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sem.c revision 1.52
      1 /*	$NetBSD: sem.c,v 1.52 2014/10/10 07:48:50 uebayasi Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1992, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * This software was developed by the Computer Systems Engineering group
      8  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
      9  * contributed to Berkeley.
     10  *
     11  * All advertising materials mentioning features or use of this software
     12  * must display the following acknowledgement:
     13  *	This product includes software developed by the University of
     14  *	California, Lawrence Berkeley Laboratories.
     15  *
     16  * Redistribution and use in source and binary forms, with or without
     17  * modification, are permitted provided that the following conditions
     18  * are met:
     19  * 1. Redistributions of source code must retain the above copyright
     20  *    notice, this list of conditions and the following disclaimer.
     21  * 2. Redistributions in binary form must reproduce the above copyright
     22  *    notice, this list of conditions and the following disclaimer in the
     23  *    documentation and/or other materials provided with the distribution.
     24  * 3. Neither the name of the University nor the names of its contributors
     25  *    may be used to endorse or promote products derived from this software
     26  *    without specific prior written permission.
     27  *
     28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     38  * SUCH DAMAGE.
     39  *
     40  *	from: @(#)sem.c	8.1 (Berkeley) 6/6/93
     41  */
     42 
     43 #if HAVE_NBTOOL_CONFIG_H
     44 #include "nbtool_config.h"
     45 #endif
     46 
     47 #include <sys/param.h>
     48 #include <ctype.h>
     49 #include <stdio.h>
     50 #include <stdlib.h>
     51 #include <string.h>
     52 #include <util.h>
     53 #include "defs.h"
     54 #include "sem.h"
     55 
     56 /*
     57  * config semantics.
     58  */
     59 
     60 #define	NAMESIZE	100	/* local name buffers */
     61 
     62 const char *s_ifnet;		/* magic attribute */
     63 const char *s_qmark;
     64 const char *s_none;
     65 
     66 static struct hashtab *cfhashtab;	/* for config lookup */
     67 struct hashtab *devitab;		/* etc */
     68 struct attr allattr;
     69 
     70 static struct attr errattr;
     71 static struct devbase errdev;
     72 static struct deva errdeva;
     73 
     74 static int has_errobj(struct attrlist *, struct attr *);
     75 static struct nvlist *addtoattr(struct nvlist *, struct devbase *);
     76 static int resolve(struct nvlist **, const char *, const char *,
     77 		   struct nvlist *, int);
     78 static struct pspec *getpspec(struct attr *, struct devbase *, int);
     79 static struct devi *newdevi(const char *, int, struct devbase *d);
     80 static struct devi *getdevi(const char *);
     81 static void remove_devi(struct devi *);
     82 static const char *concat(const char *, int);
     83 static char *extend(char *, const char *);
     84 static int split(const char *, size_t, char *, size_t, int *);
     85 static void selectbase(struct devbase *, struct deva *);
     86 static const char **fixloc(const char *, struct attr *, struct loclist *);
     87 static const char *makedevstr(devmajor_t, devminor_t);
     88 static const char *major2name(devmajor_t);
     89 static devmajor_t dev2major(struct devbase *);
     90 
     91 extern const char *yyfile;
     92 extern int vflag;
     93 
     94 void
     95 initsem(void)
     96 {
     97 
     98 	attrtab = ht_new();
     99 
    100 	allattr.a_name = "netbsd";
    101 	TAILQ_INIT(&allattr.a_files);
    102 	(void)ht_insert(attrtab, allattr.a_name, &allattr);
    103 	selectattr(&allattr);
    104 
    105 	errattr.a_name = "<internal>";
    106 
    107 	TAILQ_INIT(&allbases);
    108 
    109 	TAILQ_INIT(&alldevas);
    110 
    111 	TAILQ_INIT(&allpspecs);
    112 
    113 	cfhashtab = ht_new();
    114 	TAILQ_INIT(&allcf);
    115 
    116 	TAILQ_INIT(&alldevi);
    117 	errdev.d_name = "<internal>";
    118 
    119 	TAILQ_INIT(&allpseudo);
    120 
    121 	TAILQ_INIT(&alldevms);
    122 
    123 	s_ifnet = intern("ifnet");
    124 	s_qmark = intern("?");
    125 	s_none = intern("none");
    126 }
    127 
    128 /* Name of include file just ended (set in scan.l) */
    129 extern const char *lastfile;
    130 
    131 void
    132 enddefs(void)
    133 {
    134 	struct devbase *dev;
    135 
    136 	TAILQ_FOREACH(dev, &allbases, d_next) {
    137 		if (!dev->d_isdef) {
    138 			(void)fprintf(stderr,
    139 			    "%s: device `%s' used but not defined\n",
    140 			    lastfile, dev->d_name);
    141 			errors++;
    142 			continue;
    143 		}
    144 	}
    145 	if (errors) {
    146 		(void)fprintf(stderr, "*** Stop.\n");
    147 		exit(1);
    148 	}
    149 }
    150 
    151 void
    152 setdefmaxusers(int min, int def, int max)
    153 {
    154 
    155 	if (min < 1 || min > def || def > max)
    156 		cfgerror("maxusers must have 1 <= min (%d) <= default (%d) "
    157 		    "<= max (%d)", min, def, max);
    158 	else {
    159 		minmaxusers = min;
    160 		defmaxusers = def;
    161 		maxmaxusers = max;
    162 	}
    163 }
    164 
    165 void
    166 setmaxusers(int n)
    167 {
    168 
    169 	if (maxusers == n) {
    170 		cfgerror("duplicate maxusers parameter");
    171 		return;
    172 	}
    173 	if (vflag && maxusers != 0)
    174 		cfgwarn("warning: maxusers already defined");
    175 	maxusers = n;
    176 	if (n < minmaxusers) {
    177 		cfgerror("warning: minimum of %d maxusers assumed",
    178 		    minmaxusers);
    179 		errors--;	/* take it away */
    180 		maxusers = minmaxusers;
    181 	} else if (n > maxmaxusers) {
    182 		cfgerror("warning: maxusers (%d) > %d", n, maxmaxusers);
    183 		errors--;
    184 	}
    185 }
    186 
    187 void
    188 setident(const char *i)
    189 {
    190 
    191 	if (i)
    192 		ident = intern(i);
    193 	else
    194 		ident = NULL;
    195 }
    196 
    197 /*
    198  * Define an attribute, optionally with an interface (a locator list)
    199  * and a set of attribute-dependencies.
    200  *
    201  * Attribute dependencies MAY NOT be interface attributes.
    202  *
    203  * Since an empty locator list is logically different from "no interface",
    204  * all locator lists include a dummy head node, which we discard here.
    205  */
    206 int
    207 defattr0(const char *name, struct loclist *locs, struct attrlist *deps,
    208     int devclass)
    209 {
    210 
    211 	if (locs != NULL)
    212 		return defiattr(name, locs, deps, devclass);
    213 	else if (devclass)
    214 		return defdevclass(name, locs, deps, devclass);
    215 	else
    216 		return defattr(name, locs, deps, devclass);
    217 }
    218 
    219 int
    220 defattr(const char *name, struct loclist *locs, struct attrlist *deps,
    221     int devclass)
    222 {
    223 	struct attr *a, *dep;
    224 	struct attrlist *al;
    225 
    226 	/*
    227 	 * If this attribute depends on any others, make sure none of
    228 	 * the dependencies are interface attributes.
    229 	 */
    230 	for (al = deps; al != NULL; al = al->al_next) {
    231 		dep = al->al_this;
    232 		if (dep->a_iattr) {
    233 			cfgerror("`%s' dependency `%s' is an interface "
    234 			    "attribute", name, dep->a_name);
    235 			return (1);
    236 		}
    237 	}
    238 
    239 	if (getrefattr(name, &a)) {
    240 		cfgerror("attribute `%s' already defined", name);
    241 		loclist_destroy(locs);
    242 		return (1);
    243 	}
    244 	if (a == NULL)
    245 		a = mkattr(name);
    246 
    247 	a->a_deps = deps;
    248 	expandattr(a, NULL);
    249 	CFGDBG(3, "attr `%s' defined", a->a_name);
    250 
    251 	return (0);
    252 }
    253 
    254 struct attr *
    255 mkattr(const char *name)
    256 {
    257 	struct attr *a;
    258 
    259 	a = ecalloc(1, sizeof *a);
    260 	if (ht_insert(attrtab, name, a)) {
    261 		free(a);
    262 		return NULL;
    263 	}
    264 	a->a_name = name;
    265 	TAILQ_INIT(&a->a_files);
    266 	CFGDBG(3, "attr `%s' allocated", name);
    267 
    268 	return a;
    269 }
    270 
    271 /* "interface attribute" initialization */
    272 int
    273 defiattr(const char *name, struct loclist *locs, struct attrlist *deps,
    274     int devclass)
    275 {
    276 	struct attr *a;
    277 	int len;
    278 	struct loclist *ll;
    279 
    280 	if (devclass)
    281 		panic("defattr(%s): locators and devclass", name);
    282 
    283 	if (defattr(name, locs, deps, devclass) != 0)
    284 		return (1);
    285 
    286 	a = getattr(name);
    287 	a->a_iattr = 1;
    288 	/* unwrap */
    289 	a->a_locs = locs->ll_next;
    290 	locs->ll_next = NULL;
    291 	loclist_destroy(locs);
    292 	len = 0;
    293 	for (ll = a->a_locs; ll != NULL; ll = ll->ll_next)
    294 		len++;
    295 	a->a_loclen = len;
    296 	if (deps)
    297 		CFGDBG(2, "attr `%s' iface with deps", a->a_name);
    298 	return (0);
    299 }
    300 
    301 /* "device class" initialization */
    302 int
    303 defdevclass(const char *name, struct loclist *locs, struct attrlist *deps,
    304     int devclass)
    305 {
    306 	struct attr *a;
    307 	char classenum[256], *cp;
    308 	int errored = 0;
    309 
    310 	if (deps)
    311 		panic("defattr(%s): dependencies and devclass", name);
    312 
    313 	if (defattr(name, locs, deps, devclass) != 0)
    314 		return (1);
    315 
    316 	a = getattr(name);
    317 	(void)snprintf(classenum, sizeof(classenum), "DV_%s", name);
    318 	for (cp = classenum + 3; *cp; cp++) {
    319 		if (!errored &&
    320 		    (!isalnum((unsigned char)*cp) ||
    321 		      (isalpha((unsigned char)*cp) && !islower((unsigned char)*cp)))) {
    322 			cfgerror("device class names must be "
    323 			    "lower-case alphanumeric characters");
    324 			errored = 1;
    325 		}
    326 		*cp = toupper((unsigned char)*cp);
    327 	}
    328 	a->a_devclass = intern(classenum);
    329 
    330 	return (0);
    331 }
    332 
    333 /*
    334  * Return true if the given `error object' is embedded in the given
    335  * pointer list.
    336  */
    337 static int
    338 has_errobj(struct attrlist *al, struct attr *obj)
    339 {
    340 
    341 	for (; al != NULL; al = al->al_next)
    342 		if (al->al_this == obj)
    343 			return (1);
    344 	return (0);
    345 }
    346 
    347 /*
    348  * Return true if the given attribute is embedded in the given
    349  * pointer list.
    350  */
    351 int
    352 has_attr(struct attrlist *al, const char *attr)
    353 {
    354 	struct attr *a;
    355 
    356 	if ((a = getattr(attr)) == NULL)
    357 		return (0);
    358 
    359 	for (; al != NULL; al = al->al_next)
    360 		if (al->al_this == a)
    361 			return (1);
    362 	return (0);
    363 }
    364 
    365 /*
    366  * Add a device base to a list in an attribute (actually, to any list).
    367  * Note that this does not check for duplicates, and does reverse the
    368  * list order, but no one cares anyway.
    369  */
    370 static struct nvlist *
    371 addtoattr(struct nvlist *l, struct devbase *dev)
    372 {
    373 	struct nvlist *n;
    374 
    375 	n = newnv(NULL, NULL, dev, 0, l);
    376 	return (n);
    377 }
    378 
    379 /*
    380  * Define a device.  This may (or may not) also define an interface
    381  * attribute and/or refer to existing attributes.
    382  */
    383 void
    384 defdev(struct devbase *dev, struct loclist *loclist, struct attrlist *attrs,
    385        int ispseudo)
    386 {
    387 	struct loclist *ll;
    388 	struct attrlist *al;
    389 	struct attr *a;
    390 
    391 	if (dev == &errdev)
    392 		goto bad;
    393 	if (dev->d_isdef) {
    394 		cfgerror("redefinition of `%s'", dev->d_name);
    395 		goto bad;
    396 	}
    397 
    398 	dev->d_isdef = 1;
    399 	if (has_errobj(attrs, &errattr))
    400 		goto bad;
    401 
    402 	/*
    403 	 * Handle implicit attribute definition from locator list.  Do
    404 	 * this before scanning the `at' list so that we can have, e.g.:
    405 	 *	device foo at other, foo { slot = -1 }
    406 	 * (where you can plug in a foo-bus extender to a foo-bus).
    407 	 */
    408 	if (loclist != NULL) {
    409 		ll = loclist;
    410 		loclist = NULL;	/* defattr disposes of them for us */
    411 		if (defiattr(dev->d_name, ll, NULL, 0))
    412 			goto bad;
    413 		attrs = attrlist_cons(attrs, getattr(dev->d_name));
    414 		/* This used to be stored but was never used */
    415 		/* attrs->al_name = dev->d_name; */
    416 	}
    417 
    418 	/*
    419 	 * Pseudo-devices can have children.  Consider them as
    420 	 * attaching at root.
    421 	 */
    422 	if (ispseudo) {
    423 		for (al = attrs; al != NULL; al = al->al_next)
    424 			if (al->al_this->a_iattr)
    425 				break;
    426 		if (al != NULL) {
    427 			if (ispseudo < 2) {
    428 				if (version >= 20080610)
    429 					cfgerror("interface attribute on "
    430 					 "non-device pseudo `%s'", dev->d_name);
    431 				else {
    432 					ispseudo = 2;
    433 				}
    434 			}
    435 			ht_insert(devroottab, dev->d_name, dev);
    436 		}
    437 	}
    438 
    439 	/* Committed!  Set up fields. */
    440 	dev->d_ispseudo = ispseudo;
    441 	dev->d_attrs = attrs;
    442 	dev->d_classattr = NULL;		/* for now */
    443 
    444 	/*
    445 	 * For each interface attribute this device refers to, add this
    446 	 * device to its reference list.  This makes, e.g., finding all
    447 	 * "scsi"s easier.
    448 	 *
    449 	 * While looking through the attributes, set up the device
    450 	 * class if any are devclass attributes (and error out if the
    451 	 * device has two classes).
    452 	 */
    453 	for (al = attrs; al != NULL; al = al->al_next) {
    454 		a = al->al_this;
    455 		if (a->a_iattr)
    456 			a->a_refs = addtoattr(a->a_refs, dev);
    457 		if (a->a_devclass != NULL) {
    458 			if (dev->d_classattr != NULL) {
    459 				cfgerror("device `%s' has multiple classes "
    460 				    "(`%s' and `%s')",
    461 				    dev->d_name, dev->d_classattr->a_name,
    462 				    a->a_name);
    463 			}
    464 			dev->d_classattr = a;
    465 		}
    466 	}
    467 	return;
    468  bad:
    469 	loclist_destroy(loclist);
    470 	attrlist_destroyall(attrs);
    471 }
    472 
    473 /*
    474  * Look up a devbase.  Also makes sure it is a reasonable name,
    475  * i.e., does not end in a digit or contain special characters.
    476  */
    477 struct devbase *
    478 getdevbase(const char *name)
    479 {
    480 	const u_char *p;
    481 	struct devbase *dev;
    482 
    483 	p = (const u_char *)name;
    484 	if (!isalpha(*p))
    485 		goto badname;
    486 	while (*++p) {
    487 		if (!isalnum(*p) && *p != '_')
    488 			goto badname;
    489 	}
    490 	if (isdigit(*--p)) {
    491  badname:
    492 		cfgerror("bad device base name `%s'", name);
    493 		return (&errdev);
    494 	}
    495 	dev = ht_lookup(devbasetab, name);
    496 	if (dev == NULL) {
    497 		dev = ecalloc(1, sizeof *dev);
    498 		dev->d_name = name;
    499 		dev->d_isdef = 0;
    500 		dev->d_major = NODEVMAJOR;
    501 		dev->d_attrs = NULL;
    502 		dev->d_ihead = NULL;
    503 		dev->d_ipp = &dev->d_ihead;
    504 		dev->d_ahead = NULL;
    505 		dev->d_app = &dev->d_ahead;
    506 		dev->d_umax = 0;
    507 		TAILQ_INSERT_TAIL(&allbases, dev, d_next);
    508 		if (ht_insert(devbasetab, name, dev))
    509 			panic("getdevbase(%s)", name);
    510 	}
    511 	return (dev);
    512 }
    513 
    514 /*
    515  * Define some of a device's allowable parent attachments.
    516  * There may be a list of (plain) attributes.
    517  */
    518 void
    519 defdevattach(struct deva *deva, struct devbase *dev, struct nvlist *atlist,
    520 	     struct attrlist *attrs)
    521 {
    522 	struct nvlist *nv;
    523 	struct attrlist *al;
    524 	struct attr *a;
    525 	struct deva *da;
    526 
    527 	if (dev == &errdev)
    528 		goto bad;
    529 	if (deva == NULL)
    530 		deva = getdevattach(dev->d_name);
    531 	if (deva == &errdeva)
    532 		goto bad;
    533 	if (!dev->d_isdef) {
    534 		cfgerror("attaching undefined device `%s'", dev->d_name);
    535 		goto bad;
    536 	}
    537 	if (deva->d_isdef) {
    538 		cfgerror("redefinition of `%s'", deva->d_name);
    539 		goto bad;
    540 	}
    541 	if (dev->d_ispseudo) {
    542 		cfgerror("pseudo-devices can't attach");
    543 		goto bad;
    544 	}
    545 
    546 	deva->d_isdef = 1;
    547 	if (has_errobj(attrs, &errattr))
    548 		goto bad;
    549 	for (al = attrs; al != NULL; al = al->al_next) {
    550 		a = al->al_this;
    551 		if (a == &errattr)
    552 			continue;		/* already complained */
    553 		if (a->a_iattr || a->a_devclass != NULL)
    554 			cfgerror("`%s' is not a plain attribute", a->a_name);
    555 	}
    556 
    557 	/* Committed!  Set up fields. */
    558 	deva->d_attrs = attrs;
    559 	deva->d_atlist = atlist;
    560 	deva->d_devbase = dev;
    561 	CFGDBG(3, "deva `%s' defined", deva->d_name);
    562 
    563 	/*
    564 	 * Implicit attribute definition for device attachment.
    565 	 */
    566 	refattr(deva->d_name);
    567 
    568 	/*
    569 	 * Turn the `at' list into interface attributes (map each
    570 	 * nv_name to an attribute, or to NULL for root), and add
    571 	 * this device to those attributes, so that children can
    572 	 * be listed at this particular device if they are supported
    573 	 * by that attribute.
    574 	 */
    575 	for (nv = atlist; nv != NULL; nv = nv->nv_next) {
    576 		if (nv->nv_name == NULL)
    577 			nv->nv_ptr = a = NULL;	/* at root */
    578 		else
    579 			nv->nv_ptr = a = getattr(nv->nv_name);
    580 		if (a == &errattr)
    581 			continue;		/* already complained */
    582 
    583 		/*
    584 		 * Make sure that an attachment spec doesn't
    585 		 * already say how to attach to this attribute.
    586 		 */
    587 		for (da = dev->d_ahead; da != NULL; da = da->d_bsame)
    588 			if (onlist(da->d_atlist, a))
    589 				cfgerror("attach at `%s' already done by `%s'",
    590 				     a ? a->a_name : "root", da->d_name);
    591 
    592 		if (a == NULL) {
    593 			ht_insert(devroottab, dev->d_name, dev);
    594 			continue;		/* at root; don't add */
    595 		}
    596 		if (!a->a_iattr)
    597 			cfgerror("%s cannot be at plain attribute `%s'",
    598 			    dev->d_name, a->a_name);
    599 		else
    600 			a->a_devs = addtoattr(a->a_devs, dev);
    601 	}
    602 
    603 	/* attach to parent */
    604 	*dev->d_app = deva;
    605 	dev->d_app = &deva->d_bsame;
    606 	return;
    607  bad:
    608 	nvfreel(atlist);
    609 	attrlist_destroyall(attrs);
    610 }
    611 
    612 /*
    613  * Look up a device attachment.  Also makes sure it is a reasonable
    614  * name, i.e., does not contain digits or special characters.
    615  */
    616 struct deva *
    617 getdevattach(const char *name)
    618 {
    619 	const u_char *p;
    620 	struct deva *deva;
    621 
    622 	p = (const u_char *)name;
    623 	if (!isalpha(*p))
    624 		goto badname;
    625 	while (*++p) {
    626 		if (!isalnum(*p) && *p != '_')
    627 			goto badname;
    628 	}
    629 	if (isdigit(*--p)) {
    630  badname:
    631 		cfgerror("bad device attachment name `%s'", name);
    632 		return (&errdeva);
    633 	}
    634 	deva = ht_lookup(devatab, name);
    635 	if (deva == NULL) {
    636 		deva = ecalloc(1, sizeof *deva);
    637 		deva->d_name = name;
    638 		deva->d_bsame = NULL;
    639 		deva->d_isdef = 0;
    640 		deva->d_devbase = NULL;
    641 		deva->d_atlist = NULL;
    642 		deva->d_attrs = NULL;
    643 		deva->d_ihead = NULL;
    644 		deva->d_ipp = &deva->d_ihead;
    645 		TAILQ_INSERT_TAIL(&alldevas, deva, d_next);
    646 		if (ht_insert(devatab, name, deva))
    647 			panic("getdeva(%s)", name);
    648 	}
    649 	return (deva);
    650 }
    651 
    652 /*
    653  * Look up an attribute.
    654  */
    655 struct attr *
    656 getattr(const char *name)
    657 {
    658 	struct attr *a;
    659 
    660 	if ((a = ht_lookup(attrtab, name)) == NULL) {
    661 		cfgerror("undefined attribute `%s'", name);
    662 		a = &errattr;
    663 	}
    664 	return (a);
    665 }
    666 
    667 /*
    668  * Implicit attribute definition.
    669  */
    670 void
    671 refattr(const char *name)
    672 {
    673 
    674 	if ((ht_lookup(attrtab, name)) == NULL)
    675 		(void)mkattr(name);
    676 }
    677 
    678 int
    679 getrefattr(const char *name, struct attr **ra)
    680 {
    681 	struct attr *a;
    682 
    683 	a = ht_lookup(attrtab, name);
    684 	if (a == NULL) {
    685 		*ra = NULL;
    686 		return (0);
    687 	}
    688 	/*
    689 	 * Check if the existing attr is only referenced, not really defined.
    690 	 */
    691 	if (a->a_deps == NULL &&
    692 	    a->a_iattr == 0 &&
    693 	    a->a_devclass == 0) {
    694 		*ra = a;
    695 		return (0);
    696 	}
    697 	return (1);
    698 }
    699 
    700 /*
    701  * Recursively expand an attribute and its dependencies, checking for
    702  * cycles, and invoking a callback for each attribute found.
    703  */
    704 void
    705 expandattr(struct attr *a, void (*callback)(struct attr *))
    706 {
    707 	struct attrlist *al;
    708 	struct attr *dep;
    709 
    710 	if (a->a_expanding) {
    711 		cfgerror("circular dependency on attribute `%s'", a->a_name);
    712 		return;
    713 	}
    714 
    715 	a->a_expanding = 1;
    716 
    717 	/* First expand all of this attribute's dependencies. */
    718 	for (al = a->a_deps; al != NULL; al = al->al_next) {
    719 		dep = al->al_this;
    720 		expandattr(dep, callback);
    721 	}
    722 
    723 	/* ...and now invoke the callback for ourself. */
    724 	if (callback != NULL)
    725 		(*callback)(a);
    726 
    727 	a->a_expanding = 0;
    728 }
    729 
    730 /*
    731  * Set the major device number for a device, so that it can be used
    732  * as a root/dumps "on" device in a configuration.
    733  */
    734 void
    735 setmajor(struct devbase *d, devmajor_t n)
    736 {
    737 
    738 	if (d != &errdev && d->d_major != NODEVMAJOR)
    739 		cfgerror("device `%s' is already major %d",
    740 		    d->d_name, d->d_major);
    741 	else
    742 		d->d_major = n;
    743 }
    744 
    745 const char *
    746 major2name(devmajor_t maj)
    747 {
    748 	struct devbase *dev;
    749 	struct devm *dm;
    750 
    751 	if (!do_devsw) {
    752 		TAILQ_FOREACH(dev, &allbases, d_next) {
    753 			if (dev->d_major == maj)
    754 				return (dev->d_name);
    755 		}
    756 	} else {
    757 		TAILQ_FOREACH(dm, &alldevms, dm_next) {
    758 			if (dm->dm_bmajor == maj)
    759 				return (dm->dm_name);
    760 		}
    761 	}
    762 	return (NULL);
    763 }
    764 
    765 devmajor_t
    766 dev2major(struct devbase *dev)
    767 {
    768 	struct devm *dm;
    769 
    770 	if (!do_devsw)
    771 		return (dev->d_major);
    772 
    773 	TAILQ_FOREACH(dm, &alldevms, dm_next) {
    774 		if (strcmp(dm->dm_name, dev->d_name) == 0)
    775 			return (dm->dm_bmajor);
    776 	}
    777 	return (NODEVMAJOR);
    778 }
    779 
    780 /*
    781  * Make a string description of the device at maj/min.
    782  */
    783 static const char *
    784 makedevstr(devmajor_t maj, devminor_t min)
    785 {
    786 	const char *devicename;
    787 	char buf[32];
    788 
    789 	devicename = major2name(maj);
    790 	if (devicename == NULL)
    791 		(void)snprintf(buf, sizeof(buf), "<%d/%d>", maj, min);
    792 	else
    793 		(void)snprintf(buf, sizeof(buf), "%s%d%c", devicename,
    794 		    min / maxpartitions, (min % maxpartitions) + 'a');
    795 
    796 	return (intern(buf));
    797 }
    798 
    799 /*
    800  * Map things like "ra0b" => makedev(major("ra"), 0*maxpartitions + 'b'-'a').
    801  * Handle the case where the device number is given but there is no
    802  * corresponding name, and map NULL to the default.
    803  */
    804 static int
    805 resolve(struct nvlist **nvp, const char *name, const char *what,
    806 	struct nvlist *dflt, int part)
    807 {
    808 	struct nvlist *nv;
    809 	struct devbase *dev;
    810 	const char *cp;
    811 	devmajor_t maj;
    812 	devminor_t min;
    813 	int i, l;
    814 	int unit;
    815 	char buf[NAMESIZE];
    816 
    817 	if ((part -= 'a') >= maxpartitions || part < 0)
    818 		panic("resolve");
    819 	if ((nv = *nvp) == NULL) {
    820 		dev_t	d = NODEV;
    821 		/*
    822 		 * Apply default.  Easiest to do this by number.
    823 		 * Make sure to retain NODEVness, if this is dflt's disposition.
    824 		 */
    825 		if ((dev_t)dflt->nv_num != NODEV) {
    826 			maj = major(dflt->nv_num);
    827 			min = ((minor(dflt->nv_num) / maxpartitions) *
    828 			    maxpartitions) + part;
    829 			d = makedev(maj, min);
    830 			cp = makedevstr(maj, min);
    831 		} else
    832 			cp = NULL;
    833 		*nvp = nv = newnv(NULL, cp, NULL, d, NULL);
    834 	}
    835 	if ((dev_t)nv->nv_num != NODEV) {
    836 		/*
    837 		 * By the numbers.  Find the appropriate major number
    838 		 * to make a name.
    839 		 */
    840 		maj = major(nv->nv_num);
    841 		min = minor(nv->nv_num);
    842 		nv->nv_str = makedevstr(maj, min);
    843 		return (0);
    844 	}
    845 
    846 	if (nv->nv_str == NULL || nv->nv_str == s_qmark)
    847 		/*
    848 		 * Wildcarded or unspecified; leave it as NODEV.
    849 		 */
    850 		return (0);
    851 
    852 	/*
    853 	 * The normal case: things like "ra2b".  Check for partition
    854 	 * suffix, remove it if there, and split into name ("ra") and
    855 	 * unit (2).
    856 	 */
    857 	l = i = strlen(nv->nv_str);
    858 	cp = &nv->nv_str[l];
    859 	if (l > 1 && *--cp >= 'a' && *cp < 'a' + maxpartitions &&
    860 	    isdigit((unsigned char)cp[-1])) {
    861 		l--;
    862 		part = *cp - 'a';
    863 	}
    864 	cp = nv->nv_str;
    865 	if (split(cp, l, buf, sizeof buf, &unit)) {
    866 		cfgerror("%s: invalid %s device name `%s'", name, what, cp);
    867 		return (1);
    868 	}
    869 	dev = ht_lookup(devbasetab, intern(buf));
    870 	if (dev == NULL) {
    871 		cfgerror("%s: device `%s' does not exist", name, buf);
    872 		return (1);
    873 	}
    874 
    875 	/*
    876 	 * Check for the magic network interface attribute, and
    877 	 * don't bother making a device number.
    878 	 */
    879 	if (has_attr(dev->d_attrs, s_ifnet)) {
    880 		nv->nv_num = NODEV;
    881 		nv->nv_ifunit = unit;	/* XXX XXX XXX */
    882 	} else {
    883 		maj = dev2major(dev);
    884 		if (maj == NODEVMAJOR) {
    885 			cfgerror("%s: can't make %s device from `%s'",
    886 			    name, what, nv->nv_str);
    887 			return (1);
    888 		}
    889 		nv->nv_num = makedev(maj, unit * maxpartitions + part);
    890 	}
    891 
    892 	nv->nv_name = dev->d_name;
    893 	return (0);
    894 }
    895 
    896 /*
    897  * Add a completed configuration to the list.
    898  */
    899 void
    900 addconf(struct config *cf0)
    901 {
    902 	struct config *cf;
    903 	const char *name;
    904 
    905 	name = cf0->cf_name;
    906 	cf = ecalloc(1, sizeof *cf);
    907 	if (ht_insert(cfhashtab, name, cf)) {
    908 		cfgerror("configuration `%s' already defined", name);
    909 		free(cf);
    910 		goto bad;
    911 	}
    912 	*cf = *cf0;
    913 
    914 	/*
    915 	 * Resolve the root device.
    916 	 */
    917 	if (cf->cf_root == NULL) {
    918 		cfgerror("%s: no root device specified", name);
    919 		goto bad;
    920 	}
    921 	if (cf->cf_root && cf->cf_root->nv_str != s_qmark) {
    922 		struct nvlist *nv;
    923 		nv = cf->cf_root;
    924 		if (resolve(&cf->cf_root, name, "root", nv, 'a'))
    925 			goto bad;
    926 	}
    927 
    928 	/*
    929 	 * Resolve the dump device.
    930 	 */
    931 	if (cf->cf_dump == NULL || cf->cf_dump->nv_str == s_qmark) {
    932 		/*
    933 		 * Wildcarded dump device is equivalent to unspecified.
    934 		 */
    935 		cf->cf_dump = NULL;
    936 	} else if (cf->cf_dump->nv_str == s_none) {
    937 		/*
    938 		 * Operator has requested that no dump device should be
    939 		 * configured; do nothing.
    940 		 */
    941 	} else {
    942 		if (resolve(&cf->cf_dump, name, "dumps", cf->cf_dump, 'b'))
    943 			goto bad;
    944 	}
    945 
    946 	/* Wildcarded fstype is `unspecified'. */
    947 	if (cf->cf_fstype == s_qmark)
    948 		cf->cf_fstype = NULL;
    949 
    950 	TAILQ_INSERT_TAIL(&allcf, cf, cf_next);
    951 	return;
    952  bad:
    953 	nvfreel(cf0->cf_root);
    954 	nvfreel(cf0->cf_dump);
    955 }
    956 
    957 void
    958 setconf(struct nvlist **npp, const char *what, struct nvlist *v)
    959 {
    960 
    961 	if (*npp != NULL) {
    962 		cfgerror("duplicate %s specification", what);
    963 		nvfreel(v);
    964 	} else
    965 		*npp = v;
    966 }
    967 
    968 void
    969 delconf(const char *name)
    970 {
    971 	struct config *cf;
    972 
    973 	if (ht_lookup(cfhashtab, name) == NULL) {
    974 		cfgerror("configuration `%s' undefined", name);
    975 		return;
    976 	}
    977 	(void)ht_remove(cfhashtab, name);
    978 
    979 	TAILQ_FOREACH(cf, &allcf, cf_next)
    980 		if (!strcmp(cf->cf_name, name))
    981 			break;
    982 	if (cf == NULL)
    983 		panic("lost configuration `%s'", name);
    984 
    985 	TAILQ_REMOVE(&allcf, cf, cf_next);
    986 }
    987 
    988 void
    989 setfstype(const char **fstp, const char *v)
    990 {
    991 
    992 	if (*fstp != NULL) {
    993 		cfgerror("multiple fstype specifications");
    994 		return;
    995 	}
    996 
    997 	if (v != s_qmark && OPT_FSOPT(v)) {
    998 		cfgerror("\"%s\" is not a configured file system", v);
    999 		return;
   1000 	}
   1001 
   1002 	*fstp = v;
   1003 }
   1004 
   1005 static struct devi *
   1006 newdevi(const char *name, int unit, struct devbase *d)
   1007 {
   1008 	struct devi *i;
   1009 
   1010 	i = ecalloc(1, sizeof *i);
   1011 	i->i_name = name;
   1012 	i->i_unit = unit;
   1013 	i->i_base = d;
   1014 	i->i_bsame = NULL;
   1015 	i->i_asame = NULL;
   1016 	i->i_alias = NULL;
   1017 	i->i_at = NULL;
   1018 	i->i_pspec = NULL;
   1019 	i->i_atdeva = NULL;
   1020 	i->i_locs = NULL;
   1021 	i->i_cfflags = 0;
   1022 	i->i_lineno = currentline();
   1023 	i->i_srcfile = yyfile;
   1024 	i->i_active = DEVI_ORPHAN; /* Proper analysis comes later */
   1025 	i->i_level = devilevel;
   1026 	i->i_pseudoroot = 0;
   1027 	if (unit >= d->d_umax)
   1028 		d->d_umax = unit + 1;
   1029 	return (i);
   1030 }
   1031 
   1032 /*
   1033  * Add the named device as attaching to the named attribute (or perhaps
   1034  * another device instead) plus unit number.
   1035  */
   1036 void
   1037 adddev(const char *name, const char *at, struct loclist *loclist, int flags)
   1038 {
   1039 	struct devi *i;		/* the new instance */
   1040 	struct pspec *p;	/* and its pspec */
   1041 	struct attr *attr;	/* attribute that allows attach */
   1042 	struct devbase *ib;	/* i->i_base */
   1043 	struct devbase *ab;	/* not NULL => at another dev */
   1044 	struct attrlist *al;
   1045 	struct deva *iba;	/* devbase attachment used */
   1046 	const char *cp;
   1047 	int atunit;
   1048 	char atbuf[NAMESIZE];
   1049 	int hit;
   1050 
   1051 	ab = NULL;
   1052 	iba = NULL;
   1053 	if (at == NULL) {
   1054 		/* "at root" */
   1055 		p = NULL;
   1056 		if ((i = getdevi(name)) == NULL)
   1057 			goto bad;
   1058 		/*
   1059 		 * Must warn about i_unit > 0 later, after taking care of
   1060 		 * the STAR cases (we could do non-star's here but why
   1061 		 * bother?).  Make sure this device can be at root.
   1062 		 */
   1063 		ib = i->i_base;
   1064 		hit = 0;
   1065 		for (iba = ib->d_ahead; iba != NULL; iba = iba->d_bsame)
   1066 			if (onlist(iba->d_atlist, NULL)) {
   1067 				hit = 1;
   1068 				break;
   1069 			}
   1070 		if (!hit) {
   1071 			cfgerror("`%s' cannot attach to the root", ib->d_name);
   1072 			i->i_active = DEVI_BROKEN;
   1073 			goto bad;
   1074 		}
   1075 		attr = &errattr;	/* a convenient "empty" attr */
   1076 	} else {
   1077 		if (split(at, strlen(at), atbuf, sizeof atbuf, &atunit)) {
   1078 			cfgerror("invalid attachment name `%s'", at);
   1079 			/* (void)getdevi(name); -- ??? */
   1080 			goto bad;
   1081 		}
   1082 		if ((i = getdevi(name)) == NULL)
   1083 			goto bad;
   1084 		ib = i->i_base;
   1085 
   1086 		/*
   1087 		 * Devices can attach to two types of things: Attributes,
   1088 		 * and other devices (which have the appropriate attributes
   1089 		 * to allow attachment).
   1090 		 *
   1091 		 * (1) If we're attached to an attribute, then we don't need
   1092 		 *     look at the parent base device to see what attributes
   1093 		 *     it has, and make sure that we can attach to them.
   1094 		 *
   1095 		 * (2) If we're attached to a real device (i.e. named in
   1096 		 *     the config file), we want to remember that so that
   1097 		 *     at cross-check time, if the device we're attached to
   1098 		 *     is missing but other devices which also provide the
   1099 		 *     attribute are present, we don't get a false "OK."
   1100 		 *
   1101 		 * (3) If the thing we're attached to is an attribute
   1102 		 *     but is actually named in the config file, we still
   1103 		 *     have to remember its devbase.
   1104 		 */
   1105 		cp = intern(atbuf);
   1106 
   1107 		/* Figure out parent's devbase, to satisfy case (3). */
   1108 		ab = ht_lookup(devbasetab, cp);
   1109 
   1110 		/* Find out if it's an attribute. */
   1111 		attr = ht_lookup(attrtab, cp);
   1112 
   1113 		/* Make sure we're _really_ attached to the attr.  Case (1). */
   1114 		if (attr != NULL && onlist(attr->a_devs, ib))
   1115 			goto findattachment;
   1116 
   1117 		/*
   1118 		 * Else a real device, and not just an attribute.  Case (2).
   1119 		 *
   1120 		 * Have to work a bit harder to see whether we have
   1121 		 * something like "tg0 at esp0" (where esp is merely
   1122 		 * not an attribute) or "tg0 at nonesuch0" (where
   1123 		 * nonesuch is not even a device).
   1124 		 */
   1125 		if (ab == NULL) {
   1126 			cfgerror("%s at %s: `%s' unknown",
   1127 			    name, at, atbuf);
   1128 			i->i_active = DEVI_BROKEN;
   1129 			goto bad;
   1130 		}
   1131 
   1132 		/*
   1133 		 * See if the named parent carries an attribute
   1134 		 * that allows it to supervise device ib.
   1135 		 */
   1136 		for (al = ab->d_attrs; al != NULL; al = al->al_next) {
   1137 			attr = al->al_this;
   1138 			if (onlist(attr->a_devs, ib))
   1139 				goto findattachment;
   1140 		}
   1141 		cfgerror("`%s' cannot attach to `%s'", ib->d_name, atbuf);
   1142 		i->i_active = DEVI_BROKEN;
   1143 		goto bad;
   1144 
   1145  findattachment:
   1146 		/*
   1147 		 * Find the parent spec.  If a matching one has not yet been
   1148 		 * created, create one.
   1149 		 */
   1150 		p = getpspec(attr, ab, atunit);
   1151 		p->p_devs = newnv(NULL, NULL, i, 0, p->p_devs);
   1152 
   1153 		/* find out which attachment it uses */
   1154 		hit = 0;
   1155 		for (iba = ib->d_ahead; iba != NULL; iba = iba->d_bsame)
   1156 			if (onlist(iba->d_atlist, attr)) {
   1157 				hit = 1;
   1158 				break;
   1159 			}
   1160 		if (!hit)
   1161 			panic("adddev: can't figure out attachment");
   1162 	}
   1163 	if ((i->i_locs = fixloc(name, attr, loclist)) == NULL) {
   1164 		i->i_active = DEVI_BROKEN;
   1165 		goto bad;
   1166 	}
   1167 	i->i_at = at;
   1168 	i->i_pspec = p;
   1169 	i->i_atdeva = iba;
   1170 	i->i_cfflags = flags;
   1171 
   1172 	*iba->d_ipp = i;
   1173 	iba->d_ipp = &i->i_asame;
   1174 
   1175 	/* all done, fall into ... */
   1176  bad:
   1177 	loclist_destroy(loclist);
   1178 	return;
   1179 }
   1180 
   1181 void
   1182 deldevi(const char *name, const char *at)
   1183 {
   1184 	struct devi *firsti, *i;
   1185 	struct devbase *d;
   1186 	int unit;
   1187 	char base[NAMESIZE];
   1188 
   1189 	if (split(name, strlen(name), base, sizeof base, &unit)) {
   1190 		cfgerror("invalid device name `%s'", name);
   1191 		return;
   1192 	}
   1193 	d = ht_lookup(devbasetab, intern(base));
   1194 	if (d == NULL) {
   1195 		cfgerror("%s: unknown device `%s'", name, base);
   1196 		return;
   1197 	}
   1198 	if (d->d_ispseudo) {
   1199 		cfgerror("%s: %s is a pseudo-device", name, base);
   1200 		return;
   1201 	}
   1202 	if ((firsti = ht_lookup(devitab, name)) == NULL) {
   1203 		cfgerror("`%s' not defined", name);
   1204 		return;
   1205 	}
   1206 	if (at == NULL && firsti->i_at == NULL) {
   1207 		/* 'at root' */
   1208 		remove_devi(firsti);
   1209 		return;
   1210 	} else if (at != NULL)
   1211 		for (i = firsti; i != NULL; i = i->i_alias)
   1212 			if (i->i_active != DEVI_BROKEN &&
   1213 			    strcmp(at, i->i_at) == 0) {
   1214 				remove_devi(i);
   1215 				return;
   1216 			}
   1217 	cfgerror("`%s' at `%s' not found", name, at ? at : "root");
   1218 }
   1219 
   1220 static void
   1221 remove_devi(struct devi *i)
   1222 {
   1223 	struct devbase *d = i->i_base;
   1224 	struct devi *f, *j, **ppi;
   1225 	struct deva *iba;
   1226 
   1227 	f = ht_lookup(devitab, i->i_name);
   1228 	if (f == NULL)
   1229 		panic("remove_devi(): instance %s disappeared from devitab",
   1230 		    i->i_name);
   1231 
   1232 	if (i->i_active == DEVI_BROKEN) {
   1233 		cfgerror("not removing broken instance `%s'", i->i_name);
   1234 		return;
   1235 	}
   1236 
   1237 	/*
   1238 	 * We have the device instance, i.
   1239 	 * We have to:
   1240 	 *   - delete the alias
   1241 	 *
   1242 	 *      If the devi was an alias of an already listed devi, all is
   1243 	 *      good we don't have to do more.
   1244 	 *      If it was the first alias, we have to replace i's entry in
   1245 	 *      d's list by its first alias.
   1246 	 *      If it was the only entry, we must remove i's entry from d's
   1247 	 *      list.
   1248 	 */
   1249 	if (i != f) {
   1250 		for (j = f; j->i_alias != i; j = j->i_alias);
   1251 		j->i_alias = i->i_alias;
   1252 	} else {
   1253 		if (i->i_alias == NULL) {
   1254 			/* No alias, must unlink the entry from devitab */
   1255 			ht_remove(devitab, i->i_name);
   1256 			j = i->i_bsame;
   1257 		} else {
   1258 			/* Or have the first alias replace i in d's list */
   1259 			i->i_alias->i_bsame = i->i_bsame;
   1260 			j = i->i_alias;
   1261 			if (i == f)
   1262 				ht_replace(devitab, i->i_name, i->i_alias);
   1263 		}
   1264 
   1265 		/*
   1266 		 *   - remove/replace the instance from the devbase's list
   1267 		 *
   1268 		 * A double-linked list would make this much easier.  Oh, well,
   1269 		 * what is done is done.
   1270 		 */
   1271 		for (ppi = &d->d_ihead;
   1272 		    *ppi != NULL && *ppi != i && (*ppi)->i_bsame != i;
   1273 		    ppi = &(*ppi)->i_bsame);
   1274 		if (*ppi == NULL)
   1275 			panic("deldev: dev (%s) doesn't list the devi"
   1276 			    " (%s at %s)", d->d_name, i->i_name, i->i_at);
   1277 		f = *ppi;
   1278 		if (f == i)
   1279 			/* That implies d->d_ihead == i */
   1280 			*ppi = j;
   1281 		else
   1282 			(*ppi)->i_bsame = j;
   1283 		if (d->d_ipp == &i->i_bsame) {
   1284 			if (i->i_alias == NULL) {
   1285 				if (f == i)
   1286 					d->d_ipp = &d->d_ihead;
   1287 				else
   1288 					d->d_ipp = &f->i_bsame;
   1289 			} else
   1290 				d->d_ipp = &i->i_alias->i_bsame;
   1291 		}
   1292 	}
   1293 	/*
   1294 	 *   - delete the attachment instance
   1295 	 */
   1296 	iba = i->i_atdeva;
   1297 	for (ppi = &iba->d_ihead;
   1298 	    *ppi != NULL && *ppi != i && (*ppi)->i_asame != i;
   1299 	    ppi = &(*ppi)->i_asame);
   1300 	if (*ppi == NULL)
   1301 		panic("deldev: deva (%s) doesn't list the devi (%s)",
   1302 		    iba->d_name, i->i_name);
   1303 	f = *ppi;
   1304 	if (f == i)
   1305 		/* That implies iba->d_ihead == i */
   1306 		*ppi = i->i_asame;
   1307 	else
   1308 		(*ppi)->i_asame = i->i_asame;
   1309 	if (iba->d_ipp == &i->i_asame) {
   1310 		if (f == i)
   1311 			iba->d_ipp = &iba->d_ihead;
   1312 		else
   1313 			iba->d_ipp = &f->i_asame;
   1314 	}
   1315 	/*
   1316 	 *   - delete the pspec
   1317 	 */
   1318 	if (i->i_pspec) {
   1319 		struct pspec *p = i->i_pspec;
   1320 		struct nvlist *nv, *onv;
   1321 
   1322 		/* Double-linked nvlist anyone? */
   1323 		for (nv = p->p_devs; nv->nv_next != NULL; nv = nv->nv_next) {
   1324 			if (nv->nv_next && nv->nv_next->nv_ptr == i) {
   1325 				onv = nv->nv_next;
   1326 				nv->nv_next = onv->nv_next;
   1327 				nvfree(onv);
   1328 				break;
   1329 			}
   1330 			if (nv->nv_ptr == i) {
   1331 				/* nv is p->p_devs in that case */
   1332 				p->p_devs = nv->nv_next;
   1333 				nvfree(nv);
   1334 				break;
   1335 			}
   1336 		}
   1337 		if (p->p_devs == NULL)
   1338 			TAILQ_REMOVE(&allpspecs, p, p_list);
   1339 	}
   1340 	/*
   1341 	 *   - delete the alldevi entry
   1342 	 */
   1343 	TAILQ_REMOVE(&alldevi, i, i_next);
   1344 	ndevi--;
   1345 	/*
   1346 	 * Put it in deaddevitab
   1347 	 *
   1348 	 * Each time a devi is removed, devilevel is increased so that later on
   1349 	 * it is possible to tell if an instance was added before or after the
   1350 	 * removal of its parent.
   1351 	 *
   1352 	 * For active instances, i_level contains the number of devi removed so
   1353 	 * far, and for dead devis, it contains its index.
   1354 	 */
   1355 	i->i_level = devilevel++;
   1356 	i->i_alias = NULL;
   1357 	f = ht_lookup(deaddevitab, i->i_name);
   1358 	if (f == NULL) {
   1359 		if (ht_insert(deaddevitab, i->i_name, i))
   1360 			panic("remove_devi(%s) - can't add to deaddevitab",
   1361 			    i->i_name);
   1362 	} else {
   1363 		for (j = f; j->i_alias != NULL; j = j->i_alias);
   1364 		j->i_alias = i;
   1365 	}
   1366 	/*
   1367 	 *   - reconstruct d->d_umax
   1368 	 */
   1369 	d->d_umax = 0;
   1370 	for (i = d->d_ihead; i != NULL; i = i->i_bsame)
   1371 		if (i->i_unit >= d->d_umax)
   1372 			d->d_umax = i->i_unit + 1;
   1373 }
   1374 
   1375 void
   1376 deldeva(const char *at)
   1377 {
   1378 	int unit;
   1379 	const char *cp;
   1380 	struct devbase *d, *ad;
   1381 	struct devi *i, *j;
   1382 	struct attr *a;
   1383 	struct pspec *p;
   1384 	struct nvlist *nv, *stack = NULL;
   1385 
   1386 	if (at == NULL) {
   1387 		TAILQ_FOREACH(i, &alldevi, i_next)
   1388 			if (i->i_at == NULL)
   1389 				stack = newnv(NULL, NULL, i, 0, stack);
   1390 	} else {
   1391 		int l;
   1392 
   1393 		l = strlen(at) - 1;
   1394 		if (at[l] == '?' || isdigit((unsigned char)at[l])) {
   1395 			char base[NAMESIZE];
   1396 
   1397 			if (split(at, l+1, base, sizeof base, &unit)) {
   1398 				cfgerror("invalid attachment name `%s'", at);
   1399 				return;
   1400 			}
   1401 			cp = intern(base);
   1402 		} else {
   1403 			cp = intern(at);
   1404 			unit = STAR;
   1405 		}
   1406 
   1407 		ad = ht_lookup(devbasetab, cp);
   1408 		a = ht_lookup(attrtab, cp);
   1409 		if (a == NULL) {
   1410 			cfgerror("unknown attachment attribute or device `%s'",
   1411 			    cp);
   1412 			return;
   1413 		}
   1414 		if (!a->a_iattr) {
   1415 			cfgerror("plain attribute `%s' cannot have children",
   1416 			    a->a_name);
   1417 			return;
   1418 		}
   1419 
   1420 		/*
   1421 		 * remove_devi() makes changes to the devbase's list and the
   1422 		 * alias list, * so the actual deletion of the instances must
   1423 		 * be delayed.
   1424 		 */
   1425 		for (nv = a->a_devs; nv != NULL; nv = nv->nv_next) {
   1426 			d = nv->nv_ptr;
   1427 			for (i = d->d_ihead; i != NULL; i = i->i_bsame)
   1428 				for (j = i; j != NULL; j = j->i_alias) {
   1429 					/* Ignore devices at root */
   1430 					if (j->i_at == NULL)
   1431 						continue;
   1432 					p = j->i_pspec;
   1433 					/*
   1434 					 * There are three cases:
   1435 					 *
   1436 					 * 1.  unit is not STAR.  Consider 'at'
   1437 					 *     to be explicit, even if it
   1438 					 *     references an interface
   1439 					 *     attribute.
   1440 					 *
   1441 					 * 2.  unit is STAR and 'at' references
   1442 					 *     a real device.  Look for pspec
   1443 					 *     that have a matching p_atdev
   1444 					 *     field.
   1445 					 *
   1446 					 * 3.  unit is STAR and 'at' references
   1447 					 *     an interface attribute.  Look
   1448 					 *     for pspec that have a matching
   1449 					 *     p_iattr field.
   1450 					 */
   1451 					if ((unit != STAR &&        /* Case */
   1452 					     !strcmp(j->i_at, at)) ||  /* 1 */
   1453 					    (unit == STAR &&
   1454 					     ((ad != NULL &&        /* Case */
   1455 					       p->p_atdev == ad) ||    /* 2 */
   1456 					      (ad == NULL &&        /* Case */
   1457 					       p->p_iattr == a))))     /* 3 */
   1458 						stack = newnv(NULL, NULL, j, 0,
   1459 						    stack);
   1460 				}
   1461 		}
   1462 	}
   1463 
   1464 	for (nv = stack; nv != NULL; nv = nv->nv_next)
   1465 		remove_devi(nv->nv_ptr);
   1466 	nvfreel(stack);
   1467 }
   1468 
   1469 void
   1470 deldev(const char *name)
   1471 {
   1472 	int l;
   1473 	struct devi *firsti, *i;
   1474 	struct nvlist *nv, *stack = NULL;
   1475 
   1476 	l = strlen(name) - 1;
   1477 	if (name[l] == '*' || isdigit((unsigned char)name[l])) {
   1478 		/* `no mydev0' or `no mydev*' */
   1479 		firsti = ht_lookup(devitab, name);
   1480 		if (firsti == NULL) {
   1481 			cfgerror("unknown instance %s", name);
   1482 			return;
   1483 		}
   1484 		for (i = firsti; i != NULL; i = i->i_alias)
   1485 			stack = newnv(NULL, NULL, i, 0, stack);
   1486 	} else {
   1487 		struct devbase *d = ht_lookup(devbasetab, name);
   1488 
   1489 		if (d == NULL) {
   1490 			cfgerror("unknown device %s", name);
   1491 			return;
   1492 		}
   1493 		if (d->d_ispseudo) {
   1494 			cfgerror("%s is a pseudo-device; "
   1495 			    "use \"no pseudo-device %s\" instead", name,
   1496 			    name);
   1497 			return;
   1498 		}
   1499 
   1500 		for (firsti = d->d_ihead; firsti != NULL;
   1501 		    firsti = firsti->i_bsame)
   1502 			for (i = firsti; i != NULL; i = i->i_alias)
   1503 				stack = newnv(NULL, NULL, i, 0, stack);
   1504 	}
   1505 
   1506 	for (nv = stack; nv != NULL; nv = nv->nv_next)
   1507 		remove_devi(nv->nv_ptr);
   1508 	nvfreel(stack);
   1509 }
   1510 
   1511 /*
   1512  * Insert given device "name" into devroottab.  In case "name"
   1513  * designates a pure interface attribute, create a fake device
   1514  * instance for the attribute and insert that into the roottab
   1515  * (this scheme avoids mucking around with the orphanage analysis).
   1516  */
   1517 void
   1518 addpseudoroot(const char *name)
   1519 {
   1520 	char buf[NAMESIZE];
   1521 	int unit;
   1522 	struct attr *attr;
   1523 	struct devi *i;
   1524 	struct deva *iba;
   1525 	struct devbase *ib;
   1526 
   1527 	if (split(name, strlen(name), buf, sizeof(buf), &unit)) {
   1528 		cfgerror("invalid pseudo-root name `%s'", name);
   1529 		return;
   1530 	}
   1531 
   1532 	/*
   1533 	 * Prefer device because devices with locators define an
   1534 	 * implicit interface attribute.  However, if a device is
   1535 	 * not available, try to attach to the interface attribute.
   1536 	 * This makes sure adddev() doesn't get confused when we
   1537 	 * are really attaching to a device (alternatively we maybe
   1538 	 * could specify a non-NULL atlist to defdevattach() below).
   1539 	 */
   1540 	ib = ht_lookup(devbasetab, intern(buf));
   1541 	if (ib == NULL) {
   1542 		struct devbase *fakedev;
   1543 		char fakename[NAMESIZE];
   1544 
   1545 		attr = ht_lookup(attrtab, intern(buf));
   1546 		if (!(attr && attr->a_iattr)) {
   1547 			cfgerror("pseudo-root `%s' not available", name);
   1548 			return;
   1549 		}
   1550 
   1551 		/*
   1552 		 * here we cheat a bit: create a fake devbase with the
   1553 		 * interface attribute and instantiate it.  quick, cheap,
   1554 		 * dirty & bad for you, much like the stuff in the fridge.
   1555 		 * and, it works, since the pseudoroot device is not included
   1556 		 * in ioconf, just used by config to make sure we start from
   1557 		 * the right place.
   1558 		 */
   1559 		snprintf(fakename, sizeof(fakename), "%s_devattrs", buf);
   1560 		fakedev = getdevbase(intern(fakename));
   1561 		fakedev->d_isdef = 1;
   1562 		fakedev->d_ispseudo = 0;
   1563 		fakedev->d_attrs = attrlist_cons(NULL, attr);
   1564 		defdevattach(NULL, fakedev, NULL, NULL);
   1565 
   1566 		if (unit == STAR)
   1567 			snprintf(buf, sizeof(buf), "%s*", fakename);
   1568 		else
   1569 			snprintf(buf, sizeof(buf), "%s%d", fakename, unit);
   1570 		name = buf;
   1571 	}
   1572 
   1573 	/* ok, everything should be set up, so instantiate a fake device */
   1574 	i = getdevi(name);
   1575 	if (i == NULL)
   1576 		panic("device `%s' expected to be present", name);
   1577 	ib = i->i_base;
   1578 	iba = ib->d_ahead;
   1579 
   1580 	i->i_atdeva = iba;
   1581 	i->i_cfflags = 0;
   1582 	i->i_locs = fixloc(name, &errattr, NULL);
   1583 	i->i_pseudoroot = 1;
   1584 	i->i_active = DEVI_ORPHAN; /* set active by kill_orphans() */
   1585 
   1586 	*iba->d_ipp = i;
   1587 	iba->d_ipp = &i->i_asame;
   1588 
   1589 	ht_insert(devroottab, ib->d_name, ib);
   1590 }
   1591 
   1592 void
   1593 addpseudo(const char *name, int number)
   1594 {
   1595 	struct devbase *d;
   1596 	struct devi *i;
   1597 
   1598 	d = ht_lookup(devbasetab, name);
   1599 	if (d == NULL) {
   1600 		cfgerror("undefined pseudo-device %s", name);
   1601 		return;
   1602 	}
   1603 	if (!d->d_ispseudo) {
   1604 		cfgerror("%s is a real device, not a pseudo-device", name);
   1605 		return;
   1606 	}
   1607 	if (ht_lookup(devitab, name) != NULL) {
   1608 		cfgerror("`%s' already defined", name);
   1609 		return;
   1610 	}
   1611 	i = newdevi(name, number - 1, d);	/* foo 16 => "foo0..foo15" */
   1612 	if (ht_insert(devitab, name, i))
   1613 		panic("addpseudo(%s)", name);
   1614 	/* Useful to retrieve the instance from the devbase */
   1615 	d->d_ihead = i;
   1616 	i->i_active = DEVI_ACTIVE;
   1617 	TAILQ_INSERT_TAIL(&allpseudo, i, i_next);
   1618 }
   1619 
   1620 void
   1621 delpseudo(const char *name)
   1622 {
   1623 	struct devbase *d;
   1624 	struct devi *i;
   1625 
   1626 	d = ht_lookup(devbasetab, name);
   1627 	if (d == NULL) {
   1628 		cfgerror("undefined pseudo-device %s", name);
   1629 		return;
   1630 	}
   1631 	if (!d->d_ispseudo) {
   1632 		cfgerror("%s is a real device, not a pseudo-device", name);
   1633 		return;
   1634 	}
   1635 	if ((i = ht_lookup(devitab, name)) == NULL) {
   1636 		cfgerror("`%s' not defined", name);
   1637 		return;
   1638 	}
   1639 	d->d_umax = 0;		/* clear neads-count entries */
   1640 	d->d_ihead = NULL;	/* make sure it won't be considered active */
   1641 	TAILQ_REMOVE(&allpseudo, i, i_next);
   1642 	if (ht_remove(devitab, name))
   1643 		panic("delpseudo(%s) - can't remove from devitab", name);
   1644 	if (ht_insert(deaddevitab, name, i))
   1645 		panic("delpseudo(%s) - can't add to deaddevitab", name);
   1646 }
   1647 
   1648 void
   1649 adddevm(const char *name, devmajor_t cmajor, devmajor_t bmajor,
   1650 	struct condexpr *cond, struct nvlist *nv_nodes)
   1651 {
   1652 	struct devm *dm;
   1653 
   1654 	if (cmajor != NODEVMAJOR && (cmajor < 0 || cmajor >= 4096)) {
   1655 		cfgerror("character major %d is invalid", cmajor);
   1656 		condexpr_destroy(cond);
   1657 		nvfreel(nv_nodes);
   1658 		return;
   1659 	}
   1660 
   1661 	if (bmajor != NODEVMAJOR && (bmajor < 0 || bmajor >= 4096)) {
   1662 		cfgerror("block major %d is invalid", bmajor);
   1663 		condexpr_destroy(cond);
   1664 		nvfreel(nv_nodes);
   1665 		return;
   1666 	}
   1667 	if (cmajor == NODEVMAJOR && bmajor == NODEVMAJOR) {
   1668 		cfgerror("both character/block majors are not specified");
   1669 		condexpr_destroy(cond);
   1670 		nvfreel(nv_nodes);
   1671 		return;
   1672 	}
   1673 
   1674 	dm = ecalloc(1, sizeof(*dm));
   1675 	dm->dm_srcfile = yyfile;
   1676 	dm->dm_srcline = currentline();
   1677 	dm->dm_name = name;
   1678 	dm->dm_cmajor = cmajor;
   1679 	dm->dm_bmajor = bmajor;
   1680 	dm->dm_opts = cond;
   1681 	dm->dm_devnodes = nv_nodes;
   1682 
   1683 	TAILQ_INSERT_TAIL(&alldevms, dm, dm_next);
   1684 
   1685 	maxcdevm = MAX(maxcdevm, dm->dm_cmajor);
   1686 	maxbdevm = MAX(maxbdevm, dm->dm_bmajor);
   1687 }
   1688 
   1689 int
   1690 fixdevis(void)
   1691 {
   1692 	struct devi *i;
   1693 	int error = 0;
   1694 
   1695 	TAILQ_FOREACH(i, &alldevi, i_next)
   1696 		if (i->i_active == DEVI_ACTIVE)
   1697 			selectbase(i->i_base, i->i_atdeva);
   1698 		else if (i->i_active == DEVI_ORPHAN) {
   1699 			/*
   1700 			 * At this point, we can't have instances for which
   1701 			 * i_at or i_pspec are NULL.
   1702 			 */
   1703 			++error;
   1704 			cfgxerror(i->i_srcfile, i->i_lineno,
   1705 			    "`%s at %s' is orphaned (%s `%s' found)",
   1706 			    i->i_name, i->i_at, i->i_pspec->p_atunit == WILD ?
   1707 			    "nothing matching" : "no", i->i_at);
   1708 		} else if (vflag && i->i_active == DEVI_IGNORED)
   1709 			cfgxwarn(i->i_srcfile, i->i_lineno, "ignoring "
   1710 			    "explicitly orphaned instance `%s at %s'",
   1711 			    i->i_name, i->i_at);
   1712 
   1713 	if (error)
   1714 		return error;
   1715 
   1716 	TAILQ_FOREACH(i, &allpseudo, i_next)
   1717 		if (i->i_active == DEVI_ACTIVE)
   1718 			selectbase(i->i_base, NULL);
   1719 	return 0;
   1720 }
   1721 
   1722 /*
   1723  * Look up a parent spec, creating a new one if it does not exist.
   1724  */
   1725 static struct pspec *
   1726 getpspec(struct attr *attr, struct devbase *ab, int atunit)
   1727 {
   1728 	struct pspec *p;
   1729 
   1730 	TAILQ_FOREACH(p, &allpspecs, p_list) {
   1731 		if (p->p_iattr == attr &&
   1732 		    p->p_atdev == ab &&
   1733 		    p->p_atunit == atunit)
   1734 			return (p);
   1735 	}
   1736 
   1737 	p = ecalloc(1, sizeof(*p));
   1738 
   1739 	p->p_iattr = attr;
   1740 	p->p_atdev = ab;
   1741 	p->p_atunit = atunit;
   1742 	p->p_inst = npspecs++;
   1743 	p->p_active = 0;
   1744 
   1745 	TAILQ_INSERT_TAIL(&allpspecs, p, p_list);
   1746 
   1747 	return (p);
   1748 }
   1749 
   1750 /*
   1751  * Define a new instance of a specific device.
   1752  */
   1753 static struct devi *
   1754 getdevi(const char *name)
   1755 {
   1756 	struct devi *i, *firsti;
   1757 	struct devbase *d;
   1758 	int unit;
   1759 	char base[NAMESIZE];
   1760 
   1761 	if (split(name, strlen(name), base, sizeof base, &unit)) {
   1762 		cfgerror("invalid device name `%s'", name);
   1763 		return (NULL);
   1764 	}
   1765 	d = ht_lookup(devbasetab, intern(base));
   1766 	if (d == NULL) {
   1767 		cfgerror("%s: unknown device `%s'", name, base);
   1768 		return (NULL);
   1769 	}
   1770 	if (d->d_ispseudo) {
   1771 		cfgerror("%s: %s is a pseudo-device", name, base);
   1772 		return (NULL);
   1773 	}
   1774 	firsti = ht_lookup(devitab, name);
   1775 	i = newdevi(name, unit, d);
   1776 	if (firsti == NULL) {
   1777 		if (ht_insert(devitab, name, i))
   1778 			panic("getdevi(%s)", name);
   1779 		*d->d_ipp = i;
   1780 		d->d_ipp = &i->i_bsame;
   1781 	} else {
   1782 		while (firsti->i_alias)
   1783 			firsti = firsti->i_alias;
   1784 		firsti->i_alias = i;
   1785 	}
   1786 	TAILQ_INSERT_TAIL(&alldevi, i, i_next);
   1787 	ndevi++;
   1788 	return (i);
   1789 }
   1790 
   1791 static const char *
   1792 concat(const char *name, int c)
   1793 {
   1794 	size_t len;
   1795 	char buf[NAMESIZE];
   1796 
   1797 	len = strlen(name);
   1798 	if (len + 2 > sizeof(buf)) {
   1799 		cfgerror("device name `%s%c' too long", name, c);
   1800 		len = sizeof(buf) - 2;
   1801 	}
   1802 	memmove(buf, name, len);
   1803 	buf[len] = c;
   1804 	buf[len + 1] = 0;
   1805 	return (intern(buf));
   1806 }
   1807 
   1808 const char *
   1809 starref(const char *name)
   1810 {
   1811 
   1812 	return (concat(name, '*'));
   1813 }
   1814 
   1815 const char *
   1816 wildref(const char *name)
   1817 {
   1818 
   1819 	return (concat(name, '?'));
   1820 }
   1821 
   1822 /*
   1823  * Split a name like "foo0" into base name (foo) and unit number (0).
   1824  * Return 0 on success.  To make this useful for names like "foo0a",
   1825  * the length of the "foo0" part is one of the arguments.
   1826  */
   1827 static int
   1828 split(const char *name, size_t nlen, char *base, size_t bsize, int *aunit)
   1829 {
   1830 	const char *cp;
   1831 	int c;
   1832 	size_t l;
   1833 
   1834 	l = nlen;
   1835 	if (l < 2 || l >= bsize || isdigit((unsigned char)*name))
   1836 		return (1);
   1837 	c = (u_char)name[--l];
   1838 	if (!isdigit(c)) {
   1839 		if (c == '*')
   1840 			*aunit = STAR;
   1841 		else if (c == '?')
   1842 			*aunit = WILD;
   1843 		else
   1844 			return (1);
   1845 	} else {
   1846 		cp = &name[l];
   1847 		while (isdigit((unsigned char)cp[-1]))
   1848 			l--, cp--;
   1849 		*aunit = atoi(cp);
   1850 	}
   1851 	memmove(base, name, l);
   1852 	base[l] = 0;
   1853 	return (0);
   1854 }
   1855 
   1856 void
   1857 selectattr(struct attr *a)
   1858 {
   1859 
   1860 	(void)ht_insert(selecttab, a->a_name, __UNCONST(a->a_name));
   1861 	CFGDBG(3, "attr selected `%s'", a->a_name);
   1862 }
   1863 
   1864 /*
   1865  * We have an instance of the base foo, so select it and all its
   1866  * attributes for "optional foo".
   1867  */
   1868 static void
   1869 selectbase(struct devbase *d, struct deva *da)
   1870 {
   1871 	struct attr *a;
   1872 	struct attrlist *al;
   1873 
   1874 	(void)ht_insert(selecttab, d->d_name, __UNCONST(d->d_name));
   1875 	CFGDBG(3, "devbase selected `%s'", d->d_name);
   1876 	for (al = d->d_attrs; al != NULL; al = al->al_next) {
   1877 		a = al->al_this;
   1878 		expandattr(a, selectattr);
   1879 	}
   1880 	if (da != NULL) {
   1881 		(void)ht_insert(selecttab, da->d_name, __UNCONST(da->d_name));
   1882 		CFGDBG(3, "devattr selected `%s'", da->d_name);
   1883 		for (al = da->d_attrs; al != NULL; al = al->al_next) {
   1884 			a = al->al_this;
   1885 			expandattr(a, selectattr);
   1886 		}
   1887 	}
   1888 }
   1889 
   1890 /*
   1891  * Is the given pointer on the given list of pointers?
   1892  */
   1893 int
   1894 onlist(struct nvlist *nv, void *ptr)
   1895 {
   1896 	for (; nv != NULL; nv = nv->nv_next)
   1897 		if (nv->nv_ptr == ptr)
   1898 			return (1);
   1899 	return (0);
   1900 }
   1901 
   1902 static char *
   1903 extend(char *p, const char *name)
   1904 {
   1905 	size_t l;
   1906 
   1907 	l = strlen(name);
   1908 	memmove(p, name, l);
   1909 	p += l;
   1910 	*p++ = ',';
   1911 	*p++ = ' ';
   1912 	return (p);
   1913 }
   1914 
   1915 /*
   1916  * Check that we got all required locators, and default any that are
   1917  * given as "?" and have defaults.  Return 0 on success.
   1918  */
   1919 static const char **
   1920 fixloc(const char *name, struct attr *attr, struct loclist *got)
   1921 {
   1922 	struct loclist *m, *n;
   1923 	int ord;
   1924 	const char **lp;
   1925 	int nmissing, nextra, nnodefault;
   1926 	char *mp, *ep, *ndp;
   1927 	char missing[1000], extra[1000], nodefault[1000];
   1928 	static const char *nullvec[1];
   1929 
   1930 	/*
   1931 	 * Look for all required locators, and number the given ones
   1932 	 * according to the required order.  While we are numbering,
   1933 	 * set default values for defaulted locators.
   1934 	 */
   1935 	if (attr->a_loclen == 0)	/* e.g., "at root" */
   1936 		lp = nullvec;
   1937 	else
   1938 		lp = emalloc((attr->a_loclen + 1) * sizeof(const char *));
   1939 	for (n = got; n != NULL; n = n->ll_next)
   1940 		n->ll_num = -1;
   1941 	nmissing = 0;
   1942 	mp = missing;
   1943 	/* yes, this is O(mn), but m and n should be small */
   1944 	for (ord = 0, m = attr->a_locs; m != NULL; m = m->ll_next, ord++) {
   1945 		for (n = got; n != NULL; n = n->ll_next) {
   1946 			if (n->ll_name == m->ll_name) {
   1947 				n->ll_num = ord;
   1948 				break;
   1949 			}
   1950 		}
   1951 		if (n == NULL && m->ll_num == 0) {
   1952 			nmissing++;
   1953 			mp = extend(mp, m->ll_name);
   1954 		}
   1955 		lp[ord] = m->ll_string;
   1956 	}
   1957 	if (ord != attr->a_loclen)
   1958 		panic("fixloc");
   1959 	lp[ord] = NULL;
   1960 	nextra = 0;
   1961 	ep = extra;
   1962 	nnodefault = 0;
   1963 	ndp = nodefault;
   1964 	for (n = got; n != NULL; n = n->ll_next) {
   1965 		if (n->ll_num >= 0) {
   1966 			if (n->ll_string != NULL)
   1967 				lp[n->ll_num] = n->ll_string;
   1968 			else if (lp[n->ll_num] == NULL) {
   1969 				nnodefault++;
   1970 				ndp = extend(ndp, n->ll_name);
   1971 			}
   1972 		} else {
   1973 			nextra++;
   1974 			ep = extend(ep, n->ll_name);
   1975 		}
   1976 	}
   1977 	if (nextra) {
   1978 		ep[-2] = 0;	/* kill ", " */
   1979 		cfgerror("%s: extraneous locator%s: %s",
   1980 		    name, nextra > 1 ? "s" : "", extra);
   1981 	}
   1982 	if (nmissing) {
   1983 		mp[-2] = 0;
   1984 		cfgerror("%s: must specify %s", name, missing);
   1985 	}
   1986 	if (nnodefault) {
   1987 		ndp[-2] = 0;
   1988 		cfgerror("%s: cannot wildcard %s", name, nodefault);
   1989 	}
   1990 	if (nmissing || nnodefault) {
   1991 		free(lp);
   1992 		lp = NULL;
   1993 	}
   1994 	return (lp);
   1995 }
   1996 
   1997 void
   1998 setversion(int newver)
   1999 {
   2000 	if (newver > CONFIG_VERSION)
   2001 		cfgerror("your sources require a newer version of config(1) "
   2002 		    "-- please rebuild it.");
   2003 	else if (newver < CONFIG_MINVERSION)
   2004 		cfgerror("your sources are out of date -- please update.");
   2005 	else
   2006 		version = newver;
   2007 }
   2008