tests/test-fwrite.c

   1 /* Test of fwrite() function.
   2    Copyright (C) 2011-2020 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 }