libev/ev_port.c

/*
 * libev solaris event port backend
 *
 * Copyright (c) 2007,2008,2009,2010,2011 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.
 */

/* useful reading:
 *
 * http://bugs.opensolaris.org/view_bug.do?bug_id=6268715 (random results)
 * http://bugs.opensolaris.org/view_bug.do?bug_id=6455223 (just totally broken)
 * http://bugs.opensolaris.org/view_bug.do?bug_id=6873782 (manpage ETIME)
 * http://bugs.opensolaris.org/view_bug.do?bug_id=6874410 (implementation ETIME)
 * http://www.mail-archive.com/networking-discuss@opensolaris.org/msg11898.html ETIME vs. nget
 * http://src.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/lib/libc/port/gen/event_port.c (libc)
 * http://cvs.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/uts/common/fs/portfs/port.c#1325 (kernel)
 */

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

inline_speed
void
port_associate_and_check (EV_P_ int fd, int ev)
{
  if (0 >
      port_associate (
         backend_fd, PORT_SOURCE_FD, fd,
         (ev & EV_READ ? POLLIN : 0)
         | (ev & EV_WRITE ? POLLOUT : 0),
         0
      )
  )
    {
      if (errno == EBADFD)
        fd_kill (EV_A_ fd);
      else
        ev_syserr ("(libev) port_associate");
    }
}

static void
port_modify (EV_P_ int fd, int oev, int nev)
{
  /* we need to reassociate no matter what, as closes are
   * once more silently being discarded.
   */
  if (!nev)
    {
      if (oev)
        port_dissociate (backend_fd, PORT_SOURCE_FD, fd);
    }
  else
    port_associate_and_check (EV_A_ fd, nev);
}

static void
port_poll (EV_P_ ev_tstamp timeout)
{
  int res, i;
  struct timespec ts;
  uint_t nget = 1;

  /* we initialise this to something we will skip in the loop, as */
  /* port_getn can return with nget unchanged, but no indication */
  /* whether it was the original value or has been updated :/ */
  port_events [0].portev_source = 0;

  EV_RELEASE_CB;
  EV_TS_SET (ts, timeout);
  res = port_getn (backend_fd, port_events, port_eventmax, &nget, &ts);
  EV_ACQUIRE_CB;

  /* port_getn may or may not set nget on error */
  /* so we rely on port_events [0].portev_source not being updated */
  if (res == -1 && errno != ETIME && errno != EINTR)
    ev_syserr ("(libev) port_getn (see http://bugs.opensolaris.org/view_bug.do?bug_id=6268715, try LIBEV_FLAGS=3 env variable)");

  for (i = 0; i < nget; ++i)
    {
      if (port_events [i].portev_source == PORT_SOURCE_FD)
        {
          int fd = port_events [i].portev_object;

          fd_event (
            EV_A_
            fd,
            (port_events [i].portev_events & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0)
            | (port_events [i].portev_events & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0)
          );

          fd_change (EV_A_ fd, EV__IOFDSET);
        }
    }

  if (expect_false (nget == port_eventmax))
    {
      ev_free (port_events);
      port_eventmax = array_nextsize (sizeof (port_event_t), port_eventmax, port_eventmax + 1);
      port_events = (port_event_t *)ev_malloc (sizeof (port_event_t) * port_eventmax);
    }
}

inline_size
int
port_init (EV_P_ int flags)
{
  /* Initialize the kernel queue */
  if ((backend_fd = port_create ()) < 0)
    return 0;

  assert (("libev: PORT_SOURCE_FD must not be zero", PORT_SOURCE_FD));

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

  /* if my reading of the opensolaris kernel sources are correct, then
   * opensolaris does something very stupid: it checks if the time has already
   * elapsed and doesn't round up if that is the case,m otherwise it DOES round
   * up. Since we can't know what the case is, we need to guess by using a
   * "large enough" timeout. Normally, 1e-9 would be correct.
   */
  backend_mintime = 1e-3; /* needed to compensate for port_getn returning early */
  backend_modify  = port_modify;
  backend_poll    = port_poll;

  port_eventmax = 64; /* initial number of events receivable per poll */
  port_events = (port_event_t *)ev_malloc (sizeof (port_event_t) * port_eventmax);

  return EVBACKEND_PORT;
}

inline_size
void
port_destroy (EV_P)
{
  ev_free (port_events);
}

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

  while ((backend_fd = port_create ()) < 0)
    ev_syserr ("(libev) port");

  fcntl (backend_fd, F_SETFD, FD_CLOEXEC);

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

Revision:	1.29
Committed:	Thu Feb 18 04:48:05 2016 UTC (8 years, 2 months ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-4_23, rel-4_25, rel-4_24
Changes since 1.28:	+8 -4 lines
Log Message:	* empty log message *
#	Content
1	/*
2	* libev solaris event port backend
3	*
4	* Copyright (c) 2007,2008,2009,2010,2011 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	/* useful reading:
41	*
42	* http://bugs.opensolaris.org/view_bug.do?bug_id=6268715 (random results)
43	* http://bugs.opensolaris.org/view_bug.do?bug_id=6455223 (just totally broken)
44	* http://bugs.opensolaris.org/view_bug.do?bug_id=6873782 (manpage ETIME)
45	* http://bugs.opensolaris.org/view_bug.do?bug_id=6874410 (implementation ETIME)
46	* http://www.mail-archive.com/networking-discuss@opensolaris.org/msg11898.html ETIME vs. nget
47	* http://src.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/lib/libc/port/gen/event_port.c (libc)
48	* http://cvs.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/uts/common/fs/portfs/port.c#1325 (kernel)
49	*/
50
51	#include <sys/types.h>
52	#include <sys/time.h>
53	#include <poll.h>
54	#include <port.h>
55	#include <string.h>
56	#include <errno.h>
57
58	inline_speed
59	void
60	port_associate_and_check (EV_P_ int fd, int ev)
61	{
62	if (0 >
63	port_associate (
64	backend_fd, PORT_SOURCE_FD, fd,
65	(ev & EV_READ ? POLLIN : 0)
66	\| (ev & EV_WRITE ? POLLOUT : 0),
67	0
68	)
69	)
70	{
71	if (errno == EBADFD)
72	fd_kill (EV_A_ fd);
73	else
74	ev_syserr ("(libev) port_associate");
75	}
76	}
77
78	static void
79	port_modify (EV_P_ int fd, int oev, int nev)
80	{
81	/* we need to reassociate no matter what, as closes are
82	* once more silently being discarded.
83	*/
84	if (!nev)
85	{
86	if (oev)
87	port_dissociate (backend_fd, PORT_SOURCE_FD, fd);
88	}
89	else
90	port_associate_and_check (EV_A_ fd, nev);
91	}
92
93	static void
94	port_poll (EV_P_ ev_tstamp timeout)
95	{
96	int res, i;
97	struct timespec ts;
98	uint_t nget = 1;
99
100	/* we initialise this to something we will skip in the loop, as */
101	/* port_getn can return with nget unchanged, but no indication */
102	/* whether it was the original value or has been updated :/ */
103	port_events [0].portev_source = 0;
104
105	EV_RELEASE_CB;
106	EV_TS_SET (ts, timeout);
107	res = port_getn (backend_fd, port_events, port_eventmax, &nget, &ts);
108	EV_ACQUIRE_CB;
109
110	/* port_getn may or may not set nget on error */
111	/* so we rely on port_events [0].portev_source not being updated */
112	if (res == -1 && errno != ETIME && errno != EINTR)
113	ev_syserr ("(libev) port_getn (see http://bugs.opensolaris.org/view_bug.do?bug_id=6268715, try LIBEV_FLAGS=3 env variable)");
114
115	for (i = 0; i < nget; ++i)
116	{
117	if (port_events [i].portev_source == PORT_SOURCE_FD)
118	{
119	int fd = port_events [i].portev_object;
120
121	fd_event (
122	EV_A_
123	fd,
124	(port_events [i].portev_events & (POLLOUT \| POLLERR \| POLLHUP) ? EV_WRITE : 0)
125	\| (port_events [i].portev_events & (POLLIN \| POLLERR \| POLLHUP) ? EV_READ : 0)
126	);
127
128	fd_change (EV_A_ fd, EV__IOFDSET);
129	}
130	}
131
132	if (expect_false (nget == port_eventmax))
133	{
134	ev_free (port_events);
135	port_eventmax = array_nextsize (sizeof (port_event_t), port_eventmax, port_eventmax + 1);
136	port_events = (port_event_t )ev_malloc (sizeof (port_event_t) port_eventmax);
137	}
138	}
139
140	inline_size
141	int
142	port_init (EV_P_ int flags)
143	{
144	/* Initialize the kernel queue */
145	if ((backend_fd = port_create ()) < 0)
146	return 0;
147
148	assert (("libev: PORT_SOURCE_FD must not be zero", PORT_SOURCE_FD));
149
150	fcntl (backend_fd, F_SETFD, FD_CLOEXEC); /* not sure if necessary, hopefully doesn't hurt */
151
152	/* if my reading of the opensolaris kernel sources are correct, then
153	* opensolaris does something very stupid: it checks if the time has already
154	* elapsed and doesn't round up if that is the case,m otherwise it DOES round
155	* up. Since we can't know what the case is, we need to guess by using a
156	* "large enough" timeout. Normally, 1e-9 would be correct.
157	*/
158	backend_mintime = 1e-3; /* needed to compensate for port_getn returning early */
159	backend_modify = port_modify;
160	backend_poll = port_poll;
161
162	port_eventmax = 64; /* initial number of events receivable per poll */
163	port_events = (port_event_t )ev_malloc (sizeof (port_event_t) port_eventmax);
164
165	return EVBACKEND_PORT;
166	}
167
168	inline_size
169	void
170	port_destroy (EV_P)
171	{
172	ev_free (port_events);
173	}
174
175	inline_size
176	void
177	port_fork (EV_P)
178	{
179	close (backend_fd);
180
181	while ((backend_fd = port_create ()) < 0)
182	ev_syserr ("(libev) port");
183
184	fcntl (backend_fd, F_SETFD, FD_CLOEXEC);
185
186	/* re-register interest in fds */
187	fd_rearm_all (EV_A);
188	}
189