1/*
2 * Copyright (c) 2004, 2005, 2007 Darren Tucker (dtucker at zip com au).
3 *
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16
17#include "includes.h"
18#if !defined(HAVE_PPOLL) || !defined(HAVE_POLL) || defined(BROKEN_POLL)
19
20#include <sys/types.h>
21#include <sys/time.h>
22#ifdef HAVE_SYS_PARAM_H
23# include <sys/param.h>
24#endif
25#ifdef HAVE_SYS_SELECT_H
26# include <sys/select.h>
27#endif
28
29#include <errno.h>
30#include <signal.h>
31#include <stdlib.h>
32#include <unistd.h>
33#include "bsd-poll.h"
34
35#if !defined(HAVE_PPOLL) || defined(BROKEN_POLL)
36/*
37 * A minimal implementation of ppoll(2), built on top of pselect(2).
38 *
39 * Only supports POLLIN, POLLOUT and POLLPRI flags in pfd.events and
40 * revents. Notably POLLERR, POLLHUP and POLLNVAL are not supported.
41 *
42 * Supports pfd.fd = -1 meaning "unused" although it's not standard.
43 */
44
45int
46ppoll(struct pollfd *fds, nfds_t nfds, const struct timespec *tmoutp,
47    const sigset_t *sigmask)
48{
49	nfds_t i;
50	int ret, fd, maxfd = 0;
51	fd_set readfds, writefds, exceptfds;
52
53	for (i = 0; i < nfds; i++) {
54		fd = fds[i].fd;
55		if (fd != -1 && fd >= FD_SETSIZE) {
56			errno = EINVAL;
57			return -1;
58		}
59		maxfd = MAX(maxfd, fd);
60	}
61
62	/* populate event bit vectors for the events we're interested in */
63	FD_ZERO(&readfds);
64	FD_ZERO(&writefds);
65	FD_ZERO(&exceptfds);
66	for (i = 0; i < nfds; i++) {
67		fd = fds[i].fd;
68		if (fd == -1)
69			continue;
70		if (fds[i].events & POLLIN)
71			FD_SET(fd, &readfds);
72		if (fds[i].events & POLLOUT)
73			FD_SET(fd, &writefds);
74		if (fds[i].events & POLLPRI)
75			FD_SET(fd, &exceptfds);
76	}
77
78	ret = pselect(maxfd + 1, &readfds, &writefds, &exceptfds, tmoutp, sigmask);
79
80	/* scan through select results and set poll() flags */
81	for (i = 0; i < nfds; i++) {
82		fd = fds[i].fd;
83		fds[i].revents = 0;
84		if (fd == -1)
85			continue;
86		if ((fds[i].events & POLLIN) && FD_ISSET(fd, &readfds))
87			fds[i].revents |= POLLIN;
88		if ((fds[i].events & POLLOUT) && FD_ISSET(fd, &writefds))
89			fds[i].revents |= POLLOUT;
90		if ((fds[i].events & POLLPRI) && FD_ISSET(fd, &exceptfds))
91			fds[i].revents |= POLLPRI;
92	}
93
94	return ret;
95}
96#endif /* !HAVE_PPOLL || BROKEN_POLL */
97
98#if !defined(HAVE_POLL) || defined(BROKEN_POLL)
99int
100poll(struct pollfd *fds, nfds_t nfds, int timeout)
101{
102	struct timespec ts, *tsp = NULL;
103
104	/* poll timeout is msec, ppoll is timespec (sec + nsec) */
105	if (timeout >= 0) {
106		ts.tv_sec = timeout / 1000;
107		ts.tv_nsec = (timeout % 1000) * 1000000;
108		tsp = &ts;
109	}
110
111	return ppoll(fds, nfds, tsp, NULL);
112}
113#endif /* !HAVE_POLL || BROKEN_POLL */
114
115#endif /* !HAVE_PPOLL || !HAVE_POLL || BROKEN_POLL */
116