Fix error handling in RTPReceiver.Receive

If we failed to startReceive we would still make the Receiver as ready
to start reading.
    
Fixes #2929

peerconnection_renegotiation_test.go

@@ -1127,10 +1127,13 @@ func TestPeerConnection_Renegotiation_Simulcast(t *testing.T) {
 		defer trackMapLock.Unlock()
 
 		for _, track := range trackMap {
-			_, _, err := track.ReadRTP() // Ignore first Read, this is our peeked data
+			_, _, err := track.ReadRTP()
-			assert.Nil(t, err)
+
+			// Ignore first Read, this was our peeked data
+			if err == nil {
+				_, _, err = track.ReadRTP()
+			}
 
-			_, _, err = track.ReadRTP()
 			assert.Equal(t, err, io.EOF)
 		}
 	}

rtpreceiver.go

@@ -193,7 +193,6 @@ func (r *RTPReceiver) startReceive(parameters RTPReceiveParameters) error { //no
 		return errRTPReceiverReceiveAlreadyCalled
 	default:
 	}
-	defer close(r.received)
 
 	globalParams := r.getParameters()
 	codec := RTPCodecCapability{}
@@ -257,6 +256,8 @@ func (r *RTPReceiver) startReceive(parameters RTPReceiveParameters) error { //no
 		}
 	}
 
+	close(r.received)
+
 	return nil
 }
 
@@ -404,7 +405,12 @@ func (r *RTPReceiver) streamsForTrack(t *TrackRemote) *trackStreams {
 
 // readRTP should only be called by a track, this only exists so we can keep state in one place.
 func (r *RTPReceiver) readRTP(b []byte, reader *TrackRemote) (n int, a interceptor.Attributes, err error) {
-	<-r.received
+	select {
+	case <-r.received:
+	case <-r.closed:
+		return 0, nil, io.EOF
+	}
+
 	if t := r.streamsForTrack(reader); t != nil {
 		return t.rtpInterceptor.Read(b, a)
 	}

rtpreceiver_go_test.go

@@ -8,6 +8,7 @@ package webrtc
 
 import (
 	"context"
+	"io"
 	"testing"
 	"time"
 
@@ -74,3 +75,38 @@ func TestSetRTPParameters(t *testing.T) {
 	assert.NoError(t, wan.Stop())
 	closePairNow(t, sender, receiver)
 }
+
+func TestReceiveError(t *testing.T) {
+	api := NewAPI()
+
+	dtlsTransport, err := api.NewDTLSTransport(nil, nil)
+	assert.NoError(t, err)
+
+	rtpReceiver, err := api.NewRTPReceiver(RTPCodecTypeVideo, dtlsTransport)
+	assert.NoError(t, err)
+
+	rtpParameters := RTPReceiveParameters{
+		Encodings: []RTPDecodingParameters{
+			{
+				RTPCodingParameters: RTPCodingParameters{
+					SSRC: 1000,
+				},
+			},
+		},
+	}
+
+	assert.Error(t, rtpReceiver.Receive(rtpParameters))
+
+	chanErrs := make(chan error)
+	go func() {
+		_, _, chanErr := rtpReceiver.Read(nil)
+		chanErrs <- chanErr
+
+		_, _, chanErr = rtpReceiver.Track().ReadRTP()
+		chanErrs <- chanErr
+	}()
+
+	assert.NoError(t, rtpReceiver.Stop())
+	assert.Error(t, io.ErrClosedPipe, <-chanErrs)
+	assert.Error(t, io.ErrClosedPipe, <-chanErrs)
+}