tag_plain.h

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#ifndef MYSQL_GTID_TAG_PLAIN_H
#define MYSQL_GTID_TAG_PLAIN_H
 
#include <array>
#include <cstring>
#include <memory>
#include <string>
 
#include "mysql/gtid/gtid_constants.h"  // tag_max_length
 
/// @addtogroup GroupLibsMysqlGtid
/// @{
 
namespace mysql::gtid {
 
class Tag;
 
/// @brief Tag representation so that:
/// - Tag_plain is trivial
/// - Tag_plain is standard layout
/// Therefore, a Tag_plain object is not empty by default! Use clear() or
/// brace-enclosed initializer list to create an empty tag.
/// Tag_plain must be a POD because it is used in Gtid_specification
struct Tag_plain {
  /// @brief Default ctor
  Tag_plain() = default;
  /// @brief Construct from tag object
  /// @param tag tag to copy
  explicit Tag_plain(const Tag &tag);
 
  /// @brief Clear this tag
  void clear();
 
  /// @brief Checks whether tag is defined
  /// @retval true Tag is defined
  /// @retval false Tag is empty
  bool is_defined() const;
 
  /// @brief Obtains tag length
  /// @return tag length
  std::size_t length() const;
 
  /// @brief Copies internal tag into a given buffer
  /// @param[in,out] buf Buffer, needs to be pre-allocated
  /// @return Number of bytes written into the buffer
  std::size_t to_string(char *buf) const;
 
  /// @brief Sets internal data to match a given pattern
  /// @param[in] tag Pattern to copy from
  void set(const Tag &tag);
 
  /// @brief Internal data accessor (for encoding)
  const unsigned char *data() const;
 
 private:
  /// null terminated tag representation
  unsigned char m_data[tag_max_length + 1];
};
 
static_assert(std::is_trivial_v<Tag_plain>);
static_assert(std::is_standard_layout_v<Tag_plain>);
 
}  // namespace mysql::gtid
 
/// @}
 
#endif  // MYSQL_GTID_TAG_PLAIN_H