Attach TransportFeedbackPacketLossTracker to ANA (PLR only)

webrtc/modules/congestion_controller/transport_feedback_adapter.cc

Index: webrtc/modules/congestion_controller/transport_feedback_adapter.cc
diff --git a/webrtc/modules/congestion_controller/transport_feedback_adapter.cc b/webrtc/modules/congestion_controller/transport_feedback_adapter.cc
index ddffa7219692be1580bb64046779a245bcdb3c79..123067070799392bb7c5a544a2dae932ef777c14 100644
--- a/webrtc/modules/congestion_controller/transport_feedback_adapter.cc
+++ b/webrtc/modules/congestion_controller/transport_feedback_adapter.cc
@@ -36,19 +36,55 @@ TransportFeedbackAdapter::TransportFeedbackAdapter(const Clock* clock)
       local_net_id_(0),
       remote_net_id_(0) {}
 
-TransportFeedbackAdapter::~TransportFeedbackAdapter() {}
+TransportFeedbackAdapter::~TransportFeedbackAdapter() {
+  RTC_DCHECK(observers_.empty());
+}
+
+void TransportFeedbackAdapter::RegisterTransportFeedbackAdapterObserver(
+    TransportFeedbackAdapterObserver* observer) {
+  rtc::CritScope cs(&observers_lock_);
+  RTC_DCHECK(observer);
+  if (std::find(observers_.begin(), observers_.end(), observer) ==
+      observers_.end()) {
+    observers_.push_back(observer);
+  } else {
+    RTC_NOTREACHED();
+  }
+}
 
-void TransportFeedbackAdapter::AddPacket(uint16_t sequence_number,
+void TransportFeedbackAdapter::DeRegisterTransportFeedbackAdapterObserver(
+    TransportFeedbackAdapterObserver* observer) {
+  rtc::CritScope cs(&observers_lock_);
+  RTC_DCHECK(observer);
+  auto elem = std::find(observers_.begin(), observers_.end(), observer);

[minyue-webrtc, 2017/03/17 09:20:31]

elem -> it

[elad.alon_webrtc.org, 2017/03/17 10:10:33]

Will do.

+  if (elem != observers_.end()) {

[minyue-webrtc, 2017/03/17 09:20:31]

RTC_DCHECK_NE(observers_.end(), it);

[elad.alon_webrtc.org, 2017/03/17 10:10:33]

Will do.

[elad.alon_webrtc.org, 2017/03/17 13:40:06]

Minyue, FYI, the RTC_DCHECK_EQ/_NE doesn't seem to work well with these
iterators, so I'll be using a generic RTC_DCHECK. Something with the
stringification of the arguments; I've not dug deeper because I don't think it's
in-scope. Let me know if you think this should be looked more into.

[minyue-webrtc, 2017/03/21 09:22:58]

RTC_DCHECK( xx != xx) is fine. Thanks.

+    observers_.erase(elem);
+  } else {
+    RTC_NOTREACHED();
+  }
+}
+
+void TransportFeedbackAdapter::AddPacket(uint32_t ssrc,
+                                         uint16_t sequence_number,
                                          size_t length,
                                          const PacedPacketInfo& pacing_info) {
-  rtc::CritScope cs(&lock_);
-  if (send_side_bwe_with_overhead_) {
-    length += transport_overhead_bytes_per_packet_;
+  {
+    rtc::CritScope cs(&lock_);

[minyue-webrtc, 2017/03/17 09:20:31]

lock_ as a name becomes unclear

[elad.alon_webrtc.org, 2017/03/17 10:10:33]

Stefan, do you have a specific name you'd like?

[stefan-webrtc, 2017/03/21 11:35:47]

Not really since it's a generic lock used for a bunch of things. feedback_lock_
maybe... Not much better.

[minyue-webrtc, 2017/03/21 11:36:51]

Acknowledged.

+    if (send_side_bwe_with_overhead_) {
+      length += transport_overhead_bytes_per_packet_;
+    }
+    const int64_t creation_time_ms = clock_->TimeInMilliseconds();
+    send_time_history_.AddAndRemoveOld(
+        PacketFeedback(creation_time_ms, sequence_number, length, local_net_id_,
+                       remote_net_id_, pacing_info));
+  }
+
+  {
+    rtc::CritScope cs(&observers_lock_);
+    for (auto observer : observers_) {
+      observer->OnPacketAdded(ssrc, sequence_number);
+    }
   }
-  const int64_t creation_time_ms = clock_->TimeInMilliseconds();
-  send_time_history_.AddAndRemoveOld(
-      PacketFeedback(creation_time_ms, sequence_number, length, local_net_id_,
-                     remote_net_id_, pacing_info));
 }
 
 void TransportFeedbackAdapter::OnSentPacket(uint16_t sequence_number,
@@ -154,6 +190,12 @@ std::vector<PacketFeedback> TransportFeedbackAdapter::GetPacketFeedbackVector(
 void TransportFeedbackAdapter::OnTransportFeedback(
     const rtcp::TransportFeedback& feedback) {
   last_packet_feedback_vector_ = GetPacketFeedbackVector(feedback);
+  {
+    rtc::CritScope cs(&observers_lock_);
+    for (auto observer : observers_) {
+      observer->OnTransportFeedback(feedback);
+    }
+  }
 }
 
 std::vector<PacketFeedback>