log0sys_var_handler.h

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#pragma once
 
#include <string_view>
 
#include "ha0sys_var_handler_interface.h"
 
namespace ib::redo {
class Handler;
/** This class implements the handling of redo log related system variables */
class Sys_var_handler final : public Sys_var_handler_interface {
 public:
  Sys_var_handler(Handler &handler) : m_handler{handler} {}
  ~Sys_var_handler() override;
 
  [[nodiscard]] bool update_var(THD *thd, std::string_view name,
                                uint64_t new_value) override;
 
  [[nodiscard]] bool update_var(THD *thd, std::string_view name,
                                bool new_value) override;
 
 private:
  /** Update the innodb_log_buffer_size system variable */
  [[nodiscard]] bool buffer_size_update(uint64_t value);
 
  /** Update the innodb_log_writer_threads system variable */
  void writer_threads_update(bool value);
 
  /** Update the innodb_redo_log_capacity system variable */
  [[nodiscard]] bool capacity_update(THD *thd, std::string_view var_name,
                                     uint64_t value);
 
  [[nodiscard]] bool log_write_ahead_size_update(THD *thd,
                                                 std::string_view var_name,
                                                 uint64_t value);
  Handler &m_handler;
};
}  // namespace ib::redo