Moving MediaStreamSignaling logic into PeerConnection.

talk/app/webrtc/datachannel.cc

Index: talk/app/webrtc/datachannel.cc
diff --git a/talk/app/webrtc/datachannel.cc b/talk/app/webrtc/datachannel.cc
index 690ee65d3b713f9f8ee1257b3e48593aaaefd61e..0252d6580db73911fdf99e290802d0319d5a12ae 100644
--- a/talk/app/webrtc/datachannel.cc
+++ b/talk/app/webrtc/datachannel.cc
@@ -31,6 +31,7 @@
 
 #include "talk/app/webrtc/mediastreamprovider.h"
 #include "talk/app/webrtc/sctputils.h"
+#include "talk/media/sctp/sctpdataengine.h"
 #include "webrtc/base/logging.h"
 #include "webrtc/base/refcount.h"
 
@@ -43,6 +44,42 @@ enum {
   MSG_CHANNELREADY,
 };
 
+bool SctpSidAllocator::AllocateSctpSid(rtc::SSLRole role, int* sid) {

[pthatcher1, 2015/10/07 02:50:51]

Might as well remove "Sctp" from the method name and just call it AllocateSid,
ReserveSid, ReleaseSid, and IsSidAvailable.

[Taylor Brandstetter, 2015/10/09 19:54:08]

Done.

+  int potential_sid = (role == rtc::SSL_CLIENT) ? 0 : 1;
+  while (!IsSctpSidAvailable(potential_sid)) {
+    potential_sid += 2;
+    if (potential_sid > static_cast<int>(cricket::kMaxSctpSid)) {
+      return false;
+    }
+  }
+
+  *sid = potential_sid;
+  used_sids_.insert(potential_sid);
+  return true;
+}
+
+bool SctpSidAllocator::ReserveSctpSid(int sid) {
+  if (!IsSctpSidAvailable(sid)) {
+    return false;
+  }
+  used_sids_.insert(sid);
+  return true;
+}
+
+void SctpSidAllocator::ReleaseSctpSid(int sid) {
+  auto it = used_sids_.find(sid);
+  if (it != used_sids_.end()) {
+    used_sids_.erase(it);
+  }
+}
+
+bool SctpSidAllocator::IsSctpSidAvailable(int sid) const {
+  if (sid < 0 || sid > static_cast<int>(cricket::kMaxSctpSid)) {
+    return false;
+  }
+  return used_sids_.find(sid) == used_sids_.end();
+}
+
 DataChannel::PacketQueue::PacketQueue() : byte_count_(0) {}
 
 DataChannel::PacketQueue::~PacketQueue() {
@@ -361,6 +398,12 @@ void DataChannel::OnDataReceived(cricket::DataChannel* channel,
   }
 }
 
+void DataChannel::OnStreamClosedRemotely(uint32 sid) {

[Taylor Brandstetter, 2015/10/07 00:26:19]

Was previously MediaStreamSignaling::OnRemoteSctpDataChannelClosed.
The channel will be removed from the PeerConnection and sid released when it
calls SignalClosed so the behavior is the same.

+  if (data_channel_type_ == cricket::DCT_SCTP && sid == config_.id) {
+    Close();
+  }
+}
+
 void DataChannel::OnChannelReady(bool writable) {
   writable_ = writable;
   if (!writable) {
@@ -436,13 +479,17 @@ void DataChannel::UpdateState() {
 }
 
 void DataChannel::SetState(DataState state) {
-  if (state_ == state)
+  if (state_ == state) {
     return;
+  }
 
   state_ = state;
   if (observer_) {
     observer_->OnStateChange();
   }
+  if (state_ == kClosed) {
+    SignalClosed(this);
+  }
 }
 
 void DataChannel::DisconnectFromProvider() {