libev/ev_poll.c

/*
 * libev poll fd activity backend
 *
 * Copyright (c) 2007 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 <poll.h>

void inline_size
pollidx_init (int *base, int count)
{
  while (count--)
    *base++ = -1;
}

static void
poll_modify (EV_P_ int fd, int oev, int nev)
{
  int idx;

  if (oev == nev)
    return;

  array_needsize (int, pollidxs, pollidxmax, fd + 1, pollidx_init);

  idx = pollidxs [fd];

  if (idx < 0) /* need to allocate a new pollfd */
    {
      pollidxs [fd] = idx = pollcnt++;
      array_needsize (struct pollfd, polls, pollmax, pollcnt, EMPTY2);
      polls [idx].fd = fd;
    }

  assert (polls [idx].fd == fd);

  if (nev)
    polls [idx].events =
        (nev & EV_READ ? POLLIN : 0)
        | (nev & EV_WRITE ? POLLOUT : 0);
  else /* remove pollfd */
    {
      pollidxs [fd] = -1;

      if (expect_true (idx < --pollcnt))
        {
          polls [idx] = polls [pollcnt];
          pollidxs [polls [idx].fd] = idx;
        }
    }
}

static void
poll_poll (EV_P_ ev_tstamp timeout)
{
  int i;
  int res = poll (polls, pollcnt, (int)ceil (timeout * 1000.));

  if (expect_false (res < 0))
    {
      if (errno == EBADF)
        fd_ebadf (EV_A);
      else if (errno == ENOMEM && !syserr_cb)
        fd_enomem (EV_A);
      else if (errno != EINTR)
        syserr ("(libev) poll");
    }
  else if (res > 0)
    for (i = 0; i < pollcnt; ++i)
      if (expect_false (polls [i].revents & POLLNVAL))
        fd_kill (EV_A_ polls [i].fd);
      else
        fd_event (
          EV_A_
          polls [i].fd,
          (polls [i].revents & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0)
          | (polls [i].revents & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0)
        );
}

int inline_size
poll_init (EV_P_ int flags)
{
  backend_fudge  = 0.; /* posix says this is zero */
  backend_modify = poll_modify;
  backend_poll   = poll_poll;

  pollidxs = 0; pollidxmax = 0;
  polls    = 0; pollmax    = 0; pollcnt = 0;

  return EVBACKEND_POLL;
}

void inline_size
poll_destroy (EV_P)
{
  ev_free (pollidxs);
  ev_free (polls);
}

Revision:	1.22
Committed:	Wed Apr 9 22:33:55 2008 UTC (16 years, 1 month ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.21:	+11 -13 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	/*
2	root	1.17	* libev poll fd activity backend
3	root	1.1	*
4			* Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de>
5			* All rights reserved.
6			*
7	root	1.21	* 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	root	1.1	*
28	root	1.21	* 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	root	1.1	*/
39
40	root	1.2	#include <poll.h>
41	root	1.1
42	root	1.18	void inline_size
43	root	1.2	pollidx_init (int *base, int count)
44	root	1.1	{
45	root	1.2	while (count--)
46			*base++ = -1;
47	root	1.1	}
48
49			static void
50	root	1.3	poll_modify (EV_P_ int fd, int oev, int nev)
51	root	1.1	{
52	root	1.2	int idx;
53	root	1.6
54			if (oev == nev)
55			return;
56
57	root	1.9	array_needsize (int, pollidxs, pollidxmax, fd + 1, pollidx_init);
58	root	1.1
59	root	1.2	idx = pollidxs [fd];
60
61			if (idx < 0) /* need to allocate a new pollfd */
62			{
63	root	1.10	pollidxs [fd] = idx = pollcnt++;
64	root	1.14	array_needsize (struct pollfd, polls, pollmax, pollcnt, EMPTY2);
65	root	1.2	polls [idx].fd = fd;
66			}
67	root	1.1
68	root	1.10	assert (polls [idx].fd == fd);
69
70	root	1.2	if (nev)
71			polls [idx].events =
72			(nev & EV_READ ? POLLIN : 0)
73			\| (nev & EV_WRITE ? POLLOUT : 0);
74			else /* remove pollfd */
75			{
76	root	1.10	pollidxs [fd] = -1;
77
78	root	1.18	if (expect_true (idx < --pollcnt))
79	root	1.2	{
80			polls [idx] = polls [pollcnt];
81			pollidxs [polls [idx].fd] = idx;
82			}
83			}
84	root	1.1	}
85
86			static void
87	root	1.3	poll_poll (EV_P_ ev_tstamp timeout)
88	root	1.1	{
89	root	1.7	int i;
90	root	1.11	int res = poll (polls, pollcnt, (int)ceil (timeout * 1000.));
91	root	1.1
92	root	1.18	if (expect_false (res < 0))
93	root	1.1	{
94	root	1.2	if (errno == EBADF)
95	root	1.3	fd_ebadf (EV_A);
96	root	1.7	else if (errno == ENOMEM && !syserr_cb)
97	root	1.3	fd_enomem (EV_A);
98	root	1.7	else if (errno != EINTR)
99	root	1.8	syserr ("(libev) poll");
100	root	1.1	}
101	root	1.22	else if (res > 0)
102			for (i = 0; i < pollcnt; ++i)
103			if (expect_false (polls [i].revents & POLLNVAL))
104			fd_kill (EV_A_ polls [i].fd);
105			else
106			fd_event (
107			EV_A_
108			polls [i].fd,
109			(polls [i].revents & (POLLOUT \| POLLERR \| POLLHUP) ? EV_WRITE : 0)
110			\| (polls [i].revents & (POLLIN \| POLLERR \| POLLHUP) ? EV_READ : 0)
111			);
112	root	1.1	}
113
114	root	1.17	int inline_size
115	root	1.3	poll_init (EV_P_ int flags)
116	root	1.1	{
117	root	1.20	backend_fudge = 0.; /* posix says this is zero */
118	root	1.16	backend_modify = poll_modify;
119			backend_poll = poll_poll;
120	root	1.3
121	root	1.4	pollidxs = 0; pollidxmax = 0;
122	root	1.5	polls = 0; pollmax = 0; pollcnt = 0;
123	root	1.4
124	root	1.15	return EVBACKEND_POLL;
125	root	1.1	}
126	root	1.4
127	root	1.17	void inline_size
128	root	1.4	poll_destroy (EV_P)
129			{
130	root	1.7	ev_free (pollidxs);
131			ev_free (polls);
132	root	1.4	}
133	root	1.9