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/cvs/libev/ev_poll.c
Revision: 1.17
Committed: Wed Nov 28 11:15:55 2007 UTC (16 years, 11 months ago) by root
Content type: text/plain
Branch: MAIN
CVS Tags: rel-1_71, rel-1_72, rel-1_5, rel-1_6
Changes since 1.16: +3 -3 lines
Log Message:
experimental, and likely broken, inotify support

File Contents

# 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     * 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 1.9 array_needsize (int, 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 root 1.10 pollidxs [fd] = idx = pollcnt++;
56 root 1.14 array_needsize (struct pollfd, polls, pollmax, pollcnt, EMPTY2);
57 root 1.2 polls [idx].fd = fd;
58     }
59 root 1.1
60 root 1.10 assert (polls [idx].fd == fd);
61    
62 root 1.2 if (nev)
63     polls [idx].events =
64     (nev & EV_READ ? POLLIN : 0)
65     | (nev & EV_WRITE ? POLLOUT : 0);
66     else /* remove pollfd */
67     {
68 root 1.10 pollidxs [fd] = -1;
69    
70     if (idx < --pollcnt)
71 root 1.2 {
72     polls [idx] = polls [pollcnt];
73     pollidxs [polls [idx].fd] = idx;
74     }
75     }
76 root 1.1 }
77    
78     static void
79 root 1.3 poll_poll (EV_P_ ev_tstamp timeout)
80 root 1.1 {
81 root 1.7 int i;
82 root 1.11 int res = poll (polls, pollcnt, (int)ceil (timeout * 1000.));
83 root 1.1
84 root 1.7 if (res < 0)
85 root 1.1 {
86 root 1.2 if (errno == EBADF)
87 root 1.3 fd_ebadf (EV_A);
88 root 1.7 else if (errno == ENOMEM && !syserr_cb)
89 root 1.3 fd_enomem (EV_A);
90 root 1.7 else if (errno != EINTR)
91 root 1.8 syserr ("(libev) poll");
92 root 1.7
93     return;
94 root 1.1 }
95 root 1.7
96     for (i = 0; i < pollcnt; ++i)
97 root 1.12 if (polls [i].revents & POLLNVAL)
98     fd_kill (EV_A_ polls [i].fd);
99     else
100     fd_event (
101     EV_A_
102     polls [i].fd,
103     (polls [i].revents & (POLLOUT | POLLERR | POLLHUP) ? EV_WRITE : 0)
104     | (polls [i].revents & (POLLIN | POLLERR | POLLHUP) ? EV_READ : 0)
105     );
106 root 1.1 }
107    
108 root 1.17 int inline_size
109 root 1.3 poll_init (EV_P_ int flags)
110 root 1.1 {
111 root 1.16 backend_fudge = 1e-3; /* needed to compensate for select returning early, very conservative */
112     backend_modify = poll_modify;
113     backend_poll = poll_poll;
114 root 1.3
115 root 1.4 pollidxs = 0; pollidxmax = 0;
116 root 1.5 polls = 0; pollmax = 0; pollcnt = 0;
117 root 1.4
118 root 1.15 return EVBACKEND_POLL;
119 root 1.1 }
120 root 1.4
121 root 1.17 void inline_size
122 root 1.4 poll_destroy (EV_P)
123     {
124 root 1.7 ev_free (pollidxs);
125     ev_free (polls);
126 root 1.4 }
127 root 1.9