/*      $NetBSD: radix.h,v 1.7 2025/02/27 20:11:12 rillig 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 acknowledgment:
 *      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.h     8.2 (Berkeley) 10/31/94
 */

#ifndef __RADIX_H_
#define __RADIX_H_

#include <sys/cdefs.h>
struct walkarg;

/*
 * Radix search tree node layout.
 */

struct radix_node {
        struct  radix_mask *rn_mklist;  /* list of masks contained in subtree */
        struct  radix_node *rn_p;       /* parent */
        short   rn_b;                   /* bit offset; -1-index(netmask) */
        char    rn_bmask;               /* node: mask for bit test*/
        u_char  rn_flags;               /* enumerated next */
#define RNF_NORMAL      1               /* leaf contains normal route */
#define RNF_ROOT        2               /* leaf is root leaf for tree */
#define RNF_ACTIVE      4               /* This node is alive (for rtfree) */
        union {
                struct {                        /* leaf only data: */
                        caddr_t rn_Key; /* object of search */
                        caddr_t rn_Mask;        /* netmask, if present */
                        struct  radix_node *rn_Dupedkey;
                } rn_leaf;
                struct {                        /* node only data: */
                        int     rn_Off;         /* where to start compare */
                        struct  radix_node *rn_L;/* progeny */
                        struct  radix_node *rn_R;/* progeny */
                }rn_node;
        }               rn_u;
#ifdef RN_DEBUG
        int rn_info;
        struct radix_node *rn_twin;
        struct radix_node *rn_ybro;
#endif
};

#define rn_dupedkey rn_u.rn_leaf.rn_Dupedkey
#define rn_key rn_u.rn_leaf.rn_Key
#define rn_mask rn_u.rn_leaf.rn_Mask
#define rn_off rn_u.rn_node.rn_Off
#define rn_l rn_u.rn_node.rn_L
#define rn_r rn_u.rn_node.rn_R

/*
 * Annotations to tree concerning potential routes applying to subtrees.
 */

extern struct radix_mask {
        short   rm_b;                   /* bit offset; -1-index(netmask) */
        char    rm_unused;              /* cf. rn_bmask */
        u_char  rm_flags;               /* cf. rn_flags */
        struct  radix_mask *rm_mklist;  /* more masks to try */
        union   {
                caddr_t rmu_mask;               /* the mask */
                struct  radix_node *rmu_leaf;   /* for normal routes */
        }       rm_rmu;
        int     rm_refs;                /* # of references to this struct */
} *rn_mkfreelist;

#define rm_mask rm_rmu.rmu_mask
#define rm_leaf rm_rmu.rmu_leaf         /* extra field would make 32 bytes */

#define MKGet(m) {\
        if (rn_mkfreelist) {\
                m = rn_mkfreelist; \
                rn_mkfreelist = (m)->rm_mklist; \
        } else \
                m = (struct radix_mask *)rtmalloc(sizeof(*(m)), "MKGet"); }\

#define MKFree(m) { (m)->rm_mklist = rn_mkfreelist; rn_mkfreelist = (m);}

struct radix_node_head {
        struct  radix_node *rnh_treetop;
        int     rnh_addrsize;           /* permit, but not require fixed keys */
        int     rnh_pktsize;            /* permit, but not require fixed keys */
        struct  radix_node *(*rnh_addaddr)      /* add based on sockaddr */
                (void *v, void *mask,
                     struct radix_node_head *head, struct radix_node nodes[]);
        struct  radix_node *(*rnh_addpkt)       /* add based on packet hdr */
                (void *v, void *mask,
                     struct radix_node_head *head, struct radix_node nodes[]);
        struct  radix_node *(*rnh_deladdr)      /* remove based on sockaddr */
                (void *v, void *mask, struct radix_node_head *head);
        struct  radix_node *(*rnh_delpkt)       /* remove based on packet hdr */
                (void *v, void *mask, struct radix_node_head *head);
        struct  radix_node *(*rnh_matchaddr)    /* locate based on sockaddr */
                (void *v, struct radix_node_head *head);
        struct  radix_node *(*rnh_lookup)       /* locate based on sockaddr */
                (void *v, void *mask, struct radix_node_head *head);
        struct  radix_node *(*rnh_matchpkt)     /* locate based on packet hdr */
                (void *v, struct radix_node_head *head);
        int     (*rnh_walktree)                 /* traverse tree */
                        (struct radix_node_head *head,
                         int (*f)(struct radix_node *, struct walkarg *),
                         struct walkarg *w);
        struct  radix_node rnh_nodes[3];        /* empty tree for common case */
};


#define Bcmp(a, b, n) memcmp(((void *)(a)), ((void *)(b)), (n))
#define Bcopy(a, b, n) memmove(((void *)(b)), ((void *)(a)), (size_t)(n))
#define Bzero(p, n) memset((void *)(p), 0, (size_t)(n))
#define Free(p) free((void *)p);

void     rn_init(void);
int      rn_inithead(void **, int);
int      rn_refines(void *, void *);
int      rn_walktree(struct radix_node_head *,
                     int (*)(struct radix_node *, struct walkarg *),
                     struct walkarg *);

struct radix_node
         *rn_addmask(void *, int, int),
         *rn_addroute(void *, void *, struct radix_node_head *,
                        struct radix_node [2]),
         *rn_delete(void *, void *, struct radix_node_head *),
         *rn_insert(void *, struct radix_node_head *, int *,
                        struct radix_node [2]),
         *rn_match(void *, struct radix_node_head *),
         *rn_newpair(void *, int, struct radix_node[2]),
         *rn_search(void *, struct radix_node *),
         *rn_search_m(void *, struct radix_node *, void *);

struct radix_node *rn_lookup(void *, void *, struct radix_node_head *);

#endif /* __RADIX_H_ */