/****************************************************************************
*
* Copyright (c) 2014 PX4 Development Team. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name PX4 nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/**
* @file px4_subscriber.h
*
* PX4 Middleware Wrapper Subscriber
*/
#include <functional>
#pragma once
#if defined(__linux) || (defined(__APPLE__) && defined(__MACH__))
/* includes when building for ros */
#include "ros/ros.h"
#else
/* includes when building for NuttX */
#include <uORB/Subscription.hpp>
#include <containers/List.hpp>
#include "px4_nodehandle.h"
#endif
namespace px4
{
/**
* Untemplated subscriber base class
* */
class SubscriberBase
{
public:
SubscriberBase() {};
~SubscriberBase() {};
};
/**
* Subscriber class which is used by nodehandle
*/
template<typename M>
class Subscriber :
public SubscriberBase
{
public:
Subscriber() :
SubscriberBase()
{};
~Subscriber() {};
/* Accessors*/
/**
* Get the last message value
*/
virtual M get() = 0;
/**
* Get void pointer to last message value
*/
virtual void * get_void_ptr() = 0;
};
#if defined(__linux) || (defined(__APPLE__) && defined(__MACH__))
/**
* Subscriber class that is templated with the ros n message type
*/
template<typename M>
class SubscriberROS :
public Subscriber<M>
{
friend class NodeHandle;
public:
/**
* Construct Subscriber by providing a callback function
*/
SubscriberROS(std::function<void(const M &)> cbf) :
Subscriber<M>(),
_ros_sub(),
_cbf(cbf),
_msg_current()
{}
/**
* Construct Subscriber without a callback function
*/
SubscriberROS() :
Subscriber<M>(),
_ros_sub(),
_cbf(NULL),
_msg_current()
{}
~SubscriberROS() {};
/* Accessors*/
/**
* Get the last message value
*/
M get() { return _msg_current; }
/**
* Get void pointer to last message value
*/
void * get_void_ptr() { return (void*)&_msg_current; }
protected:
/**
* Called on topic update, saves the current message and then calls the provided callback function
*/
void callback(const M &msg) {
/* Store data */
_msg_current = msg;
/* Call callback */
if (_cbf != NULL) {
_cbf(msg);
}
}
/**
* Saves the ros subscriber to keep ros subscription alive
*/
void set_ros_sub(ros::Subscriber ros_sub) {
_ros_sub = ros_sub;
}
ros::Subscriber _ros_sub; /**< Handle to ros subscriber */
std::function<void(const M &)> _cbf; /**< Callback that the user provided on the subscription */
M _msg_current; /**< Current Message value */
};
#else // Building for NuttX
/**
* Subscriber class that is templated with the uorb subscription message type
*/
template<typename M>
class SubscriberUORB :
public Subscriber<M>,
public uORB::Subscription<M>
{
public:
/**
* Construct SubscriberUORB by providing orb meta data without callback
* @param meta orb metadata for the topic which is used
* @param interval Minimal interval between calls to callback
* @param list subscriber is added to this list
*/
SubscriberUORB(const struct orb_metadata *meta,
unsigned interval,
List<uORB::SubscriptionNode *> *list) :
Subscriber<M>(),
uORB::Subscription<M>(meta, interval, list)
{}
~SubscriberUORB() {};
/**
* Update Subscription
* Invoked by the list traversal in NodeHandle::spinOnce
*/
virtual void update()
{
if (!uORB::Subscription<M>::updated()) {
/* Topic not updated */
return;
}
/* get latest data */
uORB::Subscription<M>::update();
};
/* Accessors*/
/**
* Get the last message value
*/
M get() { return uORB::Subscription<M>::getData(); }
/**
* Get void pointer to last message value
*/
void * get_void_ptr() { return uORB::Subscription<M>::getDataVoidPtr(); }
};
template<typename M>
class SubscriberUORBCallback :
public SubscriberUORB<M>
{
public:
/**
* Construct SubscriberUORBCallback by providing orb meta data
* @param meta orb metadata for the topic which is used
* @param callback Callback, executed on receiving a new message
* @param interval Minimal interval between calls to callback
* @param list subscriber is added to this list
*/
SubscriberUORBCallback(const struct orb_metadata *meta,
unsigned interval,
std::function<void(const M &)> callback,
List<uORB::SubscriptionNode *> *list) :
SubscriberUORB<M>(meta, interval, list),
_callback(callback)
{}
~SubscriberUORBCallback() {};
/**
* Update Subscription
* Invoked by the list traversal in NodeHandle::spinOnce
* If new data is available the callback is called
*/
virtual void update()
{
if (!uORB::Subscription<M>::updated()) {
/* Topic not updated, do not call callback */
return;
}
/* get latest data */
uORB::Subscription<M>::update();
/* Check if there is a callback */
if (_callback == nullptr) {
return;
}
/* Call callback which performs actions based on this data */
_callback(uORB::Subscription<M>::getData());
};
protected:
std::function<void(const M &)> _callback; /**< Callback handle,
called when new data is available */
};
#endif
}
