libstdc++
source_location
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1 // <source_location> -*- C++ -*-
2 
3 // Copyright (C) 2020-2022 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 /** @file include/source_location
26  * This is a Standard C++ Library header.
27  */
28 
29 #ifndef _GLIBCXX_SRCLOC
30 #define _GLIBCXX_SRCLOC 1
31 
32 #if __cplusplus > 201703L && __has_builtin(__builtin_source_location)
33 #include <bits/c++config.h>
34 
35 namespace std
36 {
37 _GLIBCXX_BEGIN_NAMESPACE_VERSION
38 
39 #define __cpp_lib_source_location 201907L
40 
41  /// A class that describes a location in source code.
42  struct source_location
43  {
44  private:
45  using uint_least32_t = __UINT_LEAST32_TYPE__;
46  struct __impl
47  {
48  const char* _M_file_name;
49  const char* _M_function_name;
50  unsigned _M_line;
51  unsigned _M_column;
52  };
53  using __builtin_ret_type = decltype(__builtin_source_location());
54 
55  public:
56 
57  // [support.srcloc.cons], creation
58  static consteval source_location
59  current(__builtin_ret_type __p = __builtin_source_location()) noexcept
60  {
61  source_location __ret;
62  __ret._M_impl = static_cast <const __impl*>(__p);
63  return __ret;
64  }
65 
66  constexpr source_location() noexcept { }
67 
68  // [support.srcloc.obs], observers
69  constexpr uint_least32_t
70  line() const noexcept
71  { return _M_impl ? _M_impl->_M_line : 0u; }
72 
73  constexpr uint_least32_t
74  column() const noexcept
75  { return _M_impl ? _M_impl->_M_column : 0u; }
76 
77  constexpr const char*
78  file_name() const noexcept
79  { return _M_impl ? _M_impl->_M_file_name : ""; }
80 
81  constexpr const char*
82  function_name() const noexcept
83  { return _M_impl ? _M_impl->_M_function_name : ""; }
84 
85  private:
86  const __impl* _M_impl = nullptr;
87  };
88 
89 _GLIBCXX_END_NAMESPACE_VERSION
90 } // namespace std
91 #endif // C++20 && __builtin_source_location
92 #endif // _GLIBCXX_SRCLOC