Remove time constraint on first retransmit of a packet.

webrtc/modules/rtp_rtcp/source/rtp_packet_history.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.
  */
 
 #include "webrtc/modules/rtp_rtcp/source/rtp_packet_history.h"
 
 #include <assert.h>
 #include <stdlib.h>
 #include <string.h>   // memset
 #include <limits>
 #include <set>
 
+#include "webrtc/base/checks.h"
 #include "webrtc/modules/rtp_rtcp/source/rtp_utility.h"
 #include "webrtc/system_wrappers/interface/critical_section_wrapper.h"
 #include "webrtc/system_wrappers/interface/logging.h"
 
 namespace webrtc {
 
 static const int kMinPacketRequestBytes = 50;
 
 RTPPacketHistory::RTPPacketHistory(Clock* clock)
     : clock_(clock),
@@ skipping 82 matching lines @@
   // TODO(sprang): Overhaul this class and get rid of this copy step.
   //               (Finally introduce the RtpPacket class?)
   memcpy(stored_packets_[prev_index_].data, packet, packet_length);
   stored_packets_[prev_index_].length = packet_length;
 
   stored_packets_[prev_index_].sequence_number = seq_num;
   stored_packets_[prev_index_].time_ms =
       (capture_time_ms > 0) ? capture_time_ms : clock_->TimeInMilliseconds();
   stored_packets_[prev_index_].send_time = 0;  // Packet not sent.
   stored_packets_[prev_index_].storage_type = type;
+  stored_packets_[prev_index_].has_been_retransmitted = false;
 
   ++prev_index_;
   if (prev_index_ >= stored_packets_.size()) {
     prev_index_ = 0;
   }
   return 0;
 }
 
 bool RTPPacketHistory::HasRTPPacket(uint16_t sequence_number) const {
   CriticalSectionScoped cs(critsect_.get());
@@ skipping 35 matching lines @@
   return true;
 }
 
 bool RTPPacketHistory::GetPacketAndSetSendTime(uint16_t sequence_number,
                                                int64_t min_elapsed_time_ms,
                                                bool retransmit,
                                                uint8_t* packet,
                                                size_t* packet_length,
                                                int64_t* stored_time_ms) {
   CriticalSectionScoped cs(critsect_.get());
-  assert(*packet_length >= IP_PACKET_SIZE);
-  if (!store_) {
+  RTC_CHECK_GE(*packet_length, static_cast<size_t>(IP_PACKET_SIZE));
+  if (!store_)
     return false;
-  }
 
   int32_t index = 0;
   bool found = FindSeqNum(sequence_number, &index);
   if (!found) {
     LOG(LS_WARNING) << "No match for getting seqNum " << sequence_number;
     return false;
   }
 
   size_t length = stored_packets_[index].length;
   assert(length <= IP_PACKET_SIZE);
   if (length == 0) {
     LOG(LS_WARNING) << "No match for getting seqNum " << sequence_number
                     << ", len " << length;
     return false;
   }
 
-  // Verify elapsed time since last retrieve.
+  // Verify elapsed time since last retrieve, but only for retransmissions and
+  // always send packet upon first retransmission request.
   int64_t now = clock_->TimeInMilliseconds();
-  if (min_elapsed_time_ms > 0 &&
+  if (min_elapsed_time_ms > 0 && retransmit &&
+      stored_packets_[index].has_been_retransmitted &&
       ((now - stored_packets_[index].send_time) < min_elapsed_time_ms)) {
     return false;
   }
 
-  if (retransmit && stored_packets_[index].storage_type == kDontRetransmit) {
-    // No bytes copied since this packet shouldn't be retransmitted or is
-    // of zero size.
-    return false;
+  if (retransmit) {
+    if (stored_packets_[index].storage_type == kDontRetransmit) {
+      // No bytes copied since this packet shouldn't be retransmitted or is
+      // of zero size.
+      return false;
+    }
+    stored_packets_[index].has_been_retransmitted = true;
   }
   stored_packets_[index].send_time = clock_->TimeInMilliseconds();
   GetPacket(index, packet, packet_length, stored_time_ms);
   return true;
 }
 
 void RTPPacketHistory::GetPacket(int index,
                                  uint8_t* packet,
                                  size_t* packet_length,
                                  int64_t* stored_time_ms) const {
@@ skipping 67 matching lines @@
       min_diff = diff;
       best_index = static_cast<int>(i);
     }
   }
   return best_index;
 }
 
 RTPPacketHistory::StoredPacket::StoredPacket() {}
 
 }  // namespace webrtc