px4-firmware/apps/controllib/block/BlockParam.hpp

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/**
 * @file BlockParam.h
 *
 * Controller library code
 */

#pragma once

#include <systemlib/param/param.h>

#include "Block.hpp"
#include "List.hpp"

namespace control
{

/**
 * A base class for block params that enables traversing linked list.
 */
class __EXPORT BlockParamBase : public ListNode<BlockParamBase *>
{
public:
	/**
	 * Instantiate a block param base.
	 *
	 * @param parent_prefix Set to true to include the parent name in the parameter name
	 */
	BlockParamBase(Block *parent, const char *name, bool parent_prefix=true);
	virtual ~BlockParamBase() {};
	virtual void update() = 0;
	const char *getName() { return param_name(_handle); }
protected:
	param_t _handle;
};

/**
 * Parameters that are tied to blocks for updating and nameing.
 */
template<class T>
class __EXPORT BlockParam : public BlockParamBase
{
public:
	BlockParam(Block *block, const char *name, bool parent_prefix=true) :
		BlockParamBase(block, name, parent_prefix),
		_val() {
		update();
	}
	T get() { return _val; }
	void set(T val) { _val = val; }
	void update() {
		if (_handle != PARAM_INVALID) param_get(_handle, &_val);
	}
protected:
	T _val;
};

} // namespace control