Patrick Welche <prlw1@cam.ac.uk>

[netbsd-mini2440.git] / usr.bin / config / sem.c

/*      $NetBSD: sem.c,v 1.32 2009/01/20 18:20:48 drochner Exp $        */

/*
 * Copyright (c) 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This software was developed by the Computer Systems Engineering group
 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
 * contributed to Berkeley.
 *
 * All advertising materials mentioning features or use of this software
 * must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Lawrence Berkeley Laboratories.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      from: @(#)sem.c 8.1 (Berkeley) 6/6/93
 */

#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#endif

#include <sys/param.h>
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <util.h>
#include "defs.h"
#include "sem.h"

/*
 * config semantics.
 */

#define NAMESIZE        100     /* local name buffers */

const char *s_ifnet;            /* magic attribute */
const char *s_qmark;
const char *s_none;

static struct hashtab *cfhashtab;       /* for config lookup */
struct hashtab *devitab;                /* etc */

static struct attr errattr;
static struct devbase errdev;
static struct deva errdeva;

static int has_errobj(struct nvlist *, void *);
static struct nvlist *addtoattr(struct nvlist *, struct devbase *);
static int resolve(struct nvlist **, const char *, const char *,
                   struct nvlist *, int);
static struct pspec *getpspec(struct attr *, struct devbase *, int);
static struct devi *newdevi(const char *, int, struct devbase *d);
static struct devi *getdevi(const char *);
static void remove_devi(struct devi *);
static const char *concat(const char *, int);
static char *extend(char *, const char *);
static int split(const char *, size_t, char *, size_t, int *);
static void selectbase(struct devbase *, struct deva *);
static const char **fixloc(const char *, struct attr *, struct nvlist *);
static const char *makedevstr(devmajor_t, devminor_t);
static const char *major2name(devmajor_t);
static devmajor_t dev2major(struct devbase *);

extern const char *yyfile;
extern int vflag;

void
initsem(void)
{

        attrtab = ht_new();
        errattr.a_name = "<internal>";

        TAILQ_INIT(&allbases);

        TAILQ_INIT(&alldevas);

        TAILQ_INIT(&allpspecs);

        cfhashtab = ht_new();
        TAILQ_INIT(&allcf);

        TAILQ_INIT(&alldevi);
        errdev.d_name = "<internal>";

        TAILQ_INIT(&allpseudo);

        TAILQ_INIT(&alldevms);

        s_ifnet = intern("ifnet");
        s_qmark = intern("?");
        s_none = intern("none");
}

/* Name of include file just ended (set in scan.l) */
extern const char *lastfile;

void
enddefs(void)
{
        struct devbase *dev;

        TAILQ_FOREACH(dev, &allbases, d_next) {
                if (!dev->d_isdef) {
                        (void)fprintf(stderr,
                            "%s: device `%s' used but not defined\n",
                            lastfile, dev->d_name);
                        errors++;
                        continue;
                }
        }
        if (errors) {
                (void)fprintf(stderr, "*** Stop.\n");
                exit(1);
        }
}

void
setdefmaxusers(int min, int def, int max)
{

        if (min < 1 || min > def || def > max)
                cfgerror("maxusers must have 1 <= min (%d) <= default (%d) "
                    "<= max (%d)", min, def, max);
        else {
                minmaxusers = min;
                defmaxusers = def;
                maxmaxusers = max;
        }
}

void
setmaxusers(int n)
{

        if (maxusers == n) {
                cfgerror("duplicate maxusers parameter");
                return;
        }
        if (vflag && maxusers != 0)
                cfgwarn("warning: maxusers already defined");
        maxusers = n;
        if (n < minmaxusers) {
                cfgerror("warning: minimum of %d maxusers assumed",
                    minmaxusers);
                errors--;       /* take it away */
                maxusers = minmaxusers;
        } else if (n > maxmaxusers) {
                cfgerror("warning: maxusers (%d) > %d", n, maxmaxusers);
                errors--;
        }
}

void
setident(const char *i)
{

        ident = intern(i);
}

/*
 * Define an attribute, optionally with an interface (a locator list)
 * and a set of attribute-dependencies.
 *
 * Attribute dependencies MAY NOT be interface attributes.
 *
 * Since an empty locator list is logically different from "no interface",
 * all locator lists include a dummy head node, which we discard here.
 */
int
defattr(const char *name, struct nvlist *locs, struct nvlist *deps,
    int devclass)
{
        struct attr *a, *dep;
        struct nvlist *nv;
        int len;

        if (locs != NULL && devclass)
                panic("defattr(%s): locators and devclass", name);

        if (deps != NULL && devclass)
                panic("defattr(%s): dependencies and devclass", name);

        /*
         * If this attribute depends on any others, make sure none of
         * the dependencies are interface attributes.
         */
        for (nv = deps; nv != NULL; nv = nv->nv_next) {
                dep = nv->nv_ptr;
                if (dep->a_iattr) {
                        cfgerror("`%s' dependency `%s' is an interface "
                            "attribute", name, dep->a_name);
                        return (1);
                }
        }

        a = ecalloc(1, sizeof *a);
        if (ht_insert(attrtab, name, a)) {
                free(a);
                cfgerror("attribute `%s' already defined", name);
                nvfreel(locs);
                return (1);
        }

        a->a_name = name;
        if (locs != NULL) {
                a->a_iattr = 1;
                a->a_locs = locs->nv_next;
                nvfree(locs);
        } else {
                a->a_iattr = 0;
                a->a_locs = NULL;
        }
        if (devclass) {
                char classenum[256], *cp;
                int errored = 0;

                (void)snprintf(classenum, sizeof(classenum), "DV_%s", name);
                for (cp = classenum + 3; *cp; cp++) {
                        if (!errored &&
                            (!isalnum((unsigned char)*cp) ||
                              (isalpha((unsigned char)*cp) && !islower((unsigned char)*cp)))) {
                                cfgerror("device class names must be "
                                    "lower-case alphanumeric characters");
                                errored = 1;
                        }
                        *cp = toupper((unsigned char)*cp);
                }
                a->a_devclass = intern(classenum);
        } else
                a->a_devclass = NULL;
        len = 0;
        for (nv = a->a_locs; nv != NULL; nv = nv->nv_next)
                len++;
        a->a_loclen = len;
        a->a_devs = NULL;
        a->a_refs = NULL;
        a->a_deps = deps;
        a->a_expanding = 0;

        /* Expand the attribute to check for cycles in the graph. */
        expandattr(a, NULL);

        return (0);
}

/*
 * Return true if the given `error object' is embedded in the given
 * pointer list.
 */
static int
has_errobj(struct nvlist *nv, void *obj)
{

        for (; nv != NULL; nv = nv->nv_next)
                if (nv->nv_ptr == obj)
                        return (1);
        return (0);
}

/*
 * Return true if the given attribute is embedded in the given
 * pointer list.
 */
int
has_attr(struct nvlist *nv, const char *attr)
{
        struct attr *a;

        if ((a = getattr(attr)) == NULL)
                return (0);

        for (; nv != NULL; nv = nv->nv_next)
                if (nv->nv_ptr == a)
                        return (1);
        return (0);
}

/*
 * Add a device base to a list in an attribute (actually, to any list).
 * Note that this does not check for duplicates, and does reverse the
 * list order, but no one cares anyway.
 */
static struct nvlist *
addtoattr(struct nvlist *l, struct devbase *dev)
{
        struct nvlist *n;

        n = newnv(NULL, NULL, dev, 0, l);
        return (n);
}

/*
 * Define a device.  This may (or may not) also define an interface
 * attribute and/or refer to existing attributes.
 */
void
defdev(struct devbase *dev, struct nvlist *loclist, struct nvlist *attrs,
       int ispseudo)
{
        struct nvlist *nv;
        struct attr *a;

        if (dev == &errdev)
                goto bad;
        if (dev->d_isdef) {
                cfgerror("redefinition of `%s'", dev->d_name);
                goto bad;
        }

        dev->d_isdef = 1;
        if (has_errobj(attrs, &errattr))
                goto bad;

        /*
         * Handle implicit attribute definition from locator list.  Do
         * this before scanning the `at' list so that we can have, e.g.:
         *      device foo at other, foo { slot = -1 }
         * (where you can plug in a foo-bus extender to a foo-bus).
         */
        if (loclist != NULL) {
                nv = loclist;
                loclist = NULL; /* defattr disposes of them for us */
                if (defattr(dev->d_name, nv, NULL, 0))
                        goto bad;
                attrs = newnv(dev->d_name, NULL, getattr(dev->d_name), 0,
                    attrs);

        }

        /*
         * Pseudo-devices can have children.  Consider them as
         * attaching at root.
         */
        if (ispseudo) {
                for (nv = attrs; nv != NULL; nv = nv->nv_next)
                        if (((struct attr *)(nv->nv_ptr))->a_iattr)
                                break;
                if (nv != NULL) {
                        if (ispseudo < 2) {
                                if (version >= 20080610)
                                        cfgerror("interface attribute on "
                                         "non-device pseudo `%s'", dev->d_name);
                                else {
                                        ispseudo = 2;
                                }
                        }
                        ht_insert(devroottab, dev->d_name, dev);
                }
        }

        /* Committed!  Set up fields. */
        dev->d_ispseudo = ispseudo;
        dev->d_attrs = attrs;
        dev->d_classattr = NULL;                /* for now */

        /*
         * For each interface attribute this device refers to, add this
         * device to its reference list.  This makes, e.g., finding all
         * "scsi"s easier.
         *
         * While looking through the attributes, set up the device
         * class if any are devclass attributes (and error out if the
         * device has two classes).
         */
        for (nv = attrs; nv != NULL; nv = nv->nv_next) {
                a = nv->nv_ptr;
                if (a->a_iattr)
                        a->a_refs = addtoattr(a->a_refs, dev);
                if (a->a_devclass != NULL) {
                        if (dev->d_classattr != NULL) {
                                cfgerror("device `%s' has multiple classes "
                                    "(`%s' and `%s')",
                                    dev->d_name, dev->d_classattr->a_name,
                                    a->a_name);
                        }
                        dev->d_classattr = a;
                }
        }
        return;
 bad:
        nvfreel(loclist);
        nvfreel(attrs);
}

/*
 * Look up a devbase.  Also makes sure it is a reasonable name,
 * i.e., does not end in a digit or contain special characters.
 */
struct devbase *
getdevbase(const char *name)
{
        const u_char *p;
        struct devbase *dev;

        p = (const u_char *)name;
        if (!isalpha(*p))
                goto badname;
        while (*++p) {
                if (!isalnum(*p) && *p != '_')
                        goto badname;
        }
        if (isdigit(*--p)) {
 badname:
                cfgerror("bad device base name `%s'", name);
                return (&errdev);
        }
        dev = ht_lookup(devbasetab, name);
        if (dev == NULL) {
                dev = ecalloc(1, sizeof *dev);
                dev->d_name = name;
                dev->d_isdef = 0;
                dev->d_major = NODEVMAJOR;
                dev->d_attrs = NULL;
                dev->d_ihead = NULL;
                dev->d_ipp = &dev->d_ihead;
                dev->d_ahead = NULL;
                dev->d_app = &dev->d_ahead;
                dev->d_umax = 0;
                TAILQ_INSERT_TAIL(&allbases, dev, d_next);
                if (ht_insert(devbasetab, name, dev))
                        panic("getdevbase(%s)", name);
        }
        return (dev);
}

/*
 * Define some of a device's allowable parent attachments.
 * There may be a list of (plain) attributes.
 */
void
defdevattach(struct deva *deva, struct devbase *dev, struct nvlist *atlist,
             struct nvlist *attrs)
{
        struct nvlist *nv;
        struct attr *a;
        struct deva *da;

        if (dev == &errdev)
                goto bad;
        if (deva == NULL)
                deva = getdevattach(dev->d_name);
        if (deva == &errdeva)
                goto bad;
        if (!dev->d_isdef) {
                cfgerror("attaching undefined device `%s'", dev->d_name);
                goto bad;
        }
        if (deva->d_isdef) {
                cfgerror("redefinition of `%s'", deva->d_name);
                goto bad;
        }
        if (dev->d_ispseudo) {
                cfgerror("pseudo-devices can't attach");
                goto bad;
        }

        deva->d_isdef = 1;
        if (has_errobj(attrs, &errattr))
                goto bad;
        for (nv = attrs; nv != NULL; nv = nv->nv_next) {
                a = nv->nv_ptr;
                if (a == &errattr)
                        continue;               /* already complained */
                if (a->a_iattr || a->a_devclass != NULL)
                        cfgerror("`%s' is not a plain attribute", a->a_name);
        }

        /* Committed!  Set up fields. */
        deva->d_attrs = attrs;
        deva->d_atlist = atlist;
        deva->d_devbase = dev;

        /*
         * Turn the `at' list into interface attributes (map each
         * nv_name to an attribute, or to NULL for root), and add
         * this device to those attributes, so that children can
         * be listed at this particular device if they are supported
         * by that attribute.
         */
        for (nv = atlist; nv != NULL; nv = nv->nv_next) {
                if (nv->nv_name == NULL)
                        nv->nv_ptr = a = NULL;  /* at root */
                else
                        nv->nv_ptr = a = getattr(nv->nv_name);
                if (a == &errattr)
                        continue;               /* already complained */

                /*
                 * Make sure that an attachment spec doesn't
                 * already say how to attach to this attribute.
                 */
                for (da = dev->d_ahead; da != NULL; da = da->d_bsame)
                        if (onlist(da->d_atlist, a))
                                cfgerror("attach at `%s' already done by `%s'",
                                     a ? a->a_name : "root", da->d_name);

                if (a == NULL) {
                        ht_insert(devroottab, dev->d_name, dev);
                        continue;               /* at root; don't add */
                }
                if (!a->a_iattr)
                        cfgerror("%s cannot be at plain attribute `%s'",
                            dev->d_name, a->a_name);
                else
                        a->a_devs = addtoattr(a->a_devs, dev);
        }

        /* attach to parent */
        *dev->d_app = deva;
        dev->d_app = &deva->d_bsame;
        return;
 bad:
        nvfreel(atlist);
        nvfreel(attrs);
}

/*
 * Look up a device attachment.  Also makes sure it is a reasonable
 * name, i.e., does not contain digits or special characters.
 */
struct deva *
getdevattach(const char *name)
{
        const u_char *p;
        struct deva *deva;

        p = (const u_char *)name;
        if (!isalpha(*p))
                goto badname;
        while (*++p) {
                if (!isalnum(*p) && *p != '_')
                        goto badname;
        }
        if (isdigit(*--p)) {
 badname:
                cfgerror("bad device attachment name `%s'", name);
                return (&errdeva);
        }
        deva = ht_lookup(devatab, name);
        if (deva == NULL) {
                deva = ecalloc(1, sizeof *deva);
                deva->d_name = name;
                deva->d_bsame = NULL;
                deva->d_isdef = 0;
                deva->d_devbase = NULL;
                deva->d_atlist = NULL;
                deva->d_attrs = NULL;
                deva->d_ihead = NULL;
                deva->d_ipp = &deva->d_ihead;
                TAILQ_INSERT_TAIL(&alldevas, deva, d_next);
                if (ht_insert(devatab, name, deva))
                        panic("getdeva(%s)", name);
        }
        return (deva);
}

/*
 * Look up an attribute.
 */
struct attr *
getattr(const char *name)
{
        struct attr *a;

        if ((a = ht_lookup(attrtab, name)) == NULL) {
                cfgerror("undefined attribute `%s'", name);
                a = &errattr;
        }
        return (a);
}

/*
 * Recursively expand an attribute and its dependencies, checking for
 * cycles, and invoking a callback for each attribute found.
 */
void
expandattr(struct attr *a, void (*callback)(struct attr *))
{
        struct nvlist *nv;
        struct attr *dep;

        if (a->a_expanding) {
                cfgerror("circular dependency on attribute `%s'", a->a_name);
                return;
        }

        a->a_expanding = 1;

        /* First expand all of this attribute's dependencies. */
        for (nv = a->a_deps; nv != NULL; nv = nv->nv_next) {
                dep = nv->nv_ptr;
                expandattr(dep, callback);
        }

        /* ...and now invoke the callback for ourself. */
        if (callback != NULL)
                (*callback)(a);

        a->a_expanding = 0;
}

/*
 * Set the major device number for a device, so that it can be used
 * as a root/dumps "on" device in a configuration.
 */
void
setmajor(struct devbase *d, devmajor_t n)
{

        if (d != &errdev && d->d_major != NODEVMAJOR)
                cfgerror("device `%s' is already major %d",
                    d->d_name, d->d_major);
        else
                d->d_major = n;
}

const char *
major2name(devmajor_t maj)
{
        struct devbase *dev;
        struct devm *dm;

        if (!do_devsw) {
                TAILQ_FOREACH(dev, &allbases, d_next) {
                        if (dev->d_major == maj)
                                return (dev->d_name);
                }
        } else {
                TAILQ_FOREACH(dm, &alldevms, dm_next) {
                        if (dm->dm_bmajor == maj)
                                return (dm->dm_name);
                }
        }
        return (NULL);
}

devmajor_t
dev2major(struct devbase *dev)
{
        struct devm *dm;

        if (!do_devsw)
                return (dev->d_major);

        TAILQ_FOREACH(dm, &alldevms, dm_next) {
                if (strcmp(dm->dm_name, dev->d_name) == 0)
                        return (dm->dm_bmajor);
        }
        return (NODEVMAJOR);
}

/*
 * Make a string description of the device at maj/min.
 */
static const char *
makedevstr(devmajor_t maj, devminor_t min)
{
        const char *devicename;
        char buf[32];

        devicename = major2name(maj);
        if (devicename == NULL)
                (void)snprintf(buf, sizeof(buf), "<%d/%d>", maj, min);
        else
                (void)snprintf(buf, sizeof(buf), "%s%d%c", devicename,
                    min / maxpartitions, (min % maxpartitions) + 'a');

        return (intern(buf));
}

/*
 * Map things like "ra0b" => makedev(major("ra"), 0*maxpartitions + 'b'-'a').
 * Handle the case where the device number is given but there is no
 * corresponding name, and map NULL to the default.
 */
static int
resolve(struct nvlist **nvp, const char *name, const char *what,
        struct nvlist *dflt, int part)
{
        struct nvlist *nv;
        struct devbase *dev;
        const char *cp;
        devmajor_t maj;
        devminor_t min;
        int i, l;
        int unit;
        char buf[NAMESIZE];

        if ((part -= 'a') >= maxpartitions || part < 0)
                panic("resolve");
        if ((nv = *nvp) == NULL) {
                dev_t   d = NODEV;
                /*
                 * Apply default.  Easiest to do this by number.
                 * Make sure to retain NODEVness, if this is dflt's disposition.
                 */
                if ((dev_t)dflt->nv_num != NODEV) {
                        maj = major(dflt->nv_num);
                        min = ((minor(dflt->nv_num) / maxpartitions) *
                            maxpartitions) + part;
                        d = makedev(maj, min);
                        cp = makedevstr(maj, min);
                } else
                        cp = NULL;
                *nvp = nv = newnv(NULL, cp, NULL, d, NULL);
        }
        if ((dev_t)nv->nv_num != NODEV) {
                /*
                 * By the numbers.  Find the appropriate major number
                 * to make a name.
                 */
                maj = major(nv->nv_num);
                min = minor(nv->nv_num);
                nv->nv_str = makedevstr(maj, min);
                return (0);
        }

        if (nv->nv_str == NULL || nv->nv_str == s_qmark)
                /*
                 * Wildcarded or unspecified; leave it as NODEV.
                 */
                return (0);

        /*
         * The normal case: things like "ra2b".  Check for partition
         * suffix, remove it if there, and split into name ("ra") and
         * unit (2).
         */
        l = i = strlen(nv->nv_str);
        cp = &nv->nv_str[l];
        if (l > 1 && *--cp >= 'a' && *cp < 'a' + maxpartitions &&
            isdigit((unsigned char)cp[-1])) {
                l--;
                part = *cp - 'a';
        }
        cp = nv->nv_str;
        if (split(cp, l, buf, sizeof buf, &unit)) {
                cfgerror("%s: invalid %s device name `%s'", name, what, cp);
                return (1);
        }
        dev = ht_lookup(devbasetab, intern(buf));
        if (dev == NULL) {
                cfgerror("%s: device `%s' does not exist", name, buf);
                return (1);
        }

        /*
         * Check for the magic network interface attribute, and
         * don't bother making a device number.
         */
        if (has_attr(dev->d_attrs, s_ifnet)) {
                nv->nv_num = NODEV;
                nv->nv_ifunit = unit;   /* XXX XXX XXX */
        } else {
                maj = dev2major(dev);
                if (maj == NODEVMAJOR) {
                        cfgerror("%s: can't make %s device from `%s'",
                            name, what, nv->nv_str);
                        return (1);
                }
                nv->nv_num = makedev(maj, unit * maxpartitions + part);
        }

        nv->nv_name = dev->d_name;
        return (0);
}

/*
 * Add a completed configuration to the list.
 */
void
addconf(struct config *cf0)
{
        struct config *cf;
        const char *name;

        name = cf0->cf_name;
        cf = ecalloc(1, sizeof *cf);
        if (ht_insert(cfhashtab, name, cf)) {
                cfgerror("configuration `%s' already defined", name);
                free(cf);
                goto bad;
        }
        *cf = *cf0;

        /*
         * Resolve the root device.
         */
        if (cf->cf_root == NULL) {
                cfgerror("%s: no root device specified", name);
                goto bad;
        }
        if (cf->cf_root && cf->cf_root->nv_str != s_qmark) {
                struct nvlist *nv;
                nv = cf->cf_root;
                if (resolve(&cf->cf_root, name, "root", nv, 'a'))
                        goto bad;
        }

        /*
         * Resolve the dump device.
         */
        if (cf->cf_dump == NULL || cf->cf_dump->nv_str == s_qmark) {
                /*
                 * Wildcarded dump device is equivalent to unspecified.
                 */
                cf->cf_dump = NULL;
        } else if (cf->cf_dump->nv_str == s_none) {
                /*
                 * Operator has requested that no dump device should be
                 * configured; do nothing.
                 */
        } else {
                if (resolve(&cf->cf_dump, name, "dumps", cf->cf_dump, 'b'))
                        goto bad;
        }

        /* Wildcarded fstype is `unspecified'. */
        if (cf->cf_fstype == s_qmark)
                cf->cf_fstype = NULL;

        TAILQ_INSERT_TAIL(&allcf, cf, cf_next);
        return;
 bad:
        nvfreel(cf0->cf_root);
        nvfreel(cf0->cf_dump);
}

void
setconf(struct nvlist **npp, const char *what, struct nvlist *v)
{

        if (*npp != NULL) {
                cfgerror("duplicate %s specification", what);
                nvfreel(v);
        } else
                *npp = v;
}

void
delconf(const char *name)
{
        struct config *cf;

        if (ht_lookup(cfhashtab, name) == NULL) {
                cfgerror("configuration `%s' undefined", name);
                return;
        }
        (void)ht_remove(cfhashtab, name);

        TAILQ_FOREACH(cf, &allcf, cf_next)
                if (!strcmp(cf->cf_name, name))
                        break;
        if (cf == NULL)
                panic("lost configuration `%s'", name);

        TAILQ_REMOVE(&allcf, cf, cf_next);
}

void
setfstype(const char **fstp, const char *v)
{

        if (*fstp != NULL) {
                cfgerror("multiple fstype specifications");
                return;
        }

        if (v != s_qmark && OPT_FSOPT(v)) {
                cfgerror("\"%s\" is not a configured file system", v);
                return;
        }

        *fstp = v;
}

static struct devi *
newdevi(const char *name, int unit, struct devbase *d)
{
        struct devi *i;

        i = ecalloc(1, sizeof *i);
        i->i_name = name;
        i->i_unit = unit;
        i->i_base = d;
        i->i_bsame = NULL;
        i->i_asame = NULL;
        i->i_alias = NULL;
        i->i_at = NULL;
        i->i_pspec = NULL;
        i->i_atdeva = NULL;
        i->i_locs = NULL;
        i->i_cfflags = 0;
        i->i_lineno = currentline();
        i->i_srcfile = yyfile;
        i->i_active = DEVI_ORPHAN; /* Proper analysis comes later */
        i->i_level = devilevel;
        if (unit >= d->d_umax)
                d->d_umax = unit + 1;
        return (i);
}

/*
 * Add the named device as attaching to the named attribute (or perhaps
 * another device instead) plus unit number.
 */
void
adddev(const char *name, const char *at, struct nvlist *loclist, int flags)
{
        struct devi *i;         /* the new instance */
        struct pspec *p;        /* and its pspec */
        struct attr *attr;      /* attribute that allows attach */
        struct devbase *ib;     /* i->i_base */
        struct devbase *ab;     /* not NULL => at another dev */
        struct nvlist *nv;
        struct deva *iba;       /* devbase attachment used */
        const char *cp;
        int atunit;
        char atbuf[NAMESIZE];
        int hit;

        ab = NULL;
        iba = NULL;
        if (at == NULL) {
                /* "at root" */
                p = NULL;
                if ((i = getdevi(name)) == NULL)
                        goto bad;
                /*
                 * Must warn about i_unit > 0 later, after taking care of
                 * the STAR cases (we could do non-star's here but why
                 * bother?).  Make sure this device can be at root.
                 */
                ib = i->i_base;
                hit = 0;
                for (iba = ib->d_ahead; iba != NULL; iba = iba->d_bsame)
                        if (onlist(iba->d_atlist, NULL)) {
                                hit = 1;
                                break;
                        }
                if (!hit) {
                        cfgerror("`%s' cannot attach to the root", ib->d_name);
                        i->i_active = DEVI_BROKEN;
                        goto bad;
                }
                attr = &errattr;        /* a convenient "empty" attr */
        } else {
                if (split(at, strlen(at), atbuf, sizeof atbuf, &atunit)) {
                        cfgerror("invalid attachment name `%s'", at);
                        /* (void)getdevi(name); -- ??? */
                        goto bad;
                }
                if ((i = getdevi(name)) == NULL)
                        goto bad;
                ib = i->i_base;

                /*
                 * Devices can attach to two types of things: Attributes,
                 * and other devices (which have the appropriate attributes
                 * to allow attachment).
                 *
                 * (1) If we're attached to an attribute, then we don't need
                 *     look at the parent base device to see what attributes
                 *     it has, and make sure that we can attach to them.    
                 *
                 * (2) If we're attached to a real device (i.e. named in
                 *     the config file), we want to remember that so that
                 *     at cross-check time, if the device we're attached to
                 *     is missing but other devices which also provide the
                 *     attribute are present, we don't get a false "OK."
                 *
                 * (3) If the thing we're attached to is an attribute
                 *     but is actually named in the config file, we still
                 *     have to remember its devbase.
                 */
                cp = intern(atbuf);

                /* Figure out parent's devbase, to satisfy case (3). */
                ab = ht_lookup(devbasetab, cp);

                /* Find out if it's an attribute. */
                attr = ht_lookup(attrtab, cp);

                /* Make sure we're _really_ attached to the attr.  Case (1). */
                if (attr != NULL && onlist(attr->a_devs, ib))
                        goto findattachment;

                /*
                 * Else a real device, and not just an attribute.  Case (2).
                 *
                 * Have to work a bit harder to see whether we have
                 * something like "tg0 at esp0" (where esp is merely
                 * not an attribute) or "tg0 at nonesuch0" (where
                 * nonesuch is not even a device).
                 */
                if (ab == NULL) {
                        cfgerror("%s at %s: `%s' unknown",
                            name, at, atbuf);
                        i->i_active = DEVI_BROKEN;
                        goto bad;
                }

                /*
                 * See if the named parent carries an attribute
                 * that allows it to supervise device ib.
                 */
                for (nv = ab->d_attrs; nv != NULL; nv = nv->nv_next) {
                        attr = nv->nv_ptr;
                        if (onlist(attr->a_devs, ib))
                                goto findattachment;
                }
                cfgerror("`%s' cannot attach to `%s'", ib->d_name, atbuf);
                i->i_active = DEVI_BROKEN;
                goto bad;

 findattachment:
                /*
                 * Find the parent spec.  If a matching one has not yet been
                 * created, create one.
                 */
                p = getpspec(attr, ab, atunit);
                p->p_devs = newnv(NULL, NULL, i, 0, p->p_devs);

                /* find out which attachment it uses */
                hit = 0;
                for (iba = ib->d_ahead; iba != NULL; iba = iba->d_bsame)
                        if (onlist(iba->d_atlist, attr)) {
                                hit = 1;
                                break;
                        }
                if (!hit)
                        panic("adddev: can't figure out attachment");
        }
        if ((i->i_locs = fixloc(name, attr, loclist)) == NULL) {
                i->i_active = DEVI_BROKEN;
                goto bad;
        }
        i->i_at = at;
        i->i_pspec = p;
        i->i_atdeva = iba;
        i->i_cfflags = flags;

        *iba->d_ipp = i;
        iba->d_ipp = &i->i_asame;

        /* all done, fall into ... */
 bad:
        nvfreel(loclist);
        return;
}

void
deldevi(const char *name, const char *at)
{
        struct devi *firsti, *i;
        struct devbase *d;
        int unit;
        char base[NAMESIZE];

        if (split(name, strlen(name), base, sizeof base, &unit)) {
                cfgerror("invalid device name `%s'", name);
                return;
        }
        d = ht_lookup(devbasetab, intern(base));
        if (d == NULL) {
                cfgerror("%s: unknown device `%s'", name, base);
                return;
        }
        if (d->d_ispseudo) {
                cfgerror("%s: %s is a pseudo-device", name, base);
                return;
        }
        if ((firsti = ht_lookup(devitab, name)) == NULL) {
                cfgerror("`%s' not defined", name);
                return;
        }
        if (at == NULL && firsti->i_at == NULL) {
                /* 'at root' */
                remove_devi(firsti);
                return;
        } else if (at != NULL)
                for (i = firsti; i != NULL; i = i->i_alias)
                        if (i->i_active != DEVI_BROKEN &&
                            strcmp(at, i->i_at) == 0) {
                                remove_devi(i);
                                return;
                        }
        cfgerror("`%s' at `%s' not found", name, at ? at : "root");
}

static void
remove_devi(struct devi *i)
{
        struct devbase *d = i->i_base;
        struct devi *f, *j, **ppi;
        struct deva *iba;

        f = ht_lookup(devitab, i->i_name);
        if (f == NULL)
                panic("remove_devi(): instance %s disappeared from devitab",
                    i->i_name);

        if (i->i_active == DEVI_BROKEN) {
                cfgerror("not removing broken instance `%s'", i->i_name);
                return;
        }

        /*
         * We have the device instance, i.
         * We have to:
         *   - delete the alias
         *
         *      If the devi was an alias of an already listed devi, all is
         *      good we don't have to do more.
         *      If it was the first alias, we have to replace i's entry in
         *      d's list by its first alias.
         *      If it was the only entry, we must remove i's entry from d's
         *      list.
         */
        if (i != f) {
                for (j = f; j->i_alias != i; j = j->i_alias);
                j->i_alias = i->i_alias;
        } else {
                if (i->i_alias == NULL) {
                        /* No alias, must unlink the entry from devitab */
                        ht_remove(devitab, i->i_name);
                        j = i->i_bsame;
                } else {
                        /* Or have the first alias replace i in d's list */
                        i->i_alias->i_bsame = i->i_bsame;
                        j = i->i_alias;
                        if (i == f)
                                ht_replace(devitab, i->i_name, i->i_alias);
                }

                /*
                 *   - remove/replace the instance from the devbase's list
                 *
                 * A double-linked list would make this much easier.  Oh, well,
                 * what is done is done.
                 */
                for (ppi = &d->d_ihead;
                    *ppi != NULL && *ppi != i && (*ppi)->i_bsame != i;
                    ppi = &(*ppi)->i_bsame);
                if (*ppi == NULL)
                        panic("deldev: dev (%s) doesn't list the devi"
                            " (%s at %s)", d->d_name, i->i_name, i->i_at);
                f = *ppi;
                if (f == i)
                        /* That implies d->d_ihead == i */
                        *ppi = j;
                else
                        (*ppi)->i_bsame = j;
                if (d->d_ipp == &i->i_bsame) {
                        if (i->i_alias == NULL) {
                                if (f == i)
                                        d->d_ipp = &d->d_ihead;
                                else
                                        d->d_ipp = &f->i_bsame;
                        } else
                                d->d_ipp = &i->i_alias->i_bsame;
                }
        }
        /*
         *   - delete the attachment instance
         */
        iba = i->i_atdeva;
        for (ppi = &iba->d_ihead;
            *ppi != NULL && *ppi != i && (*ppi)->i_asame != i;
            ppi = &(*ppi)->i_asame);
        if (*ppi == NULL)
                panic("deldev: deva (%s) doesn't list the devi (%s)",
                    iba->d_name, i->i_name);
        f = *ppi;
        if (f == i)
                /* That implies iba->d_ihead == i */
                *ppi = i->i_asame;
        else
                (*ppi)->i_asame = i->i_asame;
        if (iba->d_ipp == &i->i_asame) {
                if (f == i)
                        iba->d_ipp = &iba->d_ihead;
                else
                        iba->d_ipp = &f->i_asame;
        }
        /*
         *   - delete the pspec
         */
        if (i->i_pspec) {
                struct pspec *p = i->i_pspec;
                struct nvlist *nv, *onv;

                /* Double-linked nvlist anyone? */
                for (nv = p->p_devs; nv->nv_next != NULL; nv = nv->nv_next) {
                        if (nv->nv_next && nv->nv_next->nv_ptr == i) {
                                onv = nv->nv_next;
                                nv->nv_next = onv->nv_next;
                                nvfree(onv);
                                break;
                        }
                        if (nv->nv_ptr == i) {
                                /* nv is p->p_devs in that case */
                                p->p_devs = nv->nv_next;
                                nvfree(nv);
                                break;
                        }
                }
                if (p->p_devs == NULL)
                        TAILQ_REMOVE(&allpspecs, p, p_list);
        }
        /*
         *   - delete the alldevi entry
         */
        TAILQ_REMOVE(&alldevi, i, i_next);
        ndevi--;
        /*
         * Put it in deaddevitab
         *
         * Each time a devi is removed, devilevel is increased so that later on
         * it is possible to tell if an instance was added before or after the
         * removal of its parent.
         *
         * For active instances, i_level contains the number of devi removed so
         * far, and for dead devis, it contains its index.
         */
        i->i_level = devilevel++;
        i->i_alias = NULL;
        f = ht_lookup(deaddevitab, i->i_name);
        if (f == NULL) {
                if (ht_insert(deaddevitab, i->i_name, i))
                        panic("remove_devi(%s) - can't add to deaddevitab",
                            i->i_name);
        } else {
                for (j = f; j->i_alias != NULL; j = j->i_alias);
                j->i_alias = i;
        }
        /*
         *   - reconstruct d->d_umax
         */
        d->d_umax = 0;
        for (i = d->d_ihead; i != NULL; i = i->i_bsame)
                if (i->i_unit >= d->d_umax)
                        d->d_umax = i->i_unit + 1;
}

void
deldeva(const char *at)
{
        int unit;
        const char *cp;
        struct devbase *d, *ad;
        struct devi *i, *j;
        struct attr *a;
        struct pspec *p;
        struct nvlist *nv, *stack = NULL;

        if (at == NULL) {
                TAILQ_FOREACH(i, &alldevi, i_next)
                        if (i->i_at == NULL)
                                stack = newnv(NULL, NULL, i, 0, stack);
        } else {
                int l;

                l = strlen(at) - 1;
                if (at[l] == '?' || isdigit((unsigned char)at[l])) {
                        char base[NAMESIZE];

                        if (split(at, l+1, base, sizeof base, &unit)) {
                                cfgerror("invalid attachment name `%s'", at);
                                return;
                        }
                        cp = intern(base);
                } else {
                        cp = intern(at);
                        unit = STAR;
                }

                ad = ht_lookup(devbasetab, cp);
                a = ht_lookup(attrtab, cp);
                if (a == NULL) {
                        cfgerror("unknown attachment attribute or device `%s'",
                            cp);
                        return;
                }
                if (!a->a_iattr) {
                        cfgerror("plain attribute `%s' cannot have children",
                            a->a_name);
                        return;
                }

                /*
                 * remove_devi() makes changes to the devbase's list and the
                 * alias list, * so the actual deletion of the instances must
                 * be delayed.
                 */
                for (nv = a->a_devs; nv != NULL; nv = nv->nv_next) {
                        d = nv->nv_ptr;
                        for (i = d->d_ihead; i != NULL; i = i->i_bsame)
                                for (j = i; j != NULL; j = j->i_alias) {
                                        /* Ignore devices at root */
                                        if (j->i_at == NULL)
                                                continue;
                                        p = j->i_pspec;
                                        /*
                                         * There are three cases:
                                         *
                                         * 1.  unit is not STAR.  Consider 'at'
                                         *     to be explicit, even if it
                                         *     references an interface
                                         *     attribute.
                                         *
                                         * 2.  unit is STAR and 'at' references
                                         *     a real device.  Look for pspec
                                         *     that have a matching p_atdev
                                         *     field.
                                         *
                                         * 3.  unit is STAR and 'at' references
                                         *     an interface attribute.  Look
                                         *     for pspec that have a matching
                                         *     p_iattr field.
                                         */
                                        if ((unit != STAR &&        /* Case */
                                             !strcmp(j->i_at, at)) ||  /* 1 */
                                            (unit == STAR &&
                                             ((ad != NULL &&        /* Case */
                                               p->p_atdev == ad) ||    /* 2 */
                                              (ad == NULL &&        /* Case */
                                               p->p_iattr == a))))     /* 3 */
                                                stack = newnv(NULL, NULL, j, 0,
                                                    stack);
                                }
                }
        }

        for (nv = stack; nv != NULL; nv = nv->nv_next)
                remove_devi(nv->nv_ptr);
        nvfreel(stack);
}

void
deldev(const char *name)
{
        int l;
        struct devi *firsti, *i;
        struct nvlist *nv, *stack = NULL;

        l = strlen(name) - 1;
        if (name[l] == '*' || isdigit((unsigned char)name[l])) {
                /* `no mydev0' or `no mydev*' */
                firsti = ht_lookup(devitab, name);
                if (firsti == NULL) {
                        cfgerror("unknown instance %s", name);
                        return;
                }
                for (i = firsti; i != NULL; i = i->i_alias)
                        stack = newnv(NULL, NULL, i, 0, stack);
        } else {
                struct devbase *d = ht_lookup(devbasetab, name);

                if (d == NULL) {
                        cfgerror("unknown device %s", name);
                        return;
                }
                if (d->d_ispseudo) {
                        cfgerror("%s is a pseudo-device; "
                            "use \"no pseudo-device %s\" instead", name,
                            name);
                        return;
                }

                for (firsti = d->d_ihead; firsti != NULL;
                    firsti = firsti->i_bsame)
                        for (i = firsti; i != NULL; i = i->i_alias)
                                stack = newnv(NULL, NULL, i, 0, stack);
        }

        for (nv = stack; nv != NULL; nv = nv->nv_next)
                remove_devi(nv->nv_ptr);
        nvfreel(stack);
}

void
addpseudo(const char *name, int number)
{
        struct devbase *d;
        struct devi *i;

        d = ht_lookup(devbasetab, name);
        if (d == NULL) {
                cfgerror("undefined pseudo-device %s", name);
                return;
        }
        if (!d->d_ispseudo) {
                cfgerror("%s is a real device, not a pseudo-device", name);
                return;
        }
        if (ht_lookup(devitab, name) != NULL) {
                cfgerror("`%s' already defined", name);
                return;
        }
        i = newdevi(name, number - 1, d);       /* foo 16 => "foo0..foo15" */
        if (ht_insert(devitab, name, i))
                panic("addpseudo(%s)", name);
        /* Useful to retrieve the instance from the devbase */
        d->d_ihead = i;
        i->i_active = DEVI_ACTIVE;
        TAILQ_INSERT_TAIL(&allpseudo, i, i_next);
}

void
delpseudo(const char *name)
{
        struct devbase *d;
        struct devi *i;

        d = ht_lookup(devbasetab, name);
        if (d == NULL) {
                cfgerror("undefined pseudo-device %s", name);
                return;
        }
        if (!d->d_ispseudo) {
                cfgerror("%s is a real device, not a pseudo-device", name);
                return;
        }
        if ((i = ht_lookup(devitab, name)) == NULL) {
                cfgerror("`%s' not defined", name);
                return;
        }
        d->d_umax = 0;          /* clear neads-count entries */
        d->d_ihead = NULL;      /* make sure it won't be considered active */
        TAILQ_REMOVE(&allpseudo, i, i_next);
        if (ht_remove(devitab, name))
                panic("delpseudo(%s) - can't remove from devitab", name);
        if (ht_insert(deaddevitab, name, i))
                panic("delpseudo(%s) - can't add to deaddevitab", name);
}

void
adddevm(const char *name, devmajor_t cmajor, devmajor_t bmajor,
        struct nvlist *nv)
{
        struct devm *dm;

        if (cmajor != NODEVMAJOR && (cmajor < 0 || cmajor >= 4096)) {
                cfgerror("character major %d is invalid", cmajor);
                nvfreel(nv);
                return;
        }

        if (bmajor != NODEVMAJOR && (bmajor < 0 || bmajor >= 4096)) {
                cfgerror("block major %d is invalid", bmajor);
                nvfreel(nv);
                return;
        }
        if (cmajor == NODEVMAJOR && bmajor == NODEVMAJOR) {
                cfgerror("both character/block majors are not specified");
                nvfreel(nv);
                return;
        }

        dm = ecalloc(1, sizeof(*dm));
        dm->dm_srcfile = yyfile;
        dm->dm_srcline = currentline();
        dm->dm_name = name;
        dm->dm_cmajor = cmajor;
        dm->dm_bmajor = bmajor;
        dm->dm_opts = nv;

        TAILQ_INSERT_TAIL(&alldevms, dm, dm_next);

        maxcdevm = MAX(maxcdevm, dm->dm_cmajor);
        maxbdevm = MAX(maxbdevm, dm->dm_bmajor);
}

int
fixdevis(void)
{
        struct devi *i;
        int error = 0;

        TAILQ_FOREACH(i, &alldevi, i_next)
                if (i->i_active == DEVI_ACTIVE)
                        selectbase(i->i_base, i->i_atdeva);
                else if (i->i_active == DEVI_ORPHAN) {
                        /*
                         * At this point, we can't have instances for which
                         * i_at or i_pspec are NULL.
                         */
                        ++error;
                        cfgxerror(i->i_srcfile, i->i_lineno,
                            "`%s at %s' is orphaned (%s `%s' found)", 
                            i->i_name, i->i_at, i->i_pspec->p_atunit == WILD ?
                            "nothing matching" : "no", i->i_at);
                } else if (vflag && i->i_active == DEVI_IGNORED)
                        cfgxwarn(i->i_srcfile, i->i_lineno, "ignoring "
                            "explicitly orphaned instance `%s at %s'",
                            i->i_name, i->i_at);

        if (error)
                return error;

        TAILQ_FOREACH(i, &allpseudo, i_next)
                if (i->i_active == DEVI_ACTIVE)
                        selectbase(i->i_base, NULL);
        return 0;
}

/*
 * Look up a parent spec, creating a new one if it does not exist.
 */
static struct pspec *
getpspec(struct attr *attr, struct devbase *ab, int atunit)
{
        struct pspec *p;

        TAILQ_FOREACH(p, &allpspecs, p_list) {
                if (p->p_iattr == attr &&
                    p->p_atdev == ab &&
                    p->p_atunit == atunit)
                        return (p);
        }

        p = ecalloc(1, sizeof(*p));

        p->p_iattr = attr;
        p->p_atdev = ab;
        p->p_atunit = atunit;
        p->p_inst = npspecs++;
        p->p_active = 0;

        TAILQ_INSERT_TAIL(&allpspecs, p, p_list);

        return (p);
}

/*
 * Define a new instance of a specific device.
 */
static struct devi *
getdevi(const char *name)
{
        struct devi *i, *firsti;
        struct devbase *d;
        int unit;
        char base[NAMESIZE];

        if (split(name, strlen(name), base, sizeof base, &unit)) {
                cfgerror("invalid device name `%s'", name);
                return (NULL);
        }
        d = ht_lookup(devbasetab, intern(base));
        if (d == NULL) {
                cfgerror("%s: unknown device `%s'", name, base);
                return (NULL);
        }
        if (d->d_ispseudo) {
                cfgerror("%s: %s is a pseudo-device", name, base);
                return (NULL);
        }
        firsti = ht_lookup(devitab, name);
        i = newdevi(name, unit, d);
        if (firsti == NULL) {
                if (ht_insert(devitab, name, i))
                        panic("getdevi(%s)", name);
                *d->d_ipp = i;
                d->d_ipp = &i->i_bsame;
        } else {
                while (firsti->i_alias)
                        firsti = firsti->i_alias;
                firsti->i_alias = i;
        }
        TAILQ_INSERT_TAIL(&alldevi, i, i_next);
        ndevi++;
        return (i);
}

static const char *
concat(const char *name, int c)
{
        size_t len;
        char buf[NAMESIZE];

        len = strlen(name);
        if (len + 2 > sizeof(buf)) {
                cfgerror("device name `%s%c' too long", name, c);
                len = sizeof(buf) - 2;
        }
        memmove(buf, name, len);
        buf[len] = c;
        buf[len + 1] = 0;
        return (intern(buf));
}

const char *
starref(const char *name)
{

        return (concat(name, '*'));
}

const char *
wildref(const char *name)
{

        return (concat(name, '?'));
}

/*
 * Split a name like "foo0" into base name (foo) and unit number (0).
 * Return 0 on success.  To make this useful for names like "foo0a",
 * the length of the "foo0" part is one of the arguments.
 */
static int
split(const char *name, size_t nlen, char *base, size_t bsize, int *aunit)
{
        const char *cp;
        int c;
        size_t l;

        l = nlen;
        if (l < 2 || l >= bsize || isdigit((unsigned char)*name))
                return (1);
        c = (u_char)name[--l];
        if (!isdigit(c)) {
                if (c == '*')
                        *aunit = STAR;
                else if (c == '?')
                        *aunit = WILD;
                else
                        return (1);
        } else {
                cp = &name[l];
                while (isdigit((unsigned char)cp[-1]))
                        l--, cp--;
                *aunit = atoi(cp);
        }
        memmove(base, name, l);
        base[l] = 0;
        return (0);
}

void
selectattr(struct attr *a)
{

        (void)ht_insert(selecttab, a->a_name, __UNCONST(a->a_name));
}

/*
 * We have an instance of the base foo, so select it and all its
 * attributes for "optional foo".
 */
static void
selectbase(struct devbase *d, struct deva *da)
{
        struct attr *a;
        struct nvlist *nv;

        (void)ht_insert(selecttab, d->d_name, __UNCONST(d->d_name));
        for (nv = d->d_attrs; nv != NULL; nv = nv->nv_next) {
                a = nv->nv_ptr;
                expandattr(a, selectattr);
        }
        if (da != NULL) {
                (void)ht_insert(selecttab, da->d_name, __UNCONST(da->d_name));
                for (nv = da->d_attrs; nv != NULL; nv = nv->nv_next) {
                        a = nv->nv_ptr;
                        expandattr(a, selectattr);
                }
        }
}

/*
 * Is the given pointer on the given list of pointers?
 */
int
onlist(struct nvlist *nv, void *ptr)
{
        for (; nv != NULL; nv = nv->nv_next)
                if (nv->nv_ptr == ptr)
                        return (1);
        return (0);
}

static char *
extend(char *p, const char *name)
{
        size_t l;

        l = strlen(name);
        memmove(p, name, l);
        p += l;
        *p++ = ',';
        *p++ = ' ';
        return (p);
}

/*
 * Check that we got all required locators, and default any that are
 * given as "?" and have defaults.  Return 0 on success.
 */
static const char **
fixloc(const char *name, struct attr *attr, struct nvlist *got)
{
        struct nvlist *m, *n;
        int ord;
        const char **lp;
        int nmissing, nextra, nnodefault;
        char *mp, *ep, *ndp;
        char missing[1000], extra[1000], nodefault[1000];
        static const char *nullvec[1];

        /*
         * Look for all required locators, and number the given ones
         * according to the required order.  While we are numbering,
         * set default values for defaulted locators.
         */
        if (attr->a_loclen == 0)        /* e.g., "at root" */
                lp = nullvec;
        else
                lp = emalloc((attr->a_loclen + 1) * sizeof(const char *));
        for (n = got; n != NULL; n = n->nv_next)
                n->nv_num = -1;
        nmissing = 0;
        mp = missing;
        /* yes, this is O(mn), but m and n should be small */
        for (ord = 0, m = attr->a_locs; m != NULL; m = m->nv_next, ord++) {
                for (n = got; n != NULL; n = n->nv_next) {
                        if (n->nv_name == m->nv_name) {
                                n->nv_num = ord;
                                break;
                        }
                }
                if (n == NULL && m->nv_num == 0) {
                        nmissing++;
                        mp = extend(mp, m->nv_name);
                }
                lp[ord] = m->nv_str;
        }
        if (ord != attr->a_loclen)
                panic("fixloc");
        lp[ord] = NULL;
        nextra = 0;
        ep = extra;
        nnodefault = 0;
        ndp = nodefault;
        for (n = got; n != NULL; n = n->nv_next) {
                if (n->nv_num >= 0) {
                        if (n->nv_str != NULL)
                                lp[n->nv_num] = n->nv_str;
                        else if (lp[n->nv_num] == NULL) {
                                nnodefault++;
                                ndp = extend(ndp, n->nv_name);
                        }
                } else {
                        nextra++;
                        ep = extend(ep, n->nv_name);
                }
        }
        if (nextra) {
                ep[-2] = 0;     /* kill ", " */
                cfgerror("%s: extraneous locator%s: %s",
                    name, nextra > 1 ? "s" : "", extra);
        }
        if (nmissing) {
                mp[-2] = 0;
                cfgerror("%s: must specify %s", name, missing);
        }
        if (nnodefault) {
                ndp[-2] = 0;
                cfgerror("%s: cannot wildcard %s", name, nodefault);
        }
        if (nmissing || nnodefault) {
                free(lp);
                lp = NULL;
        }
        return (lp);
}

void
setversion(int newver)
{
        if (newver > CONFIG_VERSION)
                cfgerror("your sources require a newer version of config(1) "
                    "-- please rebuild it.");
        else if (newver < CONFIG_MINVERSION)
                cfgerror("your sources are out of date -- please update.");
        else
                version = newver;
}