mutex_wrapper.h

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#ifndef MYSQL_CONCURRENCY_MUTEX_WRAPPER_H
#define MYSQL_CONCURRENCY_MUTEX_WRAPPER_H
 
#include "mysql/psi/mysql_mutex.h"
 
namespace mysql::concurrency {
 
/// @brief MySQL wrapper for a mutex, template which may be specialized with
/// a specific implementation of a mutex, e.g. MySQL mutex, and satisfying
/// the following requirements:
///  - Lockable
///  - Destructible
///  - not copyable
///  - not movable
class Mutex_wrapper {
 public:
  Mutex_wrapper(PSI_mutex_key key);
  ~Mutex_wrapper();
 
  // Disable copy-move semantics
  Mutex_wrapper(const Mutex_wrapper &) = delete;
  Mutex_wrapper(Mutex_wrapper &&) = delete;
  Mutex_wrapper &operator=(const Mutex_wrapper &src) = delete;
  Mutex_wrapper &operator=(Mutex_wrapper &&src) = delete;
 
  /// @brief Acquire a lock, blocks access to a critical section until "unlock"
  /// is called
  void lock() noexcept;
 
  /// Non-blocking try-lock operation
  /// @retval true Lock has been acquired
  /// @retval false Lock has NOT been acquired
  bool try_lock() noexcept;
 
  /// @brief Unblocks access to a critical section for other threads
  void unlock();
 
  /// @brief Returns the native handle of the mutex
  /// @return Reference to the underlying mysql_mutex_t object
  decltype(auto) native_handle() { return &m_mutex; }
 
 protected:
  mysql_mutex_t m_mutex;
};
 
}  // namespace mysql::concurrency
 
#endif  // MYSQL_CONCURRENCY_MUTEX_WRAPPER_H