login/tst-updwtmpx.c

   1 /* Basic test coverage for updwtmpx.
   2    Copyright (C) 2019-2023 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 License as
   7    published by the Free Software Foundation; either version 2.1 of the
   8    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; see the file COPYING.LIB.  If
  17    not, see <https://www.gnu.org/licenses/>.  */
  18
  19 /* This program runs a series of tests.  Each one calls updwtmpx
  20    twice, to write two records, optionally with misalignment in the
  21    file, and reads back the results.  */
  22
  23 #include <errno.h>
  24 #include <stdlib.h>
  25 #include <support/check.h>
  26 #include <support/descriptors.h>
  27 #include <support/support.h>
  28 #include <support/temp_file.h>
  29 #include <support/test-driver.h>
  30 #include <support/xunistd.h>
  31 #include <unistd.h>
  32 #include <utmpx.h>
  33
  34 static int
  35 do_test (void)
  36 {
  37   /* Two entries filled with an arbitrary bit pattern.  */
  38   struct utmpx entries[2];
  39   unsigned char pad;
  40   {
  41     unsigned char *p = (unsigned char *) &entries[0];
  42     for (size_t i = 0; i < sizeof (entries); ++i)
  43       {
  44         p[i] = i;
  45       }
  46     /* Make sure that the first and second entry and the padding are
  47        different.  */
  48     p[sizeof (struct utmpx)] = p[0] + 1;
  49     pad = p[0] + 2;
  50   }
  51
  52   char *path;
  53   int fd = create_temp_file ("tst-updwtmpx-", &path);
  54
  55   /* Used to check that updwtmpx does not leave an open file
  56      descriptor around.  */
  57   struct support_descriptors *descriptors = support_descriptors_list ();
  58
  59   /* updwtmpx is expected to remove misalignment.  Optionally insert
  60      one byte of misalignment at the start and in the middle (after
  61      the first entry).  */
  62   for (int misaligned_start = 0; misaligned_start < 2; ++misaligned_start)
  63     for (int misaligned_middle = 0; misaligned_middle < 2; ++misaligned_middle)
  64       {
  65         if (test_verbose > 0)
  66           printf ("info: misaligned_start=%d misaligned_middle=%d\n",
  67                   misaligned_start, misaligned_middle);
  68
  69         xftruncate (fd, 0);
  70         TEST_COMPARE (pwrite64 (fd, &pad, misaligned_start, 0),
  71                       misaligned_start);
  72
  73         /* Write first entry and check it.  */
  74         errno = 0;
  75         updwtmpx (path, &entries[0]);
  76         TEST_COMPARE (errno, 0);
  77         support_descriptors_check (descriptors);
  78         TEST_COMPARE (xlseek (fd, 0, SEEK_END), sizeof (struct utmpx));
  79         struct utmpx buffer;
  80         TEST_COMPARE (pread64 (fd, &buffer, sizeof (buffer), 0),
  81                       sizeof (buffer));
  82         TEST_COMPARE_BLOB (&entries[0], sizeof (entries[0]),
  83                            &buffer, sizeof (buffer));
  84
  85         /* Middle mis-alignmet.  */
  86         TEST_COMPARE (pwrite64 (fd, &pad, misaligned_middle,
  87                                 sizeof (struct utmpx)), misaligned_middle);
  88
  89         /* Write second entry and check both entries.  */
  90         errno = 0;
  91         updwtmpx (path, &entries[1]);
  92         TEST_COMPARE (errno, 0);
  93         support_descriptors_check (descriptors);
  94         TEST_COMPARE (xlseek (fd, 0, SEEK_END), 2 * sizeof (struct utmpx));
  95         TEST_COMPARE (pread64 (fd, &buffer, sizeof (buffer), 0),
  96                       sizeof (buffer));
  97         TEST_COMPARE_BLOB (&entries[0], sizeof (entries[0]),
  98                            &buffer, sizeof (buffer));
  99         TEST_COMPARE (pread64 (fd, &buffer, sizeof (buffer), sizeof (buffer)),
 100                       sizeof (buffer));
 101         TEST_COMPARE_BLOB (&entries[1], sizeof (entries[1]),
 102                            &buffer, sizeof (buffer));
 103       }
 104
 105   support_descriptors_free (descriptors);
 106   free (path);
 107   xclose (fd);
 108
 109   return 0;
 110 }
 111
 112 #include <support/test-driver.c>