quicr / libquicr

Transport based on QuicR API

QuicR

THiS REPO IS NOT UNDER ACTIVE DEVELOPMENT

libquicr's Issues

Deadlock in QuicRClientRawSession

The session_mutex is locked when unsubscribe() is called. That then calls removeSubscribeState()

void
QuicRClientRawSession::unsubscribe(const quicr::Namespace& quicr_namespace,
                                   const std::string& /* origin_url */,
                                   const std::string& /* auth_token */)
{
  // The removal of the delegate is done on receive of subscription ended
  std::lock_guard<std::mutex> lock(session_mutex);

  messages::MessageBuffer msg{};
  messages::Unsubscribe unsub{ 0x1, quicr_namespace };
  msg << unsub;

  removeSubscribeState(quicr_namespace,
                       SubscribeResult::SubscribeStatus::ConnectionClosed);
  transport->enqueue(transport_context_id, transport_stream_id, msg.take());
}

And removeSubscribeState() is this:

void
QuicRClientRawSession::removeSubscribeState(
  const quicr::Namespace& quicr_namespace,
  const SubscribeResult::SubscribeStatus& reason)
{
  std::lock_guard<std::mutex> _(session_mutex);

  if (!!subscribe_state.count(quicr_namespace)) {
    subscribe_state.erase(quicr_namespace);
  }

  if (!!sub_delegates.count(quicr_namespace)) {
    if (auto sub_delegate = sub_delegates[quicr_namespace].lock())
      sub_delegate->onSubscriptionEnded(quicr_namespace, reason);

    sub_delegates.erase(quicr_namespace);
  }
}

The same mutex is locked again.

One of the two needs to be removed. I'd suggest removing it from unsubscribe(), as it doesn't appear to be necessary there.

Refine pub/sub api

Transport not obeying shutdown while connecting

When told to disconnect, if the transport is in the middle of trying to connect, everything else obeys he command, but transport keeps on connecting away, until it times out finally, and realizes it was told to shutdown.

Steps to reproduce (using Decimus):

• Set relay address to somewhere random where it could never possibly connect.
• Attempt to connect to a meeting
• Leave the meeting while it is connecting
• Watch logs, transport will still be logging it is trying to connect (at least with QUIC)

UDP actually just seems to keep trying forever and ever, never lets go.

First discussed: #56 (comment)

Allocation of buffer size bug

https://github.com/Quicr/libquicr/blob/main/src/quicr_client_raw_session.cpp#L232

The sizeof() may or may not be the right choice, but use of payload.size() here is wrong since payload was moved.

Crash in `on_recv_notify`

I don't have much detail here, dropping this so I don't forget. I saw a crash in the following on teardown.

#0	0x0000000104ea129c in quicr::QuicRTransportDelegate::on_recv_notify(unsigned long long const&, unsigned long long const&) ()

This seems to happen in conjunction when there's another weird issue, where I'm seemingly getting loss or the relay is running very slowly even locally. When that's happening, I always get the above on teardown.

qmedia`quicr::QuicRTransportDelegate::on_recv_notify:
    0x105585248 <+0>:   sub    sp, sp, #0x140
    0x10558524c <+4>:   stp    x28, x27, [sp, #0x120]
    0x105585250 <+8>:   stp    x29, x30, [sp, #0x130]
    0x105585254 <+12>:  add    x29, sp, #0x130
    0x105585258 <+16>:  stur   x0, [x29, #-0x18]
    0x10558525c <+20>:  stur   x1, [x29, #-0x20]
    0x105585260 <+24>:  stur   x2, [x29, #-0x28]
    0x105585264 <+28>:  ldur   x8, [x29, #-0x18]
    0x105585268 <+32>:  str    x8, [sp, #0x38]
    0x10558526c <+36>:  stur   wzr, [x29, #-0x2c]
    0x105585270 <+40>:  b      0x105585274               ; <+44>
    0x105585274 <+44>:  ldur   w8, [x29, #-0x2c]
    0x105585278 <+48>:  subs   w8, w8, #0x96
    0x10558527c <+52>:  b.ge   0x1055855cc               ; <+900>
    0x105585280 <+56>:  b      0x105585284               ; <+60>
    0x105585284 <+60>:  ldr    x8, [sp, #0x38]
    0x105585288 <+64>:  ldr    x8, [x8, #0x8]
    0x10558528c <+68>:  add    x0, x8, #0x8
    0x105585290 <+72>:  bl     0x10557d290               ; std::__1::shared_ptr<qtransport::ITransport>::operator->() const
    0x105585294 <+76>:  ldur   x1, [x29, #-0x20]
    0x105585298 <+80>:  ldur   x2, [x29, #-0x28]
->  0x10558529c <+84>:  ldr    x8, [x0] EXC_BAD_ACCESS (code=1, address=0x0)