blob: 9aa10ab039683605ba9a585ef67ae24eb2959071 [file] [log] [blame]
// 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 "quic/test_tools/simulator/simulator.h"
#include "quic/core/crypto/quic_random.h"
#include "quic/platform/api/quic_logging.h"
namespace quic {
namespace simulator {
Simulator::Simulator() : Simulator(nullptr) {}
Simulator::Simulator(QuicRandom* random_generator)
: random_generator_(random_generator),
alarm_factory_(this, "Default Alarm Manager"),
run_for_should_stop_(false),
enable_random_delays_(false) {
run_for_alarm_.reset(
alarm_factory_.CreateAlarm(new RunForDelegate(&run_for_should_stop_)));
}
Simulator::~Simulator() {
// Ensure that Actor under run_for_alarm_ is removed before Simulator data
// structures are destructed.
run_for_alarm_.reset();
}
Simulator::Clock::Clock() : now_(kStartTime) {}
QuicTime Simulator::Clock::ApproximateNow() const {
return now_;
}
QuicTime Simulator::Clock::Now() const {
return now_;
}
QuicWallTime Simulator::Clock::WallNow() const {
return QuicWallTime::FromUNIXMicroseconds(
(now_ - QuicTime::Zero()).ToMicroseconds());
}
void Simulator::AddActor(Actor* actor) {
auto emplace_times_result =
scheduled_times_.insert(std::make_pair(actor, QuicTime::Infinite()));
auto emplace_names_result = actor_names_.insert(actor->name());
// Ensure that the object was actually placed into the map.
DCHECK(emplace_times_result.second);
DCHECK(emplace_names_result.second);
}
void Simulator::RemoveActor(Actor* actor) {
auto scheduled_time_it = scheduled_times_.find(actor);
auto actor_names_it = actor_names_.find(actor->name());
DCHECK(scheduled_time_it != scheduled_times_.end());
DCHECK(actor_names_it != actor_names_.end());
QuicTime scheduled_time = scheduled_time_it->second;
if (scheduled_time != QuicTime::Infinite()) {
Unschedule(actor);
}
scheduled_times_.erase(scheduled_time_it);
actor_names_.erase(actor_names_it);
}
void Simulator::Schedule(Actor* actor, QuicTime new_time) {
auto scheduled_time_it = scheduled_times_.find(actor);
DCHECK(scheduled_time_it != scheduled_times_.end());
QuicTime scheduled_time = scheduled_time_it->second;
if (scheduled_time <= new_time) {
return;
}
if (scheduled_time != QuicTime::Infinite()) {
Unschedule(actor);
}
scheduled_time_it->second = new_time;
schedule_.insert(std::make_pair(new_time, actor));
}
void Simulator::Unschedule(Actor* actor) {
auto scheduled_time_it = scheduled_times_.find(actor);
DCHECK(scheduled_time_it != scheduled_times_.end());
QuicTime scheduled_time = scheduled_time_it->second;
DCHECK(scheduled_time != QuicTime::Infinite());
auto range = schedule_.equal_range(scheduled_time);
for (auto it = range.first; it != range.second; ++it) {
if (it->second == actor) {
schedule_.erase(it);
scheduled_time_it->second = QuicTime::Infinite();
return;
}
}
DCHECK(false);
}
const QuicClock* Simulator::GetClock() const {
return &clock_;
}
QuicRandom* Simulator::GetRandomGenerator() {
if (random_generator_ == nullptr) {
random_generator_ = QuicRandom::GetInstance();
}
return random_generator_;
}
QuicBufferAllocator* Simulator::GetStreamSendBufferAllocator() {
return &buffer_allocator_;
}
QuicAlarmFactory* Simulator::GetAlarmFactory() {
return &alarm_factory_;
}
Simulator::RunForDelegate::RunForDelegate(bool* run_for_should_stop)
: run_for_should_stop_(run_for_should_stop) {}
void Simulator::RunForDelegate::OnAlarm() {
*run_for_should_stop_ = true;
}
void Simulator::RunFor(QuicTime::Delta time_span) {
DCHECK(!run_for_alarm_->IsSet());
// RunFor() ensures that the simulation stops at the exact time specified by
// scheduling an alarm at that point and using that alarm to abort the
// simulation. An alarm is necessary because otherwise it is possible that
// nothing is scheduled at |end_time|, so the simulation will either go
// further than requested or stop before reaching |end_time|.
const QuicTime end_time = clock_.Now() + time_span;
run_for_alarm_->Set(end_time);
run_for_should_stop_ = false;
bool simulation_result = RunUntil([this]() { return run_for_should_stop_; });
DCHECK(simulation_result);
DCHECK(clock_.Now() == end_time);
}
void Simulator::HandleNextScheduledActor() {
const auto current_event_it = schedule_.begin();
QuicTime event_time = current_event_it->first;
Actor* actor = current_event_it->second;
QUIC_DVLOG(3) << "At t = " << event_time.ToDebuggingValue() << ", calling "
<< actor->name();
Unschedule(actor);
if (clock_.Now() > event_time) {
QUIC_BUG << "Error: event registered by [" << actor->name()
<< "] requires travelling back in time. Current time: "
<< clock_.Now().ToDebuggingValue()
<< ", scheduled time: " << event_time.ToDebuggingValue();
}
clock_.now_ = event_time;
actor->Act();
}
} // namespace simulator
} // namespace quic