BlockParam.hpp

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

#pragma once

#include "Block.hpp"

#include <containers/List.hpp>
#include <px4_platform_common/defines.h>
#include <parameters/param.h>

namespace control
{

class Block;

// A base class for block params that enables traversing linked list.
class 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() = default;

    virtual bool update() = 0;
    const char *getName() const { return param_name(_handle); }

protected:
    param_t _handle{PARAM_INVALID};
};

// Parameters that are tied to blocks for updating and naming.
template <class T>
class __EXPORT BlockParam final : public BlockParamBase
{
public:
    BlockParam(Block *block, const char *name, bool parent_prefix = true);
    BlockParam(Block *block, const char *name, bool parent_prefix, T &extern_val);

    ~BlockParam() override = default;

    // no copy, assignment, move, move assignment
    BlockParam(const BlockParam &) = delete;
    BlockParam &operator=(const BlockParam &) = delete;
    BlockParam(BlockParam &&) = delete;
    BlockParam &operator=(BlockParam &&) = delete;

    T get() const { return _val; }

    // Store the parameter value to the parameter storage (@see param_set())
    bool commit() { return (param_set(_handle, &_val) == PX4_OK); }

    // Store the parameter value to the parameter storage, w/o notifying the system (@see param_set_no_notification())
    bool commit_no_notification() { return (param_set_no_notification(_handle, &_val) == PX4_OK); }

    void set(T val) { _val = val; }

    bool update() override { return (param_get(_handle, &_val) == PX4_OK); }

protected:
    T _val;
};

template <>
bool BlockParam<bool>::update();

typedef BlockParam<float> BlockParamFloat;
typedef BlockParam<int32_t> BlockParamInt;
typedef BlockParam<bool> BlockParamBool;
typedef BlockParam<float &> BlockParamExtFloat;
typedef BlockParam<int32_t &> BlockParamExtInt;

} // namespace control