1 /*
2 * This file and its contents are supplied under the terms of the
3 * Common Development and Distribution License ("CDDL"), version 1.0.
4 * You may only use this file in accordance with the terms of version
5 * 1.0 of the CDDL.
6 *
7 * A full copy of the text of the CDDL should have accompanied this
8 * source. A copy of the CDDL is also available via the Internet at
9 * http://www.illumos.org/license/CDDL.
10 */
11
12 /*
13 * Copyright 2015, Joyent, Inc.
14 */
15
16 #include <sys/signalfd.h>
17 #include <sys/stat.h>
18 #include <unistd.h>
19 #include <errno.h>
20 #include <fcntl.h>
21
22 int
signalfd(int fd,const sigset_t * mask,int flags)23 signalfd(int fd, const sigset_t *mask, int flags)
24 {
25 int origfd = fd;
26
27 if (fd == -1) {
28 int oflags = O_RDONLY;
29
30 if (flags & ~(SFD_NONBLOCK | SFD_CLOEXEC)) {
31 errno = EINVAL;
32 return (-1);
33 }
34
35 if (flags & SFD_NONBLOCK)
36 oflags |= O_NONBLOCK;
37
38 if (flags & SFD_CLOEXEC)
39 oflags |= O_CLOEXEC;
40
41 if ((fd = open("/dev/signalfd", oflags)) < 0)
42 return (-1);
43 }
44
45 if (ioctl(fd, SIGNALFDIOC_MASK, mask) != 0) {
46 if (origfd == -1) {
47 int old = errno;
48 (void) close(fd);
49 errno = old;
50 }
51 /*
52 * Trying to modify an existing sigfd so if this failed
53 * it's because it's not a valid fd or not a sigfd. ioctl
54 * returns the correct errno for these cases.
55 */
56 return (-1);
57 }
58
59 return (fd);
60 }
61