Use overloaded operators with QuicTime for addition, subtraction and scalar

net/quic/quic_connection.cc

 // Copyright (c) 2012 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.
 
 #include "net/quic/quic_connection.h"
 
 #include <string.h>
 #include <sys/types.h>
 
 #include <algorithm>
@@ skipping 1047 matching lines @@
     ++num_retransmittable_packets_received_since_last_ack_sent_;
     if (ack_mode_ != TCP_ACKING &&
         last_header_.packet_number > kMinReceivedBeforeAckDecimation) {
       // Ack up to 10 packets at once.
       if (num_retransmittable_packets_received_since_last_ack_sent_ >=
           kMaxRetransmittablePacketsBeforeAck) {
         ack_queued_ = true;
       } else if (!ack_alarm_->IsSet()) {
         // Wait the minimum of a quarter min_rtt and the delayed ack time.
         QuicTime::Delta ack_delay = QuicTime::Delta::Min(
-            DelayedAckTime(),
-            sent_packet_manager_->GetRttStats()->min_rtt().Multiply(
-                ack_decimation_delay_));
-        ack_alarm_->Set(clock_->ApproximateNow().Add(ack_delay));
+            DelayedAckTime(), sent_packet_manager_->GetRttStats()->min_rtt() *
+                                  ack_decimation_delay_);
+        ack_alarm_->Set(clock_->ApproximateNow() + ack_delay);
       }
     } else {
       // Ack with a timer or every 2 packets by default.
       if (num_retransmittable_packets_received_since_last_ack_sent_ >=
           kDefaultRetransmittablePacketsBeforeAck) {
         ack_queued_ = true;
       } else if (!ack_alarm_->IsSet()) {
-        ack_alarm_->Set(clock_->ApproximateNow().Add(DelayedAckTime()));
+        ack_alarm_->Set(clock_->ApproximateNow() + DelayedAckTime());
       }
     }
 
     // If there are new missing packets to report, send an ack immediately.
     if (received_packet_manager_.HasNewMissingPackets()) {
       if (ack_mode_ == ACK_DECIMATION_WITH_REORDERING) {
         // Wait the minimum of an eighth min_rtt and the existing ack time.
-        QuicTime ack_time = clock_->ApproximateNow().Add(
-            sent_packet_manager_->GetRttStats()->min_rtt().Multiply(0.125));
+        QuicTime ack_time =
+            clock_->ApproximateNow() +
+            0.125 * sent_packet_manager_->GetRttStats()->min_rtt();
         if (!ack_alarm_->IsSet() || ack_alarm_->deadline() > ack_time) {
           ack_alarm_->Cancel();
           ack_alarm_->Set(ack_time);
         }
       } else {
         ack_queued_ = true;
       }
     }
   }
 
@@ skipping 472 matching lines @@
       sent_packet_manager_->TimeUntilSend(now, retransmittable, &path_id);
   if (delay.IsInfinite()) {
     DCHECK_EQ(kInvalidPathId, path_id);
     send_alarm_->Cancel();
     return false;
   }
 
   DCHECK_NE(kInvalidPathId, path_id);
   // If the scheduler requires a delay, then we can not send this packet now.
   if (!delay.IsZero()) {
-    send_alarm_->Update(now.Add(delay), QuicTime::Delta::FromMilliseconds(1));
+    send_alarm_->Update(now + delay, QuicTime::Delta::FromMilliseconds(1));
     DVLOG(1) << ENDPOINT << "Delaying sending " << delay.ToMilliseconds()
              << "ms";
     return false;
   }
   return true;
 }
 
 bool QuicConnection::WritePacket(SerializedPacket* packet) {
   if (packet->packet_number <
       sent_packet_manager_->GetLargestSentPacket(packet->path_id)) {
@@ skipping 542 matching lines @@
 }
 
 void QuicConnection::SetNetworkTimeouts(QuicTime::Delta handshake_timeout,
                                         QuicTime::Delta idle_timeout) {
   QUIC_BUG_IF(idle_timeout > handshake_timeout)
       << "idle_timeout:" << idle_timeout.ToMilliseconds()
       << " handshake_timeout:" << handshake_timeout.ToMilliseconds();
   // Adjust the idle timeout on client and server to prevent clients from
   // sending requests to servers which have already closed the connection.
   if (perspective_ == Perspective::IS_SERVER) {
-    idle_timeout = idle_timeout.Add(QuicTime::Delta::FromSeconds(3));
+    idle_timeout = idle_timeout + QuicTime::Delta::FromSeconds(3);
   } else if (idle_timeout > QuicTime::Delta::FromSeconds(1)) {
-    idle_timeout = idle_timeout.Subtract(QuicTime::Delta::FromSeconds(1));
+    idle_timeout = idle_timeout - QuicTime::Delta::FromSeconds(1);
   }
   handshake_timeout_ = handshake_timeout;
   idle_network_timeout_ = idle_timeout;
 
   SetTimeoutAlarm();
 }
 
 void QuicConnection::CheckForTimeout() {
   QuicTime now = clock_->ApproximateNow();
   QuicTime time_of_last_packet =
       max(time_of_last_received_packet_, last_send_for_timeout_);
 
   // |delta| can be < 0 as |now| is approximate time but |time_of_last_packet|
   // is accurate time. However, this should not change the behavior of
   // timeout handling.
-  QuicTime::Delta idle_duration = now.Subtract(time_of_last_packet);
+  QuicTime::Delta idle_duration = now - time_of_last_packet;
   DVLOG(1) << ENDPOINT << "last packet "
            << time_of_last_packet.ToDebuggingValue()
            << " now:" << now.ToDebuggingValue()
            << " idle_duration:" << idle_duration.ToMicroseconds()
            << " idle_network_timeout: "
            << idle_network_timeout_.ToMicroseconds();
   if (idle_duration >= idle_network_timeout_) {
     const string error_details = "No recent network activity.";
     DVLOG(1) << ENDPOINT << error_details;
     CloseConnection(QUIC_NETWORK_IDLE_TIMEOUT, error_details,
                     idle_timeout_connection_close_behavior_);
     return;
   }
 
   if (!handshake_timeout_.IsInfinite()) {
-    QuicTime::Delta connected_duration =
-        now.Subtract(stats_.connection_creation_time);
+    QuicTime::Delta connected_duration = now - stats_.connection_creation_time;
     DVLOG(1) << ENDPOINT
              << "connection time: " << connected_duration.ToMicroseconds()
              << " handshake timeout: " << handshake_timeout_.ToMicroseconds();
     if (connected_duration >= handshake_timeout_) {
       const string error_details = "Handshake timeout expired.";
       DVLOG(1) << ENDPOINT << error_details;
       CloseConnection(QUIC_HANDSHAKE_TIMEOUT, error_details,
                       ConnectionCloseBehavior::SEND_CONNECTION_CLOSE_PACKET);
       return;
     }
   }
 
   SetTimeoutAlarm();
 }
 
 void QuicConnection::SetTimeoutAlarm() {
   QuicTime time_of_last_packet =
       max(time_of_last_received_packet_, time_of_last_sent_new_packet_);
 
-  QuicTime deadline = time_of_last_packet.Add(idle_network_timeout_);
+  QuicTime deadline = time_of_last_packet + idle_network_timeout_;
   if (!handshake_timeout_.IsInfinite()) {
     deadline =
-        min(deadline, stats_.connection_creation_time.Add(handshake_timeout_));
+        min(deadline, stats_.connection_creation_time + handshake_timeout_);
   }
 
   timeout_alarm_->Cancel();
   timeout_alarm_->Set(deadline);
 }
 
 void QuicConnection::SetPingAlarm() {
   if (perspective_ == Perspective::IS_SERVER) {
     // Only clients send pings.
     return;
   }
   if (!visitor_->HasOpenDynamicStreams()) {
     ping_alarm_->Cancel();
     // Don't send a ping unless there are open streams.
     return;
   }
   QuicTime::Delta ping_timeout = QuicTime::Delta::FromSeconds(kPingTimeoutSecs);
-  ping_alarm_->Update(clock_->ApproximateNow().Add(ping_timeout),
+  ping_alarm_->Update(clock_->ApproximateNow() + ping_timeout,
                       QuicTime::Delta::FromSeconds(1));
 }
 
 void QuicConnection::SetRetransmissionAlarm() {
   if (delay_setting_retransmission_alarm_) {
     pending_retransmission_alarm_ = true;
     return;
   }
   QuicTime retransmission_time = sent_packet_manager_->GetRetransmissionTime();
   retransmission_alarm_->Update(retransmission_time,
@@ skipping 280 matching lines @@
 // the sender and a signaling mechanism -- if the sender uses a
 // different MinRTO, we may get spurious retransmissions. May not have
 // any benefits, but if the delayed ack becomes a significant source
 // of (likely, tail) latency, then consider such a mechanism.
 const QuicTime::Delta QuicConnection::DelayedAckTime() {
   return QuicTime::Delta::FromMilliseconds(
       min(kMaxDelayedAckTimeMs, kMinRetransmissionTimeMs / 2));
 }
 
 }  // namespace net