naiveproxy/net/quic/test_tools/simulator/link.h
2018-02-02 05:49:39 -05:00

101 lines
3.1 KiB
C++

// 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.
#ifndef NET_QUIC_TEST_TOOLS_SIMULATOR_LINK_H_
#define NET_QUIC_TEST_TOOLS_SIMULATOR_LINK_H_
#include <utility>
#include "net/quic/core/crypto/quic_random.h"
#include "net/quic/test_tools/simulator/actor.h"
#include "net/quic/test_tools/simulator/port.h"
namespace net {
namespace simulator {
// A reliable simplex link between two endpoints with constrained bandwidth. A
// few microseconds of random delay are added for every packet to avoid
// synchronization issues.
class OneWayLink : public Actor, public ConstrainedPortInterface {
public:
OneWayLink(Simulator* simulator,
std::string name,
UnconstrainedPortInterface* sink,
QuicBandwidth bandwidth,
QuicTime::Delta propagation_delay);
~OneWayLink() override;
void AcceptPacket(std::unique_ptr<Packet> packet) override;
QuicTime::Delta TimeUntilAvailable() override;
void Act() override;
inline QuicBandwidth bandwidth() const { return bandwidth_; }
inline QuicTime::Delta propagation_delay() const {
return propagation_delay_;
}
private:
struct QueuedPacket {
std::unique_ptr<Packet> packet;
QuicTime dequeue_time;
QueuedPacket(std::unique_ptr<Packet> packet, QuicTime dequeue_time);
QueuedPacket(QueuedPacket&& other);
~QueuedPacket();
};
// Schedule the next packet to be egressed out of the link if there are
// packets on the link.
void ScheduleNextPacketDeparture();
// Get the value of a random delay imposed on each packet in order to avoid
// artifical synchronization artifacts during the simulation.
QuicTime::Delta GetRandomDelay(QuicTime::Delta transfer_time);
UnconstrainedPortInterface* sink_;
QuicQueue<QueuedPacket> packets_in_transit_;
const QuicBandwidth bandwidth_;
const QuicTime::Delta propagation_delay_;
QuicTime next_write_at_;
DISALLOW_COPY_AND_ASSIGN(OneWayLink);
};
// A full-duplex link between two endpoints, functionally equivalent to two
// OneWayLink objects tied together.
class SymmetricLink {
public:
SymmetricLink(Simulator* simulator,
std::string name,
UnconstrainedPortInterface* sink_a,
UnconstrainedPortInterface* sink_b,
QuicBandwidth bandwidth,
QuicTime::Delta propagation_delay);
SymmetricLink(Endpoint* endpoint_a,
Endpoint* endpoint_b,
QuicBandwidth bandwidth,
QuicTime::Delta propagation_delay);
inline ConstrainedPortInterface* GetTxPortForA() { return &a_to_b_link_; }
inline ConstrainedPortInterface* GetTxPortForB() { return &b_to_a_link_; }
inline QuicBandwidth bandwidth() { return a_to_b_link_.bandwidth(); }
inline QuicTime::Delta propagation_delay() {
return a_to_b_link_.propagation_delay();
}
private:
OneWayLink a_to_b_link_;
OneWayLink b_to_a_link_;
DISALLOW_COPY_AND_ASSIGN(SymmetricLink);
};
} // namespace simulator
} // namespace net
#endif // NET_QUIC_TEST_TOOLS_SIMULATOR_LINK_H_