lock_guard_object.h

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#ifndef MYSQL_CSA_LOCK_OBJECT_GUARD_H
#define MYSQL_CSA_LOCK_OBJECT_GUARD_H
 
#include <mysql/psi/mysql_mutex.h>
#include <mysql/psi/mysql_rwlock.h>
#include "my_sys.h"
#include "mysql/service_mysql_alloc.h"
 
#include "mysql/scheduler/logger_stream.h"
#include "sql/changestreams/apply/psi/psi.h"
#include "sql/changestreams/apply/util/initable.h"
 
namespace mysql::csa {
 
/// @brief Scope guard to unlock an object
///
/// Assumes the object is locked upon construction and calls unlock() on
/// destruction unless reset() is called.
/// @tparam Type of the object to unlock
template <typename Type>
class Lock_guard_object {
 public:
  /// @brief Unlocks the object if the locked flag is set and then resets the
  /// flag.
  void reset() {
    if (locked) m_obj->unlock();
    locked = false;
  }
  /// @brief Destructor that unlocks if not unlocked
  ~Lock_guard_object() { reset(); }
  /// @brief Constructor
  /// @param module Pointer to the object to unlock
  Lock_guard_object(Type *module) : m_obj(module) {}
 
 protected:
  /// @brief Locked object pointer
  Type *m_obj;
  /// @brief Lock flag
  bool locked{true};
};
 
}  // namespace mysql::csa
 
#endif  // MYSQL_CSA_LOCK_OBJECT_GUARD_H