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Comparing libev/ev_poll.c (file contents):
Revision 1.2 by root, Fri Nov 2 16:54:35 2007 UTC vs.
Revision 1.42 by root, Mon Jun 24 21:27:57 2019 UTC

1/* 1/*
2 * libev epoll fd activity backend 2 * libev poll fd activity backend
3 * 3 *
4 * Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de> 4 * Copyright (c) 2007,2008,2009,2010,2011,2016,2019 Marc Alexander Lehmann <libev@schmorp.de>
5 * All rights reserved. 5 * All rights reserved.
6 * 6 *
7 * Redistribution and use in source and binary forms, with or without 7 * Redistribution and use in source and binary forms, with or without modifica-
8 * modification, are permitted provided that the following conditions are 8 * tion, are permitted provided that the following conditions are met:
9 * met:
10 * 9 *
11 * * Redistributions of source code must retain the above copyright 10 * 1. Redistributions of source code must retain the above copyright notice,
12 * notice, this list of conditions and the following disclaimer. 11 * this list of conditions and the following disclaimer.
13 * 12 *
14 * * Redistributions in binary form must reproduce the above 13 * 2. Redistributions in binary form must reproduce the above copyright
15 * copyright notice, this list of conditions and the following 14 * notice, this list of conditions and the following disclaimer in the
16 * disclaimer in the documentation and/or other materials provided 15 * documentation and/or other materials provided with the distribution.
17 * with the distribution.
18 * 16 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
23 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 21 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
25 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 25 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 * OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Alternatively, the contents of this file may be used under the terms of
29 * the GNU General Public License ("GPL") version 2 or any later version,
30 * in which case the provisions of the GPL are applicable instead of
31 * the above. If you wish to allow the use of your version of this file
32 * only under the terms of the GPL and not to allow others to use your
33 * version of this file under the BSD license, indicate your decision
34 * by deleting the provisions above and replace them with the notice
35 * and other provisions required by the GPL. If you do not delete the
36 * provisions above, a recipient may use your version of this file under
37 * either the BSD or the GPL.
30 */ 38 */
31 39
32#include <poll.h> 40#include <poll.h>
33 41
34static struct pollfd *polls; 42inline_size
35static int pollmax, pollcnt; 43void
36static int *pollidxs; /* maps fds into structure indices */ 44array_needsize_pollidx (int *base, int offset, int count)
37static int pollidxmax;
38
39static void
40pollidx_init (int *base, int count)
41{ 45{
46 /* using memset (.., -1, ...) is tempting, we we try
47 * to be ultraportable
48 */
49 base += offset;
42 while (count--) 50 while (count--)
43 *base++ = -1; 51 *base++ = -1;
44} 52}
45 53
46static void 54static void
47poll_modify (int fd, int oev, int nev) 55poll_modify (EV_P_ int fd, int oev, int nev)
48{ 56{
49 int idx; 57 int idx;
58
59 if (oev == nev)
60 return;
61
50 array_needsize (pollidxs, pollidxmax, fd + 1, pollidx_init); 62 array_needsize (int, pollidxs, pollidxmax, fd + 1, array_needsize_pollidx);
51 63
52 idx = pollidxs [fd]; 64 idx = pollidxs [fd];
53 65
54 if (idx < 0) /* need to allocate a new pollfd */ 66 if (idx < 0) /* need to allocate a new pollfd */
55 { 67 {
56 idx = pollcnt++; 68 pollidxs [fd] = idx = pollcnt++;
57 array_needsize (polls, pollmax, pollcnt, ); 69 array_needsize (struct pollfd, polls, pollmax, pollcnt, array_needsize_noinit);
58 polls [idx].fd = fd; 70 polls [idx].fd = fd;
59 } 71 }
72
73 assert (polls [idx].fd == fd);
60 74
61 if (nev) 75 if (nev)
62 polls [idx].events = 76 polls [idx].events =
63 (nev & EV_READ ? POLLIN : 0) 77 (nev & EV_READ ? POLLIN : 0)
64 | (nev & EV_WRITE ? POLLOUT : 0); 78 | (nev & EV_WRITE ? POLLOUT : 0);
65 else /* remove pollfd */ 79 else /* remove pollfd */
66 { 80 {
67 if (idx < pollcnt--) 81 pollidxs [fd] = -1;
82
83 if (expect_true (idx < --pollcnt))
68 { 84 {
69 pollidxs [fd] = -1;
70 polls [idx] = polls [pollcnt]; 85 polls [idx] = polls [pollcnt];
71 pollidxs [polls [idx].fd] = idx; 86 pollidxs [polls [idx].fd] = idx;
72 } 87 }
73 } 88 }
74} 89}
75 90
76static void 91static void
77poll_poll (ev_tstamp timeout) 92poll_poll (EV_P_ ev_tstamp timeout)
78{ 93{
94 struct pollfd *p;
95 int res;
96
97 EV_RELEASE_CB;
79 int res = poll (polls, pollcnt, ceil (timeout * 1000.)); 98 res = poll (polls, pollcnt, timeout * 1e3);
99 EV_ACQUIRE_CB;
80 100
81 if (res > 0) 101 if (expect_false (res < 0))
82 {
83 int i;
84
85 for (i = 0; i < pollcnt; ++i)
86 fd_event (
87 polls [i].fd,
88 (polls [i].revents & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0)
89 | (polls [i].revents & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0)
90 );
91 }
92 else if (res < 0)
93 { 102 {
94 if (errno == EBADF) 103 if (errno == EBADF)
95 fd_ebadf (); 104 fd_ebadf (EV_A);
96 else if (errno == ENOMEM) 105 else if (errno == ENOMEM && !syserr_cb)
97 fd_enomem (); 106 fd_enomem (EV_A);
107 else if (errno != EINTR)
108 ev_syserr ("(libev) poll");
98 } 109 }
110 else
111 for (p = polls; res; ++p)
112 {
113 assert (("libev: poll() returned illegal result, broken BSD kernel?", p < polls + pollcnt));
114
115 if (expect_false (p->revents)) /* this expect is debatable */
116 {
117 --res;
118
119 if (expect_false (p->revents & POLLNVAL))
120 fd_kill (EV_A_ p->fd);
121 else
122 fd_event (
123 EV_A_
124 p->fd,
125 (p->revents & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0)
126 | (p->revents & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0)
127 );
128 }
129 }
99} 130}
100 131
101static void 132inline_size
133int
102poll_init (int flags) 134poll_init (EV_P_ int flags)
103{ 135{
104 ev_method = EVMETHOD_POLL; 136 backend_mintime = 1e-3;
105 method_fudge = 1e-3; /* needed to compensate for select returning early, very conservative */
106 method_modify = poll_modify; 137 backend_modify = poll_modify;
107 method_poll = poll_poll; 138 backend_poll = poll_poll;
139
140 pollidxs = 0; pollidxmax = 0;
141 polls = 0; pollmax = 0; pollcnt = 0;
142
143 return EVBACKEND_POLL;
108} 144}
145
146inline_size
147void
148poll_destroy (EV_P)
149{
150 ev_free (pollidxs);
151 ev_free (polls);
152}
153

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