From PR #1158 during negotiation every required transceiver is assigned
to a specific media section (using the media section mid value).
The same should be done when starting receivers. We should start the
receiver assigned to the media section of that track.
Only start senders that were negotiated.
Since `startTransports`/`startRenegotiation` start rtp senders in a
goroutine, an user could call AddTrack/Add*Transceiver/RemoveTrack
causing a not negotiated sender track ssrc to be started.
This tries to better match the JSEP spec and will fix at least two
issues:
* #1171
* #1178
* Move transceiver selection/creation in SetRemoteDescription and
CreateOffer
* In SetRemoteDescription also create new Transceivers of type recvonly
when no satisfying transceiver is available
* In CreateOffer generate unique mid in number format avoiding possible
collisions with remote provide mids and to also already handle a future
implementation of m= section rejection and reuse
* Now generateMatchedSDP will just find the transceivers with the
required mid since they are already selected previously.
More details in these extract from JSEP:
JSEP 5.10 (Applying a Remote Description) says:
```
For each m= section, the following steps MUST be performed
[...]
If the m= section is not associated with any RtpTransceiver
(possibly because it was dissociated in the previous step),
either find an RtpTransceiver or create one according to the
following steps:
```
JSEP 5.2 (Constructing an Offer) says:
```
[...]
An m= section is generated for each RtpTransceiver
that has been added to the PeerConnection, excluding any stopped
RtpTransceivers;
```
Note that we are currently directly associating a mid to a transceiver
in CreateOffer, instead the spec says to also keep a m= section index
mapping to a transceiver and set the transceiver mid only when applying
the local description. This is needed to support rollback of proposed
offer/answer but currently we don't have support and tests for rollback
situations.
In SetLocalDescription guard iceGatherer.Gather by checking state.
We don't put this check inside Gather because ORTC doesn't have the
function as re-entrant
Resolves#1144
Co-authored-by: jeremija
According to @at-wat's suggestions. In my previous commit, there was no
guarantee that the initial Track().id and Track().label would be set
before the second answer with a `a=msid` section was received.
During re-negotiation we didn't properly filter SSRCes that we had
already handled. This makes sure to loop the existing transceivers
and asserts we don't try to handle the same SSRC again.
Resolves#1122
Edge prechromium does not like app data section before video/audio.
It generates the following error:
0: Unable to get property 'state' of undefined or null reference
rtcpeerconnection.js (1016,1)
Each negotation must be finished before processing the next one.
Before we would process multiple calls at once, and since they are
performed async we would have undefined behavior.
Resolves#1074
Move this from Error -> Warn. Now that re-negotiation has landed users
will see this a lot more, and it isn't helpful by default. We still want
this message in case users are trying to debug if an OnTrack isn't
fired.
When offering always put application first. Before during re-negotation
we would break the order if media sections because we would always place
it last. Instead of remembering what order the application was place
just always place it first.
Resolves#1055
The data race detector detects a race if
PeerConnection.ConnectionState is called while
PeerConnection.updateConnectionState is changing
the connection state
Remove some duplication that makes re-negotiation harder.
By splitting parsing of inbound SDP and creation of outbound
it makes the next step a lot easier.
Relates to #207
Add a new public method, GetRegisteredRTPCodecs, under PeerConnection
to allow access to get the registered list of RTPCodec from the
underlying MediaEngine for developers who want to build libraries on
top of pion.
Resolves#966
Currently we error if a STUN URL passed to Configuration.ICEServers
contained a query parameter. Fix this by using the getICEServers
function that sanitizes these for us.
DataChannel readyState should be set to Closed on PeerConnection
shutdown. If not properly set it would attempt to interact with
state that doesn't exist after the PeerConnection has been Closed.
Setting the readyState is also clearly defined in the W3C webrtc-pc
Resolves#915
PeerConnection.Close() doesn't match the W3C RFC on closing,
re-order the transports so that they close in the proper order.
In the future we will use the DTLS Close alert and RTCP Bye to
better communicate shutdown
Use values directly from SettingValues instead of just copying
when calling NewICEGatherer. This greatly reduces the LoC and makes
the public API a little cleaner.
Resolves#872
Before we computed DataChannel IDs before signaling, this
is incorrect because IDs must take into account if we are
running an DTLS Client or Server.
This updates the DataChannel ID generation code to take this
into account before generating a streamId.
Resolves#908
