managed_resource.h

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#ifndef ROBOT_ACTIVITY_RESOURCE_MANAGED_RESOURCE_H
#define ROBOT_ACTIVITY_RESOURCE_MANAGED_RESOURCE_H

#include <atomic>

#include <ros/ros.h>
#include <ros/console.h>

namespace robot_activity
{
namespace resource
{

class ManagedSubscriber;
class ManagedServiceServer;

template <class Derived, class Resource>
class Managed
{
public:
  Managed() = delete;

  ~Managed();

  template<typename... Args>
  explicit Managed(Args&& ...args)
    : acquired_(false), paused_(true), resource_(), lazy_acquirer_()
  {
    ROS_DEBUG("Managed::ctor");
    lazy_acquirer_ = makeLazyAcquirer(std::forward<Args>(args)...);
  }

  void acquire(const ros::NodeHandlePtr& node_handle);

  void release();

  void pause();

  void resume();

  typedef std::shared_ptr<Managed<Derived, Resource>> SharedPtr;

protected:
  typedef std::function<Resource(const ros::NodeHandlePtr&)> LazyAcquirer;

  template<typename... Args>
  LazyAcquirer makeLazyAcquirer(Args&& ...args) const
  {
    return static_cast<const Derived*>(this)
           ->makeLazyAcquirer(std::forward<Args>(args)...);
  }

  std::atomic<bool> acquired_;

  std::atomic<bool> paused_;


  Resource resource_;

  LazyAcquirer lazy_acquirer_;
};

}  // namespace resource
}  // namespace robot_activity

#endif  // ROBOT_ACTIVITY_RESOURCE_MANAGED_RESOURCE_H