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fix datachannel remote vs. local closing during client's peerconnection cleanup

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This commit is contained in:
Serene Han 2016-03-06 11:40:00 -08:00
parent 9daa6c4b71
commit 91673a4abe
1 changed files with 29 additions and 17 deletions
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46
client/webrtc.go
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@ -48,17 +48,7 @@ func (c *webRTCConn) Write(b []byte) (int, error) {
func (c *webRTCConn) Close() error {
var err error = nil
log.Printf("WebRTC: Closing")
if nil != c.snowflake {
s := c.snowflake
c.snowflake = nil
log.Printf("WebRTC: closing DataChannel")
s.Close()
}
if nil != c.pc {
log.Printf("WebRTC: closing PeerConnection")
err = c.pc.Close()
c.pc = nil
}
c.cleanup()
close(c.offerChannel)
close(c.answerChannel)
close(c.errorChannel)
@ -127,9 +117,12 @@ func (c *webRTCConn) ConnectLoop() {
<-c.reset
log.Println(" --- snowflake connection reset ---")
}
<-time.After(time.Second * 1)
c.cleanup()
}
}
// Create and prepare callbacks on a new WebRTC PeerConnection.
func (c *webRTCConn) preparePeerConnection() {
if nil != c.pc {
c.pc.Close()
@ -178,6 +171,9 @@ func (c *webRTCConn) preparePeerConnection() {
// Create a WebRTC DataChannel locally.
func (c *webRTCConn) establishDataChannel() error {
if c.snowflake != nil {
panic("Unexpected datachannel already exists!")
}
dc, err := c.pc.CreateDataChannel("snowflake", webrtc.Init{})
// Triggers "OnNegotiationNeeded" on the PeerConnection, which will prepare
// an SDP offer while other goroutines operating on this struct handle the
@ -201,20 +197,20 @@ func (c *webRTCConn) establishDataChannel() error {
c.snowflake = dc
}
dc.OnClose = func() {
// Disable the DataChannel as a write destination.
// Future writes will go to the buffer until a new DataChannel is available.
log.Println("WebRTC: DataChannel.OnClose")
// Only reset if this OnClose was triggered remotely.
if nil == c.snowflake {
panic("Should not have nil snowflake before closing. ")
// Closed locally, as part of a reset.
log.Println("WebRTC: DataChannel.OnClose [locally]")
return
}
// Closed remotely, need to reset everything.
// Disable the DataChannel as a write destination.
log.Println("WebRTC: DataChannel.OnClose [remotely]")
c.snowflake = nil
// TODO: Need a way to update the circuit so that when a new WebRTC
// data channel is available, the relay actually recognizes the new
// snowflake?
c.Reset()
// c.Close()
// c.endChannel <- struct{}{}
}
dc.OnMessage = func(msg []byte) {
// log.Println("ONMESSAGE: ", len(msg))
@ -290,3 +286,19 @@ func (c *webRTCConn) Reset() {
log.Println("WebRTC resetting...")
}()
}
func (c *webRTCConn) cleanup() {
if nil != c.snowflake {
s := c.snowflake
log.Printf("WebRTC: closing DataChannel")
// Setting snowflak to nil *before* Close indicates to OnClose that it
// was locally triggered.
c.snowflake = nil
s.Close()
}
if nil != c.pc {
log.Printf("WebRTC: closing PeerConnection")
c.pc.Close()
c.pc = nil
}
}