summaryrefslogtreecommitdiff
path: root/thirdparty/libwebsockets/lib/plat/unix/unix-service.c
blob: e61ef59959cb25ff0e8ce2b4fcaa7d48abe74f86 (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
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
/*
 * libwebsockets - small server side websockets and web server implementation
 *
 * Copyright (C) 2010-2018 Andy Green <andy@warmcat.com>
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation:
 *  version 2.1 of the License.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 *  MA  02110-1301  USA
 */

#define _GNU_SOURCE
#include "core/private.h"

int
lws_poll_listen_fd(struct lws_pollfd *fd)
{
	return poll(fd, 1, 0);
}

LWS_EXTERN int
_lws_plat_service_tsi(struct lws_context *context, int timeout_ms, int tsi)
{
	volatile struct lws_foreign_thread_pollfd *ftp, *next;
	volatile struct lws_context_per_thread *vpt;
	struct lws_context_per_thread *pt;
	int n = -1, m, c;

	/* stay dead once we are dead */

	if (!context || !context->vhost_list)
		return 1;

	pt = &context->pt[tsi];
	vpt = (volatile struct lws_context_per_thread *)pt;

	lws_stats_atomic_bump(context, pt, LWSSTATS_C_SERVICE_ENTRY, 1);

	if (timeout_ms < 0)
		goto faked_service;

	if (context->event_loop_ops->run_pt)
		context->event_loop_ops->run_pt(context, tsi);

	if (!pt->service_tid_detected) {
		struct lws _lws;

		memset(&_lws, 0, sizeof(_lws));
		_lws.context = context;

		pt->service_tid  =
			context->vhost_list->protocols[0].callback(
			&_lws, LWS_CALLBACK_GET_THREAD_ID, NULL, NULL, 0);
		pt->service_tid_detected = 1;
	}

	/*
	 * is there anybody with pending stuff that needs service forcing?
	 */
	if (!lws_service_adjust_timeout(context, 1, tsi)) {
		/* -1 timeout means just do forced service */
		_lws_plat_service_tsi(context, -1, pt->tid);
		/* still somebody left who wants forced service? */
		if (!lws_service_adjust_timeout(context, 1, pt->tid))
			/* yes... come back again quickly */
			timeout_ms = 0;
	}

	if (timeout_ms) {
		lws_pt_lock(pt, __func__);
		/* don't stay in poll wait longer than next hr timeout */
		lws_usec_t t =  __lws_hrtimer_service(pt);
		if ((lws_usec_t)timeout_ms * 1000 > t)
			timeout_ms = t / 1000;
		lws_pt_unlock(pt);
	}

	vpt->inside_poll = 1;
	lws_memory_barrier();
	n = poll(pt->fds, pt->fds_count, timeout_ms);
	vpt->inside_poll = 0;
	lws_memory_barrier();

	/* Collision will be rare and brief.  Just spin until it completes */
	while (vpt->foreign_spinlock)
		;

	/*
	 * At this point we are not inside a foreign thread pollfd change,
	 * and we have marked ourselves as outside the poll() wait.  So we
	 * are the only guys that can modify the lws_foreign_thread_pollfd
	 * list on the pt.  Drain the list and apply the changes to the
	 * affected pollfds in the correct order.
	 */

	lws_pt_lock(pt, __func__);

	ftp = vpt->foreign_pfd_list;
	//lwsl_notice("cleared list %p\n", ftp);
	while (ftp) {
		struct lws *wsi;
		struct lws_pollfd *pfd;

		next = ftp->next;
		pfd = &vpt->fds[ftp->fd_index];
		if (lws_socket_is_valid(pfd->fd)) {
			wsi = wsi_from_fd(context, pfd->fd);
			if (wsi)
				__lws_change_pollfd(wsi, ftp->_and, ftp->_or);
		}
		lws_free((void *)ftp);
		ftp = next;
	}
	vpt->foreign_pfd_list = NULL;
	lws_memory_barrier();

	/* we have come out of a poll wait... check the hrtimer list */

	__lws_hrtimer_service(pt);

	lws_pt_unlock(pt);

	m = 0;
#if defined(LWS_ROLE_WS) && !defined(LWS_WITHOUT_EXTENSIONS)
	m |= !!pt->ws.rx_draining_ext_list;
#endif

	if (pt->context->tls_ops &&
	    pt->context->tls_ops->fake_POLLIN_for_buffered)
		m |= pt->context->tls_ops->fake_POLLIN_for_buffered(pt);

	if (!m && !n) { /* nothing to do */
		lws_service_fd_tsi(context, NULL, tsi);
		lws_service_do_ripe_rxflow(pt);

		return 0;
	}

faked_service:
	m = lws_service_flag_pending(context, tsi);
	if (m)
		c = -1; /* unknown limit */
	else
		if (n < 0) {
			if (LWS_ERRNO != LWS_EINTR)
				return -1;
			return 0;
		} else
			c = n;

	/* any socket with events to service? */
	for (n = 0; n < (int)pt->fds_count && c; n++) {
		if (!pt->fds[n].revents)
			continue;

		c--;

		m = lws_service_fd_tsi(context, &pt->fds[n], tsi);
		if (m < 0) {
			lwsl_err("%s: lws_service_fd_tsi returned %d\n",
				 __func__, m);
			return -1;
		}
		/* if something closed, retry this slot */
		if (m)
			n--;
	}

	lws_service_do_ripe_rxflow(pt);

	return 0;
}

int
lws_plat_check_connection_error(struct lws *wsi)
{
	return 0;
}

int
lws_plat_service(struct lws_context *context, int timeout_ms)
{
	return _lws_plat_service_tsi(context, timeout_ms, 0);
}


void
lws_plat_service_periodic(struct lws_context *context)
{
	/* if our parent went down, don't linger around */
	if (context->started_with_parent &&
	    kill(context->started_with_parent, 0) < 0)
		kill(getpid(), SIGTERM);
}