2 * Copyright (c) 1988, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 * must display the following acknowledgement:
15 * This product includes software developed by the University of
16 * California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * @(#)radix.c 8.4 (Berkeley) 11/2/94
34 * $FreeBSD: src/sys/net/radix.c,v 1.20.2.3 2002/04/28 05:40:25 suz Exp $
35 * $DragonFly: src/sys/net/radix.c,v 1.5 2003/08/26 20:49:47 rob Exp $
39 * Routines to build and maintain radix trees for routing lookups.
42 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/malloc.h>
46 #include <sys/domain.h>
50 #include <sys/syslog.h>
51 #include <net/radix.h>
54 static int rn_walktree_from (struct radix_node_head *h, void *a,
55 void *m, walktree_f_t *f, void *w);
56 static int rn_walktree (struct radix_node_head *, walktree_f_t *, void *);
57 static struct radix_node
58 *rn_insert (void *, struct radix_node_head *, int *,
59 struct radix_node [2]),
60 *rn_newpair (void *, int, struct radix_node[2]),
61 *rn_search (void *, struct radix_node *),
62 *rn_search_m (void *, struct radix_node *, void *);
64 static int max_keylen;
65 static struct radix_mask *rn_mkfreelist;
66 static struct radix_node_head *mask_rnhead;
67 static char *addmask_key;
68 static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1};
69 static char *rn_zeros, *rn_ones;
71 #define rn_masktop (mask_rnhead->rnh_treetop)
73 #define Bcmp(a, b, l) \
74 (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l))
76 static int rn_lexobetter (void *m_arg, void *n_arg);
77 static struct radix_mask *
78 rn_new_radix_mask (struct radix_node *tt,
79 struct radix_mask *next);
80 static int rn_satsifies_leaf (char *trial, struct radix_node *leaf,
84 * The data structure for the keys is a radix tree with one way
85 * branching removed. The index rn_bit at an internal node n represents a bit
86 * position to be tested. The tree is arranged so that all descendants
87 * of a node n have keys whose bits all agree up to position rn_bit - 1.
88 * (We say the index of n is rn_bit.)
90 * There is at least one descendant which has a one bit at position rn_bit,
91 * and at least one with a zero there.
93 * A route is determined by a pair of key and mask. We require that the
94 * bit-wise logical and of the key and mask to be the key.
95 * We define the index of a route to associated with the mask to be
96 * the first bit number in the mask where 0 occurs (with bit number 0
97 * representing the highest order bit).
99 * We say a mask is normal if every bit is 0, past the index of the mask.
100 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_bit,
101 * and m is a normal mask, then the route applies to every descendant of n.
102 * If the index(m) < rn_bit, this implies the trailing last few bits of k
103 * before bit b are all 0, (and hence consequently true of every descendant
104 * of n), so the route applies to all descendants of the node as well.
106 * Similar logic shows that a non-normal mask m such that
107 * index(m) <= index(n) could potentially apply to many children of n.
108 * Thus, for each non-host route, we attach its mask to a list at an internal
109 * node as high in the tree as we can go.
111 * The present version of the code makes use of normal routes in short-
112 * circuiting an explict mask and compare operation when testing whether
113 * a key satisfies a normal route, and also in remembering the unique leaf
114 * that governs a subtree.
117 static struct radix_node *
118 rn_search(v_arg, head)
120 struct radix_node *head;
122 struct radix_node *x;
125 for (x = head, v = v_arg; x->rn_bit >= 0;) {
126 if (x->rn_bmask & v[x->rn_offset])
134 static struct radix_node *
135 rn_search_m(v_arg, head, m_arg)
136 struct radix_node *head;
139 struct radix_node *x;
140 caddr_t v = v_arg, m = m_arg;
142 for (x = head; x->rn_bit >= 0;) {
143 if ((x->rn_bmask & m[x->rn_offset]) &&
144 (x->rn_bmask & v[x->rn_offset]))
153 rn_refines(m_arg, n_arg)
156 caddr_t m = m_arg, n = n_arg;
157 caddr_t lim, lim2 = lim = n + *(u_char *)n;
158 int longer = (*(u_char *)n++) - (int)(*(u_char *)m++);
159 int masks_are_equal = 1;
172 if (masks_are_equal && (longer < 0))
173 for (lim2 = m - longer; m < lim2; )
176 return (!masks_are_equal);
180 rn_lookup(v_arg, m_arg, head)
182 struct radix_node_head *head;
184 struct radix_node *x;
188 x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_offset);
193 x = rn_match(v_arg, head);
195 while (x && x->rn_mask != netmask)
202 rn_satsifies_leaf(trial, leaf, skip)
204 struct radix_node *leaf;
207 char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask;
209 int length = min(*(u_char *)cp, *(u_char *)cp2);
214 length = min(length, *(u_char *)cp3);
215 cplim = cp + length; cp3 += skip; cp2 += skip;
216 for (cp += skip; cp < cplim; cp++, cp2++, cp3++)
217 if ((*cp ^ *cp2) & *cp3)
223 rn_match(v_arg, head)
225 struct radix_node_head *head;
228 struct radix_node *t = head->rnh_treetop, *x;
231 struct radix_node *saved_t, *top = t;
232 int off = t->rn_offset, vlen = *(u_char *)cp, matched_off;
236 * Open code rn_search(v, top) to avoid overhead of extra
239 for (; t->rn_bit >= 0; ) {
240 if (t->rn_bmask & cp[t->rn_offset])
246 * See if we match exactly as a host destination
247 * or at least learn how many bits match, for normal mask finesse.
249 * It doesn't hurt us to limit how many bytes to check
250 * to the length of the mask, since if it matches we had a genuine
251 * match and the leaf we have is the most specific one anyway;
252 * if it didn't match with a shorter length it would fail
253 * with a long one. This wins big for class B&C netmasks which
254 * are probably the most common case...
257 vlen = *(u_char *)t->rn_mask;
258 cp += off; cp2 = t->rn_key + off; cplim = v + vlen;
259 for (; cp < cplim; cp++, cp2++)
263 * This extra grot is in case we are explicitly asked
264 * to look up the default. Ugh!
266 * Never return the root node itself, it seems to cause a
269 if (t->rn_flags & RNF_ROOT)
273 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */
274 for (b = 7; (test >>= 1) > 0;)
276 matched_off = cp - v;
277 b += matched_off << 3;
280 * If there is a host route in a duped-key chain, it will be first.
282 if ((saved_t = t)->rn_mask == 0)
284 for (; t; t = t->rn_dupedkey)
286 * Even if we don't match exactly as a host,
287 * we may match if the leaf we wound up at is
290 if (t->rn_flags & RNF_NORMAL) {
291 if (rn_bit <= t->rn_bit)
293 } else if (rn_satsifies_leaf(v, t, matched_off))
296 /* start searching up the tree */
298 struct radix_mask *m;
302 * If non-contiguous masks ever become important
303 * we can restore the masking and open coding of
304 * the search and satisfaction test and put the
305 * calculation of "off" back before the "do".
308 if (m->rm_flags & RNF_NORMAL) {
309 if (rn_bit <= m->rm_bit)
312 off = min(t->rn_offset, matched_off);
313 x = rn_search_m(v, t, m->rm_mask);
314 while (x && x->rn_mask != m->rm_mask)
316 if (x && rn_satsifies_leaf(v, x, off))
327 struct radix_node *rn_clist;
332 static struct radix_node *
333 rn_newpair(v, b, nodes)
336 struct radix_node nodes[2];
338 struct radix_node *tt = nodes, *t = tt + 1;
340 t->rn_bmask = 0x80 >> (b & 7);
342 t->rn_offset = b >> 3;
344 tt->rn_key = (caddr_t)v;
346 tt->rn_flags = t->rn_flags = RNF_ACTIVE;
347 tt->rn_mklist = t->rn_mklist = 0;
349 tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
351 tt->rn_ybro = rn_clist;
357 static struct radix_node *
358 rn_insert(v_arg, head, dupentry, nodes)
360 struct radix_node_head *head;
362 struct radix_node nodes[2];
365 struct radix_node *top = head->rnh_treetop;
366 int head_off = top->rn_offset, vlen = (int)*((u_char *)v);
367 struct radix_node *t = rn_search(v_arg, top);
368 caddr_t cp = v + head_off;
370 struct radix_node *tt;
372 * Find first bit at which v and t->rn_key differ
375 caddr_t cp2 = t->rn_key + head_off;
377 caddr_t cplim = v + vlen;
386 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff;
387 for (b = (cp - v) << 3; cmp_res; b--)
391 struct radix_node *p, *x = top;
395 if (cp[x->rn_offset] & x->rn_bmask)
399 } while (b > (unsigned) x->rn_bit);
400 /* x->rn_bit < b && x->rn_bit >= 0 */
403 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p);
405 t = rn_newpair(v_arg, b, nodes);
407 if ((cp[p->rn_offset] & p->rn_bmask) == 0)
412 t->rn_parent = p; /* frees x, p as temp vars below */
413 if ((cp[t->rn_offset] & t->rn_bmask) == 0) {
421 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p);
428 rn_addmask(n_arg, search, skip)
432 caddr_t netmask = (caddr_t)n_arg;
433 struct radix_node *x;
436 int maskduplicated, m0, isnormal;
437 struct radix_node *saved_x;
438 static int last_zeroed = 0;
440 if ((mlen = *(u_char *)netmask) > max_keylen)
445 return (mask_rnhead->rnh_nodes);
447 Bcopy(rn_ones + 1, addmask_key + 1, skip - 1);
448 if ((m0 = mlen) > skip)
449 Bcopy(netmask + skip, addmask_key + skip, mlen - skip);
451 * Trim trailing zeroes.
453 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;)
455 mlen = cp - addmask_key;
457 if (m0 >= last_zeroed)
459 return (mask_rnhead->rnh_nodes);
461 if (m0 < last_zeroed)
462 Bzero(addmask_key + m0, last_zeroed - m0);
463 *addmask_key = last_zeroed = mlen;
464 x = rn_search(addmask_key, rn_masktop);
465 if (Bcmp(addmask_key, x->rn_key, mlen) != 0)
469 R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x));
470 if ((saved_x = x) == 0)
472 Bzero(x, max_keylen + 2 * sizeof (*x));
473 netmask = cp = (caddr_t)(x + 2);
474 Bcopy(addmask_key, cp, mlen);
475 x = rn_insert(cp, mask_rnhead, &maskduplicated, x);
476 if (maskduplicated) {
477 log(LOG_ERR, "rn_addmask: mask impossibly already in tree");
482 * Calculate index of mask, and check for normalcy.
484 cplim = netmask + mlen; isnormal = 1;
485 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;)
488 for (j = 0x80; (j & *cp) != 0; j >>= 1)
490 if (*cp != normal_chars[b] || cp != (cplim - 1))
493 b += (cp - netmask) << 3;
496 x->rn_flags |= RNF_NORMAL;
500 static int /* XXX: arbitrary ordering for non-contiguous masks */
501 rn_lexobetter(m_arg, n_arg)
504 u_char *mp = m_arg, *np = n_arg, *lim;
507 return 1; /* not really, but need to check longer one first */
509 for (lim = mp + *mp; mp < lim;)
515 static struct radix_mask *
516 rn_new_radix_mask(tt, next)
517 struct radix_node *tt;
518 struct radix_mask *next;
520 struct radix_mask *m;
524 log(LOG_ERR, "Mask for route not entered\n");
528 m->rm_bit = tt->rn_bit;
529 m->rm_flags = tt->rn_flags;
530 if (tt->rn_flags & RNF_NORMAL)
533 m->rm_mask = tt->rn_mask;
540 rn_addroute(v_arg, n_arg, head, treenodes)
542 struct radix_node_head *head;
543 struct radix_node treenodes[2];
545 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg;
546 struct radix_node *t, *x = 0, *tt;
547 struct radix_node *saved_tt, *top = head->rnh_treetop;
548 short b = 0, b_leaf = 0;
551 struct radix_mask *m, **mp;
554 * In dealing with non-contiguous masks, there may be
555 * many different routes which have the same mask.
556 * We will find it useful to have a unique pointer to
557 * the mask to speed avoiding duplicate references at
558 * nodes and possibly save time in calculating indices.
561 if ((x = rn_addmask(netmask, 0, top->rn_offset)) == 0)
568 * Deal with duplicated keys: attach node to previous instance
570 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes);
572 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) {
573 if (tt->rn_mask == netmask)
577 ((b_leaf < tt->rn_bit) /* index(netmask) > node */
578 || rn_refines(netmask, tt->rn_mask)
579 || rn_lexobetter(netmask, tt->rn_mask))))
583 * If the mask is not duplicated, we wouldn't
584 * find it among possible duplicate key entries
585 * anyway, so the above test doesn't hurt.
587 * We sort the masks for a duplicated key the same way as
588 * in a masklist -- most specific to least specific.
589 * This may require the unfortunate nuisance of relocating
590 * the head of the list.
592 if (tt == saved_tt) {
593 struct radix_node *xx = x;
594 /* link in at head of list */
595 (tt = treenodes)->rn_dupedkey = t;
596 tt->rn_flags = t->rn_flags;
597 tt->rn_parent = x = t->rn_parent;
598 t->rn_parent = tt; /* parent */
603 saved_tt = tt; x = xx;
605 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey;
607 tt->rn_parent = t; /* parent */
608 if (tt->rn_dupedkey) /* parent */
609 tt->rn_dupedkey->rn_parent = tt; /* parent */
612 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
613 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt;
615 tt->rn_key = (caddr_t) v;
617 tt->rn_flags = RNF_ACTIVE;
623 tt->rn_mask = netmask;
624 tt->rn_bit = x->rn_bit;
625 tt->rn_flags |= x->rn_flags & RNF_NORMAL;
627 t = saved_tt->rn_parent;
630 b_leaf = -1 - t->rn_bit;
631 if (t->rn_right == saved_tt)
635 /* Promote general routes from below */
637 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey)
638 if (x->rn_mask && (x->rn_bit >= b_leaf) && x->rn_mklist == 0) {
639 *mp = m = rn_new_radix_mask(x, 0);
643 } else if (x->rn_mklist) {
645 * Skip over masks whose index is > that of new node
647 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
648 if (m->rm_bit >= b_leaf)
650 t->rn_mklist = m; *mp = 0;
653 /* Add new route to highest possible ancestor's list */
654 if ((netmask == 0) || (b > t->rn_bit ))
655 return tt; /* can't lift at all */
660 } while (b <= t->rn_bit && x != top);
662 * Search through routes associated with node to
663 * insert new route according to index.
664 * Need same criteria as when sorting dupedkeys to avoid
665 * double loop on deletion.
667 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) {
668 if (m->rm_bit < b_leaf)
670 if (m->rm_bit > b_leaf)
672 if (m->rm_flags & RNF_NORMAL) {
673 mmask = m->rm_leaf->rn_mask;
674 if (tt->rn_flags & RNF_NORMAL) {
676 "Non-unique normal route, mask not entered\n");
681 if (mmask == netmask) {
686 if (rn_refines(netmask, mmask)
687 || rn_lexobetter(netmask, mmask))
690 *mp = rn_new_radix_mask(tt, *mp);
695 rn_delete(v_arg, netmask_arg, head)
696 void *v_arg, *netmask_arg;
697 struct radix_node_head *head;
699 struct radix_node *t, *p, *x, *tt;
700 struct radix_mask *m, *saved_m, **mp;
701 struct radix_node *dupedkey, *saved_tt, *top;
703 int b, head_off, vlen;
706 netmask = netmask_arg;
707 x = head->rnh_treetop;
708 tt = rn_search(v, x);
709 head_off = x->rn_offset;
714 Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off))
717 * Delete our route from mask lists.
720 if ((x = rn_addmask(netmask, 1, head_off)) == 0)
723 while (tt->rn_mask != netmask)
724 if ((tt = tt->rn_dupedkey) == 0)
727 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0)
729 if (tt->rn_flags & RNF_NORMAL) {
730 if (m->rm_leaf != tt || m->rm_refs > 0) {
731 log(LOG_ERR, "rn_delete: inconsistent annotation\n");
732 return 0; /* dangling ref could cause disaster */
735 if (m->rm_mask != tt->rn_mask) {
736 log(LOG_ERR, "rn_delete: inconsistent annotation\n");
739 if (--m->rm_refs >= 0)
743 t = saved_tt->rn_parent;
745 goto on1; /* Wasn't lifted at all */
749 } while (b <= t->rn_bit && x != top);
750 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
757 log(LOG_ERR, "rn_delete: couldn't find our annotation\n");
758 if (tt->rn_flags & RNF_NORMAL)
759 return (0); /* Dangling ref to us */
763 * Eliminate us from tree
765 if (tt->rn_flags & RNF_ROOT)
768 /* Get us out of the creation list */
769 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {}
770 if (t) t->rn_ybro = tt->rn_ybro;
773 dupedkey = saved_tt->rn_dupedkey;
776 * at this point, tt is the deletion target and saved_tt
777 * is the head of the dupekey chain
779 if (tt == saved_tt) {
780 /* remove from head of chain */
781 x = dupedkey; x->rn_parent = t;
782 if (t->rn_left == tt)
787 /* find node in front of tt on the chain */
788 for (x = p = saved_tt; p && p->rn_dupedkey != tt;)
791 p->rn_dupedkey = tt->rn_dupedkey;
792 if (tt->rn_dupedkey) /* parent */
793 tt->rn_dupedkey->rn_parent = p;
795 } else log(LOG_ERR, "rn_delete: couldn't find us\n");
798 if (t->rn_flags & RNF_ACTIVE) {
812 x->rn_left->rn_parent = x;
813 x->rn_right->rn_parent = x;
817 if (t->rn_left == tt)
822 if (p->rn_right == t)
828 * Demote routes attached to us.
831 if (x->rn_bit >= 0) {
832 for (mp = &x->rn_mklist; (m = *mp);)
836 /* If there are any key,mask pairs in a sibling
837 duped-key chain, some subset will appear sorted
838 in the same order attached to our mklist */
839 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey)
840 if (m == x->rn_mklist) {
841 struct radix_mask *mm = m->rm_mklist;
843 if (--(m->rm_refs) < 0)
849 "rn_delete: Orphaned Mask %p at %p\n",
850 (void *)m, (void *)x);
854 * We may be holding an active internal node in the tree.
865 t->rn_left->rn_parent = t;
866 t->rn_right->rn_parent = t;
874 tt->rn_flags &= ~RNF_ACTIVE;
875 tt[1].rn_flags &= ~RNF_ACTIVE;
880 * This is the same as rn_walktree() except for the parameters and the
884 rn_walktree_from(h, a, m, f, w)
885 struct radix_node_head *h;
891 struct radix_node *base, *next;
892 u_char *xa = (u_char *)a;
893 u_char *xm = (u_char *)m;
894 struct radix_node *rn, *last = 0 /* shut up gcc */;
899 * rn_search_m is sort-of-open-coded here.
901 /* printf("about to search\n"); */
902 for (rn = h->rnh_treetop; rn->rn_bit >= 0; ) {
904 /* printf("rn_bit %d, rn_bmask %x, xm[rn_offset] %x\n",
905 rn->rn_bit, rn->rn_bmask, xm[rn->rn_offset]); */
906 if (!(rn->rn_bmask & xm[rn->rn_offset])) {
909 if (rn->rn_bmask & xa[rn->rn_offset]) {
915 /* printf("done searching\n"); */
918 * Two cases: either we stepped off the end of our mask,
919 * in which case last == rn, or we reached a leaf, in which
920 * case we want to start from the last node we looked at.
921 * Either way, last is the node we want to start from.
926 /* printf("rn %p, lastb %d\n", rn, lastb);*/
929 * This gets complicated because we may delete the node
930 * while applying the function f to it, so we need to calculate
931 * the successor node in advance.
933 while (rn->rn_bit >= 0)
937 /* printf("node %p (%d)\n", rn, rn->rn_bit); */
939 /* If at right child go back up, otherwise, go right */
940 while (rn->rn_parent->rn_right == rn
941 && !(rn->rn_flags & RNF_ROOT)) {
944 /* if went up beyond last, stop */
945 if (rn->rn_bit < lastb) {
947 /* printf("up too far\n"); */
951 /* Find the next *leaf* since next node might vanish, too */
952 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;)
956 while ((rn = base) != 0) {
957 base = rn->rn_dupedkey;
958 /* printf("leaf %p\n", rn); */
959 if (!(rn->rn_flags & RNF_ROOT)
960 && (error = (*f)(rn, w)))
965 if (rn->rn_flags & RNF_ROOT) {
966 /* printf("root, stopping"); */
976 struct radix_node_head *h;
981 struct radix_node *base, *next;
982 struct radix_node *rn = h->rnh_treetop;
984 * This gets complicated because we may delete the node
985 * while applying the function f to it, so we need to calculate
986 * the successor node in advance.
988 /* First time through node, go left */
989 while (rn->rn_bit >= 0)
993 /* If at right child go back up, otherwise, go right */
994 while (rn->rn_parent->rn_right == rn
995 && (rn->rn_flags & RNF_ROOT) == 0)
997 /* Find the next *leaf* since next node might vanish, too */
998 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;)
1001 /* Process leaves */
1002 while ((rn = base)) {
1003 base = rn->rn_dupedkey;
1004 if (!(rn->rn_flags & RNF_ROOT)
1005 && (error = (*f)(rn, w)))
1009 if (rn->rn_flags & RNF_ROOT)
1016 rn_inithead(head, off)
1020 struct radix_node_head *rnh;
1021 struct radix_node *t, *tt, *ttt;
1024 R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh));
1027 Bzero(rnh, sizeof (*rnh));
1029 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes);
1030 ttt = rnh->rnh_nodes + 2;
1034 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE;
1035 tt->rn_bit = -1 - off;
1037 ttt->rn_key = rn_ones;
1038 rnh->rnh_addaddr = rn_addroute;
1039 rnh->rnh_deladdr = rn_delete;
1040 rnh->rnh_matchaddr = rn_match;
1041 rnh->rnh_lookup = rn_lookup;
1042 rnh->rnh_walktree = rn_walktree;
1043 rnh->rnh_walktree_from = rn_walktree_from;
1044 rnh->rnh_treetop = t;
1055 for (dom = domains; dom; dom = dom->dom_next)
1056 if (dom->dom_maxrtkey > max_keylen)
1057 max_keylen = dom->dom_maxrtkey;
1059 if (max_keylen == 0) {
1061 "rn_init: radix functions require max_keylen be set\n");
1064 R_Malloc(rn_zeros, char *, 3 * max_keylen);
1065 if (rn_zeros == NULL)
1067 Bzero(rn_zeros, 3 * max_keylen);
1068 rn_ones = cp = rn_zeros + max_keylen;
1069 addmask_key = cplim = rn_ones + max_keylen;
1072 if (rn_inithead((void **)&mask_rnhead, 0) == 0)