libcxx/src/filesystem/directory_entry.cpp

   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 <__config>
  10 #include <cstdint>
  11 #include <filesystem>
  12 #include <system_error>
  13
  14 #include "file_descriptor.h"
  15 #include "posix_compat.h"
  16 #include "time_utils.h"
  17
  18 _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
  19
  20 error_code directory_entry::__do_refresh() noexcept {
  21   __data_.__reset();
  22   error_code failure_ec;
  23
  24   detail::StatT full_st;
  25   file_status st = detail::posix_lstat(__p_, full_st, &failure_ec);
  26   if (!status_known(st)) {
  27     __data_.__reset();
  28     return failure_ec;
  29   }
  30
  31   if (!_VSTD_FS::exists(st) || !_VSTD_FS::is_symlink(st)) {
  32     __data_.__cache_type_ = directory_entry::_RefreshNonSymlink;
  33     __data_.__type_ = st.type();
  34     __data_.__non_sym_perms_ = st.permissions();
  35   } else { // we have a symlink
  36     __data_.__sym_perms_ = st.permissions();
  37     // Get the information about the linked entity.
  38     // Ignore errors from stat, since we don't want errors regarding symlink
  39     // resolution to be reported to the user.
  40     error_code ignored_ec;
  41     st = detail::posix_stat(__p_, full_st, &ignored_ec);
  42
  43     __data_.__type_ = st.type();
  44     __data_.__non_sym_perms_ = st.permissions();
  45
  46     // If we failed to resolve the link, then only partially populate the
  47     // cache.
  48     if (!status_known(st)) {
  49       __data_.__cache_type_ = directory_entry::_RefreshSymlinkUnresolved;
  50       return error_code{};
  51     }
  52     // Otherwise, we resolved the link, potentially as not existing.
  53     // That's OK.
  54     __data_.__cache_type_ = directory_entry::_RefreshSymlink;
  55   }
  56
  57   if (_VSTD_FS::is_regular_file(st))
  58     __data_.__size_ = static_cast<uintmax_t>(full_st.st_size);
  59
  60   if (_VSTD_FS::exists(st)) {
  61     __data_.__nlink_ = static_cast<uintmax_t>(full_st.st_nlink);
  62
  63     // Attempt to extract the mtime, and fail if it's not representable using
  64     // file_time_type. For now we ignore the error, as we'll report it when
  65     // the value is actually used.
  66     error_code ignored_ec;
  67     __data_.__write_time_ =
  68         detail::__extract_last_write_time(__p_, full_st, &ignored_ec);
  69   }
  70
  71   return failure_ec;
  72 }
  73
  74 _LIBCPP_END_NAMESPACE_FILESYSTEM