tests/test-fchdir.c

   1 /* Test changing to a directory named by a file descriptor.
   2    Copyright (C) 2009-2024 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program 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
  15    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Eric Blake <ebb9@byu.net>, 2009.  */
  18
  19 #include <config.h>
  20
  21 #include <unistd.h>
  22
  23 #include "signature.h"
  24 SIGNATURE_CHECK (fchdir, int, (int));
  25
  26 #include <errno.h>
  27 #include <fcntl.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30
  31 #include "cloexec.h"
  32 #include "macros.h"
  33
  34 int
  35 main (void)
  36 {
  37   char *cwd;
  38   int fd;
  39   int i;
  40
  41   cwd = getcwd (NULL, 0);
  42   ASSERT (cwd);
  43
  44   fd = open (".", O_RDONLY);
  45   ASSERT (0 <= fd);
  46
  47   /* Test behaviour for invalid file descriptors.  */
  48   {
  49     errno = 0;
  50     ASSERT (fchdir (-1) == -1);
  51     ASSERT (errno == EBADF);
  52   }
  53   {
  54     close (99);
  55     errno = 0;
  56     ASSERT (fchdir (99) == -1);
  57     ASSERT (errno == EBADF);
  58   }
  59
  60   /* Check for other failure cases.  */
  61   {
  62     int bad_fd = open ("/dev/null", O_RDONLY);
  63     ASSERT (0 <= bad_fd);
  64     errno = 0;
  65     ASSERT (fchdir (bad_fd) == -1);
  66     ASSERT (errno == ENOTDIR);
  67     ASSERT (close (bad_fd) == 0);
  68   }
  69
  70   /* Repeat test twice, once in '.' and once in '..'.  */
  71   for (i = 0; i < 2; i++)
  72     {
  73       ASSERT (chdir (&".."[1 - i]) == 0);
  74       ASSERT (fchdir (fd) == 0);
  75       {
  76         size_t len = strlen (cwd) + 1;
  77         char *new_dir = malloc (len);
  78         ASSERT (new_dir);
  79         ASSERT (getcwd (new_dir, len) == new_dir);
  80         ASSERT (strcmp (cwd, new_dir) == 0);
  81         free (new_dir);
  82       }
  83
  84       /* For second iteration, use a cloned fd, to ensure that dup
  85          remembers whether an fd was associated with a directory.  */
  86       if (!i)
  87         {
  88           int new_fd = dup (fd);
  89           ASSERT (0 <= new_fd);
  90           ASSERT (close (fd) == 0);
  91           ASSERT (dup2 (new_fd, fd) == fd);
  92           ASSERT (close (new_fd) == 0);
  93           ASSERT (dup_cloexec (fd) == new_fd);
  94           ASSERT (dup2 (new_fd, fd) == fd);
  95           ASSERT (close (new_fd) == 0);
  96           ASSERT (fcntl (fd, F_DUPFD_CLOEXEC, new_fd) == new_fd);
  97           ASSERT (close (fd) == 0);
  98           ASSERT (fcntl (new_fd, F_DUPFD, fd) == fd);
  99           ASSERT (close (new_fd) == 0);
 100 #if GNULIB_TEST_DUP3
 101           ASSERT (dup3 (fd, new_fd, 0) == new_fd);
 102           ASSERT (dup3 (new_fd, fd, 0) == fd);
 103           ASSERT (close (new_fd) == 0);
 104 #endif
 105         }
 106     }
 107
 108   free (cwd);
 109   return test_exit_status;
 110 }