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Comparing libev/ev_kqueue.c (file contents):
Revision 1.2 by root, Fri Nov 2 21:17:30 2007 UTC vs.
Revision 1.33 by root, Tue Dec 25 07:05:45 2007 UTC

1
2/* 1/*
2 * libev kqueue backend
3 *
3 * Copyright 2007 Marc Alexander Lehmann <libev@schmorp.de> 4 * Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de>
4 * Copyright 2000-2002 Niels Provos <provos@citi.umich.edu>
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 8 * tion, are permitted provided that the following conditions are met:
9 * are met: 9 *
10 * 1. Redistributions of source code must retain the above copyright notice,
11 * this list of conditions and the following disclaimer.
12 *
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
18 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
19 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
20 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
21 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
22 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
23 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
24 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
25 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
26 * OF THE POSSIBILITY OF SUCH DAMAGE.
10 * 27 *
11 * 1. Redistributions of source code must retain the above copyright 28 * Alternatively, the contents of this file may be used under the terms of
12 * notice, this list of conditions and the following disclaimer. 29 * the GNU General Public License ("GPL") version 2 or any later version,
13 * 2. Redistributions in binary form must reproduce the above copyright 30 * in which case the provisions of the GPL are applicable instead of
14 * notice, this list of conditions and the following disclaimer in the 31 * the above. If you wish to allow the use of your version of this file
15 * documentation and/or other materials provided with the distribution. 32 * only under the terms of the GPL and not to allow others to use your
16 * 3. The name of the author may not be used to endorse or promote products 33 * version of this file under the BSD license, indicate your decision
17 * derived from this software without specific prior written permission. 34 * by deleting the provisions above and replace them with the notice
18 * 35 * and other provisions required by the GPL. If you do not delete the
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 36 * provisions above, a recipient may use your version of this file under
20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 37 * either the BSD or the GPL.
21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */ 38 */
30 39
31#include <sys/types.h> 40#include <sys/types.h>
32#include <sys/time.h> 41#include <sys/time.h>
33#include <sys/queue.h> 42#include <sys/queue.h>
34#include <sys/event.h> 43#include <sys/event.h>
35#include <string.h> 44#include <string.h>
36#include <errno.h> 45#include <errno.h>
37 46
38static int kq_fd; 47void inline_speed
39static struct kevent *kq_changes; 48kqueue_change (EV_P_ int fd, int filter, int flags, int fflags)
40static int kq_changemax, kq_changecnt; 49{
41static struct kevent *kq_events; 50 ++kqueue_changecnt;
42static int kq_eventmax; 51 array_needsize (struct kevent, kqueue_changes, kqueue_changemax, kqueue_changecnt, EMPTY2);
52
53 EV_SET (&kqueue_changes [kqueue_changecnt - 1], fd, filter, flags, fflags, 0, 0);
54}
55
56#ifndef NOTE_EOF
57# define NOTE_EOF 0
58#endif
43 59
44static void 60static void
45kqueue_change (int fd, int filter, int flags, int fflags) 61kqueue_modify (EV_P_ int fd, int oev, int nev)
46{ 62{
47 struct kevent *ke; 63 if (oev != nev)
64 {
65 if (oev & EV_READ)
66 kqueue_change (EV_A_ fd, EVFILT_READ , EV_DELETE, 0);
48 67
49 array_needsize (kq_changes, kq_changemax, ++kq_changecnt, ); 68 if (oev & EV_WRITE)
69 kqueue_change (EV_A_ fd, EVFILT_WRITE, EV_DELETE, 0);
70 }
50 71
51 ke = &kq_changes [kq_changecnt - 1]; 72 /* to detect close/reopen reliably, we have to re-add */
52 memset (ke, 0, sizeof (struct kevent)); 73 /* event requests even when oev == nev */
53 ke->ident = fd; 74
54 ke->filter = filter; 75 if (nev & EV_READ)
55 ke->flags = flags; 76 kqueue_change (EV_A_ fd, EVFILT_READ , EV_ADD, NOTE_EOF);
56 ke->fflags = fflags; 77
78 if (nev & EV_WRITE)
79 kqueue_change (EV_A_ fd, EVFILT_WRITE, EV_ADD, NOTE_EOF);
57} 80}
58 81
59static void 82static void
60kqueue_modify (int fd, int oev, int nev)
61{
62 if ((oev ^ new) & EV_READ)
63 {
64 if (nev & EV_READ)
65 kqueue_change (fd, EVFILT_READ, EV_ADD, NOTE_EOF);
66 else
67 kqueue_change (fd, EVFILT_READ, EV_DELETE, 0);
68 }
69
70 if ((oev ^ new) & EV_WRITE)
71 {
72 if (nev & EV_WRITE)
73 kqueue_change (fd, EVFILT_WRITE, EV_ADD, NOTE_EOF);
74 else
75 kqueue_change (fd, EVFILT_WRITE, EV_DELETE, 0);
76 }
77}
78
79static void
80kqueue_poll (ev_tstamp timeout) 83kqueue_poll (EV_P_ ev_tstamp timeout)
81{ 84{
82 int res, i; 85 int res, i;
83 struct timespec ts; 86 struct timespec ts;
84 87
88 /* need to resize so there is enough space for errors */
89 if (kqueue_changecnt > kqueue_eventmax)
90 {
91 ev_free (kqueue_events);
92 kqueue_eventmax = array_nextsize (sizeof (struct kevent), kqueue_eventmax, kqueue_changecnt);
93 kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);
94 }
95
85 ts.tv_sec = (time_t)timeout; 96 ts.tv_sec = (time_t)timeout;
86 ts.tv_nsec = (long)(timeout - (ev_tstamp)ts.tv_sec) * 1e9; 97 ts.tv_nsec = (long)((timeout - (ev_tstamp)ts.tv_sec) * 1e9);
87 res = kevent (kq_fd, kq_changes, kq_changecnt, kq_events, kq_eventmax, &ts); 98 res = kevent (backend_fd, kqueue_changes, kqueue_changecnt, kqueue_events, kqueue_eventmax, &ts);
88 kq_changecnt = 0; 99 kqueue_changecnt = 0;
89 100
90 if (res < 0) 101 if (expect_false (res < 0))
102 {
103 if (errno != EINTR)
104 syserr ("(libev) kevent");
105
91 return; 106 return;
107 }
92 108
93 for (i = 0; i < res; ++i) 109 for (i = 0; i < res; ++i)
94 { 110 {
111 int fd = kqueue_events [i].ident;
112
95 if (kq_events [i].flags & EV_ERROR) 113 if (expect_false (kqueue_events [i].flags & EV_ERROR))
96 { 114 {
97 /* 115 int err = kqueue_events [i].data;
98 * Error messages that can happen, when a delete fails. 116
99 * EBADF happens when the file discriptor has been 117 /* we are only interested in errors for fds that we are interested in :) */
100 * closed, 118 if (anfds [fd].events)
101 * ENOENT when the file discriptor was closed and 119 {
102 * then reopened. 120 if (err == ENOENT) /* resubmit changes on ENOENT */
103 * EINVAL for some reasons not understood; EINVAL 121 kqueue_modify (EV_A_ fd, 0, anfds [fd].events);
104 * should not be returned ever; but FreeBSD does :-\ 122 else if (err == EBADF) /* on EBADF, we re-check the fd */
105 * An error is also indicated when a callback deletes 123 {
106 * an event we are still processing. In that case 124 if (fd_valid (fd))
107 * the data field is set to ENOENT. 125 kqueue_modify (EV_A_ fd, 0, anfds [fd].events);
108 */ 126 else
109 if (events [i].data == EBADF) 127 fd_kill (EV_A_ fd);
110 fd_kill (events [i].ident); 128 }
129 else /* on all other errors, we error out on the fd */
130 fd_kill (EV_A_ fd);
131 }
111 } 132 }
112 else 133 else
113 event ( 134 fd_event (
114 events [i].ident, 135 EV_A_
136 fd,
115 events [i].filter == EVFILT_READ ? EV_READ 137 kqueue_events [i].filter == EVFILT_READ ? EV_READ
116 : events [i].filter == EVFILT_WRITE ? EV_WRITE 138 : kqueue_events [i].filter == EVFILT_WRITE ? EV_WRITE
117 : 0 139 : 0
118 ); 140 );
119 } 141 }
120 142
121 if (expect_false (res == kq_eventmax)) 143 if (expect_false (res == kqueue_eventmax))
122 { 144 {
123 free (kq_events); 145 ev_free (kqueue_events);
124 kq_eventmax = array_roundsize (kq_events, kq_eventmax << 1); 146 kqueue_eventmax = array_nextsize (sizeof (struct kevent), kqueue_eventmax, kqueue_eventmax + 1);
125 kq_events = malloc (sizeof (struct kevent) * kq_eventmax); 147 kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);
126 } 148 }
127} 149}
128 150
129static void 151int inline_size
130kqueue_init (struct event_base *base) 152kqueue_init (EV_P_ int flags)
131{ 153{
132 struct kevent ch, ev; 154 /* Initalize the kernel queue */
155 if ((backend_fd = kqueue ()) < 0)
156 return 0;
133 157
134 /* Initalize the kernel queue */ 158 fcntl (backend_fd, F_SETFD, FD_CLOEXEC); /* not sure if necessary, hopefully doesn't hurt */
135 if ((kq_fd = kqueue ()) < 0)
136 return;
137 159
138 /* Check for Mac OS X kqueue bug. */ 160 backend_fudge = 0.;
139 ch.ident = -1; 161 backend_modify = kqueue_modify;
140 ch.filter = EVFILT_READ; 162 backend_poll = kqueue_poll;
141 ch.flags = EV_ADD;
142 163
143 /* 164 kqueue_eventmax = 64; /* initial number of events receivable per poll */
144 * If kqueue works, then kevent will succeed, and it will 165 kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);
145 * stick an error in events[0]. If kqueue is broken, then
146 * kevent will fail.
147 */
148 if (kevent (kq_fd, &ch, 1, &ev, 1, 0) != 1
149 || ev.ident != -1
150 || ev.flags != EV_ERROR)
151 {
152 /* detected broken kqueue */
153 close (kq_fd);
154 return;
155 }
156 166
157 ev_method = EVMETHOD_KQUEUE; 167 kqueue_changes = 0;
158 method_fudge = 1e-3; /* needed to compensate for kevent returning early */ 168 kqueue_changemax = 0;
159 method_modify = kq_modify; 169 kqueue_changecnt = 0;
160 method_poll = kq_poll;
161 170
162 kq_eventmax = 64; /* intiial number of events receivable per poll */ 171 return EVBACKEND_KQUEUE;
163 kq_events = malloc (sizeof (struct kevent) * kq_eventmax);
164} 172}
165 173
174void inline_size
175kqueue_destroy (EV_P)
176{
177 ev_free (kqueue_events);
178 ev_free (kqueue_changes);
179}
180
181void inline_size
182kqueue_fork (EV_P)
183{
184 close (backend_fd);
185
186 while ((backend_fd = kqueue ()) < 0)
187 syserr ("(libev) kqueue");
188
189 fcntl (backend_fd, F_SETFD, FD_CLOEXEC);
190
191 /* re-register interest in fds */
192 fd_rearm_all (EV_A);
193}
194

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