stdio-common/tst-renameat2.c

   1 /* Linux implementation for renameat2 function.
   2    Copyright (C) 2018-2024 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library.  If not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <array_length.h>
  20 #include <errno.h>
  21 #include <fcntl.h>
  22 #include <stdbool.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <support/check.h>
  26 #include <support/support.h>
  27 #include <support/temp_file.h>
  28 #include <support/xunistd.h>
  29 #include <unistd.h>
  30
  31 /* Directory with the temporary files.  */
  32 static char *directory;
  33 static int directory_fd;
  34
  35 /* Paths within that directory.  */
  36 static char *old_path;          /* File is called "old".  */
  37 static char *new_path;          /* File is called "new".  */
  38
  39 /* Subdirectory within the directory above.  */
  40 static char *subdirectory;
  41 int subdirectory_fd;
  42
  43 /* And a pathname in that directory (called "file").  */
  44 static char *subdir_path;
  45
  46 static void
  47 prepare (int argc, char **argv)
  48 {
  49   directory = support_create_temp_directory ("tst-renameat2-");
  50   directory_fd = xopen (directory, O_RDONLY | O_DIRECTORY, 0);
  51   old_path = xasprintf ("%s/old", directory);
  52   add_temp_file (old_path);
  53   new_path = xasprintf ("%s/new", directory);
  54   add_temp_file (new_path);
  55   subdirectory = xasprintf ("%s/subdir", directory);
  56   xmkdir (subdirectory, 0777);
  57   add_temp_file (subdirectory);
  58   subdirectory_fd = xopen (subdirectory, O_RDONLY | O_DIRECTORY, 0);
  59   subdir_path = xasprintf ("%s/file", subdirectory);
  60   add_temp_file (subdir_path);
  61 }
  62
  63 /* Delete all files, preparing a clean slate for the next test.  */
  64 static void
  65 delete_all_files (void)
  66 {
  67   char *files[] = { old_path, new_path, subdir_path };
  68   for (size_t i = 0; i < array_length (files); ++i)
  69     if (unlink (files[i]) != 0 && errno != ENOENT)
  70       FAIL_EXIT1 ("unlink (\"%s\"): %m", files[i]);
  71 }
  72
  73 /* Return true if PATH exists in the file system.  */
  74 static bool
  75 file_exists (const char *path)
  76 {
  77   return access (path, F_OK) == 0;
  78 }
  79
  80 /* Check that PATH exists and has size EXPECTED_SIZE.  */
  81 static void
  82 check_size (const char *path, off64_t expected_size)
  83 {
  84   struct stat64 st;
  85   xstat (path, &st);
  86   if (st.st_size != expected_size)
  87     FAIL_EXIT1 ("file \"%s\": expected size %lld, actual size %lld",
  88                 path, (unsigned long long int) expected_size,
  89                 (unsigned long long int) st.st_size);
  90 }
  91
  92 /* Rename tests where the target does not exist.  */
  93 static void
  94 rename_without_existing_target (unsigned int flags)
  95 {
  96   delete_all_files ();
  97   support_write_file_string (old_path, "");
  98   TEST_COMPARE (renameat2 (AT_FDCWD, old_path, AT_FDCWD, new_path, flags), 0);
  99   TEST_VERIFY (!file_exists (old_path));
 100   TEST_VERIFY (file_exists (new_path));
 101
 102   delete_all_files ();
 103   support_write_file_string (old_path, "");
 104   TEST_COMPARE (renameat2 (directory_fd, "old", AT_FDCWD, new_path, flags), 0);
 105   TEST_VERIFY (!file_exists (old_path));
 106   TEST_VERIFY (file_exists (new_path));
 107
 108   delete_all_files ();
 109   support_write_file_string (old_path, "");
 110   TEST_COMPARE (renameat2 (directory_fd, "old", subdirectory_fd, "file", 0),
 111                 0);
 112   TEST_VERIFY (!file_exists (old_path));
 113   TEST_VERIFY (file_exists (subdir_path));
 114 }
 115
 116 static int
 117 do_test (void)
 118 {
 119   /* Tests with zero flags argument.  These are expected to succeed
 120      because this renameat2 variant can be implemented with
 121      renameat.  */
 122   rename_without_existing_target (0);
 123
 124   /* renameat2 without flags replaces an existing destination.  */
 125   delete_all_files ();
 126   support_write_file_string (old_path, "123");
 127   support_write_file_string (new_path, "1234");
 128   TEST_COMPARE (renameat2 (AT_FDCWD, old_path, AT_FDCWD, new_path, 0), 0);
 129   TEST_VERIFY (!file_exists (old_path));
 130   check_size (new_path, 3);
 131
 132   /* Now we need to check for kernel support of renameat2 with
 133      flags.  */
 134   delete_all_files ();
 135   support_write_file_string (old_path, "");
 136   if (renameat2 (AT_FDCWD, old_path, AT_FDCWD, new_path, RENAME_NOREPLACE)
 137       != 0)
 138     {
 139       if (errno == EINVAL)
 140         puts ("warning: no support for renameat2 with flags");
 141       else
 142         FAIL_EXIT1 ("renameat2 probe failed: %m");
 143     }
 144   else
 145     {
 146       /* We have full renameat2 support.  */
 147       rename_without_existing_target (RENAME_NOREPLACE);
 148
 149       /* Now test RENAME_NOREPLACE with an existing target.  */
 150       delete_all_files ();
 151       support_write_file_string (old_path, "123");
 152       support_write_file_string (new_path, "1234");
 153       TEST_COMPARE (renameat2 (AT_FDCWD, old_path, AT_FDCWD, new_path,
 154                                RENAME_NOREPLACE), -1);
 155       TEST_COMPARE (errno, EEXIST);
 156       check_size (old_path, 3);
 157       check_size (new_path, 4);
 158
 159       delete_all_files ();
 160       support_write_file_string (old_path, "123");
 161       support_write_file_string (new_path, "1234");
 162       TEST_COMPARE (renameat2 (directory_fd, "old", AT_FDCWD, new_path,
 163                                RENAME_NOREPLACE), -1);
 164       TEST_COMPARE (errno, EEXIST);
 165       check_size (old_path, 3);
 166       check_size (new_path, 4);
 167
 168       delete_all_files ();
 169       support_write_file_string (old_path, "123");
 170       support_write_file_string (subdir_path, "1234");
 171       TEST_COMPARE (renameat2 (directory_fd, "old", subdirectory_fd, "file",
 172                                RENAME_NOREPLACE), -1);
 173       TEST_COMPARE (errno, EEXIST);
 174       check_size (old_path, 3);
 175       check_size (subdir_path, 4);
 176
 177       /* The flag combination of RENAME_NOREPLACE and RENAME_EXCHANGE
 178          is invalid.  */
 179       TEST_COMPARE (renameat2 (directory_fd, "ignored",
 180                                subdirectory_fd, "ignored",
 181                                RENAME_NOREPLACE | RENAME_EXCHANGE), -1);
 182       TEST_COMPARE (errno, EINVAL);
 183     }
 184
 185   /* Create all the pathnames to avoid warnings from the test
 186      harness.  */
 187   support_write_file_string (old_path, "");
 188   support_write_file_string (new_path, "");
 189   support_write_file_string (subdir_path, "");
 190
 191   free (directory);
 192   free (subdirectory);
 193   free (old_path);
 194   free (new_path);
 195   free (subdir_path);
 196
 197   xclose (directory_fd);
 198   xclose (subdirectory_fd);
 199
 200   return 0;
 201 }
 202
 203 #define PREPARE prepare
 204 #include <support/test-driver.c>