Re-enable RestartingSendStreamPreservesRtpState.

webrtc/video/end_to_end_tests.cc

Index: webrtc/video/end_to_end_tests.cc
diff --git a/webrtc/video/end_to_end_tests.cc b/webrtc/video/end_to_end_tests.cc
index 6201e92220f0291085451ee6bb46bdb98ae8d9fd..a25d1824e1bc360ac36f87015109be059eb68dbb 100644
--- a/webrtc/video/end_to_end_tests.cc
+++ b/webrtc/video/end_to_end_tests.cc
@@ -8,6 +8,7 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 #include <algorithm>
+#include <list>
 #include <map>
 #include <sstream>
 #include <string>
@@ -2935,7 +2936,6 @@ TEST_F(EndToEndTest, DISABLED_RedundantPayloadsTransmittedOnAllSsrcs) {
 }
 
 void EndToEndTest::TestRtpStatePreservation(bool use_rtx) {
-  static const uint32_t kMaxSequenceNumberGap = 100;
   static const uint64_t kMaxTimestampGap = kDefaultTimeoutMs * 90;
   class RtpSequenceObserver : public test::RtpRtcpObserver {
    public:
@@ -2968,25 +2968,41 @@ void EndToEndTest::TestRtpStatePreservation(bool use_rtx) {
       EXPECT_TRUE(configured_ssrcs_[ssrc])
           << "Received SSRC that wasn't configured: " << ssrc;
 
-      std::map<uint32_t, uint16_t>::iterator it =
-          last_observed_sequence_number_.find(header.ssrc);
-      if (it == last_observed_sequence_number_.end()) {
-        last_observed_sequence_number_[ssrc] = sequence_number;
-        last_observed_timestamp_[ssrc] = timestamp;
+      static const uint16_t kMaxSequenceNumberGap = 100;
+      std::list<uint16_t>& seq_numbers = last_observed_seq_numbers_[ssrc];

[pbos-webrtc, 2016/02/03 13:03:27]

pointer instead of reference here please.

[danilchap, 2016/02/03 14:04:48]

Done.

+      if (seq_numbers.empty()) {
+        seq_numbers.push_back(sequence_number);
       } else {
+        // We shouldn't get replays of previous sequence numbers.
+        for (uint16_t observed : seq_numbers) {
+          EXPECT_NE(observed, sequence_number)
+              << "Received sequence number " << sequence_number
+              << " for SSRC " << ssrc << " 2nd time.";
+        }
         // Verify sequence numbers are reasonably close.

[pbos-webrtc, 2016/02/03 13:03:27]

There should be some timediff function that does this abs_diff for you already.

[danilchap, 2016/02/03 14:04:48]

Failed to find it. Thank you for pointing where it is.
instead of IsNewer used Unwrapper since that fits better how seq numbers are
used in this test.
The case where 1st packet starts with 2^16-1 and comes before packet with seq_no
0 is silently ignored because maximum starting seq_no is 2^15-1.

-        uint32_t extended_sequence_number = sequence_number;
-        // Check for roll-over.
-        if (sequence_number < last_observed_sequence_number_[ssrc])
-          extended_sequence_number += 0xFFFFu + 1;
-        EXPECT_LE(
-            extended_sequence_number - last_observed_sequence_number_[ssrc],
-            kMaxSequenceNumberGap)
-            << "Gap in sequence numbers ("
-            << last_observed_sequence_number_[ssrc] << " -> " << sequence_number
-            << ") too large for SSRC: " << ssrc << ".";
-        last_observed_sequence_number_[ssrc] = sequence_number;
+        uint16_t latest_observed = seq_numbers.back();
+        uint16_t diff = sequence_number - latest_observed;
+        uint16_t abs_diff;
+        if (diff < 0x8000) {  // Positive difference.
+          abs_diff = diff;
+        } else {  // Negative difference.
+          abs_diff = (0xffff - diff) + 1;
+        }
+        EXPECT_LE(abs_diff, kMaxSequenceNumberGap)
+          << "Gap in sequence numbers ("
+          << latest_observed << " -> " << sequence_number
+          << ") too large for SSRC: " << ssrc << ".";
+        seq_numbers.push_back(sequence_number);
+        if (seq_numbers.size() >= kMaxSequenceNumberGap) {
+          seq_numbers.pop_front();
+        }
+      }
 
+      std::map<uint32_t, uint32_t>::iterator it =
+          last_observed_timestamp_.find(ssrc);
+      if (it == last_observed_timestamp_.end()) {
+        last_observed_timestamp_[ssrc] = timestamp;
+      } else {
         // TODO(pbos): Remove this check if we ever have monotonically
         // increasing timestamps. Right now padding packets add a delta which
         // can cause reordering between padding packets and regular packets,
@@ -3016,7 +3032,7 @@ void EndToEndTest::TestRtpStatePreservation(bool use_rtx) {
       return SEND_PACKET;
     }
 
-    std::map<uint32_t, uint16_t> last_observed_sequence_number_;
+    std::map<uint32_t, std::list<uint16_t>> last_observed_seq_numbers_;
     std::map<uint32_t, uint32_t> last_observed_timestamp_;
     std::map<uint32_t, bool> configured_ssrcs_;
 
@@ -3115,7 +3131,7 @@ void EndToEndTest::TestRtpStatePreservation(bool use_rtx) {
   DestroyStreams();
 }
 
-TEST_F(EndToEndTest, DISABLED_RestartingSendStreamPreservesRtpState) {
+TEST_F(EndToEndTest, RestartingSendStreamPreservesRtpState) {
   TestRtpStatePreservation(false);
 }