tests/test-fread.c

   1 /* Test of fread() 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 (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 ()
  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   #if !defined __ANDROID__ /* fdsan */
  58   {
  59     FILE *fp = fopen (filename, "r");
  60     char buf[5];
  61     ASSERT (fp != NULL);
  62     ASSERT (close (fileno (fp)) == 0);
  63     errno = 0;
  64     ASSERT (fread (buf, 1, sizeof (buf), fp) == 0);
  65     ASSERT (errno == EBADF);
  66     ASSERT (ferror (fp));
  67     fclose (fp);
  68   }
  69   #endif
  70
  71   /* Test that fread() sets errno if the stream was constructed with
  72      an invalid file descriptor.  */
  73   {
  74     FILE *fp = fdopen (-1, "r");
  75     if (fp != NULL)
  76       {
  77         char buf[1];
  78         errno = 0;
  79         ASSERT (fread (buf, 1, 1, fp) == 0);
  80         ASSERT (errno == EBADF);
  81         ASSERT (ferror (fp));
  82         fclose (fp);
  83       }
  84   }
  85   {
  86     FILE *fp;
  87     close (99);
  88     fp = fdopen (99, "r");
  89     if (fp != NULL)
  90       {
  91         char buf[1];
  92         errno = 0;
  93         ASSERT (fread (buf, 1, 1, fp) == 0);
  94         ASSERT (errno == EBADF);
  95         ASSERT (ferror (fp));
  96         fclose (fp);
  97       }
  98   }
  99
 100   /* Clean up.  */
 101   unlink (filename);
 102
 103   return test_exit_status;
 104 }