1 //===------------------ directory_iterator.cpp ----------------------------===// 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 "filesystem" 10 #include "__config" 11 #if defined(_LIBCPP_WIN32API) 12 #define WIN32_LEAN_AND_MEAN 13 #define NOMINMAX 14 #include <windows.h> 15 #else 16 #include <dirent.h> 17 #endif 18 #include <errno.h> 19 20 #include "filesystem_common.h" 21 22 _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM 23 24 namespace detail { 25 namespace { 26 27 #if !defined(_LIBCPP_WIN32API) 28 29 #if defined(DT_BLK) 30 template <class DirEntT, class = decltype(DirEntT::d_type)> 31 static file_type get_file_type(DirEntT* ent, int) { 32 switch (ent->d_type) { 33 case DT_BLK: 34 return file_type::block; 35 case DT_CHR: 36 return file_type::character; 37 case DT_DIR: 38 return file_type::directory; 39 case DT_FIFO: 40 return file_type::fifo; 41 case DT_LNK: 42 return file_type::symlink; 43 case DT_REG: 44 return file_type::regular; 45 case DT_SOCK: 46 return file_type::socket; 47 // Unlike in lstat, hitting "unknown" here simply means that the underlying 48 // filesystem doesn't support d_type. Report is as 'none' so we correctly 49 // set the cache to empty. 50 case DT_UNKNOWN: 51 break; 52 } 53 return file_type::none; 54 } 55 #endif // defined(DT_BLK) 56 57 template <class DirEntT> 58 static file_type get_file_type(DirEntT* ent, long) { 59 return file_type::none; 60 } 61 62 static pair<string_view, file_type> posix_readdir(DIR* dir_stream, 63 error_code& ec) { 64 struct dirent* dir_entry_ptr = nullptr; 65 errno = 0; // zero errno in order to detect errors 66 ec.clear(); 67 if ((dir_entry_ptr = ::readdir(dir_stream)) == nullptr) { 68 if (errno) 69 ec = capture_errno(); 70 return {}; 71 } else { 72 return {dir_entry_ptr->d_name, get_file_type(dir_entry_ptr, 0)}; 73 } 74 } 75 #else 76 // defined(_LIBCPP_WIN32API) 77 78 static file_type get_file_type(const WIN32_FIND_DATAW& data) { 79 if (data.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT && 80 data.dwReserved0 == IO_REPARSE_TAG_SYMLINK) 81 return file_type::symlink; 82 if (data.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) 83 return file_type::directory; 84 return file_type::regular; 85 } 86 static uintmax_t get_file_size(const WIN32_FIND_DATAW& data) { 87 return (static_cast<uint64_t>(data.nFileSizeHigh) << 32) + data.nFileSizeLow; 88 } 89 static file_time_type get_write_time(const WIN32_FIND_DATAW& data) { 90 ULARGE_INTEGER tmp; 91 const FILETIME& time = data.ftLastWriteTime; 92 tmp.u.LowPart = time.dwLowDateTime; 93 tmp.u.HighPart = time.dwHighDateTime; 94 return file_time_type(file_time_type::duration(tmp.QuadPart)); 95 } 96 97 #endif 98 99 } // namespace 100 } // namespace detail 101 102 using detail::ErrorHandler; 103 104 #if defined(_LIBCPP_WIN32API) 105 class __dir_stream { 106 public: 107 __dir_stream() = delete; 108 __dir_stream& operator=(const __dir_stream&) = delete; 109 110 __dir_stream(__dir_stream&& __ds) noexcept : __stream_(__ds.__stream_), 111 __root_(move(__ds.__root_)), 112 __entry_(move(__ds.__entry_)) { 113 __ds.__stream_ = INVALID_HANDLE_VALUE; 114 } 115 116 __dir_stream(const path& root, directory_options opts, error_code& ec) 117 : __stream_(INVALID_HANDLE_VALUE), __root_(root) { 118 if (root.native().empty()) { 119 ec = make_error_code(errc::no_such_file_or_directory); 120 return; 121 } 122 __stream_ = ::FindFirstFileW((root / "*").c_str(), &__data_); 123 if (__stream_ == INVALID_HANDLE_VALUE) { 124 ec = detail::make_windows_error(GetLastError()); 125 const bool ignore_permission_denied = 126 bool(opts & directory_options::skip_permission_denied); 127 if (ignore_permission_denied && 128 ec.value() == static_cast<int>(errc::permission_denied)) 129 ec.clear(); 130 return; 131 } 132 if (!assign()) 133 advance(ec); 134 } 135 136 ~__dir_stream() noexcept { 137 if (__stream_ == INVALID_HANDLE_VALUE) 138 return; 139 close(); 140 } 141 142 bool good() const noexcept { return __stream_ != INVALID_HANDLE_VALUE; } 143 144 bool advance(error_code& ec) { 145 while (::FindNextFileW(__stream_, &__data_)) { 146 if (assign()) 147 return true; 148 } 149 close(); 150 return false; 151 } 152 153 bool assign() { 154 if (!wcscmp(__data_.cFileName, L".") || !wcscmp(__data_.cFileName, L"..")) 155 return false; 156 // FIXME: Cache more of this 157 //directory_entry::__cached_data cdata; 158 //cdata.__type_ = get_file_type(__data_); 159 //cdata.__size_ = get_file_size(__data_); 160 //cdata.__write_time_ = get_write_time(__data_); 161 __entry_.__assign_iter_entry( 162 __root_ / __data_.cFileName, 163 directory_entry::__create_iter_result(detail::get_file_type(__data_))); 164 return true; 165 } 166 167 private: 168 error_code close() noexcept { 169 error_code ec; 170 if (!::FindClose(__stream_)) 171 ec = detail::make_windows_error(GetLastError()); 172 __stream_ = INVALID_HANDLE_VALUE; 173 return ec; 174 } 175 176 HANDLE __stream_{INVALID_HANDLE_VALUE}; 177 WIN32_FIND_DATAW __data_; 178 179 public: 180 path __root_; 181 directory_entry __entry_; 182 }; 183 #else 184 class __dir_stream { 185 public: 186 __dir_stream() = delete; 187 __dir_stream& operator=(const __dir_stream&) = delete; 188 189 __dir_stream(__dir_stream&& other) noexcept : __stream_(other.__stream_), 190 __root_(move(other.__root_)), 191 __entry_(move(other.__entry_)) { 192 other.__stream_ = nullptr; 193 } 194 195 __dir_stream(const path& root, directory_options opts, error_code& ec) 196 : __stream_(nullptr), __root_(root) { 197 if ((__stream_ = ::opendir(root.c_str())) == nullptr) { 198 ec = detail::capture_errno(); 199 const bool allow_eacess = 200 bool(opts & directory_options::skip_permission_denied); 201 if (allow_eacess && ec.value() == EACCES) 202 ec.clear(); 203 return; 204 } 205 advance(ec); 206 } 207 208 ~__dir_stream() noexcept { 209 if (__stream_) 210 close(); 211 } 212 213 bool good() const noexcept { return __stream_ != nullptr; } 214 215 bool advance(error_code& ec) { 216 while (true) { 217 auto str_type_pair = detail::posix_readdir(__stream_, ec); 218 auto& str = str_type_pair.first; 219 if (str == "." || str == "..") { 220 continue; 221 } else if (ec || str.empty()) { 222 close(); 223 return false; 224 } else { 225 __entry_.__assign_iter_entry( 226 __root_ / str, 227 directory_entry::__create_iter_result(str_type_pair.second)); 228 return true; 229 } 230 } 231 } 232 233 private: 234 error_code close() noexcept { 235 error_code m_ec; 236 if (::closedir(__stream_) == -1) 237 m_ec = detail::capture_errno(); 238 __stream_ = nullptr; 239 return m_ec; 240 } 241 242 DIR* __stream_{nullptr}; 243 244 public: 245 path __root_; 246 directory_entry __entry_; 247 }; 248 #endif 249 250 // directory_iterator 251 252 directory_iterator::directory_iterator(const path& p, error_code* ec, 253 directory_options opts) { 254 ErrorHandler<void> err("directory_iterator::directory_iterator(...)", ec, &p); 255 256 error_code m_ec; 257 __imp_ = make_shared<__dir_stream>(p, opts, m_ec); 258 if (ec) 259 *ec = m_ec; 260 if (!__imp_->good()) { 261 __imp_.reset(); 262 if (m_ec) 263 err.report(m_ec); 264 } 265 } 266 267 directory_iterator& directory_iterator::__increment(error_code* ec) { 268 _LIBCPP_ASSERT(__imp_, "Attempting to increment an invalid iterator"); 269 ErrorHandler<void> err("directory_iterator::operator++()", ec); 270 271 error_code m_ec; 272 if (!__imp_->advance(m_ec)) { 273 path root = move(__imp_->__root_); 274 __imp_.reset(); 275 if (m_ec) 276 err.report(m_ec, "at root " PATH_CSTR_FMT, root.c_str()); 277 } 278 return *this; 279 } 280 281 directory_entry const& directory_iterator::__dereference() const { 282 _LIBCPP_ASSERT(__imp_, "Attempting to dereference an invalid iterator"); 283 return __imp_->__entry_; 284 } 285 286 // recursive_directory_iterator 287 288 struct recursive_directory_iterator::__shared_imp { 289 stack<__dir_stream> __stack_; 290 directory_options __options_; 291 }; 292 293 recursive_directory_iterator::recursive_directory_iterator( 294 const path& p, directory_options opt, error_code* ec) 295 : __imp_(nullptr), __rec_(true) { 296 ErrorHandler<void> err("recursive_directory_iterator", ec, &p); 297 298 error_code m_ec; 299 __dir_stream new_s(p, opt, m_ec); 300 if (m_ec) 301 err.report(m_ec); 302 if (m_ec || !new_s.good()) 303 return; 304 305 __imp_ = make_shared<__shared_imp>(); 306 __imp_->__options_ = opt; 307 __imp_->__stack_.push(move(new_s)); 308 } 309 310 void recursive_directory_iterator::__pop(error_code* ec) { 311 _LIBCPP_ASSERT(__imp_, "Popping the end iterator"); 312 if (ec) 313 ec->clear(); 314 __imp_->__stack_.pop(); 315 if (__imp_->__stack_.size() == 0) 316 __imp_.reset(); 317 else 318 __advance(ec); 319 } 320 321 directory_options recursive_directory_iterator::options() const { 322 return __imp_->__options_; 323 } 324 325 int recursive_directory_iterator::depth() const { 326 return __imp_->__stack_.size() - 1; 327 } 328 329 const directory_entry& recursive_directory_iterator::__dereference() const { 330 return __imp_->__stack_.top().__entry_; 331 } 332 333 recursive_directory_iterator& 334 recursive_directory_iterator::__increment(error_code* ec) { 335 if (ec) 336 ec->clear(); 337 if (recursion_pending()) { 338 if (__try_recursion(ec) || (ec && *ec)) 339 return *this; 340 } 341 __rec_ = true; 342 __advance(ec); 343 return *this; 344 } 345 346 void recursive_directory_iterator::__advance(error_code* ec) { 347 ErrorHandler<void> err("recursive_directory_iterator::operator++()", ec); 348 349 const directory_iterator end_it; 350 auto& stack = __imp_->__stack_; 351 error_code m_ec; 352 while (stack.size() > 0) { 353 if (stack.top().advance(m_ec)) 354 return; 355 if (m_ec) 356 break; 357 stack.pop(); 358 } 359 360 if (m_ec) { 361 path root = move(stack.top().__root_); 362 __imp_.reset(); 363 err.report(m_ec, "at root " PATH_CSTR_FMT, root.c_str()); 364 } else { 365 __imp_.reset(); 366 } 367 } 368 369 bool recursive_directory_iterator::__try_recursion(error_code* ec) { 370 ErrorHandler<void> err("recursive_directory_iterator::operator++()", ec); 371 372 bool rec_sym = bool(options() & directory_options::follow_directory_symlink); 373 374 auto& curr_it = __imp_->__stack_.top(); 375 376 bool skip_rec = false; 377 error_code m_ec; 378 if (!rec_sym) { 379 file_status st(curr_it.__entry_.__get_sym_ft(&m_ec)); 380 if (m_ec && status_known(st)) 381 m_ec.clear(); 382 if (m_ec || is_symlink(st) || !is_directory(st)) 383 skip_rec = true; 384 } else { 385 file_status st(curr_it.__entry_.__get_ft(&m_ec)); 386 if (m_ec && status_known(st)) 387 m_ec.clear(); 388 if (m_ec || !is_directory(st)) 389 skip_rec = true; 390 } 391 392 if (!skip_rec) { 393 __dir_stream new_it(curr_it.__entry_.path(), __imp_->__options_, m_ec); 394 if (new_it.good()) { 395 __imp_->__stack_.push(move(new_it)); 396 return true; 397 } 398 } 399 if (m_ec) { 400 const bool allow_eacess = 401 bool(__imp_->__options_ & directory_options::skip_permission_denied); 402 if (m_ec.value() == EACCES && allow_eacess) { 403 if (ec) 404 ec->clear(); 405 } else { 406 path at_ent = move(curr_it.__entry_.__p_); 407 __imp_.reset(); 408 err.report(m_ec, "attempting recursion into " PATH_CSTR_FMT, 409 at_ent.c_str()); 410 } 411 } 412 return false; 413 } 414 415 _LIBCPP_END_NAMESPACE_FILESYSTEM 416