field_wrapper.h

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#ifndef MYSQL_SERIALIZATION_FIELD_WRAPPER_H
#define MYSQL_SERIALIZATION_FIELD_WRAPPER_H
 
#include "mysql/serialization/field_definition.h"
#include "mysql/serialization/serialization_types.h"
 
/// @file
/// Experimental API header
 
/// @addtogroup GroupLibsMysqlSerialization
/// @{
 
namespace mysql::serialization {
 
/// @brief Wrapper for fields to hold field reference and
/// user-defined, compile-time field size
/// @note This is created in order to pass information about field size
/// to the Archive
template <typename Field_type, Field_size defined_field_size>
class Field_wrapper {
 public:
  using value_type = Field_type;
  static constexpr Field_size value_size = defined_field_size;
  using Field_ref_type = Field_type &;
  using Field_ref_wrapper_type = std::reference_wrapper<Field_type>;
  /// @brief Constructor
  /// @param field_reference Reference to field
  Field_wrapper(Field_type &field_reference) : m_ref(field_reference) {}
 
  /// @brief field bare reference accessor
  /// @returns Reference to Field_type object
  Field_ref_type get() { return m_ref.get(); }
 
 private:
  Field_ref_wrapper_type m_ref;  ///< Internal reference
};
 
/// @brief Wrapper for fields to hold field reference and defined by the
/// user compile time size of the field
/// @note This is created in order to pass information about field size
/// to the Archive
template <typename Field_type, Field_size defined_field_size>
class Field_wrapper<const Field_type, defined_field_size> {
 public:
  using value_type = Field_type;
  static constexpr Field_size value_size = defined_field_size;
  using Field_ref_type = const Field_type &;
  using Field_ref_wrapper_type = std::reference_wrapper<const Field_type>;
  /// @brief Constructor
  /// @param field_reference Reference to field
  Field_wrapper(Field_ref_type field_reference) : m_ref(field_reference) {}
 
  /// @brief field bare reference accessor
  /// @returns Reference to Field_type object
  Field_ref_type get() const { return m_ref.get(); }
 
 private:
  Field_ref_wrapper_type m_ref;  ///< Internal reference
};
 
template <typename Field_type>
auto create_varlen_field_wrapper(Field_type &field_reference) {
  return Field_wrapper<Field_type, 0>(field_reference);
}
 
}  // namespace mysql::serialization
 
/// @}
 
#endif  // MYSQL_SERIALIZATION_FIELD_WRAPPER_H