xref: /llvm-project/libcxx/include/__filesystem/directory_iterator.h (revision c6f3b7bcd0596d30f8dabecdfb9e44f9a07b6e4c)
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___FILESYSTEM_DIRECTORY_ITERATOR_H
11 #define _LIBCPP___FILESYSTEM_DIRECTORY_ITERATOR_H
12 
13 #include <__assert>
14 #include <__config>
15 #include <__filesystem/directory_entry.h>
16 #include <__filesystem/directory_options.h>
17 #include <__filesystem/path.h>
18 #include <__iterator/default_sentinel.h>
19 #include <__iterator/iterator_traits.h>
20 #include <__memory/shared_ptr.h>
21 #include <__ranges/enable_borrowed_range.h>
22 #include <__ranges/enable_view.h>
23 #include <__system_error/error_code.h>
24 #include <__utility/move.h>
25 
26 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
27 #  pragma GCC system_header
28 #endif
29 
30 _LIBCPP_PUSH_MACROS
31 #include <__undef_macros>
32 
33 #if _LIBCPP_STD_VER >= 17 && _LIBCPP_HAS_FILESYSTEM
34 
35 _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
36 
37 _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_PUSH
38 
39 class _LIBCPP_HIDDEN __dir_stream;
40 class directory_iterator {
41 public:
42   typedef directory_entry value_type;
43   typedef ptrdiff_t difference_type;
44   typedef value_type const* pointer;
45   typedef value_type const& reference;
46   typedef input_iterator_tag iterator_category;
47 
48 public:
49   // ctor & dtor
50   _LIBCPP_HIDE_FROM_ABI directory_iterator() noexcept {}
51 
52   _LIBCPP_HIDE_FROM_ABI explicit directory_iterator(const path& __p) : directory_iterator(__p, nullptr) {}
53 
54   _LIBCPP_HIDE_FROM_ABI directory_iterator(const path& __p, directory_options __opts)
55       : directory_iterator(__p, nullptr, __opts) {}
56 
57   _LIBCPP_HIDE_FROM_ABI directory_iterator(const path& __p, error_code& __ec) : directory_iterator(__p, &__ec) {}
58 
59   _LIBCPP_HIDE_FROM_ABI directory_iterator(const path& __p, directory_options __opts, error_code& __ec)
60       : directory_iterator(__p, &__ec, __opts) {}
61 
62   _LIBCPP_HIDE_FROM_ABI directory_iterator(const directory_iterator&)            = default;
63   _LIBCPP_HIDE_FROM_ABI directory_iterator(directory_iterator&&)                 = default;
64   _LIBCPP_HIDE_FROM_ABI directory_iterator& operator=(const directory_iterator&) = default;
65 
66   _LIBCPP_HIDE_FROM_ABI directory_iterator& operator=(directory_iterator&& __o) noexcept {
67     // non-default implementation provided to support self-move assign.
68     if (this != &__o) {
69       __imp_ = std::move(__o.__imp_);
70     }
71     return *this;
72   }
73 
74   _LIBCPP_HIDE_FROM_ABI ~directory_iterator() = default;
75 
76   _LIBCPP_HIDE_FROM_ABI const directory_entry& operator*() const {
77     // Note: this check duplicates a check in `__dereference()`.
78     _LIBCPP_ASSERT_NON_NULL(__imp_, "The end iterator cannot be dereferenced");
79     return __dereference();
80   }
81 
82   _LIBCPP_HIDE_FROM_ABI const directory_entry* operator->() const { return &**this; }
83 
84   _LIBCPP_HIDE_FROM_ABI directory_iterator& operator++() { return __increment(); }
85 
86   _LIBCPP_HIDE_FROM_ABI __dir_element_proxy operator++(int) {
87     __dir_element_proxy __p(**this);
88     __increment();
89     return __p;
90   }
91 
92   _LIBCPP_HIDE_FROM_ABI directory_iterator& increment(error_code& __ec) { return __increment(&__ec); }
93 
94 #  if _LIBCPP_STD_VER >= 20
95 
96   _LIBCPP_HIDE_FROM_ABI bool operator==(default_sentinel_t) const noexcept { return *this == directory_iterator(); }
97 
98 #  endif
99 
100 private:
101   inline _LIBCPP_HIDE_FROM_ABI friend bool
102   operator==(const directory_iterator& __lhs, const directory_iterator& __rhs) noexcept;
103 
104   // construct the dir_stream
105   _LIBCPP_EXPORTED_FROM_ABI directory_iterator(const path&, error_code*, directory_options = directory_options::none);
106 
107   _LIBCPP_EXPORTED_FROM_ABI directory_iterator& __increment(error_code* __ec = nullptr);
108 
109   _LIBCPP_EXPORTED_FROM_ABI const directory_entry& __dereference() const;
110 
111 private:
112   shared_ptr<__dir_stream> __imp_;
113 };
114 
115 inline _LIBCPP_HIDE_FROM_ABI bool
116 operator==(const directory_iterator& __lhs, const directory_iterator& __rhs) noexcept {
117   return __lhs.__imp_ == __rhs.__imp_;
118 }
119 
120 inline _LIBCPP_HIDE_FROM_ABI bool
121 operator!=(const directory_iterator& __lhs, const directory_iterator& __rhs) noexcept {
122   return !(__lhs == __rhs);
123 }
124 
125 // enable directory_iterator range-based for statements
126 inline _LIBCPP_HIDE_FROM_ABI directory_iterator begin(directory_iterator __iter) noexcept { return __iter; }
127 
128 inline _LIBCPP_HIDE_FROM_ABI directory_iterator end(directory_iterator) noexcept { return directory_iterator(); }
129 
130 _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY_POP
131 
132 _LIBCPP_END_NAMESPACE_FILESYSTEM
133 
134 #  if _LIBCPP_STD_VER >= 20
135 
136 template <>
137 _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY inline constexpr bool
138     std::ranges::enable_borrowed_range<std::filesystem::directory_iterator> = true;
139 
140 template <>
141 _LIBCPP_AVAILABILITY_FILESYSTEM_LIBRARY inline constexpr bool
142     std::ranges::enable_view<std::filesystem::directory_iterator> = true;
143 
144 #  endif // _LIBCPP_STD_VER >= 20
145 
146 #endif // _LIBCPP_STD_VER >= 17 && _LIBCPP_HAS_FILESYSTEM
147 
148 _LIBCPP_POP_MACROS
149 
150 #endif // _LIBCPP___FILESYSTEM_DIRECTORY_ITERATOR_H
151