tests/test-fread.c

   1 /* Test of fread() 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 (fread, size_t, (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-fread.txt";
  38
  39   /* We don't have an fread() 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   /* Prepare a file.  */
  47   {
  48     const char text[] = "hello world";
  49     int fd = open (filename, O_RDWR | O_CREAT | O_TRUNC, 0600);
  50     ASSERT (fd >= 0);
  51     ASSERT (write (fd, text, sizeof (text)) == sizeof (text));
  52     ASSERT (close (fd) == 0);
  53   }
  54
  55   /* Test that fread() sets errno if someone else closes the stream
  56      fd behind the back of stdio.  */
  57   {
  58     FILE *fp = fopen (filename, "r");
  59     char buf[5];
  60     ASSERT (fp != NULL);
  61     ASSERT (close (fileno (fp)) == 0);
  62     errno = 0;
  63     ASSERT (fread (buf, 1, sizeof (buf), fp) == 0);
  64     ASSERT (errno == EBADF);
  65     ASSERT (ferror (fp));
  66     fclose (fp);
  67   }
  68
  69   /* Test that fread() sets errno if the stream was constructed with
  70      an invalid file descriptor.  */
  71   {
  72     FILE *fp = fdopen (-1, "r");
  73     if (fp != NULL)
  74       {
  75         char buf[1];
  76         errno = 0;
  77         ASSERT (fread (buf, 1, 1, fp) == 0);
  78         ASSERT (errno == EBADF);
  79         ASSERT (ferror (fp));
  80         fclose (fp);
  81       }
  82   }
  83   {
  84     FILE *fp;
  85     close (99);
  86     fp = fdopen (99, "r");
  87     if (fp != NULL)
  88       {
  89         char buf[1];
  90         errno = 0;
  91         ASSERT (fread (buf, 1, 1, fp) == 0);
  92         ASSERT (errno == EBADF);
  93         ASSERT (ferror (fp));
  94         fclose (fp);
  95       }
  96   }
  97
  98   /* Clean up.  */
  99   unlink (filename);
 100
 101   return 0;
 102 }