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 saved_errno, ret, fd, maxfd = 0;
51 fd_set *readfds = NULL, *writefds = NULL, *exceptfds = NULL;
52 size_t nmemb;
53
54 for (i = 0; i < nfds; i++) {
55 fd = fds[i].fd;
56 if (fd != -1 && fd >= FD_SETSIZE) {
57 errno = EINVAL;
58 return -1;
59 }
60 maxfd = MAX(maxfd, fd);
61 }
62
63 nmemb = howmany(maxfd + 1 , NFDBITS);
64 if ((readfds = calloc(nmemb, sizeof(fd_mask))) == NULL ||
65 (writefds = calloc(nmemb, sizeof(fd_mask))) == NULL ||
66 (exceptfds = calloc(nmemb, sizeof(fd_mask))) == NULL) {
67 saved_errno = ENOMEM;
68 ret = -1;
69 goto out;
70 }
71
72 /* populate event bit vectors for the events we're interested in */
73 for (i = 0; i < nfds; i++) {
74 fd = fds[i].fd;
75 if (fd == -1)
76 continue;
77 if (fds[i].events & POLLIN)
78 FD_SET(fd, readfds);
79 if (fds[i].events & POLLOUT)
80 FD_SET(fd, writefds);
81 if (fds[i].events & POLLPRI)
82 FD_SET(fd, exceptfds);
83 }
84
85 ret = pselect(maxfd + 1, readfds, writefds, exceptfds, tmoutp, sigmask);
86 saved_errno = errno;
87
88 /* scan through select results and set poll() flags */
89 for (i = 0; i < nfds; i++) {
90 fd = fds[i].fd;
91 fds[i].revents = 0;
92 if (fd == -1)
93 continue;
94 if ((fds[i].events & POLLIN) && FD_ISSET(fd, readfds))
95 fds[i].revents |= POLLIN;
96 if ((fds[i].events & POLLOUT) && FD_ISSET(fd, writefds))
97 fds[i].revents |= POLLOUT;
98 if ((fds[i].events & POLLPRI) && FD_ISSET(fd, exceptfds))
99 fds[i].revents |= POLLPRI;
100 }
101
102 out:
103 free(readfds);
104 free(writefds);
105 free(exceptfds);
106 if (ret == -1)
107 errno = saved_errno;
108 return ret;
109 }
110 #endif /* !HAVE_PPOLL || BROKEN_POLL */
111
112 #if !defined(HAVE_POLL) || defined(BROKEN_POLL)
113 int
poll(struct pollfd * fds,nfds_t nfds,int timeout)114 poll(struct pollfd *fds, nfds_t nfds, int timeout)
115 {
116 struct timespec ts, *tsp = NULL;
117
118 /* poll timeout is msec, ppoll is timespec (sec + nsec) */
119 if (timeout >= 0) {
120 ts.tv_sec = timeout / 1000;
121 ts.tv_nsec = (timeout % 1000) * 1000000;
122 tsp = &ts;
123 }
124
125 return ppoll(fds, nfds, tsp, NULL);
126 }
127 #endif /* !HAVE_POLL || BROKEN_POLL */
128
129 #endif /* !HAVE_PPOLL || !HAVE_POLL || BROKEN_POLL */
130