src/common/reference.hpp

   1 /*
   2  * Copyright (C) 2024 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   3  *
   4  * SPDX-License-Identifier: LGPL-2.1-only
   5  *
   6  */
   7
   8 #ifndef LTTNG_REFERENCE_H
   9 #define LTTNG_REFERENCE_H
  10
  11 #include <algorithm>
  12 #include <utility>
  13
  14 namespace lttng {
  15
  16 template <typename ReferencedType, typename CustomDeleter>
  17 class non_copyable_reference {
  18 public:
  19         explicit non_copyable_reference(ReferencedType& instance) noexcept : _value(&instance)
  20         {
  21         }
  22
  23         non_copyable_reference(non_copyable_reference&& other) noexcept : _value(other._value)
  24         {
  25                 other._value = nullptr;
  26         }
  27
  28         non_copyable_reference() = delete;
  29         non_copyable_reference(const non_copyable_reference&) = delete;
  30         non_copyable_reference& operator=(non_copyable_reference&&) = delete;
  31         non_copyable_reference& operator=(const non_copyable_reference&) = delete;
  32
  33         ReferencedType& get() const noexcept
  34         {
  35                 return *_value;
  36         }
  37
  38         ReferencedType *operator->() const noexcept
  39         {
  40                 return _value;
  41         }
  42
  43         ReferencedType& operator*() const noexcept
  44         {
  45                 return *_value;
  46         }
  47
  48         ~non_copyable_reference()
  49         {
  50                 if (!_value) {
  51                         return;
  52                 }
  53
  54                 typename CustomDeleter::deleter del;
  55                 del(_value);
  56         }
  57
  58 private:
  59         ReferencedType *_value = nullptr;
  60 };
  61
  62 } /* namespace lttng */
  63
  64 #endif /* LTTNG_REFERENCE_H */