stdio-common/tst-fmemopen4.c

   1 /* fmemopen tests for BZ#1930 and BZ#20005.
   2    Copyright (C) 2016-2023 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
   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 <assert.h>
  20 #include <stdio.h>
  21 #include <string.h>
  22 #include <sys/types.h>
  23
  24
  25 /* Check if fflush does not reset the file position.  */
  26 static int
  27 do_test (void)
  28 {
  29   char buffer[500] = "x";
  30
  31   FILE *stream = fmemopen (buffer, sizeof (buffer), "r+");
  32   if (stream == NULL)
  33     {
  34       printf ("error: fmemopen could not open stream\n");
  35       return 1;
  36     }
  37
  38   const char test[] = "test";
  39
  40   size_t r = fwrite (test, sizeof (char), sizeof (test), stream);
  41   if (r != sizeof (test))
  42     {
  43       printf ("error: fwrite returned %zu, expected %zu\n", r, sizeof (test));
  44       return 1;
  45     }
  46
  47   r = ftell (stream);
  48   if (r != sizeof (test))
  49     {
  50       printf ("error: ftell return %zu, expected %zu\n", r, sizeof (test));
  51       return 1;
  52     }
  53
  54   if (fflush (stream) != 0)
  55     {
  56       printf ("error: fflush failed\n");
  57       return 1;
  58     }
  59
  60   r = ftell (stream);
  61   if (r != sizeof (test))
  62     {
  63       printf ("error: ftell return %zu, expected %zu\n", r, sizeof (test));
  64       return 1;
  65     }
  66
  67   return 0;
  68 }
  69
  70 #define TEST_FUNCTION do_test ()
  71 #include "../test-skeleton.c"