Add FlexfecSender.

webrtc/modules/rtp_rtcp/source/ulpfec_generator.cc

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 76 matching lines @@
 
 uint8_t* RedPacket::data() const {
   return data_.get();
 }
 
 size_t RedPacket::length() const {
   return length_;
 }
 
 UlpfecGenerator::UlpfecGenerator()
-    : fec_(ForwardErrorCorrection::CreateUlpfec()),
+    : UlpfecGenerator(ForwardErrorCorrection::CreateUlpfec()) {}
+
+UlpfecGenerator::UlpfecGenerator(std::unique_ptr<ForwardErrorCorrection> fec)
+    : fec_(std::move(fec)),
       num_protected_frames_(0),
       min_num_media_packets_(1) {
   memset(&params_, 0, sizeof(params_));
   memset(&new_params_, 0, sizeof(new_params_));
 }
 
 UlpfecGenerator::~UlpfecGenerator() = default;
 
 std::unique_ptr<RedPacket> UlpfecGenerator::BuildRedPacket(
     const uint8_t* data_buffer,
@@ skipping 25 matching lines @@
 int UlpfecGenerator::AddRtpPacketAndGenerateFec(const uint8_t* data_buffer,
                                                 size_t payload_length,
                                                 size_t rtp_header_length) {
   RTC_DCHECK(generated_fec_packets_.empty());
   if (media_packets_.empty()) {
     params_ = new_params_;
   }
   bool complete_frame = false;
   const bool marker_bit = (data_buffer[1] & kRtpMarkerBitMask) ? true : false;
   if (media_packets_.size() < kUlpfecMaxMediaPackets) {
-    // Generic FEC can only protect up to |kUlpfecMaxMediaPackets| packets.
+    // Our packet masks can only protect up to |kUlpfecMaxMediaPackets| packets.
     std::unique_ptr<ForwardErrorCorrection::Packet> packet(
         new ForwardErrorCorrection::Packet());
     packet->length = payload_length + rtp_header_length;
     memcpy(packet->data, data_buffer, packet->length);
     media_packets_.push_back(std::move(packet));
   }
   if (marker_bit) {
     ++num_protected_frames_;
     complete_frame = true;
   }
@@ skipping 85 matching lines @@
   return (num_fec_packets << 8) / media_packets_.size();
 }
 
 void UlpfecGenerator::ResetState() {
   media_packets_.clear();
   generated_fec_packets_.clear();
   num_protected_frames_ = 0;
 }
 
 }  // namespace webrtc