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realtime_clock.cpp
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/*
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* Copyright (c) 2013 hiDOF, Inc.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are met:
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*
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* * Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* * Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* * Neither the name of the Willow Garage, Inc. nor the names of its
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* contributors may be used to endorse or promote products derived from
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* this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
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* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
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* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
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* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*/
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/*
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* Publishing ROS messages is difficult, as the publish function is
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* not realtime safe. This class provides the proper locking so that
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* you can call publish in realtime and a separate (non-realtime)
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* thread will ensure that the message gets published over ROS.
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*
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* Author: Wim Meeussen
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*/
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#include <
realtime_tools/realtime_clock.h
>
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namespace
realtime_tools
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{
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RealtimeClock::RealtimeClock
()
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:lock_misses_(0),
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system_time_(
ros
::Time()),
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last_realtime_time_(
ros
::Time()),
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running_(true),
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initialized_(false)
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{
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// thread for time loop
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thread_
= boost::thread(boost::bind(&
RealtimeClock::loop
,
this
));
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}
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RealtimeClock::~RealtimeClock
()
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{
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running_
=
false
;
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thread_
.join();
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}
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ros::Time
RealtimeClock::getSystemTime
(
const
ros::Time
& realtime_time)
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{
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if
(
mutex_
.try_lock())
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{
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// update time offset when we have a new system time measurement in the last cycle
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if
(
lock_misses_
== 0 &&
system_time_
!=
ros::Time
())
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{
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// get additional offset caused by period of realtime loop
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ros::Duration
period_offset;
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if
(
last_realtime_time_
!=
ros::Time
())
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period_offset =
ros::Duration
((realtime_time -
last_realtime_time_
).toSec()/2.0);
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if
(!
initialized_
)
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{
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clock_offset_
=
system_time_
+ period_offset - realtime_time;
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initialized_
=
true
;
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}
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else
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clock_offset_
=
clock_offset_
*0.9999 + (
system_time_
+ period_offset - realtime_time)*0.0001;
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}
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system_time_
=
ros::Time
();
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lock_misses_
= 0;
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mutex_
.unlock();
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}
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else
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lock_misses_
++;
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last_realtime_time_
= realtime_time;
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// return time
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return
realtime_time +
clock_offset_
;
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}
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void
RealtimeClock::loop
()
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{
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ros::Rate
r(750);
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while
(
running_
)
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{
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// get lock
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lock
();
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// store system time
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system_time_
=
ros::Time::now
();
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// warning, using non-locked 'lock_misses_', but it's just for debugging
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if
(
lock_misses_
> 100)
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ROS_WARN_THROTTLE
(1.0,
"Time estimator has trouble transferring data between non-RT and RT"
);
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// release lock
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mutex_
.unlock();
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r.
sleep
();
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}
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}
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void
RealtimeClock::lock
()
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{
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#ifdef NON_POLLING
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mutex_
.lock();
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#else
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while
(!
mutex_
.try_lock())
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usleep(500);
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#endif
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}
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}
// namespace
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realtime_tools::RealtimeClock::lock
void lock()
Definition:
realtime_clock.cpp:123
ros::Time
ros::Rate
realtime_tools::RealtimeClock::initialized_
bool initialized_
Definition:
realtime_clock.h:67
realtime_tools::RealtimeClock::last_realtime_time_
ros::Time last_realtime_time_
Definition:
realtime_clock.h:66
realtime_tools::RealtimeClock::getSystemTime
ros::Time getSystemTime(const ros::Time &realtime_time)
Definition:
realtime_clock.cpp:65
realtime_tools::RealtimeClock::~RealtimeClock
~RealtimeClock()
Definition:
realtime_clock.cpp:57
realtime_clock.h
ROS_WARN_THROTTLE
#define ROS_WARN_THROTTLE(period,...)
realtime_tools::RealtimeClock::mutex_
boost::mutex mutex_
Definition:
realtime_clock.h:68
ros
ros::Rate::sleep
bool sleep()
realtime_tools::RealtimeClock::RealtimeClock
RealtimeClock()
Definition:
realtime_clock.cpp:45
ros::Duration
realtime_tools::RealtimeClock::running_
bool running_
Definition:
realtime_clock.h:67
realtime_tools
Definition:
realtime_box.h:40
realtime_tools::RealtimeClock::lock_misses_
unsigned int lock_misses_
Definition:
realtime_clock.h:62
ros::Time::now
static Time now()
realtime_tools::RealtimeClock::thread_
boost::thread thread_
Definition:
realtime_clock.h:69
realtime_tools::RealtimeClock::system_time_
ros::Time system_time_
Definition:
realtime_clock.h:63
realtime_tools::RealtimeClock::loop
void loop()
Definition:
realtime_clock.cpp:101
realtime_tools::RealtimeClock::clock_offset_
ros::Duration clock_offset_
Definition:
realtime_clock.h:64
realtime_tools
Author(s): Stuart Glaser
autogenerated on Mon Feb 11 2019 03:43:21