Refactor RtpSender and SSRCDatabase a bit.

webrtc/modules/rtp_rtcp/source/rtp_sender.cc

Index: webrtc/modules/rtp_rtcp/source/rtp_sender.cc
diff --git a/webrtc/modules/rtp_rtcp/source/rtp_sender.cc b/webrtc/modules/rtp_rtcp/source/rtp_sender.cc
index bd9314d5d768b6e2d30c5be2a4ef2287b9c35ef5..0a83944e45d1bffc8c967d5d8130b584c7119c8c 100644
--- a/webrtc/modules/rtp_rtcp/source/rtp_sender.cc
+++ b/webrtc/modules/rtp_rtcp/source/rtp_sender.cc
@@ -63,56 +63,46 @@ uint32_t ConvertMsTo24Bits(int64_t time_ms) {
 }
 }  // namespace
 
-class BitrateAggregator {
- public:
-  explicit BitrateAggregator(BitrateStatisticsObserver* bitrate_callback)
-      : callback_(bitrate_callback),
-        total_bitrate_observer_(*this),
-        retransmit_bitrate_observer_(*this),
-        ssrc_(0) {}
-
-  void OnStatsUpdated() const {
-    if (callback_)
-      callback_->Notify(total_bitrate_observer_.statistics(),
-                        retransmit_bitrate_observer_.statistics(),
-                        ssrc_);
-  }
-
-  Bitrate::Observer* total_bitrate_observer() {
-    return &total_bitrate_observer_;
-  }
-  Bitrate::Observer* retransmit_bitrate_observer() {
-    return &retransmit_bitrate_observer_;
-  }
-
-  void set_ssrc(uint32_t ssrc) { ssrc_ = ssrc; }
-
- private:
-  // We assume that these observers are called on the same thread, which is
-  // true for RtpSender as they are called on the Process thread.
-  class BitrateObserver : public Bitrate::Observer {
-   public:
-    explicit BitrateObserver(const BitrateAggregator& aggregator)
-        : aggregator_(aggregator) {}
-
-    // Implements Bitrate::Observer.
-    void BitrateUpdated(const BitrateStatistics& stats) override {
-      statistics_ = stats;
-      aggregator_.OnStatsUpdated();
-    }
+RTPSender::BitrateAggregator::BitrateAggregator(
+    BitrateStatisticsObserver* bitrate_callback)
+    : callback_(bitrate_callback),
+      total_bitrate_observer_(*this),
+      retransmit_bitrate_observer_(*this),
+      ssrc_(0) {}
 
-    BitrateStatistics statistics() const { return statistics_; }
+void RTPSender::BitrateAggregator::OnStatsUpdated() const {
+  if (callback_) {
+    callback_->Notify(total_bitrate_observer_.statistics(),
+                      retransmit_bitrate_observer_.statistics(), ssrc_);
+  }
+}
 
-   private:
-    BitrateStatistics statistics_;
-    const BitrateAggregator& aggregator_;
-  };
+Bitrate::Observer* RTPSender::BitrateAggregator::total_bitrate_observer() {
+  return &total_bitrate_observer_;
+}
+Bitrate::Observer* RTPSender::BitrateAggregator::retransmit_bitrate_observer() {
+  return &retransmit_bitrate_observer_;
+}
 
-  BitrateStatisticsObserver* const callback_;
-  BitrateObserver total_bitrate_observer_;
-  BitrateObserver retransmit_bitrate_observer_;
-  uint32_t ssrc_;
-};
+void RTPSender::BitrateAggregator::set_ssrc(uint32_t ssrc) {
+  ssrc_ = ssrc;
+}
+
+RTPSender::BitrateAggregator::BitrateObserver::BitrateObserver(
+    const BitrateAggregator& aggregator)
+    : aggregator_(aggregator) {}
+
+// Implements Bitrate::Observer.
+void RTPSender::BitrateAggregator::BitrateObserver::BitrateUpdated(
+    const BitrateStatistics& stats) {
+  statistics_ = stats;
+  aggregator_.OnStatsUpdated();
+}
+
+const BitrateStatistics&
+RTPSender::BitrateAggregator::BitrateObserver::statistics() const {
+  return statistics_;
+}
 
 RTPSender::RTPSender(
     bool audio,
@@ -132,8 +122,8 @@ RTPSender::RTPSender(
       clock_delta_ms_(clock_->TimeInMilliseconds() -
                       TickTime::MillisecondTimestamp()),
       random_(clock_->TimeInMicroseconds()),
-      bitrates_(new BitrateAggregator(bitrate_callback)),
-      total_bitrate_sent_(clock, bitrates_->total_bitrate_observer()),
+      bitrates_(bitrate_callback),
+      total_bitrate_sent_(clock, bitrates_.total_bitrate_observer()),
       audio_configured_(audio),
       audio_(audio ? new RTPSenderAudio(clock, this, audio_feedback) : nullptr),
       video_(audio ? nullptr : new RTPSenderVideo(clock, this)),
@@ -141,7 +131,6 @@ RTPSender::RTPSender(
       transport_sequence_number_allocator_(sequence_number_allocator),
       transport_feedback_observer_(transport_feedback_observer),
       last_capture_time_ms_sent_(0),
-      send_critsect_(CriticalSectionWrapper::CreateCriticalSection()),
       transport_(transport),
       sending_media_(true),                      // Default to sending media.
       max_payload_length_(IP_PACKET_SIZE - 28),  // Default is IP-v4/UDP.
@@ -157,7 +146,7 @@ RTPSender::RTPSender(
       // NACK.
       nack_byte_count_times_(),
       nack_byte_count_(),
-      nack_bitrate_(clock, bitrates_->retransmit_bitrate_observer()),
+      nack_bitrate_(clock, bitrates_.retransmit_bitrate_observer()),
       packet_history_(clock),
       // Statistics
       statistics_crit_(CriticalSectionWrapper::CreateCriticalSection()),
@@ -168,7 +157,7 @@ RTPSender::RTPSender(
       // RTP variables
       start_timestamp_forced_(false),
       start_timestamp_(0),
-      ssrc_db_(*SSRCDatabase::GetSSRCDatabase()),
+      ssrc_db_(SSRCDatabase::GetSSRCDatabase()),
       remote_ssrc_(0),
       sequence_number_forced_(false),
       ssrc_forced_(false),
@@ -184,21 +173,35 @@ RTPSender::RTPSender(
       target_bitrate_(0) {
   memset(nack_byte_count_times_, 0, sizeof(nack_byte_count_times_));
   memset(nack_byte_count_, 0, sizeof(nack_byte_count_));
-  // We need to seed the random generator.
+  // We need to seed the random generator for BuildPaddingPacket() below.
+  // TODO(holmer,tommi): Note that TimeInMilliseconds might return 0 on Mac
+  // early on in the process.
   srand(static_cast<uint32_t>(clock_->TimeInMilliseconds()));
-  ssrc_ = ssrc_db_.CreateSSRC();  // Can't be 0.
-  ssrc_rtx_ = ssrc_db_.CreateSSRC();  // Can't be 0.
-  bitrates_->set_ssrc(ssrc_);
+  ssrc_ = ssrc_db_->CreateSSRC();
+  RTC_DCHECK(ssrc_);
+  ssrc_rtx_ = ssrc_db_->CreateSSRC();
+  RTC_DCHECK(ssrc_rtx_);
+
+  bitrates_.set_ssrc(ssrc_);
   // Random start, 16 bits. Can't be 0.
   sequence_number_rtx_ = random_.Rand(1, kMaxInitRtpSeqNumber);
   sequence_number_ = random_.Rand(1, kMaxInitRtpSeqNumber);
 }
 
 RTPSender::~RTPSender() {
+  // TODO(tommi): Use a thread checker to ensure the object is created and
+  // deleted on the same thread.  At the moment this isn't possible due to
+  // voe::ChannelOwner in voice engine.  To reproduce, run:
+  // voe_auto_test --automated --gtest_filter=*MixManyChannelsForStressOpus
+
+  // TODO(tommi,holmer): We don't grab locks in the dtor before accessing member
+  // variables but we grab them in all other methods. (what's the design?)
+  // Start documenting what thread we're on in what method so that it's easier
+  // to understand performance attributes and possibly remove locks.
   if (remote_ssrc_ != 0) {
-    ssrc_db_.ReturnSSRC(remote_ssrc_);
+    ssrc_db_->ReturnSSRC(remote_ssrc_);
   }
-  ssrc_db_.ReturnSSRC(ssrc_);
+  ssrc_db_->ReturnSSRC(ssrc_);
 
   SSRCDatabase::ReturnSSRCDatabase();
   while (!payload_type_map_.empty()) {
@@ -246,7 +249,7 @@ int32_t RTPSender::SetTransmissionTimeOffset(int32_t transmission_time_offset) {
       transmission_time_offset < -(0x800000 - 1)) {  // Word24.
     return -1;
   }
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   transmission_time_offset_ = transmission_time_offset;
   return 0;
 }
@@ -255,25 +258,25 @@ int32_t RTPSender::SetAbsoluteSendTime(uint32_t absolute_send_time) {
   if (absolute_send_time > 0xffffff) {  // UWord24.
     return -1;
   }
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   absolute_send_time_ = absolute_send_time;
   return 0;
 }
 
 void RTPSender::SetVideoRotation(VideoRotation rotation) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   rotation_ = rotation;
 }
 
 int32_t RTPSender::SetTransportSequenceNumber(uint16_t sequence_number) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   transport_sequence_number_ = sequence_number;
   return 0;
 }
 
 int32_t RTPSender::RegisterRtpHeaderExtension(RTPExtensionType type,
                                               uint8_t id) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   if (type == kRtpExtensionVideoRotation) {
     cvo_mode_ = kCVOInactive;
     return rtp_header_extension_map_.RegisterInactive(type, id);
@@ -282,17 +285,17 @@ int32_t RTPSender::RegisterRtpHeaderExtension(RTPExtensionType type,
 }
 
 bool RTPSender::IsRtpHeaderExtensionRegistered(RTPExtensionType type) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   return rtp_header_extension_map_.IsRegistered(type);
 }
 
 int32_t RTPSender::DeregisterRtpHeaderExtension(RTPExtensionType type) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   return rtp_header_extension_map_.Deregister(type);
 }
 
 size_t RTPSender::RtpHeaderExtensionTotalLength() const {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   return rtp_header_extension_map_.GetTotalLengthInBytes();
 }
 
@@ -303,7 +306,7 @@ int32_t RTPSender::RegisterPayload(
     size_t channels,
     uint32_t rate) {
   assert(payload_name);
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   std::map<int8_t, RtpUtility::Payload*>::iterator it =
       payload_type_map_.find(payload_number);
@@ -346,7 +349,7 @@ int32_t RTPSender::RegisterPayload(
 }
 
 int32_t RTPSender::DeRegisterSendPayload(int8_t payload_type) {
-  CriticalSectionScoped lock(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   std::map<int8_t, RtpUtility::Payload*>::iterator it =
       payload_type_map_.find(payload_type);
@@ -361,12 +364,12 @@ int32_t RTPSender::DeRegisterSendPayload(int8_t payload_type) {
 }
 
 void RTPSender::SetSendPayloadType(int8_t payload_type) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   payload_type_ = payload_type;
 }
 
 int8_t RTPSender::SendPayloadType() const {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   return payload_type_;
 }
 
@@ -379,7 +382,7 @@ int32_t RTPSender::SetMaxPayloadLength(size_t max_payload_length,
   // Sanity check.
   RTC_DCHECK(max_payload_length >= 100 && max_payload_length <= IP_PACKET_SIZE)
       << "Invalid max payload length: " << max_payload_length;
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   max_payload_length_ = max_payload_length;
   packet_over_head_ = packet_over_head;
   return 0;
@@ -388,7 +391,7 @@ int32_t RTPSender::SetMaxPayloadLength(size_t max_payload_length,
 size_t RTPSender::MaxDataPayloadLength() const {
   int rtx;
   {
-    CriticalSectionScoped rtx_lock(send_critsect_.get());
+    rtc::CritScope lock(&send_critsect_);
     rtx = rtx_;
   }
   if (audio_configured_) {
@@ -407,28 +410,28 @@ size_t RTPSender::MaxPayloadLength() const {
 uint16_t RTPSender::PacketOverHead() const { return packet_over_head_; }
 
 void RTPSender::SetRtxStatus(int mode) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   rtx_ = mode;
 }
 
 int RTPSender::RtxStatus() const {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   return rtx_;
 }
 
 void RTPSender::SetRtxSsrc(uint32_t ssrc) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   ssrc_rtx_ = ssrc;
 }
 
 uint32_t RTPSender::RtxSsrc() const {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   return ssrc_rtx_;
 }
 
 void RTPSender::SetRtxPayloadType(int payload_type,
                                   int associated_payload_type) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   RTC_DCHECK_LE(payload_type, 127);
   RTC_DCHECK_LE(associated_payload_type, 127);
   if (payload_type < 0) {
@@ -441,7 +444,7 @@ void RTPSender::SetRtxPayloadType(int payload_type,
 }
 
 std::pair<int, int> RTPSender::RtxPayloadType() const {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   for (const auto& kv : rtx_payload_type_map_) {
     if (kv.second == rtx_payload_type_) {
       return std::make_pair(rtx_payload_type_, kv.first);
@@ -452,7 +455,7 @@ std::pair<int, int> RTPSender::RtxPayloadType() const {
 
 int32_t RTPSender::CheckPayloadType(int8_t payload_type,
                                     RtpVideoCodecTypes* video_type) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   if (payload_type < 0) {
     LOG(LS_ERROR) << "Invalid payload_type " << payload_type;
@@ -494,7 +497,7 @@ int32_t RTPSender::CheckPayloadType(int8_t payload_type,
 
 RTPSenderInterface::CVOMode RTPSender::ActivateCVORtpHeaderExtension() {
   if (cvo_mode_ == kCVOInactive) {
-    CriticalSectionScoped cs(send_critsect_.get());
+    rtc::CritScope lock(&send_critsect_);
     if (rtp_header_extension_map_.SetActive(kRtpExtensionVideoRotation, true)) {
       cvo_mode_ = kCVOActivated;
     }
@@ -513,7 +516,7 @@ int32_t RTPSender::SendOutgoingData(FrameType frame_type,
   uint32_t ssrc;
   {
     // Drop this packet if we're not sending media packets.
-    CriticalSectionScoped cs(send_critsect_.get());
+    rtc::CritScope lock(&send_critsect_);
     ssrc = ssrc_;
     if (!sending_media_) {
       return 0;
@@ -565,7 +568,7 @@ int32_t RTPSender::SendOutgoingData(FrameType frame_type,
 
 size_t RTPSender::TrySendRedundantPayloads(size_t bytes_to_send) {
   {
-    CriticalSectionScoped cs(send_critsect_.get());
+    rtc::CritScope lock(&send_critsect_);
     if ((rtx_ & kRtxRedundantPayloads) == 0)
       return 0;
   }
@@ -627,7 +630,7 @@ size_t RTPSender::SendPadData(size_t bytes,
     int payload_type;
     bool over_rtx;
     {
-      CriticalSectionScoped cs(send_critsect_.get());
+      rtc::CritScope lock(&send_critsect_);
       if (!timestamp_provided) {
         timestamp = timestamp_;
         capture_time_ms = capture_time_ms_;
@@ -741,7 +744,7 @@ int32_t RTPSender::ReSendPacket(uint16_t packet_id, int64_t min_resend_time) {
   }
   int rtx = kRtxOff;
   {
-    CriticalSectionScoped lock(send_critsect_.get());
+    rtc::CritScope lock(&send_critsect_);
     rtx = rtx_;
   }
   if (!PrepareAndSendPacket(data_buffer, length, capture_time_ms,
@@ -839,7 +842,7 @@ bool RTPSender::ProcessNACKBitRate(uint32_t now) {
   const uint32_t kAvgIntervalMs = 1000;
   uint32_t target_bitrate = GetTargetBitrate();
 
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   if (target_bitrate == 0) {
     return true;
@@ -864,7 +867,7 @@ bool RTPSender::ProcessNACKBitRate(uint32_t now) {
 }
 
 void RTPSender::UpdateNACKBitRate(uint32_t bytes, int64_t now) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   if (bytes == 0)
     return;
   nack_bitrate_.Update(bytes);
@@ -900,7 +903,7 @@ bool RTPSender::TimeToSendPacket(uint16_t sequence_number,
   }
   int rtx;
   {
-    CriticalSectionScoped lock(send_critsect_.get());
+    rtc::CritScope lock(&send_critsect_);
     rtx = rtx_;
   }
   return PrepareAndSendPacket(data_buffer,
@@ -958,7 +961,7 @@ bool RTPSender::PrepareAndSendPacket(uint8_t* buffer,
 
   bool ret = SendPacketToNetwork(buffer_to_send_ptr, length, options);
   if (ret) {
-    CriticalSectionScoped lock(send_critsect_.get());
+    rtc::CritScope lock(&send_critsect_);
     media_has_been_sent_ = true;
   }
   UpdateRtpStats(buffer_to_send_ptr, length, rtp_header, send_over_rtx,
@@ -1018,7 +1021,7 @@ size_t RTPSender::TimeToSendPadding(size_t bytes) {
   if (audio_configured_ || bytes == 0)
     return 0;
   {
-    CriticalSectionScoped cs(send_critsect_.get());
+    rtc::CritScope lock(&send_critsect_);
     if (!sending_media_)
       return 0;
   }
@@ -1090,7 +1093,7 @@ int32_t RTPSender::SendToNetwork(uint8_t* buffer,
     return -1;
 
   {
-    CriticalSectionScoped lock(send_critsect_.get());
+    rtc::CritScope lock(&send_critsect_);
     media_has_been_sent_ = true;
   }
   UpdateRtpStats(buffer, length, rtp_header, false, false);
@@ -1105,7 +1108,7 @@ void RTPSender::UpdateDelayStatistics(int64_t capture_time_ms, int64_t now_ms) {
   int avg_delay_ms = 0;
   int max_delay_ms = 0;
   {
-    CriticalSectionScoped lock(send_critsect_.get());
+    rtc::CritScope lock(&send_critsect_);
     ssrc = ssrc_;
   }
   {
@@ -1131,7 +1134,7 @@ void RTPSender::UpdateDelayStatistics(int64_t capture_time_ms, int64_t now_ms) {
 }
 
 void RTPSender::ProcessBitrate() {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   total_bitrate_sent_.Process();
   nack_bitrate_.Process();
   if (audio_configured_) {
@@ -1141,7 +1144,7 @@ void RTPSender::ProcessBitrate() {
 }
 
 size_t RTPSender::RTPHeaderLength() const {
-  CriticalSectionScoped lock(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   size_t rtp_header_length = kRtpHeaderLength;
   rtp_header_length += sizeof(uint32_t) * csrcs_.size();
   rtp_header_length += RtpHeaderExtensionTotalLength();
@@ -1149,7 +1152,7 @@ size_t RTPSender::RTPHeaderLength() const {
 }
 
 uint16_t RTPSender::AllocateSequenceNumber(uint16_t packets_to_send) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   uint16_t first_allocated_sequence_number = sequence_number_;
   sequence_number_ += packets_to_send;
   return first_allocated_sequence_number;
@@ -1208,7 +1211,7 @@ int32_t RTPSender::BuildRTPheader(uint8_t* data_buffer,
                                   bool timestamp_provided,
                                   bool inc_sequence_number) {
   assert(payload_type >= 0);
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   if (timestamp_provided) {
     timestamp_ = start_timestamp_ + capture_timestamp;
@@ -1515,7 +1518,7 @@ void RTPSender::UpdateTransmissionTimeOffset(uint8_t* rtp_packet,
                                              const RTPHeader& rtp_header,
                                              int64_t time_diff_ms) const {
   size_t offset;
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   switch (VerifyExtension(kRtpExtensionTransmissionTimeOffset, rtp_packet,
                           rtp_packet_length, rtp_header,
                           kTransmissionTimeOffsetLength, &offset)) {
@@ -1541,7 +1544,7 @@ bool RTPSender::UpdateAudioLevel(uint8_t* rtp_packet,
                                  bool is_voiced,
                                  uint8_t dBov) const {
   size_t offset;
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   switch (VerifyExtension(kRtpExtensionAudioLevel, rtp_packet,
                           rtp_packet_length, rtp_header, kAudioLevelLength,
@@ -1566,7 +1569,7 @@ bool RTPSender::UpdateVideoRotation(uint8_t* rtp_packet,
                                     const RTPHeader& rtp_header,
                                     VideoRotation rotation) const {
   size_t offset;
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   switch (VerifyExtension(kRtpExtensionVideoRotation, rtp_packet,
                           rtp_packet_length, rtp_header, kVideoRotationLength,
@@ -1591,7 +1594,7 @@ void RTPSender::UpdateAbsoluteSendTime(uint8_t* rtp_packet,
                                        const RTPHeader& rtp_header,
                                        int64_t now_ms) const {
   size_t offset;
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   switch (VerifyExtension(kRtpExtensionAbsoluteSendTime, rtp_packet,
                           rtp_packet_length, rtp_header,
@@ -1618,7 +1621,7 @@ uint16_t RTPSender::UpdateTransportSequenceNumber(
     size_t rtp_packet_length,
     const RTPHeader& rtp_header) const {
   size_t offset;
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   switch (VerifyExtension(kRtpExtensionTransportSequenceNumber, rtp_packet,
                           rtp_packet_length, rtp_header,
@@ -1647,12 +1650,13 @@ void RTPSender::SetSendingStatus(bool enabled) {
     // Will be ignored if it's already configured via API.
     SetStartTimestamp(RTPtime, false);
   } else {
-    CriticalSectionScoped lock(send_critsect_.get());
+    rtc::CritScope lock(&send_critsect_);
     if (!ssrc_forced_) {
       // Generate a new SSRC.
-      ssrc_db_.ReturnSSRC(ssrc_);
-      ssrc_ = ssrc_db_.CreateSSRC();  // Can't be 0.
-      bitrates_->set_ssrc(ssrc_);
+      ssrc_db_->ReturnSSRC(ssrc_);
+      ssrc_ = ssrc_db_->CreateSSRC();
+      RTC_DCHECK(ssrc_);

[stefan-webrtc, 2016/01/26 13:19:52]

I prefer > 0 or != 0.

[tommi, 2016/01/30 10:53:41]

Done.

+      bitrates_.set_ssrc(ssrc_);
     }
     // Don't initialize seq number if SSRC passed externally.
     if (!sequence_number_forced_ && !ssrc_forced_) {
@@ -1663,22 +1667,22 @@ void RTPSender::SetSendingStatus(bool enabled) {
 }
 
 void RTPSender::SetSendingMediaStatus(bool enabled) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   sending_media_ = enabled;
 }
 
 bool RTPSender::SendingMedia() const {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   return sending_media_;
 }
 
 uint32_t RTPSender::Timestamp() const {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   return timestamp_;
 }
 
 void RTPSender::SetStartTimestamp(uint32_t timestamp, bool force) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   if (force) {
     start_timestamp_forced_ = true;
     start_timestamp_ = timestamp;
@@ -1690,58 +1694,59 @@ void RTPSender::SetStartTimestamp(uint32_t timestamp, bool force) {
 }
 
 uint32_t RTPSender::StartTimestamp() const {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   return start_timestamp_;
 }
 
 uint32_t RTPSender::GenerateNewSSRC() {
   // If configured via API, return 0.
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   if (ssrc_forced_) {
     return 0;
   }
-  ssrc_ = ssrc_db_.CreateSSRC();  // Can't be 0.
-  bitrates_->set_ssrc(ssrc_);
+  ssrc_ = ssrc_db_->CreateSSRC();
+  RTC_DCHECK(ssrc_);

[stefan-webrtc, 2016/01/26 13:19:52]

same here

[tommi, 2016/01/30 10:53:41]

Done.

+  bitrates_.set_ssrc(ssrc_);
   return ssrc_;
 }
 
 void RTPSender::SetSSRC(uint32_t ssrc) {
   // This is configured via the API.
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   if (ssrc_ == ssrc && ssrc_forced_) {
     return;  // Since it's same ssrc, don't reset anything.
   }
   ssrc_forced_ = true;
-  ssrc_db_.ReturnSSRC(ssrc_);
-  ssrc_db_.RegisterSSRC(ssrc);
+  ssrc_db_->ReturnSSRC(ssrc_);
+  ssrc_db_->RegisterSSRC(ssrc);
   ssrc_ = ssrc;
-  bitrates_->set_ssrc(ssrc_);
+  bitrates_.set_ssrc(ssrc_);
   if (!sequence_number_forced_) {
     sequence_number_ = random_.Rand(1, kMaxInitRtpSeqNumber);
   }
 }
 
 uint32_t RTPSender::SSRC() const {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   return ssrc_;
 }
 
 void RTPSender::SetCsrcs(const std::vector<uint32_t>& csrcs) {
   assert(csrcs.size() <= kRtpCsrcSize);
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   csrcs_ = csrcs;
 }
 
 void RTPSender::SetSequenceNumber(uint16_t seq) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   sequence_number_forced_ = true;
   sequence_number_ = seq;
 }
 
 uint16_t RTPSender::SequenceNumber() const {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   return sequence_number_;
 }
 
@@ -1818,7 +1823,7 @@ int32_t RTPSender::SetFecParameters(
 
 void RTPSender::BuildRtxPacket(uint8_t* buffer, size_t* length,
                                uint8_t* buffer_rtx) {
-  CriticalSectionScoped cs(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   uint8_t* data_buffer_rtx = buffer_rtx;
   // Add RTX header.
   RtpUtility::RtpHeaderParser rtp_parser(
@@ -1873,7 +1878,7 @@ uint32_t RTPSender::BitrateSent() const {
 
 void RTPSender::SetRtpState(const RtpState& rtp_state) {
   SetStartTimestamp(rtp_state.start_timestamp, true);
-  CriticalSectionScoped lock(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   sequence_number_ = rtp_state.sequence_number;
   sequence_number_forced_ = true;
   timestamp_ = rtp_state.timestamp;
@@ -1883,7 +1888,7 @@ void RTPSender::SetRtpState(const RtpState& rtp_state) {
 }
 
 RtpState RTPSender::GetRtpState() const {
-  CriticalSectionScoped lock(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   RtpState state;
   state.sequence_number = sequence_number_;
@@ -1897,12 +1902,12 @@ RtpState RTPSender::GetRtpState() const {
 }
 
 void RTPSender::SetRtxRtpState(const RtpState& rtp_state) {
-  CriticalSectionScoped lock(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
   sequence_number_rtx_ = rtp_state.sequence_number;
 }
 
 RtpState RTPSender::GetRtxRtpState() const {
-  CriticalSectionScoped lock(send_critsect_.get());
+  rtc::CritScope lock(&send_critsect_);
 
   RtpState state;
   state.sequence_number = sequence_number_rtx_;