Fix datachannel id setting for 0.5.0 release (#237)

Author: stuqdog

examples/examples/ortc/ortc.rs

@@ -201,7 +201,7 @@ async fn main() -> Result<()> {
 
         let dc_params = DataChannelParameters {
             label: "Foo".to_owned(),
-            id,
+            negotiated: Some(id),
             ..Default::default()
         };
 

webrtc/src/data_channel/data_channel_init.rs

@@ -20,13 +20,10 @@ pub struct RTCDataChannelInit {
     pub protocol: Option<String>,
 
     /// negotiated describes if the data channel is created by the local peer or
-    /// the remote peer. The default value of false tells the user agent to
+    /// the remote peer. The default value of None tells the user agent to
     /// announce the channel in-band and instruct the other peer to dispatch a
-    /// corresponding DataChannel. If set to true, it is up to the application
+    /// corresponding DataChannel. If set to Some(id), it is up to the application
     /// to negotiate the channel and create an DataChannel with the same id
     /// at the other peer.
-    pub negotiated: Option<bool>,
-
-    /// id overrides the default selection of ID for this channel.
-    pub id: Option<u16>,
+    pub negotiated: Option<u16>,
 }

webrtc/src/data_channel/data_channel_parameters.rs

@@ -5,9 +5,8 @@ use serde::{Deserialize, Serialize};
 pub struct DataChannelParameters {
     pub label: String,
     pub protocol: String,
-    pub id: u16,
     pub ordered: bool,
     pub max_packet_life_time: u16,
     pub max_retransmits: u16,
-    pub negotiated: bool,
+    pub negotiated: Option<u16>,
 }

webrtc/src/data_channel/data_channel_test.rs

@@ -536,11 +536,9 @@ async fn test_data_channel_parameters_negotiated_exchange() -> Result<()> {
 
     const EXPECTED_MESSAGE: &str = "Hello World";
 
-    let negotiated = true;
     let id = 500u16;
     let options = RTCDataChannelInit {
-        negotiated: Some(negotiated),
-        id: Some(id),
+        negotiated: Some(id),
         ..Default::default()
     };
 
@@ -1523,10 +1521,9 @@ async fn test_data_channel_ortc_e2e() -> Result<()> {
 
     signal_ortc_pair(Arc::clone(&stack_a), Arc::clone(&stack_b)).await?;
 
-    let id = 1u16;
     let dc_params = DataChannelParameters {
         label: "Foo".to_owned(),
-        id,
+        negotiated: None,
         ..Default::default()
     };
 

webrtc/src/data_channel/mod.rs

@@ -86,6 +86,9 @@ pub struct RTCDataChannel {
 impl RTCDataChannel {
     // create the DataChannel object before the networking is set up.
     pub(crate) fn new(params: DataChannelParameters, setting_engine: Arc<SettingEngine>) -> Self {
+        // the id value if non-negotiated doesn't matter, since it will be overwritten
+        // on opening
+        let id = params.negotiated.unwrap_or(0);
         RTCDataChannel {
             stats_id: format!(
                 "DataChannel-{}",
@@ -95,8 +98,8 @@ impl RTCDataChannel {
             ),
             label: params.label,
             protocol: params.protocol,
-            negotiated: params.negotiated,
-            id: AtomicU16::new(params.id),
+            negotiated: params.negotiated.is_some(),
+            id: AtomicU16::new(id),
             ordered: params.ordered,
             max_packet_lifetime: params.max_packet_life_time,
             max_retransmits: params.max_retransmits,
@@ -157,7 +160,7 @@ impl RTCDataChannel {
                 negotiated: self.negotiated,
             };
 
-            if self.id.load(Ordering::SeqCst) == 0 {
+            if !self.negotiated {
                 self.id.store(
                     sctp_transport
                         .generate_and_set_data_channel_id(

webrtc/src/peer_connection/mod.rs

@@ -1857,10 +1857,6 @@ impl RTCPeerConnection {
 
         // https://w3c.github.io/webrtc-pc/#peer-to-peer-data-api (Step #19)
         if let Some(options) = options {
-            if let Some(id) = options.id {
-                params.id = id;
-            }
-
             // Ordered indicates if data is allowed to be delivered out of order. The
             // default value of true, guarantees that data will be delivered in order.
             // https://w3c.github.io/webrtc-pc/#peer-to-peer-data-api (Step #9)
@@ -1889,9 +1885,7 @@ impl RTCPeerConnection {
             }
 
             // https://w3c.github.io/webrtc-pc/#peer-to-peer-data-api (Step #12)
-            if let Some(negotiated) = options.negotiated {
-                params.negotiated = negotiated;
-            }
+            params.negotiated = options.negotiated;
         }
 
         let d = Arc::new(RTCDataChannel::new(

webrtc/src/sctp_transport/mod.rs

@@ -275,13 +275,16 @@ impl RTCSctpTransport {
                 }
             };
 
-            let id = dc.stream_identifier();
+            let negotiated = if dc.config.negotiated {
+                Some(dc.stream_identifier())
+            } else {
+                None
+            };
             let rtc_dc = Arc::new(RTCDataChannel::new(
                 DataChannelParameters {
-                    id,
                     label: dc.config.label.clone(),
                     protocol: dc.config.protocol.clone(),
-                    negotiated: dc.config.negotiated,
+                    negotiated,
                     ordered,
                     max_packet_life_time: max_packet_lifetime,
                     max_retransmits,