146 lines
4.4 KiB
C++
146 lines
4.4 KiB
C++
#ifndef RFL_PARSING_TUPLEREADER_HPP_
|
|
#define RFL_PARSING_TUPLEREADER_HPP_
|
|
|
|
#include <string_view>
|
|
#include <tuple>
|
|
#include <type_traits>
|
|
#include <vector>
|
|
|
|
#include "../Result.hpp"
|
|
#include "../internal/is_array.hpp"
|
|
|
|
namespace rfl::parsing {
|
|
|
|
template <
|
|
class R,
|
|
class W,
|
|
class TupleType,
|
|
bool _ignore_empty_containers,
|
|
bool _all_required,
|
|
class ProcessorsType>
|
|
class TupleReader {
|
|
private:
|
|
using InputVarType = typename R::InputVarType;
|
|
static constexpr size_t size_ = std::tuple_size_v<TupleType>;
|
|
|
|
public:
|
|
TupleReader(const R* _r, TupleType* _tuple) : i_(0), r_(_r), tuple_(_tuple) {}
|
|
|
|
~TupleReader() = default;
|
|
|
|
std::optional<Error> handle_missing_fields() const {
|
|
std::optional<Error> err;
|
|
if (i_ < size_) {
|
|
handle_missing_fields_impl(&err);
|
|
}
|
|
return err;
|
|
}
|
|
|
|
std::optional<Error> read(const InputVarType& _var) const {
|
|
std::optional<Error> err;
|
|
read_impl(_var, &err);
|
|
return err;
|
|
}
|
|
|
|
/// Because of the way we have allocated the fields, we need to manually
|
|
/// trigger the destructors.
|
|
template <size_t _i = 0>
|
|
void call_destructors_where_necessary() const {
|
|
if constexpr (_i < size_) {
|
|
if (_i >= i_) {
|
|
return;
|
|
}
|
|
using CurrentType = std::remove_cvref_t<std::tuple_element_t<_i, TupleType>>;
|
|
if constexpr (!std::is_array_v<CurrentType> && std::is_pointer_v<CurrentType> &&
|
|
std::is_destructible_v<CurrentType>) {
|
|
std::get<_i>(*tuple_)->~CurrentType();
|
|
} else if constexpr (std::is_array_v<CurrentType>) {
|
|
auto ptr = std::get<_i>(*tuple_);
|
|
call_destructor_on_array(sizeof(*ptr) / sizeof(**ptr), *ptr);
|
|
}
|
|
call_destructors_where_necessary<_i + 1>();
|
|
}
|
|
}
|
|
|
|
private:
|
|
template <int _i = 0>
|
|
void handle_missing_fields_impl(std::optional<Error>* _err) const noexcept {
|
|
if constexpr (_i < size_) {
|
|
if (i_ == _i) {
|
|
using CurrentType = std::remove_cvref_t<std::tuple_element_t<_i, TupleType>>;
|
|
|
|
if constexpr (_all_required || is_required<CurrentType, _ignore_empty_containers>()) {
|
|
*_err = Error("Field " + std::to_string(_i) + " was required, but missing.");
|
|
return;
|
|
} else {
|
|
::new (&(std::get<_i>(*tuple_))) CurrentType();
|
|
++i_;
|
|
}
|
|
}
|
|
handle_missing_fields_impl<_i + 1>(_err);
|
|
}
|
|
}
|
|
|
|
template <size_t _i = 0>
|
|
void read_impl(const InputVarType& _var, std::optional<Error>* _err) const {
|
|
if constexpr (_i < size_) {
|
|
if (i_ == _i) {
|
|
using CurrentType = std::remove_cvref_t<std::tuple_element_t<_i, TupleType>>;
|
|
|
|
auto res = Parser<R, W, CurrentType, ProcessorsType>::read(*r_, _var);
|
|
|
|
if (res) {
|
|
move_to(&(std::get<_i>(*tuple_)), &(*res));
|
|
++i_;
|
|
} else {
|
|
*_err =
|
|
Error("Failed to parse field " + std::to_string(_i) + ": " + res.error()->what());
|
|
}
|
|
return;
|
|
}
|
|
read_impl<_i + 1>(_var, _err);
|
|
} else {
|
|
*_err = Error("Expected " + std::to_string(size_) + " fields, but got at least one more.");
|
|
return;
|
|
}
|
|
}
|
|
|
|
template <class T>
|
|
void call_destructor_on_array(const size_t _size, T* _ptr) const {
|
|
for (size_t i = 0; i < _size; ++i) {
|
|
if constexpr (std::is_array_v<T>) {
|
|
call_destructor_on_array(sizeof(*_ptr) / sizeof(**_ptr), *(_ptr + i));
|
|
} else if constexpr (std::is_destructible_v<T>) {
|
|
(_ptr + i)->~T();
|
|
}
|
|
}
|
|
}
|
|
|
|
template <class Target, class Source>
|
|
void move_to(Target* _t, Source* _s) const {
|
|
if constexpr (std::is_const_v<Target>) {
|
|
return move_to(const_cast<std::remove_const_t<Target>*>(_t), _s);
|
|
} else if constexpr (!internal::is_array_v<Source> && !std::is_array_v<Target>) {
|
|
::new (_t) Target(std::move(*_s));
|
|
} else if constexpr (internal::is_array_v<Source>) {
|
|
for (size_t i = 0; i < _s->arr_.size(); ++i) { move_to(&((*_t)[i]), &(_s->arr_[i])); }
|
|
} else {
|
|
for (size_t i = 0; i < _s->size(); ++i) { move_to(&((*_t)[i]), &((*_s)[i])); }
|
|
}
|
|
}
|
|
|
|
private:
|
|
/// Indicates the last field that was set.
|
|
mutable size_t i_;
|
|
|
|
/// The underlying reader.
|
|
const R* r_;
|
|
|
|
/// The underlying tuple.
|
|
TupleType* tuple_;
|
|
};
|
|
|
|
} // namespace rfl::parsing
|
|
|
|
#endif
|