glibc/sysdeps/unix/sysv/linux/fcntl.c

103 lines
2.4 KiB
C

/* Copyright (C) 2000-2014 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <assert.h>
#include <errno.h>
#include <sysdep-cancel.h> /* Must come before <fcntl.h>. */
#include <fcntl.h>
#include <stdarg.h>
#include <sys/syscall.h>
#include <kernel-features.h>
#ifdef __ASSUME_F_GETOWN_EX
# define miss_F_GETOWN_EX 0
#else
static int miss_F_GETOWN_EX;
#endif
static int
do_fcntl (int fd, int cmd, void *arg)
{
if (cmd != F_GETOWN || miss_F_GETOWN_EX)
return INLINE_SYSCALL (fcntl, 3, fd, cmd, arg);
INTERNAL_SYSCALL_DECL (err);
struct f_owner_ex fex;
int res = INTERNAL_SYSCALL (fcntl, err, 3, fd, F_GETOWN_EX, &fex);
if (!INTERNAL_SYSCALL_ERROR_P (res, err))
return fex.type == F_OWNER_GID ? -fex.pid : fex.pid;
#ifndef __ASSUME_F_GETOWN_EX
if (INTERNAL_SYSCALL_ERRNO (res, err) == EINVAL)
{
res = INLINE_SYSCALL (fcntl, 3, fd, F_GETOWN, arg);
miss_F_GETOWN_EX = 1;
return res;
}
#endif
__set_errno (INTERNAL_SYSCALL_ERRNO (res, err));
return -1;
}
#ifndef NO_CANCELLATION
int
__fcntl_nocancel (int fd, int cmd, ...)
{
va_list ap;
void *arg;
va_start (ap, cmd);
arg = va_arg (ap, void *);
va_end (ap);
return do_fcntl (fd, cmd, arg);
}
#endif
int
__libc_fcntl (int fd, int cmd, ...)
{
va_list ap;
void *arg;
va_start (ap, cmd);
arg = va_arg (ap, void *);
va_end (ap);
if (SINGLE_THREAD_P || cmd != F_SETLKW)
return do_fcntl (fd, cmd, arg);
int oldtype = LIBC_CANCEL_ASYNC ();
int result = do_fcntl (fd, cmd, arg);
LIBC_CANCEL_RESET (oldtype);
return result;
}
libc_hidden_def (__libc_fcntl)
weak_alias (__libc_fcntl, __fcntl)
libc_hidden_weak (__fcntl)
weak_alias (__libc_fcntl, fcntl)