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

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