ut0bool_scope_guard.h

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/** @file include/ut0bool_scope_guard.h
 The ut_bool_scope_guard class which sets boolean to true for
 the duration of scope. */
 
#ifndef ut0bool_scope_guard_h
#define ut0bool_scope_guard_h
 
namespace ut {
/** A RAII-style class, which sets a given boolean to true in constructor, and
to false in destructor, effectively making sure that it is true for the duration
of the object lifetime/scope. */
class bool_scope_guard_t {
  /** boolean to be manipulated, or nullptr if the object was moved from, or
  already destructed */
  bool *m_active;
 
 public:
  /** Creates the RAII guard which sets `active` to true for the duration of
  its lifetime.
  @param[in,out] active  the boolean which is to be manipulated */
  explicit bool_scope_guard_t(bool &active) : m_active(&active) {
    *m_active = true;
  }
  ~bool_scope_guard_t() {
    if (m_active != nullptr) {
      *m_active = false;
      m_active = nullptr;
    }
  }
  bool_scope_guard_t(bool_scope_guard_t const &) = delete;
  bool_scope_guard_t &operator=(bool_scope_guard_t const &) = delete;
  bool_scope_guard_t &operator=(bool_scope_guard_t &&) = delete;
  bool_scope_guard_t(bool_scope_guard_t &&old) {
    m_active = old.m_active;
    old.m_active = nullptr;
  }
};
}  // namespace ut
#endif /* ut0bool_scope_guard_h */