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
uv__poll_io(uv_loop_t * loop,uv__io_t * w,unsigned int events)30 static 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
uv_poll_init(uv_loop_t * loop,uv_poll_t * handle,int fd)68 int 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 UV__NONBLOCK_IS_IOCTL
83 if (err == UV_ENOTTY)
84 err = uv__nonblock_fcntl(fd, 1);
85 #endif
86
87 if (err)
88 return err;
89
90 uv__handle_init(loop, (uv_handle_t*) handle, UV_POLL);
91 uv__io_init(&handle->io_watcher, uv__poll_io, fd);
92 handle->poll_cb = NULL;
93 return 0;
94 }
95
96
uv_poll_init_socket(uv_loop_t * loop,uv_poll_t * handle,uv_os_sock_t socket)97 int uv_poll_init_socket(uv_loop_t* loop, uv_poll_t* handle,
98 uv_os_sock_t socket) {
99 return uv_poll_init(loop, handle, socket);
100 }
101
102
uv__poll_stop(uv_poll_t * handle)103 static void uv__poll_stop(uv_poll_t* handle) {
104 uv__io_stop(handle->loop,
105 &handle->io_watcher,
106 POLLIN | POLLOUT | UV__POLLRDHUP | UV__POLLPRI);
107 uv__handle_stop(handle);
108 uv__platform_invalidate_fd(handle->loop, handle->io_watcher.fd);
109 }
110
111
uv_poll_stop(uv_poll_t * handle)112 int uv_poll_stop(uv_poll_t* handle) {
113 assert(!uv__is_closing(handle));
114 uv__poll_stop(handle);
115 return 0;
116 }
117
118
uv_poll_start(uv_poll_t * handle,int pevents,uv_poll_cb poll_cb)119 int uv_poll_start(uv_poll_t* handle, int pevents, uv_poll_cb poll_cb) {
120 uv__io_t** watchers;
121 uv__io_t* w;
122 int events;
123
124 assert((pevents & ~(UV_READABLE | UV_WRITABLE | UV_DISCONNECT |
125 UV_PRIORITIZED)) == 0);
126 assert(!uv__is_closing(handle));
127
128 watchers = handle->loop->watchers;
129 w = &handle->io_watcher;
130
131 if (uv__fd_exists(handle->loop, w->fd))
132 if (watchers[w->fd] != w)
133 return UV_EEXIST;
134
135 uv__poll_stop(handle);
136
137 if (pevents == 0)
138 return 0;
139
140 events = 0;
141 if (pevents & UV_READABLE)
142 events |= POLLIN;
143 if (pevents & UV_PRIORITIZED)
144 events |= UV__POLLPRI;
145 if (pevents & UV_WRITABLE)
146 events |= POLLOUT;
147 if (pevents & UV_DISCONNECT)
148 events |= UV__POLLRDHUP;
149
150 uv__io_start(handle->loop, &handle->io_watcher, events);
151 uv__handle_start(handle);
152 handle->poll_cb = poll_cb;
153
154 return 0;
155 }
156
157
uv__poll_close(uv_poll_t * handle)158 void uv__poll_close(uv_poll_t* handle) {
159 uv__poll_stop(handle);
160 }
161