libev/ev_poll.c

/*
 * libev epoll 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
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *
 *     * 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 COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, 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 OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <poll.h>

static void
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 (pollidxs, pollidxmax, fd + 1, pollidx_init);

  idx = pollidxs [fd];

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

  if (nev)
    polls [idx].events =
        (nev & EV_READ ? POLLIN : 0)
        | (nev & EV_WRITE ? POLLOUT : 0);
  else /* remove pollfd */
    {
      if (idx < pollcnt--)
        {
          pollidxs [fd] = -1;
          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, ceil (timeout * 1000.));

  if (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");

      return;
    }

  for (i = 0; i < pollcnt; ++i)
    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)
    );
}

static int
poll_init (EV_P_ int flags)
{
  method_fudge  = 1e-3; /* needed to compensate for select returning early, very conservative */
  method_modify = poll_modify;
  method_poll   = poll_poll;

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

  return EVMETHOD_POLL;
}

static void
poll_destroy (EV_P)
{
  ev_free (pollidxs);
  ev_free (polls);
}
Revision:	1.8
Committed:	Tue Nov 6 00:52:33 2007 UTC (16 years, 6 months ago) by root
Content type:	text/plain
Branch:	MAIN
CVS Tags:	rel-0_5
Changes since 1.7:	+1 -1 lines
Log Message:	better fork
#	User	Rev	Content
1	root	1.1	/*
2			* libev epoll fd activity backend
3			*
4			* Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de>
5			* All rights reserved.
6			*
7			* Redistribution and use in source and binary forms, with or without
8			* modification, are permitted provided that the following conditions are
9			* met:
10			*
11			* * Redistributions of source code must retain the above copyright
12			* notice, this list of conditions and the following disclaimer.
13			*
14			* * Redistributions in binary form must reproduce the above
15			* copyright notice, this list of conditions and the following
16			* disclaimer in the documentation and/or other materials provided
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,
24			* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25			* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26			* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27			* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28			* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29			* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30			*/
31
32	root	1.2	#include <poll.h>
33	root	1.1
34			static void
35	root	1.2	pollidx_init (int *base, int count)
36	root	1.1	{
37	root	1.2	while (count--)
38			*base++ = -1;
39	root	1.1	}
40
41			static void
42	root	1.3	poll_modify (EV_P_ int fd, int oev, int nev)
43	root	1.1	{
44	root	1.2	int idx;
45	root	1.6
46			if (oev == nev)
47			return;
48
49	root	1.2	array_needsize (pollidxs, pollidxmax, fd + 1, pollidx_init);
50	root	1.1
51	root	1.2	idx = pollidxs [fd];
52
53			if (idx < 0) /* need to allocate a new pollfd */
54			{
55			idx = pollcnt++;
56			array_needsize (polls, pollmax, pollcnt, );
57			polls [idx].fd = fd;
58			}
59	root	1.1
60	root	1.2	if (nev)
61			polls [idx].events =
62			(nev & EV_READ ? POLLIN : 0)
63			\| (nev & EV_WRITE ? POLLOUT : 0);
64			else /* remove pollfd */
65			{
66			if (idx < pollcnt--)
67			{
68			pollidxs [fd] = -1;
69			polls [idx] = polls [pollcnt];
70			pollidxs [polls [idx].fd] = idx;
71			}
72			}
73	root	1.1	}
74
75			static void
76	root	1.3	poll_poll (EV_P_ ev_tstamp timeout)
77	root	1.1	{
78	root	1.7	int i;
79	root	1.2	int res = poll (polls, pollcnt, ceil (timeout * 1000.));
80	root	1.1
81	root	1.7	if (res < 0)
82	root	1.1	{
83	root	1.2	if (errno == EBADF)
84	root	1.3	fd_ebadf (EV_A);
85	root	1.7	else if (errno == ENOMEM && !syserr_cb)
86	root	1.3	fd_enomem (EV_A);
87	root	1.7	else if (errno != EINTR)
88	root	1.8	syserr ("(libev) poll");
89	root	1.7
90			return;
91	root	1.1	}
92	root	1.7
93			for (i = 0; i < pollcnt; ++i)
94			fd_event (
95			EV_A_
96			polls [i].fd,
97			(polls [i].revents & (POLLOUT \| POLLERR \| POLLHUP) ? EV_WRITE : 0)
98			\| (polls [i].revents & (POLLIN \| POLLERR \| POLLHUP) ? EV_READ : 0)
99			);
100	root	1.1	}
101
102	root	1.3	static int
103			poll_init (EV_P_ int flags)
104	root	1.1	{
105	root	1.2	method_fudge = 1e-3; /* needed to compensate for select returning early, very conservative */
106			method_modify = poll_modify;
107			method_poll = poll_poll;
108	root	1.3
109	root	1.4	pollidxs = 0; pollidxmax = 0;
110	root	1.5	polls = 0; pollmax = 0; pollcnt = 0;
111	root	1.4
112	root	1.3	return EVMETHOD_POLL;
113	root	1.1	}
114	root	1.4
115			static void
116			poll_destroy (EV_P)
117			{
118	root	1.7	ev_free (pollidxs);
119			ev_free (polls);
120	root	1.4	}