commit 8d3d6cf9089519add886d32e7839ea30074ac310
author Harald Alvestrand <hta@webrtc.org> Thu May 16 09:49:17 2019
committer Commit Bot <commit-bot@chromium.org> Thu May 16 11:03:17 2019
tree 3951ee5c489e1c71433420a3aae116f4054cb4ad
parent 6e70f18fbd13d4b2d84220b402a6a09e631a5c16

SCTP: Treat message size zero as "responder selects"

This also refactors some of the code in peerconnection for
handling SCTP transports to be internal to the webrtc::SctpTransport
class, rather than being in peerconnection.

Bug: webrtc:10358, webrtc:10629
Change-Id: I15ecf95c199f56b08909e5a9311d446a412ed162
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/137041
Reviewed-by: Henrik Boström <hbos@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#27960}

pc/sctp_transport.cc

diff --git a/pc/sctp_transport.cc b/pc/sctp_transport.cc
index d23d619..1c0289a9 100644
--- a/pc/sctp_transport.cc
+++ b/pc/sctp_transport.cc
@@ -96,6 +96,27 @@
   UpdateInformation(next_state);
 }
 
+void SctpTransport::Start(int local_port,
+                          int remote_port,
+                          int max_message_size) {
+  {
+    rtc::CritScope scope(&lock_);
+    // Record max message size on calling thread.
+    info_ = SctpTransportInformation(info_.state(), info_.dtls_transport(),
+                                     max_message_size, info_.MaxChannels());
+  }
+  if (owner_thread_->IsCurrent()) {
+    if (!internal()->Start(local_port, remote_port, max_message_size)) {
+      RTC_LOG(LS_ERROR) << "Failed to push down SCTP parameters, closing.";
+      UpdateInformation(SctpTransportState::kClosed);
+    }
+  } else {
+    owner_thread_->Invoke<void>(
+        RTC_FROM_HERE, rtc::Bind(&SctpTransport::Start, this, local_port,
+                                 remote_port, max_message_size));
+  }
+}
+
 void SctpTransport::UpdateInformation(SctpTransportState state) {
   RTC_DCHECK_RUN_ON(owner_thread_);
   bool must_send_update;
@@ -103,12 +124,11 @@
   {
     rtc::CritScope scope(&lock_);
     must_send_update = (state != info_.state());
-    // TODO(https://bugs.webrtc.org/10358): Update max message size and
-    // max channels from internal SCTP transport when available.
+    // TODO(https://bugs.webrtc.org/10358): Update max channels from internal
+    // SCTP transport when available.
     if (internal_sctp_transport_) {
       info_ = SctpTransportInformation(
-          state, dtls_transport_, internal_sctp_transport_->max_message_size(),
-          info_.MaxChannels());
+          state, dtls_transport_, info_.MaxMessageSize(), info_.MaxChannels());
     } else {
       info_ = SctpTransportInformation(
           state, dtls_transport_, info_.MaxMessageSize(), info_.MaxChannels());