1 |
/* |
2 |
* Copyright 2007 Marc Alexander Lehmann <libev@schmorp.de> |
3 |
* Copyright 2000-2002 Niels Provos <provos@citi.umich.edu> |
4 |
* All rights reserved. |
5 |
* |
6 |
* Redistribution and use in source and binary forms, with or without |
7 |
* modification, are permitted provided that the following conditions |
8 |
* are met: |
9 |
* |
10 |
* 1. Redistributions of source code must retain the above copyright |
11 |
* notice, this list of conditions and the following disclaimer. |
12 |
* 2. Redistributions in binary form must reproduce the above copyright |
13 |
* notice, this list of conditions and the following disclaimer in the |
14 |
* documentation and/or other materials provided with the distribution. |
15 |
* 3. The name of the author may not be used to endorse or promote products |
16 |
* derived from this software without specific prior written permission. |
17 |
* |
18 |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
19 |
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
20 |
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
21 |
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
22 |
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
23 |
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
24 |
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
25 |
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
26 |
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
27 |
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
28 |
*/ |
29 |
|
30 |
#include <sys/types.h> |
31 |
#include <sys/time.h> |
32 |
#include <sys/queue.h> |
33 |
#include <sys/event.h> |
34 |
#include <string.h> |
35 |
#include <errno.h> |
36 |
|
37 |
static void |
38 |
kqueue_change (EV_P_ int fd, int filter, int flags, int fflags) |
39 |
{ |
40 |
struct kevent *ke; |
41 |
|
42 |
++kqueue_changecnt; |
43 |
array_needsize (struct kevent, kqueue_changes, kqueue_changemax, kqueue_changecnt, EMPTY2); |
44 |
|
45 |
ke = &kqueue_changes [kqueue_changecnt - 1]; |
46 |
memset (ke, 0, sizeof (struct kevent)); |
47 |
ke->ident = fd; |
48 |
ke->filter = filter; |
49 |
ke->flags = flags; |
50 |
ke->fflags = fflags; |
51 |
} |
52 |
|
53 |
#ifndef NOTE_EOF |
54 |
# define NOTE_EOF 0 |
55 |
#endif |
56 |
|
57 |
static void |
58 |
kqueue_modify (EV_P_ int fd, int oev, int nev) |
59 |
{ |
60 |
/* to detect close/reopen reliably, we have to remove and re-add */ |
61 |
/* event requests even when oev == nev */ |
62 |
|
63 |
if (oev & EV_READ) |
64 |
kqueue_change (EV_A_ fd, EVFILT_READ, EV_DELETE, 0); |
65 |
|
66 |
if (oev & EV_WRITE) |
67 |
kqueue_change (EV_A_ fd, EVFILT_WRITE, EV_DELETE, 0); |
68 |
|
69 |
if (nev & EV_READ) |
70 |
kqueue_change (EV_A_ fd, EVFILT_READ, EV_ADD, NOTE_EOF); |
71 |
|
72 |
if (nev & EV_WRITE) |
73 |
kqueue_change (EV_A_ fd, EVFILT_WRITE, EV_ADD, NOTE_EOF); |
74 |
} |
75 |
|
76 |
static void |
77 |
kqueue_poll (EV_P_ ev_tstamp timeout) |
78 |
{ |
79 |
int res, i; |
80 |
struct timespec ts; |
81 |
|
82 |
/* need to resize so there is enough space for errors */ |
83 |
if (kqueue_changecnt > kqueue_eventmax) |
84 |
{ |
85 |
ev_free (kqueue_events); |
86 |
kqueue_eventmax = array_roundsize (struct kevent, kqueue_changecnt); |
87 |
kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax); |
88 |
} |
89 |
|
90 |
ts.tv_sec = (time_t)timeout; |
91 |
ts.tv_nsec = (long)(timeout - (ev_tstamp)ts.tv_sec) * 1e9; |
92 |
res = kevent (kqueue_fd, kqueue_changes, kqueue_changecnt, kqueue_events, kqueue_eventmax, &ts); |
93 |
kqueue_changecnt = 0; |
94 |
|
95 |
if (res < 0) |
96 |
{ |
97 |
if (errno != EINTR) |
98 |
syserr ("(libev) kevent"); |
99 |
|
100 |
return; |
101 |
} |
102 |
|
103 |
for (i = 0; i < res; ++i) |
104 |
{ |
105 |
int fd = kqueue_events [i].ident; |
106 |
|
107 |
if (kqueue_events [i].flags & EV_ERROR) |
108 |
{ |
109 |
int err = kqueue_events [i].data; |
110 |
|
111 |
/* |
112 |
* errors that may happen |
113 |
* EBADF happens when the file discriptor has been |
114 |
* closed, |
115 |
* ENOENT when the file descriptor was closed and |
116 |
* then reopened. |
117 |
* EINVAL for some reasons not understood; EINVAL |
118 |
* should not be returned ever; but FreeBSD does :-\ |
119 |
*/ |
120 |
|
121 |
/* we are only interested in errors for fds that we are interested in :) */ |
122 |
if (anfds [fd].events) |
123 |
{ |
124 |
if (err == ENOENT) /* resubmit changes on ENOENT */ |
125 |
kqueue_modify (EV_A_ fd, 0, anfds [fd].events); |
126 |
else if (err == EBADF) /* on EBADF, we re-check the fd */ |
127 |
{ |
128 |
if (fd_valid (fd)) |
129 |
kqueue_modify (EV_A_ fd, 0, anfds [fd].events); |
130 |
else |
131 |
fd_kill (EV_A_ fd); |
132 |
} |
133 |
else /* on all other errors, we error out on the fd */ |
134 |
fd_kill (EV_A_ fd); |
135 |
} |
136 |
} |
137 |
else |
138 |
fd_event ( |
139 |
EV_A_ |
140 |
fd, |
141 |
kqueue_events [i].filter == EVFILT_READ ? EV_READ |
142 |
: kqueue_events [i].filter == EVFILT_WRITE ? EV_WRITE |
143 |
: 0 |
144 |
); |
145 |
} |
146 |
|
147 |
if (expect_false (res == kqueue_eventmax)) |
148 |
{ |
149 |
ev_free (kqueue_events); |
150 |
kqueue_eventmax = array_roundsize (struct kevent, kqueue_eventmax << 1); |
151 |
kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax); |
152 |
} |
153 |
} |
154 |
|
155 |
static int |
156 |
kqueue_init (EV_P_ int flags) |
157 |
{ |
158 |
struct kevent ch, ev; |
159 |
|
160 |
/* Initalize the kernel queue */ |
161 |
if ((kqueue_fd = kqueue ()) < 0) |
162 |
return 0; |
163 |
|
164 |
fcntl (kqueue_fd, F_SETFD, FD_CLOEXEC); /* not sure if necessary, hopefully doesn't hurt */ |
165 |
|
166 |
/* Check for Mac OS X kqueue bug. */ |
167 |
ch.ident = -1; |
168 |
ch.filter = EVFILT_READ; |
169 |
ch.flags = EV_ADD; |
170 |
|
171 |
/* |
172 |
* If kqueue works, then kevent will succeed, and it will |
173 |
* stick an error in ev. If kqueue is broken, then |
174 |
* kevent will fail. |
175 |
*/ |
176 |
if (kevent (kqueue_fd, &ch, 1, &ev, 1, 0) != 1 |
177 |
|| ev.ident != -1 |
178 |
|| ev.flags != EV_ERROR) |
179 |
{ |
180 |
/* detected broken kqueue */ |
181 |
close (kqueue_fd); |
182 |
return 0; |
183 |
} |
184 |
|
185 |
method_fudge = 1e-3; /* needed to compensate for kevent returning early */ |
186 |
method_modify = kqueue_modify; |
187 |
method_poll = kqueue_poll; |
188 |
|
189 |
kqueue_eventmax = 64; /* intiial number of events receivable per poll */ |
190 |
kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax); |
191 |
|
192 |
kqueue_changes = 0; |
193 |
kqueue_changemax = 0; |
194 |
kqueue_changecnt = 0; |
195 |
|
196 |
return EVMETHOD_KQUEUE; |
197 |
} |
198 |
|
199 |
static void |
200 |
kqueue_destroy (EV_P) |
201 |
{ |
202 |
close (kqueue_fd); |
203 |
|
204 |
ev_free (kqueue_events); |
205 |
ev_free (kqueue_changes); |
206 |
} |
207 |
|
208 |
static void |
209 |
kqueue_fork (EV_P) |
210 |
{ |
211 |
close (kqueue_fd); |
212 |
|
213 |
while ((kqueue_fd = kqueue ()) < 0) |
214 |
syserr ("(libev) kqueue"); |
215 |
|
216 |
fcntl (kqueue_fd, F_SETFD, FD_CLOEXEC); |
217 |
|
218 |
/* re-register interest in fds */ |
219 |
fd_rearm_all (EV_A); |
220 |
} |
221 |
|