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net/quic/congestion_control/rtt_stats.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // A convenience class to store rtt samples and calculate smoothed rtt.
 
 #ifndef NET_QUIC_CONGESTION_CONTROL_RTT_STATS_H_
 #define NET_QUIC_CONGESTION_CONTROL_RTT_STATS_H_
 
 #include <algorithm>
@@ skipping 35 matching lines @@
   QuicTime::Delta smoothed_rtt() const {
     return smoothed_rtt_;
   }
 
   int64 initial_rtt_us() const {
     return initial_rtt_us_;
   }
 
   // Sets an initial RTT to be used for SmoothedRtt before any RTT updates.
   void set_initial_rtt_us(int64 initial_rtt_us) {
+    if (initial_rtt_us <= 0) {
+      LOG(DFATAL) << "Attempt to set initial rtt to <= 0.";
+      return;
+    }
     initial_rtt_us_ = initial_rtt_us;
   }
 
   // The most recent rtt measurement.
   // May return Zero if no valid updates have occurred.
   QuicTime::Delta latest_rtt() const {
     return latest_rtt_;
   }
 
   // Returns the min_rtt for the entire connection.
@@ skipping 49 matching lines @@
   RttSample recent_min_rtt_;  // a in the windowed algorithm.
   RttSample half_window_rtt_;  // b in the sampled algorithm.
   RttSample quarter_window_rtt_;  // c in the sampled algorithm.
 
   DISALLOW_COPY_AND_ASSIGN(RttStats);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_CONGESTION_CONTROL_RTT_STATS_H_