realtime_box.h

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/*
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// Author: Stuart Glaser

#ifndef REALTIME_BOX_H__
#define REALTIME_BOX_H__

#include <string>
#include <ros/node_handle.h>
#include <boost/thread/mutex.hpp>
#include <boost/thread/thread.hpp>

namespace realtime_tools {

template <class T>
class RealtimeBox
{
public:
  RealtimeBox(const T &initial = T()) : thing_(initial)
  {
  }

  void set(const T &value)
  {
    boost::mutex::scoped_lock guard(thing_lock_RT_);
    thing_ = value;
  }

  void get(T &ref)
  {
    boost::mutex::scoped_lock guard(thing_lock_RT_);
    ref = thing_;
  }

private:
  // The thing that's in the box.
  T thing_;

  // Protects access to the thing in the box.  This mutex is
  // guaranteed to be locked for no longer than the duration of the
  // copy, so as long as the copy is realtime safe and the OS has
  // priority inversion for mutexes, this lock can be safely locked
  // from within realtime.
  boost::mutex thing_lock_RT_;
};

} // namespace

#endif