1  /* Test of fwrite() function.
       2     Copyright (C) 2011-2022 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, or (at your option)
       7     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  #include <config.h>
      18  
      19  #include <stdio.h>
      20  
      21  #include "signature.h"
      22  SIGNATURE_CHECK (fwrite, size_t, (const void *, size_t, size_t, FILE *));
      23  
      24  #include <errno.h>
      25  #include <fcntl.h>
      26  #include <unistd.h>
      27  
      28  #if HAVE_MSVC_INVALID_PARAMETER_HANDLER
      29  # include "msvc-inval.h"
      30  #endif
      31  
      32  #include "macros.h"
      33  
      34  int
      35  main (int argc, char **argv)
      36  {
      37    const char *filename = "test-fwrite.txt";
      38  
      39    /* We don't have an fwrite() function that installs an invalid parameter
      40       handler so far.  So install that handler here, explicitly.  */
      41  #if HAVE_MSVC_INVALID_PARAMETER_HANDLER \
      42      && MSVC_INVALID_PARAMETER_HANDLING == DEFAULT_HANDLING
      43    gl_msvc_inval_ensure_handler ();
      44  #endif
      45  
      46    /* Test that fwrite() on an unbuffered stream sets errno if someone else
      47       closes the stream fd behind the back of stdio.  */
      48    {
      49      FILE *fp = fopen (filename, "w");
      50      char buf[5] = "world";
      51      ASSERT (fp != NULL);
      52      setvbuf (fp, NULL, _IONBF, 0);
      53      ASSERT (close (fileno (fp)) == 0);
      54      errno = 0;
      55      ASSERT (fwrite (buf, 1, sizeof (buf), fp) == 0);
      56      ASSERT (errno == EBADF);
      57      ASSERT (ferror (fp));
      58      fclose (fp);
      59    }
      60  
      61    /* Test that fwrite() on an unbuffered stream sets errno if the stream
      62       was constructed with an invalid file descriptor.  */
      63    {
      64      FILE *fp = fdopen (-1, "w");
      65      if (fp != NULL)
      66        {
      67          char buf[5] = "world";
      68          setvbuf (fp, NULL, _IONBF, 0);
      69          errno = 0;
      70          ASSERT (fwrite (buf, 1, sizeof (buf), fp) == 0);
      71          ASSERT (errno == EBADF);
      72          ASSERT (ferror (fp));
      73          fclose (fp);
      74        }
      75    }
      76    {
      77      FILE *fp;
      78      close (99);
      79      fp = fdopen (99, "w");
      80      if (fp != NULL)
      81        {
      82          char buf[5] = "world";
      83          setvbuf (fp, NULL, _IONBF, 0);
      84          errno = 0;
      85          ASSERT (fwrite (buf, 1, sizeof (buf), fp) == 0);
      86          ASSERT (errno == EBADF);
      87          ASSERT (ferror (fp));
      88          fclose (fp);
      89        }
      90    }
      91  
      92    /* Clean up.  */
      93    unlink (filename);
      94  
      95    return 0;
      96  }