managed_event.h

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#ifndef MYSQL_CSA_MANAGED_EVENT_H
#define MYSQL_CSA_MANAGED_EVENT_H
 
#include <memory>
#include "mysql/utils/return_status.h"
#include "sql/log_event.h"  // Log_event
 
namespace mysql::csa {
 
/// @brief Managed event. For now, it contains functionality to pass memory
/// ownership between CSA threads.
class Managed_event {
 public:
  using Log_event_ptr = std::shared_ptr<Log_event>;
  /// @brief Construct
  Managed_event() = default;
  /// @brief Construct from ev
  /// @param ev Pointer to copy
  /// @param ev_owns_memory True if ev exclusively owns log event memory
  Managed_event(const Log_event_ptr &ev, bool ev_owns_memory);
  /// @brief Internal event accessor
  /// @return Reference to internal event
  Log_event_ptr &get_event();
  /// @brief Internal event accessor, const
  /// @return Reference to internal event
  const Log_event_ptr &get_event() const;
  /// @brief Marks whether this fetched event is the last event of transaction.
  void set_last_in_transaction(bool is_last);
  /// @brief Returns whether this fetched event is the last event of
  /// transaction.
  bool is_last_in_transaction() const;
  /// @brief Returns true if Managed_event manages an event, false otherwise
  explicit operator bool() const noexcept;
 
 private:
  /// @brief Internal event pointer
  Log_event_ptr m_event;
  /// @brief True if this fetched event is the transaction terminal event.
  bool m_is_last_in_transaction{false};
};
 
}  // namespace mysql::csa
 
#endif  // MYSQL_CSA_MANAGED_EVENT_H