freebsd-dev/sys/net/radix.h
Garrett Wollman 1a11e63e1d A couple months ago, Kirk and I were doing a walkthrough of the radix-tree
search routine, and scratching our heads over why it was so obfuscated.
This delta fixes a number of confusing style bugs and renames several
structure members to have more meaningful names.  There remain a number
of odd control-flow structures.  These changes do not affect the generated
code.
2000-04-23 04:00:00 +00:00

171 lines
6.6 KiB
C

/*
* 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.h 8.2 (Berkeley) 10/31/94
* $FreeBSD$
*/
#ifndef _RADIX_H_
#define _RADIX_H_
#ifdef MALLOC_DECLARE
MALLOC_DECLARE(M_RTABLE);
#endif
/*
* Radix search tree node layout.
*/
struct radix_node {
struct radix_mask *rn_mklist; /* list of masks contained in subtree */
struct radix_node *rn_parent; /* parent */
short rn_bit; /* 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_offset rn_u.rn_node.rn_Off
#define rn_left rn_u.rn_node.rn_L
#define rn_right rn_u.rn_node.rn_R
/*
* Annotations to tree concerning potential routes applying to subtrees.
*/
struct radix_mask {
short rm_bit; /* 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 */
};
#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 \
R_Malloc(m, struct radix_mask *, sizeof (*(m))); }\
#define MKFree(m) { (m)->rm_mklist = rn_mkfreelist; rn_mkfreelist = (m);}
typedef int walktree_f_t __P((struct radix_node *, void *));
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 */
__P((void *v, void *mask,
struct radix_node_head *head, struct radix_node nodes[]));
struct radix_node *(*rnh_addpkt) /* add based on packet hdr */
__P((void *v, void *mask,
struct radix_node_head *head, struct radix_node nodes[]));
struct radix_node *(*rnh_deladdr) /* remove based on sockaddr */
__P((void *v, void *mask, struct radix_node_head *head));
struct radix_node *(*rnh_delpkt) /* remove based on packet hdr */
__P((void *v, void *mask, struct radix_node_head *head));
struct radix_node *(*rnh_matchaddr) /* locate based on sockaddr */
__P((void *v, struct radix_node_head *head));
struct radix_node *(*rnh_lookup) /* locate based on sockaddr */
__P((void *v, void *mask, struct radix_node_head *head));
struct radix_node *(*rnh_matchpkt) /* locate based on packet hdr */
__P((void *v, struct radix_node_head *head));
int (*rnh_walktree) /* traverse tree */
__P((struct radix_node_head *head, walktree_f_t *f, void *w));
int (*rnh_walktree_from) /* traverse tree below a */
__P((struct radix_node_head *head, void *a, void *m,
walktree_f_t *f, void *w));
void (*rnh_close) /* do something when the last ref drops */
__P((struct radix_node *rn, struct radix_node_head *head));
struct radix_node rnh_nodes[3]; /* empty tree for common case */
};
#ifndef _KERNEL
#define Bcmp(a, b, n) bcmp(((char *)(a)), ((char *)(b)), (n))
#define Bcopy(a, b, n) bcopy(((char *)(a)), ((char *)(b)), (unsigned)(n))
#define Bzero(p, n) bzero((char *)(p), (int)(n));
#define R_Malloc(p, t, n) (p = (t) malloc((unsigned int)(n)))
#define Free(p) free((char *)p);
#else
#define Bcmp(a, b, n) bcmp(((caddr_t)(a)), ((caddr_t)(b)), (unsigned)(n))
#define Bcopy(a, b, n) bcopy(((caddr_t)(a)), ((caddr_t)(b)), (unsigned)(n))
#define Bzero(p, n) bzero((caddr_t)(p), (unsigned)(n));
#define R_Malloc(p, t, n) (p = (t) malloc((unsigned long)(n), M_RTABLE, M_DONTWAIT))
#define Free(p) free((caddr_t)p, M_RTABLE);
#endif /* _KERNEL */
void rn_init __P((void));
int rn_inithead __P((void **, int));
int rn_refines __P((void *, void *));
struct radix_node
*rn_addmask __P((void *, int, int)),
*rn_addroute __P((void *, void *, struct radix_node_head *,
struct radix_node [2])),
*rn_delete __P((void *, void *, struct radix_node_head *)),
*rn_lookup __P((void *v_arg, void *m_arg,
struct radix_node_head *head)),
*rn_match __P((void *, struct radix_node_head *));
#endif /* _RADIX_H_ */