xref: /freebsd/lib/libc/gen/eventfd.c (revision f126890ac5386406dadf7c4cfa9566cbb56537c5)
1 /*-
2  * SPDX-License-Identifier: MIT
3  *
4  * Copyright (c) 2005-2020 Rich Felker, et al.
5  * Copyright (c) 2020 Val Packett
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining
8  * a copy of this software and associated documentation files (the
9  * "Software"), to deal in the Software without restriction, including
10  * without limitation the rights to use, copy, modify, merge, publish,
11  * distribute, sublicense, and/or sell copies of the Software, and to
12  * permit persons to whom the Software is furnished to do so, subject to
13  * the following conditions:
14  *
15  * The above copyright notice and this permission notice shall be
16  * included in all copies or substantial portions of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
21  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
22  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25  */
26 
27 #include "namespace.h"
28 #include <sys/eventfd.h>
29 #include <sys/specialfd.h>
30 #include <unistd.h>
31 #include "un-namespace.h"
32 #include "libc_private.h"
33 
34 int eventfd(unsigned int initval, int flags)
35 {
36 	struct specialfd_eventfd args;
37 
38 	args.initval = initval;
39 	args.flags = flags;
40 	return (__sys___specialfd(SPECIALFD_EVENTFD, &args, sizeof(args)));
41 }
42 
43 int eventfd_read(int fd, eventfd_t *value)
44 {
45 	return (sizeof(*value) == _read(fd, value, sizeof(*value)) ? 0 : -1);
46 }
47 
48 int eventfd_write(int fd, eventfd_t value)
49 {
50 	return (sizeof(value) == _write(fd, &value, sizeof(value)) ? 0 : -1);
51 }
52