1 // Copyright (c) 2016 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "quiche/quic/test_tools/simulator/traffic_policer.h"
6
7 #include <algorithm>
8
9 namespace quic {
10 namespace simulator {
11
TrafficPolicer(Simulator * simulator,std::string name,QuicByteCount initial_bucket_size,QuicByteCount max_bucket_size,QuicBandwidth target_bandwidth,Endpoint * input)12 TrafficPolicer::TrafficPolicer(Simulator* simulator, std::string name,
13 QuicByteCount initial_bucket_size,
14 QuicByteCount max_bucket_size,
15 QuicBandwidth target_bandwidth, Endpoint* input)
16 : PacketFilter(simulator, name, input),
17 initial_bucket_size_(initial_bucket_size),
18 max_bucket_size_(max_bucket_size),
19 target_bandwidth_(target_bandwidth),
20 last_refill_time_(clock_->Now()) {}
21
~TrafficPolicer()22 TrafficPolicer::~TrafficPolicer() {}
23
Refill()24 void TrafficPolicer::Refill() {
25 QuicTime::Delta time_passed = clock_->Now() - last_refill_time_;
26 QuicByteCount refill_size = time_passed * target_bandwidth_;
27
28 for (auto& bucket : token_buckets_) {
29 bucket.second = std::min(bucket.second + refill_size, max_bucket_size_);
30 }
31
32 last_refill_time_ = clock_->Now();
33 }
34
FilterPacket(const Packet & packet)35 bool TrafficPolicer::FilterPacket(const Packet& packet) {
36 // Refill existing buckets.
37 Refill();
38
39 // Create a new bucket if one does not exist.
40 if (token_buckets_.count(packet.destination) == 0) {
41 token_buckets_.insert(
42 std::make_pair(packet.destination, initial_bucket_size_));
43 }
44
45 auto bucket = token_buckets_.find(packet.destination);
46 QUICHE_DCHECK(bucket != token_buckets_.end());
47
48 // Silently drop the packet on the floor if out of tokens
49 if (bucket->second < packet.size) {
50 return false;
51 }
52
53 bucket->second -= packet.size;
54 return true;
55 }
56
57 } // namespace simulator
58 } // namespace quic
59