ha0sys_var_handler_interface.h

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/* Copyright (c) 2023, 2026, Oracle and/or its affiliates.
 
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*/
 
#pragma once
 
#include <cstdint>
#include <string_view>
 
class THD;  // Forward declaration
namespace ib {
/* This interface provides methods to handle the system variables related
configurations. The goal is to enable multiple implementation by various
sub systems within Innodb. A Subsystem may have different implementations
to handle the system variables related to it.*/
class Sys_var_handler_interface {
 public:
  /** Default destructor */
  virtual ~Sys_var_handler_interface() = default;
 
  /** Update the system variable to the new value.
 
  @param[in] thd  THD object, may be used to print warning
  @param[in] name The system variable name
  @param[in] new_value  The value to be updated
  @return true  System variable was updated successfully
  @return false Otherwise*/
  [[nodiscard]] virtual bool update_var(THD *thd [[maybe_unused]],
                                        std::string_view name,
                                        uint64_t new_value) = 0;
 
  /** Update the system variable to the new value.
 
  @param[in] thd  THD object, may be used to print warning
  @param[in] name The system variable name
  @param[in] new_value  The value to be updated
  @return true  System variable was updated successfully
  @return false Otherwise*/
  [[nodiscard]] virtual bool update_var(THD *thd [[maybe_unused]],
                                        std::string_view name,
                                        bool new_value) = 0;
};
}  // namespace ib