Remove hardcoded kValueSizeBytes values from variable-length header extensions.

webrtc/modules/rtp_rtcp/include/flexfec_sender.h

 /*
  *  Copyright (c) 2016 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.
  */
 
 #ifndef WEBRTC_MODULES_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_
 #define WEBRTC_MODULES_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_
 
 #include <memory>
 #include <vector>
 
+#include "webrtc/base/array_view.h"
 #include "webrtc/base/basictypes.h"
 #include "webrtc/base/random.h"
 #include "webrtc/base/sequenced_task_checker.h"
 #include "webrtc/config.h"
 #include "webrtc/modules/include/module_common_types.h"
 #include "webrtc/modules/rtp_rtcp/include/flexfec_sender.h"
 #include "webrtc/modules/rtp_rtcp/source/rtp_header_extension.h"
 #include "webrtc/modules/rtp_rtcp/source/rtp_packet_to_send.h"
 #include "webrtc/modules/rtp_rtcp/source/ulpfec_generator.h"
 #include "webrtc/system_wrappers/include/clock.h"
 
 namespace webrtc {
 
 class RtpPacketToSend;
 
 // Note that this class is not thread safe, and thus requires external
 // synchronization. Currently, this is done using the lock in PayloadRouter.
 
 class FlexfecSender {
  public:
   FlexfecSender(int payload_type,
                 uint32_t ssrc,
                 uint32_t protected_media_ssrc,
                 const std::vector<RtpExtension>& rtp_header_extensions,
+                rtc::ArrayView<const RtpExtensionSize> extension_sizes,
                 Clock* clock);
   ~FlexfecSender();
 
   uint32_t ssrc() const { return ssrc_; }
 
   // Sets the FEC rate, max frames sent before FEC packets are sent,
   // and what type of generator matrices are used.
   void SetFecParameters(const FecProtectionParams& params);
 
   // Adds a media packet to the internal buffer. When enough media packets
   // have been added, the FEC packets are generated and stored internally.
   // These FEC packets are then obtained by calling GetFecPackets().
   // Returns true if the media packet was successfully added.
   bool AddRtpPacketAndGenerateFec(const RtpPacketToSend& packet);
 
   // Returns true if there are generated FEC packets available.
   bool FecAvailable() const;
 
   // Returns generated FlexFEC packets.
   std::vector<std::unique_ptr<RtpPacketToSend>> GetFecPackets();
 
-  // Returns the overhead, per packet, for FlexFEC.
+  // Returns the overhead, per packet, for FlexFEC. |extension_sizes| is used
+  // to calculate the RTP header extension overhead and it should have an entry

[brandtr, 2017/05/10 14:36:27]

I think this comment is redundant now?

[erikvarga1, 2017/05/10 15:39:31]

Oops, I forgot to remove that. Removed now.

+  // for each extension that a packet might use. If only fixed-length extensions
+  // are used, |extension_sizes| should be the same at each call.
   size_t MaxPacketOverhead() const;
 
  private:
   // Utility.
   Clock* const clock_;
   Random random_;
   int64_t last_generated_packet_ms_;
 
   // Config.
   const int payload_type_;
   const uint32_t timestamp_offset_;
   const uint32_t ssrc_;
   const uint32_t protected_media_ssrc_;
   // Sequence number of next packet to generate.
   uint16_t seq_num_;
 
   // Implementation.
   UlpfecGenerator ulpfec_generator_;
   const RtpHeaderExtensionMap rtp_header_extension_map_;
+  size_t header_extensions_size_;

[brandtr, 2017/05/10 14:36:27]

Can you make this const?

[erikvarga1, 2017/05/10 15:39:31]

Done.

 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_RTP_RTCP_INCLUDE_FLEXFEC_SENDER_H_