Cast: Re-factor rtcp_sender.cc into rtcp_builder.cc and do some cleanup

media/cast/net/rtcp/rtcp_sender.cc

Index: media/cast/net/rtcp/rtcp_sender.cc
diff --git a/media/cast/net/rtcp/rtcp_sender.cc b/media/cast/net/rtcp/rtcp_sender.cc
deleted file mode 100644
index 4ca6eb581bd73c454766cfa90f989d925f2e9715..0000000000000000000000000000000000000000
--- a/media/cast/net/rtcp/rtcp_sender.cc
+++ /dev/null
@@ -1,636 +0,0 @@
-// Copyright 2014 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#include "media/cast/net/rtcp/rtcp_sender.h"
-
-#include <stdint.h>
-
-#include <algorithm>
-#include <vector>
-
-#include "base/big_endian.h"
-#include "base/logging.h"
-#include "media/cast/net/cast_transport_defines.h"
-#include "media/cast/net/pacing/paced_sender.h"
-#include "media/cast/net/rtcp/rtcp_defines.h"
-#include "media/cast/net/rtcp/rtcp_utility.h"
-
-namespace media {
-namespace cast {
-namespace {
-
-// Max delta is 4095 milliseconds because we need to be able to encode it in
-// 12 bits.
-const int64 kMaxWireFormatTimeDeltaMs = INT64_C(0xfff);
-
-uint16 MergeEventTypeAndTimestampForWireFormat(
-    const CastLoggingEvent& event,
-    const base::TimeDelta& time_delta) {
-  int64 time_delta_ms = time_delta.InMilliseconds();
-
-  DCHECK_GE(time_delta_ms, 0);
-  DCHECK_LE(time_delta_ms, kMaxWireFormatTimeDeltaMs);
-
-  uint16 time_delta_12_bits =
-      static_cast<uint16>(time_delta_ms & kMaxWireFormatTimeDeltaMs);
-
-  uint16 event_type_4_bits = ConvertEventTypeToWireFormat(event);
-  DCHECK(event_type_4_bits);
-  DCHECK(~(event_type_4_bits & 0xfff0));
-  return (event_type_4_bits << 12) | time_delta_12_bits;
-}
-
-bool EventTimestampLessThan(const RtcpReceiverEventLogMessage& lhs,
-                            const RtcpReceiverEventLogMessage& rhs) {
-  return lhs.event_timestamp < rhs.event_timestamp;
-}
-
-void AddReceiverLog(
-    const RtcpReceiverLogMessage& redundancy_receiver_log_message,
-    RtcpReceiverLogMessage* receiver_log_message,
-    size_t* remaining_space,
-    size_t* number_of_frames,
-    size_t* total_number_of_messages_to_send) {
-  RtcpReceiverLogMessage::const_iterator it =
-      redundancy_receiver_log_message.begin();
-  while (it != redundancy_receiver_log_message.end() &&
-         *remaining_space >=
-             kRtcpReceiverFrameLogSize + kRtcpReceiverEventLogSize) {
-    receiver_log_message->push_front(*it);
-    size_t num_event_logs = (*remaining_space - kRtcpReceiverFrameLogSize) /
-                            kRtcpReceiverEventLogSize;
-    RtcpReceiverEventLogMessages& event_log_messages =
-        receiver_log_message->front().event_log_messages_;
-    if (num_event_logs < event_log_messages.size())
-      event_log_messages.resize(num_event_logs);
-
-    *remaining_space -= kRtcpReceiverFrameLogSize +
-                        event_log_messages.size() * kRtcpReceiverEventLogSize;
-    ++*number_of_frames;
-    *total_number_of_messages_to_send += event_log_messages.size();
-    ++it;
-  }
-}
-
-// A class to build a string representing the NACK list in Cast message.
-//
-// The string will look like "23:3-6 25:1,5-6", meaning packets 3 to 6 in frame
-// 23 are being NACK'ed (i.e. they are missing from the receiver's point of
-// view) and packets 1, 5 and 6 are missing in frame 25. A frame that is
-// completely missing will show as "26:65535".
-class NackStringBuilder {
- public:
-  NackStringBuilder()
-      : frame_count_(0),
-        packet_count_(0),
-        last_frame_id_(-1),
-        last_packet_id_(-1),
-        contiguous_sequence_(false) {}
-  ~NackStringBuilder() {}
-
-  bool Empty() const { return frame_count_ == 0; }
-
-  void PushFrame(int frame_id) {
-    DCHECK_GE(frame_id, 0);
-    if (frame_count_ > 0) {
-      if (frame_id == last_frame_id_) {
-        return;
-      }
-      if (contiguous_sequence_) {
-        stream_ << "-" << last_packet_id_;
-      }
-      stream_ << ", ";
-    }
-    stream_ << frame_id;
-    last_frame_id_ = frame_id;
-    packet_count_ = 0;
-    contiguous_sequence_ = false;
-    ++frame_count_;
-  }
-
-  void PushPacket(int packet_id) {
-    DCHECK_GE(last_frame_id_, 0);
-    DCHECK_GE(packet_id, 0);
-    if (packet_count_ == 0) {
-      stream_ << ":" << packet_id;
-    } else if (packet_id == last_packet_id_ + 1) {
-      contiguous_sequence_ = true;
-    } else {
-      if (contiguous_sequence_) {
-        stream_ << "-" << last_packet_id_;
-        contiguous_sequence_ = false;
-      }
-      stream_ << "," << packet_id;
-    }
-    ++packet_count_;
-    last_packet_id_ = packet_id;
-  }
-
-  std::string GetString() {
-    if (contiguous_sequence_) {
-      stream_ << "-" << last_packet_id_;
-      contiguous_sequence_ = false;
-    }
-    return stream_.str();
-  }
-
- private:
-  std::ostringstream stream_;
-  int frame_count_;
-  int packet_count_;
-  int last_frame_id_;
-  int last_packet_id_;
-  bool contiguous_sequence_;
-};
-}  // namespace
-
-RtcpSender::RtcpSender(PacedPacketSender* outgoing_transport,
-                       uint32 sending_ssrc)
-    : ssrc_(sending_ssrc),
-      transport_(outgoing_transport) {
-}
-
-RtcpSender::~RtcpSender() {}
-
-void RtcpSender::SendRtcpFromRtpReceiver(
-    const RtcpReportBlock* report_block,
-    const RtcpReceiverReferenceTimeReport* rrtr,
-    const RtcpCastMessage* cast_message,
-    const ReceiverRtcpEventSubscriber::RtcpEventMultiMap* rtcp_events,
-    base::TimeDelta target_delay) {
-  PacketRef packet(new base::RefCountedData<Packet>);
-  packet->data.reserve(kMaxIpPacketSize);
-  if (report_block)
-    BuildRR(report_block, &packet->data);
-  if (rrtr)
-    BuildRrtr(rrtr, &packet->data);
-  if (cast_message)
-    BuildCast(cast_message, target_delay, &packet->data);
-  if (rtcp_events)
-    BuildReceiverLog(*rtcp_events, &packet->data);
-
-  if (packet->data.empty()) {
-    NOTREACHED() << "Empty packet.";
-    return;  // Sanity don't send empty packets.
-  }
-
-  transport_->SendRtcpPacket(ssrc_, packet);
-}
-
-void RtcpSender::SendRtcpFromRtpSender(
-    const RtcpSenderInfo& sender_info) {
-  PacketRef packet(new base::RefCountedData<Packet>);
-  packet->data.reserve(kMaxIpPacketSize);
-  BuildSR(sender_info, &packet->data);
-
-  if (packet->data.empty()) {
-    NOTREACHED() << "Empty packet.";
-    return;  // Sanity - don't send empty packets.
-  }
-
-  transport_->SendRtcpPacket(ssrc_, packet);
-}
-
-void RtcpSender::BuildRR(const RtcpReportBlock* report_block,
-                         Packet* packet) const {
-  size_t start_size = packet->size();
-  DCHECK_LT(start_size + 32, kMaxIpPacketSize) << "Not enough buffer space";
-  if (start_size + 32 > kMaxIpPacketSize)
-    return;
-
-  uint16 number_of_rows = (report_block) ? 7 : 1;
-  packet->resize(start_size + 8);
-
-  base::BigEndianWriter big_endian_writer(
-      reinterpret_cast<char*>(&((*packet)[start_size])), 8);
-  big_endian_writer.WriteU8(0x80 + (report_block ? 1 : 0));
-  big_endian_writer.WriteU8(kPacketTypeReceiverReport);
-  big_endian_writer.WriteU16(number_of_rows);
-  big_endian_writer.WriteU32(ssrc_);
-
-  if (report_block) {
-    AddReportBlocks(*report_block, packet);  // Adds 24 bytes.
-  }
-}
-
-void RtcpSender::AddReportBlocks(const RtcpReportBlock& report_block,
-                                 Packet* packet) const {
-  size_t start_size = packet->size();
-  DCHECK_LT(start_size + 24, kMaxIpPacketSize) << "Not enough buffer space";
-  if (start_size + 24 > kMaxIpPacketSize)
-    return;
-
-  packet->resize(start_size + 24);
-
-  base::BigEndianWriter big_endian_writer(
-      reinterpret_cast<char*>(&((*packet)[start_size])), 24);
-  big_endian_writer.WriteU32(report_block.media_ssrc);
-  big_endian_writer.WriteU8(report_block.fraction_lost);
-  big_endian_writer.WriteU8(report_block.cumulative_lost >> 16);
-  big_endian_writer.WriteU8(report_block.cumulative_lost >> 8);
-  big_endian_writer.WriteU8(report_block.cumulative_lost);
-
-  // Extended highest seq_no, contain the highest sequence number received.
-  big_endian_writer.WriteU32(report_block.extended_high_sequence_number);
-  big_endian_writer.WriteU32(report_block.jitter);
-
-  // Last SR timestamp; our NTP time when we received the last report.
-  // This is the value that we read from the send report packet not when we
-  // received it.
-  big_endian_writer.WriteU32(report_block.last_sr);
-
-  // Delay since last received report, time since we received the report.
-  big_endian_writer.WriteU32(report_block.delay_since_last_sr);
-}
-
-void RtcpSender::BuildRrtr(const RtcpReceiverReferenceTimeReport* rrtr,
-                           Packet* packet) const {
-  size_t start_size = packet->size();
-  DCHECK_LT(start_size + 20, kMaxIpPacketSize) << "Not enough buffer space";
-  if (start_size + 20 > kMaxIpPacketSize)
-    return;
-
-  packet->resize(start_size + 20);
-
-  base::BigEndianWriter big_endian_writer(
-      reinterpret_cast<char*>(&((*packet)[start_size])), 20);
-
-  big_endian_writer.WriteU8(0x80);
-  big_endian_writer.WriteU8(kPacketTypeXr);
-  big_endian_writer.WriteU16(4);      // Length.
-  big_endian_writer.WriteU32(ssrc_);  // Add our own SSRC.
-  big_endian_writer.WriteU8(4);       // Add block type.
-  big_endian_writer.WriteU8(0);       // Add reserved.
-  big_endian_writer.WriteU16(2);      // Block length.
-
-  // Add the media (received RTP) SSRC.
-  big_endian_writer.WriteU32(rrtr->ntp_seconds);
-  big_endian_writer.WriteU32(rrtr->ntp_fraction);
-}
-
-void RtcpSender::BuildCast(const RtcpCastMessage* cast,
-                           base::TimeDelta target_delay,
-                           Packet* packet) const {
-  size_t start_size = packet->size();
-  DCHECK_LT(start_size + 20, kMaxIpPacketSize) << "Not enough buffer space";
-  if (start_size + 20 > kMaxIpPacketSize)
-    return;
-
-  packet->resize(start_size + 20);
-
-  base::BigEndianWriter big_endian_writer(
-      reinterpret_cast<char*>(&((*packet)[start_size])), 20);
-  uint8 FMT = 15;  // Application layer feedback.
-  big_endian_writer.WriteU8(0x80 + FMT);
-  big_endian_writer.WriteU8(kPacketTypePayloadSpecific);
-  big_endian_writer.WriteU8(0);
-  size_t cast_size_pos = start_size + 3;  // Save length position.
-  big_endian_writer.WriteU8(4);
-  big_endian_writer.WriteU32(ssrc_);              // Add our own SSRC.
-  big_endian_writer.WriteU32(cast->media_ssrc);  // Remote SSRC.
-  big_endian_writer.WriteU32(kCast);
-  big_endian_writer.WriteU8(static_cast<uint8>(cast->ack_frame_id));
-  size_t cast_loss_field_pos = start_size + 17;  // Save loss field position.
-  big_endian_writer.WriteU8(0);  // Overwritten with number_of_loss_fields.
-  DCHECK_LE(target_delay.InMilliseconds(),
-            std::numeric_limits<uint16_t>::max());
-  big_endian_writer.WriteU16(target_delay.InMilliseconds());
-
-  size_t number_of_loss_fields = 0;
-  size_t max_number_of_loss_fields = std::min<size_t>(
-      kRtcpMaxCastLossFields, (kMaxIpPacketSize - packet->size()) / 4);
-
-  MissingFramesAndPacketsMap::const_iterator frame_it =
-      cast->missing_frames_and_packets.begin();
-
-  NackStringBuilder nack_string_builder;
-  for (; frame_it != cast->missing_frames_and_packets.end() &&
-             number_of_loss_fields < max_number_of_loss_fields;
-       ++frame_it) {
-    nack_string_builder.PushFrame(frame_it->first);
-    // Iterate through all frames with missing packets.
-    if (frame_it->second.empty()) {
-      // Special case all packets in a frame is missing.
-      start_size = packet->size();
-      packet->resize(start_size + 4);
-      base::BigEndianWriter big_endian_nack_writer(
-          reinterpret_cast<char*>(&((*packet)[start_size])), 4);
-      big_endian_nack_writer.WriteU8(static_cast<uint8>(frame_it->first));
-      big_endian_nack_writer.WriteU16(kRtcpCastAllPacketsLost);
-      big_endian_nack_writer.WriteU8(0);
-      nack_string_builder.PushPacket(kRtcpCastAllPacketsLost);
-      ++number_of_loss_fields;
-    } else {
-      PacketIdSet::const_iterator packet_it = frame_it->second.begin();
-      while (packet_it != frame_it->second.end()) {
-        uint16 packet_id = *packet_it;
-
-        start_size = packet->size();
-        packet->resize(start_size + 4);
-        base::BigEndianWriter big_endian_nack_writer(
-            reinterpret_cast<char*>(&((*packet)[start_size])), 4);
-
-        // Write frame and packet id to buffer before calculating bitmask.
-        big_endian_nack_writer.WriteU8(static_cast<uint8>(frame_it->first));
-        big_endian_nack_writer.WriteU16(packet_id);
-        nack_string_builder.PushPacket(packet_id);
-
-        uint8 bitmask = 0;
-        ++packet_it;
-        while (packet_it != frame_it->second.end()) {
-          int shift = static_cast<uint8>(*packet_it - packet_id) - 1;
-          if (shift >= 0 && shift <= 7) {
-            nack_string_builder.PushPacket(*packet_it);
-            bitmask |= (1 << shift);
-            ++packet_it;
-          } else {
-            break;
-          }
-        }
-        big_endian_nack_writer.WriteU8(bitmask);
-        ++number_of_loss_fields;
-      }
-    }
-  }
-  VLOG_IF(1, !nack_string_builder.Empty())
-      << "SSRC: " << cast->media_ssrc
-      << ", ACK: " << cast->ack_frame_id
-      << ", NACK: " << nack_string_builder.GetString();
-  DCHECK_LE(number_of_loss_fields, kRtcpMaxCastLossFields);
-  (*packet)[cast_size_pos] = static_cast<uint8>(4 + number_of_loss_fields);
-  (*packet)[cast_loss_field_pos] = static_cast<uint8>(number_of_loss_fields);
-}
-
-void RtcpSender::BuildSR(const RtcpSenderInfo& sender_info,
-                         Packet* packet) const {
-  // Sender report.
-  size_t start_size = packet->size();
-  if (start_size + 52 > kMaxIpPacketSize) {
-    DLOG(FATAL) << "Not enough buffer space";
-    return;
-  }
-
-  uint16 number_of_rows = 6;
-  packet->resize(start_size + 28);
-
-  base::BigEndianWriter big_endian_writer(
-      reinterpret_cast<char*>(&((*packet)[start_size])), 28);
-  big_endian_writer.WriteU8(0x80);
-  big_endian_writer.WriteU8(kPacketTypeSenderReport);
-  big_endian_writer.WriteU16(number_of_rows);
-  big_endian_writer.WriteU32(ssrc_);
-  big_endian_writer.WriteU32(sender_info.ntp_seconds);
-  big_endian_writer.WriteU32(sender_info.ntp_fraction);
-  big_endian_writer.WriteU32(sender_info.rtp_timestamp);
-  big_endian_writer.WriteU32(sender_info.send_packet_count);
-  big_endian_writer.WriteU32(static_cast<uint32>(sender_info.send_octet_count));
-  return;
-}
-
-/*
-   0                   1                   2                   3
-   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
-  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-  |V=2|P|reserved |   PT=XR=207   |             length            |
-  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-  |                              SSRC                             |
-  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-  |     BT=5      |   reserved    |         block length          |
-  +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
-  |                 SSRC1 (SSRC of first receiver)               | sub-
-  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ block
-  |                         last RR (LRR)                         |   1
-  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-  |                   delay since last RR (DLRR)                  |
-  +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
-*/
-void RtcpSender::BuildDlrrRb(const RtcpDlrrReportBlock& dlrr,
-                             Packet* packet) const {
-  size_t start_size = packet->size();
-  if (start_size + 24 > kMaxIpPacketSize) {
-    DLOG(FATAL) << "Not enough buffer space";
-    return;
-  }
-
-  packet->resize(start_size + 24);
-
-  base::BigEndianWriter big_endian_writer(
-      reinterpret_cast<char*>(&((*packet)[start_size])), 24);
-  big_endian_writer.WriteU8(0x80);
-  big_endian_writer.WriteU8(kPacketTypeXr);
-  big_endian_writer.WriteU16(5);  // Length.
-  big_endian_writer.WriteU32(ssrc_);  // Add our own SSRC.
-  big_endian_writer.WriteU8(5);  // Add block type.
-  big_endian_writer.WriteU8(0);  // Add reserved.
-  big_endian_writer.WriteU16(3);  // Block length.
-  big_endian_writer.WriteU32(ssrc_);  // Add the media (received RTP) SSRC.
-  big_endian_writer.WriteU32(dlrr.last_rr);
-  big_endian_writer.WriteU32(dlrr.delay_since_last_rr);
-  return;
-}
-
-void RtcpSender::BuildReceiverLog(
-    const ReceiverRtcpEventSubscriber::RtcpEventMultiMap& rtcp_events,
-    Packet* packet) {
-  const size_t packet_start_size = packet->size();
-  size_t number_of_frames = 0;
-  size_t total_number_of_messages_to_send = 0;
-  size_t rtcp_log_size = 0;
-  RtcpReceiverLogMessage receiver_log_message;
-
-  if (!BuildRtcpReceiverLogMessage(rtcp_events,
-                                   packet_start_size,
-                                   &receiver_log_message,
-                                   &number_of_frames,
-                                   &total_number_of_messages_to_send,
-                                   &rtcp_log_size)) {
-    return;
-  }
-  packet->resize(packet_start_size + rtcp_log_size);
-
-  base::BigEndianWriter big_endian_writer(
-      reinterpret_cast<char*>(&((*packet)[packet_start_size])), rtcp_log_size);
-  big_endian_writer.WriteU8(0x80 + kReceiverLogSubtype);
-  big_endian_writer.WriteU8(kPacketTypeApplicationDefined);
-  big_endian_writer.WriteU16(static_cast<uint16>(
-      2 + 2 * number_of_frames + total_number_of_messages_to_send));
-  big_endian_writer.WriteU32(ssrc_);  // Add our own SSRC.
-  big_endian_writer.WriteU32(kCast);
-
-  while (!receiver_log_message.empty() &&
-         total_number_of_messages_to_send > 0) {
-    RtcpReceiverFrameLogMessage& frame_log_messages(
-        receiver_log_message.front());
-
-    // Add our frame header.
-    big_endian_writer.WriteU32(frame_log_messages.rtp_timestamp_);
-    size_t messages_in_frame = frame_log_messages.event_log_messages_.size();
-    if (messages_in_frame > total_number_of_messages_to_send) {
-      // We are running out of space.
-      messages_in_frame = total_number_of_messages_to_send;
-    }
-    // Keep track of how many messages we have left to send.
-    total_number_of_messages_to_send -= messages_in_frame;
-
-    // On the wire format is number of messages - 1.
-    big_endian_writer.WriteU8(static_cast<uint8>(messages_in_frame - 1));
-
-    base::TimeTicks event_timestamp_base =
-        frame_log_messages.event_log_messages_.front().event_timestamp;
-    uint32 base_timestamp_ms =
-        (event_timestamp_base - base::TimeTicks()).InMilliseconds();
-    big_endian_writer.WriteU8(static_cast<uint8>(base_timestamp_ms >> 16));
-    big_endian_writer.WriteU8(static_cast<uint8>(base_timestamp_ms >> 8));
-    big_endian_writer.WriteU8(static_cast<uint8>(base_timestamp_ms));
-
-    while (!frame_log_messages.event_log_messages_.empty() &&
-           messages_in_frame > 0) {
-      const RtcpReceiverEventLogMessage& event_message =
-          frame_log_messages.event_log_messages_.front();
-      uint16 event_type_and_timestamp_delta =
-          MergeEventTypeAndTimestampForWireFormat(
-              event_message.type,
-              event_message.event_timestamp - event_timestamp_base);
-      switch (event_message.type) {
-        case FRAME_ACK_SENT:
-        case FRAME_PLAYOUT:
-        case FRAME_DECODED:
-          big_endian_writer.WriteU16(
-              static_cast<uint16>(event_message.delay_delta.InMilliseconds()));
-          big_endian_writer.WriteU16(event_type_and_timestamp_delta);
-          break;
-        case PACKET_RECEIVED:
-          big_endian_writer.WriteU16(event_message.packet_id);
-          big_endian_writer.WriteU16(event_type_and_timestamp_delta);
-          break;
-        default:
-          NOTREACHED();
-      }
-      messages_in_frame--;
-      frame_log_messages.event_log_messages_.pop_front();
-    }
-    if (frame_log_messages.event_log_messages_.empty()) {
-      // We sent all messages on this frame; pop the frame header.
-      receiver_log_message.pop_front();
-    }
-  }
-  DCHECK_EQ(total_number_of_messages_to_send, 0u);
-}
-
-bool RtcpSender::BuildRtcpReceiverLogMessage(
-    const ReceiverRtcpEventSubscriber::RtcpEventMultiMap& rtcp_events,
-    size_t start_size,
-    RtcpReceiverLogMessage* receiver_log_message,
-    size_t* number_of_frames,
-    size_t* total_number_of_messages_to_send,
-    size_t* rtcp_log_size) {
-  size_t remaining_space =
-      std::min(kMaxReceiverLogBytes, kMaxIpPacketSize - start_size);
-  if (remaining_space < kRtcpCastLogHeaderSize + kRtcpReceiverFrameLogSize +
-                            kRtcpReceiverEventLogSize) {
-    return false;
-  }
-
-  // We use this to do event timestamp sorting and truncating for events of
-  // a single frame.
-  std::vector<RtcpReceiverEventLogMessage> sorted_log_messages;
-
-  // Account for the RTCP header for an application-defined packet.
-  remaining_space -= kRtcpCastLogHeaderSize;
-
-  ReceiverRtcpEventSubscriber::RtcpEventMultiMap::const_reverse_iterator rit =
-      rtcp_events.rbegin();
-
-  while (rit != rtcp_events.rend() &&
-         remaining_space >=
-             kRtcpReceiverFrameLogSize + kRtcpReceiverEventLogSize) {
-    const RtpTimestamp rtp_timestamp = rit->first;
-    RtcpReceiverFrameLogMessage frame_log(rtp_timestamp);
-    remaining_space -= kRtcpReceiverFrameLogSize;
-    ++*number_of_frames;
-
-    // Get all events of a single frame.
-    sorted_log_messages.clear();
-    do {
-      RtcpReceiverEventLogMessage event_log_message;
-      event_log_message.type = rit->second.type;
-      event_log_message.event_timestamp = rit->second.timestamp;
-      event_log_message.delay_delta = rit->second.delay_delta;
-      event_log_message.packet_id = rit->second.packet_id;
-      sorted_log_messages.push_back(event_log_message);
-      ++rit;
-    } while (rit != rtcp_events.rend() && rit->first == rtp_timestamp);
-
-    std::sort(sorted_log_messages.begin(),
-              sorted_log_messages.end(),
-              &EventTimestampLessThan);
-
-    // From |sorted_log_messages|, only take events that are no greater than
-    // |kMaxWireFormatTimeDeltaMs| seconds away from the latest event. Events
-    // older than that cannot be encoded over the wire.
-    std::vector<RtcpReceiverEventLogMessage>::reverse_iterator sorted_rit =
-        sorted_log_messages.rbegin();
-    base::TimeTicks first_event_timestamp = sorted_rit->event_timestamp;
-    size_t events_in_frame = 0;
-    while (sorted_rit != sorted_log_messages.rend() &&
-           events_in_frame < kRtcpMaxReceiverLogMessages &&
-           remaining_space >= kRtcpReceiverEventLogSize) {
-      base::TimeDelta delta(first_event_timestamp -
-                            sorted_rit->event_timestamp);
-      if (delta.InMilliseconds() > kMaxWireFormatTimeDeltaMs)
-        break;
-      frame_log.event_log_messages_.push_front(*sorted_rit);
-      ++events_in_frame;
-      ++*total_number_of_messages_to_send;
-      remaining_space -= kRtcpReceiverEventLogSize;
-      ++sorted_rit;
-    }
-
-    receiver_log_message->push_front(frame_log);
-  }
-
-  rtcp_events_history_.push_front(*receiver_log_message);
-
-  // We don't try to match RTP timestamps of redundancy frame logs with those
-  // from the newest set (which would save the space of an extra RTP timestamp
-  // over the wire). Unless the redundancy frame logs are very recent, it's
-  // unlikely there will be a match anyway.
-  if (rtcp_events_history_.size() > kFirstRedundancyOffset) {
-    // Add first redundnacy messages, if enough space remaining
-    AddReceiverLog(rtcp_events_history_[kFirstRedundancyOffset],
-                   receiver_log_message,
-                   &remaining_space,
-                   number_of_frames,
-                   total_number_of_messages_to_send);
-  }
-
-  if (rtcp_events_history_.size() > kSecondRedundancyOffset) {
-    // Add second redundancy messages, if enough space remaining
-    AddReceiverLog(rtcp_events_history_[kSecondRedundancyOffset],
-                   receiver_log_message,
-                   &remaining_space,
-                   number_of_frames,
-                   total_number_of_messages_to_send);
-  }
-
-  if (rtcp_events_history_.size() > kReceiveLogMessageHistorySize) {
-    rtcp_events_history_.pop_back();
-  }
-
-  DCHECK_LE(rtcp_events_history_.size(), kReceiveLogMessageHistorySize);
-
-  *rtcp_log_size =
-      kRtcpCastLogHeaderSize + *number_of_frames * kRtcpReceiverFrameLogSize +
-      *total_number_of_messages_to_send * kRtcpReceiverEventLogSize;
-  DCHECK_GE(kMaxIpPacketSize, start_size + *rtcp_log_size)
-      << "Not enough buffer space.";
-
-  VLOG(3) << "number of frames: " << *number_of_frames;
-  VLOG(3) << "total messages to send: " << *total_number_of_messages_to_send;
-  VLOG(3) << "rtcp log size: " << *rtcp_log_size;
-  return *number_of_frames > 0;
-}
-
-}  // namespace cast
-}  // namespace media