libstdc++-v3/testsuite/experimental/filesystem/operations/last_write_time.cc

   1 // Copyright (C) 2016-2021 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-options "-DUSE_FILESYSTEM_TS -lstdc++fs" }
  19 // { dg-do run { target c++11 } }
  20 // { dg-require-filesystem-ts "" }
  21
  22 // 15.25 Permissions [fs.op.last_write_time]
  23
  24 #include <experimental/filesystem>
  25 #include <limits>
  26 #include <testsuite_fs.h>
  27 #include <testsuite_hooks.h>
  28
  29 #ifdef _GLIBCXX_HAVE_FCNTL_H
  30 # include <fcntl.h>
  31 #endif
  32 #if _GLIBCXX_HAVE_UTIME_H
  33 # include <utime.h>
  34 #endif
  35 #include <stdio.h>
  36
  37 using time_type = std::experimental::filesystem::file_time_type;
  38
  39 namespace chrono = std::chrono;
  40
  41 void
  42 test01()
  43 {
  44   // read times
  45
  46   auto p = __gnu_test::nonexistent_path();
  47   std::error_code ec;
  48   time_type mtime = last_write_time(p, ec);
  49   VERIFY( ec );
  50   VERIFY( ec == std::make_error_code(std::errc::no_such_file_or_directory) );
  51 #if __cpp_exceptions
  52   bool caught = false;
  53   try {
  54     mtime = last_write_time(p);
  55   } catch (std::system_error const& e) {
  56     caught = true;
  57     ec = e.code();
  58   }
  59   VERIFY( caught );
  60   VERIFY( ec );
  61   VERIFY( ec == std::make_error_code(std::errc::no_such_file_or_directory) );
  62 #endif
  63
  64   __gnu_test::scoped_file file(p);
  65   VERIFY( exists(p) );
  66   mtime = last_write_time(p, ec);
  67   VERIFY( !ec );
  68   VERIFY( mtime <= time_type::clock::now() );
  69   VERIFY( mtime == last_write_time(p) );
  70
  71   auto end_of_time = time_type::duration::max();
  72   auto last_second
  73     = chrono::duration_cast<chrono::seconds>(end_of_time).count();
  74   if (last_second > std::numeric_limits<std::time_t>::max())
  75   {
  76     puts("Range of time_t is smaller than range of chrono::file_clock, "
  77          "can't test for overflow on this target.");
  78     return;
  79   }
  80
  81   // Set mtime to a date past the maximum possible file_time_type:
  82 #if _GLIBCXX_USE_UTIMENSAT
  83   struct ::timespec ts[2];
  84   ts[0].tv_sec = 0;
  85   ts[0].tv_nsec = UTIME_NOW;
  86   ts[1].tv_sec = std::numeric_limits<std::time_t>::max() - 1;
  87   ts[1].tv_nsec = 0;
  88   VERIFY( !::utimensat(AT_FDCWD, p.c_str(), ts, 0) );
  89 #elif _GLIBCXX_HAVE_UTIME_H
  90   ::utimbuf times;
  91   times.modtime = std::numeric_limits<std::time_t>::max() - 1;
  92   times.actime = std::numeric_limits<std::time_t>::max() - 1;
  93   VERIFY( !::utime(p.string().c_str(), &times) );
  94 #else
  95   puts("No utimensat or utime, giving up.");
  96   return;
  97 #endif
  98
  99   // Try to read back the impossibly-large mtime:
 100   mtime = last_write_time(p, ec);
 101   // Some filesystems (e.g. XFS) silently truncate distant times to
 102   // the time_t epochalypse, Jan 19 2038, so we won't get an error when
 103   // reading it back:
 104   if (ec)
 105   {
 106     VERIFY( ec == std::make_error_code(std::errc::value_too_large) );
 107     VERIFY( mtime == time_type::min() );
 108   }
 109   else
 110     puts("No overflow error, filesystem may not support 64-bit time_t.");
 111
 112 #if __cpp_exceptions
 113   // Once more, with exceptions:
 114   try {
 115     auto mtime2 = last_write_time(p);
 116     // If it didn't throw, expect to have read back the same value:
 117     VERIFY( mtime2 == mtime );
 118   } catch (std::experimental::filesystem::filesystem_error const& e) {
 119     // If it did throw, expect the error_code to be the same:
 120     VERIFY( e.code() == ec );
 121     VERIFY( e.path1() == p );
 122   }
 123 #endif
 124 }
 125
 126 bool approx_equal(time_type file_time, time_type expected)
 127 {
 128   auto delta = expected - file_time;
 129   if (delta < delta.zero())
 130     delta = -delta;
 131   return delta < chrono::seconds(1);
 132 }
 133
 134 void
 135 test02()
 136 {
 137   // write times
 138
 139   const std::error_code bad_ec = make_error_code(std::errc::invalid_argument);
 140   __gnu_test::scoped_file f;
 141   std::error_code ec;
 142   time_type time;
 143
 144   ec = bad_ec;
 145   time = last_write_time(f.path);
 146   last_write_time(f.path, time, ec);
 147   VERIFY( !ec );
 148   VERIFY( approx_equal(last_write_time(f.path), time) );
 149
 150   ec = bad_ec;
 151   time -= chrono::milliseconds(1000 * 60 * 10 + 15);
 152   last_write_time(f.path, time, ec);
 153   VERIFY( !ec );
 154   VERIFY( approx_equal(last_write_time(f.path), time) );
 155
 156   ec = bad_ec;
 157   time += chrono::milliseconds(1000 * 60 * 20 + 15);
 158   last_write_time(f.path, time, ec);
 159   VERIFY( !ec );
 160   VERIFY( approx_equal(last_write_time(f.path), time) );
 161
 162   ec = bad_ec;
 163   time = time_type();
 164   last_write_time(f.path, time, ec);
 165   VERIFY( !ec );
 166   VERIFY( approx_equal(last_write_time(f.path), time) );
 167
 168   ec = bad_ec;
 169   time -= chrono::milliseconds(1000 * 60 * 10 + 15);
 170   last_write_time(f.path, time, ec);
 171   VERIFY( !ec );
 172   VERIFY( approx_equal(last_write_time(f.path), time) );
 173 }
 174
 175 int
 176 main()
 177 {
 178   test01();
 179   test02();
 180 }