Fix bug in BitrateProber where an old probe added at a high bitrate will stay active indefinit…

webrtc/modules/pacing/bitrate_prober_unittest.cc

 /*
  *  Copyright (c) 2014 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 <limits>
 
 #include "webrtc/modules/pacing/bitrate_prober.h"
 #include "webrtc/test/gtest.h"
 
 namespace webrtc {
 
 TEST(BitrateProberTest, VerifyStatesAndTimeBetweenProbes) {
   BitrateProber prober;
   EXPECT_FALSE(prober.IsProbing());
   int64_t now_ms = 0;
   EXPECT_EQ(-1, prober.TimeUntilNextProbe(now_ms));
 
   const int kTestBitrate1 = 900000;
   const int kTestBitrate2 = 1800000;
   const int kClusterSize = 5;
   const int kProbeSize = 1000;
   const int kMinProbeDurationMs = 15;
 
-  prober.CreateProbeCluster(kTestBitrate1);
-  prober.CreateProbeCluster(kTestBitrate2);
+  prober.CreateProbeCluster(kTestBitrate1, now_ms);
+  prober.CreateProbeCluster(kTestBitrate2, now_ms);
   EXPECT_FALSE(prober.IsProbing());
 
   prober.OnIncomingPacket(kProbeSize);
   EXPECT_TRUE(prober.IsProbing());
   EXPECT_EQ(0, prober.CurrentClusterId());
 
   // First packet should probe as soon as possible.
   EXPECT_EQ(0, prober.TimeUntilNextProbe(now_ms));
 
   for (int i = 0; i < kClusterSize; ++i) {
@@ skipping 29 matching lines @@
   EXPECT_EQ(-1, prober.TimeUntilNextProbe(now_ms));
   EXPECT_FALSE(prober.IsProbing());
 }
 
 TEST(BitrateProberTest, DoesntProbeWithoutRecentPackets) {
   BitrateProber prober;
   EXPECT_FALSE(prober.IsProbing());
   int64_t now_ms = 0;
   EXPECT_EQ(-1, prober.TimeUntilNextProbe(now_ms));
 
-  prober.CreateProbeCluster(900000);
+  prober.CreateProbeCluster(900000, now_ms);
   EXPECT_FALSE(prober.IsProbing());
 
   prober.OnIncomingPacket(1000);
   EXPECT_TRUE(prober.IsProbing());
   EXPECT_EQ(0, prober.TimeUntilNextProbe(now_ms));
   prober.ProbeSent(now_ms, 1000);
   // Let time pass, no large enough packets put into prober.
   now_ms += 6000;
   EXPECT_EQ(-1, prober.TimeUntilNextProbe(now_ms));
   // Insert a large-enough packet after downtime while probing should reset to
@@ skipping 12 matching lines @@
   EXPECT_FALSE(prober.IsProbing());
 
   prober.OnIncomingPacket(100);
   EXPECT_FALSE(prober.IsProbing());
 }
 
 TEST(BitrateProberTest, VerifyProbeSizeOnHighBitrate) {
   BitrateProber prober;
   constexpr unsigned kHighBitrateBps = 10000000;  // 10 Mbps
 
-  prober.CreateProbeCluster(kHighBitrateBps);
+  prober.CreateProbeCluster(kHighBitrateBps, 0);
   // Probe size should ensure a minimum of 1 ms interval.
   EXPECT_GT(prober.RecommendedMinProbeSize(), kHighBitrateBps / 8000);
 }
 
 TEST(BitrateProberTest, MinumumNumberOfProbingPackets) {
   BitrateProber prober;
   // Even when probing at a low bitrate we expect a minimum number
   // of packets to be sent.
   constexpr int kBitrateBps = 100000;  // 100 kbps
   constexpr int kPacketSizeBytes = 1000;
 
-  prober.CreateProbeCluster(kBitrateBps);
+  prober.CreateProbeCluster(kBitrateBps, 0);
   prober.OnIncomingPacket(kPacketSizeBytes);
   for (int i = 0; i < 5; ++i) {
     EXPECT_TRUE(prober.IsProbing());
     prober.ProbeSent(0, kPacketSizeBytes);
   }
 
   EXPECT_FALSE(prober.IsProbing());
 }
 
 TEST(BitrateProberTest, ScaleBytesUsedForProbing) {
   BitrateProber prober;
   constexpr int kBitrateBps = 10000000;  // 10 Mbps
   constexpr int kPacketSizeBytes = 1000;
   constexpr int kExpectedBytesSent = kBitrateBps * 15 / 8000;
 
-  prober.CreateProbeCluster(kBitrateBps);
+  prober.CreateProbeCluster(kBitrateBps, 0);
   prober.OnIncomingPacket(kPacketSizeBytes);
   int bytes_sent = 0;
   while (bytes_sent < kExpectedBytesSent) {
     ASSERT_TRUE(prober.IsProbing());
     prober.ProbeSent(0, kPacketSizeBytes);
     bytes_sent += kPacketSizeBytes;
   }
 
   EXPECT_FALSE(prober.IsProbing());
 }
 
+TEST(BitrateProberTest, ProbeClusterTimeout) {
+  BitrateProber prober;
+  constexpr int kBitrateBps = 300000;  // 300 kbps
+  constexpr int kSmallPacketSize = 20;
+  // Expecting two probe clusters of 5 packets each.
+  constexpr int kExpectedBytesSent = 20 * 2 * 5;
+  constexpr int64_t kTimeoutMs = 5000;
+
+  int64_t now_ms = 0;
+  prober.CreateProbeCluster(kBitrateBps, now_ms);
+  prober.OnIncomingPacket(kSmallPacketSize);
+  EXPECT_FALSE(prober.IsProbing());
+  now_ms += kTimeoutMs;
+  prober.CreateProbeCluster(kBitrateBps / 10, now_ms);
+  prober.OnIncomingPacket(kSmallPacketSize);
+  EXPECT_FALSE(prober.IsProbing());
+  now_ms += 1;
+  prober.CreateProbeCluster(kBitrateBps / 10, now_ms);
+  prober.OnIncomingPacket(kSmallPacketSize);
+  EXPECT_TRUE(prober.IsProbing());
+  int bytes_sent = 0;
+  while (bytes_sent < kExpectedBytesSent) {
+    ASSERT_TRUE(prober.IsProbing());
+    prober.ProbeSent(0, kSmallPacketSize);
+    bytes_sent += kSmallPacketSize;
+  }
+
+  EXPECT_FALSE(prober.IsProbing());
+}
 }  // namespace webrtc