PMDK C++ bindings  1.9.1
This is the C++ bindings documentation for PMDK's libpmemobj.
temp_value.hpp
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32 
38 #ifndef LIBPMEMOBJ_CPP_TEMP_VALUE_HPP
39 #define LIBPMEMOBJ_CPP_TEMP_VALUE_HPP
40 
42 
43 namespace pmem
44 {
45 
46 namespace detail
47 {
48 
54 #ifndef LIBPMEMOBJ_CPP_MAX_STACK_ALLOC_SIZE
55 #define LIBPMEMOBJ_CPP_MAX_STACK_ALLOC_SIZE 64 * (1 << 10)
56 #endif
57 
63 template <typename T, bool NoExcept, typename Enable = void>
64 struct temp_value;
65 
71 template <typename T, bool NoExcept>
72 struct temp_value<
73  T, NoExcept,
74  typename std::enable_if<NoExcept &&
75  (sizeof(T) <
76  LIBPMEMOBJ_CPP_MAX_STACK_ALLOC_SIZE)>::type> {
77  template <typename... Args>
78  temp_value(Args &&... args) noexcept : t(std::forward<Args>(args)...)
79  {
80  }
81 
82  T &
83  get() noexcept
84  {
85  return t;
86  }
87 
88  T t;
89 };
90 
96 template <typename T, bool NoExcept>
97 struct temp_value<
98  T, NoExcept,
99  typename std::enable_if<!NoExcept ||
100  (sizeof(T) >=
101  LIBPMEMOBJ_CPP_MAX_STACK_ALLOC_SIZE)>::type> {
102  template <typename... Args>
103  temp_value(Args &&... args)
104  {
105  ptr = pmem::obj::make_persistent<T>(
106  std::forward<Args>(args)...);
107  }
108 
109  ~temp_value()
110  {
111  pmem::obj::delete_persistent<T>(ptr);
112  }
113 
114  T &
115  get()
116  {
117  return *ptr;
118  }
119 
121 };
122 
123 } /* namespace detail */
124 
125 } /* namespace pmem */
126 
127 #endif /* LIBPMEMOBJ_CPP_TEMP_VALUE_HPP */
pmem
Persistent memory namespace.
Definition: allocation_flag.hpp:44
make_persistent.hpp
Persistent_ptr transactional allocation functions for objects.
pmem::detail::temp_value
Template class for caching objects based on constructor's variadic template arguments and LIBPMEMOBJ_...
Definition: temp_value.hpp:64
pmem::obj::persistent_ptr
Persistent pointer class.
Definition: persistent_ptr.hpp:212
pmem::obj::get
T & get(pmem::obj::array< T, N > &a)
Non-member get function.
Definition: array.hpp:923