Program Listing for File approximate_time.h
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#ifndef MESSAGE_FILTERS__SYNC_POLICIES__APPROXIMATE_TIME_H_
#define MESSAGE_FILTERS__SYNC_POLICIES__APPROXIMATE_TIME_H_
#include <cassert>
#include <deque>
#include <string>
#include <tuple>
#include <vector>
#include <inttypes.h>
#include <rclcpp/rclcpp.hpp>
#include <rcutils/logging_macros.h>
#include "message_filters/connection.h"
#include "message_filters/message_traits.h"
#include "message_filters/null_types.h"
#include "message_filters/signal9.h"
#include "message_filters/synchronizer.h"
#ifndef RCUTILS_ASSERT
// TODO(tfoote) remove this after it's implemented upstream
// https://github.com/ros2/rcutils/pull/112
#define RCUTILS_ASSERT assert
#endif
#ifndef RCUTILS_BREAK
#include <cassert>
// TODO(tfoote) remove this after it's implemented upstream
// https://github.com/ros2/rcutils/pull/112
#define RCUTILS_BREAK std::abort
#endif
// Uncomment below intead
//#include <rcutils/assert.h>
namespace message_filters
{
namespace sync_policies
{
template<typename M0, typename M1, typename M2 = NullType, typename M3 = NullType, typename M4 = NullType,
typename M5 = NullType, typename M6 = NullType, typename M7 = NullType, typename M8 = NullType>
struct ApproximateTime : public PolicyBase<M0, M1, M2, M3, M4, M5, M6, M7, M8>
{
typedef Synchronizer<ApproximateTime> Sync;
typedef PolicyBase<M0, M1, M2, M3, M4, M5, M6, M7, M8> Super;
typedef typename Super::Messages Messages;
typedef typename Super::Signal Signal;
typedef typename Super::Events Events;
typedef typename Super::RealTypeCount RealTypeCount;
typedef typename Super::M0Event M0Event;
typedef typename Super::M1Event M1Event;
typedef typename Super::M2Event M2Event;
typedef typename Super::M3Event M3Event;
typedef typename Super::M4Event M4Event;
typedef typename Super::M5Event M5Event;
typedef typename Super::M6Event M6Event;
typedef typename Super::M7Event M7Event;
typedef typename Super::M8Event M8Event;
typedef std::deque<M0Event> M0Deque;
typedef std::deque<M1Event> M1Deque;
typedef std::deque<M2Event> M2Deque;
typedef std::deque<M3Event> M3Deque;
typedef std::deque<M4Event> M4Deque;
typedef std::deque<M5Event> M5Deque;
typedef std::deque<M6Event> M6Deque;
typedef std::deque<M7Event> M7Deque;
typedef std::deque<M8Event> M8Deque;
typedef std::vector<M0Event> M0Vector;
typedef std::vector<M1Event> M1Vector;
typedef std::vector<M2Event> M2Vector;
typedef std::vector<M3Event> M3Vector;
typedef std::vector<M4Event> M4Vector;
typedef std::vector<M5Event> M5Vector;
typedef std::vector<M6Event> M6Vector;
typedef std::vector<M7Event> M7Vector;
typedef std::vector<M8Event> M8Vector;
typedef Events Tuple;
typedef std::tuple<M0Deque, M1Deque, M2Deque, M3Deque, M4Deque, M5Deque, M6Deque, M7Deque, M8Deque> DequeTuple;
typedef std::tuple<M0Vector, M1Vector, M2Vector, M3Vector, M4Vector, M5Vector, M6Vector, M7Vector, M8Vector> VectorTuple;
ApproximateTime(uint32_t queue_size)
: parent_(0)
, queue_size_(queue_size)
, num_non_empty_deques_(0)
, pivot_(NO_PIVOT)
, max_interval_duration_(rclcpp::Duration(std::numeric_limits<int32_t>::max(),999999999))
, age_penalty_(0.1)
, has_dropped_messages_(9, false)
, inter_message_lower_bounds_(9, rclcpp::Duration(0, 0))
, warned_about_incorrect_bound_(9, false)
{
RCUTILS_ASSERT(queue_size_ > 0); // The synchronizer will tend to drop many messages with a queue size of 1. At least 2 is recommended.
}
ApproximateTime(const ApproximateTime& e)
: max_interval_duration_(rclcpp::Duration(std::numeric_limits<int32_t>::max(),999999999))
{
*this = e;
}
ApproximateTime& operator=(const ApproximateTime& rhs)
{
parent_ = rhs.parent_;
queue_size_ = rhs.queue_size_;
num_non_empty_deques_ = rhs.num_non_empty_deques_;
pivot_time_ = rhs.pivot_time_;
pivot_ = rhs.pivot_;
max_interval_duration_ = rhs.max_interval_duration_;
age_penalty_ = rhs.age_penalty_;
candidate_start_ = rhs.candidate_start_;
candidate_end_ = rhs.candidate_end_;
deques_ = rhs.deques_;
past_ = rhs.past_;
has_dropped_messages_ = rhs.has_dropped_messages_;
inter_message_lower_bounds_ = rhs.inter_message_lower_bounds_;
warned_about_incorrect_bound_ = rhs.warned_about_incorrect_bound_;
return *this;
}
void initParent(Sync* parent)
{
parent_ = parent;
}
template<int i>
void checkInterMessageBound()
{
namespace mt = message_filters::message_traits;
if (warned_about_incorrect_bound_[i])
{
return;
}
std::deque<typename std::tuple_element<i, Events>::type>& deque = std::get<i>(deques_);
std::vector<typename std::tuple_element<i, Events>::type>& v = std::get<i>(past_);
RCUTILS_ASSERT(!deque.empty());
const typename std::tuple_element<i, Messages>::type &msg = *(deque.back()).getMessage();
rclcpp::Time msg_time = mt::TimeStamp<typename std::tuple_element<i, Messages>::type>::value(msg);
rclcpp::Time previous_msg_time;
if (deque.size() == (size_t) 1)
{
if (v.empty())
{
// We have already published (or have never received) the previous message, we cannot check the bound
return;
}
const typename std::tuple_element<i, Messages>::type &previous_msg = *(v.back()).getMessage();
previous_msg_time = mt::TimeStamp<typename std::tuple_element<i, Messages>::type>::value(previous_msg);
}
else
{
// There are at least 2 elements in the deque. Check that the gap respects the bound if it was provided.
const typename std::tuple_element<i, Messages>::type &previous_msg = *(deque[deque.size()-2]).getMessage();
previous_msg_time = mt::TimeStamp<typename std::tuple_element<i, Messages>::type>::value(previous_msg);
}
if (msg_time < previous_msg_time)
{
RCUTILS_LOG_WARN_ONCE("Messages of type %d arrived out of order (will print only once)", i);
warned_about_incorrect_bound_[i] = true;
}
else if ((msg_time - previous_msg_time) < inter_message_lower_bounds_[i])
{
RCUTILS_LOG_WARN_ONCE("Messages of type %d arrived closer ("
"%" PRId64 ") than the lower bound you provided ("
"%" PRId64 ") (will print only once)",
i,
(msg_time - previous_msg_time).nanoseconds(),
inter_message_lower_bounds_[i].nanoseconds());
warned_about_incorrect_bound_[i] = true;
}
}
template<int i>
void add(const typename std::tuple_element<i, Events>::type& evt)
{
std::lock_guard<std::mutex> lock(data_mutex_);
std::deque<typename std::tuple_element<i, Events>::type>& deque = std::get<i>(deques_);
deque.push_back(evt);
if (deque.size() == (size_t)1) {
// We have just added the first message, so it was empty before
++num_non_empty_deques_;
if (num_non_empty_deques_ == (uint32_t)RealTypeCount::value)
{
// All deques have messages
process();
}
}
else
{
checkInterMessageBound<i>();
}
// Check whether we have more messages than allowed in the queue.
// Note that during the above call to process(), queue i may contain queue_size_+1 messages.
std::vector<typename std::tuple_element<i, Events>::type>& past = std::get<i>(past_);
if (deque.size() + past.size() > queue_size_)
{
// Cancel ongoing candidate search, if any:
num_non_empty_deques_ = 0; // We will recompute it from scratch
recover<0>();
recover<1>();
recover<2>();
recover<3>();
recover<4>();
recover<5>();
recover<6>();
recover<7>();
recover<8>();
// Drop the oldest message in the offending topic
RCUTILS_ASSERT(!deque.empty());
deque.pop_front();
has_dropped_messages_[i] = true;
if (pivot_ != NO_PIVOT)
{
// The candidate is no longer valid. Destroy it.
candidate_ = Tuple();
pivot_ = NO_PIVOT;
// There might still be enough messages to create a new candidate:
process();
}
}
}
void setAgePenalty(double age_penalty)
{
// For correctness we only need age_penalty > -1.0, but most likely a negative age_penalty is a mistake.
RCUTILS_ASSERT(age_penalty >= 0);
age_penalty_ = age_penalty;
}
void setInterMessageLowerBound(int i, rclcpp::Duration lower_bound) {
// For correctness we only need age_penalty > -1.0, but most likely a negative age_penalty is a mistake.
RCUTILS_ASSERT(lower_bound >= rclcpp::Duration(0,0));
inter_message_lower_bounds_[i] = lower_bound;
}
void setMaxIntervalDuration(rclcpp::Duration max_interval_duration) {
// For correctness we only need age_penalty > -1.0, but most likely a negative age_penalty is a mistake.
RCUTILS_ASSERT(max_interval_duration >= rclcpp::Duration(0,0));
max_interval_duration_ = max_interval_duration;
}
private:
// Assumes that deque number <index> is non empty
template<int i>
void dequeDeleteFront()
{
std::deque<typename std::tuple_element<i, Events>::type>& deque = std::get<i>(deques_);
RCUTILS_ASSERT(!deque.empty());
deque.pop_front();
if (deque.empty())
{
--num_non_empty_deques_;
}
}
// Assumes that deque number <index> is non empty
void dequeDeleteFront(uint32_t index)
{
switch (index)
{
case 0:
dequeDeleteFront<0>();
break;
case 1:
dequeDeleteFront<1>();
break;
case 2:
dequeDeleteFront<2>();
break;
case 3:
dequeDeleteFront<3>();
break;
case 4:
dequeDeleteFront<4>();
break;
case 5:
dequeDeleteFront<5>();
break;
case 6:
dequeDeleteFront<6>();
break;
case 7:
dequeDeleteFront<7>();
break;
case 8:
dequeDeleteFront<8>();
break;
default:
RCUTILS_BREAK();
}
}
// Assumes that deque number <index> is non empty
template<int i>
void dequeMoveFrontToPast()
{
std::deque<typename std::tuple_element<i, Events>::type>& deque = std::get<i>(deques_);
std::vector<typename std::tuple_element<i, Events>::type>& vector = std::get<i>(past_);
RCUTILS_ASSERT(!deque.empty());
vector.push_back(deque.front());
deque.pop_front();
if (deque.empty())
{
--num_non_empty_deques_;
}
}
// Assumes that deque number <index> is non empty
void dequeMoveFrontToPast(uint32_t index)
{
switch (index)
{
case 0:
dequeMoveFrontToPast<0>();
break;
case 1:
dequeMoveFrontToPast<1>();
break;
case 2:
dequeMoveFrontToPast<2>();
break;
case 3:
dequeMoveFrontToPast<3>();
break;
case 4:
dequeMoveFrontToPast<4>();
break;
case 5:
dequeMoveFrontToPast<5>();
break;
case 6:
dequeMoveFrontToPast<6>();
break;
case 7:
dequeMoveFrontToPast<7>();
break;
case 8:
dequeMoveFrontToPast<8>();
break;
default:
RCUTILS_BREAK();
}
}
void makeCandidate()
{
//printf("Creating candidate\n");
// Create candidate tuple
candidate_ = Tuple(); // Discards old one if any
std::get<0>(candidate_) = std::get<0>(deques_).front();
std::get<1>(candidate_) = std::get<1>(deques_).front();
if (RealTypeCount::value > 2)
{
std::get<2>(candidate_) = std::get<2>(deques_).front();
if (RealTypeCount::value > 3)
{
std::get<3>(candidate_) = std::get<3>(deques_).front();
if (RealTypeCount::value > 4)
{
std::get<4>(candidate_) = std::get<4>(deques_).front();
if (RealTypeCount::value > 5)
{
std::get<5>(candidate_) = std::get<5>(deques_).front();
if (RealTypeCount::value > 6)
{
std::get<6>(candidate_) = std::get<6>(deques_).front();
if (RealTypeCount::value > 7)
{
std::get<7>(candidate_) = std::get<7>(deques_).front();
if (RealTypeCount::value > 8)
{
std::get<8>(candidate_) = std::get<8>(deques_).front();
}
}
}
}
}
}
}
// Delete all past messages, since we have found a better candidate
std::get<0>(past_).clear();
std::get<1>(past_).clear();
std::get<2>(past_).clear();
std::get<3>(past_).clear();
std::get<4>(past_).clear();
std::get<5>(past_).clear();
std::get<6>(past_).clear();
std::get<7>(past_).clear();
std::get<8>(past_).clear();
//printf("Candidate created\n");
}
// ASSUMES: num_messages <= past_[i].size()
template<int i>
void recover(size_t num_messages)
{
if (i >= RealTypeCount::value)
{
return;
}
std::vector<typename std::tuple_element<i, Events>::type>& v = std::get<i>(past_);
std::deque<typename std::tuple_element<i, Events>::type>& q = std::get<i>(deques_);
RCUTILS_ASSERT(num_messages <= v.size());
while (num_messages > 0)
{
q.push_front(v.back());
v.pop_back();
num_messages--;
}
if (!q.empty())
{
++num_non_empty_deques_;
}
}
template<int i>
void recover()
{
if (i >= RealTypeCount::value)
{
return;
}
std::vector<typename std::tuple_element<i, Events>::type>& v = std::get<i>(past_);
std::deque<typename std::tuple_element<i, Events>::type>& q = std::get<i>(deques_);
while (!v.empty())
{
q.push_front(v.back());
v.pop_back();
}
if (!q.empty())
{
++num_non_empty_deques_;
}
}
template<int i>
void recoverAndDelete()
{
if (i >= RealTypeCount::value)
{
return;
}
std::vector<typename std::tuple_element<i, Events>::type>& v = std::get<i>(past_);
std::deque<typename std::tuple_element<i, Events>::type>& q = std::get<i>(deques_);
while (!v.empty())
{
q.push_front(v.back());
v.pop_back();
}
RCUTILS_ASSERT(!q.empty());
q.pop_front();
if (!q.empty())
{
++num_non_empty_deques_;
}
}
// Assumes: all deques are non empty, i.e. num_non_empty_deques_ == RealTypeCount::value
void publishCandidate()
{
//printf("Publishing candidate\n");
// Publish
parent_->signal(std::get<0>(candidate_), std::get<1>(candidate_), std::get<2>(candidate_), std::get<3>(candidate_),
std::get<4>(candidate_), std::get<5>(candidate_), std::get<6>(candidate_), std::get<7>(candidate_),
std::get<8>(candidate_));
// Delete this candidate
candidate_ = Tuple();
pivot_ = NO_PIVOT;
// Recover hidden messages, and delete the ones corresponding to the candidate
num_non_empty_deques_ = 0; // We will recompute it from scratch
recoverAndDelete<0>();
recoverAndDelete<1>();
recoverAndDelete<2>();
recoverAndDelete<3>();
recoverAndDelete<4>();
recoverAndDelete<5>();
recoverAndDelete<6>();
recoverAndDelete<7>();
recoverAndDelete<8>();
}
// Assumes: all deques are non empty, i.e. num_non_empty_deques_ == RealTypeCount::value
// Returns: the oldest message on the deques
void getCandidateStart(uint32_t &start_index, rclcpp::Time &start_time)
{
return getCandidateBoundary(start_index, start_time, false);
}
// Assumes: all deques are non empty, i.e. num_non_empty_deques_ == RealTypeCount::value
// Returns: the latest message among the heads of the deques, i.e. the minimum
// time to end an interval started at getCandidateStart_index()
void getCandidateEnd(uint32_t &end_index, rclcpp::Time &end_time)
{
return getCandidateBoundary(end_index, end_time, true);
}
// ASSUMES: all deques are non-empty
// end = true: look for the latest head of deque
// false: look for the earliest head of deque
void getCandidateBoundary(uint32_t &index, rclcpp::Time &time, bool end)
{
namespace mt = message_filters::message_traits;
M0Event& m0 = std::get<0>(deques_).front();
time = mt::TimeStamp<M0>::value(*m0.getMessage());
index = 0;
if (RealTypeCount::value > 1)
{
M1Event& m1 = std::get<1>(deques_).front();
if ((mt::TimeStamp<M1>::value(*m1.getMessage()) < time) ^ end)
{
time = mt::TimeStamp<M1>::value(*m1.getMessage());
index = 1;
}
}
if (RealTypeCount::value > 2)
{
M2Event& m2 = std::get<2>(deques_).front();
if ((mt::TimeStamp<M2>::value(*m2.getMessage()) < time) ^ end)
{
time = mt::TimeStamp<M2>::value(*m2.getMessage());
index = 2;
}
}
if (RealTypeCount::value > 3)
{
M3Event& m3 = std::get<3>(deques_).front();
if ((mt::TimeStamp<M3>::value(*m3.getMessage()) < time) ^ end)
{
time = mt::TimeStamp<M3>::value(*m3.getMessage());
index = 3;
}
}
if (RealTypeCount::value > 4)
{
M4Event& m4 = std::get<4>(deques_).front();
if ((mt::TimeStamp<M4>::value(*m4.getMessage()) < time) ^ end)
{
time = mt::TimeStamp<M4>::value(*m4.getMessage());
index = 4;
}
}
if (RealTypeCount::value > 5)
{
M5Event& m5 = std::get<5>(deques_).front();
if ((mt::TimeStamp<M5>::value(*m5.getMessage()) < time) ^ end)
{
time = mt::TimeStamp<M5>::value(*m5.getMessage());
index = 5;
}
}
if (RealTypeCount::value > 6)
{
M6Event& m6 = std::get<6>(deques_).front();
if ((mt::TimeStamp<M6>::value(*m6.getMessage()) < time) ^ end)
{
time = mt::TimeStamp<M6>::value(*m6.getMessage());
index = 6;
}
}
if (RealTypeCount::value > 7)
{
M7Event& m7 = std::get<7>(deques_).front();
if ((mt::TimeStamp<M7>::value(*m7.getMessage()) < time) ^ end)
{
time = mt::TimeStamp<M7>::value(*m7.getMessage());
index = 7;
}
}
if (RealTypeCount::value > 8)
{
M8Event& m8 = std::get<8>(deques_).front();
if ((mt::TimeStamp<M8>::value(*m8.getMessage()) < time) ^ end)
{
time = mt::TimeStamp<M8>::value(*m8.getMessage());
index = 8;
}
}
}
// ASSUMES: we have a pivot and candidate
template<int i>
rclcpp::Time getVirtualTime()
{
namespace mt = message_filters::message_traits;
if (i >= RealTypeCount::value)
{
return rclcpp::Time(0,0); // Dummy return value
}
RCUTILS_ASSERT(pivot_ != NO_PIVOT);
std::vector<typename std::tuple_element<i, Events>::type>& v = std::get<i>(past_);
std::deque<typename std::tuple_element<i, Events>::type>& q = std::get<i>(deques_);
if (q.empty())
{
RCUTILS_ASSERT(!v.empty()); // Because we have a candidate
rclcpp::Time last_msg_time = mt::TimeStamp<typename std::tuple_element<i, Messages>::type>::value(*(v.back()).getMessage());
rclcpp::Time msg_time_lower_bound = last_msg_time + inter_message_lower_bounds_[i];
if (msg_time_lower_bound > pivot_time_) // Take the max
{
return msg_time_lower_bound;
}
return pivot_time_;
}
rclcpp::Time current_msg_time = mt::TimeStamp<typename std::tuple_element<i, Messages>::type>::value(*(q.front()).getMessage());
return current_msg_time;
}
// ASSUMES: we have a pivot and candidate
void getVirtualCandidateStart(uint32_t &start_index, rclcpp::Time &start_time)
{
return getVirtualCandidateBoundary(start_index, start_time, false);
}
// ASSUMES: we have a pivot and candidate
void getVirtualCandidateEnd(uint32_t &end_index, rclcpp::Time &end_time)
{
return getVirtualCandidateBoundary(end_index, end_time, true);
}
// ASSUMES: we have a pivot and candidate
// end = true: look for the latest head of deque
// false: look for the earliest head of deque
void getVirtualCandidateBoundary(uint32_t &index, rclcpp::Time &time, bool end)
{
std::vector<rclcpp::Time> virtual_times(9);
virtual_times[0] = getVirtualTime<0>();
virtual_times[1] = getVirtualTime<1>();
virtual_times[2] = getVirtualTime<2>();
virtual_times[3] = getVirtualTime<3>();
virtual_times[4] = getVirtualTime<4>();
virtual_times[5] = getVirtualTime<5>();
virtual_times[6] = getVirtualTime<6>();
virtual_times[7] = getVirtualTime<7>();
virtual_times[8] = getVirtualTime<8>();
time = virtual_times[0];
index = 0;
for (int i = 0; i < RealTypeCount::value; i++)
{
if ((virtual_times[i] < time) ^ end)
{
time = virtual_times[i];
index = i;
}
}
}
// assumes data_mutex_ is already locked
void process()
{
// While no deque is empty
while (num_non_empty_deques_ == (uint32_t)RealTypeCount::value)
{
// Find the start and end of the current interval
//printf("Entering while loop in this state [\n");
//show_internal_state();
//printf("]\n");
rclcpp::Time end_time, start_time;
uint32_t end_index, start_index;
getCandidateEnd(end_index, end_time);
getCandidateStart(start_index, start_time);
for (uint32_t i = 0; i < (uint32_t)RealTypeCount::value; i++)
{
if (i != end_index)
{
// No dropped message could have been better to use than the ones we have,
// so it becomes ok to use this topic as pivot in the future
has_dropped_messages_[i] = false;
}
}
if (pivot_ == NO_PIVOT)
{
// We do not have a candidate
// INVARIANT: the past_ vectors are empty
// INVARIANT: (candidate_ has no filled members)
if (end_time - start_time > max_interval_duration_)
{
// This interval is too big to be a valid candidate, move to the next
dequeDeleteFront(start_index);
continue;
}
if (has_dropped_messages_[end_index])
{
// The topic that would become pivot has dropped messages, so it is not a good pivot
dequeDeleteFront(start_index);
continue;
}
// This is a valid candidate, and we don't have any, so take it
makeCandidate();
candidate_start_ = start_time;
candidate_end_ = end_time;
pivot_ = end_index;
pivot_time_ = end_time;
dequeMoveFrontToPast(start_index);
}
else
{
// We already have a candidate
// Is this one better than the current candidate?
// INVARIANT: has_dropped_messages_ is all false
if ((end_time - candidate_end_) * (1 + age_penalty_) >= (start_time - candidate_start_))
{
// This is not a better candidate, move to the next
dequeMoveFrontToPast(start_index);
}
else
{
// This is a better candidate
makeCandidate();
candidate_start_ = start_time;
candidate_end_ = end_time;
dequeMoveFrontToPast(start_index);
// Keep the same pivot (and pivot time)
}
}
// INVARIANT: we have a candidate and pivot
RCUTILS_ASSERT(pivot_ != NO_PIVOT);
//printf("start_index == %d, pivot_ == %d\n", start_index, pivot_);
if (start_index == pivot_) // TODO: replace with start_time == pivot_time_
{
// We have exhausted all possible candidates for this pivot, we now can output the best one
publishCandidate();
}
else if ((end_time - candidate_end_) * (1 + age_penalty_) >= (pivot_time_ - candidate_start_))
{
// We have not exhausted all candidates, but this candidate is already provably optimal
// Indeed, any future candidate must contain the interval [pivot_time_ end_time], which
// is already too big.
// Note: this case is subsumed by the next, but it may save some unnecessary work and
// it makes things (a little) easier to understand
publishCandidate();
}
else if (num_non_empty_deques_ < (uint32_t)RealTypeCount::value)
{
uint32_t num_non_empty_deques_before_virtual_search = num_non_empty_deques_;
// Before giving up, use the rate bounds, if provided, to further try to prove optimality
std::vector<int> num_virtual_moves(9,0);
while (1)
{
rclcpp::Time end_time, start_time;
uint32_t end_index, start_index;
getVirtualCandidateEnd(end_index, end_time);
getVirtualCandidateStart(start_index, start_time);
if ((end_time - candidate_end_) * (1 + age_penalty_) >= (pivot_time_ - candidate_start_))
{
// We have proved optimality
// As above, any future candidate must contain the interval [pivot_time_ end_time], which
// is already too big.
publishCandidate(); // This cleans up the virtual moves as a byproduct
break; // From the while(1) loop only
}
if ((end_time - candidate_end_) * (1 + age_penalty_) < (start_time - candidate_start_))
{
// We cannot prove optimality
// Indeed, we have a virtual (i.e. optimistic) candidate that is better than the current
// candidate
// Cleanup the virtual search:
num_non_empty_deques_ = 0; // We will recompute it from scratch
recover<0>(num_virtual_moves[0]);
recover<1>(num_virtual_moves[1]);
recover<2>(num_virtual_moves[2]);
recover<3>(num_virtual_moves[3]);
recover<4>(num_virtual_moves[4]);
recover<5>(num_virtual_moves[5]);
recover<6>(num_virtual_moves[6]);
recover<7>(num_virtual_moves[7]);
recover<8>(num_virtual_moves[8]);
(void)num_non_empty_deques_before_virtual_search; // unused variable warning stopper
RCUTILS_ASSERT(num_non_empty_deques_before_virtual_search == num_non_empty_deques_);
break;
}
// Note: we cannot reach this point with start_index == pivot_ since in that case we would
// have start_time == pivot_time, in which case the two tests above are the negation
// of each other, so that one must be true. Therefore the while loop always terminates.
RCUTILS_ASSERT(start_index != pivot_);
RCUTILS_ASSERT(start_time < pivot_time_);
dequeMoveFrontToPast(start_index);
num_virtual_moves[start_index]++;
} // while(1)
}
} // while(num_non_empty_deques_ == (uint32_t)RealTypeCount::value)
}
Sync* parent_;
uint32_t queue_size_;
static const uint32_t NO_PIVOT = 9; // Special value for the pivot indicating that no pivot has been selected
DequeTuple deques_;
uint32_t num_non_empty_deques_;
VectorTuple past_;
Tuple candidate_; // NULL if there is no candidate, in which case there is no pivot.
rclcpp::Time candidate_start_;
rclcpp::Time candidate_end_;
rclcpp::Time pivot_time_;
uint32_t pivot_; // Equal to NO_PIVOT if there is no candidate
std::mutex data_mutex_; // Protects all of the above
rclcpp::Duration max_interval_duration_; // TODO: initialize with a parameter
double age_penalty_;
std::vector<bool> has_dropped_messages_;
std::vector<rclcpp::Duration> inter_message_lower_bounds_;
std::vector<bool> warned_about_incorrect_bound_;
};
} // namespace sync
} // namespace message_filters
#endif // MESSAGE_FILTERS__SYNC_POLICIES__APPROXIMATE_TIME_H_