summaryrefslogtreecommitdiffstats
path: root/binding/audiomixer-binding.c
blob: 005f5c77cea1b85941ee29425b5c277988aa184b (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
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
/*
 * Copyright © 2019 Collabora Ltd.
 *   @author George Kiagiadakis <george.kiagiadakis@collabora.com>
 *
 * SPDX-License-Identifier: MIT
 */

#include <string.h>
#include <json-c/json.h>
#include <afb/afb-binding.h>
#include <systemd/sd-event.h>
#include "audiomixer.h"

static struct audiomixer *audiomixer;
static afb_event_t controls_changed;
static afb_event_t volume_changed;
static afb_event_t mute_changed;
static sd_event_source *controls_changed_source;

static int
audiomixer_controls_changed_deferred(sd_event_source *s, void *data)
{
	afb_event_push(controls_changed, NULL);

	sd_event_source_unref(controls_changed_source);
	controls_changed_source = NULL;
	return 0;
}

struct value_changed_data
{
	unsigned int change_mask;
	struct mixer_control control;
	sd_event_source *source;
};

static int
audiomixer_value_changed_deferred(sd_event_source *s, void *data)
{
	struct value_changed_data *d = data;
	json_object *json;

	json = json_object_new_object();
	json_object_object_add(json, "control",
		json_object_new_string(d->control.name));

	if (d->change_mask & MIXER_CONTROL_CHANGE_FLAG_VOLUME) {
		json_object_object_add(json, "value",
			json_object_new_double(d->control.volume));
		afb_event_push(volume_changed, json);
	} else if (d->change_mask & MIXER_CONTROL_CHANGE_FLAG_MUTE) {
		json_object_object_add(json, "value",
			json_object_new_int(d->control.mute));
		afb_event_push(mute_changed, json);
	}

	sd_event_source_unref(d->source);
	free(d);
	return 0;
}

/* called in audiomixer's thread */
static void
audiomixer_controls_changed(void *data)
{
	sd_event *e = afb_daemon_get_event_loop();
	sd_event_add_defer(e, &controls_changed_source,
		audiomixer_controls_changed_deferred, NULL);
}


/* called in audiomixer's thread */
static void
audiomixer_value_changed(void *data,
	unsigned int change_mask,
	const struct mixer_control *control)
{
	sd_event *e = afb_daemon_get_event_loop();
	struct value_changed_data *d = calloc(1, sizeof(*d));

	d->change_mask = change_mask;
	d->control = *control;

	if (sd_event_add_defer(e, &d->source,
			audiomixer_value_changed_deferred, d) < 0)
		free(d);
}

static const struct audiomixer_events audiomixer_events = {
	.controls_changed = audiomixer_controls_changed,
	.value_changed = audiomixer_value_changed,
};

static int
cleanup(sd_event_source *s, void *data)
{
	audiomixer_free(audiomixer);
	audiomixer = NULL;
	return 0;
}

static int
init(afb_api_t api)
{
	sd_event *e = afb_daemon_get_event_loop();

	controls_changed = afb_api_make_event(api, "controls_changed");
	volume_changed = afb_api_make_event(api, "volume_changed");
	mute_changed = afb_api_make_event(api, "mute_changed");

	audiomixer = audiomixer_new();
	sd_event_add_exit(e, NULL, cleanup, NULL);

	audiomixer_add_event_listener(audiomixer, &audiomixer_events, NULL);

	return 0;
}

static void
list_controls_cb(afb_req_t request)
{
	json_object *ret_json, *nest_json;
	const struct mixer_control **ctls;
	unsigned int n_controls, i;

	audiomixer_lock(audiomixer);

	if (audiomixer_ensure_connected(audiomixer, 3) < 0) {
		afb_req_fail(request, "failed",
			"Could not connect to the PipeWire daemon");
		goto unlock;
	}

	if (audiomixer_ensure_controls(audiomixer, 3) < 0) {
		AFB_REQ_NOTICE(request, "No mixer controls were exposed "
			"in PipeWire after 3 seconds");
	}

	ctls = audiomixer_get_active_controls(audiomixer, &n_controls);

	ret_json = json_object_new_array();
	for (i = 0; i < n_controls; i++) {
		nest_json = json_object_new_object();
		json_object_object_add(nest_json, "control",
				json_object_new_string(ctls[i]->name));
		json_object_object_add(nest_json, "volume",
				json_object_new_double(ctls[i]->volume));
		json_object_object_add(nest_json, "mute",
				json_object_new_int(ctls[i]->mute));
		json_object_array_add(ret_json, nest_json);
	}
	afb_req_success(request, ret_json, NULL);

unlock:
	audiomixer_unlock(audiomixer);
}

static void
volume_cb(afb_req_t request)
{
	json_object *ret_json;
	const char *control = afb_req_value(request, "control");
	const char *value = afb_req_value(request, "value");
	const struct mixer_control *ctl;
	double volume;

	audiomixer_lock(audiomixer);

	if (!control) {
		afb_req_fail(request, "failed",
			"Invalid arguments: missing 'control'");
		goto unlock;
	}

	if (audiomixer_ensure_connected(audiomixer, 3) < 0) {
		afb_req_fail(request, "failed",
			"Could not connect to the PipeWire daemon");
		goto unlock;
	}

	if (audiomixer_ensure_controls(audiomixer, 3) < 0) {
		AFB_REQ_NOTICE(request, "No mixer controls were exposed "
			"in PipeWire after 3 seconds");
	}

	ctl = audiomixer_find_control(audiomixer, control);
	if (!ctl) {
		afb_req_fail(request, "failed", "Could not find control");
		goto unlock;
	}

	if(value) {
		char *endptr;
		volume = strtod(value, &endptr);
		if (endptr == value || volume < -0.00001 || volume > 1.00001) {
			afb_req_fail(request, "failed",
				"Invalid volume value (must be between 0.0 and 1.0)");
			goto unlock;
		}

		audiomixer_change_volume(audiomixer, ctl, volume);
	} else {
		volume = ctl->volume;
	}

	ret_json = json_object_new_object();
	json_object_object_add(ret_json, "volume", json_object_new_double(volume));
	afb_req_success(request, ret_json, NULL);

unlock:
	audiomixer_unlock(audiomixer);
}

static void
mute_cb(afb_req_t request)
{
	json_object *ret_json;
	const char *control = afb_req_value(request, "control");
	const char *value = afb_req_value(request, "value");
	const struct mixer_control *ctl;
	int mute;

	audiomixer_lock(audiomixer);

	if (!control) {
		afb_req_fail(request, "failed",
			"Invalid arguments: missing 'control'");
		goto unlock;
	}

	if (audiomixer_ensure_connected(audiomixer, 3) < 0) {
		afb_req_fail(request, "failed",
			"Could not connect to the PipeWire daemon");
		goto unlock;
	}

	if (audiomixer_ensure_controls(audiomixer, 3) < 0) {
		AFB_REQ_NOTICE(request, "No mixer controls were exposed "
			"in PipeWire after 3 seconds");
	}

	ctl = audiomixer_find_control(audiomixer, control);
	if (!ctl) {
		afb_req_fail(request, "failed", "Could not find control");
		goto unlock;
	}

	if(value) {
		char *endptr;
		mute = (int) strtol(value, &endptr, 10);
		if (endptr == value || mute < 0 || mute > 1) {
			afb_req_fail(request, "failed",
				"Invalid mute value (must be integer 0 or 1)");
			goto unlock;
		}

		audiomixer_change_mute(audiomixer, ctl, mute);
	} else {
		mute = ctl->mute;
	}

	ret_json = json_object_new_object();
	json_object_object_add(ret_json, "mute", json_object_new_int(mute));
	afb_req_success(request, ret_json, NULL);

unlock:
	audiomixer_unlock(audiomixer);
}

static void
subscribe_cb(afb_req_t request)
{
	const char *eventstr = afb_req_value(request, "event");
	afb_event_t event;

	if (!eventstr) {
		afb_req_fail(request, "failed",
			"Invalid arguments: missing 'event'");
		return;
	}

	if (!strcmp(eventstr, "controls_changed"))
		event = controls_changed;
	else if (!strcmp(eventstr, "volume_changed"))
		event = volume_changed;
	else if (!strcmp(eventstr, "mute_changed"))
		event = mute_changed;
	else {
		afb_req_fail(request, "failed", "Invalid event name");
		return;
	}

	if (afb_req_subscribe(request, event) != 0)
		afb_req_fail(request, "failed", "Failed to subscribe to event");
	else
		afb_req_success(request, NULL, "Subscribed");
}

static void
unsubscribe_cb(afb_req_t request)
{
	const char *eventstr = afb_req_value(request, "event");
	afb_event_t event;

	if (!eventstr) {
		afb_req_fail(request, "failed",
			"Invalid arguments: missing 'event'");
		return;
	}

	if (!strcmp(eventstr, "controls_changed"))
		event = controls_changed;
	else if (!strcmp(eventstr, "volume_changed"))
		event = volume_changed;
	else if (!strcmp(eventstr, "mute_changed"))
		event = mute_changed;
	else {
		afb_req_fail(request, "failed", "Invalid event name");
		return;
	}

	if (afb_req_unsubscribe(request, event) != 0)
		afb_req_fail(request, "failed", "Failed to unsubscribe from event");
	else
		afb_req_success(request, NULL, "Unsubscribed");
}

static const afb_verb_t verbs[]= {
	{ .verb = "list_controls", .callback = list_controls_cb, .info = "List the available controls" },
	{ .verb = "volume",        .callback = volume_cb,        .info = "Get/Set volume" },
	{ .verb = "mute",          .callback = mute_cb,          .info = "Get/Set mute" },
	{ .verb = "subscribe",     .callback = subscribe_cb,     .info = "Subscribe to mixer events" },
	{ .verb = "unsubscribe",   .callback = unsubscribe_cb,   .info = "Unsubscribe from mixer events" },
	{ }
};

const afb_binding_t afbBindingV3 = {
	.api  = "audiomixer",
	.specification = "AudioMixer API",
	.verbs = verbs,
	.init = init,
};