1//===----------------------------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include <__assert>
10#include <__config>
11#include <__memory/shared_ptr.h>
12#include <errno.h>
13#include <filesystem>
14#include <stack>
15#include <utility>
16
17#include "error.h"
18#include "file_descriptor.h"
19
20#if defined(_LIBCPP_WIN32API)
21# define WIN32_LEAN_AND_MEAN
22# define NOMINMAX
23# include <windows.h>
24#else
25# include <dirent.h> // for DIR & friends
26#endif
27
28_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
29
30using detail::ErrorHandler;
31
32#if defined(_LIBCPP_WIN32API)
33class __dir_stream {
34public:
35 __dir_stream() = delete;
36 __dir_stream& operator=(const __dir_stream&) = delete;
37
38 __dir_stream(__dir_stream&& __ds) noexcept
39 : __stream_(__ds.__stream_), __root_(std::move(__ds.__root_)), __entry_(std::move(__ds.__entry_)) {
40 __ds.__stream_ = INVALID_HANDLE_VALUE;
41 }
42
43 __dir_stream(const path& root, directory_options opts, error_code& ec)
44 : __stream_(INVALID_HANDLE_VALUE), __root_(root) {
45 if (root.native().empty()) {
46 ec = make_error_code(errc::no_such_file_or_directory);
47 return;
48 }
49 __stream_ = ::FindFirstFileW((root / "*").c_str(), &__data_);
50 if (__stream_ == INVALID_HANDLE_VALUE) {
51 ec = detail::get_last_error();
52 const bool ignore_permission_denied = bool(opts & directory_options::skip_permission_denied);
53 if (ignore_permission_denied && ec == errc::permission_denied)
54 ec.clear();
55 return;
56 }
57 if (!assign())
58 advance(ec);
59 }
60
61 ~__dir_stream() noexcept {
62 if (__stream_ == INVALID_HANDLE_VALUE)
63 return;
64 close();
65 }
66
67 bool good() const noexcept { return __stream_ != INVALID_HANDLE_VALUE; }
68
69 bool advance(error_code& ec) {
70 while (::FindNextFileW(__stream_, &__data_)) {
71 if (assign())
72 return true;
73 }
74 close();
75 return false;
76 }
77
78 bool assign() {
79 if (!wcscmp(__data_.cFileName, L".") || !wcscmp(__data_.cFileName, L".."))
80 return false;
81 __entry_.__assign_iter_entry(
82 __root_ / __data_.cFileName,
83 directory_entry::__create_iter_cached_result(
84 detail::get_file_type(__data_),
85 detail::get_file_size(__data_),
86 detail::get_file_perm(__data_),
87 detail::get_write_time(__data_)));
88 return true;
89 }
90
91private:
92 error_code close() noexcept {
93 error_code ec;
94 if (!::FindClose(__stream_))
95 ec = detail::get_last_error();
96 __stream_ = INVALID_HANDLE_VALUE;
97 return ec;
98 }
99
100 HANDLE __stream_{INVALID_HANDLE_VALUE};
101 WIN32_FIND_DATAW __data_;
102
103public:
104 path __root_;
105 directory_entry __entry_;
106};
107#else
108class __dir_stream {
109public:
110 __dir_stream() = delete;
111 __dir_stream& operator=(const __dir_stream&) = delete;
112
113 __dir_stream(__dir_stream&& other) noexcept
114 : __stream_(other.__stream_), __root_(std::move(other.__root_)), __entry_(std::move(other.__entry_)) {
115 other.__stream_ = nullptr;
116 }
117
118 __dir_stream(const path& root, directory_options opts, error_code& ec) : __stream_(nullptr), __root_(root) {
119 if ((__stream_ = ::opendir(name: root.c_str())) == nullptr) {
120 ec = detail::capture_errno();
121 const bool allow_eacces = bool(opts & directory_options::skip_permission_denied);
122 if (allow_eacces && ec == errc::permission_denied)
123 ec.clear();
124 return;
125 }
126 advance(ec);
127 }
128
129 ~__dir_stream() noexcept {
130 if (__stream_)
131 close();
132 }
133
134 bool good() const noexcept { return __stream_ != nullptr; }
135
136 bool advance(error_code& ec) {
137 while (true) {
138 auto str_type_pair = detail::posix_readdir(dir_stream: __stream_, ec);
139 auto& str = str_type_pair.first;
140 if (str == "." || str == "..") {
141 continue;
142 } else if (ec || str.empty()) {
143 close();
144 return false;
145 } else {
146 __entry_.__assign_iter_entry(p: __root_ / str, dt: directory_entry::__create_iter_result(ft: str_type_pair.second));
147 return true;
148 }
149 }
150 }
151
152private:
153 error_code close() noexcept {
154 error_code m_ec;
155 if (::closedir(dirp: __stream_) == -1)
156 m_ec = detail::capture_errno();
157 __stream_ = nullptr;
158 return m_ec;
159 }
160
161 DIR* __stream_{nullptr};
162
163public:
164 path __root_;
165 directory_entry __entry_;
166};
167#endif
168
169// directory_iterator
170
171directory_iterator::directory_iterator(const path& p, error_code* ec, directory_options opts) {
172 ErrorHandler<void> err("directory_iterator::directory_iterator(...)", ec, &p);
173
174 error_code m_ec;
175 __imp_ = make_shared<__dir_stream>(args: p, args&: opts, args&: m_ec);
176 if (ec)
177 *ec = m_ec;
178 if (!__imp_->good()) {
179 __imp_.reset();
180 if (m_ec)
181 err.report(ec: m_ec);
182 }
183}
184
185directory_iterator& directory_iterator::__increment(error_code* ec) {
186 _LIBCPP_ASSERT_NON_NULL(__imp_ != nullptr, "Attempting to increment an invalid iterator");
187 ErrorHandler<void> err("directory_iterator::operator++()", ec);
188
189 error_code m_ec;
190 if (!__imp_->advance(ec&: m_ec)) {
191 path root = std::move(__imp_->__root_);
192 __imp_.reset();
193 if (m_ec)
194 err.report(ec: m_ec, msg: "at root " PATH_CSTR_FMT, root.c_str());
195 }
196 return *this;
197}
198
199directory_entry const& directory_iterator::__dereference() const {
200 _LIBCPP_ASSERT_NON_NULL(__imp_ != nullptr, "Attempting to dereference an invalid iterator");
201 return __imp_->__entry_;
202}
203
204// recursive_directory_iterator
205
206struct recursive_directory_iterator::__shared_imp {
207 stack<__dir_stream> __stack_;
208 directory_options __options_;
209};
210
211recursive_directory_iterator::recursive_directory_iterator(const path& p, directory_options opt, error_code* ec)
212 : __imp_(nullptr), __rec_(true) {
213 ErrorHandler<void> err("recursive_directory_iterator", ec, &p);
214
215 error_code m_ec;
216 __dir_stream new_s(p, opt, m_ec);
217 if (m_ec)
218 err.report(ec: m_ec);
219 if (m_ec || !new_s.good())
220 return;
221
222 __imp_ = make_shared<__shared_imp>();
223 __imp_->__options_ = opt;
224 __imp_->__stack_.push(v: std::move(new_s));
225}
226
227void recursive_directory_iterator::__pop(error_code* ec) {
228 _LIBCPP_ASSERT_NON_NULL(__imp_ != nullptr, "Popping the end iterator");
229 if (ec)
230 ec->clear();
231 __imp_->__stack_.pop();
232 if (__imp_->__stack_.size() == 0)
233 __imp_.reset();
234 else
235 __advance(ec: ec);
236}
237
238directory_options recursive_directory_iterator::options() const { return __imp_->__options_; }
239
240int recursive_directory_iterator::depth() const { return __imp_->__stack_.size() - 1; }
241
242const directory_entry& recursive_directory_iterator::__dereference() const { return __imp_->__stack_.top().__entry_; }
243
244recursive_directory_iterator& recursive_directory_iterator::__increment(error_code* ec) {
245 if (ec)
246 ec->clear();
247 if (recursion_pending()) {
248 if (__try_recursion(ec: ec) || (ec && *ec))
249 return *this;
250 }
251 __rec_ = true;
252 __advance(ec: ec);
253 return *this;
254}
255
256void recursive_directory_iterator::__advance(error_code* ec) {
257 ErrorHandler<void> err("recursive_directory_iterator::operator++()", ec);
258
259 const directory_iterator end_it;
260 auto& stack = __imp_->__stack_;
261 error_code m_ec;
262 while (stack.size() > 0) {
263 if (stack.top().advance(ec&: m_ec))
264 return;
265 if (m_ec)
266 break;
267 stack.pop();
268 }
269
270 if (m_ec) {
271 path root = std::move(stack.top().__root_);
272 __imp_.reset();
273 err.report(ec: m_ec, msg: "at root " PATH_CSTR_FMT, root.c_str());
274 } else {
275 __imp_.reset();
276 }
277}
278
279bool recursive_directory_iterator::__try_recursion(error_code* ec) {
280 ErrorHandler<void> err("recursive_directory_iterator::operator++()", ec);
281
282 bool rec_sym = bool(options() & directory_options::follow_directory_symlink);
283
284 auto& curr_it = __imp_->__stack_.top();
285
286 bool skip_rec = false;
287 error_code m_ec;
288 if (!rec_sym) {
289 file_status st(curr_it.__entry_.__get_sym_ft(ec: &m_ec));
290 if (m_ec && status_known(s: st))
291 m_ec.clear();
292 if (m_ec || is_symlink(s: st) || !is_directory(s: st))
293 skip_rec = true;
294 } else {
295 file_status st(curr_it.__entry_.__get_ft(ec: &m_ec));
296 if (m_ec && status_known(s: st))
297 m_ec.clear();
298 if (m_ec || !is_directory(s: st))
299 skip_rec = true;
300 }
301
302 if (!skip_rec) {
303 __dir_stream new_it(curr_it.__entry_.path(), __imp_->__options_, m_ec);
304 if (new_it.good()) {
305 __imp_->__stack_.push(v: std::move(new_it));
306 return true;
307 }
308 }
309 if (m_ec) {
310 const bool allow_eacess = bool(__imp_->__options_ & directory_options::skip_permission_denied);
311 if (m_ec == errc::permission_denied && allow_eacess) {
312 if (ec)
313 ec->clear();
314 } else {
315 path at_ent = std::move(curr_it.__entry_.__p_);
316 __imp_.reset();
317 err.report(ec: m_ec, msg: "attempting recursion into " PATH_CSTR_FMT, at_ent.c_str());
318 }
319 }
320 return false;
321}
322
323_LIBCPP_END_NAMESPACE_FILESYSTEM
324