BlockParam.cpp

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

#include "BlockParam.hpp"

#include <cstring>

#include <containers/List.hpp>

namespace control
{

BlockParamBase::BlockParamBase(Block *parent, const char *name, bool parent_prefix)
{
    char fullname[blockNameLengthMax];

    if (parent == nullptr) {
        strncpy(fullname, name, blockNameLengthMax - 1);
        fullname[sizeof(fullname) - 1] = '\0';

    } else {
        char parentName[blockNameLengthMax];
        parent->getName(parentName, blockNameLengthMax);

        if (strcmp(name, "") == 0) {
            strncpy(fullname, parentName, blockNameLengthMax);
            // ensure string is terminated
            fullname[sizeof(fullname) - 1] = '\0';

        } else if (parent_prefix) {
            if (snprintf(fullname, blockNameLengthMax, "%s_%s", parentName, name) >= blockNameLengthMax) {
                PX4_ERR("param too long: %s", name);
            }

        } else {
            strncpy(fullname, name, blockNameLengthMax);
            // ensure string is terminated
            fullname[sizeof(fullname) - 1] = '\0';
        }

        parent->getParams().add(this);
    }

    _handle = param_find(fullname);

    if (_handle == PARAM_INVALID) {
        PX4_ERR("error finding param: %s", fullname);
    }
};

template <>
BlockParam<bool>::BlockParam(Block *block, const char *name, bool parent_prefix) :
    BlockParamBase(block, name, parent_prefix),
    _val()
{
    update();
}

template <>
bool BlockParam<bool>::update()
{
    int32_t tmp = 0;
    int ret = param_get(_handle, &tmp);

    if (tmp == 1) {
        _val = true;

    } else {
        _val = false;
    }

    return (ret == PX4_OK);
}

template <>
BlockParam<int32_t>::BlockParam(Block *block, const char *name, bool parent_prefix) :
    BlockParamBase(block, name, parent_prefix),
    _val()
{
    update();
}

template <>
BlockParam<float>::BlockParam(Block *block, const char *name, bool parent_prefix) :
    BlockParamBase(block, name, parent_prefix),
    _val()
{
    update();
}

template <>
BlockParam<int32_t &>::BlockParam(Block *block, const char *name, bool parent_prefix, int32_t &extern_val) :
    BlockParamBase(block, name, parent_prefix),
    _val(extern_val)
{
    update();
}

template <>
BlockParam<float &>::BlockParam(Block *block, const char *name, bool parent_prefix, float &extern_val) :
    BlockParamBase(block, name, parent_prefix),
    _val(extern_val)
{
    update();
}

} // namespace control