libev/ev_kqueue.c

/*
 * libev kqueue backend
 *
 * Copyright (c) 2007,2008,2009 Marc Alexander Lehmann <libev@schmorp.de>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modifica-
 * tion, are permitted provided that the following conditions are met:
 * 
 *   1.  Redistributions of source code must retain the above copyright notice,
 *       this list of conditions and the following disclaimer.
 * 
 *   2.  Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MER-
 * CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO
 * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPE-
 * CIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTH-
 * ERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Alternatively, the contents of this file may be used under the terms of
 * the GNU General Public License ("GPL") version 2 or any later version,
 * in which case the provisions of the GPL are applicable instead of
 * the above. If you wish to allow the use of your version of this file
 * only under the terms of the GPL and not to allow others to use your
 * version of this file under the BSD license, indicate your decision
 * by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL. If you do not delete the
 * provisions above, a recipient may use your version of this file under
 * either the BSD or the GPL.
 */

#include <sys/types.h>
#include <sys/time.h>
#include <sys/event.h>
#include <string.h>
#include <errno.h>

void inline_speed
kqueue_change (EV_P_ int fd, int filter, int flags, int fflags)
{
  ++kqueue_changecnt;
  array_needsize (struct kevent, kqueue_changes, kqueue_changemax, kqueue_changecnt, EMPTY2);

  EV_SET (&kqueue_changes [kqueue_changecnt - 1], fd, filter, flags, fflags, 0, 0);
}

/* OS X at least needs this */
#ifndef EV_ENABLE
# define EV_ENABLE 0
#endif
#ifndef NOTE_EOF
# define NOTE_EOF 0
#endif

static void
kqueue_modify (EV_P_ int fd, int oev, int nev)
{
  if (oev != nev)
    {
      if (oev & EV_READ)
        kqueue_change (EV_A_ fd, EVFILT_READ , EV_DELETE, 0);

      if (oev & EV_WRITE)
        kqueue_change (EV_A_ fd, EVFILT_WRITE, EV_DELETE, 0);
    }

  /* to detect close/reopen reliably, we have to re-add */
  /* event requests even when oev == nev */

  if (nev & EV_READ)
    kqueue_change (EV_A_ fd, EVFILT_READ , EV_ADD | EV_ENABLE, NOTE_EOF);

  if (nev & EV_WRITE)
    kqueue_change (EV_A_ fd, EVFILT_WRITE, EV_ADD | EV_ENABLE, NOTE_EOF);
}

static void
kqueue_poll (EV_P_ ev_tstamp timeout)
{
  int res, i;
  struct timespec ts;

  /* need to resize so there is enough space for errors */
  if (kqueue_changecnt > kqueue_eventmax)
    {
      ev_free (kqueue_events);
      kqueue_eventmax = array_nextsize (sizeof (struct kevent), kqueue_eventmax, kqueue_changecnt);
      kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);
    }

  EV_RELEASE_CB;
  ts.tv_sec  = (time_t)timeout;
  ts.tv_nsec = (long)((timeout - (ev_tstamp)ts.tv_sec) * 1e9);
  res = kevent (backend_fd, kqueue_changes, kqueue_changecnt, kqueue_events, kqueue_eventmax, &ts);
  EV_ACQUIRE_CB;
  kqueue_changecnt = 0;

  if (expect_false (res < 0))
    { 
      if (errno != EINTR)
        ev_syserr ("(libev) kevent");

      return;
    } 

  for (i = 0; i < res; ++i)
    {
      int fd = kqueue_events [i].ident;

      if (expect_false (kqueue_events [i].flags & EV_ERROR))
        {
          int err = kqueue_events [i].data;

          /* we are only interested in errors for fds that we are interested in :) */
          if (anfds [fd].events)
            {
              if (err == ENOENT) /* resubmit changes on ENOENT */
                kqueue_modify (EV_A_ fd, 0, anfds [fd].events);
              else if (err == EBADF) /* on EBADF, we re-check the fd */
                {
                  if (fd_valid (fd))
                    kqueue_modify (EV_A_ fd, 0, anfds [fd].events);
                  else
                    fd_kill (EV_A_ fd);
                }
              else /* on all other errors, we error out on the fd */
                fd_kill (EV_A_ fd);
            }
        }
      else
        fd_event (
          EV_A_
          fd,
          kqueue_events [i].filter == EVFILT_READ ? EV_READ
          : kqueue_events [i].filter == EVFILT_WRITE ? EV_WRITE
          : 0
        );
    }

  if (expect_false (res == kqueue_eventmax))
    {
      ev_free (kqueue_events);
      kqueue_eventmax = array_nextsize (sizeof (struct kevent), kqueue_eventmax, kqueue_eventmax + 1);
      kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);
    }
}

int inline_size
kqueue_init (EV_P_ int flags)
{
  /* Initalize the kernel queue */
  if ((backend_fd = kqueue ()) < 0)
    return 0;

  fcntl (backend_fd, F_SETFD, FD_CLOEXEC); /* not sure if necessary, hopefully doesn't hurt */

  backend_fudge  = 0.;
  backend_modify = kqueue_modify;
  backend_poll   = kqueue_poll;

  kqueue_eventmax = 64; /* initial number of events receivable per poll */
  kqueue_events = (struct kevent *)ev_malloc (sizeof (struct kevent) * kqueue_eventmax);

  kqueue_changes   = 0;
  kqueue_changemax = 0;
  kqueue_changecnt = 0;

  return EVBACKEND_KQUEUE;
}

void inline_size
kqueue_destroy (EV_P)
{
  ev_free (kqueue_events);
  ev_free (kqueue_changes);
}

void inline_size
kqueue_fork (EV_P)
{
  close (backend_fd);

  while ((backend_fd = kqueue ()) < 0)
    ev_syserr ("(libev) kqueue");

  fcntl (backend_fd, F_SETFD, FD_CLOEXEC);

  /* re-register interest in fds */
  fd_rearm_all (EV_A);
}

Revision:	1.42
Committed:	Sat Mar 27 02:26:27 2010 UTC (14 years, 1 month ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.41:	+6 -2 lines
Log Message:	* empty log message *
#	Content
1	/*
2	* libev kqueue backend
3	*
4	* Copyright (c) 2007,2008,2009 Marc Alexander Lehmann <libev@schmorp.de>
5	* All rights reserved.
6	*
7	* Redistribution and use in source and binary forms, with or without modifica-
8	* tion, are permitted provided that the following conditions 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.
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.
38	*/
39
40	#include <sys/types.h>
41	#include <sys/time.h>
42	#include <sys/event.h>
43	#include <string.h>
44	#include <errno.h>
45
46	void inline_speed
47	kqueue_change (EV_P_ int fd, int filter, int flags, int fflags)
48	{
49	++kqueue_changecnt;
50	array_needsize (struct kevent, kqueue_changes, kqueue_changemax, kqueue_changecnt, EMPTY2);
51
52	EV_SET (&kqueue_changes [kqueue_changecnt - 1], fd, filter, flags, fflags, 0, 0);
53	}
54
55	/* OS X at least needs this */
56	#ifndef EV_ENABLE
57	# define EV_ENABLE 0
58	#endif
59	#ifndef NOTE_EOF
60	# define NOTE_EOF 0
61	#endif
62
63	static void
64	kqueue_modify (EV_P_ int fd, int oev, int nev)
65	{
66	if (oev != nev)
67	{
68	if (oev & EV_READ)
69	kqueue_change (EV_A_ fd, EVFILT_READ , EV_DELETE, 0);
70
71	if (oev & EV_WRITE)
72	kqueue_change (EV_A_ fd, EVFILT_WRITE, EV_DELETE, 0);
73	}
74
75	/* to detect close/reopen reliably, we have to re-add */
76	/* event requests even when oev == nev */
77
78	if (nev & EV_READ)
79	kqueue_change (EV_A_ fd, EVFILT_READ , EV_ADD \| EV_ENABLE, NOTE_EOF);
80
81	if (nev & EV_WRITE)
82	kqueue_change (EV_A_ fd, EVFILT_WRITE, EV_ADD \| EV_ENABLE, NOTE_EOF);
83	}
84
85	static void
86	kqueue_poll (EV_P_ ev_tstamp timeout)
87	{
88	int res, i;
89	struct timespec ts;
90
91	/* need to resize so there is enough space for errors */
92	if (kqueue_changecnt > kqueue_eventmax)
93	{
94	ev_free (kqueue_events);
95	kqueue_eventmax = array_nextsize (sizeof (struct kevent), kqueue_eventmax, kqueue_changecnt);
96	kqueue_events = (struct kevent )ev_malloc (sizeof (struct kevent) kqueue_eventmax);
97	}
98
99	EV_RELEASE_CB;
100	ts.tv_sec = (time_t)timeout;
101	ts.tv_nsec = (long)((timeout - (ev_tstamp)ts.tv_sec) * 1e9);
102	res = kevent (backend_fd, kqueue_changes, kqueue_changecnt, kqueue_events, kqueue_eventmax, &ts);
103	EV_ACQUIRE_CB;
104	kqueue_changecnt = 0;
105
106	if (expect_false (res < 0))
107	{
108	if (errno != EINTR)
109	ev_syserr ("(libev) kevent");
110
111	return;
112	}
113
114	for (i = 0; i < res; ++i)
115	{
116	int fd = kqueue_events [i].ident;
117
118	if (expect_false (kqueue_events [i].flags & EV_ERROR))
119	{
120	int err = kqueue_events [i].data;
121
122	/* we are only interested in errors for fds that we are interested in :) */
123	if (anfds [fd].events)
124	{
125	if (err == ENOENT) /* resubmit changes on ENOENT */
126	kqueue_modify (EV_A_ fd, 0, anfds [fd].events);
127	else if (err == EBADF) /* on EBADF, we re-check the fd */
128	{
129	if (fd_valid (fd))
130	kqueue_modify (EV_A_ fd, 0, anfds [fd].events);
131	else
132	fd_kill (EV_A_ fd);
133	}
134	else /* on all other errors, we error out on the fd */
135	fd_kill (EV_A_ fd);
136	}
137	}
138	else
139	fd_event (
140	EV_A_
141	fd,
142	kqueue_events [i].filter == EVFILT_READ ? EV_READ
143	: kqueue_events [i].filter == EVFILT_WRITE ? EV_WRITE
144	: 0
145	);
146	}
147
148	if (expect_false (res == kqueue_eventmax))
149	{
150	ev_free (kqueue_events);
151	kqueue_eventmax = array_nextsize (sizeof (struct kevent), kqueue_eventmax, kqueue_eventmax + 1);
152	kqueue_events = (struct kevent )ev_malloc (sizeof (struct kevent) kqueue_eventmax);
153	}
154	}
155
156	int inline_size
157	kqueue_init (EV_P_ int flags)
158	{
159	/* Initalize the kernel queue */
160	if ((backend_fd = kqueue ()) < 0)
161	return 0;
162
163	fcntl (backend_fd, F_SETFD, FD_CLOEXEC); /* not sure if necessary, hopefully doesn't hurt */
164
165	backend_fudge = 0.;
166	backend_modify = kqueue_modify;
167	backend_poll = kqueue_poll;
168
169	kqueue_eventmax = 64; /* initial number of events receivable per poll */
170	kqueue_events = (struct kevent )ev_malloc (sizeof (struct kevent) kqueue_eventmax);
171
172	kqueue_changes = 0;
173	kqueue_changemax = 0;
174	kqueue_changecnt = 0;
175
176	return EVBACKEND_KQUEUE;
177	}
178
179	void inline_size
180	kqueue_destroy (EV_P)
181	{
182	ev_free (kqueue_events);
183	ev_free (kqueue_changes);
184	}
185
186	void inline_size
187	kqueue_fork (EV_P)
188	{
189	close (backend_fd);
190
191	while ((backend_fd = kqueue ()) < 0)
192	ev_syserr ("(libev) kqueue");
193
194	fcntl (backend_fd, F_SETFD, FD_CLOEXEC);
195
196	/* re-register interest in fds */
197	fd_rearm_all (EV_A);
198	}
199