6659 nvlist_free(NULL) is a no-op

[illumos-gate.git] / usr / src / cmd / fm / modules / common / eversholt / itree.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 *
 * itree.c -- instance tree creation and manipulation
 *
 * this module provides the instance tree
 */

#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <strings.h>
#include "alloc.h"
#include "out.h"
#include "stable.h"
#include "literals.h"
#include "lut.h"
#include "tree.h"
#include "ptree.h"
#include "itree.h"
#include "ipath.h"
#include "iexpr.h"
#include "eval.h"
#include "config.h"

/*
 * struct info contains the state we keep when expanding a prop statement
 * as part of constructing the instance tree.  state kept in struct info
 * is the non-recursive stuff -- the stuff that doesn't need to be on
 * the stack.  the rest of the state that is passed between all the
 * mutually recursive functions, is required to be on the stack since
 * we need to backtrack and recurse as we do the instance tree construction.
 */
struct info {
        struct lut *lut;
        struct node *anp;       /* arrow np */
        struct lut *ex;         /* dictionary of explicit iterators */
        struct config *croot;
} Ninfo;

/*
 * struct wildcardinfo is used to track wildcarded portions of paths.
 *
 * for example, if the epname of an event is "c/d" and the path "a/b/c/d"
 * exists, the wildcard path ewname is filled in with the path "a/b".  when
 * matching is done, epname is temporarily replaced with the concatenation
 * of ewname and epname.
 *
 * a linked list of these structs is used to track the expansion of each
 * event node as it is processed in vmatch() --> vmatch_event() calls.
 */
struct wildcardinfo {
        struct node *nptop;             /* event node fed to vmatch */
        struct node *oldepname;         /* epname without the wildcard part */
        struct node *ewname;            /* wildcard path */
        int got_wc_hz;
        struct wildcardinfo *next;
};

static struct wildcardinfo *wcproot = NULL;

static void vmatch(struct info *infop, struct node *np, struct node *lnp,
    struct node *anp);
static void hmatch(struct info *infop, struct node *np, struct node *nextnp);
static void hmatch_event(struct info *infop, struct node *eventnp,
    struct node *epname, struct config *ncp, struct node *nextnp, int rematch);
static void itree_pbubble(int flags, struct bubble *bp);
static void itree_pruner(void *left, void *right, void *arg);
static void itree_destructor(void *left, void *right, void *arg);
static int itree_set_arrow_traits(struct arrow *ap, struct node *fromev,
    struct node *toev, struct lut *ex);
static void itree_free_arrowlists(struct bubble *bubp, int arrows_too);
static void itree_prune_arrowlists(struct bubble *bubp);
static void arrow_add_within(struct arrow *ap, struct node *xpr);
static struct arrow *itree_add_arrow(struct node *apnode,
    struct node *fromevent, struct node *toevent, struct lut *ex);
static struct event *find_or_add_event(struct info *infop, struct node *np);
static void add_arrow(struct bubble *bp, struct arrow *ap);
static struct constraintlist *itree_add_constraint(struct arrow *arrowp,
    struct node *c);
static struct bubble *itree_add_bubble(struct event *eventp,
    enum bubbletype btype, int nork, int gen);
static void itree_free_bubble(struct bubble *freeme);
static void itree_free_constraints(struct arrow *ap);

/*
 * the following struct contains the state we build up during
 * vertical and horizontal expansion so that generate()
 * has everything it needs to construct the appropriate arrows.
 * after setting up the state by calling:
 *      generate_arrownp()
 *      generate_nork()
 *      generate_new()
 *      generate_from()
 *      generate_to()
 * the actual arrow generation is done by calling:
 *      generate()
 */
static struct {
        int generation;         /* generation number of arrow set */
        int matched;            /* number of matches */
        struct node *arrownp;   /* top-level parse tree for arrow */
        int n;                  /* n value associated with arrow */
        int k;                  /* k value associated with arrow */
        struct node *fromnp;    /* left-hand-side event in parse tree */
        struct node *tonp;      /* right-hand-side event in parse tree */
        struct event *frome;    /* left-hand-side event in instance tree */
        struct event *toe;      /* right-hand-side event in instance tree */
        struct bubble *frombp;  /* bubble arrow comes from */
        struct bubble *tobp;    /* bubble arrow goes to */
} G;

static void
generate_arrownp(struct node *arrownp)
{
        G.arrownp = arrownp;
}

static void
generate_nork(int n, int k)
{
        G.n = n;
        G.k = k;
}

static void
generate_new(void)
{
        G.generation++;
}

static void
generate_from(struct node *fromeventnp)
{
        G.frombp = NULL;
        G.fromnp = fromeventnp;
}

static void
generate_to(struct node *toeventnp)
{
        G.tonp = toeventnp;
}

static void
generate(struct info *infop)
{
        struct arrow *arrowp;

        ASSERT(G.arrownp != NULL);
        ASSERT(G.fromnp != NULL);
        ASSERT(G.tonp != NULL);

        out(O_ALTFP|O_VERB3|O_NONL, "        Arrow \"");
        ptree_name_iter(O_ALTFP|O_VERB3|O_NONL, G.fromnp);
        out(O_ALTFP|O_VERB3|O_NONL, "\" -> \"");
        ptree_name_iter(O_ALTFP|O_VERB3|O_NONL, G.tonp);
        out(O_ALTFP|O_VERB3|O_NONL, "\" ");

        arrowp = itree_add_arrow(G.arrownp, G.fromnp, G.tonp, infop->ex);
        if (arrowp == NULL) {
                out(O_ALTFP|O_VERB3, "(prevented by constraints)");
        } else {
                out(O_ALTFP|O_VERB3, "");
                if (!G.frombp) {
                        G.frome = find_or_add_event(infop, G.fromnp);
                        G.frombp = itree_add_bubble(G.frome, B_FROM, G.n, 0);
                }
                G.toe = find_or_add_event(infop, G.tonp);
                G.tobp = itree_add_bubble(G.toe, B_TO, G.k, G.generation);
                arrowp->tail = G.frombp;
                arrowp->head = G.tobp;
                add_arrow(G.frombp, arrowp);
                add_arrow(G.tobp, arrowp);
        }
}

enum childnode_action {
        CN_NONE,
        CN_DUP
};

static struct node *
tname_dup(struct node *namep, enum childnode_action act)
{
        struct node *retp = NULL;
        const char *file;
        int line;

        if (namep == NULL)
                return (NULL);

        file = namep->file;
        line = namep->line;

        for (; namep != NULL; namep = namep->u.name.next) {
                struct node *newnp = newnode(T_NAME, file, line);

                newnp->u.name.t = namep->u.name.t;
                newnp->u.name.s = namep->u.name.s;
                newnp->u.name.last = newnp;
                newnp->u.name.it = namep->u.name.it;
                newnp->u.name.cp = namep->u.name.cp;

                if (act == CN_DUP) {
                        struct node *npc;

                        npc = namep->u.name.child;
                        if (npc != NULL) {
                                switch (npc->t) {
                                case T_NUM:
                                        newnp->u.name.child =
                                            newnode(T_NUM, file, line);
                                        newnp->u.name.child->u.ull =
                                            npc->u.ull;
                                        break;
                                case T_NAME:
                                        newnp->u.name.child =
                                            tree_name(npc->u.name.s,
                                            npc->u.name.it, file, line);
                                        break;
                                default:
                                        out(O_DIE, "tname_dup: "
                                            "invalid child type %s",
                                            ptree_nodetype2str(npc->t));
                                }
                        }
                }

                if (retp == NULL) {
                        retp = newnp;
                } else {
                        retp->u.name.last->u.name.next = newnp;
                        retp->u.name.last = newnp;
                }
        }

        return (retp);
}

struct prop_wlk_data {
        struct lut *props;
        struct node *epname;
};

static struct lut *props2instance(struct node *, struct node *);

/*
 * let oldepname be a subset of epname.  return the subsection of epname
 * that ends with oldepname.  make each component in the path explicitly
 * instanced (i.e., with a T_NUM child).
 */
static struct node *
tname_dup_to_epname(struct node *oldepname, struct node *epname)
{
        struct node *npref, *npend, *np1, *np2;
        struct node *ret = NULL;
        int foundmatch = 0;

        if (epname == NULL)
                return (NULL);

        /*
         * search for the longest path in epname which contains
         * oldnode->u.event.epname.  set npend to point to just past the
         * end of this path.
         */
        npend = NULL;
        for (npref = epname; npref; npref = npref->u.name.next) {
                if (npref->u.name.s == oldepname->u.name.s) {
                        for (np1 = npref, np2 = oldepname;
                            np1 != NULL && np2 != NULL;
                            np1 = np1->u.name.next, np2 = np2->u.name.next) {
                                if (np1->u.name.s != np2->u.name.s)
                                        break;
                        }
                        if (np2 == NULL) {
                                foundmatch = 1;
                                npend = np1;
                                if (np1 == NULL) {
                                        /* oldepname matched npref up to end */
                                        break;
                                }
                        }
                }
        }

        if (foundmatch == 0) {
                /*
                 * if oldepname could not be found in epname, return a
                 * duplicate of the former.  do not try to instantize
                 * oldepname since it might not be a path.
                 */
                return (tname_dup(oldepname, CN_DUP));
        }

        /*
         * dup (epname -- npend).  all children should be T_NUMs.
         */
        for (npref = epname;
            ! (npref == NULL || npref == npend);
            npref = npref->u.name.next) {
                struct node *newnp = newnode(T_NAME, oldepname->file,
                    oldepname->line);

                newnp->u.name.t = npref->u.name.t;
                newnp->u.name.s = npref->u.name.s;
                newnp->u.name.last = newnp;
                newnp->u.name.it = npref->u.name.it;
                newnp->u.name.cp = npref->u.name.cp;

                newnp->u.name.child = newnode(T_NUM, oldepname->file,
                    oldepname->line);

                if (npref->u.name.child == NULL ||
                    npref->u.name.child->t != T_NUM) {
                        int childnum;

                        ASSERT(npref->u.name.cp != NULL);
                        config_getcompname(npref->u.name.cp, NULL, &childnum);
                        newnp->u.name.child->u.ull = childnum;
                } else {
                        newnp->u.name.child->u.ull =
                            npref->u.name.child->u.ull;
                }

                if (ret == NULL) {
                        ret = newnp;
                } else {
                        ret->u.name.last->u.name.next = newnp;
                        ret->u.name.last = newnp;
                }
        }

        return (ret);
}

/*
 * restriction: oldnode->u.event.epname has to be equivalent to or a subset
 * of epname
 */
static struct node *
tevent_dup_to_epname(struct node *oldnode, struct node *epname)
{
        struct node *ret;

        ret = newnode(T_EVENT, oldnode->file, oldnode->line);
        ret->u.event.ename = tname_dup(oldnode->u.event.ename, CN_NONE);
        ret->u.event.epname = tname_dup_to_epname(oldnode->u.event.epname,
            epname);
        return (ret);
}

static void
nv_instantiate(void *name, void *val, void *arg)
{
        struct prop_wlk_data *pd = (struct prop_wlk_data *)arg;
        struct node *orhs = (struct node *)val;
        struct node *nrhs;

        /* handle engines by instantizing the entire engine */
        if (name == L_engine) {
                ASSERT(orhs->t == T_EVENT);
                ASSERT(orhs->u.event.ename->u.name.t == N_SERD);

                /* there are only SERD engines for now */

                nrhs = newnode(T_SERD, orhs->file, orhs->line);
                nrhs->u.stmt.np = tevent_dup_to_epname(orhs, pd->epname);
                nrhs->u.stmt.lutp = props2instance(orhs, pd->epname);
                pd->props = lut_add(pd->props, name, nrhs, NULL);
                return;
        }

        switch (orhs->t) {
        case T_NUM:
                nrhs = newnode(T_NUM, orhs->file, orhs->line);
                nrhs->u.ull = orhs->u.ull;
                pd->props = lut_add(pd->props, name, nrhs, NULL);
                break;
        case T_TIMEVAL:
                nrhs = newnode(T_TIMEVAL, orhs->file, orhs->line);
                nrhs->u.ull = orhs->u.ull;
                pd->props = lut_add(pd->props, name, nrhs, NULL);
                break;
        case T_NAME:
                nrhs = tname_dup_to_epname(orhs, pd->epname);
                pd->props = lut_add(pd->props, name, nrhs, NULL);
                break;
        case T_EVENT:
                nrhs = tevent_dup_to_epname(orhs, pd->epname);
                pd->props = lut_add(pd->props, name, nrhs, NULL);
                break;
        case T_GLOBID:
                nrhs = newnode(T_GLOBID, orhs->file, orhs->line);
                nrhs->u.globid.s = orhs->u.globid.s;
                pd->props = lut_add(pd->props, name, nrhs, NULL);
                break;
        case T_FUNC:
                /* for T_FUNC, we don't duplicate it, just point to node */
                pd->props = lut_add(pd->props, name, orhs, NULL);
                break;
        default:
                out(O_DIE, "unexpected nvpair value type %s",
                    ptree_nodetype2str(((struct node *)val)->t));
        }
}

static struct lut *
props2instance(struct node *eventnp, struct node *epname)
{
        struct prop_wlk_data pd;

        pd.props = NULL;
        pd.epname = epname;

        ASSERT(eventnp->u.event.declp != NULL);
        lut_walk(eventnp->u.event.declp->u.stmt.lutp, nv_instantiate, &pd);
        return (pd.props);
}

/*ARGSUSED*/
static void
instances_destructor(void *left, void *right, void *arg)
{
        struct node *dn = (struct node *)right;

        if (dn->t == T_SERD) {
                /* we allocated the lut during itree_create(), so free it */
                lut_free(dn->u.stmt.lutp, instances_destructor, NULL);
                dn->u.stmt.lutp = NULL;
        }
        if (dn->t != T_FUNC)    /* T_FUNC pointed to original node */
                tree_free(dn);
}

/*ARGSUSED*/
static void
payloadprops_destructor(void *left, void *right, void *arg)
{
        FREE(right);
}

/*ARGSUSED*/
static void
serdprops_destructor(void *left, void *right, void *arg)
{
        FREE(right);
}

/*
 * event_cmp -- used via lut_lookup/lut_add on instance tree lut
 */
static int
event_cmp(struct event *ep1, struct event *ep2)
{
        int diff;

        if ((diff = ep2->enode->u.event.ename->u.name.s -
            ep1->enode->u.event.ename->u.name.s) != 0)
                return (diff);
        if ((diff = (char *)ep2->ipp - (char *)ep1->ipp) != 0)
                return (diff);
        return (0);

}

struct event *
itree_lookup(struct lut *itp, const char *ename, const struct ipath *ipp)
{
        struct event searchevent;       /* just used for searching */
        struct node searcheventnode;
        struct node searchenamenode;

        searchevent.enode = &searcheventnode;
        searcheventnode.t = T_EVENT;
        searcheventnode.u.event.ename = &searchenamenode;
        searchenamenode.t = T_NAME;
        searchenamenode.u.name.s = ename;
        searchevent.ipp = ipp;
        return (lut_lookup(itp, (void *)&searchevent, (lut_cmp)event_cmp));
}

static struct event *
find_or_add_event(struct info *infop, struct node *np)
{
        struct event *ret;
        struct event searchevent;       /* just used for searching */

        ASSERTeq(np->t, T_EVENT, ptree_nodetype2str);

        searchevent.enode = np;
        searchevent.ipp = ipath(np->u.event.epname);
        if ((ret = lut_lookup(infop->lut, (void *)&searchevent,
            (lut_cmp)event_cmp)) != NULL)
                return (ret);

        /* wasn't already in tree, allocate it */
        ret = alloc_xmalloc(sizeof (*ret));
        bzero(ret, sizeof (*ret));

        ret->t = np->u.event.ename->u.name.t;
        ret->enode = np;
        ret->ipp = searchevent.ipp;
        ret->props = props2instance(np, np->u.event.epname);

        infop->lut = lut_add(infop->lut, (void *)ret, (void *)ret,
            (lut_cmp)event_cmp);

        return (ret);
}

/*
 * Used for handling expansions where first part of oldepname is a horizontal
 * expansion. Recurses through entire tree. oldepname argument is always the
 * full path as in the rules. Once we find a match we go back to using
 * hmatch_event to handle the rest.
 */
static void
hmatch_full_config(struct info *infop, struct node *eventnp,
    struct node *oldepname, struct config *ncp, struct node *nextnp,
    struct iterinfo *iterinfop)
{
        char *cp_s;
        int cp_num;
        struct config *cp;
        struct node *saved_ewname;
        struct node *saved_epname;
        struct config *pcp, *ocp;
        struct node *cpnode;
        struct node *ewlp, *ewfp;

        for (cp = ncp; cp; cp = config_next(cp)) {
                config_getcompname(cp, &cp_s, &cp_num);
                if (cp_s == oldepname->u.name.s) {
                        /*
                         * Found one.
                         */
                        iterinfop->num = cp_num;

                        /*
                         * Need to set ewname, epname for correct node as is
                         * needed by constraint path matching. This code is
                         * similar to that in vmatch_event.
                         */
                        saved_ewname = eventnp->u.event.ewname;
                        saved_epname = eventnp->u.event.epname;
                        ocp = oldepname->u.name.cp;

                        /*
                         * Find correct ewname by walking back up the config
                         * tree adding each name portion as we go.
                         */
                        pcp = config_parent(cp);
                        eventnp->u.event.ewname = NULL;
                        for (; pcp != infop->croot; pcp = config_parent(pcp)) {
                                config_getcompname(pcp, &cp_s, &cp_num);
                                cpnode = tree_name(cp_s, IT_NONE, NULL, 0);
                                cpnode->u.name.child = newnode(T_NUM, NULL, 0);
                                cpnode->u.name.child->u.ull = cp_num;
                                cpnode->u.name.cp = pcp;
                                if (eventnp->u.event.ewname != NULL) {
                                        cpnode->u.name.next =
                                            eventnp->u.event.ewname;
                                        cpnode->u.name.last =
                                            eventnp->u.event.ewname->
                                            u.name.last;
                                }
                                eventnp->u.event.ewname = cpnode;
                        }

                        /*
                         * Now create correct epname by duping new ewname
                         * and appending oldepname.
                         */
                        ewfp = tname_dup(eventnp->u.event.ewname, CN_DUP);
                        ewlp = ewfp->u.name.last;
                        ewfp->u.name.last = oldepname->u.name.last;
                        ewlp->u.name.next = oldepname;
                        oldepname->u.name.cp = cp;
                        eventnp->u.event.epname = ewfp;

                        outfl(O_ALTFP|O_VERB3|O_NONL, infop->anp->file,
                            infop->anp->line, "hmatch_full_config: ");
                        ptree_name_iter(O_ALTFP|O_VERB3|O_NONL,
                            eventnp->u.event.epname);
                        out(O_ALTFP|O_VERB3, NULL);

                        /*
                         * Now complete hmatch.
                         */
                        hmatch_event(infop, eventnp, oldepname->u.name.next,
                            config_child(cp), nextnp, 1);

                        /*
                         * set everything back again
                         */
                        oldepname->u.name.cp = ocp;
                        iterinfop->num = -1;
                        ewlp->u.name.next = NULL;
                        ewfp->u.name.last = ewlp;
                        tree_free(ewfp);
                        tree_free(eventnp->u.event.ewname);
                        eventnp->u.event.ewname = saved_ewname;
                        eventnp->u.event.epname = saved_epname;
                }
                /*
                 * Try the next level down.
                 */
                hmatch_full_config(infop, eventnp,
                    oldepname, config_child(cp), nextnp, iterinfop);
        }
}

/*
 * hmatch_event -- perform any appropriate horizontal expansion on an event
 *
 * this routine is used to perform horizontal expansion on both the
 * left-hand-side events in a prop, and the right-hand-side events.
 * when called to handle a left-side event, nextnp point to the right
 * side of the prop that should be passed to hmatch() for each match
 * found by horizontal expansion.   when no horizontal expansion exists,
 * we will still "match" one event for every event found in the list on
 * the left-hand-side of the prop because vmatch() already found that
 * there's at least one match during vertical expansion.
 */
static void
hmatch_event(struct info *infop, struct node *eventnp, struct node *epname,
    struct config *ncp, struct node *nextnp, int rematch)
{
        if (epname == NULL) {
                /*
                 * end of pathname recursion, either we just located
                 * a left-hand-side event and we're ready to move on
                 * to the expanding the right-hand-side events, or
                 * we're further down the recursion and we just located
                 * a right-hand-side event.  the passed-in parameter
                 * "nextnp" tells us whether we're working on the left
                 * side and need to move on to nextnp, or if nextnp is
                 * NULL, we're working on the right side.
                 */
                if (nextnp) {
                        /*
                         * finished a left side expansion, move on to right.
                         * tell generate() what event we just matched so
                         * it can be used at the source of any arrows
                         * we generate as we match events on the right side.
                         */
                        generate_from(eventnp);
                        hmatch(infop, nextnp, NULL);
                } else {
                        /*
                         * finished a right side expansion.  tell generate
                         * the information about the destination and let
                         * it construct the arrows as appropriate.
                         */
                        generate_to(eventnp);
                        generate(infop);
                }

                return;
        }

        ASSERTeq(epname->t, T_NAME, ptree_nodetype2str);

        if (epname->u.name.cp == NULL)
                return;

        /*
         * we only get here when eventnp already has a completely
         * instanced epname in it already.  so we first recurse
         * down to the end of the name and as the recursion pops
         * up, we look for opportunities to advance horizontal
         * expansions on to the next match.
         */
        if (epname->u.name.it == IT_HORIZONTAL || rematch) {
                struct config *cp;
                struct config *ocp = epname->u.name.cp;
                char *cp_s;
                int cp_num;
                int ocp_num;
                struct iterinfo *iterinfop = NULL;
                const char *iters;
                int hexpand = 0;

                if (epname->u.name.it != IT_HORIZONTAL) {
                        /*
                         * Ancestor was horizontal though, so must rematch
                         * against the name/num found in vmatch.
                         */
                        config_getcompname(ocp, NULL, &ocp_num);
                } else {
                        iters = epname->u.name.child->u.name.s;
                        if ((iterinfop = lut_lookup(infop->ex,
                            (void *)iters, NULL)) == NULL) {
                                /*
                                 * do horizontal expansion on this node
                                 */
                                hexpand = 1;
                                iterinfop = alloc_xmalloc(
                                    sizeof (struct iterinfo));
                                iterinfop->num = -1;
                                iterinfop->np = epname;
                                infop->ex = lut_add(infop->ex, (void *)iters,
                                    iterinfop, NULL);
                        } else if (iterinfop->num == -1) {
                                hexpand = 1;
                        } else {
                                /*
                                 * This name has already been used in a
                                 * horizontal expansion. This time just match it
                                 */
                                ocp_num = iterinfop->num;
                        }
                }
                /*
                 * handle case where this is the first section of oldepname
                 * and it is horizontally expanded. Instead of just looking for
                 * siblings, we want to scan the entire config tree for further
                 * matches.
                 */
                if (epname == eventnp->u.event.oldepname &&
                    epname->u.name.it == IT_HORIZONTAL) {
                        /*
                         * Run through config looking for any that match the
                         * name.
                         */
                        hmatch_full_config(infop, eventnp, epname,
                            infop->croot, nextnp, iterinfop);
                        return;
                }

                /*
                 * Run through siblings looking for any that match the name.
                 * If hexpand not set then num must also match ocp_num.
                 */
                for (cp = rematch ? ncp : ocp; cp; cp = config_next(cp)) {
                        config_getcompname(cp, &cp_s, &cp_num);
                        if (cp_s == epname->u.name.s) {
                                if (hexpand)
                                        iterinfop->num = cp_num;
                                else if (ocp_num != cp_num)
                                        continue;
                                epname->u.name.cp = cp;
                                hmatch_event(infop, eventnp,
                                    epname->u.name.next, config_child(cp),
                                    nextnp, 1);
                        }
                }
                epname->u.name.cp = ocp;
                if (hexpand)
                        iterinfop->num = -1;
        } else {
                hmatch_event(infop, eventnp, epname->u.name.next,
                    NULL, nextnp, 0);
        }
}

/*
 * hmatch -- check for horizontal expansion matches
 *
 * np points to the things we're matching (like a T_LIST or a T_EVENT)
 * and if we're working on a left-side of a prop, nextnp points to
 * the other side of the prop that we'll tackle next when this recursion
 * bottoms out.  when all the events in the entire prop arrow have been
 * horizontally expanded, generate() will be called to generate the
 * actualy arrow.
 */
static void
hmatch(struct info *infop, struct node *np, struct node *nextnp)
{
        if (np == NULL)
                return;         /* all done */

        /*
         * for each item in the list of events (which could just
         * be a single event, or it could get larger in the loop
         * below due to horizontal expansion), call hmatch on
         * the right side and create arrows to each element.
         */

        switch (np->t) {
        case T_LIST:
                /* loop through the list */
                if (np->u.expr.left)
                        hmatch(infop, np->u.expr.left, nextnp);
                if (np->u.expr.right)
                        hmatch(infop, np->u.expr.right, nextnp);
                break;

        case T_EVENT:
                hmatch_event(infop, np, np->u.event.epname,
                    NULL, nextnp, 0);
                break;

        default:
                outfl(O_DIE, np->file, np->line,
                    "hmatch: unexpected type: %s",
                    ptree_nodetype2str(np->t));
        }
}

static int
itree_np2nork(struct node *norknp)
{
        if (norknp == NULL)
                return (1);
        else if (norknp->t == T_NAME && norknp->u.name.s == L_A)
                return (-1);    /* our internal version of "all" */
        else if (norknp->t == T_NUM)
                return ((int)norknp->u.ull);
        else
                outfl(O_DIE, norknp->file, norknp->line,
                    "itree_np2nork: internal error type %s",
                    ptree_nodetype2str(norknp->t));
        /*NOTREACHED*/
        return (1);
}

static struct iterinfo *
newiterinfo(int num, struct node *np)
{
        struct iterinfo *ret = alloc_xmalloc(sizeof (*ret));

        ret->num = num;
        ret->np = np;
        return (ret);
}

/*ARGSUSED*/
static void
iterinfo_destructor(void *left, void *right, void *arg)
{
        struct iterinfo *iterinfop = (struct iterinfo *)right;

        alloc_xfree(iterinfop, sizeof (*iterinfop));
}

static void
vmatch_event(struct info *infop, struct config *cp, struct node *np,
            struct node *lnp, struct node *anp, struct wildcardinfo *wcp)
{
        char *cp_s;
        int cp_num;
        struct node *ewlp, *ewfp;
        struct config *pcp;
        struct node *cpnode;
        int newewname = 0;

        /*
         * handle case where the first section of the path name is horizontally
         * expanded. The whole expansion is handled by hmatch on the first
         * match here - so we just skip any subsequent matches here.
         */
        if (wcp->got_wc_hz == 1)
                return;

        if (np == NULL) {
                /*
                 * Reached the end of the name. u.name.cp pointers should be set
                 * up for each part of name. From this we can use config tree
                 * to build up the wildcard part of the name (if any).
                 */
                pcp = config_parent(wcp->nptop->u.event.epname->u.name.cp);
                if (pcp == infop->croot) {
                        /*
                         * no wildcarding done - move on to next entry
                         */
                        wcp->nptop->u.event.ewname = wcp->ewname;
                        wcp->nptop->u.event.oldepname = wcp->oldepname;
                        vmatch(infop, np, lnp, anp);
                        wcp->got_wc_hz = 0;
                        return;
                }
                if (wcp->ewname == NULL) {
                        /*
                         * ewname not yet set up - do it now
                         */
                        newewname = 1;
                        for (; pcp != infop->croot; pcp = config_parent(pcp)) {
                                config_getcompname(pcp, &cp_s, &cp_num);
                                cpnode = tree_name(cp_s, IT_NONE, NULL, 0);
                                cpnode->u.name.child = newnode(T_NUM, NULL, 0);
                                cpnode->u.name.child->u.ull = cp_num;
                                cpnode->u.name.cp = pcp;
                                if (wcp->ewname != NULL) {
                                        cpnode->u.name.next = wcp->ewname;
                                        cpnode->u.name.last =
                                            wcp->ewname->u.name.last;
                                }
                                wcp->ewname = cpnode;
                        }
                }

                /*
                 * dup ewname and append oldepname
                 */
                ewfp = tname_dup(wcp->ewname, CN_DUP);
                ewlp = ewfp->u.name.last;
                ewfp->u.name.last = wcp->oldepname->u.name.last;
                ewlp->u.name.next = wcp->oldepname;

                wcp->nptop->u.event.epname = ewfp;
                wcp->nptop->u.event.ewname = wcp->ewname;
                wcp->nptop->u.event.oldepname = wcp->oldepname;
                vmatch(infop, np, lnp, anp);
                wcp->got_wc_hz = 0;
                wcp->nptop->u.event.epname = wcp->oldepname;

                /*
                 * reduce duped ewname to original then free
                 */
                ewlp->u.name.next = NULL;
                ewfp->u.name.last = ewlp;
                tree_free(ewfp);

                if (newewname) {
                        /*
                         * free ewname if allocated above
                         */
                        tree_free(wcp->ewname);
                        wcp->ewname = NULL;
                }
                return;
        }

        /*
         * We have an np. See if we can match it in this section of
         * the config tree.
         */
        if (cp == NULL)
                return; /* no more config to match against */

        for (; cp; cp = config_next(cp)) {
                config_getcompname(cp, &cp_s, &cp_num);

                if (cp_s == np->u.name.s) {
                        /* found a matching component name */
                        if (np->u.name.child &&
                            np->u.name.child->t == T_NUM) {
                                /*
                                 * an explicit instance number was given
                                 * in the source.  so only consider this
                                 * a configuration match if the number
                                 * also matches.
                                 */
                                if (cp_num != np->u.name.child->u.ull)
                                        continue;

                        } else if (np->u.name.it != IT_HORIZONTAL) {
                                struct iterinfo *iterinfop;
                                const char *iters;

                                /*
                                 * vertical iterator.  look it up in
                                 * the appropriate lut and if we get
                                 * back a value it is either one that we
                                 * set earlier, in which case we record
                                 * the new value for this iteration and
                                 * keep matching, or it is one that was
                                 * set by an earlier reference to the
                                 * iterator, in which case we only consider
                                 * this a configuration match if the number
                                 * matches cp_num.
                                 */

                                ASSERT(np->u.name.child != NULL);
                                ASSERT(np->u.name.child->t == T_NAME);
                                iters = np->u.name.child->u.name.s;

                                if ((iterinfop = lut_lookup(infop->ex,
                                    (void *)iters, NULL)) == NULL) {
                                        /* we're the first use, record our np */
                                        infop->ex = lut_add(infop->ex,
                                            (void *)iters,
                                            newiterinfo(cp_num, np), NULL);
                                } else if (np == iterinfop->np) {
                                        /*
                                         * we're the first use, back again
                                         * for another iteration.  so update
                                         * the num bound to this iterator in
                                         * the lut.
                                         */
                                        iterinfop->num = cp_num;
                                } else if (cp_num != iterinfop->num) {
                                        /*
                                         * an earlier reference to this
                                         * iterator bound it to a different
                                         * instance number, so there's no
                                         * match here after all.
                                         *
                                         * however, it's possible that this
                                         * component should really be part of
                                         * the wildcard.  we explore this by
                                         * forcing this component into the
                                         * wildcarded section.
                                         *
                                         * for an more details of what's
                                         * going to happen now, see
                                         * comments block below entitled
                                         * "forcing components into
                                         * wildcard path".
                                         */
                                        if (np == wcp->nptop->u.event.epname)
                                                vmatch_event(infop,
                                                    config_child(cp), np, lnp,
                                                    anp, wcp);
                                        continue;
                                }
                        }

                        /*
                         * if this was an IT_HORIZONTAL name, hmatch() will
                         * expand all matches horizontally into a list.
                         * we know the list will contain at least
                         * one element (the one we just matched),
                         * so we just let hmatch_event() do the rest.
                         *
                         * recurse on to next component. Note that
                         * wildcarding is now turned off.
                         */
                        np->u.name.cp = cp;
                        vmatch_event(infop, config_child(cp), np->u.name.next,
                            lnp, anp, wcp);
                        np->u.name.cp = NULL;

                        /*
                         * handle case where this is the first section of the
                         * path name and it is horizontally expanded.
                         * In this case we want all matching nodes in the config
                         * to be expanded horizontally - so set got_wc_hz and
                         * leave all further processing to hmatch.
                         */
                        if (G.matched && np == wcp->nptop->u.event.epname &&
                            np->u.name.it == IT_HORIZONTAL)
                                wcp->got_wc_hz = 1;

                        /*
                         * forcing components into wildcard path:
                         *
                         * if this component is the first match, force it
                         * to be part of the wildcarded path and see if we
                         * can get additional matches.
                         *
                         * here's an example.  suppose we have the
                         * definition
                         *      event foo@x/y
                         * and configuration
                         *      a0/x0/y0/a1/x1/y1
                         *
                         * the code up to this point will treat "a0" as the
                         * wildcarded part of the path and "x0/y0" as the
                         * nonwildcarded part, resulting in the instanced
                         * event
                         *      foo@a0/x0/y0
                         *
                         * in order to discover the next match (.../x1/y1)
                         * in the configuration we have to force "x0" into
                         * the wildcarded part of the path.
                         * by doing so, we discover the wildcarded part
                         * "a0/x0/y0/a1" and the nonwildcarded part "x1/y1"
                         *
                         * the following call to vmatch_event() is also
                         * needed to properly handle the configuration
                         *      b0/x0/b1/x1/y1
                         *
                         * the recursions into vmatch_event() will start
                         * off uncovering "b0" as the wildcarded part and
                         * "x0" as the start of the nonwildcarded path.
                         * however, the next recursion will not result in a
                         * match since there is no "y" following "x0".  the
                         * subsequent match of (wildcard = "b0/x0/b1" and
                         * nonwildcard = "x1/y1") will be discovered only
                         * if "x0" is forced to be a part of the wildcarded
                         * path.
                         */
                        if (np == wcp->nptop->u.event.epname)
                                vmatch_event(infop, config_child(cp), np, lnp,
                                    anp, wcp);

                        if (np->u.name.it == IT_HORIZONTAL) {
                                /*
                                 * hmatch() finished iterating through
                                 * the configuration as described above, so
                                 * don't continue iterating here.
                                 */
                                return;
                        }
                } else if (np == wcp->nptop->u.event.epname) {
                        /*
                         * no match - carry on down the tree looking for
                         * wildcarding
                         */
                        vmatch_event(infop, config_child(cp), np, lnp, anp,
                            wcp);
                }
        }
}

/*
 * vmatch -- find the next vertical expansion match in the config database
 *
 * this routine is called with three node pointers:
 *       np -- the parse we're matching
 *      lnp -- the rest of the list we're currently working on
 *      anp -- the rest of the arrow we're currently working on
 *
 * the expansion matching happens via three types of recursion:
 *
 *      - when given an arrow, handle the left-side and then recursively
 *        handle the right side (which might be another cascaded arrow).
 *
 *      - when handling one side of an arrow, recurse through the T_LIST
 *        to get to each event (or just move on to the event if there
 *        is a single event instead of a list)  since the arrow parse
 *        trees recurse left, we actually start with the right-most
 *        event list in the prop statement and work our way towards
 *        the left-most event list.
 *
 *      - when handling an event, recurse down each component of the
 *        pathname, matching in the config database and recording the
 *        matches in the explicit iterator dictionary as we go.
 *
 * when the bottom of this matching recursion is met, meaning we have
 * set the "cp" pointers on all the names in the entire statement,
 * we call hmatch() which does it's own recursion to handle horizontal
 * expandsion and then call generate() to generate nodes, bubbles, and
 * arrows in the instance tree.  generate() looks at the cp pointers to
 * see what instance numbers were matched in the configuration database.
 *
 * when horizontal expansion appears, vmatch() finds only the first match
 * and hmatch() then takes the horizontal expansion through all the other
 * matches when generating the arrows in the instance tree.
 *
 * the "infop" passed down through the recursion contains a dictionary
 * of the explicit iterators (all the implicit iterators have been converted
 * to explicit iterators when the parse tree was created by tree.c), which
 * allows things like this to work correctly:
 *
 *      prop error.a@x[n]/y/z -> error.b@x/y[n]/z -> error.c@x/y/z[n];
 *
 * during the top level call, the explicit iterator "n" will match an
 * instance number in the config database, and the result will be recorded
 * in the explicit iterator dictionary and passed down via "infop".  so
 * when the recursive call tries to match y[n] in the config database, it
 * will only match the same instance number as x[n] did since the dictionary
 * is consulted to see if "n" took on a value already.
 *
 * at any point during the recursion, match*() can return to indicate
 * a match was not found in the config database and that the caller should
 * move on to the next potential match, if any.
 *
 * constraints are completely ignored by match(), so the statement:
 *
 *      prop error.a@x[n] -> error.b@x[n] {n != 0};
 *
 * might very well match x[0] if it appears in the config database.  it
 * is the generate() routine that takes that match and then decides what
 * arrow, if any, should be generated in the instance tree.  generate()
 * looks at the explicit iterator dictionary to get values like "n" in
 * the above example so that it can evaluate constraints.
 *
 */
static void
vmatch(struct info *infop, struct node *np, struct node *lnp, struct node *anp)
{
        struct node *np1, *np2, *oldepname, *oldnptop;
        int epmatches;
        struct config *cp;
        struct wildcardinfo *wcp;

        if (np == NULL) {
                G.matched = 1;
                if (lnp)
                        vmatch(infop, lnp, NULL, anp);
                else if (anp)
                        vmatch(infop, anp, NULL, NULL);
                else {
                        struct node *src;
                        struct node *dst;

                        /* end of vertical match recursion */
                        outfl(O_ALTFP|O_VERB3|O_NONL,
                            infop->anp->file, infop->anp->line, "vmatch: ");
                        ptree_name_iter(O_ALTFP|O_VERB3|O_NONL, infop->anp);
                        out(O_ALTFP|O_VERB3, NULL);

                        generate_nork(
                            itree_np2nork(infop->anp->u.arrow.nnp),
                            itree_np2nork(infop->anp->u.arrow.knp));
                        dst = infop->anp->u.arrow.rhs;
                        src = infop->anp->u.arrow.lhs;
                        for (;;) {
                                generate_new(); /* new set of arrows */
                                if (src->t == T_ARROW) {
                                        hmatch(infop, src->u.arrow.rhs, dst);
                                        generate_nork(
                                            itree_np2nork(src->u.arrow.nnp),
                                            itree_np2nork(src->u.arrow.knp));
                                        dst = src->u.arrow.rhs;
                                        src = src->u.arrow.lhs;
                                } else {
                                        hmatch(infop, src, dst);
                                        break;
                                }
                        }
                }
                return;
        }

        switch (np->t) {
        case T_EVENT: {
                epmatches = 0;
                /*
                 * see if we already have a match in the wcps
                 */
                for (wcp = wcproot; wcp; wcp = wcp->next) {
                        oldepname = wcp->oldepname;
                        oldnptop = wcp->nptop;
                        for (np1 = oldepname, np2 = np->u.event.epname;
                            np1 != NULL && np2 != NULL; np1 = np1->u.name.next,
                            np2 = np2->u.name.next) {
                                if (strcmp(np1->u.name.s, np2->u.name.s) != 0)
                                        break;
                                if (np1->u.name.child->t !=
                                    np2->u.name.child->t)
                                        break;
                                if (np1->u.name.child->t == T_NUM &&
                                    np1->u.name.child->u.ull !=
                                    np2->u.name.child->u.ull)
                                        break;
                                if (np1->u.name.child->t == T_NAME &&
                                    strcmp(np1->u.name.child->u.name.s,
                                    np2->u.name.child->u.name.s) != 0)
                                        break;
                                epmatches++;
                        }
                        if (epmatches)
                                break;
                }
                if (epmatches && np1 == NULL && np2 == NULL) {
                        /*
                         * complete names match, can just borrow the fields
                         */
                        oldepname = np->u.event.epname;
                        np->u.event.epname = oldnptop->u.event.epname;
                        np->u.event.oldepname = wcp->oldepname;
                        np->u.event.ewname = wcp->ewname;
                        vmatch(infop, NULL, lnp, anp);
                        np->u.event.epname = oldepname;
                        return;
                }
                G.matched = 0;
                if (epmatches) {
                        /*
                         * just first part of names match - do wildcarding
                         * by using existing wcp including ewname and also
                         * copying as much of pwname as is valid, then start
                         * vmatch_event() at start of non-matching section
                         */
                        for (np1 = oldepname, np2 = np->u.event.epname;
                            epmatches != 0; epmatches--) {
                                cp = np1->u.name.cp;
                                np2->u.name.cp = cp;
                                np1 = np1->u.name.next;
                                np2 = np2->u.name.next;
                        }
                        wcp->oldepname = np->u.event.epname;
                        wcp->nptop = np;
                        vmatch_event(infop, config_child(cp), np2, lnp,
                            anp, wcp);
                        wcp->oldepname = oldepname;
                        wcp->nptop = oldnptop;
                        if (G.matched == 0) {
                                /*
                                 * This list entry is NULL. Move on to next item
                                 * in the list.
                                 */
                                vmatch(infop, NULL, lnp, anp);
                        }
                        return;
                }
                /*
                 * names do not match - allocate a new wcp
                 */
                wcp = MALLOC(sizeof (struct wildcardinfo));
                wcp->next = wcproot;
                wcproot = wcp;
                wcp->nptop = np;
                wcp->oldepname = np->u.event.epname;
                wcp->ewname = NULL;
                wcp->got_wc_hz = 0;

                vmatch_event(infop, config_child(infop->croot),
                    np->u.event.epname, lnp, anp, wcp);

                wcproot = wcp->next;
                FREE(wcp);
                if (G.matched == 0) {
                        /*
                         * This list entry is NULL. Move on to next item in the
                         * list.
                         */
                        vmatch(infop, NULL, lnp, anp);
                }
                break;
        }
        case T_LIST:
                ASSERT(lnp == NULL);
                vmatch(infop, np->u.expr.right, np->u.expr.left, anp);
                break;

        case T_ARROW:
                ASSERT(lnp == NULL && anp == NULL);
                vmatch(infop, np->u.arrow.rhs, NULL, np->u.arrow.parent);
                break;

        default:
                outfl(O_DIE, np->file, np->line,
                    "vmatch: unexpected type: %s",
                    ptree_nodetype2str(np->t));
        }
}

static void
find_first_arrow(struct info *infop, struct node *anp)
{
        if (anp->u.arrow.lhs->t == T_ARROW) {
                anp->u.arrow.lhs->u.arrow.parent = anp;
                find_first_arrow(infop, anp->u.arrow.lhs);
        } else
                vmatch(infop, anp->u.arrow.lhs, NULL, anp);
}

static void
cp_reset(struct node *np)
{
        if (np == NULL)
                return;
        switch (np->t) {
        case T_NAME:
                np->u.name.cp = NULL;
                cp_reset(np->u.name.next);
                break;

        case T_LIST:
                cp_reset(np->u.expr.left);
                cp_reset(np->u.expr.right);
                break;

        case T_ARROW:
                cp_reset(np->u.arrow.lhs);
                cp_reset(np->u.arrow.rhs);
                break;

        case T_EVENT:
                cp_reset(np->u.event.epname);
                break;
        }
}

/*
 * itree_create -- apply the current config to the current parse tree
 *
 * returns a lut mapping fully-instance-qualified names to struct events.
 *
 */
struct lut *
itree_create(struct config *croot)
{
        struct lut *retval;
        struct node *propnp;
        extern int alloc_total();
        int init_size;

        Ninfo.lut = NULL;
        Ninfo.croot = croot;
        init_size = alloc_total();
        out(O_ALTFP|O_STAMP, "start itree_create using %d bytes", init_size);
        for (propnp = Props; propnp; propnp = propnp->u.stmt.next) {
                struct node *anp = propnp->u.stmt.np;

                ASSERTeq(anp->t, T_ARROW, ptree_nodetype2str);

                if (!anp->u.arrow.needed)
                        continue;
                Ninfo.anp = anp;
                Ninfo.ex = NULL;

                generate_arrownp(anp);
                anp->u.arrow.parent = NULL;
                find_first_arrow(&Ninfo, anp);

                if (Ninfo.ex) {
                        lut_free(Ninfo.ex, iterinfo_destructor, NULL);
                        Ninfo.ex = NULL;
                }
                cp_reset(anp);
        }

        out(O_ALTFP|O_STAMP, "itree_create added %d bytes",
            alloc_total() - init_size);
        retval = Ninfo.lut;
        Ninfo.lut = NULL;
        return (retval);
}

/*
 * initial first pass of the rules.
 * We don't use the config at all. Just check the last part of the pathname
 * in the rules. If this matches the last part of the pathname in the first
 * ereport, then set pathname to the pathname in the ereport. If not then
 * set pathname to just the last part of pathname with instance number 0.
 * Constraints are ignored and all nork values are set to 0. If after all that
 * any rules can still not be associated with the ereport, then they are set
 * to not needed in prune_propagations() and ignored in the real itree_create()
 * which follows.
 */

static struct event *
add_event_dummy(struct node *np, const struct ipath *ipp)
{
        struct event *ret;
        struct event searchevent;       /* just used for searching */
        extern struct ipath *ipath_dummy(struct node *, struct ipath *);
        struct ipath *ipp_un;
        extern struct ipath *ipath_for_usednames(struct node *);

        searchevent.enode = np;
        searchevent.ipp = ipath_dummy(np->u.event.epname, (struct ipath *)ipp);
        ipp_un = ipath_for_usednames(np->u.event.epname);
        if ((ret = lut_lookup(Ninfo.lut, (void *)&searchevent,
            (lut_cmp)event_cmp)) != NULL)
                return (ret);

        ret = alloc_xmalloc(sizeof (*ret));
        bzero(ret, sizeof (*ret));
        ret->t = np->u.event.ename->u.name.t;
        ret->enode = np;
        ret->ipp = searchevent.ipp;
        ret->ipp_un = ipp_un;
        Ninfo.lut = lut_add(Ninfo.lut, (void *)ret, (void *)ret,
            (lut_cmp)event_cmp);
        return (ret);
}

/*ARGSUSED*/
struct lut *
itree_create_dummy(const char *e0class, const struct ipath *e0ipp)
{
        struct node *propnp;
        struct event *frome, *toe;
        struct bubble *frombp, *tobp;
        struct arrow *arrowp;
        struct node *src, *dst, *slst, *dlst, *arrownp, *oldarrownp;
        int gen = 0;
        extern int alloc_total();
        int init_size;

        Ninfo.lut = NULL;
        init_size = alloc_total();
        out(O_ALTFP|O_STAMP, "start itree_create using %d bytes", init_size);
        for (propnp = Props; propnp; propnp = propnp->u.stmt.next) {
                arrownp = propnp->u.stmt.np;
                while (arrownp) {
                        gen++;
                        dlst = arrownp->u.arrow.rhs;
                        slst = arrownp->u.arrow.lhs;
                        oldarrownp = arrownp;
                        if (slst->t == T_ARROW) {
                                arrownp = slst;
                                slst = slst->u.arrow.rhs;
                        } else {
                                arrownp = NULL;
                        }
                        while (slst) {
                                if (slst->t == T_LIST) {
                                        src = slst->u.expr.right;
                                        slst = slst->u.expr.left;
                                } else {
                                        src = slst;
                                        slst = NULL;
                                }
                                frome = add_event_dummy(src, e0ipp);
                                frombp = itree_add_bubble(frome, B_FROM, 0, 0);
                                while (dlst) {
                                        if (dlst->t == T_LIST) {
                                                dst = dlst->u.expr.right;
                                                dlst = dlst->u.expr.left;
                                        } else {
                                                dst = dlst;
                                                dlst = NULL;
                                        }
                                        arrowp = alloc_xmalloc(
                                            sizeof (struct arrow));
                                        bzero(arrowp, sizeof (struct arrow));
                                        arrowp->pnode = oldarrownp;
                                        toe = add_event_dummy(dst, e0ipp);
                                        tobp = itree_add_bubble(toe, B_TO, 0,
                                            gen);
                                        arrowp->tail = frombp;
                                        arrowp->head = tobp;
                                        add_arrow(frombp, arrowp);
                                        add_arrow(tobp, arrowp);
                                        arrow_add_within(arrowp,
                                            dst->u.event.declp->u.stmt.np->
                                            u.event.eexprlist);
                                        arrow_add_within(arrowp,
                                            dst->u.event.eexprlist);
                                }
                        }
                }
        }
        out(O_ALTFP|O_STAMP, "itree_create added %d bytes",
            alloc_total() - init_size);
        return (Ninfo.lut);
}

void
itree_free(struct lut *lutp)
{
        int init_size;

        init_size = alloc_total();
        out(O_ALTFP|O_STAMP, "start itree_free");
        lut_free(lutp, itree_destructor, NULL);
        out(O_ALTFP|O_STAMP, "itree_free freed %d bytes",
            init_size - alloc_total());
}

void
itree_prune(struct lut *lutp)
{
        int init_size;

        init_size = alloc_total();
        out(O_ALTFP|O_STAMP, "start itree_prune");
        lut_walk(lutp, itree_pruner, NULL);
        out(O_ALTFP|O_STAMP, "itree_prune freed %d bytes",
            init_size - alloc_total());
}

void
itree_pevent_brief(int flags, struct event *ep)
{
        ASSERT(ep != NULL);
        ASSERT(ep->enode != NULL);
        ASSERT(ep->ipp != NULL);

        ipath_print(flags, ep->enode->u.event.ename->u.name.s, ep->ipp);
}

/*ARGSUSED*/
static void
itree_pevent(struct event *lhs, struct event *ep, void *arg)
{
        struct plut_wlk_data propd;
        struct bubble *bp;
        int flags = (int)(intptr_t)arg;

        itree_pevent_brief(flags, ep);
        if (ep->t == N_EREPORT)
                out(flags, " (count %d)", ep->count);
        else
                out(flags, NULL);

        if (ep->props) {
                propd.flags = flags;
                propd.first = 1;
                out(flags, "Properties:");
                lut_walk(ep->props, ptree_plut, (void *)&propd);
        }

        for (bp = itree_next_bubble(ep, NULL); bp;
            bp = itree_next_bubble(ep, bp)) {
                /* Print only TO bubbles in this loop */
                if (bp->t != B_TO)
                        continue;
                itree_pbubble(flags, bp);
        }

        for (bp = itree_next_bubble(ep, NULL); bp;
            bp = itree_next_bubble(ep, bp)) {
                /* Print only INHIBIT bubbles in this loop */
                if (bp->t != B_INHIBIT)
                        continue;
                itree_pbubble(flags, bp);
        }

        for (bp = itree_next_bubble(ep, NULL); bp;
            bp = itree_next_bubble(ep, bp)) {
                /* Print only FROM bubbles in this loop */
                if (bp->t != B_FROM)
                        continue;
                itree_pbubble(flags, bp);
        }
}

static void
itree_pbubble(int flags, struct bubble *bp)
{
        struct constraintlist *cp;
        struct arrowlist *ap;

        ASSERT(bp != NULL);

        out(flags|O_NONL, "   ");
        if (bp->mark)
                out(flags|O_NONL, "*");
        else
                out(flags|O_NONL, " ");
        if (bp->t == B_FROM)
                out(flags|O_NONL, "N=%d to:", bp->nork);
        else if (bp->t == B_TO)
                out(flags|O_NONL, "K=%d from:", bp->nork);
        else
                out(flags|O_NONL, "K=%d masked from:", bp->nork);

        if (bp->t == B_TO || bp->t == B_INHIBIT) {
                for (ap = itree_next_arrow(bp, NULL); ap;
                    ap = itree_next_arrow(bp, ap)) {
                        ASSERT(ap->arrowp->head == bp);
                        ASSERT(ap->arrowp->tail != NULL);
                        ASSERT(ap->arrowp->tail->myevent != NULL);
                        out(flags|O_NONL, " ");
                        itree_pevent_brief(flags, ap->arrowp->tail->myevent);
                }
                out(flags, NULL);
                return;
        }

        for (ap = itree_next_arrow(bp, NULL); ap;
            ap = itree_next_arrow(bp, ap)) {
                ASSERT(ap->arrowp->tail == bp);
                ASSERT(ap->arrowp->head != NULL);
                ASSERT(ap->arrowp->head->myevent != NULL);

                out(flags|O_NONL, " ");
                itree_pevent_brief(flags, ap->arrowp->head->myevent);

                out(flags|O_NONL, " ");
                ptree_timeval(flags, &ap->arrowp->mindelay);
                out(flags|O_NONL, ",");
                ptree_timeval(flags, &ap->arrowp->maxdelay);

                /* Display anything from the propogation node? */
                out(O_VERB3|O_NONL, " <%s:%d>",
                    ap->arrowp->pnode->file, ap->arrowp->pnode->line);

                if (itree_next_constraint(ap->arrowp, NULL))
                        out(flags|O_NONL, " {");

                for (cp = itree_next_constraint(ap->arrowp, NULL); cp;
                    cp = itree_next_constraint(ap->arrowp, cp)) {
                        ptree(flags, cp->cnode, 1, 0);
                        if (itree_next_constraint(ap->arrowp, cp))
                                out(flags|O_NONL, ", ");
                }

                if (itree_next_constraint(ap->arrowp, NULL))
                        out(flags|O_NONL, "}");
        }
        out(flags, NULL);
}

void
itree_ptree(int flags, struct lut *itp)
{
        lut_walk(itp, (lut_cb)itree_pevent, (void *)(intptr_t)flags);
}

/*ARGSUSED*/
static void
itree_destructor(void *left, void *right, void *arg)
{
        struct event *ep = (struct event *)right;
        struct bubble *nextbub, *bub;

        /* Free the properties */
        if (ep->props)
                lut_free(ep->props, instances_destructor, NULL);

        /* Free the payload properties */
        if (ep->payloadprops)
                lut_free(ep->payloadprops, payloadprops_destructor, NULL);

        /* Free the serd properties */
        if (ep->serdprops)
                lut_free(ep->serdprops, serdprops_destructor, NULL);

        /* Free my bubbles */
        for (bub = ep->bubbles; bub != NULL; ) {
                nextbub = bub->next;
                /*
                 * Free arrows if they are FROM me.  Free arrowlists on
                 * other types of bubbles (but not the attached arrows,
                 * which will be freed when we free the originating
                 * bubble.
                 */
                if (bub->t == B_FROM)
                        itree_free_arrowlists(bub, 1);
                else
                        itree_free_arrowlists(bub, 0);
                itree_free_bubble(bub);
                bub = nextbub;
        }

        nvlist_free(ep->nvp);
        alloc_xfree(ep, sizeof (*ep));
}

/*ARGSUSED*/
static void
itree_pruner(void *left, void *right, void *arg)
{
        struct event *ep = (struct event *)right;
        struct bubble *nextbub, *bub;

        if (ep->keep_in_tree)
                return;

        /* Free the properties */
        lut_free(ep->props, instances_destructor, NULL);

        /* Free the payload properties */
        lut_free(ep->payloadprops, payloadprops_destructor, NULL);

        /* Free the serd properties */
        lut_free(ep->serdprops, serdprops_destructor, NULL);

        /* Free my bubbles */
        for (bub = ep->bubbles; bub != NULL; ) {
                nextbub = bub->next;
                itree_prune_arrowlists(bub);
                itree_free_bubble(bub);
                bub = nextbub;
        }

        nvlist_free(ep->nvp);
        ep->props = NULL;
        ep->payloadprops = NULL;
        ep->serdprops = NULL;
        ep->bubbles = NULL;
        ep->nvp = NULL;
}

static void
itree_free_bubble(struct bubble *freeme)
{
        alloc_xfree(freeme, sizeof (*freeme));
}

static struct bubble *
itree_add_bubble(struct event *eventp, enum bubbletype btype, int nork, int gen)
{
        struct bubble *prev = NULL;
        struct bubble *curr;
        struct bubble *newb;

        /* Use existing bubbles as appropriate when possible */
        for (curr = eventp->bubbles;
            curr != NULL;
            prev = curr, curr = curr->next) {
                if (btype == B_TO && curr->t == B_TO) {
                        /* see if an existing "to" bubble works for us */
                        if (gen == curr->gen)
                                return (curr);  /* matched gen number */
                        else if (nork == 1 && curr->nork == 1) {
                                curr->gen = gen;
                                return (curr);  /* coalesce K==1 bubbles */
                        }
                } else if (btype == B_FROM && curr->t == B_FROM) {
                        /* see if an existing "from" bubble works for us */
                        if ((nork == N_IS_ALL && curr->nork == N_IS_ALL) ||
                            (nork == 0 && curr->nork == 0))
                                return (curr);
                }
        }

        newb = alloc_xmalloc(sizeof (struct bubble));
        newb->next = NULL;
        newb->t = btype;
        newb->myevent = eventp;
        newb->nork = nork;
        newb->mark = 0;
        newb->gen = gen;
        newb->arrows = NULL;

        if (prev == NULL)
                eventp->bubbles = newb;
        else
                prev->next = newb;

        return (newb);
}

struct bubble *
itree_next_bubble(struct event *eventp, struct bubble *last)
{
        struct bubble *next;

        for (;;) {
                if (last != NULL)
                        next = last->next;
                else
                        next = eventp->bubbles;

                if (next == NULL || next->arrows != NULL)
                        return (next);

                /* bubble was empty, skip it */
                last = next;
        }
}

static void
add_arrow(struct bubble *bp, struct arrow *ap)
{
        struct arrowlist *prev = NULL;
        struct arrowlist *curr;
        struct arrowlist *newal;

        newal = alloc_xmalloc(sizeof (struct arrowlist));
        bzero(newal, sizeof (struct arrowlist));
        newal->arrowp = ap;

        curr = itree_next_arrow(bp, NULL);
        while (curr != NULL) {
                prev = curr;
                curr = itree_next_arrow(bp, curr);
        }

        if (prev == NULL)
                bp->arrows = newal;
        else
                prev->next = newal;
}

static struct arrow *
itree_add_arrow(struct node *apnode, struct node *fromevent,
    struct node *toevent, struct lut *ex)
{
        struct arrow *newa;

        newa = alloc_xmalloc(sizeof (struct arrow));
        bzero(newa, sizeof (struct arrow));
        newa->pnode = apnode;
        newa->constraints = NULL;

        /*
         *  Set default delays, then try to re-set them from
         *  any within() constraints.
         */
        newa->mindelay = newa->maxdelay = 0ULL;
        if (itree_set_arrow_traits(newa, fromevent, toevent, ex) == 0) {
                alloc_xfree(newa, sizeof (struct arrow));
                return (NULL);
        }

        return (newa);
}

/* returns false if traits show that arrow should not be added after all */
static int
itree_set_arrow_traits(struct arrow *ap, struct node *fromev,
    struct node *toev, struct lut *ex)
{
        struct node *events[] = { NULL, NULL, NULL };
        struct node *newc = NULL;

        ASSERTeq(fromev->t, T_EVENT, ptree_nodetype2str);
        ASSERTeq(toev->t, T_EVENT, ptree_nodetype2str);

        /*
         * search for the within values first on the declaration of
         * the destination event, and then on the prop.  this allows
         * one to specify a "default" within by putting it on the
         * declaration,  but then allow overriding on the prop statement.
         */
        arrow_add_within(ap, toev->u.event.declp->u.stmt.np->u.event.eexprlist);
        arrow_add_within(ap, toev->u.event.eexprlist);

        /*
         * handle any global constraints inherited from the
         * "fromev" event's declaration
         */
        ASSERT(fromev->u.event.declp != NULL);
        ASSERT(fromev->u.event.declp->u.stmt.np != NULL);

#ifdef  notdef
        /* XXX not quite ready to evaluate constraints from decls yet */
        if (fromev->u.event.declp->u.stmt.np->u.event.eexprlist)
                (void) itree_add_constraint(ap,
                    fromev->u.event.declp->u.stmt.np->u.event.eexprlist);
#endif  /* notdef */

        /* handle constraints on the from event in the prop statement */
        events[0] = fromev;
        events[1] = toev;
        if (eval_potential(fromev->u.event.eexprlist, ex, events, &newc,
            Ninfo.croot) == 0)
                return (0);             /* constraint disallows arrow */

        /*
         * handle any global constraints inherited from the
         * "toev" event's declaration
         */
        ASSERT(toev->u.event.declp != NULL);
        ASSERT(toev->u.event.declp->u.stmt.np != NULL);

#ifdef  notdef
        /* XXX not quite ready to evaluate constraints from decls yet */
        if (toev->u.event.declp->u.stmt.np->u.event.eexprlist)
                (void) itree_add_constraint(ap,
                    toev->u.event.declp->u.stmt.np->u.event.eexprlist);
#endif  /* notdef */

        /* handle constraints on the to event in the prop statement */
        events[0] = toev;
        events[1] = fromev;
        if (eval_potential(toev->u.event.eexprlist, ex, events, &newc,
            Ninfo.croot) == 0) {
                if (newc != NULL)
                        tree_free(newc);
                return (0);             /* constraint disallows arrow */
        }

        /* if we came up with any deferred constraints, add them to arrow */
        if (newc != NULL) {
                out(O_ALTFP|O_VERB3, "(deferred constraints)");
                (void) itree_add_constraint(ap, iexpr(newc));
        }

        return (1);     /* constraints allow arrow */
}

/*
 * Set within() constraint.  If the constraint were set multiple times,
 * the last one would "win".
 */
static void
arrow_add_within(struct arrow *ap, struct node *xpr)
{
        struct node *arglist;

        /* end of expressions list */
        if (xpr == NULL)
                return;

        switch (xpr->t) {
        case T_LIST:
                arrow_add_within(ap, xpr->u.expr.left);
                arrow_add_within(ap, xpr->u.expr.right);
                return;
        case T_FUNC:
                if (xpr->u.func.s != L_within)
                        return;
                arglist = xpr->u.func.arglist;
                switch (arglist->t) {
                case T_TIMEVAL:
                        ap->mindelay = 0;
                        ap->maxdelay = arglist->u.ull;
                        break;
                case T_NAME:
                        ASSERT(arglist->u.name.s == L_infinity);
                        ap->mindelay = 0;
                        ap->maxdelay = TIMEVAL_EVENTUALLY;
                        break;
                case T_LIST:
                        ASSERT(arglist->u.expr.left->t == T_TIMEVAL);
                        ap->mindelay = arglist->u.expr.left->u.ull;
                        switch (arglist->u.expr.right->t) {
                        case T_TIMEVAL:
                                ap->maxdelay = arglist->u.ull;
                                break;
                        case T_NAME:
                                ASSERT(arglist->u.expr.right->u.name.s ==
                                    L_infinity);
                                ap->maxdelay = TIMEVAL_EVENTUALLY;
                                break;
                        default:
                                out(O_DIE, "within: unexpected 2nd arg type");
                        }
                        break;
                default:
                        out(O_DIE, "within: unexpected 1st arg type");
                }
                break;
        default:
                return;
        }
}

static void
itree_free_arrowlists(struct bubble *bubp, int arrows_too)
{
        struct arrowlist *al, *nal;

        al = bubp->arrows;
        while (al != NULL) {
                nal = al->next;
                if (arrows_too) {
                        itree_free_constraints(al->arrowp);
                        alloc_xfree(al->arrowp, sizeof (struct arrow));
                }
                alloc_xfree(al, sizeof (*al));
                al = nal;
        }
}

static void
itree_delete_arrow(struct bubble *bubp, struct arrow *arrow)
{
        struct arrowlist *al, *oal;

        al = bubp->arrows;
        if (al->arrowp == arrow) {
                bubp->arrows = al->next;
                alloc_xfree(al, sizeof (*al));
                return;
        }
        while (al != NULL) {
                oal = al;
                al = al->next;
                ASSERT(al != NULL);
                if (al->arrowp == arrow) {
                        oal->next = al->next;
                        alloc_xfree(al, sizeof (*al));
                        return;
                }
        }
}

static void
itree_prune_arrowlists(struct bubble *bubp)
{
        struct arrowlist *al, *nal;

        al = bubp->arrows;
        while (al != NULL) {
                nal = al->next;
                if (bubp->t == B_FROM)
                        itree_delete_arrow(al->arrowp->head, al->arrowp);
                else
                        itree_delete_arrow(al->arrowp->tail, al->arrowp);
                itree_free_constraints(al->arrowp);
                alloc_xfree(al->arrowp, sizeof (struct arrow));
                alloc_xfree(al, sizeof (*al));
                al = nal;
        }
}

struct arrowlist *
itree_next_arrow(struct bubble *bubble, struct arrowlist *last)
{
        struct arrowlist *next;

        if (last != NULL)
                next = last->next;
        else
                next = bubble->arrows;
        return (next);
}

static struct constraintlist *
itree_add_constraint(struct arrow *arrowp, struct node *c)
{
        struct constraintlist *prev = NULL;
        struct constraintlist *curr;
        struct constraintlist *newc;

        for (curr = arrowp->constraints;
            curr != NULL;
            prev = curr, curr = curr->next)
                ;

        newc = alloc_xmalloc(sizeof (struct constraintlist));
        newc->next = NULL;
        newc->cnode = c;

        if (prev == NULL)
                arrowp->constraints = newc;
        else
                prev->next = newc;

        return (newc);
}

struct constraintlist *
itree_next_constraint(struct arrow *arrowp, struct constraintlist *last)
{
        struct constraintlist *next;

        if (last != NULL)
                next = last->next;
        else
                next = arrowp->constraints;
        return (next);
}

static void
itree_free_constraints(struct arrow *ap)
{
        struct constraintlist *cl, *ncl;

        cl = ap->constraints;
        while (cl != NULL) {
                ncl = cl->next;
                ASSERT(cl->cnode != NULL);
                if (!iexpr_cached(cl->cnode))
                        tree_free(cl->cnode);
                else
                        iexpr_free(cl->cnode);
                alloc_xfree(cl, sizeof (*cl));
                cl = ncl;
        }
}

const char *
itree_bubbletype2str(enum bubbletype t)
{
        static char buf[100];

        switch (t) {
        case B_FROM:    return L_from;
        case B_TO:      return L_to;
        case B_INHIBIT: return L_inhibit;
        default:
                (void) sprintf(buf, "[unexpected bubbletype: %d]", t);
                return (buf);
        }
}

/*
 * itree_fini -- clean up any half-built itrees
 */
void
itree_fini(void)
{
        if (Ninfo.lut != NULL) {
                itree_free(Ninfo.lut);
                Ninfo.lut = NULL;
        }
        if (Ninfo.ex) {
                lut_free(Ninfo.ex, iterinfo_destructor, NULL);
                Ninfo.ex = NULL;
        }
}