cached_event_payload.h

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#ifndef MYSQL_CSA_RELAY_LOG_CACHED_EVENT_PAYLOAD_H
#define MYSQL_CSA_RELAY_LOG_CACHED_EVENT_PAYLOAD_H
 
#include <memory>
#include "sql/binlog_reader.h"  // Default_binlog_event_allocator
#include "sql/changestreams/apply/storage/relay_log/ireader_event.h"
#include "sql/log_event.h"  // Log_event
 
namespace mysql::csa {
 
/// @brief Implementation of the IReader_event which keeps event raw
/// payload until decoded
class Cached_event_payload : public IReader_event {
 public:
  /// Is constructed using payload data/metadata and associated fde
  /// @param payload Event payload data and metadata returned by the reader
  /// @param fde Current source's fde
  Cached_event_payload(const Event_payload &payload,
                       std::shared_ptr<Log_event> fde);
 
  /// @brief Decode function, which decodes payload and returns Log event
  /// smart pointer
  /// @return Log event smart pointer
  std::shared_ptr<Log_event> decode() override;
 
  /// @brief Resets event state
  void reset(const Format_description_log_event *) override;
 
 private:
  /// Event data, owning pointer returned by the reader (legacy design)
  uint8_t *m_data;
  /// Event length
  std::size_t m_length;
  /// Information on whether to verify checksum after decoding
  bool m_verify_checksum{false};
  /// Owning pointer of the FDE base
  std::shared_ptr<Log_event> m_current_fde;
  /// Non-owning pointer to FDE
  Format_description_log_event *m_fde_ptr;
  /// @brief Allocator used to allocate event data in the reader, we use
  /// a separate object, since 'Default_binlog_event_allocator' methods do not
  /// use object state in any way
  Default_binlog_event_allocator m_allocator;
};
 
}  // namespace mysql::csa
 
#endif  // MYSQL_CSA_RELAY_LOG_CACHED_EVENT_PAYLOAD_H