1/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
2 *
3 * Permission is hereby granted, free of charge, to any person obtaining a copy
4 * of this software and associated documentation files (the "Software"), to
5 * deal in the Software without restriction, including without limitation the
6 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
7 * sell copies of the Software, and to permit persons to whom the Software is
8 * furnished to do so, subject to the following conditions:
9 *
10 * The above copyright notice and this permission notice shall be included in
11 * all copies or substantial portions of the Software.
12 *
13 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
17 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
18 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
19 * IN THE SOFTWARE.
20 */
21
22#include "uv.h"
23#include "internal.h"
24
25#include <unistd.h>
26#include <assert.h>
27#include <errno.h>
28
29
30static void uv__poll_io(uv_loop_t* loop, uv__io_t* w, unsigned int events) {
31 uv_poll_t* handle;
32 int pevents;
33
34 handle = container_of(w, uv_poll_t, io_watcher);
35
36 /*
37 * As documented in the kernel source fs/kernfs/file.c #780
38 * poll will return POLLERR|POLLPRI in case of sysfs
39 * polling. This does not happen in case of out-of-band
40 * TCP messages.
41 *
42 * The above is the case on (at least) FreeBSD and Linux.
43 *
44 * So to properly determine a POLLPRI or a POLLERR we need
45 * to check for both.
46 */
47 if ((events & POLLERR) && !(events & UV__POLLPRI)) {
48 uv__io_stop(loop, w, POLLIN | POLLOUT | UV__POLLRDHUP | UV__POLLPRI);
49 uv__handle_stop(handle);
50 handle->poll_cb(handle, UV_EBADF, 0);
51 return;
52 }
53
54 pevents = 0;
55 if (events & POLLIN)
56 pevents |= UV_READABLE;
57 if (events & UV__POLLPRI)
58 pevents |= UV_PRIORITIZED;
59 if (events & POLLOUT)
60 pevents |= UV_WRITABLE;
61 if (events & UV__POLLRDHUP)
62 pevents |= UV_DISCONNECT;
63
64 handle->poll_cb(handle, 0, pevents);
65}
66
67
68int uv_poll_init(uv_loop_t* loop, uv_poll_t* handle, int fd) {
69 int err;
70
71 if (uv__fd_exists(loop, fd))
72 return UV_EEXIST;
73
74 err = uv__io_check_fd(loop, fd);
75 if (err)
76 return err;
77
78 /* If ioctl(FIONBIO) reports ENOTTY, try fcntl(F_GETFL) + fcntl(F_SETFL).
79 * Workaround for e.g. kqueue fds not supporting ioctls.
80 */
81 err = uv__nonblock(fd, 1);
82 if (err == UV_ENOTTY)
83 if (uv__nonblock == uv__nonblock_ioctl)
84 err = uv__nonblock_fcntl(fd, 1);
85
86 if (err)
87 return err;
88
89 uv__handle_init(loop, (uv_handle_t*) handle, UV_POLL);
90 uv__io_init(&handle->io_watcher, uv__poll_io, fd);
91 handle->poll_cb = NULL;
92 return 0;
93}
94
95
96int uv_poll_init_socket(uv_loop_t* loop, uv_poll_t* handle,
97 uv_os_sock_t socket) {
98 return uv_poll_init(loop, handle, socket);
99}
100
101
102static void uv__poll_stop(uv_poll_t* handle) {
103 uv__io_stop(handle->loop,
104 &handle->io_watcher,
105 POLLIN | POLLOUT | UV__POLLRDHUP | UV__POLLPRI);
106 uv__handle_stop(handle);
107 uv__platform_invalidate_fd(handle->loop, handle->io_watcher.fd);
108}
109
110
111int uv_poll_stop(uv_poll_t* handle) {
112 assert(!uv__is_closing(handle));
113 uv__poll_stop(handle);
114 return 0;
115}
116
117
118int uv_poll_start(uv_poll_t* handle, int pevents, uv_poll_cb poll_cb) {
119 uv__io_t** watchers;
120 uv__io_t* w;
121 int events;
122
123 assert((pevents & ~(UV_READABLE | UV_WRITABLE | UV_DISCONNECT |
124 UV_PRIORITIZED)) == 0);
125 assert(!uv__is_closing(handle));
126
127 watchers = handle->loop->watchers;
128 w = &handle->io_watcher;
129
130 if (uv__fd_exists(handle->loop, w->fd))
131 if (watchers[w->fd] != w)
132 return UV_EEXIST;
133
134 uv__poll_stop(handle);
135
136 if (pevents == 0)
137 return 0;
138
139 events = 0;
140 if (pevents & UV_READABLE)
141 events |= POLLIN;
142 if (pevents & UV_PRIORITIZED)
143 events |= UV__POLLPRI;
144 if (pevents & UV_WRITABLE)
145 events |= POLLOUT;
146 if (pevents & UV_DISCONNECT)
147 events |= UV__POLLRDHUP;
148
149 uv__io_start(handle->loop, &handle->io_watcher, events);
150 uv__handle_start(handle);
151 handle->poll_cb = poll_cb;
152
153 return 0;
154}
155
156
157void uv__poll_close(uv_poll_t* handle) {
158 uv__poll_stop(handle);
159}
160