be retransmitted over a backup link.
int offset = MsgNo(msgno) - MsgNo(m_iSndAckedMsgNo);
if (offset <= 0)
{
HLOGC(gslog.Debug, log << "ackMessage: already acked up to msgno=" << msgno);
return;
}
HLOGC(gslog.Debug, log << "ackMessage: updated to #" << msgno);
// Update last acked. Will be picked up when adding next message.
m_iSndAckedMsgNo = msgno;
}
void CUDTGroup::processKeepalive(CUDTGroup::SocketData* gli)
{
// received keepalive for that group member
// In backup group it means that the link went IDLE.
if (m_type == SRT_GTYPE_BACKUP)
{
if (gli->rcvstate == SRT_GST_RUNNING)
{
gli->rcvstate = SRT_GST_IDLE;
HLOGC(gslog.Debug, log << "GROUP: received KEEPALIVE in @" << gli->id << " - link turning rcv=IDLE");
}
// When received KEEPALIVE, the sending state should be also
// turned IDLE, if the link isn't temporarily activated. The
// temporarily activated link will not be measured stability anyway,
// while this should clear out the problem when the transmission is
// stopped and restarted after a while. This will simply set the current
// link as IDLE on the sender when the peer sends a keepalive because the
// data stopped coming in and it can't send ACKs therefore.
//
// This also shouldn't be done for the temporary activated links because
// stability timeout could be exceeded for them by a reason that, for example,
// the packets come with the past sequences (as they are being synchronized
// the sequence per being IDLE and empty buffer), so a large portion of initial
// series of packets may come with past sequence, delaying this way with ACK,
// which may result not only with exceeded stability timeout (which fortunately
// isn't being measured in this case), but also with receiveing keepalive
// (therefore we also don't reset the link to IDLE in the temporary activation period).
if (gli->sndstate == SRT_GST_RUNNING && is_zero(gli->ps->core().m_tsFreshActivation))
{
gli->sndstate = SRT_GST_IDLE;
HLOGC(gslog.Debug,
log << "GROUP: received KEEPALIVE in @" << gli->id << " active=PAST - link turning snd=IDLE");
}
}
}
void CUDTGroup::internalKeepalive(SocketData* gli)
{
// This is in response to AGENT SENDING keepalive. This means that there's
// no transmission in either direction, but the KEEPALIVE packet from the
// other party could have been missed. This is to ensure that the IDLE state
// is recognized early enough, before any sequence discrepancy can happen.
if (m_type == SRT_GTYPE_BACKUP && gli->rcvstate == SRT_GST_RUNNING)
{
gli->rcvstate = SRT_GST_IDLE;
// Prevent sending KEEPALIVE again in group-sending
gli->ps->core().m_tsFreshActivation = steady_clock::time_point();
HLOGC(gslog.Debug, log << "GROUP: EXP-requested KEEPALIVE in @" << gli->id << " - link turning IDLE");
}
}
CUDTGroup::BufferedMessageStorage CUDTGroup::BufferedMessage::storage(SRT_LIVE_MAX_PLSIZE /*, 1000*/);
// Forwarder needed due to class definition order
int32_t CUDTGroup::generateISN()
{
return CUDT::generateISN();
}
void CUDTGroup::setGroupConnected()
{
if (!m_bConnected)
{
// Switch to connected state and give appropriate signal
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_CONNECT, true);
m_bConnected = true;
}
}
void CUDTGroup::updateLatestRcv(CUDTSocket* s)
{
// Currently only Backup groups use connected idle links.
if (m_type != SRT_GTYPE_BACKUP)
return;
HLOGC(grlog.Debug,
log << "updateLatestRcv: BACKUP group, updating from active link @" << s->m_SocketID << " with %"
<< s->core().m_iRcvLastAck);
CUDT* source = &s->core();
vector<CUDT*> targets;
UniqueLock lg(m_GroupLock);
// Sanity check for a case when getting a deleted socket
if (!s->m_GroupOf)
return;
// Under a group lock, we block execution of removal of the socket
// from the group, so if m_GroupOf is not NULL, we are granted
// that m_GroupMemberData is valid.
SocketData* current = s->m_GroupMemberData;
for (gli_t gi = m_Group.begin(); gi != m_Group.end(); ++gi)
{
// Skip the socket that has reported packet reception
if (&*gi == current)
{
HLOGC(grlog.Debug, log << "grp: NOT updating rcv-seq on self @" << gi->id);
continue;
}
// Don't update the state if the link is:
// - PENDING - because it's not in the connected state, wait for it.
// - RUNNING - because in this case it should have its own line of sequences
// - BROKEN - because it doesn't make sense anymore, about to be removed
if (gi->rcvstate != SRT_GST_IDLE)
{
HLOGC(grlog.Debug,
log << "grp: NOT updating rcv-seq on @" << gi->id
<< " - link state:" << srt_log_grp_state[gi->rcvstate]);
continue;
}
// Sanity check
if (!gi->ps->core().m_bConnected)
{
HLOGC(grlog.Debug, log << "grp: IPE: NOT updating rcv-seq on @" << gi->id << " - IDLE BUT NOT CONNECTED");
continue;
}
targets.push_back(&gi->ps->core());
}
lg.unlock();
// Do this on the unlocked group because this
// operation will need receiver lock, so it might
// risk a deadlock.
for (size_t i = 0; i < targets.size(); ++i)
{
targets[i]->updateIdleLinkFrom(source);
}
}
void CUDTGroup::activateUpdateEvent(bool still_have_items)
{
// This function actually reacts on the fact that a socket
// was deleted from the group. This might make the group empty.
if (!still_have_items) // empty, or removal of unknown socket attempted - set error on group
{
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_IN | SRT_EPOLL_OUT | SRT_EPOLL_ERR, true);
}
else
{
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_UPDATE, true);
}
}
void CUDTGroup::addEPoll(int eid)
{
enterCS(m_Global.m_EPoll.m_EPollLock);
m_sPollID.insert(eid);
leaveCS(m_Global.m_EPoll.m_EPollLock);
bool any_read = false;
bool any_write = false;
bool any_broken = false;
bool any_pending = false;
{
// Check all member sockets
ScopedLock gl(m_GroupLock);
// We only need to know if there is any socket that is
// ready to get a payload and ready to receive from.
for (gli_t i = m_Group.begin(); i != m_Group.end(); ++i)
{
if (i->sndstate == SRT_GST_IDLE || i->sndstate == SRT_GST_RUNNING)
{
any_write |= i->ps->writeReady();
}
if (i->rcvstate == SRT_GST_IDLE || i->rcvstate == SRT_GST_RUNNING)
{
any_read |= i->ps->readReady();
}
if (i->ps->broken())
any_broken |= true;
else
any_pending |= true;
}
}
// This is stupid, but we don't have any other interface to epoll
// internals. Actually we don't have to check if id() is in m_sPollID
// because we know it is, as we just added it. But it's not performance
// critical, sockets are not being often added during transmission.
if (any_read)
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_IN, true);
if (any_write)
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_OUT, true);
// Set broken if none is non-broken (pending, read-ready or write-ready)
if (any_broken && !any_pending)
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_ERR, true);
}
void CUDTGroup::removeEPollEvents(const int eid)
{
// clear IO events notifications;
// since this happens after the epoll ID has been removed, they cannot be set again
set<int> remove;
remove.insert(eid);
m_Global.m_EPoll.update_events(id(), remove, SRT_EPOLL_IN | SRT_EPOLL_OUT, false);
}
void CUDTGroup::removeEPollID(const int eid)
{
enterCS(m_Global.m_EPoll.m_EPollLock);
m_sPollID.erase(eid);
leaveCS(m_Global.m_EPoll.m_EPollLock);
}
void CUDTGroup::updateFailedLink()
{
ScopedLock lg(m_GroupLock);
// Check all members if they are in the pending
// or connected state.
int nhealthy = 0;
for (gli_t i = m_Group.begin(); i != m_Group.end(); ++i)
{
if (i->sndstate < SRT_GST_BROKEN)
nhealthy++;
}
if (!nhealthy)
{
// No healthy links, set ERR on epoll.
HLOGC(gmlog.Debug, log << "group/updateFailedLink: All sockets broken");
m_Global.m_EPoll.update_events(id(), m_sPollID, SRT_EPOLL_IN | SRT_EPOLL_OUT | SRT_EPOLL_ERR, true);
}
else
{
HLOGC(gmlog.Debug, log << "group/updateFailedLink: Still " << nhealthy << " links in the group");
}
}
#if ENABLE_HEAVY_LOGGING
// [[using maybe_locked(CUDT::uglobal()->m_GlobControlLock)]]
void CUDTGroup::debugGroup()
{
ScopedLock gg(m_GroupLock);
HLOGC(gmlog.Debug, log << "GROUP MEMBER STATUS - $" << id());
for (gli_t gi = m_Group.begin(); gi != m_Group.end(); ++gi)
{
HLOGC(gmlog.Debug,
log << " ... id { agent=@" << gi->id << " peer=@" << gi->ps->m_PeerID
<< " } address { agent=" << gi->agent.str() << " peer=" << gi->peer.str() << "} "
<< " state {snd=" << StateStr(gi->sndstate) << " rcv=" << StateStr(gi->rcvstate) << "}");
}
}
#endif
} // namespace srt