xref: /illumos-gate/usr/src/cmd/devfsadm/audio_link.c (revision ae1049320dd687abe67d8ed2ce29f4d478f64841)
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$",
72 	    RM_POST|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_all
73 	},
74 	{ "audio", "^audioctl$",
75 	    RM_POST|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_all
76 	},
77 	{ "audio", "^dsp$",
78 	    RM_POST|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_all
79 	},
80 	{ "audio", "^mixer",
81 	    RM_POST|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_all
82 	},
83 	{ "audio", "^sndstat$",
84 	    RM_PRE|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_all
85 	},
86 	{ "audio", "^mixer[0-9]+$",
87 	    RM_POST|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_all
88 	},
89 	{ "audio", "^dsp[0-9]+$",
90 	    RM_POST|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_all
91 	},
92 	{ "audio", "^sound/[0-9]+$",
93 	    RM_POST|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_all
94 	},
95 	{ "audio", "^sound/[0-9]+ctl$",
96 	    RM_POST|RM_HOT|RM_ALWAYS, ILEVEL_0, devfsadm_rm_all
97 	},
98 };
99 
100 DEVFSADM_REMOVE_INIT_V0(audio_remove_cbt);
101 
102 int
103 minor_fini(void)
104 {
105 	check_audio_link("audio", "sound/%d");
106 	check_audio_link("audioctl", "sound/%dctl");
107 	check_audio_link("dsp", "dsp%d");
108 	return (DEVFSADM_SUCCESS);
109 }
110 
111 
112 #define	COPYSUB(to, from, pm, pos) (void) strncpy(to, &from[pm[pos].rm_so], \
113 		    pm[pos].rm_eo - pm[pos].rm_so); \
114 		    to[pm[pos].rm_eo - pm[pos].rm_so] = 0;
115 
116 static void
117 send_number(long num)
118 {
119 	char		buf[PATH_MAX+1];
120 
121 	/*
122 	 * This is not safe with -r.
123 	 */
124 	if (strcmp(devfsadm_root_path(), "/") != 0)
125 		return;
126 
127 	(void) snprintf(buf, sizeof (buf), "/dev/mixer%ld", num);
128 	if (device_exists(buf)) {
129 		int	fd;
130 
131 		if ((fd = open(buf, O_RDWR)) < 0)
132 			return;
133 
134 		(void) ioctl(fd, SNDCTL_SUN_SEND_NUMBER, &num);
135 		(void) close(fd);
136 		devfsadm_print(CHATTY_MID,
137 		    "sent devnum audio %ld to %s\n", num, buf);
138 	}
139 }
140 
141 static int
142 sndstat_process(di_minor_t minor, di_node_t node)
143 {
144 	char *mn;
145 
146 	mn = di_minor_name(minor);
147 
148 	/*
149 	 * "Special" handling for /dev/sndstat and /dev/mixer.
150 	 */
151 	if (strcmp(mn, "sound,sndstat0") == 0) {
152 		(void) devfsadm_mklink("sndstat", node, minor, 0);
153 		(void) devfsadm_secondary_link("mixer", "sndstat", 0);
154 	}
155 
156 	return (DEVFSADM_CONTINUE);
157 }
158 
159 /*
160  * This function is called for every audio node.
161  * Calls enumerate to assign a logical unit id, and then
162  * devfsadm_mklink to make the link.
163  */
164 static int
165 audio_process(di_minor_t minor, di_node_t node)
166 {
167 	int flags = 0;
168 	char devpath[PATH_MAX + 1];
169 	char newpath[PATH_MAX + 1];
170 	char *buf;
171 	char *mn;
172 	char *tmp;
173 	char *ep;
174 	char re_string[RE_SIZE+1];
175 	devfsadm_enumerate_t rules[1] = {NULL};
176 	char base[PATH_MAX + 1];
177 	char linksrc[PATH_MAX + 1];
178 	char linkdst[PATH_MAX + 1];
179 	long num;
180 	long inst;
181 	int i;
182 	char *driver;
183 
184 	if (system_labeled)
185 		flags = DA_ADD|DA_AUDIO;
186 
187 	mn = di_minor_name(minor);
188 
189 	if ((tmp = di_devfs_path(node)) == NULL) {
190 		return (DEVFSADM_CONTINUE);
191 	}
192 	(void) snprintf(devpath, sizeof (devpath), "%s:%s", tmp, mn);
193 	di_devfs_path_free(tmp);
194 
195 	if (strncmp(mn, "sound,", sizeof ("sound,") - 1) != 0) {
196 		devfsadm_errprint("SUNW_audio_link: "
197 		    "can't find match for'%s'\n", mn);
198 		return (DEVFSADM_CONTINUE);
199 	}
200 
201 	/* strlen("sound,") */
202 	(void) strlcpy(base, mn + 6, sizeof (base));
203 	mn = base;
204 
205 	driver = di_driver_name(node);
206 
207 	/* if driver name override in minor name */
208 	if ((tmp = strchr(mn, ',')) != NULL) {
209 		driver = mn;
210 		*tmp = '\0';
211 		mn = tmp + 1;
212 	}
213 
214 	/* skip past "audio" portion of the minor name */
215 	if (strncmp(mn, "audio", sizeof ("audio") - 1) == 0) {
216 		mn += sizeof ("audio") - 1;
217 	}
218 
219 	/* parse the instance number */
220 	for (i = strlen(mn); i; i--) {
221 		if (!isdigit(mn[i - 1]))
222 			break;
223 	}
224 	inst = strtol(mn + i, &ep, 10);
225 	mn[i] = 0;	/* lop off the instance number */
226 
227 	/*
228 	 * First we create a node with the driver under /dev/sound.
229 	 * Note that "instance numbers" used by the audio framework
230 	 * are guaranteed to be unique for each driver.
231 	 */
232 	(void) snprintf(newpath, sizeof (newpath), "sound/%s:%d%s",
233 	    driver, inst, mn);
234 	(void) devfsadm_mklink(newpath, node, minor, flags);
235 
236 	/*
237 	 * The rest of this logic is a gross simplification that is
238 	 * made possible by the fact that each audio node will have
239 	 * several different minors associated with it.  Rather than
240 	 * processing each node separately, we just create the links
241 	 * all at once.
242 	 *
243 	 * This reduces the chances of the various links being out of
244 	 * sync with each other.
245 	 */
246 	if (strcmp(mn, "mixer") != 0) {
247 		return (DEVFSADM_CONTINUE);
248 	}
249 
250 	/*
251 	 * Its the control node, so create the various
252 	 * secondary links.
253 	 */
254 
255 	/*
256 	 * We want a match against the physical path
257 	 * without the minor name component.
258 	 */
259 	(void) snprintf(re_string, RE_SIZE, "%s", "^mixer([0-9]+)");
260 	rules[0].re = re_string;
261 	rules[0].subexp = 1;
262 	rules[0].flags = MATCH_ALL;
263 
264 	/*
265 	 * enumerate finds the logical audio id, and stuffs
266 	 * it in buf
267 	 */
268 	(void) strlcpy(devpath, newpath, sizeof (devpath));
269 	if (devfsadm_enumerate_int(devpath, 0, &buf, rules, 1)) {
270 		return (DEVFSADM_CONTINUE);
271 	}
272 	num = strtol(buf, &ep, 10);
273 	free(buf);
274 
275 	/* /dev/sound/0 */
276 	(void) snprintf(linksrc, sizeof (linksrc), "sound/%s:%ld",
277 	    driver, inst);
278 	(void) snprintf(linkdst, sizeof (linkdst), "sound/%ld", num);
279 	(void) devfsadm_secondary_link(linkdst, linksrc, flags);
280 
281 	(void) snprintf(linksrc, sizeof (linksrc), "sound/%s:%ldctl",
282 	    driver, inst);
283 	(void) snprintf(linkdst, sizeof (linkdst), "sound/%ldctl", num);
284 	(void) devfsadm_secondary_link(linkdst, linksrc, flags);
285 
286 	(void) snprintf(linksrc, sizeof (linksrc), "sound/%s:%lddsp",
287 	    driver, inst);
288 	(void) snprintf(linkdst, sizeof (linkdst), "dsp%ld", num);
289 	(void) devfsadm_secondary_link(linkdst, linksrc, flags);
290 
291 	(void) snprintf(linksrc, sizeof (linksrc), "sound/%s:%ldmixer",
292 	    driver, inst);
293 	(void) snprintf(linkdst, sizeof (linkdst), "mixer%ld", num);
294 	(void) devfsadm_secondary_link(linkdst, linksrc, flags);
295 
296 	/* Send control number */
297 	send_number(num);
298 
299 	return (DEVFSADM_CONTINUE);
300 }
301 
302 static void
303 check_audio_link(char *secondary, const char *primary_format)
304 {
305 	char primary[PATH_MAX + 1];
306 	int i;
307 	int flags = 0;
308 
309 	/* if link is present, return */
310 	if (devfsadm_link_valid(secondary) == DEVFSADM_TRUE) {
311 		return;
312 	}
313 
314 	if (system_labeled)
315 		flags = DA_ADD|DA_AUDIO;
316 
317 	for (i = 0; i < MAX_AUDIO_LINK; i++) {
318 		(void) sprintf(primary, primary_format, i);
319 		if (devfsadm_link_valid(primary) == DEVFSADM_TRUE) {
320 			/* we read link to get it to the master "real" link */
321 			(void) devfsadm_secondary_link(secondary,
322 			    primary, flags);
323 			break;
324 		}
325 	}
326 }
327