xref: /illumos-gate/usr/src/cmd/devfsadm/audio_link.c (revision d67944fbe3fa0b31893a7116a09b0718eecf6078)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #include <regex.h>
27 #include <devfsadm.h>
28 #include <strings.h>
29 #include <ctype.h>
30 #include <stdlib.h>
31 #include <limits.h>
32 #include <stdio.h>
33 #include <syslog.h>
34 #include <bsm/devalloc.h>
35 #include <sys/audio.h>
36 #include <sys/soundcard.h>
37 #include <unistd.h>
38 
39 #define	MAX_AUDIO_LINK 100
40 #define	RE_SIZE 64
41 
42 extern int system_labeled;
43 
44 static void check_audio_link(char *secondary_link,
45     const char *primary_link_format);
46 
47 static int audio_process(di_minor_t minor, di_node_t node);
48 static int sndstat_process(di_minor_t minor, di_node_t node);
49 
50 static devfsadm_create_t audio_cbt[] = {
51 	{ "audio", "ddi_audio", NULL,
52 	    TYPE_EXACT, ILEVEL_0, audio_process
53 	},
54 	{ "pseudo", "ddi_pseudo", "audio",
55 	    TYPE_EXACT|DRV_EXACT, ILEVEL_0, sndstat_process
56 	},
57 };
58 
59 DEVFSADM_CREATE_INIT_V0(audio_cbt);
60 
61 /*
62  * the following can't be one big RE with a bunch of alterations "|"
63  * because recurse_dev_re() would not work.
64  */
65 static devfsadm_remove_t audio_remove_cbt[] = {
66 	/*
67 	 * Secondary links.
68 	 */
69 
70 	/* /dev/audio, /dev/audioctl, /dev/dsp */
71 	{ "audio", "^(audio|audioctl|dsp)$",
72 	    RM_POST|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_link
73 	},
74 	/* /dev/mixer0, /dev/dsp0 */
75 	{ "audio", "^(mixer|dsp)[0-9]+$",
76 	    RM_POST|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_link
77 	},
78 	/* /dev/sound/0, 0ctl */
79 	{ "audio", "^sound/[0-9]+(ctl)?$",
80 	    RM_POST|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_link
81 	},
82 	/* /dev/mixer */
83 	{ "pseudo", "^(mixer)$",
84 	    RM_POST|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_link
85 	},
86 
87 	/*
88 	 * Primary links.
89 	 */
90 
91 	/* /dev/sndstat */
92 	{ "pseudo", "^sndstat$",
93 	    RM_PRE|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_all
94 	},
95 	/* /dev/sound/audio810:0, 0ctl, etc */
96 	{ "audio", "^sound/.*:[0-9]+(ctl|dsp|mixer)?$",
97 	    RM_PRE|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_all
98 	},
99 };
100 
101 DEVFSADM_REMOVE_INIT_V0(audio_remove_cbt);
102 
103 int
104 minor_fini(void)
105 {
106 	check_audio_link("audio", "sound/%d");
107 	check_audio_link("audioctl", "sound/%dctl");
108 	check_audio_link("dsp", "dsp%d");
109 	return (DEVFSADM_SUCCESS);
110 }
111 
112 
113 #define	COPYSUB(to, from, pm, pos) (void) strncpy(to, &from[pm[pos].rm_so], \
114 		    pm[pos].rm_eo - pm[pos].rm_so); \
115 		    to[pm[pos].rm_eo - pm[pos].rm_so] = 0;
116 
117 static void
118 send_number(long num)
119 {
120 	char		buf[PATH_MAX+1];
121 
122 	/*
123 	 * This is not safe with -r.
124 	 */
125 	if (strcmp(devfsadm_root_path(), "/") != 0)
126 		return;
127 
128 	(void) snprintf(buf, sizeof (buf), "/dev/mixer%ld", num);
129 	if (device_exists(buf)) {
130 		int	fd;
131 
132 		if ((fd = open(buf, O_RDWR)) < 0)
133 			return;
134 
135 		(void) ioctl(fd, SNDCTL_SUN_SEND_NUMBER, &num);
136 		(void) close(fd);
137 		devfsadm_print(CHATTY_MID,
138 		    "sent devnum audio %ld to %s\n", num, buf);
139 	}
140 }
141 
142 static void
143 send_all(void)
144 {
145 	/*
146 	 * This module traverses /dev/sound to look for nodes that
147 	 * have been previously created.
148 	 */
149 	finddevhdl_t	fh;
150 	const char	*path;
151 
152 	/*
153 	 * This is not safe with -r.
154 	 */
155 	if ((strcmp(devfsadm_root_path(), "/") == 0) &&
156 	    (finddev_readdir("/dev", &fh) == 0)) {
157 		static int	doneit = 0;
158 
159 		while ((!doneit) && ((path = finddev_next(fh)) != NULL)) {
160 			long num;
161 			char *ep;
162 			if ((strncmp(path, "mixer", 5) != 0) ||
163 			    (!isdigit(path[5]))) {
164 				continue;
165 			}
166 			num = strtol(path + 5, &ep, 10);
167 			send_number(num);
168 		}
169 		finddev_close(fh);
170 		doneit = 1;
171 	}
172 }
173 
174 static int
175 sndstat_process(di_minor_t minor, di_node_t node)
176 {
177 	char *mn;
178 
179 	mn = di_minor_name(minor);
180 
181 	/*
182 	 * "Special" handling for /dev/sndstat and /dev/mixer.
183 	 */
184 	if (strcmp(mn, "sound,sndstat0") == 0) {
185 		(void) devfsadm_mklink("sndstat", node, minor, 0);
186 		(void) devfsadm_secondary_link("mixer", "sndstat", 0);
187 		send_all();
188 	}
189 
190 	return (DEVFSADM_CONTINUE);
191 }
192 
193 /*
194  * This function is called for every audio node.
195  * Calls enumerate to assign a logical unit id, and then
196  * devfsadm_mklink to make the link.
197  */
198 static int
199 audio_process(di_minor_t minor, di_node_t node)
200 {
201 	int flags = 0;
202 	char devpath[PATH_MAX + 1];
203 	char newpath[PATH_MAX + 1];
204 	char *buf;
205 	char *mn;
206 	char *tmp;
207 	char *ep;
208 	char re_string[RE_SIZE+1];
209 	devfsadm_enumerate_t rules[1] = {NULL};
210 
211 	if (system_labeled)
212 		flags = DA_ADD|DA_AUDIO;
213 
214 	mn = di_minor_name(minor);
215 
216 	if ((tmp = di_devfs_path(node)) == NULL) {
217 		return (DEVFSADM_CONTINUE);
218 	}
219 	(void) snprintf(devpath, sizeof (devpath), "%s:%s", tmp, mn);
220 	di_devfs_path_free(tmp);
221 
222 	/*
223 	 * "Special" handling for /dev/sndstat and /dev/mixer.
224 	 */
225 	if (strcmp(mn, "sound,sndstat0") == 0) {
226 		(void) strlcpy(newpath, "sound/sndstat", sizeof (newpath));
227 
228 		(void) devfsadm_mklink(newpath, node, minor, flags);
229 		(void) devfsadm_secondary_link("sndstat", newpath, flags);
230 		(void) devfsadm_secondary_link("mixer", newpath, flags);
231 		send_all();
232 		return (DEVFSADM_CONTINUE);
233 	}
234 
235 	if (strncmp(mn, "sound,", 6) == 0) {
236 		char base[PATH_MAX + 1];
237 		char linksrc[PATH_MAX + 1];
238 		char linkdst[PATH_MAX + 1];
239 		long num;
240 		long inst;
241 		int i;
242 		char *driver;
243 
244 		/* strlen("sound,") */
245 		(void) strlcpy(base, mn + 6, sizeof (base));
246 		mn = base;
247 
248 		driver = di_driver_name(node);
249 
250 		/* if driver name override in minor name */
251 		if ((tmp = strchr(mn, ',')) != NULL) {
252 			driver = mn;
253 			*tmp = '\0';
254 			mn = tmp + 1;
255 		}
256 
257 		/* skip past "audio" portion of the minor name */
258 		if (strncmp(mn, "audio", 5) == 0) {
259 			mn += 5;
260 		}
261 
262 		/* parse the instance number */
263 		for (i = strlen(mn); i; i--) {
264 			if (!isdigit(mn[i - 1]))
265 				break;
266 		}
267 		inst = strtol(mn + i, &ep, 10);
268 		mn[i] = 0;	/* lop off the instance number */
269 
270 		/*
271 		 * First we create a node with the driver under /dev/sound.
272 		 * Note that "instance numbers" used by the audio framework
273 		 * are guaranteed to be unique for each driver.
274 		 */
275 		(void) snprintf(newpath, sizeof (newpath), "sound/%s:%d%s",
276 		    driver, inst, mn);
277 		(void) devfsadm_mklink(newpath, node, minor, flags);
278 
279 		/*
280 		 * The rest of this logic is a gross simplification that
281 		 * is made possible by the fact that each audio node will
282 		 * have several different minors associated with it.  Rather
283 		 * processing each node separately, we just create the links
284 		 * all at once.
285 		 *
286 		 * This reduces the chances of the various links being out
287 		 * of sync with each other.
288 		 */
289 		if (strcmp(mn, "mixer") != 0) {
290 			return (DEVFSADM_CONTINUE);
291 		}
292 
293 		/*
294 		 * Its the control node, so create the various
295 		 * secondary links.
296 		 */
297 
298 		/*
299 		 * We want a match against the physical path
300 		 * without the minor name component.
301 		 */
302 		(void) snprintf(re_string, RE_SIZE, "%s", "^mixer([0-9]+)");
303 		rules[0].re = re_string;
304 		rules[0].subexp = 1;
305 		rules[0].flags = MATCH_ALL;
306 
307 		/*
308 		 * enumerate finds the logical audio id, and stuffs
309 		 * it in buf
310 		 */
311 		(void) strlcpy(devpath, newpath, sizeof (devpath));
312 		if (devfsadm_enumerate_int(devpath, 0, &buf, rules, 1)) {
313 			return (DEVFSADM_CONTINUE);
314 		}
315 		num = strtol(buf, &ep, 10);
316 		free(buf);
317 
318 		/* /dev/sound/0 */
319 		(void) snprintf(linksrc, sizeof (linksrc), "sound/%s:%ld",
320 		    driver, inst);
321 		(void) snprintf(linkdst, sizeof (linkdst), "sound/%ld", num);
322 		(void) devfsadm_secondary_link(linkdst, linksrc, flags);
323 
324 		(void) snprintf(linksrc, sizeof (linksrc), "sound/%s:%ldctl",
325 		    driver, inst);
326 		(void) snprintf(linkdst, sizeof (linkdst), "sound/%ldctl", num);
327 		(void) devfsadm_secondary_link(linkdst, linksrc, flags);
328 
329 		(void) snprintf(linksrc, sizeof (linksrc), "sound/%s:%lddsp",
330 		    driver, inst);
331 		(void) snprintf(linkdst, sizeof (linkdst), "dsp%ld", num);
332 		(void) devfsadm_secondary_link(linkdst, linksrc, flags);
333 
334 		(void) snprintf(linksrc, sizeof (linksrc), "sound/%s:%ldmixer",
335 		    driver, inst);
336 		(void) snprintf(linkdst, sizeof (linkdst), "mixer%ld", num);
337 		(void) devfsadm_secondary_link(linkdst, linksrc, flags);
338 
339 		/* Send control number */
340 		send_number(num);
341 
342 		return (DEVFSADM_CONTINUE);
343 	}
344 
345 	if (strncmp(mn, "internal,", 9) == 0) {
346 		/* we don't set up internal nodes in /dev */
347 		return (DEVFSADM_CONTINUE);
348 	}
349 
350 	devfsadm_errprint("SUNW_audio_link: can't find match for'%s'\n", mn);
351 	return (DEVFSADM_CONTINUE);
352 }
353 
354 static void
355 check_audio_link(char *secondary, const char *primary_format)
356 {
357 	char primary[PATH_MAX + 1];
358 	int i;
359 	int flags = 0;
360 
361 	/* if link is present, return */
362 	if (devfsadm_link_valid(secondary) == DEVFSADM_TRUE) {
363 		return;
364 	}
365 
366 	if (system_labeled)
367 		flags = DA_ADD|DA_AUDIO;
368 
369 	for (i = 0; i < MAX_AUDIO_LINK; i++) {
370 		(void) sprintf(primary, primary_format, i);
371 		if (devfsadm_link_valid(primary) == DEVFSADM_TRUE) {
372 			/* we read link to get it to the master "real" link */
373 			(void) devfsadm_secondary_link(secondary,
374 			    primary, flags);
375 			break;
376 		}
377 	}
378 }
379