1 /*
2  *  A simple PCM loopback utility
3  *  Copyright (c) 2010 by Jaroslav Kysela <perex@perex.cz>
4  *
5  *     Author: Jaroslav Kysela <perex@perex.cz>
6  *
7  *
8  *   This program is free software; you can redistribute it and/or modify
9  *   it under the terms of the GNU General Public License as published by
10  *   the Free Software Foundation; either version 2 of the License, or
11  *   (at your option) any later version.
12  *
13  *   This program is distributed in the hope that it will be useful,
14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  *   GNU General Public License for more details.
17  *
18  *   You should have received a copy of the GNU General Public License
19  *   along with this program; if not, write to the Free Software
20  *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
21  *
22  */
23 
24 #include <ctype.h>
25 #include <syslog.h>
26 #include <alsa/asoundlib.h>
27 #include "alsaloop.h"
28 
id_str(snd_ctl_elem_id_t * id)29 static char *id_str(snd_ctl_elem_id_t *id)
30 {
31 	static char str[128];
32 
33 	sprintf(str, "%i,%s,%i,%i,%s,%i",
34 		snd_ctl_elem_id_get_numid(id),
35 		snd_ctl_elem_iface_name(snd_ctl_elem_id_get_interface(id)),
36 		snd_ctl_elem_id_get_device(id),
37 		snd_ctl_elem_id_get_subdevice(id),
38 		snd_ctl_elem_id_get_name(id),
39 		snd_ctl_elem_id_get_index(id));
40 	return str;
41 }
42 
control_parse_id(const char * str,snd_ctl_elem_id_t * id)43 int control_parse_id(const char *str, snd_ctl_elem_id_t *id)
44 {
45 	int c, size, numid;
46 	char *ptr;
47 
48 	while (*str == ' ' || *str == '\t')
49 		str++;
50 	if (!(*str))
51 		return -EINVAL;
52 	snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_MIXER);	/* default */
53 	while (*str) {
54 		if (!strncasecmp(str, "numid=", 6)) {
55 			str += 6;
56 			numid = atoi(str);
57 			if (numid <= 0) {
58 				logit(LOG_CRIT, "Invalid numid %d\n", numid);
59 				return -EINVAL;
60 			}
61 			snd_ctl_elem_id_set_numid(id, atoi(str));
62 			while (isdigit(*str))
63 				str++;
64 		} else if (!strncasecmp(str, "iface=", 6)) {
65 			str += 6;
66 			if (!strncasecmp(str, "card", 4)) {
67 				snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_CARD);
68 				str += 4;
69 			} else if (!strncasecmp(str, "mixer", 5)) {
70 				snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_MIXER);
71 				str += 5;
72 			} else if (!strncasecmp(str, "pcm", 3)) {
73 				snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_PCM);
74 				str += 3;
75 			} else if (!strncasecmp(str, "rawmidi", 7)) {
76 				snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_RAWMIDI);
77 				str += 7;
78 			} else if (!strncasecmp(str, "timer", 5)) {
79 				snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_TIMER);
80 				str += 5;
81 			} else if (!strncasecmp(str, "sequencer", 9)) {
82 				snd_ctl_elem_id_set_interface(id, SND_CTL_ELEM_IFACE_SEQUENCER);
83 				str += 9;
84 			} else {
85 				return -EINVAL;
86 			}
87 		} else if (!strncasecmp(str, "name=", 5)) {
88 			char buf[64];
89 			str += 5;
90 			ptr = buf;
91 			size = 0;
92 			if (*str == '\'' || *str == '\"') {
93 				c = *str++;
94 				while (*str && *str != c) {
95 					if (size < (int)sizeof(buf)) {
96 						*ptr++ = *str;
97 						size++;
98 					}
99 					str++;
100 				}
101 				if (*str == c)
102 					str++;
103 			} else {
104 				while (*str && *str != ',') {
105 					if (size < (int)sizeof(buf)) {
106 						*ptr++ = *str;
107 						size++;
108 					}
109 					str++;
110 				}
111 			}
112 			*ptr = '\0';
113 			snd_ctl_elem_id_set_name(id, buf);
114 		} else if (!strncasecmp(str, "index=", 6)) {
115 			str += 6;
116 			snd_ctl_elem_id_set_index(id, atoi(str));
117 			while (isdigit(*str))
118 				str++;
119 		} else if (!strncasecmp(str, "device=", 7)) {
120 			str += 7;
121 			snd_ctl_elem_id_set_device(id, atoi(str));
122 			while (isdigit(*str))
123 				str++;
124 		} else if (!strncasecmp(str, "subdevice=", 10)) {
125 			str += 10;
126 			snd_ctl_elem_id_set_subdevice(id, atoi(str));
127 			while (isdigit(*str))
128 				str++;
129 		}
130 		if (*str == ',') {
131 			str++;
132 		} else {
133 			if (*str)
134 				return -EINVAL;
135 		}
136 	}
137 	return 0;
138 }
139 
control_id_match(snd_ctl_elem_id_t * id1,snd_ctl_elem_id_t * id2)140 int control_id_match(snd_ctl_elem_id_t *id1, snd_ctl_elem_id_t *id2)
141 {
142 	if (snd_ctl_elem_id_get_interface(id1) !=
143 	    snd_ctl_elem_id_get_interface(id2))
144 		return 0;
145 	if (snd_ctl_elem_id_get_device(id1) !=
146 	    snd_ctl_elem_id_get_device(id2))
147 		return 0;
148 	if (snd_ctl_elem_id_get_subdevice(id1) !=
149 	    snd_ctl_elem_id_get_subdevice(id2))
150 		return 0;
151 	if (strcmp(snd_ctl_elem_id_get_name(id1),
152 		   snd_ctl_elem_id_get_name(id2)) != 0)
153 		return 0;
154 	if (snd_ctl_elem_id_get_index(id1) !=
155 	    snd_ctl_elem_id_get_index(id2))
156 		return 0;
157 	return 1;
158 }
159 
control_init1(struct loopback_handle * lhandle,struct loopback_control * ctl)160 static int control_init1(struct loopback_handle *lhandle,
161 			 struct loopback_control *ctl)
162 {
163 	int err;
164 
165 	snd_ctl_elem_info_set_id(ctl->info, ctl->id);
166 	snd_ctl_elem_value_set_id(ctl->value, ctl->id);
167 	if (lhandle->ctl == NULL) {
168 		logit(LOG_WARNING, "Unable to read control info for '%s'\n", id_str(ctl->id));
169 		return -EIO;
170 	}
171 	err = snd_ctl_elem_info(lhandle->ctl, ctl->info);
172 	if (err < 0) {
173 		logit(LOG_WARNING, "Unable to read control info '%s': %s\n", id_str(ctl->id), snd_strerror(err));
174 		return err;
175 	}
176 	err = snd_ctl_elem_read(lhandle->ctl, ctl->value);
177 	if (err < 0) {
178 		logit(LOG_WARNING, "Unable to read control value (init1) '%s': %s\n", id_str(ctl->id), snd_strerror(err));
179 		return err;
180 	}
181 	return 0;
182 }
183 
copy_value(struct loopback_control * dst,struct loopback_control * src)184 static int copy_value(struct loopback_control *dst,
185 		      struct loopback_control *src)
186 {
187 	snd_ctl_elem_type_t type;
188 	unsigned int count;
189 	int i;
190 
191 	type = snd_ctl_elem_info_get_type(dst->info);
192 	count = snd_ctl_elem_info_get_count(dst->info);
193 	switch (type) {
194 	case SND_CTL_ELEM_TYPE_BOOLEAN:
195 		for (i = 0; i < count; i++)
196 			snd_ctl_elem_value_set_boolean(dst->value,
197 				i, snd_ctl_elem_value_get_boolean(src->value, i));
198 		break;
199 	case SND_CTL_ELEM_TYPE_INTEGER:
200 		for (i = 0; i < count; i++) {
201 			snd_ctl_elem_value_set_integer(dst->value,
202 				i, snd_ctl_elem_value_get_integer(src->value, i));
203 		}
204 		break;
205 	default:
206 		logit(LOG_CRIT, "Unable to copy control value for type %s\n", snd_ctl_elem_type_name(type));
207 		return -EINVAL;
208 	}
209 	return 0;
210 }
211 
oss_set(struct loopback * loop,struct loopback_ossmixer * ossmix,int enable)212 static int oss_set(struct loopback *loop,
213 		   struct loopback_ossmixer *ossmix,
214 		   int enable)
215 {
216 	char buf[128], file[128];
217 	int fd;
218 
219 	if (loop->capt->card_number < 0)
220 		return 0;
221 	if (!enable) {
222 		sprintf(buf, "%s \"\" 0\n", ossmix->oss_id);
223 	} else {
224 		sprintf(buf, "%s \"%s\" %i\n", ossmix->oss_id, ossmix->alsa_id, ossmix->alsa_index);
225 	}
226 	sprintf(file, "/proc/asound/card%i/oss_mixer", loop->capt->card_number);
227 	if (verbose)
228 		snd_output_printf(loop->output, "%s: Initialize OSS volume %s: %s", loop->id, file, buf);
229 	fd = open(file, O_WRONLY);
230 	if (fd >= 0 && write(fd, buf, strlen(buf)) == strlen(buf)) {
231 		close(fd);
232 		return 0;
233 	}
234 	if (fd >= 0)
235 		close(fd);
236 	logit(LOG_INFO, "%s: Unable to initialize OSS Mixer ID '%s'\n", loop->id, ossmix->oss_id);
237 	return -1;
238 }
239 
control_init2(struct loopback * loop,struct loopback_mixer * mix)240 static int control_init2(struct loopback *loop,
241 			 struct loopback_mixer *mix)
242 {
243 	snd_ctl_elem_type_t type;
244 	unsigned int count;
245 	int err;
246 
247 	snd_ctl_elem_info_copy(mix->dst.info, mix->src.info);
248 	snd_ctl_elem_info_set_id(mix->dst.info, mix->dst.id);
249 	snd_ctl_elem_value_clear(mix->dst.value);
250 	snd_ctl_elem_value_set_id(mix->dst.value, mix->dst.id);
251 	type = snd_ctl_elem_info_get_type(mix->dst.info);
252 	count = snd_ctl_elem_info_get_count(mix->dst.info);
253 	snd_ctl_elem_remove(loop->capt->ctl, mix->dst.id);
254 	switch (type) {
255 	case SND_CTL_ELEM_TYPE_BOOLEAN:
256 		err = snd_ctl_elem_add_boolean(loop->capt->ctl,
257 					       mix->dst.id, count);
258 		copy_value(&mix->dst, &mix->src);
259 		break;
260 	case SND_CTL_ELEM_TYPE_INTEGER:
261 		err = snd_ctl_elem_add_integer(loop->capt->ctl,
262 				mix->dst.id, count,
263 				snd_ctl_elem_info_get_min(mix->dst.info),
264 				snd_ctl_elem_info_get_max(mix->dst.info),
265 				snd_ctl_elem_info_get_step(mix->dst.info));
266 		copy_value(&mix->dst, &mix->src);
267 		break;
268 	default:
269 		logit(LOG_CRIT, "Unable to handle control type %s\n", snd_ctl_elem_type_name(type));
270 		err = -EINVAL;
271 		break;
272 	}
273 	if (err < 0) {
274 		logit(LOG_CRIT, "Unable to create control '%s': %s\n", id_str(mix->dst.id), snd_strerror(err));
275 		return err;
276 	}
277 	err = snd_ctl_elem_unlock(loop->capt->ctl, mix->dst.id);
278 	if (err < 0) {
279 		logit(LOG_CRIT, "Unable to unlock control info '%s': %s\n", id_str(mix->dst.id), snd_strerror(err));
280 		return err;
281 	}
282 	err = snd_ctl_elem_info(loop->capt->ctl, mix->dst.info);
283 	if (err < 0) {
284 		logit(LOG_CRIT, "Unable to read control info '%s': %s\n", id_str(mix->dst.id), snd_strerror(err));
285 		return err;
286 	}
287 	if (snd_ctl_elem_info_is_tlv_writable(mix->dst.info)) {
288 		unsigned int tlv[64];
289 		err = snd_ctl_elem_tlv_read(loop->play->ctl,
290 					    mix->src.id,
291 					    tlv, sizeof(tlv));
292 		if (err < 0) {
293 			logit(LOG_CRIT, "Unable to read TLV for '%s': %s\n", id_str(mix->src.id), snd_strerror(err));
294 			tlv[0] = tlv[1] = 0;
295 		}
296 		err = snd_ctl_elem_tlv_write(loop->capt->ctl,
297 					     mix->dst.id,
298 					     tlv);
299 		if (err < 0) {
300 			logit(LOG_CRIT, "Unable to write TLV for '%s': %s\n", id_str(mix->src.id), snd_strerror(err));
301 			return err;
302 		}
303 	}
304 	err = snd_ctl_elem_write(loop->capt->ctl, mix->dst.value);
305 	if (err < 0) {
306 		logit(LOG_CRIT, "Unable to write control value '%s': %s\n", id_str(mix->dst.id), snd_strerror(err));
307 		return err;
308 	}
309 	return 0;
310 }
311 
control_init(struct loopback * loop)312 int control_init(struct loopback *loop)
313 {
314 	struct loopback_mixer *mix;
315 	struct loopback_ossmixer *ossmix;
316 	int err;
317 
318 	for (ossmix = loop->oss_controls; ossmix; ossmix = ossmix->next)
319 		oss_set(loop, ossmix, 0);
320 	for (mix = loop->controls; mix; mix = mix->next) {
321 		err = control_init1(loop->play, &mix->src);
322 		if (err < 0) {
323 			logit(LOG_WARNING, "%s: Disabling playback control '%s'\n", loop->id, id_str(mix->src.id));
324 			mix->skip = 1;
325 			continue;
326 		}
327 		err = control_init2(loop, mix);
328 		if (err < 0)
329 			return err;
330 	}
331 	for (ossmix = loop->oss_controls; ossmix; ossmix = ossmix->next) {
332 		err = oss_set(loop, ossmix, 1);
333 		if (err < 0) {
334 			ossmix->skip = 1;
335 			logit(LOG_WARNING, "%s: Disabling OSS mixer ID '%s'\n", loop->id, ossmix->oss_id);
336 		}
337 	}
338 	return 0;
339 }
340 
control_done(struct loopback * loop)341 int control_done(struct loopback *loop)
342 {
343 	struct loopback_mixer *mix;
344 	struct loopback_ossmixer *ossmix;
345 	int err;
346 
347 	if (loop->capt->ctl == NULL)
348 		return 0;
349 	for (ossmix = loop->oss_controls; ossmix; ossmix = ossmix->next) {
350 		err = oss_set(loop, ossmix, 0);
351 		if (err < 0)
352 			logit(LOG_WARNING, "%s: Unable to remove OSS control '%s'\n", loop->id, ossmix->oss_id);
353 	}
354 	for (mix = loop->controls; mix; mix = mix->next) {
355 		if (mix->skip)
356 			continue;
357 		err = snd_ctl_elem_remove(loop->capt->ctl, mix->dst.id);
358 		if (err < 0)
359 			logit(LOG_WARNING, "%s: Unable to remove control '%s': %s\n", loop->id, id_str(mix->dst.id), snd_strerror(err));
360 	}
361 	return 0;
362 }
363 
control_event1(struct loopback * loop,struct loopback_mixer * mix,snd_ctl_event_t * ev,int capture)364 static int control_event1(struct loopback *loop,
365 			  struct loopback_mixer *mix,
366 			  snd_ctl_event_t *ev,
367 			  int capture)
368 {
369 	unsigned int mask = snd_ctl_event_elem_get_mask(ev);
370 	int err;
371 
372 	if (mask == SND_CTL_EVENT_MASK_REMOVE)
373 		return 0;
374 	if ((mask & SND_CTL_EVENT_MASK_VALUE) == 0)
375 		return 0;
376 	if (!capture) {
377 		snd_ctl_elem_value_set_id(mix->src.value, mix->src.id);
378 		err = snd_ctl_elem_read(loop->play->ctl, mix->src.value);
379 		if (err < 0) {
380 			logit(LOG_CRIT, "Unable to read control value (event1) '%s': %s\n", id_str(mix->src.id), snd_strerror(err));
381 			return err;
382 		}
383 		copy_value(&mix->dst, &mix->src);
384 		err = snd_ctl_elem_write(loop->capt->ctl, mix->dst.value);
385 		if (err < 0) {
386 			logit(LOG_CRIT, "Unable to write control value (event1) '%s': %s\n", id_str(mix->dst.id), snd_strerror(err));
387 			return err;
388 		}
389 	} else {
390 		err = snd_ctl_elem_read(loop->capt->ctl, mix->dst.value);
391 		if (err < 0) {
392 			logit(LOG_CRIT, "Unable to read control value (event2) '%s': %s\n", id_str(mix->dst.id), snd_strerror(err));
393 			return err;
394 		}
395 		copy_value(&mix->src, &mix->dst);
396 		err = snd_ctl_elem_write(loop->play->ctl, mix->src.value);
397 		if (err < 0) {
398 			logit(LOG_CRIT, "Unable to write control value (event2) '%s': %s\n", id_str(mix->src.id), snd_strerror(err));
399 			return err;
400 		}
401 	}
402 	return 0;
403 }
404 
control_event(struct loopback_handle * lhandle,snd_ctl_event_t * ev)405 int control_event(struct loopback_handle *lhandle, snd_ctl_event_t *ev)
406 {
407 	snd_ctl_elem_id_t *id2;
408 	struct loopback_mixer *mix;
409 	int capt = lhandle == lhandle->loopback->capt;
410 	int err;
411 
412 	snd_ctl_elem_id_alloca(&id2);
413 	snd_ctl_event_elem_get_id(ev, id2);
414 	for (mix = lhandle->loopback->controls; mix; mix = mix->next) {
415 		if (mix->skip)
416 			continue;
417 		if (control_id_match(id2, capt ? mix->dst.id : mix->src.id)) {
418 			err = control_event1(lhandle->loopback, mix, ev, capt);
419 			if (err < 0)
420 				return err;
421 		}
422 	}
423 	return 0;
424 }
425