1/*
2 * libwebsockets - small server side websockets and web server implementation
3 *
4 * Copyright (C) 2010 - 2020 Andy Green <andy@warmcat.com>
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to
8 * deal in the Software without restriction, including without limitation the
9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22 * IN THE SOFTWARE.
23 */
24
25#include "private-lib-core.h"
26
27void
28lws_state_reg_notifier(lws_state_manager_t *mgr,
29		       lws_state_notify_link_t *notify_link)
30{
31	lws_dll2_add_head(&notify_link->list, &mgr->notify_list);
32}
33
34void
35lws_state_reg_deregister(lws_state_notify_link_t *nl)
36{
37	lws_dll2_remove(&nl->list);
38}
39
40void
41lws_state_reg_notifier_list(lws_state_manager_t *mgr,
42			    lws_state_notify_link_t * const *notify_link_array)
43{
44	if (notify_link_array)
45		while (*notify_link_array)
46			lws_state_reg_notifier(mgr, *notify_link_array++);
47}
48
49#if (_LWS_ENABLED_LOGS & (LLL_INFO | LLL_DEBUG))
50static const char *
51_systnm(lws_state_manager_t *mgr, int state, char *temp8)
52{
53	if (!mgr->state_names) {
54		lws_snprintf(temp8, 8, "%d", state);
55		return temp8;
56	}
57
58	return mgr->state_names[state];
59}
60#endif
61
62static int
63_report(lws_state_manager_t *mgr, int a, int b)
64{
65#if (_LWS_ENABLED_LOGS & LLL_INFO)
66	char temp8[8];
67#endif
68
69	lws_start_foreach_dll(struct lws_dll2 *, d, mgr->notify_list.head) {
70		lws_state_notify_link_t *l =
71			lws_container_of(d, lws_state_notify_link_t, list);
72
73		if (l->notify_cb(mgr, l, a, b)) {
74			/* a dependency took responsibility for retry */
75
76#if (_LWS_ENABLED_LOGS & LLL_INFO)
77			lwsl_cx_info(mgr->context, "%s: %s: rejected '%s' -> '%s'",
78				     mgr->name, l->name,
79				     _systnm(mgr, a, temp8),
80				     _systnm(mgr, b, temp8));
81#endif
82
83			return 1;
84		}
85
86	} lws_end_foreach_dll(d);
87
88	return 0;
89}
90
91static int
92_lws_state_transition(lws_state_manager_t *mgr, int target)
93{
94#if (_LWS_ENABLED_LOGS & LLL_DEBUG)
95	char temp8[8];
96#endif
97
98	if (_report(mgr, mgr->state, target))
99		return 1;
100
101#if (_LWS_ENABLED_LOGS & LLL_DEBUG)
102	if (mgr->context)
103	lwsl_cx_debug(mgr->context, "%s: changed %d '%s' -> %d '%s'", mgr->name,
104		   mgr->state, _systnm(mgr, mgr->state, temp8), target,
105		   _systnm(mgr, target, temp8));
106#endif
107
108	mgr->state = target;
109
110	/* Indicate success by calling the notifers again with both args same */
111	_report(mgr, target, target);
112
113#if defined(LWS_WITH_SYS_SMD)
114	if (mgr->smd_class && mgr->context)
115		(void)lws_smd_msg_printf(mgr->context,
116				   mgr->smd_class, "{\"state\":\"%s\"}",
117				   mgr->state_names[target]);
118#endif
119
120	return 0;
121}
122
123int
124lws_state_transition_steps(lws_state_manager_t *mgr, int target)
125{
126	int n = 0;
127#if (_LWS_ENABLED_LOGS & LLL_INFO)
128	int i = mgr->state;
129	char temp8[8];
130#endif
131
132	if (mgr->state > target)
133		return 0;
134
135	while (!n && mgr->state != target)
136		n = _lws_state_transition(mgr, mgr->state + 1);
137
138#if (_LWS_ENABLED_LOGS & LLL_INFO)
139	lwsl_cx_info(mgr->context, "%s -> %s", _systnm(mgr, i, temp8),
140			_systnm(mgr, mgr->state, temp8));
141#endif
142
143	return 0;
144}
145
146int
147lws_state_transition(lws_state_manager_t *mgr, int target)
148{
149	if (mgr->state != target)
150		_lws_state_transition(mgr, target);
151
152	return 0;
153}
154