summaryrefslogtreecommitdiffstats
path: root/Utilities/cmlibuv/src/unix/poll.c
blob: 3d5022b22e85b6690f3c0a7d01637bc5826e71ae (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#include "uv.h"
#include "internal.h"

#include <unistd.h>
#include <assert.h>
#include <errno.h>


static void uv__poll_io(uv_loop_t* loop, uv__io_t* w, unsigned int events) {
  uv_poll_t* handle;
  int pevents;

  handle = container_of(w, uv_poll_t, io_watcher);

  /*
   * As documented in the kernel source fs/kernfs/file.c #780
   * poll will return POLLERR|POLLPRI in case of sysfs
   * polling. This does not happen in case of out-of-band
   * TCP messages.
   *
   * The above is the case on (at least) FreeBSD and Linux.
   *
   * So to properly determine a POLLPRI or a POLLERR we need
   * to check for both.
   */
  if ((events & POLLERR) && !(events & UV__POLLPRI)) {
    uv__io_stop(loop, w, POLLIN | POLLOUT | UV__POLLRDHUP | UV__POLLPRI);
    uv__handle_stop(handle);
    handle->poll_cb(handle, UV_EBADF, 0);
    return;
  }

  pevents = 0;
  if (events & POLLIN)
    pevents |= UV_READABLE;
  if (events & UV__POLLPRI)
    pevents |= UV_PRIORITIZED;
  if (events & POLLOUT)
    pevents |= UV_WRITABLE;
  if (events & UV__POLLRDHUP)
    pevents |= UV_DISCONNECT;

  handle->poll_cb(handle, 0, pevents);
}


int uv_poll_init(uv_loop_t* loop, uv_poll_t* handle, int fd) {
  int err;

  if (uv__fd_exists(loop, fd))
    return UV_EEXIST;

  err = uv__io_check_fd(loop, fd);
  if (err)
    return err;

  /* If ioctl(FIONBIO) reports ENOTTY, try fcntl(F_GETFL) + fcntl(F_SETFL).
   * Workaround for e.g. kqueue fds not supporting ioctls.
   */
  err = uv__nonblock(fd, 1);
  if (err == UV_ENOTTY)
    if (uv__nonblock == uv__nonblock_ioctl)
      err = uv__nonblock_fcntl(fd, 1);

  if (err)
    return err;

  uv__handle_init(loop, (uv_handle_t*) handle, UV_POLL);
  uv__io_init(&handle->io_watcher, uv__poll_io, fd);
  handle->poll_cb = NULL;
  return 0;
}


int uv_poll_init_socket(uv_loop_t* loop, uv_poll_t* handle,
    uv_os_sock_t socket) {
  return uv_poll_init(loop, handle, socket);
}


static void uv__poll_stop(uv_poll_t* handle) {
  uv__io_stop(handle->loop,
              &handle->io_watcher,
              POLLIN | POLLOUT | UV__POLLRDHUP | UV__POLLPRI);
  uv__handle_stop(handle);
  uv__platform_invalidate_fd(handle->loop, handle->io_watcher.fd);
}


int uv_poll_stop(uv_poll_t* handle) {
  assert(!uv__is_closing(handle));
  uv__poll_stop(handle);
  return 0;
}


int uv_poll_start(uv_poll_t* handle, int pevents, uv_poll_cb poll_cb) {
  int events;

  assert((pevents & ~(UV_READABLE | UV_WRITABLE | UV_DISCONNECT |
                      UV_PRIORITIZED)) == 0);
  assert(!uv__is_closing(handle));

  uv__poll_stop(handle);

  if (pevents == 0)
    return 0;

  events = 0;
  if (pevents & UV_READABLE)
    events |= POLLIN;
  if (pevents & UV_PRIORITIZED)
    events |= UV__POLLPRI;
  if (pevents & UV_WRITABLE)
    events |= POLLOUT;
  if (pevents & UV_DISCONNECT)
    events |= UV__POLLRDHUP;

  uv__io_start(handle->loop, &handle->io_watcher, events);
  uv__handle_start(handle);
  handle->poll_cb = poll_cb;

  return 0;
}


void uv__poll_close(uv_poll_t* handle) {
  uv__poll_stop(handle);
}