source: trunk/src/sed/gnulib-tests/test-pipe.c

/* Test of pipe.
   Copyright (C) 2009-2022 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, see <https://www.gnu.org/licenses/>.  */

#include <config.h>

#include <unistd.h>

#include "signature.h"
SIGNATURE_CHECK (pipe, int, (int[2]));

#include <fcntl.h>

#if defined _WIN32 && ! defined __CYGWIN__
/* Get declarations of the native Windows API functions.  */
# define WIN32_LEAN_AND_MEAN
# include <windows.h>
/* Get _get_osfhandle.  */
# if GNULIB_MSVC_NOTHROW
#  include "msvc-nothrow.h"
# else
#  include <io.h>
# endif
#endif

#include "binary-io.h"
#include "macros.h"

/* Return true if FD is open.  */
static bool
is_open (int fd)
{
#if defined _WIN32 && ! defined __CYGWIN__
  /* On native Windows, the initial state of unassigned standard file
     descriptors is that they are open but point to an
     INVALID_HANDLE_VALUE, and there is no fcntl.  */
  return (HANDLE) _get_osfhandle (fd) != INVALID_HANDLE_VALUE;
#else
# ifndef F_GETFL
#  error Please port fcntl to your platform
# endif
  return 0 <= fcntl (fd, F_GETFL);
#endif
}

/* Return true if FD is not inherited to child processes.  */
static bool
is_cloexec (int fd)
{
#if defined _WIN32 && ! defined __CYGWIN__
  HANDLE h = (HANDLE) _get_osfhandle (fd);
  DWORD flags;
  ASSERT (GetHandleInformation (h, &flags));
  return (flags & HANDLE_FLAG_INHERIT) == 0;
#else
  int flags;
  ASSERT ((flags = fcntl (fd, F_GETFD)) >= 0);
  return (flags & FD_CLOEXEC) != 0;
#endif
}

/* Return true if FD is in non-blocking mode.  */
static bool
is_nonblocking (int fd)
{
#if defined _WIN32 && ! defined __CYGWIN__
  /* We don't use the non-blocking mode for sockets here.  */
  return 0;
#else
  int flags;
  ASSERT ((flags = fcntl (fd, F_GETFL)) >= 0);
  return (flags & O_NONBLOCK) != 0;
#endif
}

int
main ()
{
  int fd[2];

  fd[0] = -1;
  fd[1] = -1;
  ASSERT (pipe (fd) >= 0);
  ASSERT (fd[0] >= 0);
  ASSERT (fd[1] >= 0);
  ASSERT (fd[0] != fd[1]);
  ASSERT (is_open (fd[0]));
  ASSERT (is_open (fd[1]));
  ASSERT (!is_cloexec (fd[0]));
  ASSERT (!is_cloexec (fd[1]));
  ASSERT (!is_nonblocking (fd[0]));
  ASSERT (!is_nonblocking (fd[1]));

  return 0;
}