/* $NetBSD: radix.c,v 1.3 1996/09/24 16:24:18 christos Exp $ */ /* * Copyright (c) 1988, 1989, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)radix.c 8.4 (Berkeley) 11/2/94 */ /* * Routines to build and maintain radix trees for routing lookups. */ #if !defined(lint) && !defined(sgi) && !defined(__NetBSD__) static char sccsid[] = "@(#)rdisc.c 8.1 (Berkeley) x/y/95"; #elif defined(__NetBSD__) static char rcsid[] = "$NetBSD: radix.c,v 1.3 1996/09/24 16:24:18 christos Exp $"; #endif #include "defs.h" #define log(x, msg) syslog(x, msg) #define panic(s) {log(LOG_ERR,s); exit(1);} #define min(a,b) (((a)<(b))?(a):(b)) int max_keylen; struct radix_mask *rn_mkfreelist; struct radix_node_head *mask_rnhead; static char *addmask_key; static char normal_chars[] = {0, 0x80, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc, 0xfe, -1}; static char *rn_zeros, *rn_ones; #define rn_masktop (mask_rnhead->rnh_treetop) #undef Bcmp #define Bcmp(a, b, l) (l == 0 ? 0 : bcmp((caddr_t)(a), (caddr_t)(b), (u_long)l)) static int rn_satsifies_leaf(char *, struct radix_node *, int); /* * The data structure for the keys is a radix tree with one way * branching removed. The index rn_b at an internal node n represents a bit * position to be tested. The tree is arranged so that all descendants * of a node n have keys whose bits all agree up to position rn_b - 1. * (We say the index of n is rn_b.) * * There is at least one descendant which has a one bit at position rn_b, * and at least one with a zero there. * * A route is determined by a pair of key and mask. We require that the * bit-wise logical and of the key and mask to be the key. * We define the index of a route to associated with the mask to be * the first bit number in the mask where 0 occurs (with bit number 0 * representing the highest order bit). * * We say a mask is normal if every bit is 0, past the index of the mask. * If a node n has a descendant (k, m) with index(m) == index(n) == rn_b, * and m is a normal mask, then the route applies to every descendant of n. * If the index(m) < rn_b, this implies the trailing last few bits of k * before bit b are all 0, (and hence consequently true of every descendant * of n), so the route applies to all descendants of the node as well. * * Similar logic shows that a non-normal mask m such that * index(m) <= index(n) could potentially apply to many children of n. * Thus, for each non-host route, we attach its mask to a list at an internal * node as high in the tree as we can go. * * The present version of the code makes use of normal routes in short- * circuiting an explict mask and compare operation when testing whether * a key satisfies a normal route, and also in remembering the unique leaf * that governs a subtree. */ struct radix_node * rn_search(void *v_arg, struct radix_node *head) { register struct radix_node *x; register caddr_t v; for (x = head, v = v_arg; x->rn_b >= 0;) { if (x->rn_bmask & v[x->rn_off]) x = x->rn_r; else x = x->rn_l; } return (x); } struct radix_node * rn_search_m(void *v_arg, struct radix_node *head, void *m_arg) { register struct radix_node *x; register caddr_t v = v_arg, m = m_arg; for (x = head; x->rn_b >= 0;) { if ((x->rn_bmask & m[x->rn_off]) && (x->rn_bmask & v[x->rn_off])) x = x->rn_r; else x = x->rn_l; } return x; } int rn_refines(void* m_arg, void *n_arg) { register caddr_t m = m_arg, n = n_arg; register caddr_t lim, lim2 = lim = n + *(u_char *)n; int longer = (*(u_char *)n++) - (int)(*(u_char *)m++); int masks_are_equal = 1; if (longer > 0) lim -= longer; while (n < lim) { if (*n & ~(*m)) return 0; if (*n++ != *m++) masks_are_equal = 0; } while (n < lim2) if (*n++) return 0; if (masks_are_equal && (longer < 0)) for (lim2 = m - longer; m < lim2; ) if (*m++) return 1; return (!masks_are_equal); } struct radix_node * rn_lookup(v_arg, m_arg, head) void *v_arg, *m_arg; struct radix_node_head *head; { register struct radix_node *x; caddr_t netmask = 0; if (m_arg) { if ((x = rn_addmask(m_arg, 1, head->rnh_treetop->rn_off)) == 0) return (0); netmask = x->rn_key; } x = rn_match(v_arg, head); if (x && netmask) { while (x && x->rn_mask != netmask) x = x->rn_dupedkey; } return x; } static int rn_satsifies_leaf(char *trial, register struct radix_node *leaf, int skip) { register char *cp = trial, *cp2 = leaf->rn_key, *cp3 = leaf->rn_mask; char *cplim; int length = min(*(u_char *)cp, *(u_char *)cp2); if (cp3 == 0) cp3 = rn_ones; else length = min(length, *(u_char *)cp3); cplim = cp + length; cp3 += skip; cp2 += skip; for (cp += skip; cp < cplim; cp++, cp2++, cp3++) if ((*cp ^ *cp2) & *cp3) return 0; return 1; } struct radix_node * rn_match(void *v_arg, struct radix_node_head *head) { caddr_t v = v_arg; register struct radix_node *t = head->rnh_treetop, *x; register caddr_t cp = v, cp2; caddr_t cplim; struct radix_node *saved_t, *top = t; int off = t->rn_off, vlen = *(u_char *)cp, matched_off; register int test, b, rn_b; /* * Open code rn_search(v, top) to avoid overhead of extra * subroutine call. */ for (; t->rn_b >= 0; ) { if (t->rn_bmask & cp[t->rn_off]) t = t->rn_r; else t = t->rn_l; } /* * See if we match exactly as a host destination * or at least learn how many bits match, for normal mask finesse. * * It doesn't hurt us to limit how many bytes to check * to the length of the mask, since if it matches we had a genuine * match and the leaf we have is the most specific one anyway; * if it didn't match with a shorter length it would fail * with a long one. This wins big for class B&C netmasks which * are probably the most common case... */ if (t->rn_mask) vlen = *(u_char *)t->rn_mask; cp += off; cp2 = t->rn_key + off; cplim = v + vlen; for (; cp < cplim; cp++, cp2++) if (*cp != *cp2) goto on1; /* * This extra grot is in case we are explicitly asked * to look up the default. Ugh! * Or 255.255.255.255 * * In this case, we have a complete match of the key. Unless * the node is one of the roots, we are finished. * If it is the zeros root, then take what we have, prefering * any real data. * If it is the ones root, then pretend the target key was followed * by a byte of zeros. */ if (!(t->rn_flags & RNF_ROOT)) return t; /* not a root */ if (t->rn_dupedkey) { t = t->rn_dupedkey; return t; /* have some real data */ } if (*(cp-1) == 0) return t; /* not the ones root */ b = 0; /* fake a zero after 255.255.255.255 */ goto on2; on1: test = (*cp ^ *cp2) & 0xff; /* find first bit that differs */ for (b = 7; (test >>= 1) > 0;) b--; on2: matched_off = cp - v; b += matched_off << 3; rn_b = -1 - b; /* * If there is a host route in a duped-key chain, it will be first. */ if ((saved_t = t)->rn_mask == 0) t = t->rn_dupedkey; for (; t; t = t->rn_dupedkey) /* * Even if we don't match exactly as a host, * we may match if the leaf we wound up at is * a route to a net. */ if (t->rn_flags & RNF_NORMAL) { if (rn_b <= t->rn_b) return t; } else if (rn_satsifies_leaf(v, t, matched_off)) return t; t = saved_t; /* start searching up the tree */ do { register struct radix_mask *m; t = t->rn_p; if ((m = t->rn_mklist)) { /* * If non-contiguous masks ever become important * we can restore the masking and open coding of * the search and satisfaction test and put the * calculation of "off" back before the "do". */ do { if (m->rm_flags & RNF_NORMAL) { if (rn_b <= m->rm_b) return (m->rm_leaf); } else { off = min(t->rn_off, matched_off); x = rn_search_m(v, t, m->rm_mask); while (x && x->rn_mask != m->rm_mask) x = x->rn_dupedkey; if (x && rn_satsifies_leaf(v, x, off)) return x; } } while ((m = m->rm_mklist)); } } while (t != top); return 0; } #ifdef RN_DEBUG int rn_nodenum; struct radix_node *rn_clist; int rn_saveinfo; int rn_debug = 1; #endif struct radix_node * rn_newpair(void *v, int b, struct radix_node nodes[2]) { register struct radix_node *tt = nodes, *t = tt + 1; t->rn_b = b; t->rn_bmask = 0x80 >> (b & 7); t->rn_l = tt; t->rn_off = b >> 3; tt->rn_b = -1; tt->rn_key = (caddr_t)v; tt->rn_p = t; tt->rn_flags = t->rn_flags = RNF_ACTIVE; #ifdef RN_DEBUG tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; #endif return t; } struct radix_node * rn_insert(void* v_arg, struct radix_node_head *head, int *dupentry, struct radix_node nodes[2]) { caddr_t v = v_arg; struct radix_node *top = head->rnh_treetop; int head_off = top->rn_off, vlen = (int)*((u_char *)v); register struct radix_node *t = rn_search(v_arg, top); register caddr_t cp = v + head_off; register int b; struct radix_node *tt; /* * Find first bit at which v and t->rn_key differ */ { register caddr_t cp2 = t->rn_key + head_off; register int cmp_res; caddr_t cplim = v + vlen; while (cp < cplim) if (*cp2++ != *cp++) goto on1; /* handle adding 255.255.255.255 */ if (!(t->rn_flags & RNF_ROOT) || *(cp2-1) == 0) { *dupentry = 1; return t; } on1: *dupentry = 0; cmp_res = (cp[-1] ^ cp2[-1]) & 0xff; for (b = (cp - v) << 3; cmp_res; b--) cmp_res >>= 1; } { register struct radix_node *p, *x = top; cp = v; do { p = x; if (cp[x->rn_off] & x->rn_bmask) x = x->rn_r; else x = x->rn_l; } while (b > (unsigned) x->rn_b); /* x->rn_b < b && x->rn_b >= 0 */ #ifdef RN_DEBUG if (rn_debug) log(LOG_DEBUG, "rn_insert: Going In:\n"), traverse(p); #endif t = rn_newpair(v_arg, b, nodes); tt = t->rn_l; if ((cp[p->rn_off] & p->rn_bmask) == 0) p->rn_l = t; else p->rn_r = t; x->rn_p = t; t->rn_p = p; /* frees x, p as temp vars below */ if ((cp[t->rn_off] & t->rn_bmask) == 0) { t->rn_r = x; } else { t->rn_r = tt; t->rn_l = x; } #ifdef RN_DEBUG if (rn_debug) log(LOG_DEBUG, "rn_insert: Coming Out:\n"), traverse(p); #endif } return (tt); } struct radix_node * rn_addmask(void *n_arg, int search, int skip) { caddr_t netmask = (caddr_t)n_arg; register struct radix_node *x; register caddr_t cp, cplim; register int b = 0, mlen, j; int maskduplicated, m0, isnormal; struct radix_node *saved_x; static int last_zeroed = 0; if ((mlen = *(u_char *)netmask) > max_keylen) mlen = max_keylen; if (skip == 0) skip = 1; if (mlen <= skip) return (mask_rnhead->rnh_nodes); if (skip > 1) Bcopy(rn_ones + 1, addmask_key + 1, skip - 1); if ((m0 = mlen) > skip) Bcopy(netmask + skip, addmask_key + skip, mlen - skip); /* * Trim trailing zeroes. */ for (cp = addmask_key + mlen; (cp > addmask_key) && cp[-1] == 0;) cp--; mlen = cp - addmask_key; if (mlen <= skip) { if (m0 >= last_zeroed) last_zeroed = mlen; return (mask_rnhead->rnh_nodes); } if (m0 < last_zeroed) Bzero(addmask_key + m0, last_zeroed - m0); *addmask_key = last_zeroed = mlen; x = rn_search(addmask_key, rn_masktop); if (Bcmp(addmask_key, x->rn_key, mlen) != 0) x = 0; if (x || search) return (x); R_Malloc(x, struct radix_node *, max_keylen + 2 * sizeof (*x)); if ((saved_x = x) == 0) return (0); Bzero(x, max_keylen + 2 * sizeof (*x)); netmask = cp = (caddr_t)(x + 2); Bcopy(addmask_key, cp, mlen); x = rn_insert(cp, mask_rnhead, &maskduplicated, x); if (maskduplicated) { log(LOG_ERR, "rn_addmask: mask impossibly already in tree"); Free(saved_x); return (x); } /* * Calculate index of mask, and check for normalcy. */ cplim = netmask + mlen; isnormal = 1; for (cp = netmask + skip; (cp < cplim) && *(u_char *)cp == 0xff;) cp++; if (cp != cplim) { for (j = 0x80; (j & *cp) != 0; j >>= 1) b++; if (*cp != normal_chars[b] || cp != (cplim - 1)) isnormal = 0; } b += (cp - netmask) << 3; x->rn_b = -1 - b; if (isnormal) x->rn_flags |= RNF_NORMAL; return (x); } static int /* XXX: arbitrary ordering for non-contiguous masks */ rn_lexobetter(void *m_arg, void *n_arg) { register u_char *mp = m_arg, *np = n_arg, *lim; if (*mp > *np) return 1; /* not really, but need to check longer one first */ if (*mp == *np) for (lim = mp + *mp; mp < lim;) if (*mp++ > *np++) return 1; return 0; } static struct radix_mask * rn_new_radix_mask(register struct radix_node *tt, register struct radix_mask *next) { register struct radix_mask *m; MKGet(m); if (m == 0) { log(LOG_ERR, "Mask for route not entered\n"); return (0); } Bzero(m, sizeof *m); m->rm_b = tt->rn_b; m->rm_flags = tt->rn_flags; if (tt->rn_flags & RNF_NORMAL) m->rm_leaf = tt; else m->rm_mask = tt->rn_mask; m->rm_mklist = next; tt->rn_mklist = m; return m; } struct radix_node * rn_addroute(void *v_arg, void *n_arg, struct radix_node_head *head, struct radix_node treenodes[2]) { caddr_t v = (caddr_t)v_arg, netmask = (caddr_t)n_arg; register struct radix_node *t, *x = 0, *tt; struct radix_node *saved_tt, *top = head->rnh_treetop; short b = 0, b_leaf = 0; int keyduplicated; caddr_t mmask; struct radix_mask *m, **mp; /* * In dealing with non-contiguous masks, there may be * many different routes which have the same mask. * We will find it useful to have a unique pointer to * the mask to speed avoiding duplicate references at * nodes and possibly save time in calculating indices. */ if (netmask) { if ((x = rn_addmask(netmask, 0, top->rn_off)) == 0) return (0); b_leaf = x->rn_b; b = -1 - x->rn_b; netmask = x->rn_key; } /* * Deal with duplicated keys: attach node to previous instance */ saved_tt = tt = rn_insert(v, head, &keyduplicated, treenodes); if (keyduplicated) { for (t = tt; tt; t = tt, tt = tt->rn_dupedkey) { if (tt->rn_mask == netmask) return (0); if (netmask == 0 || (tt->rn_mask && ((b_leaf < tt->rn_b) || /* index(netmask) > node */ rn_refines(netmask, tt->rn_mask) || rn_lexobetter(netmask, tt->rn_mask)))) break; } /* * If the mask is not duplicated, we wouldn't * find it among possible duplicate key entries * anyway, so the above test doesn't hurt. * * We sort the masks for a duplicated key the same way as * in a masklist -- most specific to least specific. * This may require the unfortunate nuisance of relocating * the head of the list. */ if (tt == saved_tt) { struct radix_node *xx = x; /* link in at head of list */ (tt = treenodes)->rn_dupedkey = t; tt->rn_flags = t->rn_flags; tt->rn_p = x = t->rn_p; if (x->rn_l == t) x->rn_l = tt; else x->rn_r = tt; saved_tt = tt; x = xx; } else { (tt = treenodes)->rn_dupedkey = t->rn_dupedkey; t->rn_dupedkey = tt; } #ifdef RN_DEBUG t=tt+1; tt->rn_info = rn_nodenum++; t->rn_info = rn_nodenum++; tt->rn_twin = t; tt->rn_ybro = rn_clist; rn_clist = tt; #endif tt->rn_key = (caddr_t) v; tt->rn_b = -1; tt->rn_flags = RNF_ACTIVE; } /* * Put mask in tree. */ if (netmask) { tt->rn_mask = netmask; tt->rn_b = x->rn_b; tt->rn_flags |= x->rn_flags & RNF_NORMAL; } t = saved_tt->rn_p; if (keyduplicated) goto on2; b_leaf = -1 - t->rn_b; if (t->rn_r == saved_tt) x = t->rn_l; else x = t->rn_r; /* Promote general routes from below */ if (x->rn_b < 0) { for (mp = &t->rn_mklist; x; x = x->rn_dupedkey) if (x->rn_mask && (x->rn_b >= b_leaf) && x->rn_mklist == 0) { if ((*mp = m = rn_new_radix_mask(x, 0))) mp = &m->rm_mklist; } } else if (x->rn_mklist) { /* * Skip over masks whose index is > that of new node */ for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) if (m->rm_b >= b_leaf) break; t->rn_mklist = m; *mp = 0; } on2: /* Add new route to highest possible ancestor's list */ if ((netmask == 0) || (b > t->rn_b )) return tt; /* can't lift at all */ b_leaf = tt->rn_b; do { x = t; t = t->rn_p; } while (b <= t->rn_b && x != top); /* * Search through routes associated with node to * insert new route according to index. * Need same criteria as when sorting dupedkeys to avoid * double loop on deletion. */ for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) { if (m->rm_b < b_leaf) continue; if (m->rm_b > b_leaf) break; if (m->rm_flags & RNF_NORMAL) { mmask = m->rm_leaf->rn_mask; if (tt->rn_flags & RNF_NORMAL) { log(LOG_ERR, "Non-unique normal route, mask not entered"); return tt; } } else mmask = m->rm_mask; if (mmask == netmask) { m->rm_refs++; tt->rn_mklist = m; return tt; } if (rn_refines(netmask, mmask) || rn_lexobetter(netmask, mmask)) break; } *mp = rn_new_radix_mask(tt, *mp); return tt; } struct radix_node * rn_delete(void *v_arg, void *netmask_arg, struct radix_node_head *head) { register struct radix_node *t, *p, *x, *tt; struct radix_mask *m, *saved_m, **mp; struct radix_node *dupedkey, *saved_tt, *top; caddr_t v, netmask; int b, head_off, vlen; v = v_arg; netmask = netmask_arg; x = head->rnh_treetop; tt = rn_search(v, x); head_off = x->rn_off; vlen = *(u_char *)v; saved_tt = tt; top = x; if (tt == 0 || Bcmp(v + head_off, tt->rn_key + head_off, vlen - head_off)) return (0); /* * Delete our route from mask lists. */ if (netmask) { if ((x = rn_addmask(netmask, 1, head_off)) == 0) return (0); netmask = x->rn_key; while (tt->rn_mask != netmask) if ((tt = tt->rn_dupedkey) == 0) return (0); } if (tt->rn_mask == 0 || (saved_m = m = tt->rn_mklist) == 0) goto on1; if (tt->rn_flags & RNF_NORMAL) { if (m->rm_leaf != tt || m->rm_refs > 0) { log(LOG_ERR, "rn_delete: inconsistent annotation\n"); return 0; /* dangling ref could cause disaster */ } } else { if (m->rm_mask != tt->rn_mask) { log(LOG_ERR, "rn_delete: inconsistent annotation\n"); goto on1; } if (--m->rm_refs >= 0) goto on1; } b = -1 - tt->rn_b; t = saved_tt->rn_p; if (b > t->rn_b) goto on1; /* Wasn't lifted at all */ do { x = t; t = t->rn_p; } while (b <= t->rn_b && x != top); for (mp = &x->rn_mklist; (m = *mp); mp = &m->rm_mklist) if (m == saved_m) { *mp = m->rm_mklist; MKFree(m); break; } if (m == 0) { log(LOG_ERR, "rn_delete: couldn't find our annotation\n"); if (tt->rn_flags & RNF_NORMAL) return (0); /* Dangling ref to us */ } on1: /* * Eliminate us from tree */ if (tt->rn_flags & RNF_ROOT) return (0); #ifdef RN_DEBUG /* Get us out of the creation list */ for (t = rn_clist; t && t->rn_ybro != tt; t = t->rn_ybro) {} if (t) t->rn_ybro = tt->rn_ybro; #endif t = tt->rn_p; if ((dupedkey = saved_tt->rn_dupedkey)) { if (tt == saved_tt) { x = dupedkey; x->rn_p = t; if (t->rn_l == tt) t->rn_l = x; else t->rn_r = x; } else { for (x = p = saved_tt; p && p->rn_dupedkey != tt;) p = p->rn_dupedkey; if (p) p->rn_dupedkey = tt->rn_dupedkey; else log(LOG_ERR, "rn_delete: couldn't find us\n"); } t = tt + 1; if (t->rn_flags & RNF_ACTIVE) { #ifndef RN_DEBUG *++x = *t; p = t->rn_p; #else b = t->rn_info; *++x = *t; t->rn_info = b; p = t->rn_p; #endif if (p->rn_l == t) p->rn_l = x; else p->rn_r = x; x->rn_l->rn_p = x; x->rn_r->rn_p = x; } goto out; } if (t->rn_l == tt) x = t->rn_r; else x = t->rn_l; p = t->rn_p; if (p->rn_r == t) p->rn_r = x; else p->rn_l = x; x->rn_p = p; /* * Demote routes attached to us. */ if (t->rn_mklist) { if (x->rn_b >= 0) { for (mp = &x->rn_mklist; (m = *mp);) mp = &m->rm_mklist; *mp = t->rn_mklist; } else { /* If there are any key,mask pairs in a sibling duped-key chain, some subset will appear sorted in the same order attached to our mklist */ for (m = t->rn_mklist; m && x; x = x->rn_dupedkey) if (m == x->rn_mklist) { struct radix_mask *mm = m->rm_mklist; x->rn_mklist = 0; if (--(m->rm_refs) < 0) MKFree(m); m = mm; } if (m) syslog(LOG_ERR, "%s %lx at %lx\n", "rn_delete: Orphaned Mask", (unsigned long)m, (unsigned long)x); } } /* * We may be holding an active internal node in the tree. */ x = tt + 1; if (t != x) { #ifndef RN_DEBUG *t = *x; #else b = t->rn_info; *t = *x; t->rn_info = b; #endif t->rn_l->rn_p = t; t->rn_r->rn_p = t; p = x->rn_p; if (p->rn_l == x) p->rn_l = t; else p->rn_r = t; } out: tt->rn_flags &= ~RNF_ACTIVE; tt[1].rn_flags &= ~RNF_ACTIVE; return (tt); } int rn_walktree(struct radix_node_head *h, register int (*f)(struct radix_node *, struct walkarg *), struct walkarg *w) { int error; struct radix_node *base, *next; register struct radix_node *rn = h->rnh_treetop; /* * This gets complicated because we may delete the node * while applying the function f to it, so we need to calculate * the successor node in advance. */ /* First time through node, go left */ while (rn->rn_b >= 0) rn = rn->rn_l; for (;;) { base = rn; /* If at right child go back up, otherwise, go right */ while (rn->rn_p->rn_r == rn && (rn->rn_flags & RNF_ROOT) == 0) rn = rn->rn_p; /* Find the next *leaf* since next node might vanish, too */ for (rn = rn->rn_p->rn_r; rn->rn_b >= 0;) rn = rn->rn_l; next = rn; /* Process leaves */ while ((rn = base)) { base = rn->rn_dupedkey; if (!(rn->rn_flags & RNF_ROOT) && (error = (*f)(rn, w))) return (error); } rn = next; if (rn->rn_flags & RNF_ROOT) return (0); } /* NOTREACHED */ } int rn_inithead(void **head, int off) { register struct radix_node_head *rnh; register struct radix_node *t, *tt, *ttt; if (*head) return (1); R_Malloc(rnh, struct radix_node_head *, sizeof (*rnh)); if (rnh == 0) return (0); Bzero(rnh, sizeof (*rnh)); *head = rnh; t = rn_newpair(rn_zeros, off, rnh->rnh_nodes); ttt = rnh->rnh_nodes + 2; t->rn_r = ttt; t->rn_p = t; tt = t->rn_l; tt->rn_flags = t->rn_flags = RNF_ROOT | RNF_ACTIVE; tt->rn_b = -1 - off; *ttt = *tt; ttt->rn_key = rn_ones; rnh->rnh_addaddr = rn_addroute; rnh->rnh_deladdr = rn_delete; rnh->rnh_matchaddr = rn_match; rnh->rnh_lookup = rn_lookup; rnh->rnh_walktree = rn_walktree; rnh->rnh_treetop = t; return (1); } void rn_init(void) { char *cp, *cplim; if (max_keylen == 0) { printf("rn_init: radix functions require max_keylen be set\n"); return; } R_Malloc(rn_zeros, char *, 3 * max_keylen); if (rn_zeros == NULL) panic("rn_init"); Bzero(rn_zeros, 3 * max_keylen); rn_ones = cp = rn_zeros + max_keylen; addmask_key = cplim = rn_ones + max_keylen; while (cp < cplim) *cp++ = -1; if (rn_inithead((void **)&mask_rnhead, 0) == 0) panic("rn_init 2"); }