/* Test of fcntl(2).

   Copyright (C) 2009-2020 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 of the License, 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/>.  */

/* Written by Eric Blake <ebb9@byu.net>, 2009.  */

#include <config.h>

/* Specification.  */

#include <fcntl.h>

#include "signature.h"

SIGNATURE_CHECK (fcntl, int, (int, int, ...));

/* Helpers.  */

#include <errno.h>

#include <stdarg.h>

#include <stdbool.h>

#include <unistd.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"

#if !O_BINARY

# define setmode(f,m) zero ()

static int zero (void) { return 0; }

#endif

/* 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 open and inheritable across exec/spawn.  */

static bool

is_inheritable (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.  */

  HANDLE h = (HANDLE) _get_osfhandle (fd);

  DWORD flags;

  if (h == INVALID_HANDLE_VALUE || GetHandleInformation (h, &flags) == 0)

    return false;

  return (flags & HANDLE_FLAG_INHERIT) != 0;

#else

# ifndef F_GETFD

#  error Please port fcntl to your platform

# endif

  int i = fcntl (fd, F_GETFD);

  return 0 <= i && (i & FD_CLOEXEC) == 0;

#endif

}

/* Return non-zero if FD is open in the given MODE, which is either

   O_TEXT or O_BINARY.  */

static bool

is_mode (int fd, int mode)

{

  int value = setmode (fd, O_BINARY);

  setmode (fd, value);

  return mode == value;

}

/* Since native fcntl can have more supported operations than our

   replacement is aware of, and since various operations assign

   different types to the vararg argument, a wrapper around fcntl must

   be able to pass a vararg of unknown type on through to the original

   fcntl.  Make sure that this works properly: func1 behaves like the

   original fcntl interpreting the vararg as an int or a pointer to a

   struct, and func2 behaves like rpl_fcntl that doesn't know what

   type to forward.  */

struct dummy_struct

{

  long filler;

  int value;

};

static int

func1 (int a, ...)

{

  va_list arg;

  int i;

  va_start (arg, a);

  if (a < 4)

    i = va_arg (arg, int);

  else

    {

      struct dummy_struct *s = va_arg (arg, struct dummy_struct *);

      i = s->value;

    }

  va_end (arg);

  return i;

}

static int

func2 (int a, ...)

{

  va_list arg;

  void *p;

  va_start (arg, a);

  p = va_arg (arg, void *);

  va_end (arg);

  return func1 (a, p);

}

/* Ensure that all supported fcntl actions are distinct, and

   usable in preprocessor expressions.  */

static void

check_flags (void)

{

  switch (0)

    {

    case F_DUPFD:

#if F_DUPFD

#endif

    case F_DUPFD_CLOEXEC:

#if F_DUPFD_CLOEXEC

#endif

    case F_GETFD:

#if F_GETFD

#endif

#ifdef F_SETFD

    case F_SETFD:

# if F_SETFD

# endif

#endif

#ifdef F_GETFL

    case F_GETFL:

# if F_GETFL

# endif

#endif

#ifdef F_SETFL

    case F_SETFL:

# if F_SETFL

# endif

#endif

#ifdef F_GETOWN

    case F_GETOWN:

# if F_GETOWN

# endif

#endif

#ifdef F_SETOWN

    case F_SETOWN:

# if F_SETOWN

# endif

#endif

#ifdef F_GETLK

    case F_GETLK:

# if F_GETLK

# endif

#endif

#ifdef F_SETLK

    case F_SETLK:

# if F_SETLK

# endif

#endif

#ifdef F_SETLKW

    case F_SETLKW:

# if F_SETLKW

# endif

#endif

      ;

    }

}

int

main (void)

{

  const char *file = "test-fcntl.tmp";

  int fd;

  int bad_fd = getdtablesize ();

  /* Sanity check that rpl_fcntl is likely to work.  */

  ASSERT (func2 (1, 2) == 2);

  ASSERT (func2 (2, -2) == -2);

  ASSERT (func2 (3, 0x80000000) == 0x80000000);

  {

    struct dummy_struct s = { 0L, 4 };

    ASSERT (func2 (4, &s) == 4);

  }

  check_flags ();

  /* Assume std descriptors were provided by invoker, and ignore fds

     that might have been inherited.  */

  fd = creat (file, 0600);

  ASSERT (STDERR_FILENO < fd);

  close (fd + 1);

  close (fd + 2);

  /* For F_DUPFD*, the source must be valid.  */

  errno = 0;

  ASSERT (fcntl (-1, F_DUPFD, 0) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (fd + 1, F_DUPFD, 0) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (bad_fd, F_DUPFD, 0) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (-1, F_DUPFD_CLOEXEC, 0) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (fd + 1, F_DUPFD_CLOEXEC, 0) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (bad_fd, F_DUPFD_CLOEXEC, 0) == -1);

  ASSERT (errno == EBADF);

  /* For F_DUPFD*, the destination must be valid.  */

  errno = 0;

  ASSERT (fcntl (fd, F_DUPFD, -1) == -1);

  ASSERT (errno == EINVAL);

  errno = 0;

  ASSERT (fcntl (fd, F_DUPFD, bad_fd) == -1);

  ASSERT (errno == EINVAL);

  errno = 0;

  ASSERT (fcntl (fd, F_DUPFD_CLOEXEC, -1) == -1);

  ASSERT (errno == EINVAL);

  errno = 0;

  ASSERT (fcntl (fd, F_DUPFD_CLOEXEC, bad_fd) == -1);

  ASSERT (errno == EINVAL

          || errno == EMFILE /* WSL */);

  /* For F_DUPFD*, check for correct inheritance, as well as

     preservation of text vs. binary.  */

  setmode (fd, O_BINARY);

  ASSERT (is_open (fd));

  ASSERT (!is_open (fd + 1));

  ASSERT (!is_open (fd + 2));

  ASSERT (is_inheritable (fd));

  ASSERT (is_mode (fd, O_BINARY));

  ASSERT (fcntl (fd, F_DUPFD, fd) == fd + 1);

  ASSERT (is_open (fd));

  ASSERT (is_open (fd + 1));

  ASSERT (!is_open (fd + 2));

  ASSERT (is_inheritable (fd + 1));

  ASSERT (is_mode (fd, O_BINARY));

  ASSERT (is_mode (fd + 1, O_BINARY));

  ASSERT (close (fd + 1) == 0);

  ASSERT (fcntl (fd, F_DUPFD_CLOEXEC, fd + 2) == fd + 2);

  ASSERT (is_open (fd));

  ASSERT (!is_open (fd + 1));

  ASSERT (is_open (fd + 2));

  ASSERT (is_inheritable (fd));

  ASSERT (!is_inheritable (fd + 2));

  ASSERT (is_mode (fd, O_BINARY));

  ASSERT (is_mode (fd + 2, O_BINARY));

  ASSERT (close (fd) == 0);

  setmode (fd + 2, O_TEXT);

  ASSERT (fcntl (fd + 2, F_DUPFD, fd + 1) == fd + 1);

  ASSERT (!is_open (fd));

  ASSERT (is_open (fd + 1));

  ASSERT (is_open (fd + 2));

  ASSERT (is_inheritable (fd + 1));

  ASSERT (!is_inheritable (fd + 2));

  ASSERT (is_mode (fd + 1, O_TEXT));

  ASSERT (is_mode (fd + 2, O_TEXT));

  ASSERT (close (fd + 1) == 0);

  ASSERT (fcntl (fd + 2, F_DUPFD_CLOEXEC, 0) == fd);

  ASSERT (is_open (fd));

  ASSERT (!is_open (fd + 1));

  ASSERT (is_open (fd + 2));

  ASSERT (!is_inheritable (fd));

  ASSERT (!is_inheritable (fd + 2));

  ASSERT (is_mode (fd, O_TEXT));

  ASSERT (is_mode (fd + 2, O_TEXT));

  ASSERT (close (fd + 2) == 0);

  /* Test F_GETFD on invalid file descriptors.  */

  errno = 0;

  ASSERT (fcntl (-1, F_GETFD) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (fd + 1, F_GETFD) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (bad_fd, F_GETFD) == -1);

  ASSERT (errno == EBADF);

  /* Test F_GETFD, the FD_CLOEXEC bit.  */

  {

    int result = fcntl (fd, F_GETFD);

    ASSERT (0 <= result);

    ASSERT ((result & FD_CLOEXEC) == FD_CLOEXEC);

    ASSERT (dup (fd) == fd + 1);

    result = fcntl (fd + 1, F_GETFD);

    ASSERT (0 <= result);

    ASSERT ((result & FD_CLOEXEC) == 0);

    ASSERT (close (fd + 1) == 0);

  }

#ifdef F_SETFD

  /* Test F_SETFD on invalid file descriptors.  */

  errno = 0;

  ASSERT (fcntl (-1, F_SETFD, 0) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (fd + 1, F_SETFD, 0) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (bad_fd, F_SETFD, 0) == -1);

  ASSERT (errno == EBADF);

#endif

#ifdef F_GETFL

  /* Test F_GETFL on invalid file descriptors.  */

  errno = 0;

  ASSERT (fcntl (-1, F_GETFL) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (fd + 1, F_GETFL) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (bad_fd, F_GETFL) == -1);

  ASSERT (errno == EBADF);

#endif

#ifdef F_SETFL

  /* Test F_SETFL on invalid file descriptors.  */

  errno = 0;

  ASSERT (fcntl (-1, F_SETFL, 0) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (fd + 1, F_SETFL, 0) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (bad_fd, F_SETFL, 0) == -1);

  ASSERT (errno == EBADF);

#endif

#ifdef F_GETOWN

  /* Test F_GETOWN on invalid file descriptors.  */

  errno = 0;

  ASSERT (fcntl (-1, F_GETOWN) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (fd + 1, F_GETOWN) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (bad_fd, F_GETOWN) == -1);

  ASSERT (errno == EBADF);

#endif

#ifdef F_SETOWN

  /* Test F_SETFL on invalid file descriptors.  */

  errno = 0;

  ASSERT (fcntl (-1, F_SETOWN, 0) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (fd + 1, F_SETOWN, 0) == -1);

  ASSERT (errno == EBADF);

  errno = 0;

  ASSERT (fcntl (bad_fd, F_SETOWN, 0) == -1);

  ASSERT (errno == EBADF);

#endif

  /* Cleanup.  */

  ASSERT (close (fd) == 0);

  ASSERT (unlink (file) == 0);

  return 0;

}