posix/tst-truncate-common.c

   1 /* Common f{truncate} tests definitions.
   2    Copyright (C) 2016-2024 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 <unistd.h>
  20 #include <sys/types.h>
  21 #include <sys/stat.h>
  22 #include <unistd.h>
  23
  24 #include <support/check.h>
  25
  26 static void do_prepare (void);
  27 #define PREPARE(argc, argv)     do_prepare ()
  28 static int do_test (void);
  29 #define TEST_FUNCTION           do_test ()
  30
  31 #include <test-skeleton.c>
  32
  33 static char *temp_filename;
  34 static int temp_fd;
  35
  36 static void
  37 do_prepare (void)
  38 {
  39   temp_fd = create_temp_file ("tst-trucate.", &temp_filename);
  40   if (temp_fd == -1)
  41     {
  42       printf ("cannot create temporary file: %m\n");
  43       exit (1);
  44     }
  45 }
  46
  47 static int
  48 do_test_with_offset (off_t offset)
  49 {
  50   struct stat st;
  51   char buf[1000];
  52
  53   memset (buf, 0xcf, sizeof (buf));
  54
  55   if (pwrite (temp_fd, buf, sizeof (buf), offset) != sizeof (buf))
  56     FAIL_RET ("write failed");
  57   if (fstat (temp_fd, &st) < 0 || st.st_size != (offset + sizeof (buf)))
  58     FAIL_RET ("initial size wrong");
  59
  60   if (ftruncate (temp_fd, offset + 800) < 0)
  61     FAIL_RET ("size reduction with ftruncate failed");
  62   if (fstat (temp_fd, &st) < 0 || st.st_size != (offset + 800))
  63     FAIL_RET ("size after reduction with ftruncate is incorrect");
  64
  65   /* The following test covers more than POSIX.  POSIX does not require
  66      that ftruncate() can increase the file size.  But we are testing
  67      Unix systems.  */
  68   if (ftruncate (temp_fd, offset + 1200) < 0)
  69     FAIL_RET ("size increate with ftruncate failed");
  70   if (fstat (temp_fd, &st) < 0 || st.st_size != (offset + 1200))
  71     FAIL_RET ("size after increase is incorrect");
  72
  73   if (truncate (temp_filename, offset + 800) < 0)
  74     FAIL_RET ("size reduction with truncate failed");
  75   if (fstat (temp_fd, &st) < 0 || st.st_size != (offset + 800))
  76     FAIL_RET ("size after reduction with truncate incorrect");
  77
  78   /* The following test covers more than POSIX.  POSIX does not require
  79      that truncate() can increase the file size.  But we are testing
  80      Unix systems.  */
  81   if (truncate (temp_filename, (offset + 1200)) < 0)
  82     FAIL_RET ("size increase with truncate failed");
  83   if (fstat (temp_fd, &st) < 0 || st.st_size != (offset + 1200))
  84     FAIL_RET ("size increase with truncate is incorrect");
  85
  86   return 0;
  87 }