xref: /openbsd-src/usr.sbin/config/sem.c (revision 50b7afb2c2c0993b0894d4e34bf857cb13ed9c80)
1 /*	$OpenBSD: sem.c,v 1.34 2014/05/18 09:29:54 espie Exp $	*/
2 /*	$NetBSD: sem.c,v 1.10 1996/11/11 23:40:11 gwr Exp $	*/
3 
4 /*
5  * Copyright (c) 1992, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This software was developed by the Computer Systems Engineering group
9  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
10  * contributed to Berkeley.
11  *
12  * All advertising materials mentioning features or use of this software
13  * must display the following acknowledgement:
14  *	This product includes software developed by the University of
15  *	California, Lawrence Berkeley Laboratories.
16  *
17  * Redistribution and use in source and binary forms, with or without
18  * modification, are permitted provided that the following conditions
19  * are met:
20  * 1. Redistributions of source code must retain the above copyright
21  *    notice, this list of conditions and the following disclaimer.
22  * 2. Redistributions in binary form must reproduce the above copyright
23  *    notice, this list of conditions and the following disclaimer in the
24  *    documentation and/or other materials provided with the distribution.
25  * 3. Neither the name of the University nor the names of its contributors
26  *    may be used to endorse or promote products derived from this software
27  *    without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  *	from: @(#)sem.c	8.1 (Berkeley) 6/6/93
42  */
43 
44 #include <sys/param.h>
45 
46 #include <ctype.h>
47 #include <err.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 
52 #include "config.h"
53 #include "sem.h"
54 
55 /*
56  * config semantics.
57  */
58 
59 #define	NAMESIZE	100	/* local name buffers */
60 
61 const char *s_generic;
62 const char *s_nfs;
63 
64 static struct hashtab *attrtab;		/* for attribute lookup */
65 static struct hashtab *cfhashtab;	/* for config lookup */
66 static struct hashtab *devitab;		/* etc */
67 
68 static struct attr errattr;
69 static struct devbase errdev;
70 static struct deva errdeva;
71 static struct devbase **nextbase;
72 static struct deva **nextdeva;
73 static struct config **nextcf;
74 static struct devi **nextdevi;
75 static struct devi **nextpseudo;
76 
77 static int has_errobj(struct nvlist *, void *);
78 static struct nvlist *addtoattr(struct nvlist *, struct devbase *);
79 static int exclude(struct nvlist *, const char *, const char *);
80 static int resolve(struct nvlist **, const char *, const char *,
81     struct nvlist *, int);
82 static int lresolve(struct nvlist **, const char *, const char *,
83     struct nvlist *, int);
84 static struct devi *newdevi(const char *, int, struct devbase *d);
85 static struct devi *getdevi(const char *);
86 static const char *concat(const char *, int);
87 static char *extend(char *, const char *);
88 static int split(const char *, size_t, char *, size_t, int *);
89 static void selectbase(struct devbase *, struct deva *);
90 static int onlist(struct nvlist *, void *);
91 static const char **fixloc(const char *, struct attr *, struct nvlist *);
92 
93 void
94 initsem(void)
95 {
96 
97 	attrtab = ht_new();
98 	errattr.a_name = "<internal>";
99 
100 	allbases = NULL;
101 	nextbase = &allbases;
102 
103 	alldevas = NULL;
104 	nextdeva = &alldevas;
105 
106 	cfhashtab = ht_new();
107 	allcf = NULL;
108 	nextcf = &allcf;
109 
110 	devitab = ht_new();
111 	alldevi = NULL;
112 	nextdevi = &alldevi;
113 	errdev.d_name = "<internal>";
114 
115 	allpseudo = NULL;
116 	nextpseudo = &allpseudo;
117 
118 	s_generic = intern("generic");
119 	s_nfs = intern("nfs");
120 }
121 
122 /* Name of include file just ended (set in scan.l) */
123 extern const char *lastfile;
124 
125 void
126 enddefs(void)
127 {
128 	struct devbase *dev;
129 
130 	for (dev = allbases; dev != NULL; dev = dev->d_next) {
131 		if (!dev->d_isdef) {
132 			(void)fprintf(stderr,
133 			    "%s: device `%s' used but not defined\n",
134 			    lastfile, dev->d_name);
135 			errors++;
136 			continue;
137 		}
138 	}
139 	if (errors) {
140 		(void)fprintf(stderr, "*** Stop.\n");
141 		exit(1);
142 	}
143 }
144 
145 void
146 setdefmaxusers(int min, int def, int max)
147 {
148 
149 	if (min < 1 || min > def || def > max)
150 		error("maxusers must have 1 <= min <= default <= max");
151 	else {
152 		minmaxusers = min;
153 		defmaxusers = def;
154 		maxmaxusers = max;
155 	}
156 }
157 
158 void
159 setmaxusers(int n)
160 {
161 
162 	if (maxusers != 0) {
163 		warnx("warning: duplicate maxusers parameter, will use latest definition (%d)", n);
164 	}
165 	maxusers = n;
166 	if (n < minmaxusers) {
167 		warnx("warning: minimum of %d maxusers assumed", minmaxusers);
168 		maxusers = minmaxusers;
169 	} else if (n > maxmaxusers) {
170 		warnx("warning: maxusers (%d) > %d", n, maxmaxusers);
171 	}
172 }
173 
174 /*
175  * Define an attribute, optionally with an interface (a locator list).
176  * Since an empty locator list is logically different from "no interface",
177  * all locator lists include a dummy head node, which we discard here.
178  */
179 int
180 defattr(const char *name, struct nvlist *locs)
181 {
182 	struct attr *a;
183 	struct nvlist *nv;
184 	int len;
185 
186 	a = emalloc(sizeof *a);
187 	if (ht_insert(attrtab, name, a)) {
188 		free(a);
189 		error("attribute `%s' already defined", name);
190 		nvfreel(locs);
191 		return (1);
192 	}
193 	a->a_name = name;
194 	if (locs != NULL) {
195 		a->a_iattr = 1;
196 		a->a_locs = locs->nv_next;
197 		nvfree(locs);
198 	} else {
199 		a->a_iattr = 0;
200 		a->a_locs = NULL;
201 	}
202 	len = 0;
203 	for (nv = a->a_locs; nv != NULL; nv = nv->nv_next)
204 		len++;
205 	a->a_loclen = len;
206 	a->a_devs = NULL;
207 	a->a_refs = NULL;
208 	return (0);
209 }
210 
211 /*
212  * Return true if the given `error object' is embedded in the given
213  * pointer list.
214  */
215 static int
216 has_errobj(struct nvlist *nv, void *obj)
217 {
218 
219 	for (; nv != NULL; nv = nv->nv_next)
220 		if (nv->nv_ptr == obj)
221 			return (1);
222 	return (0);
223 }
224 
225 /*
226  * Add a device base to a list in an attribute (actually, to any list).
227  * Note that this does not check for duplicates, and does reverse the
228  * list order, but no one cares anyway.
229  */
230 static struct nvlist *
231 addtoattr(struct nvlist *l, struct devbase *dev)
232 {
233 	struct nvlist *n;
234 
235 	n = newnv(NULL, NULL, dev, 0, l);
236 	return (n);
237 }
238 
239 /*
240  * Define a device.  This may (or may not) also define an interface
241  * attribute and/or refer to existing attributes.
242  */
243 void
244 defdev(struct devbase *dev, int ispseudo, struct nvlist *loclist,
245     struct nvlist *attrs)
246 {
247 	struct nvlist *nv;
248 	struct attr *a;
249 
250 	if (dev == &errdev)
251 		goto bad;
252 	if (dev->d_isdef) {
253 		error("redefinition of `%s'", dev->d_name);
254 		goto bad;
255 	}
256 	dev->d_isdef = 1;
257 	if (has_errobj(attrs, &errattr))
258 		goto bad;
259 
260 	/*
261 	 * Handle implicit attribute definition from locator list.  Do
262 	 * this before scanning the `at' list so that we can have, e.g.:
263 	 *	device foo at other, foo { slot = -1 }
264 	 * (where you can plug in a foo-bus extender to a foo-bus).
265 	 */
266 	if (loclist != NULL) {
267 		nv = loclist;
268 		loclist = NULL;	/* defattr disposes of them for us */
269 		if (defattr(dev->d_name, nv))
270 			goto bad;
271 		attrs = newnv(dev->d_name, NULL, getattr(dev->d_name), 0,
272 		    attrs);
273 	}
274 
275 	/* Committed!  Set up fields. */
276 	dev->d_ispseudo = ispseudo;
277 	dev->d_attrs = attrs;
278 
279 	/*
280 	 * For each interface attribute this device refers to, add this
281 	 * device to its reference list.  This makes, e.g., finding all
282 	 * "scsi"s easier.
283 	 */
284 	for (nv = attrs; nv != NULL; nv = nv->nv_next) {
285 		a = nv->nv_ptr;
286 		if (a->a_iattr)
287 			a->a_refs = addtoattr(a->a_refs, dev);
288 	}
289 	return;
290 bad:
291 	nvfreel(loclist);
292 	nvfreel(attrs);
293 }
294 
295 /*
296  * Look up a devbase.  Also makes sure it is a reasonable name,
297  * i.e., does not end in a digit or contain special characters.
298  */
299 struct devbase *
300 getdevbase(char *name)
301 {
302 	u_char *p;
303 	struct devbase *dev;
304 
305 	p = (u_char *)name;
306 	if (!isalpha(*p))
307 		goto badname;
308 	while (*++p) {
309 		if (!isalnum(*p) && *p != '_')
310 			goto badname;
311 	}
312 	if (isdigit(*--p)) {
313 badname:
314 		error("bad device base name `%s'", name);
315 		return (&errdev);
316 	}
317 	dev = ht_lookup(devbasetab, name);
318 	if (dev == NULL) {
319 		dev = emalloc(sizeof *dev);
320 		dev->d_name = name;
321 		dev->d_next = NULL;
322 		dev->d_isdef = 0;
323 		dev->d_major = NODEV;
324 		dev->d_attrs = NULL;
325 		dev->d_ihead = NULL;
326 		dev->d_ipp = &dev->d_ihead;
327 		dev->d_ahead = NULL;
328 		dev->d_app = &dev->d_ahead;
329 		dev->d_umax = 0;
330 		*nextbase = dev;
331 		nextbase = &dev->d_next;
332 		if (ht_insert(devbasetab, name, dev))
333 			panic("getdevbase(%s)", name);
334 	}
335 	return (dev);
336 }
337 
338 /*
339  * Define some of a device's allowable parent attachments.
340  * There may be a list of (plain) attributes.
341  */
342 void
343 defdevattach(struct deva *deva, struct devbase *dev, struct nvlist *atlist,
344     struct nvlist *attrs)
345 {
346 	struct nvlist *nv;
347 	struct attr *a;
348 	struct deva *da;
349 
350 	if (dev == &errdev)
351 		goto bad;
352 	if (deva == NULL)
353 		deva = getdevattach(dev->d_name);
354 	if (deva == &errdeva)
355 		goto bad;
356 	if (!dev->d_isdef) {
357 		error("attaching undefined device `%s'", dev->d_name);
358 		goto bad;
359 	}
360 	if (deva->d_isdef) {
361 		error("redefinition of `%s'", deva->d_name);
362 		goto bad;
363 	}
364 	if (dev->d_ispseudo) {
365 		error("pseudo-devices can't attach");
366 		goto bad;
367 	}
368 
369 	deva->d_isdef = 1;
370 	if (has_errobj(attrs, &errattr))
371 		goto bad;
372 	for (nv = attrs; nv != NULL; nv = nv->nv_next) {
373 		a = nv->nv_ptr;
374 		if (a == &errattr)
375 			continue;		/* already complained */
376 		if (a->a_iattr)
377 			error("`%s' is not a plain attribute", a->a_name);
378 	}
379 
380 	/* Committed!  Set up fields. */
381 	deva->d_attrs = attrs;
382 	deva->d_atlist = atlist;
383 	deva->d_devbase = dev;
384 
385 	/*
386 	 * Turn the `at' list into interface attributes (map each
387 	 * nv_name to an attribute, or to NULL for root), and add
388 	 * this device to those attributes, so that children can
389 	 * be listed at this particular device if they are supported
390 	 * by that attribute.
391 	 */
392 	for (nv = atlist; nv != NULL; nv = nv->nv_next) {
393 		if (nv->nv_name == NULL)
394 			nv->nv_ptr = a = NULL;	/* at root */
395 		else
396 			nv->nv_ptr = a = getattr(nv->nv_name);
397 		if (a == &errattr)
398 			continue;		/* already complained */
399 
400 		/*
401 		 * Make sure that an attachment spec doesn't
402 		 * already say how to attach to this attribute.
403 		 */
404 		for (da = dev->d_ahead; da != NULL; da = da->d_bsame)
405 			if (onlist(da->d_atlist, a))
406 				error("attach at `%s' already done by `%s'",
407 				    a ? a->a_name : "root", da->d_name);
408 
409 		if (a == NULL)
410 			continue;		/* at root; don't add */
411 		if (!a->a_iattr)
412 			error("%s cannot be at plain attribute `%s'",
413 			    dev->d_name, a->a_name);
414 		else
415 			a->a_devs = addtoattr(a->a_devs, dev);
416 	}
417 
418 	/* attach to parent */
419 	*dev->d_app = deva;
420 	dev->d_app = &deva->d_bsame;
421 	return;
422 bad:
423 	nvfreel(atlist);
424 	nvfreel(attrs);
425 }
426 
427 /*
428  * Look up a device attachment.  Also makes sure it is a reasonable
429  * name, i.e., does not contain digits or special characters.
430  */
431 struct deva *
432 getdevattach(const char *name)
433 {
434 	u_char *p;
435 	struct deva *deva;
436 
437 	p = (u_char *)name;
438 	if (!isalpha(*p))
439 		goto badname;
440 	while (*++p) {
441 		if (!isalnum(*p) && *p != '_')
442 			goto badname;
443 	}
444 	if (isdigit((unsigned char)*--p)) {
445 badname:
446 		error("bad device attachment name `%s'", name);
447 		return (&errdeva);
448 	}
449 	deva = ht_lookup(devatab, name);
450 	if (deva == NULL) {
451 		deva = emalloc(sizeof *deva);
452 		deva->d_name = name;
453 		deva->d_next = NULL;
454 		deva->d_bsame = NULL;
455 		deva->d_isdef = 0;
456 		deva->d_devbase = NULL;
457 		deva->d_atlist = NULL;
458 		deva->d_attrs = NULL;
459 		deva->d_ihead = NULL;
460 		deva->d_ipp = &deva->d_ihead;
461 		*nextdeva = deva;
462 		nextdeva = &deva->d_next;
463 		if (ht_insert(devatab, name, deva))
464 			panic("getdeva(%s)", name);
465 	}
466 	return (deva);
467 }
468 
469 /*
470  * Look up an attribute.
471  */
472 struct attr *
473 getattr(const char *name)
474 {
475 	struct attr *a;
476 
477 	if ((a = ht_lookup(attrtab, name)) == NULL) {
478 		error("undefined attribute `%s'", name);
479 		a = &errattr;
480 	}
481 	return (a);
482 }
483 
484 /*
485  * Set the major device number for a device, so that it can be used
486  * as a root/swap/dumps "on" device in a configuration.
487  */
488 void
489 setmajor(struct devbase *d, int n)
490 {
491 
492 	if (d != &errdev && d->d_major != NODEV)
493 		error("device `%s' is already major %d",
494 		    d->d_name, d->d_major);
495 	else
496 		d->d_major = n;
497 }
498 
499 #define ABS(x) ((x) < 0 ? -(x) : (x))
500 
501 static int
502 exclude(struct nvlist *nv, const char *name, const char *what)
503 {
504 
505 	if (nv != NULL) {
506 		error("%s: swap generic must not specify %s", name, what);
507 		return (1);
508 	}
509 	return (0);
510 }
511 
512 /*
513  * Map things like "ra0b" => makedev(major("ra"), 0*maxpartitions + 'b'-'a').
514  * Handle the case where the device number is given but there is no
515  * corresponding name, and map NULL to the default.
516  */
517 static int
518 resolve(struct nvlist **nvp, const char *name, const char *what,
519     struct nvlist *dflt, int part)
520 {
521 	struct nvlist *nv;
522 	struct devbase *dev;
523 	const char *cp;
524 	int maj, min, l;
525 	int unit;
526 	char buf[NAMESIZE];
527 
528 	part -= 'a';
529 	if ((part >= maxpartitions) || (part < 0))
530 		panic("resolve");
531 	if ((nv = *nvp) == NULL) {
532 		dev_t	d = NODEV;
533 		/*
534 		 * Apply default.  Easiest to do this by number.
535 		 * Make sure to retain NODEVness, if this is dflt's disposition.
536 		 */
537 		if (dflt->nv_int != NODEV) {
538 			maj = major(dflt->nv_int);
539 			min = (minor(dflt->nv_int) / maxpartitions) + part;
540 			d = makedev(maj, min);
541 		}
542 		*nvp = nv = newnv(NULL, NULL, NULL, d, NULL);
543 	}
544 	if (nv->nv_int != NODEV) {
545 		/*
546 		 * By the numbers.  Find the appropriate major number
547 		 * to make a name.
548 		 */
549 		maj = major(nv->nv_int);
550 		min = minor(nv->nv_int);
551 		for (dev = allbases; dev != NULL; dev = dev->d_next)
552 			if (dev->d_major == maj)
553 				break;
554 		if (dev == NULL)
555 			(void)snprintf(buf, sizeof buf, "<%d/%d>",
556 			    maj, min);
557 		else
558 			(void)snprintf(buf, sizeof buf, "%s%d%c",
559 			    dev->d_name, min / maxpartitions,
560 			    (min % maxpartitions) + 'a');
561 		nv->nv_str = intern(buf);
562 		return (0);
563 	}
564 
565 	if (nv->nv_str == NULL || nv->nv_str == s_nfs)
566 		/*
567 		 * NFS spec. Leave as NODEV.
568 		 */
569 		return (0);
570 
571 	/*
572 	 * The normal case: things like "ra2b".  Check for partition
573 	 * suffix, remove it if there, and split into name ("ra") and
574 	 * unit (2).
575 	 */
576 	l = strlen(nv->nv_str);
577 	cp = &nv->nv_str[l];
578 	if (l > 1 && *--cp >= 'a' && *cp <= 'a'+maxpartitions &&
579 	    isdigit((unsigned char)cp[-1])) {
580 		l--;
581 		part = *cp - 'a';
582 	}
583 	cp = nv->nv_str;
584 	if (split(cp, l, buf, sizeof buf, &unit)) {
585 		error("%s: invalid %s device name `%s'", name, what, cp);
586 		return (1);
587 	}
588 	dev = ht_lookup(devbasetab, intern(buf));
589 	if (dev == NULL || dev->d_major == NODEV) {
590 		error("%s: can't make %s device from `%s'",
591 		    name, what, nv->nv_str);
592 		return (1);
593 	}
594 	nv->nv_name = dev->d_name;
595 	nv->nv_int = makedev(dev->d_major, unit * maxpartitions + part);
596 	return (0);
597 }
598 
599 static int
600 lresolve(struct nvlist **nvp, const char *name, const char *what,
601     struct nvlist *dflt, int part)
602 {
603 	int err;
604 
605 	while ((err = resolve(nvp, name, what, dflt, part)) == 0 &&
606 	    (*nvp)->nv_next != NULL)
607 		nvp = &(*nvp)->nv_next;
608 	return (err);
609 }
610 
611 /*
612  * Add a completed configuration to the list.
613  */
614 void
615 addconf(struct config *cf0)
616 {
617 	struct config *cf;
618 	struct nvlist *nv;
619 	const char *name;
620 
621 	name = cf0->cf_name;
622 	cf = emalloc(sizeof *cf);
623 	if (ht_insert(cfhashtab, name, cf)) {
624 		error("configuration `%s' already defined", name);
625 		free(cf);
626 		goto bad;
627 	}
628 	*cf = *cf0;
629 
630 	/*
631 	 * Look for "swap generic".
632 	 */
633 	for (nv = cf->cf_swap; nv != NULL; nv = nv->nv_next)
634 	    if (nv->nv_str == s_generic)
635 		break;
636 	if (nv != NULL) {
637 		/*
638 		 * Make sure no root or dump device specified, and no
639 		 * other swap devices.  Note single | here (check all).
640 		 */
641 		nv = cf->cf_swap;
642 		if (exclude(cf->cf_root, name, "root device") |
643 		    exclude(nv->nv_next, name, "additional swap devices") |
644 		    exclude(cf->cf_dump, name, "dump device"))
645 			goto bad;
646 	} else {
647 		nv = cf->cf_root;
648 		if (nv == NULL) {
649 			error("%s: no root device specified", name);
650 			goto bad;
651 		}
652 		if (resolve(&cf->cf_root, name, "root", nv, 'a') |
653 		    lresolve(&cf->cf_swap, name, "swap", nv, 'b') |
654 		    resolve(&cf->cf_dump, name, "dumps", nv, 'b'))
655 			goto bad;
656 	}
657 	*nextcf = cf;
658 	nextcf = &cf->cf_next;
659 	return;
660 bad:
661 	nvfreel(cf0->cf_root);
662 	nvfreel(cf0->cf_swap);
663 	nvfreel(cf0->cf_dump);
664 }
665 
666 void
667 setconf(struct nvlist **npp, const char *what, struct nvlist *v)
668 {
669 
670 	if (*npp != NULL) {
671 		error("duplicate %s specification", what);
672 		nvfreel(v);
673 	} else
674 		*npp = v;
675 }
676 
677 static struct devi *
678 newdevi(const char *name, int unit, struct devbase *d)
679 {
680 	struct devi *i;
681 
682 	i = emalloc(sizeof *i);
683 	i->i_name = name;
684 	i->i_unit = unit;
685 	i->i_base = d;
686 	i->i_next = NULL;
687 	i->i_bsame = NULL;
688 	i->i_asame = NULL;
689 	i->i_alias = NULL;
690 	i->i_at = NULL;
691 	i->i_atattr = NULL;
692 	i->i_atdev = NULL;
693 	i->i_atdeva = NULL;
694 	i->i_locs = NULL;
695 	i->i_cfflags = 0;
696 	i->i_cfindex = -1;
697 	i->i_lineno = currentline();
698 	if (unit >= d->d_umax)
699 		d->d_umax = unit + 1;
700 	return (i);
701 }
702 
703 /*
704  * Enable an already declared but disabled device.
705  */
706 void
707 enabledev(const char *name, const char *at)
708 {
709 	struct devbase *ib, *ab;
710 	char atbuf[NAMESIZE];
711 	struct attr *attr;
712 	struct nvlist *nv;
713 	struct devi *i;
714 	const char *cp;
715 	int atunit;
716 
717 	i = ht_lookup(devitab, name);
718 	if (i == NULL) {
719 		error("invalid device `%s'", name);
720 		return;
721 	}
722 	ib = i->i_base;
723 
724 	if (split(at, strlen(at), atbuf, sizeof atbuf, &atunit)) {
725 		error("invalid attachment name `%s'", at);
726 		return;
727 	}
728 	cp = intern(atbuf);
729 	ab = ht_lookup(devbasetab, cp);
730 	if (ab == NULL) {
731 		error("invalid attachment device `%s'", cp);
732 		return;
733 	}
734 	for (nv = ab->d_attrs; nv != NULL; nv = nv->nv_next) {
735 		attr = nv->nv_ptr;
736 		if (onlist(attr->a_devs, ib))
737 			goto foundattachment;
738 	}
739 	error("%s's cannot attach to %s's", ib->d_name, atbuf);
740 	return;
741 
742 foundattachment:
743 	while (i && i->i_atdev != ab)
744 		i = i->i_alias;
745 	if (i == NULL) {
746 		error("%s at %s not found", name, at);
747 		return;
748 	} else
749 		i->i_disable = 0; /* Enable */
750 }
751 
752 /*
753  * Add the named device as attaching to the named attribute (or perhaps
754  * another device instead) plus unit number.
755  */
756 void
757 adddev(const char *name, const char *at, struct nvlist *loclist, int flags,
758     int disable)
759 {
760 	struct devi *i;	/* the new instance */
761 	struct attr *attr;	/* attribute that allows attach */
762 	struct devbase *ib;	/* i->i_base */
763 	struct devbase *ab;	/* not NULL => at another dev */
764 	struct nvlist *nv;
765 	struct deva *iba;	/* devbase attachment used */
766 	const char *cp;
767 	int atunit;
768 	char atbuf[NAMESIZE];
769 	int hit;
770 
771 	ab = NULL;
772 	iba = NULL;
773 	if (at == NULL) {
774 		/* "at root" */
775 		if ((i = getdevi(name)) == NULL)
776 			goto bad;
777 		/*
778 		 * Must warn about i_unit > 0 later, after taking care of
779 		 * the STAR cases (we could do non-star's here but why
780 		 * bother?).  Make sure this device can be at root.
781 		 */
782 		ib = i->i_base;
783 		hit = 0;
784 		for (iba = ib->d_ahead; iba != NULL; iba = iba->d_bsame)
785 			if (onlist(iba->d_atlist, NULL)) {
786 				hit = 1;
787 				break;
788 			}
789 		if (!hit) {
790 			error("%s's cannot attach to the root", ib->d_name);
791 			goto bad;
792 		}
793 		attr = &errattr;	/* a convenient "empty" attr */
794 	} else {
795 		if (split(at, strlen(at), atbuf, sizeof atbuf, &atunit)) {
796 			error("invalid attachment name `%s'", at);
797 			/* (void)getdevi(name); -- ??? */
798 			goto bad;
799 		}
800 		if ((i = getdevi(name)) == NULL)
801 			goto bad;
802 		ib = i->i_base;
803 		cp = intern(atbuf);
804 
805 		/*
806 		 * Devices can attach to two types of things: Attributes,
807 		 * and other devices (which have the appropriate attributes
808 		 * to allow attachment).
809 		 *
810 		 * (1) If we're attached to an attribute, then we don't need
811 		 *     look at the parent base device to see what attributes
812 		 *     it has, and make sure that we can attach to them.
813 		 *
814 		 * (2) If we're attached to a real device (i.e. named in
815 		 *     the config file), we want to remember that so that
816 		 *     at cross-check time, if the device we're attached to
817 		 *     is missing but other devices which also provide the
818 		 *     attribute are present, we don't get a false "OK."
819 		 *
820 		 * (3) If the thing we're attached to is an attribute
821 		 *     but is actually named in the config file, we still
822 		 *     have to remember its devbase.
823 		 */
824 
825 		/* Figure out parent's devbase, to satisfy case (3). */
826 		ab = ht_lookup(devbasetab, cp);
827 
828 		/* Find out if it's an attribute. */
829 		attr = ht_lookup(attrtab, cp);
830 
831 		/* Make sure we're _really_ attached to the attr.  Case (1). */
832 		if (attr != NULL && onlist(attr->a_devs, ib))
833 			goto findattachment;
834 
835 		/*
836 		 * Else a real device, and not just an attribute.  Case (2).
837 		 *
838 		 * Have to work a bit harder to see whether we have
839 		 * something like "tg0 at esp0" (where esp is merely
840 		 * not an attribute) or "tg0 at nonesuch0" (where
841 		 * nonesuch is not even a device).
842 		 */
843 		if (ab == NULL) {
844 			error("%s at %s: `%s' unknown",
845 			    name, at, atbuf);
846 			goto bad;
847 		}
848 
849 		/*
850 		 * See if the named parent carries an attribute
851 		 * that allows it to supervise device ib.
852 		 */
853 		for (nv = ab->d_attrs; nv != NULL; nv = nv->nv_next) {
854 			attr = nv->nv_ptr;
855 			if (onlist(attr->a_devs, ib))
856 				goto findattachment;
857 		}
858 		error("%s's cannot attach to %s's", ib->d_name, atbuf);
859 		goto bad;
860 
861 findattachment:
862 		/* find out which attachment it uses */
863 		hit = 0;
864 		for (iba = ib->d_ahead; iba != NULL; iba = iba->d_bsame)
865 			if (onlist(iba->d_atlist, attr)) {
866 				hit = 1;
867 				break;
868 			}
869 		if (!hit)
870 			panic("adddev: can't figure out attachment");
871 	}
872 	if ((i->i_locs = fixloc(name, attr, loclist)) == NULL)
873 		goto bad;
874 	i->i_at = at;
875 	i->i_atattr = attr;
876 	i->i_atdev = ab;
877 	i->i_atdeva = iba;
878 	i->i_atunit = atunit;
879 	i->i_cfflags = flags;
880 	i->i_disable = disable;
881 
882 	*iba->d_ipp = i;
883 	iba->d_ipp = &i->i_asame;
884 
885 	selectbase(ib, iba);
886 	/* all done, fall into ... */
887 bad:
888 	nvfreel(loclist);
889 	return;
890 }
891 
892 void
893 addpseudo(const char *name, int number, int disable)
894 {
895 	struct devbase *d;
896 	struct devi *i;
897 
898 	d = ht_lookup(devbasetab, name);
899 	if (d == NULL) {
900 		error("undefined pseudo-device %s", name);
901 		return;
902 	}
903 	if (!d->d_ispseudo) {
904 		error("%s is a real device, not a pseudo-device", name);
905 		return;
906 	}
907 	if (ht_lookup(devitab, name) != NULL) {
908 		warnx("warning: duplicate definition of `%s', will use latest definition", name);
909 		d->d_umax = number;
910 		return;
911 	}
912 	i = newdevi(name, number - 1, d);	/* foo 16 => "foo0..foo15" */
913 	if (ht_insert(devitab, name, i))
914 		panic("addpseudo(%s)", name);
915 	i->i_disable = disable;
916 	selectbase(d, NULL);
917 	*nextpseudo = i;
918 	nextpseudo = &i->i_next;
919 	npseudo++;
920 }
921 
922 /*
923  * Define a new instance of a specific device.
924  */
925 static struct devi *
926 getdevi(const char *name)
927 {
928 	struct devi *i, *firsti;
929 	struct devbase *d;
930 	int unit;
931 	char base[NAMESIZE];
932 
933 	if (split(name, strlen(name), base, sizeof base, &unit)) {
934 		error("invalid device name `%s'", name);
935 		return (NULL);
936 	}
937 	d = ht_lookup(devbasetab, intern(base));
938 	if (d == NULL) {
939 		error("%s: unknown device `%s'", name, base);
940 		return (NULL);
941 	}
942 	if (d->d_ispseudo) {
943 		error("%s: %s is a pseudo-device", name, base);
944 		return (NULL);
945 	}
946 	firsti = ht_lookup(devitab, name);
947 	i = newdevi(name, unit, d);
948 	if (firsti == NULL) {
949 		if (ht_insert(devitab, name, i))
950 			panic("getdevi(%s)", name);
951 		*d->d_ipp = i;
952 		d->d_ipp = &i->i_bsame;
953 	} else {
954 		while (firsti->i_alias)
955 			firsti = firsti->i_alias;
956 		firsti->i_alias = i;
957 	}
958 	*nextdevi = i;
959 	nextdevi = &i->i_next;
960 	ndevi++;
961 	return (i);
962 }
963 
964 static const char *
965 concat(const char *name, int c)
966 {
967 	size_t len;
968 	char buf[NAMESIZE];
969 
970 	len = strlen(name);
971 	if (len + 2 > sizeof(buf)) {
972 		error("device name `%s%c' too long", name, c);
973 		len = sizeof(buf) - 2;
974 	}
975 	bcopy(name, buf, len);
976 	buf[len] = c;
977 	buf[len + 1] = 0;
978 	return (intern(buf));
979 }
980 
981 const char *
982 starref(const char *name)
983 {
984 
985 	return (concat(name, '*'));
986 }
987 
988 const char *
989 wildref(const char *name)
990 {
991 
992 	return (concat(name, '?'));
993 }
994 
995 /*
996  * Split a name like "foo0" into base name (foo) and unit number (0).
997  * Return 0 on success.  To make this useful for names like "foo0a",
998  * the length of the "foo0" part is one of the arguments.
999  */
1000 static int
1001 split(const char *name, size_t nlen, char *base, size_t bsize, int *aunit)
1002 {
1003 	const char *cp;
1004 	int c;
1005 	size_t l;
1006 
1007 	l = nlen;
1008 	if (l < 2 || l >= bsize || isdigit((unsigned char)*name))
1009 		return (1);
1010 	c = (u_char)name[--l];
1011 	if (!isdigit((unsigned char)c)) {
1012 		if (c == '*')
1013 			*aunit = STAR;
1014 		else if (c == '?')
1015 			*aunit = WILD;
1016 		else
1017 			return (1);
1018 	} else {
1019 		cp = &name[l];
1020 		while (isdigit((unsigned char)cp[-1]))
1021 			l--, cp--;
1022 		*aunit = atoi(cp);
1023 	}
1024 	bcopy(name, base, l);
1025 	base[l] = 0;
1026 	return (0);
1027 }
1028 
1029 /*
1030  * We have an instance of the base foo, so select it and all its
1031  * attributes for "optional foo".
1032  */
1033 static void
1034 selectbase(struct devbase *d, struct deva *da)
1035 {
1036 	struct attr *a;
1037 	struct nvlist *nv;
1038 
1039 	(void)ht_insert(selecttab, d->d_name, (char *)d->d_name);
1040 	for (nv = d->d_attrs; nv != NULL; nv = nv->nv_next) {
1041 		a = nv->nv_ptr;
1042 		(void)ht_insert(selecttab, a->a_name, (char *)a->a_name);
1043 	}
1044 	if (da != NULL) {
1045 		(void)ht_insert(selecttab, da->d_name, (char *)da->d_name);
1046 		for (nv = da->d_attrs; nv != NULL; nv = nv->nv_next) {
1047 			a = nv->nv_ptr;
1048 			(void)ht_insert(selecttab, a->a_name,
1049 			    (char *)a->a_name);
1050 		}
1051 	}
1052 }
1053 
1054 /*
1055  * Is the given pointer on the given list of pointers?
1056  */
1057 static int
1058 onlist(struct nvlist *nv, void *ptr)
1059 {
1060 	for (; nv != NULL; nv = nv->nv_next)
1061 		if (nv->nv_ptr == ptr)
1062 			return (1);
1063 	return (0);
1064 }
1065 
1066 static char *
1067 extend(char *p, const char *name)
1068 {
1069 	int l;
1070 
1071 	l = strlen(name);
1072 	bcopy(name, p, l);
1073 	p += l;
1074 	*p++ = ',';
1075 	*p++ = ' ';
1076 	return (p);
1077 }
1078 
1079 /*
1080  * Check that we got all required locators, and default any that are
1081  * given as "?" and have defaults.  Return 0 on success.
1082  */
1083 static const char **
1084 fixloc(const char *name, struct attr *attr, struct nvlist *got)
1085 {
1086 	struct nvlist *m, *n;
1087 	int ord;
1088 	const char **lp;
1089 	int nmissing, nextra, nnodefault;
1090 	char *mp, *ep, *ndp;
1091 	char missing[1000], extra[1000], nodefault[1000];
1092 	static const char *nullvec[1];
1093 
1094 	/*
1095 	 * Look for all required locators, and number the given ones
1096 	 * according to the required order.  While we are numbering,
1097 	 * set default values for defaulted locators.
1098 	 */
1099 	if (attr->a_loclen == 0)	/* e.g., "at root" */
1100 		lp = nullvec;
1101 	else
1102 		lp = ereallocarray(NULL, attr->a_loclen + 1,
1103 		    sizeof(const char *));
1104 	for (n = got; n != NULL; n = n->nv_next)
1105 		n->nv_int = -1;
1106 	nmissing = 0;
1107 	mp = missing;
1108 	/* yes, this is O(mn), but m and n should be small */
1109 	for (ord = 0, m = attr->a_locs; m != NULL; m = m->nv_next, ord++) {
1110 		for (n = got; n != NULL; n = n->nv_next) {
1111 			if (n->nv_name == m->nv_name) {
1112 				n->nv_int = ord;
1113 				break;
1114 			}
1115 		}
1116 		if (n == NULL && m->nv_int == 0) {
1117 			nmissing++;
1118 			mp = extend(mp, m->nv_name);
1119 		}
1120 		lp[ord] = m->nv_str;
1121 	}
1122 	if (ord != attr->a_loclen)
1123 		panic("fixloc");
1124 	lp[ord] = NULL;
1125 	nextra = 0;
1126 	ep = extra;
1127 	nnodefault = 0;
1128 	ndp = nodefault;
1129 	for (n = got; n != NULL; n = n->nv_next) {
1130 		if (n->nv_int >= 0) {
1131 			if (n->nv_str != NULL)
1132 				lp[n->nv_int] = n->nv_str;
1133 			else if (lp[n->nv_int] == NULL) {
1134 				nnodefault++;
1135 				ndp = extend(ndp, n->nv_name);
1136 			}
1137 		} else {
1138 			nextra++;
1139 			ep = extend(ep, n->nv_name);
1140 		}
1141 	}
1142 	if (nextra) {
1143 		ep[-2] = 0;	/* kill ", " */
1144 		error("%s: extraneous locator%s: %s",
1145 		    name, nextra > 1 ? "s" : "", extra);
1146 	}
1147 	if (nmissing) {
1148 		mp[-2] = 0;
1149 		error("%s: must specify %s", name, missing);
1150 	}
1151 	if (nnodefault) {
1152 		ndp[-2] = 0;
1153 		error("%s: cannot wildcard %s", name, nodefault);
1154 	}
1155 	if (nmissing || nnodefault) {
1156 		free(lp);
1157 		lp = NULL;
1158 	}
1159 	return (lp);
1160 }
1161