tests/test-fwrite.c

   1 /* Test of fwrite() function.
   2    Copyright (C) 2011-2024 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 ()
  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   #if !defined __ANDROID__ /* fdsan */
  49   {
  50     FILE *fp = fopen (filename, "w");
  51     char buf[5] = "world";
  52     ASSERT (fp != NULL);
  53     setvbuf (fp, NULL, _IONBF, 0);
  54     ASSERT (close (fileno (fp)) == 0);
  55     errno = 0;
  56     ASSERT (fwrite (buf, 1, sizeof (buf), fp) == 0);
  57     ASSERT (errno == EBADF);
  58     ASSERT (ferror (fp));
  59     fclose (fp);
  60   }
  61   #endif
  62
  63   /* Test that fwrite() on an unbuffered stream sets errno if the stream
  64      was constructed with an invalid file descriptor.  */
  65   {
  66     FILE *fp = fdopen (-1, "w");
  67     if (fp != NULL)
  68       {
  69         char buf[5] = "world";
  70         setvbuf (fp, NULL, _IONBF, 0);
  71         errno = 0;
  72         ASSERT (fwrite (buf, 1, sizeof (buf), fp) == 0);
  73         ASSERT (errno == EBADF);
  74         ASSERT (ferror (fp));
  75         fclose (fp);
  76       }
  77   }
  78   {
  79     FILE *fp;
  80     close (99);
  81     fp = fdopen (99, "w");
  82     if (fp != NULL)
  83       {
  84         char buf[5] = "world";
  85         setvbuf (fp, NULL, _IONBF, 0);
  86         errno = 0;
  87         ASSERT (fwrite (buf, 1, sizeof (buf), fp) == 0);
  88         ASSERT (errno == EBADF);
  89         ASSERT (ferror (fp));
  90         fclose (fp);
  91       }
  92   }
  93
  94   /* Clean up.  */
  95   unlink (filename);
  96
  97   return test_exit_status;
  98 }