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 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * @(#)radix.c 8.5 (Berkeley) 5/19/95
30 * $FreeBSD: head/sys/net/radix.c 186176 2008-12-16 11:01:36Z kmacy $
35 * Routines to build and maintain radix trees for routing lookups.
38 #include <sys/param.h>
41 #include <sys/mutex.h>
42 #include <sys/rwlock.h>
43 #include <sys/systm.h>
44 #include <sys/malloc.h>
45 // #include <sys/domain.h>
49 #include <sys/syslog.h>
50 #include <net/radix.h>
53 // #include "opt_mpath.h"
56 #include <net/radix_mpath.h>
60 static int rn_walktree_from(struct radix_node_head *h, void *a, void *m,
61 walktree_f_t *f, void *w);
62 static int rn_walktree(struct radix_node_head *, walktree_f_t *, void *);
63 static struct radix_node
64 *rn_insert(void *, struct radix_node_head *, int *,
65 struct radix_node [2]),
66 *rn_newpair(void *, int, struct radix_node[2]),
67 *rn_search(void *, struct radix_node *),
68 *rn_search_m(void *, struct radix_node *, void *);
70 static int max_keylen;
71 static struct radix_mask *rn_mkfreelist;
72 static struct radix_node_head *mask_rnhead;
74 * Work area -- the following point to 3 buffers of size max_keylen,
75 * allocated in this order in a block of memory malloc'ed by rn_init.
77 static char *rn_zeros, *rn_ones, *addmask_key;
80 if (rn_mkfreelist) { \
82 rn_mkfreelist = (m)->rm_mklist; \
84 R_Malloc(m, struct radix_mask *, sizeof (struct radix_mask)); }
86 #define MKFree(m) { (m)->rm_mklist = rn_mkfreelist; rn_mkfreelist = (m);}
88 #define rn_masktop (mask_rnhead->rnh_treetop)
90 static int rn_lexobetter(void *m_arg, void *n_arg);
91 static struct radix_mask *
92 rn_new_radix_mask(struct radix_node *tt,
93 struct radix_mask *next);
94 static int rn_satisfies_leaf(char *trial, struct radix_node *leaf,
98 * The data structure for the keys is a radix tree with one way
99 * branching removed. The index rn_bit at an internal node n represents a bit
100 * position to be tested. The tree is arranged so that all descendants
101 * of a node n have keys whose bits all agree up to position rn_bit - 1.
102 * (We say the index of n is rn_bit.)
104 * There is at least one descendant which has a one bit at position rn_bit,
105 * and at least one with a zero there.
107 * A route is determined by a pair of key and mask. We require that the
108 * bit-wise logical and of the key and mask to be the key.
109 * We define the index of a route to associated with the mask to be
110 * the first bit number in the mask where 0 occurs (with bit number 0
111 * representing the highest order bit).
113 * We say a mask is normal if every bit is 0, past the index of the mask.
114 * If a node n has a descendant (k, m) with index(m) == index(n) == rn_bit,
115 * and m is a normal mask, then the route applies to every descendant of n.
116 * If the index(m) < rn_bit, this implies the trailing last few bits of k
117 * before bit b are all 0, (and hence consequently true of every descendant
118 * of n), so the route applies to all descendants of the node as well.
120 * Similar logic shows that a non-normal mask m such that
121 * index(m) <= index(n) could potentially apply to many children of n.
122 * Thus, for each non-host route, we attach its mask to a list at an internal
123 * node as high in the tree as we can go.
125 * The present version of the code makes use of normal routes in short-
126 * circuiting an explict mask and compare operation when testing whether
127 * a key satisfies a normal route, and also in remembering the unique leaf
128 * that governs a subtree.
132 * Most of the functions in this code assume that the key/mask arguments
133 * are sockaddr-like structures, where the first byte is an u_char
134 * indicating the size of the entire structure.
136 * To make the assumption more explicit, we use the LEN() macro to access
137 * this field. It is safe to pass an expression with side effects
138 * to LEN() as the argument is evaluated only once.
140 #define LEN(x) (*(const u_char *)(x))
143 * XXX THIS NEEDS TO BE FIXED
144 * In the code, pointers to keys and masks are passed as either
145 * 'void *' (because callers use to pass pointers of various kinds), or
146 * 'caddr_t' (which is fine for pointer arithmetics, but not very
147 * clean when you dereference it to access data). Furthermore, caddr_t
148 * is really 'char *', while the natural type to operate on keys and
149 * masks would be 'u_char'. This mismatch require a lot of casts and
150 * intermediate variables to adapt types that clutter the code.
154 * Search a node in the tree matching the key.
156 static struct radix_node *
157 rn_search(v_arg, head)
159 struct radix_node *head;
161 register struct radix_node *x;
164 for (x = head, v = v_arg; x->rn_bit >= 0;) {
165 if (x->rn_bmask & v[x->rn_offset])
174 * Same as above, but with an additional mask.
175 * XXX note this function is used only once.
177 static struct radix_node *
178 rn_search_m(v_arg, head, m_arg)
179 struct radix_node *head;
182 register struct radix_node *x;
183 register caddr_t v = v_arg, m = m_arg;
185 for (x = head; x->rn_bit >= 0;) {
186 if ((x->rn_bmask & m[x->rn_offset]) &&
187 (x->rn_bmask & v[x->rn_offset]))
196 rn_refines(m_arg, n_arg)
199 register caddr_t m = m_arg, n = n_arg;
200 register caddr_t lim, lim2 = lim = n + LEN(n);
201 int longer = LEN(n++) - (int)LEN(m++);
202 int masks_are_equal = 1;
215 if (masks_are_equal && (longer < 0))
216 for (lim2 = m - longer; m < lim2; )
219 return (!masks_are_equal);
223 rn_lookup(v_arg, m_arg, head)
225 struct radix_node_head *head;
227 register struct radix_node *x;
231 x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_offset);
236 x = rn_match(v_arg, head);
238 while (x && x->rn_mask != netmask)
245 rn_satisfies_leaf(trial, leaf, skip)
247 register struct radix_node *leaf;
250 register char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask;
252 int length = min(LEN(cp), LEN(cp2));
257 length = min(length, (int)(*(u_char *)cp3));
258 cplim = cp + length; cp3 += skip; cp2 += skip;
259 for (cp += skip; cp < cplim; cp++, cp2++, cp3++)
260 if ((*cp ^ *cp2) & *cp3)
266 rn_match(v_arg, head)
268 struct radix_node_head *head;
271 register struct radix_node *t = head->rnh_treetop, *x;
272 register caddr_t cp = v, cp2;
274 struct radix_node *saved_t, *top = t;
275 int off = t->rn_offset, vlen = LEN(cp), matched_off;
276 register int test, b, rn_bit;
279 * Open code rn_search(v, top) to avoid overhead of extra
282 for (; t->rn_bit >= 0; ) {
283 if (t->rn_bmask & cp[t->rn_offset])
289 * See if we match exactly as a host destination
290 * or at least learn how many bits match, for normal mask finesse.
292 * It doesn't hurt us to limit how many bytes to check
293 * to the length of the mask, since if it matches we had a genuine
294 * match and the leaf we have is the most specific one anyway;
295 * if it didn't match with a shorter length it would fail
296 * with a long one. This wins big for class B&C netmasks which
297 * are probably the most common case...
300 vlen = *(u_char *)t->rn_mask;
301 cp += off; cp2 = t->rn_key + off; cplim = v + vlen;
302 for (; cp < cplim; cp++, cp2++)
306 * This extra grot is in case we are explicitly asked
307 * to look up the default. Ugh!
309 * Never return the root node itself, it seems to cause a
312 if (t->rn_flags & RNF_ROOT)
316 test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */
317 for (b = 7; (test >>= 1) > 0;)
319 matched_off = cp - v;
320 b += matched_off << 3;
323 * If there is a host route in a duped-key chain, it will be first.
325 if ((saved_t = t)->rn_mask == 0)
327 for (; t; t = t->rn_dupedkey)
329 * Even if we don't match exactly as a host,
330 * we may match if the leaf we wound up at is
333 if (t->rn_flags & RNF_NORMAL) {
334 if (rn_bit <= t->rn_bit)
336 } else if (rn_satisfies_leaf(v, t, matched_off))
339 /* start searching up the tree */
341 register struct radix_mask *m;
345 * If non-contiguous masks ever become important
346 * we can restore the masking and open coding of
347 * the search and satisfaction test and put the
348 * calculation of "off" back before the "do".
351 if (m->rm_flags & RNF_NORMAL) {
352 if (rn_bit <= m->rm_bit)
355 off = min(t->rn_offset, matched_off);
356 x = rn_search_m(v, t, m->rm_mask);
357 while (x && x->rn_mask != m->rm_mask)
359 if (x && rn_satisfies_leaf(v, x, off))
370 struct radix_node *rn_clist;
376 * Whenever we add a new leaf to the tree, we also add a parent node,
377 * so we allocate them as an array of two elements: the first one must be
378 * the leaf (see RNTORT() in route.c), the second one is the parent.
379 * This routine initializes the relevant fields of the nodes, so that
380 * the leaf is the left child of the parent node, and both nodes have
381 * (almost) all all fields filled as appropriate.
382 * (XXX some fields are left unset, see the '#if 0' section).
383 * The function returns a pointer to the parent node.
386 static struct radix_node *
387 rn_newpair(v, b, nodes)
390 struct radix_node nodes[2];
392 register struct radix_node *tt = nodes, *t = tt + 1;
394 t->rn_bmask = 0x80 >> (b & 7);
396 t->rn_offset = b >> 3;
398 #if 0 /* XXX perhaps we should fill these fields as well. */
399 t->rn_parent = t->rn_right = NULL;
402 tt->rn_dupedkey = NULL;
406 tt->rn_key = (caddr_t)v;
408 tt->rn_flags = t->rn_flags = RNF_ACTIVE;
409 tt->rn_mklist = t->rn_mklist = 0;
411 tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
413 tt->rn_ybro = rn_clist;
419 static struct radix_node *
420 rn_insert(v_arg, head, dupentry, nodes)
422 struct radix_node_head *head;
424 struct radix_node nodes[2];
427 struct radix_node *top = head->rnh_treetop;
428 int head_off = top->rn_offset, vlen = (int)LEN(v);
429 register struct radix_node *t = rn_search(v_arg, top);
430 register caddr_t cp = v + head_off;
432 struct radix_node *tt;
434 * Find first bit at which v and t->rn_key differ
437 register caddr_t cp2 = t->rn_key + head_off;
438 register int cmp_res;
439 caddr_t cplim = v + vlen;
448 cmp_res = (cp[-1] ^ cp2[-1]) & 0xff;
449 for (b = (cp - v) << 3; cmp_res; b--)
453 register struct radix_node *p, *x = top;
457 if (cp[x->rn_offset] & x->rn_bmask)
461 } while (b > (unsigned) x->rn_bit);
462 /* x->rn_bit < b && x->rn_bit >= 0 */
465 log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p);
467 t = rn_newpair(v_arg, b, nodes);
469 if ((cp[p->rn_offset] & p->rn_bmask) == 0)
474 t->rn_parent = p; /* frees x, p as temp vars below */
475 if ((cp[t->rn_offset] & t->rn_bmask) == 0) {
483 log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p);
490 rn_addmask(n_arg, search, skip)
494 caddr_t netmask = (caddr_t)n_arg;
495 register struct radix_node *x;
496 register caddr_t cp, cplim;
497 register int b = 0, mlen, j;
498 int maskduplicated, m0, isnormal;
499 struct radix_node *saved_x;
500 static int last_zeroed = 0;
502 if ((mlen = LEN(netmask)) > max_keylen)
507 return (mask_rnhead->rnh_nodes);
509 bcopy(rn_ones + 1, addmask_key + 1, skip - 1);
510 if ((m0 = mlen) > skip)
511 bcopy(netmask + skip, addmask_key + skip, mlen - skip);
513 * Trim trailing zeroes.
515 for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;)
517 mlen = cp - addmask_key;
519 if (m0 >= last_zeroed)
521 return (mask_rnhead->rnh_nodes);
523 if (m0 < last_zeroed)
524 bzero(addmask_key + m0, last_zeroed - m0);
525 *addmask_key = last_zeroed = mlen;
526 x = rn_search(addmask_key, rn_masktop);
527 if (bcmp(addmask_key, x->rn_key, mlen) != 0)
531 R_Zalloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x));
532 if ((saved_x = x) == 0)
534 netmask = cp = (caddr_t)(x + 2);
535 bcopy(addmask_key, cp, mlen);
536 x = rn_insert(cp, mask_rnhead, &maskduplicated, x);
537 if (maskduplicated) {
538 log(LOG_ERR, "rn_addmask: mask impossibly already in tree");
543 * Calculate index of mask, and check for normalcy.
544 * First find the first byte with a 0 bit, then if there are
545 * more bits left (remember we already trimmed the trailing 0's),
546 * the pattern must be one of those in normal_chars[], or we have
547 * a non-contiguous mask.
549 cplim = netmask + mlen;
551 for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;)
554 static char normal_chars[] = {
555 0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, 0xff};
557 for (j = 0x80; (j & *cp) != 0; j >>= 1)
559 if (*cp != normal_chars[b] || cp != (cplim - 1))
562 b += (cp - netmask) << 3;
565 x->rn_flags |= RNF_NORMAL;
569 static int /* XXX: arbitrary ordering for non-contiguous masks */
570 rn_lexobetter(m_arg, n_arg)
573 register u_char *mp = m_arg, *np = n_arg, *lim;
575 if (LEN(mp) > LEN(np))
576 return 1; /* not really, but need to check longer one first */
577 if (LEN(mp) == LEN(np))
578 for (lim = mp + LEN(mp); mp < lim;)
584 static struct radix_mask *
585 rn_new_radix_mask(tt, next)
586 register struct radix_node *tt;
587 register struct radix_mask *next;
589 register struct radix_mask *m;
593 log(LOG_ERR, "Mask for route not entered\n");
597 m->rm_bit = tt->rn_bit;
598 m->rm_flags = tt->rn_flags;
599 if (tt->rn_flags & RNF_NORMAL)
602 m->rm_mask = tt->rn_mask;
609 rn_addroute(v_arg, n_arg, head, treenodes)
611 struct radix_node_head *head;
612 struct radix_node treenodes[2];
614 caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg;
615 register struct radix_node *t, *x = 0, *tt;
616 struct radix_node *saved_tt, *top = head->rnh_treetop;
617 short b = 0, b_leaf = 0;
620 struct radix_mask *m, **mp;
623 * In dealing with non-contiguous masks, there may be
624 * many different routes which have the same mask.
625 * We will find it useful to have a unique pointer to
626 * the mask to speed avoiding duplicate references at
627 * nodes and possibly save time in calculating indices.
630 if ((x = rn_addmask(netmask, 0, top->rn_offset)) == 0)
637 * Deal with duplicated keys: attach node to previous instance
639 saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes);
641 for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) {
643 /* permit multipath, if enabled for the family */
644 if (rn_mpath_capable(head) && netmask == tt->rn_mask) {
646 * go down to the end of multipaths, so that
647 * new entry goes into the end of rn_dupedkey
652 tt = tt->rn_dupedkey;
653 } while (tt && t->rn_mask == tt->rn_mask);
657 if (tt->rn_mask == netmask)
661 ((b_leaf < tt->rn_bit) /* index(netmask) > node */
662 || rn_refines(netmask, tt->rn_mask)
663 || rn_lexobetter(netmask, tt->rn_mask))))
667 * If the mask is not duplicated, we wouldn't
668 * find it among possible duplicate key entries
669 * anyway, so the above test doesn't hurt.
671 * We sort the masks for a duplicated key the same way as
672 * in a masklist -- most specific to least specific.
673 * This may require the unfortunate nuisance of relocating
674 * the head of the list.
676 * We also reverse, or doubly link the list through the
679 if (tt == saved_tt) {
680 struct radix_node *xx = x;
681 /* link in at head of list */
682 (tt = treenodes)->rn_dupedkey = t;
683 tt->rn_flags = t->rn_flags;
684 tt->rn_parent = x = t->rn_parent;
685 t->rn_parent = tt; /* parent */
690 saved_tt = tt; x = xx;
692 (tt = treenodes)->rn_dupedkey = t->rn_dupedkey;
694 tt->rn_parent = t; /* parent */
695 if (tt->rn_dupedkey) /* parent */
696 tt->rn_dupedkey->rn_parent = tt; /* parent */
699 t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++;
700 tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt;
702 tt->rn_key = (caddr_t) v;
704 tt->rn_flags = RNF_ACTIVE;
710 tt->rn_mask = netmask;
711 tt->rn_bit = x->rn_bit;
712 tt->rn_flags |= x->rn_flags & RNF_NORMAL;
714 t = saved_tt->rn_parent;
717 b_leaf = -1 - t->rn_bit;
718 if (t->rn_right == saved_tt)
722 /* Promote general routes from below */
724 for (mp = &t->rn_mklist; x; x = x->rn_dupedkey)
725 if (x->rn_mask && (x->rn_bit >= b_leaf) && x->rn_mklist == 0) {
726 *mp = m = rn_new_radix_mask(x, 0);
730 } else if (x->rn_mklist) {
732 * Skip over masks whose index is > that of new node
734 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
735 if (m->rm_bit >= b_leaf)
737 t->rn_mklist = m; *mp = 0;
740 /* Add new route to highest possible ancestor's list */
741 if ((netmask == 0) || (b > t->rn_bit ))
742 return tt; /* can't lift at all */
747 } while (b <= t->rn_bit && x != top);
749 * Search through routes associated with node to
750 * insert new route according to index.
751 * Need same criteria as when sorting dupedkeys to avoid
752 * double loop on deletion.
754 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) {
755 if (m->rm_bit < b_leaf)
757 if (m->rm_bit > b_leaf)
759 if (m->rm_flags & RNF_NORMAL) {
760 mmask = m->rm_leaf->rn_mask;
761 if (tt->rn_flags & RNF_NORMAL) {
763 "Non-unique normal route, mask not entered\n");
768 if (mmask == netmask) {
773 if (rn_refines(netmask, mmask)
774 || rn_lexobetter(netmask, mmask))
777 *mp = rn_new_radix_mask(tt, *mp);
782 rn_delete(v_arg, netmask_arg, head)
783 void *v_arg, *netmask_arg;
784 struct radix_node_head *head;
786 register struct radix_node *t, *p, *x, *tt;
787 struct radix_mask *m, *saved_m, **mp;
788 struct radix_node *dupedkey, *saved_tt, *top;
790 int b, head_off, vlen;
793 netmask = netmask_arg;
794 x = head->rnh_treetop;
795 tt = rn_search(v, x);
796 head_off = x->rn_offset;
801 bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off))
804 * Delete our route from mask lists.
807 if ((x = rn_addmask(netmask, 1, head_off)) == 0)
810 while (tt->rn_mask != netmask)
811 if ((tt = tt->rn_dupedkey) == 0)
814 if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0)
816 if (tt->rn_flags & RNF_NORMAL) {
817 if (m->rm_leaf != tt || m->rm_refs > 0) {
818 log(LOG_ERR, "rn_delete: inconsistent annotation\n");
819 return 0; /* dangling ref could cause disaster */
822 if (m->rm_mask != tt->rn_mask) {
823 log(LOG_ERR, "rn_delete: inconsistent annotation\n");
826 if (--m->rm_refs >= 0)
830 t = saved_tt->rn_parent;
832 goto on1; /* Wasn't lifted at all */
836 } while (b <= t->rn_bit && x != top);
837 for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist)
844 log(LOG_ERR, "rn_delete: couldn't find our annotation\n");
845 if (tt->rn_flags & RNF_NORMAL)
846 return (0); /* Dangling ref to us */
850 * Eliminate us from tree
852 if (tt->rn_flags & RNF_ROOT)
855 /* Get us out of the creation list */
856 for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {}
857 if (t) t->rn_ybro = tt->rn_ybro;
860 dupedkey = saved_tt->rn_dupedkey;
863 * Here, tt is the deletion target and
864 * saved_tt is the head of the dupekey chain.
866 if (tt == saved_tt) {
867 /* remove from head of chain */
868 x = dupedkey; x->rn_parent = t;
869 if (t->rn_left == tt)
874 /* find node in front of tt on the chain */
875 for (x = p = saved_tt; p && p->rn_dupedkey != tt;)
878 p->rn_dupedkey = tt->rn_dupedkey;
879 if (tt->rn_dupedkey) /* parent */
880 tt->rn_dupedkey->rn_parent = p;
882 } else log(LOG_ERR, "rn_delete: couldn't find us\n");
885 if (t->rn_flags & RNF_ACTIVE) {
899 x->rn_left->rn_parent = x;
900 x->rn_right->rn_parent = x;
904 if (t->rn_left == tt)
909 if (p->rn_right == t)
915 * Demote routes attached to us.
918 if (x->rn_bit >= 0) {
919 for (mp = &x->rn_mklist; (m = *mp);)
923 /* If there are any key,mask pairs in a sibling
924 duped-key chain, some subset will appear sorted
925 in the same order attached to our mklist */
926 for (m = t->rn_mklist; m && x; x = x->rn_dupedkey)
927 if (m == x->rn_mklist) {
928 struct radix_mask *mm = m->rm_mklist;
930 if (--(m->rm_refs) < 0)
936 "rn_delete: Orphaned Mask %p at %p\n",
937 (void *)m, (void *)x);
941 * We may be holding an active internal node in the tree.
952 t->rn_left->rn_parent = t;
953 t->rn_right->rn_parent = t;
961 tt->rn_flags &= ~RNF_ACTIVE;
962 tt[1].rn_flags &= ~RNF_ACTIVE;
967 * This is the same as rn_walktree() except for the parameters and the
971 rn_walktree_from(h, a, m, f, w)
972 struct radix_node_head *h;
978 struct radix_node *base, *next;
979 u_char *xa = (u_char *)a;
980 u_char *xm = (u_char *)m;
981 register struct radix_node *rn, *last = 0 /* shut up gcc */;
986 * rn_search_m is sort-of-open-coded here. We cannot use the
987 * function because we need to keep track of the last node seen.
989 /* printf("about to search\n"); */
990 for (rn = h->rnh_treetop; rn->rn_bit >= 0; ) {
992 /* printf("rn_bit %d, rn_bmask %x, xm[rn_offset] %x\n",
993 rn->rn_bit, rn->rn_bmask, xm[rn->rn_offset]); */
994 if (!(rn->rn_bmask & xm[rn->rn_offset])) {
997 if (rn->rn_bmask & xa[rn->rn_offset]) {
1003 /* printf("done searching\n"); */
1006 * Two cases: either we stepped off the end of our mask,
1007 * in which case last == rn, or we reached a leaf, in which
1008 * case we want to start from the last node we looked at.
1009 * Either way, last is the node we want to start from.
1014 /* printf("rn %p, lastb %d\n", rn, lastb);*/
1017 * This gets complicated because we may delete the node
1018 * while applying the function f to it, so we need to calculate
1019 * the successor node in advance.
1021 while (rn->rn_bit >= 0)
1025 /* printf("node %p (%d)\n", rn, rn->rn_bit); */
1027 /* If at right child go back up, otherwise, go right */
1028 while (rn->rn_parent->rn_right == rn
1029 && !(rn->rn_flags & RNF_ROOT)) {
1032 /* if went up beyond last, stop */
1033 if (rn->rn_bit <= lastb) {
1035 /* printf("up too far\n"); */
1037 * XXX we should jump to the 'Process leaves'
1038 * part, because the values of 'rn' and 'next'
1039 * we compute will not be used. Not a big deal
1040 * because this loop will terminate, but it is
1041 * inefficient and hard to understand!
1047 * At the top of the tree, no need to traverse the right
1048 * half, prevent the traversal of the entire tree in the
1049 * case of default route.
1051 if (rn->rn_parent->rn_flags & RNF_ROOT)
1054 /* Find the next *leaf* since next node might vanish, too */
1055 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;)
1058 /* Process leaves */
1059 while ((rn = base) != 0) {
1060 base = rn->rn_dupedkey;
1061 /* printf("leaf %p\n", rn); */
1062 if (!(rn->rn_flags & RNF_ROOT)
1063 && (error = (*f)(rn, w)))
1068 if (rn->rn_flags & RNF_ROOT) {
1069 /* printf("root, stopping"); */
1078 rn_walktree(h, f, w)
1079 struct radix_node_head *h;
1084 struct radix_node *base, *next;
1085 register struct radix_node *rn = h->rnh_treetop;
1087 * This gets complicated because we may delete the node
1088 * while applying the function f to it, so we need to calculate
1089 * the successor node in advance.
1092 /* First time through node, go left */
1093 while (rn->rn_bit >= 0)
1097 /* If at right child go back up, otherwise, go right */
1098 while (rn->rn_parent->rn_right == rn
1099 && (rn->rn_flags & RNF_ROOT) == 0)
1101 /* Find the next *leaf* since next node might vanish, too */
1102 for (rn = rn->rn_parent->rn_right; rn->rn_bit >= 0;)
1105 /* Process leaves */
1106 while ((rn = base)) {
1107 base = rn->rn_dupedkey;
1108 if (!(rn->rn_flags & RNF_ROOT)
1109 && (error = (*f)(rn, w)))
1113 if (rn->rn_flags & RNF_ROOT)
1120 * Allocate and initialize an empty tree. This has 3 nodes, which are
1121 * part of the radix_node_head (in the order <left,root,right>) and are
1122 * marked RNF_ROOT so they cannot be freed.
1123 * The leaves have all-zero and all-one keys, with significant
1124 * bits starting at 'off'.
1125 * Return 1 on success, 0 on error.
1128 rn_inithead(head, off)
1132 register struct radix_node_head *rnh;
1133 register struct radix_node *t, *tt, *ttt;
1136 R_Zalloc(rnh, struct radix_node_head *, sizeof (*rnh));
1140 RADIX_NODE_HEAD_LOCK_INIT(rnh);
1143 t = rn_newpair(rn_zeros, off, rnh->rnh_nodes);
1144 ttt = rnh->rnh_nodes + 2;
1147 tt = t->rn_left; /* ... which in turn is rnh->rnh_nodes */
1148 tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE;
1149 tt->rn_bit = -1 - off;
1151 ttt->rn_key = rn_ones;
1152 rnh->rnh_addaddr = rn_addroute;
1153 rnh->rnh_deladdr = rn_delete;
1154 rnh->rnh_matchaddr = rn_match;
1155 rnh->rnh_lookup = rn_lookup;
1156 rnh->rnh_walktree = rn_walktree;
1157 rnh->rnh_walktree_from = rn_walktree_from;
1158 rnh->rnh_treetop = t;
1169 for (dom = domains; dom; dom = dom->dom_next)
1170 if (dom->dom_maxrtkey > max_keylen)
1171 max_keylen = dom->dom_maxrtkey;
1173 if (max_keylen == 0) {
1175 "rn_init: radix functions require max_keylen be set\n");
1178 R_Malloc(rn_zeros, char *, 3 * max_keylen);
1179 if (rn_zeros == NULL)
1181 bzero(rn_zeros, 3 * max_keylen);
1182 rn_ones = cp = rn_zeros + max_keylen;
1183 addmask_key = cplim = rn_ones + max_keylen;
1186 if (rn_inithead((void **)(void *)&mask_rnhead, 0) == 0)