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"