1/* Copyright (C) 2007-2016 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Lesser General Public
6 License as published by the Free Software Foundation; either
7 version 2.1 of the License, or (at your option) any later version.
8
9 The GNU C Library 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 GNU
12 Lesser General Public License for more details.
13
14 You should have received a copy of the GNU Lesser General Public
15 License along with the GNU C Library; if not, see
16 <http://www.gnu.org/licenses/>. */
17
18#include <errno.h>
19#include <sys/eventfd.h>
20#include <sysdep.h>
21#include <kernel-features.h>
22
23
24int
25eventfd (unsigned int count, int flags)
26{
27#ifdef __NR_eventfd2
28 int res = INLINE_SYSCALL (eventfd2, 2, count, flags);
29# ifndef __ASSUME_EVENTFD2
30 if (res != -1 || errno != ENOSYS)
31# endif
32 return res;
33#endif
34
35#ifndef __ASSUME_EVENTFD2
36 /* The old system call has no flag parameter which is bad. So we have
37 to wait until we have to support to pass additional values to the
38 kernel (sys_indirect) before implementing setting flags like
39 O_NONBLOCK etc. */
40 if (flags != 0)
41 return INLINE_SYSCALL_ERROR_RETURN_VALUE (EINVAL);
42
43# ifdef __NR_eventfd
44 return INLINE_SYSCALL (eventfd, 1, count);
45# else
46 return INLINE_SYSCALL_ERROR_RETURN_VALUE (ENOSYS);
47# endif
48#elif !defined __NR_eventfd2
49# error "__ASSUME_EVENTFD2 defined but not __NR_eventfd2"
50#endif
51}
52