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Comparing libev/ev_epoll.c (file contents):
Revision 1.1 by root, Tue Oct 30 20:59:31 2007 UTC vs.
Revision 1.22 by root, Tue Nov 6 01:17:16 2007 UTC

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
1#include <sys/epoll.h> 32#include <sys/epoll.h>
2 33
3static int epoll_fd = -1; 34static void
35epoll_modify (EV_P_ int fd, int oev, int nev)
36{
37 int mode = nev ? oev ? EPOLL_CTL_MOD : EPOLL_CTL_ADD : EPOLL_CTL_DEL;
38
39 struct epoll_event ev;
40 ev.data.u64 = fd; /* use u64 to fully initialise the struct, for nicer strace etc. */
41 ev.events =
42 (nev & EV_READ ? EPOLLIN : 0)
43 | (nev & EV_WRITE ? EPOLLOUT : 0);
44
45 if (epoll_ctl (epoll_fd, mode, fd, &ev))
46 if (errno != ENOENT /* on ENOENT the fd went away, so try to do the right thing */
47 || (nev && epoll_ctl (epoll_fd, EPOLL_CTL_ADD, fd, &ev)))
48 fd_kill (EV_A_ fd);
49}
4 50
5static void 51static void
6epoll_reify_fd (int fd) 52epoll_poll (EV_P_ ev_tstamp timeout)
7{ 53{
8 ANFD *anfd = anfds + fd; 54 int i;
9 struct ev_io *w; 55 int eventcnt = epoll_wait (epoll_fd, epoll_events, epoll_eventmax, ceil (timeout * 1000.));
10 56
11 int wev = 0; 57 if (eventcnt < 0)
58 {
59 if (errno != EINTR)
60 syserr ("(libev) epoll_wait");
12 61
13 for (w = anfd->head; w; w = w->next) 62 return;
14 wev |= w->events; 63 }
15 64
16 if (anfd->wev != wev) 65 for (i = 0; i < eventcnt; ++i)
66 fd_event (
67 EV_A_
68 epoll_events [i].data.u64,
69 (epoll_events [i].events & (EPOLLOUT | EPOLLERR | EPOLLHUP) ? EV_WRITE : 0)
70 | (epoll_events [i].events & (EPOLLIN | EPOLLERR | EPOLLHUP) ? EV_READ : 0)
71 );
72
73 /* if the receive array was full, increase its size */
74 if (expect_false (eventcnt == epoll_eventmax))
17 { 75 {
18 int mode = wev ? anfd->wev ? EPOLL_CTL_MOD : EPOLL_CTL_ADD : EPOLL_CTL_DEL; 76 ev_free (epoll_events);
19 struct epoll_event ev; 77 epoll_eventmax = array_roundsize (epoll_events, epoll_eventmax << 1);
20 ev.events = wev; 78 epoll_events = ev_malloc (sizeof (struct epoll_event) * epoll_eventmax);
21 ev.data.fd = fd;
22 fprintf (stderr, "reify %d,%d,%d m%d (r=%d)\n", fd, anfd->wev, wev, mode,//D
23 epoll_ctl (epoll_fd, mode, fd, &ev)
24 );//D
25 anfd->wev = wev;
26 } 79 }
27} 80}
28 81
29void epoll_postfork_child (void) 82static int
30{
31 int i;
32
33 epoll_fd = epoll_create (256);
34
35 for (i = 0; i < anfdmax; ++i)
36 epoll_reify_fd (i);
37}
38
39static void epoll_reify (void)
40{
41 int i;
42 for (i = 0; i < fdchangecnt; ++i)
43 epoll_reify_fd (fdchanges [i]);
44}
45
46static struct epoll_event *events;
47static int eventmax;
48
49static void epoll_poll (ev_tstamp timeout)
50{
51 int eventcnt = epoll_wait (epoll_fd, events, eventmax, ceil (timeout * 1000.));
52 int i;
53
54 if (eventcnt < 0)
55 return;
56
57 for (i = 0; i < eventcnt; ++i)
58 fd_event (
59 events [i].data.fd,
60 (events [i].events & (EPOLLOUT | EPOLLERR | EPOLLHUP | EPOLLPRI) ? EV_WRITE : 0)
61 | (events [i].events & (EPOLLIN | EPOLLERR | EPOLLHUP) ? EV_READ : 0)
62 );
63
64 /* if the receive array was full, increase its size */
65 if (eventcnt == eventmax)
66 {
67 free (events);
68 eventmax += eventmax >> 1;
69 events = malloc (sizeof (struct epoll_event) * eventmax);
70 }
71}
72
73int epoll_init (int flags) 83epoll_init (EV_P_ int flags)
74{ 84{
75 epoll_fd = epoll_create (256); 85 epoll_fd = epoll_create (256);
76 86
77 if (epoll_fd < 0) 87 if (epoll_fd < 0)
78 return 0; 88 return 0;
79 89
80 ev_method = EVMETHOD_EPOLL; 90 fcntl (epoll_fd, F_SETFD, FD_CLOEXEC);
81 method_fudge = 1e-3; /* needed to compensate fro epoll returning early */
82 method_reify = epoll_reify;
83 method_poll = epoll_poll;
84 91
85 eventmax = 64; /* intiial number of events receivable per poll */ 92 method_fudge = 1e-3; /* needed to compensate for epoll returning early */
86 events = malloc (sizeof (struct epoll_event) * eventmax); 93 method_modify = epoll_modify;
94 method_poll = epoll_poll;
87 95
88 return 1; 96 epoll_eventmax = 64; /* intiial number of events receivable per poll */
97 epoll_events = ev_malloc (sizeof (struct epoll_event) * epoll_eventmax);
98
99 return EVMETHOD_EPOLL;
89} 100}
101
102static void
103epoll_destroy (EV_P)
104{
105 close (epoll_fd);
106
107 ev_free (epoll_events);
108}
109
110static void
111epoll_fork (EV_P)
112{
113 close (epoll_fd);
114
115 while ((epoll_fd = epoll_create (256)) < 0)
116 syserr ("(libev) epoll_create");
117
118 fcntl (epoll_fd, F_SETFD, FD_CLOEXEC);
119
120 fd_rearm_all (EV_A);
121}
122

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