/****************************************************************************
*
* Copyright (c) 2015 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_parameter.h
*
* PX4 Parameter API
*/
#pragma once
#if defined(__PX4_ROS)
/* includes when building for ros */
#include "ros/ros.h"
#include <string>
#else
/* includes when building for NuttX */
#include <systemlib/param/param.h>
#endif
namespace px4
{
/**
* Parameter base class
*/
template <typename T>
class __EXPORT ParameterBase
{
public:
ParameterBase(const char *name, T value) :
_name(name),
_value(value)
{}
virtual ~ParameterBase() {};
/**
* Update the parameter value and return the value
*/
virtual T update() = 0;
/**
* Get the current parameter value
*/
virtual T get() = 0;
protected:
const char *_name; /** The parameter name */
T _value; /**< The current value of the parameter */
};
#if defined(__PX4_ROS)
template <typename T>
class Parameter :
public ParameterBase<T>
{
public:
Parameter(const char *name, T value) :
ParameterBase<T>(name, value)
{
if (!ros::param::has(name)) {
ros::param::set(name, value);
}
update();
}
~Parameter() {};
/**
* Update the parameter value
*/
T update()
{
ros::param::get(this->_name, this->_value);
return get();
}
/**
* Get the current parameter value
*/
T get()
{
return this->_value;
}
};
#else
template <typename T>
class __EXPORT Parameter :
public ParameterBase<T>
{
public:
Parameter(const char *name, T value) :
ParameterBase<T>(name, value),
_handle(param_find(name))
{
update();
}
~Parameter() {};
/**
* Update the parameter value
*/
T update()
{
if (_handle != PARAM_INVALID) {
param_get(_handle, &(this->_value));
}
return get();
}
/**
* Get the current parameter value
*/
T get()
{
return this->_value;
}
protected:
param_t _handle;
};
#endif
typedef Parameter<float> ParameterFloat;
typedef Parameter<int> ParameterInt;
}
