libev/ev_epoll.c

/*
 * 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 <sys/epoll.h>

static int epoll_fd = -1;

static void
epoll_modify (int fd, int oev, int nev)
{
  int mode = nev ? oev ? EPOLL_CTL_MOD : EPOLL_CTL_ADD : EPOLL_CTL_DEL;

  struct epoll_event ev;
  ev.data.fd = fd;
  ev.events =
      (nev & EV_READ ? EPOLLIN : 0)
      | (nev & EV_WRITE ? EPOLLOUT : 0);

  epoll_ctl (epoll_fd, mode, fd, &ev);
}

static void
epoll_postfork_child (void)
{
  int fd;

  epoll_fd = epoll_create (256);
  fcntl (epoll_fd, F_SETFD, FD_CLOEXEC);

  /* re-register interest in fds */
  for (fd = 0; fd < anfdmax; ++fd)
    if (anfds [fd].wev)
      epoll_modify (fd, EV_NONE, anfds [fd].wev);
}

static struct epoll_event *events;
static int eventmax;

static void
epoll_poll (ev_tstamp timeout)
{
  int eventcnt = epoll_wait (epoll_fd, events, eventmax, ceil (timeout * 1000.));
  int i;

  if (eventcnt < 0)
    return;

  for (i = 0; i < eventcnt; ++i)
    fd_event (
      events [i].data.fd,
      (events [i].events & (EPOLLOUT | EPOLLERR | EPOLLHUP) ? EV_WRITE : 0)
      | (events [i].events & (EPOLLIN | EPOLLERR | EPOLLHUP) ? EV_READ : 0)
    );

  /* if the receive array was full, increase its size */
  if (eventcnt == eventmax)
    {
      free (events);
      eventmax += eventmax >> 1;
      events = malloc (sizeof (struct epoll_event) * eventmax);
    }
}

static void
epoll_init (int flags)
{
  epoll_fd = epoll_create (256);

  if (epoll_fd < 0)
    return;

  fcntl (epoll_fd, F_SETFD, FD_CLOEXEC);

  ev_method     = EVMETHOD_EPOLL;
  method_fudge  = 1e-3; /* needed to compensate for epoll returning early */
  method_modify = epoll_modify;
  method_poll   = epoll_poll;

  eventmax = 64; /* intiial number of events receivable per poll */
  events = malloc (sizeof (struct epoll_event) * eventmax);
}

Revision:	1.6
Committed:	Wed Oct 31 20:46:44 2007 UTC (16 years, 6 months ago) by root
Content type:	text/plain
Branch:	MAIN
Changes since 1.5:	+7 -3 lines
Log Message:	stuffs
#	User	Rev	Content
1	root	1.5	/*
2			* Copyright (c) 2007 Marc Alexander Lehmann <libev@schmorp.de>
3			* All rights reserved.
4			*
5			* Redistribution and use in source and binary forms, with or without
6			* modification, are permitted provided that the following conditions are
7			* met:
8			*
9			* * Redistributions of source code must retain the above copyright
10			* notice, this list of conditions and the following disclaimer.
11			*
12			* * Redistributions in binary form must reproduce the above
13			* copyright notice, this list of conditions and the following
14			* disclaimer in the documentation and/or other materials provided
15			* with the distribution.
16			*
17			* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18			* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19			* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20			* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21			* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22			* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23			* 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
27			* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28			*/
29
30	root	1.1	#include <sys/epoll.h>
31
32			static int epoll_fd = -1;
33
34			static void
35	root	1.2	epoll_modify (int fd, int oev, int nev)
36	root	1.1	{
37	root	1.2	int mode = nev ? oev ? EPOLL_CTL_MOD : EPOLL_CTL_ADD : EPOLL_CTL_DEL;
38	root	1.1
39	root	1.2	struct epoll_event ev;
40			ev.data.fd = fd;
41			ev.events =
42			(nev & EV_READ ? EPOLLIN : 0)
43			\| (nev & EV_WRITE ? EPOLLOUT : 0);
44
45	root	1.4	epoll_ctl (epoll_fd, mode, fd, &ev);
46	root	1.1	}
47
48	root	1.6	static void
49			epoll_postfork_child (void)
50	root	1.1	{
51	root	1.2	int fd;
52	root	1.1
53			epoll_fd = epoll_create (256);
54	root	1.3	fcntl (epoll_fd, F_SETFD, FD_CLOEXEC);
55	root	1.1
56	root	1.2	/* re-register interest in fds */
57			for (fd = 0; fd < anfdmax; ++fd)
58			if (anfds [fd].wev)
59			epoll_modify (fd, EV_NONE, anfds [fd].wev);
60	root	1.1	}
61
62			static struct epoll_event *events;
63			static int eventmax;
64
65	root	1.6	static void
66			epoll_poll (ev_tstamp timeout)
67	root	1.1	{
68			int eventcnt = epoll_wait (epoll_fd, events, eventmax, ceil (timeout * 1000.));
69			int i;
70
71			if (eventcnt < 0)
72			return;
73
74			for (i = 0; i < eventcnt; ++i)
75			fd_event (
76			events [i].data.fd,
77	root	1.2	(events [i].events & (EPOLLOUT \| EPOLLERR \| EPOLLHUP) ? EV_WRITE : 0)
78			\| (events [i].events & (EPOLLIN \| EPOLLERR \| EPOLLHUP) ? EV_READ : 0)
79	root	1.1	);
80
81			/* if the receive array was full, increase its size */
82			if (eventcnt == eventmax)
83			{
84			free (events);
85			eventmax += eventmax >> 1;
86			events = malloc (sizeof (struct epoll_event) * eventmax);
87			}
88			}
89
90	root	1.6	static void
91			epoll_init (int flags)
92	root	1.1	{
93			epoll_fd = epoll_create (256);
94
95			if (epoll_fd < 0)
96	root	1.3	return;
97
98			fcntl (epoll_fd, F_SETFD, FD_CLOEXEC);
99	root	1.1
100	root	1.3	ev_method = EVMETHOD_EPOLL;
101	root	1.2	method_fudge = 1e-3; /* needed to compensate for epoll returning early */
102			method_modify = epoll_modify;
103			method_poll = epoll_poll;
104	root	1.1
105			eventmax = 64; /* intiial number of events receivable per poll */
106			events = malloc (sizeof (struct epoll_event) * eventmax);
107			}
108	root	1.6