1  // Filesystem directory utilities -*- C++ -*-
       2  
       3  // Copyright (C) 2014-2023 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/bits/fs_dir.h
      26   *  This is an internal header file, included by other library headers.
      27   *  Do not attempt to use it directly. @headername{filesystem}
      28   */
      29  
      30  #ifndef _GLIBCXX_FS_DIR_H
      31  #define _GLIBCXX_FS_DIR_H 1
      32  
      33  #if __cplusplus >= 201703L
      34  # include <typeinfo>
      35  # include <ext/concurrence.h>
      36  # include <bits/unique_ptr.h>
      37  # include <bits/shared_ptr.h>
      38  
      39  #if __cplusplus >= 202002L
      40  # include <compare>	// std::strong_ordering
      41  # include <bits/iterator_concepts.h>	// std::default_sentinel_t
      42  #endif
      43  
      44  namespace std _GLIBCXX_VISIBILITY(default)
      45  {
      46  _GLIBCXX_BEGIN_NAMESPACE_VERSION
      47  
      48  namespace filesystem
      49  {
      50    /** @addtogroup filesystem
      51     *  @{
      52     */
      53  
      54    /// Information about a file's type and permissions.
      55    /**
      56     * @headerfile filesystem
      57     * @since C++17
      58     */
      59    class file_status
      60    {
      61    public:
      62      // constructors and destructor
      63      file_status() noexcept : file_status(file_type::none) {}
      64  
      65      explicit
      66      file_status(file_type __ft, perms __prms = perms::unknown) noexcept
      67      : _M_type(__ft), _M_perms(__prms) { }
      68  
      69      file_status(const file_status&) noexcept = default;
      70      file_status(file_status&&) noexcept = default;
      71      ~file_status() = default;
      72  
      73      file_status& operator=(const file_status&) noexcept = default;
      74      file_status& operator=(file_status&&) noexcept = default;
      75  
      76      // observers
      77      file_type  type() const noexcept { return _M_type; }
      78      perms      permissions() const noexcept { return _M_perms; }
      79  
      80      // modifiers
      81      void       type(file_type __ft) noexcept { _M_type = __ft; }
      82      void       permissions(perms __prms) noexcept { _M_perms = __prms; }
      83  
      84  #if __cpp_lib_three_way_comparison
      85      friend bool
      86      operator==(const file_status&, const file_status&) noexcept = default;
      87  #endif
      88  
      89    private:
      90      file_type	_M_type;
      91      perms	_M_perms;
      92    };
      93  
      94  _GLIBCXX_BEGIN_NAMESPACE_CXX11
      95  
      96    struct _Dir;
      97    class directory_iterator;
      98    class recursive_directory_iterator;
      99  
     100    /// The value type used by directory iterators
     101    /**
     102     * @headerfile filesystem
     103     * @since C++17
     104     */
     105    class directory_entry
     106    {
     107    public:
     108      // constructors and destructor
     109      directory_entry() noexcept = default;
     110      directory_entry(const directory_entry&) = default;
     111      directory_entry(directory_entry&&) noexcept = default;
     112  
     113      explicit
     114      directory_entry(const filesystem::path& __p)
     115      : _M_path(__p)
     116      { refresh(); }
     117  
     118      directory_entry(const filesystem::path& __p, error_code& __ec)
     119      : _M_path(__p)
     120      {
     121        refresh(__ec);
     122        if (__ec)
     123  	_M_path.clear();
     124      }
     125  
     126      ~directory_entry() = default;
     127  
     128      // modifiers
     129      directory_entry& operator=(const directory_entry&) = default;
     130      directory_entry& operator=(directory_entry&&) noexcept = default;
     131  
     132      void
     133      assign(const filesystem::path& __p)
     134      {
     135        _M_path = __p;
     136        refresh();
     137      }
     138  
     139      void
     140      assign(const filesystem::path& __p, error_code& __ec)
     141      {
     142        _M_path = __p;
     143        refresh(__ec);
     144      }
     145  
     146      void
     147      replace_filename(const filesystem::path& __p)
     148      {
     149        _M_path.replace_filename(__p);
     150        refresh();
     151      }
     152  
     153      void
     154      replace_filename(const filesystem::path& __p, error_code& __ec)
     155      {
     156        _M_path.replace_filename(__p);
     157        refresh(__ec);
     158      }
     159  
     160      void
     161      refresh()
     162      { _M_type = symlink_status().type(); }
     163  
     164      void
     165      refresh(error_code& __ec) noexcept
     166      { _M_type = symlink_status(__ec).type(); }
     167  
     168      // observers
     169      const filesystem::path& path() const noexcept { return _M_path; }
     170      operator const filesystem::path& () const noexcept { return _M_path; }
     171  
     172      bool
     173      exists() const
     174      { return filesystem::exists(file_status{_M_file_type()}); }
     175  
     176      bool
     177      exists(error_code& __ec) const noexcept
     178      { return filesystem::exists(file_status{_M_file_type(__ec)}); }
     179  
     180      bool
     181      is_block_file() const
     182      { return _M_file_type() == file_type::block; }
     183  
     184      bool
     185      is_block_file(error_code& __ec) const noexcept
     186      { return _M_file_type(__ec) == file_type::block; }
     187  
     188      bool
     189      is_character_file() const
     190      { return _M_file_type() == file_type::character; }
     191  
     192      bool
     193      is_character_file(error_code& __ec) const noexcept
     194      { return _M_file_type(__ec) == file_type::character; }
     195  
     196      bool
     197      is_directory() const
     198      { return _M_file_type() == file_type::directory; }
     199  
     200      bool
     201      is_directory(error_code& __ec) const noexcept
     202      { return _M_file_type(__ec) == file_type::directory; }
     203  
     204      bool
     205      is_fifo() const
     206      { return _M_file_type() == file_type::fifo; }
     207  
     208      bool
     209      is_fifo(error_code& __ec) const noexcept
     210      { return _M_file_type(__ec) == file_type::fifo; }
     211  
     212      bool
     213      is_other() const
     214      { return filesystem::is_other(file_status{_M_file_type()}); }
     215  
     216      bool
     217      is_other(error_code& __ec) const noexcept
     218      { return filesystem::is_other(file_status{_M_file_type(__ec)}); }
     219  
     220      bool
     221      is_regular_file() const
     222      { return _M_file_type() == file_type::regular; }
     223  
     224      bool
     225      is_regular_file(error_code& __ec) const noexcept
     226      { return _M_file_type(__ec) == file_type::regular; }
     227  
     228      bool
     229      is_socket() const
     230      { return _M_file_type() == file_type::socket; }
     231  
     232      bool
     233      is_socket(error_code& __ec) const noexcept
     234      { return _M_file_type(__ec) == file_type::socket; }
     235  
     236      bool
     237      is_symlink() const
     238      {
     239        if (_M_type != file_type::none)
     240  	return _M_type == file_type::symlink;
     241        return symlink_status().type() == file_type::symlink;
     242      }
     243  
     244      bool
     245      is_symlink(error_code& __ec) const noexcept
     246      {
     247        if (_M_type != file_type::none)
     248  	return _M_type == file_type::symlink;
     249        return symlink_status(__ec).type() == file_type::symlink;
     250      }
     251  
     252      uintmax_t
     253      file_size() const
     254      { return filesystem::file_size(_M_path); }
     255  
     256      uintmax_t
     257      file_size(error_code& __ec) const noexcept
     258      { return filesystem::file_size(_M_path, __ec); }
     259  
     260      uintmax_t
     261      hard_link_count() const
     262      { return filesystem::hard_link_count(_M_path); }
     263  
     264      uintmax_t
     265      hard_link_count(error_code& __ec) const noexcept
     266      { return filesystem::hard_link_count(_M_path, __ec); }
     267  
     268      file_time_type
     269      last_write_time() const
     270      { return filesystem::last_write_time(_M_path); }
     271  
     272  
     273      file_time_type
     274      last_write_time(error_code& __ec) const noexcept
     275      { return filesystem::last_write_time(_M_path, __ec); }
     276  
     277      file_status
     278      status() const
     279      { return filesystem::status(_M_path); }
     280  
     281      file_status
     282      status(error_code& __ec) const noexcept
     283      { return filesystem::status(_M_path, __ec); }
     284  
     285      file_status
     286      symlink_status() const
     287      { return filesystem::symlink_status(_M_path); }
     288  
     289      file_status
     290      symlink_status(error_code& __ec) const noexcept
     291      { return filesystem::symlink_status(_M_path, __ec); }
     292  
     293      bool
     294      operator==(const directory_entry& __rhs) const noexcept
     295      { return _M_path == __rhs._M_path; }
     296  
     297  #if __cpp_lib_three_way_comparison
     298      strong_ordering
     299      operator<=>(const directory_entry& __rhs) const noexcept
     300      { return _M_path <=> __rhs._M_path; }
     301  #else
     302      bool
     303      operator!=(const directory_entry& __rhs) const noexcept
     304      { return _M_path != __rhs._M_path; }
     305  
     306      bool
     307      operator< (const directory_entry& __rhs) const noexcept
     308      { return _M_path < __rhs._M_path; }
     309  
     310      bool
     311      operator<=(const directory_entry& __rhs) const noexcept
     312      { return _M_path <= __rhs._M_path; }
     313  
     314      bool
     315      operator> (const directory_entry& __rhs) const noexcept
     316      { return _M_path > __rhs._M_path; }
     317  
     318      bool
     319      operator>=(const directory_entry& __rhs) const noexcept
     320      { return _M_path >= __rhs._M_path; }
     321  #endif
     322  
     323    private:
     324      friend struct _Dir;
     325      friend class directory_iterator;
     326      friend class recursive_directory_iterator;
     327  
     328      // _GLIBCXX_RESOLVE_LIB_DEFECTS
     329      // 3171. LWG 2989 breaks directory_entry stream insertion
     330      template<typename _CharT, typename _Traits>
     331        friend basic_ostream<_CharT, _Traits>&
     332        operator<<(basic_ostream<_CharT, _Traits>& __os,
     333  		 const directory_entry& __d)
     334        { return __os << __d.path(); }
     335  
     336      directory_entry(const filesystem::path& __p, file_type __t)
     337      : _M_path(__p), _M_type(__t)
     338      { }
     339  
     340      // Equivalent to status().type() but uses cached value, if any.
     341      file_type
     342      _M_file_type() const
     343      {
     344        if (_M_type != file_type::none && _M_type != file_type::symlink)
     345  	return _M_type;
     346        return status().type();
     347      }
     348  
     349      // Equivalent to status(__ec).type() but uses cached value, if any.
     350      file_type
     351      _M_file_type(error_code& __ec) const noexcept
     352      {
     353        if (_M_type != file_type::none && _M_type != file_type::symlink)
     354  	{
     355  	  __ec.clear();
     356  	  return _M_type;
     357  	}
     358        return status(__ec).type();
     359      }
     360  
     361      filesystem::path	_M_path;
     362      file_type		_M_type = file_type::none;
     363    };
     364  
     365    /// @cond undocumented
     366  
     367    /// Proxy returned by post-increment on directory iterators.
     368    /**
     369     * @headerfile filesystem
     370     * @since C++17
     371     */
     372    struct __directory_iterator_proxy
     373    {
     374      const directory_entry& operator*() const& noexcept { return _M_entry; }
     375  
     376      directory_entry operator*() && noexcept { return std::move(_M_entry); }
     377  
     378    private:
     379      friend class directory_iterator;
     380      friend class recursive_directory_iterator;
     381  
     382      explicit
     383      __directory_iterator_proxy(const directory_entry& __e) : _M_entry(__e) { }
     384  
     385      directory_entry _M_entry;
     386    };
     387    /// @endcond
     388  
     389    /// Iterator type for traversing the entries in a single directory.
     390    /**
     391     * @headerfile filesystem
     392     * @since C++17
     393     */
     394    class directory_iterator
     395    {
     396    public:
     397      typedef directory_entry        value_type;
     398      typedef ptrdiff_t              difference_type;
     399      typedef const directory_entry* pointer;
     400      typedef const directory_entry& reference;
     401      typedef input_iterator_tag     iterator_category;
     402  
     403      directory_iterator() = default;
     404  
     405      explicit
     406      directory_iterator(const path& __p)
     407      : directory_iterator(__p, directory_options::none, nullptr) { }
     408  
     409      directory_iterator(const path& __p, directory_options __options)
     410      : directory_iterator(__p, __options, nullptr) { }
     411  
     412      directory_iterator(const path& __p, error_code& __ec)
     413      : directory_iterator(__p, directory_options::none, __ec) { }
     414  
     415      directory_iterator(const path& __p, directory_options __options,
     416  		       error_code& __ec)
     417      : directory_iterator(__p, __options, &__ec) { }
     418  
     419      directory_iterator(const directory_iterator& __rhs) = default;
     420  
     421      directory_iterator(directory_iterator&& __rhs) noexcept = default;
     422  
     423      ~directory_iterator() = default;
     424  
     425      directory_iterator&
     426      operator=(const directory_iterator& __rhs) = default;
     427  
     428      directory_iterator&
     429      operator=(directory_iterator&& __rhs) noexcept = default;
     430  
     431      const directory_entry& operator*() const noexcept;
     432      const directory_entry* operator->() const noexcept { return &**this; }
     433      directory_iterator&    operator++();
     434      directory_iterator&    increment(error_code& __ec);
     435  
     436      __directory_iterator_proxy operator++(int)
     437      {
     438        __directory_iterator_proxy __pr{**this};
     439        ++*this;
     440        return __pr;
     441      }
     442  
     443      friend bool
     444      operator==(const directory_iterator& __lhs,
     445                 const directory_iterator& __rhs) noexcept
     446      {
     447        return !__rhs._M_dir.owner_before(__lhs._M_dir)
     448  	&& !__lhs._M_dir.owner_before(__rhs._M_dir);
     449      }
     450  
     451  #if __cplusplus >= 202002L
     452        // _GLIBCXX_RESOLVE_LIB_DEFECTS
     453        // 3719. Directory iterators should be usable with default sentinel
     454        bool operator==(default_sentinel_t) const noexcept
     455        { return !_M_dir; }
     456  #endif
     457  
     458  #if __cpp_impl_three_way_comparison < 201907L
     459      friend bool
     460      operator!=(const directory_iterator& __lhs,
     461  	       const directory_iterator& __rhs) noexcept
     462      { return !(__lhs == __rhs); }
     463  #endif
     464  
     465    private:
     466      directory_iterator(const path&, directory_options, error_code*);
     467  
     468      friend class recursive_directory_iterator;
     469  
     470      std::__shared_ptr<_Dir> _M_dir;
     471    };
     472  
     473    /** @relates std::filesystem::directory_iterator
     474     *  @headerfile filesystem
     475     *  @since C++17
     476     *  @{
     477     */
     478  
     479    /** @brief Enable range-based `for` using directory_iterator.
     480     *
     481     *  e.g. `for (auto& entry : std::filesystem::directory_iterator(".")) ...`
     482     */
     483    inline directory_iterator
     484    begin(directory_iterator __iter) noexcept
     485    { return __iter; }
     486  
     487    /// Return a past-the-end directory_iterator
     488    inline directory_iterator
     489    end(directory_iterator) noexcept
     490    { return directory_iterator(); }
     491    /// @}
     492  
     493    /// Iterator type for recursively traversing a directory hierarchy.
     494    /**
     495     *  @headerfile filesystem
     496     *  @since C++17
     497     */
     498    class recursive_directory_iterator
     499    {
     500    public:
     501      typedef directory_entry        value_type;
     502      typedef ptrdiff_t              difference_type;
     503      typedef const directory_entry* pointer;
     504      typedef const directory_entry& reference;
     505      typedef input_iterator_tag     iterator_category;
     506  
     507      recursive_directory_iterator() = default;
     508  
     509      explicit
     510      recursive_directory_iterator(const path& __p)
     511      : recursive_directory_iterator(__p, directory_options::none, nullptr) { }
     512  
     513      recursive_directory_iterator(const path& __p, directory_options __options)
     514      : recursive_directory_iterator(__p, __options, nullptr) { }
     515  
     516      recursive_directory_iterator(const path& __p, directory_options __options,
     517                                   error_code& __ec)
     518      : recursive_directory_iterator(__p, __options, &__ec) { }
     519  
     520      recursive_directory_iterator(const path& __p, error_code& __ec)
     521      : recursive_directory_iterator(__p, directory_options::none, &__ec) { }
     522  
     523      recursive_directory_iterator(
     524          const recursive_directory_iterator&) = default;
     525  
     526      recursive_directory_iterator(recursive_directory_iterator&&) = default;
     527  
     528      ~recursive_directory_iterator();
     529  
     530      // observers
     531      directory_options  options() const noexcept;
     532      int                depth() const noexcept;
     533      bool               recursion_pending() const noexcept;
     534  
     535      const directory_entry& operator*() const noexcept;
     536      const directory_entry* operator->() const noexcept { return &**this; }
     537  
     538      // modifiers
     539      recursive_directory_iterator&
     540      operator=(const recursive_directory_iterator& __rhs) noexcept;
     541      recursive_directory_iterator&
     542      operator=(recursive_directory_iterator&& __rhs) noexcept;
     543  
     544      recursive_directory_iterator& operator++();
     545      recursive_directory_iterator& increment(error_code& __ec);
     546  
     547      __directory_iterator_proxy operator++(int)
     548      {
     549        __directory_iterator_proxy __pr{**this};
     550        ++*this;
     551        return __pr;
     552      }
     553  
     554      void pop();
     555      void pop(error_code&);
     556  
     557      void disable_recursion_pending() noexcept;
     558  
     559      friend bool
     560      operator==(const recursive_directory_iterator& __lhs,
     561                 const recursive_directory_iterator& __rhs) noexcept
     562      {
     563        return !__rhs._M_dirs.owner_before(__lhs._M_dirs)
     564  	&& !__lhs._M_dirs.owner_before(__rhs._M_dirs);
     565      }
     566  
     567  #if __cplusplus >= 202002L
     568        // _GLIBCXX_RESOLVE_LIB_DEFECTS
     569        // 3719. Directory iterators should be usable with default sentinel
     570        bool operator==(default_sentinel_t) const noexcept
     571        { return !_M_dirs; }
     572  #endif
     573  
     574  #if __cpp_impl_three_way_comparison < 201907L
     575      friend bool
     576      operator!=(const recursive_directory_iterator& __lhs,
     577                 const recursive_directory_iterator& __rhs) noexcept
     578      { return !(__lhs == __rhs); }
     579  #endif
     580  
     581    private:
     582      recursive_directory_iterator(const path&, directory_options, error_code*);
     583  
     584      struct _Dir_stack;
     585      std::__shared_ptr<_Dir_stack> _M_dirs;
     586  
     587      recursive_directory_iterator&
     588      __erase(error_code* = nullptr);
     589  
     590      friend uintmax_t
     591      filesystem::remove_all(const path&, error_code&);
     592      friend uintmax_t
     593      filesystem::remove_all(const path&);
     594    };
     595  
     596    /** @relates std::filesystem::directory_iterator
     597     *  @headerfile filesystem
     598     *  @since C++17
     599     *  @{
     600     */
     601  
     602    /** @brief Enable range-based `for` using recursive_directory_iterator.
     603     *
     604     *  e.g. `for (auto& entry : recursive_directory_iterator(".")) ...`
     605     */
     606    inline recursive_directory_iterator
     607    begin(recursive_directory_iterator __iter) noexcept
     608    { return __iter; }
     609  
     610    /// Return a past-the-end recursive_directory_iterator
     611    inline recursive_directory_iterator
     612    end(recursive_directory_iterator) noexcept
     613    { return recursive_directory_iterator(); }
     614    /// @}
     615  
     616  _GLIBCXX_END_NAMESPACE_CXX11
     617  
     618    /// @} group filesystem
     619  } // namespace filesystem
     620  
     621    // Use explicit instantiations of these types. Any inconsistency in the
     622    // value of __default_lock_policy between code including this header and
     623    // the library will cause a linker error.
     624    extern template class
     625      __shared_ptr<filesystem::_Dir>;
     626    extern template class
     627      __shared_ptr<filesystem::recursive_directory_iterator::_Dir_stack>;
     628  
     629  _GLIBCXX_END_NAMESPACE_VERSION
     630  } // namespace std
     631  
     632  #endif // C++17
     633  
     634  #endif // _GLIBCXX_FS_DIR_H