1// -*- C++ -*-
 2//===----------------------------------------------------------------------===//
 3//
 4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 5// See https://llvm.org/LICENSE.txt for license information.
 6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 7//
 8//===----------------------------------------------------------------------===//
 9
10#ifndef _LIBCPP___UTILITY_SCOPE_GUARD_H
11#define _LIBCPP___UTILITY_SCOPE_GUARD_H
12
13#include <__config>
14#include <__utility/move.h>
15
16#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
17#  pragma GCC system_header
18#endif
19
20_LIBCPP_PUSH_MACROS
21#include <__undef_macros>
22
23_LIBCPP_BEGIN_NAMESPACE_STD
24
25template <class _Func>
26class __scope_guard {
27  _Func __func_;
28
29public:
30  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR explicit __scope_guard(_Func __func) : __func_(std::move(__func)) {}
31  _LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX20 ~__scope_guard() { __func_(); }
32
33  __scope_guard(const __scope_guard&)            = delete;
34  __scope_guard& operator=(const __scope_guard&) = delete;
35  __scope_guard& operator=(__scope_guard&&)      = delete;
36
37// C++14 doesn't have mandatory RVO, so we have to provide a declaration even though no compiler will ever generate
38// a call to the move constructor.
39#if _LIBCPP_STD_VER <= 14
40  __scope_guard(__scope_guard&&);
41#else
42  __scope_guard(__scope_guard&&) = delete;
43#endif
44};
45
46template <class _Func>
47_LIBCPP_HIDE_FROM_ABI _LIBCPP_CONSTEXPR_SINCE_CXX14 __scope_guard<_Func> __make_scope_guard(_Func __func) {
48  return __scope_guard<_Func>(std::move(__func));
49}
50
51_LIBCPP_END_NAMESPACE_STD
52
53_LIBCPP_POP_MACROS
54
55#endif // _LIBCPP___UTILITY_SCOPE_GUARD_H