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
45 int
ppoll(struct pollfd * fds,nfds_t nfds,const struct timespec * tmoutp,const sigset_t * sigmask)46 ppoll(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)
99 int
poll(struct pollfd * fds,nfds_t nfds,int timeout)100 poll(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