aboutsummaryrefslogtreecommitdiff
path: root/backend/multi/backend.c
blob: 50851109b268949bec82c670e4ce9d6d0884cfc8 (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
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
#define _POSIX_C_SOURCE 200112L
#include <assert.h>
#include <stdbool.h>
#include <stdlib.h>
#include <time.h>
#include <wlr/backend/interface.h>
#include <wlr/backend/session.h>
#include <wlr/util/log.h>
#include "backend/multi.h"
#include "util/signal.h"

struct subbackend_state {
	struct wlr_backend *backend;
	struct wlr_backend *container;
	struct wl_listener new_input;
	struct wl_listener new_output;
	struct wl_listener destroy;
	struct wl_list link;
};

static struct wlr_multi_backend *multi_backend_from_backend(
		struct wlr_backend *wlr_backend) {
	assert(wlr_backend_is_multi(wlr_backend));
	return (struct wlr_multi_backend *)wlr_backend;
}

static bool multi_backend_start(struct wlr_backend *wlr_backend) {
	struct wlr_multi_backend *backend = multi_backend_from_backend(wlr_backend);
	struct subbackend_state *sub;
	wl_list_for_each(sub, &backend->backends, link) {
		if (!wlr_backend_start(sub->backend)) {
			wlr_log(WLR_ERROR, "Failed to initialize backend.");
			return false;
		}
	}
	return true;
}

static void subbackend_state_destroy(struct subbackend_state *sub) {
	wl_list_remove(&sub->new_input.link);
	wl_list_remove(&sub->new_output.link);
	wl_list_remove(&sub->destroy.link);
	wl_list_remove(&sub->link);
	free(sub);
}

static void multi_backend_destroy(struct wlr_backend *wlr_backend) {
	struct wlr_multi_backend *backend = multi_backend_from_backend(wlr_backend);

	wl_list_remove(&backend->display_destroy.link);

	struct subbackend_state *sub, *next;
	wl_list_for_each_safe(sub, next, &backend->backends, link) {
		wlr_backend_destroy(sub->backend);
	}

	// Destroy this backend only after removing all sub-backends
	wlr_signal_emit_safe(&wlr_backend->events.destroy, backend);
	free(backend);
}

static struct wlr_renderer *multi_backend_get_renderer(
		struct wlr_backend *backend) {
	struct wlr_multi_backend *multi = multi_backend_from_backend(backend);

	struct subbackend_state *sub;
	wl_list_for_each(sub, &multi->backends, link) {
		struct wlr_renderer *rend = wlr_backend_get_renderer(sub->backend);
		if (rend != NULL) {
			return rend;
		}
	}
	return NULL;
}

static struct wlr_session *multi_backend_get_session(
		struct wlr_backend *_backend) {
	struct wlr_multi_backend *backend = multi_backend_from_backend(_backend);
	return backend->session;
}

static clockid_t multi_backend_get_presentation_clock(
		struct wlr_backend *backend) {
	struct wlr_multi_backend *multi = multi_backend_from_backend(backend);

	struct subbackend_state *sub;
	wl_list_for_each(sub, &multi->backends, link) {
		if (sub->backend->impl->get_presentation_clock) {
			return wlr_backend_get_presentation_clock(sub->backend);
		}
	}

	return CLOCK_MONOTONIC;
}

struct wlr_backend_impl backend_impl = {
	.start = multi_backend_start,
	.destroy = multi_backend_destroy,
	.get_renderer = multi_backend_get_renderer,
	.get_session = multi_backend_get_session,
	.get_presentation_clock = multi_backend_get_presentation_clock,
};

static void handle_display_destroy(struct wl_listener *listener, void *data) {
	struct wlr_multi_backend *backend =
		wl_container_of(listener, backend, display_destroy);
	multi_backend_destroy((struct wlr_backend*)backend);
}

struct wlr_backend *wlr_multi_backend_create(struct wl_display *display) {
	struct wlr_multi_backend *backend =
		calloc(1, sizeof(struct wlr_multi_backend));
	if (!backend) {
		wlr_log(WLR_ERROR, "Backend allocation failed");
		return NULL;
	}

	wl_list_init(&backend->backends);
	wlr_backend_init(&backend->backend, &backend_impl);

	wl_signal_init(&backend->events.backend_add);
	wl_signal_init(&backend->events.backend_remove);

	backend->display_destroy.notify = handle_display_destroy;
	wl_display_add_destroy_listener(display, &backend->display_destroy);

	return &backend->backend;
}

bool wlr_backend_is_multi(struct wlr_backend *b) {
	return b->impl == &backend_impl;
}

static void new_input_reemit(struct wl_listener *listener, void *data) {
	struct subbackend_state *state = wl_container_of(listener,
			state, new_input);
	wlr_signal_emit_safe(&state->container->events.new_input, data);
}

static void new_output_reemit(struct wl_listener *listener, void *data) {
	struct subbackend_state *state = wl_container_of(listener,
			state, new_output);
	wlr_signal_emit_safe(&state->container->events.new_output, data);
}

static void handle_subbackend_destroy(struct wl_listener *listener,
		void *data) {
	struct subbackend_state *state = wl_container_of(listener, state, destroy);
	subbackend_state_destroy(state);
}

static struct subbackend_state *multi_backend_get_subbackend(struct wlr_multi_backend *multi,
		struct wlr_backend *backend) {
	struct subbackend_state *sub = NULL;
	wl_list_for_each(sub, &multi->backends, link) {
		if (sub->backend == backend) {
			return sub;
		}
	}
	return NULL;
}

bool wlr_multi_backend_add(struct wlr_backend *_multi,
		struct wlr_backend *backend) {
	struct wlr_multi_backend *multi = multi_backend_from_backend(_multi);

	if (multi_backend_get_subbackend(multi, backend)) {
		// already added
		return true;
	}

	struct wlr_renderer *multi_renderer =
		multi_backend_get_renderer(&multi->backend);
	struct wlr_renderer *backend_renderer = wlr_backend_get_renderer(backend);
	if (multi_renderer != NULL && backend_renderer != NULL && multi_renderer != backend_renderer) {
		wlr_log(WLR_ERROR, "Could not add backend: multiple renderers at the "
			"same time aren't supported");
		return false;
	}

	struct subbackend_state *sub = calloc(1, sizeof(struct subbackend_state));
	if (sub == NULL) {
		wlr_log(WLR_ERROR, "Could not add backend: allocation failed");
		return false;
	}
	wl_list_insert(&multi->backends, &sub->link);

	sub->backend = backend;
	sub->container = &multi->backend;

	wl_signal_add(&backend->events.destroy, &sub->destroy);
	sub->destroy.notify = handle_subbackend_destroy;

	wl_signal_add(&backend->events.new_input, &sub->new_input);
	sub->new_input.notify = new_input_reemit;

	wl_signal_add(&backend->events.new_output, &sub->new_output);
	sub->new_output.notify = new_output_reemit;

	wlr_signal_emit_safe(&multi->events.backend_add, backend);
	return true;
}

void wlr_multi_backend_remove(struct wlr_backend *_multi,
		struct wlr_backend *backend) {
	struct wlr_multi_backend *multi = multi_backend_from_backend(_multi);

	struct subbackend_state *sub =
		multi_backend_get_subbackend(multi, backend);

	if (sub) {
		wlr_signal_emit_safe(&multi->events.backend_remove, backend);
		subbackend_state_destroy(sub);
	}
}

bool wlr_multi_is_empty(struct wlr_backend *_backend) {
	assert(wlr_backend_is_multi(_backend));
	struct wlr_multi_backend *backend = (struct wlr_multi_backend *)_backend;
	return wl_list_length(&backend->backends) < 1;
}

void wlr_multi_for_each_backend(struct wlr_backend *_backend,
		void (*callback)(struct wlr_backend *backend, void *data), void *data) {
	assert(wlr_backend_is_multi(_backend));
	struct wlr_multi_backend *backend = (struct wlr_multi_backend *)_backend;
	struct subbackend_state *sub;
	wl_list_for_each(sub, &backend->backends, link) {
		callback(sub->backend, data);
	}
}