mirror of
git://projects.qi-hardware.com/wernermisc.git
synced 2024-12-22 15:13:54 +02:00
03c5e4ffe7
- jrb.h, jrb.c (jrb_find_or_insert): new function to look for a node and to insert a new one if not found - id.c (make_id): use jrb_find_or_insert to avoid looking up new nodes twice - TODO: report the improvement
127 lines
3.9 KiB
C
127 lines
3.9 KiB
C
/*
|
|
Libraries for fields, doubly-linked lists and red-black trees.
|
|
Copyright (C) 2001 James S. Plank
|
|
|
|
This library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
This library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with this library; if not, write to the Free Software
|
|
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
|
|
---------------------------------------------------------------------------
|
|
Please see http://www.cs.utk.edu/~plank/plank/classes/cs360/360/notes/Libfdr/
|
|
for instruction on how to use this library.
|
|
|
|
Jim Plank
|
|
plank@cs.utk.edu
|
|
http://www.cs.utk.edu/~plank
|
|
|
|
Associate Professor
|
|
Department of Computer Science
|
|
University of Tennessee
|
|
203 Claxton Complex
|
|
1122 Volunteer Blvd.
|
|
Knoxville, TN 37996-3450
|
|
|
|
865-974-4397
|
|
Fax: 865-974-4404
|
|
*/
|
|
|
|
/* Heavily edited and reformatted to K&R style 2010 by Werner Almesberger */
|
|
|
|
|
|
#ifndef _JRB_H_
|
|
#define _JRB_H_
|
|
|
|
/* Main jrb_node. You only ever use the fields
|
|
flink
|
|
blink
|
|
k.key or k.ikey
|
|
v.val
|
|
*/
|
|
|
|
|
|
struct jrb {
|
|
unsigned char red;
|
|
unsigned char internal;
|
|
unsigned char left;
|
|
unsigned char roothead; /* (bit 1 is root, bit 2 is head) */
|
|
struct jrb *flink;
|
|
struct jrb *blink;
|
|
struct jrb *parent;
|
|
void *key;
|
|
void *val;
|
|
};
|
|
|
|
|
|
struct jrb *make_jrb(void); /* Creates a new rb-tree */
|
|
|
|
|
|
/* Creates a node with key key and val val and inserts it into the tree.
|
|
jrb_insert uses strcmp() as comparison funcion. jrb_inserti uses <>=,
|
|
jrb_insertg uses func() */
|
|
|
|
struct jrb *jrb_insert(struct jrb *tree, void *key, void *val,
|
|
int (*func)(const void *a, const void *b));
|
|
|
|
/* If the key already exists, return the node (without altering it).
|
|
Otherwise, insert a new node. */
|
|
|
|
struct jrb *jrb_find_or_insert(struct jrb *tree, void *key, void *val,
|
|
int (*func)(const void *a, const void *b));
|
|
|
|
/* returns an external node in t whose value is equal k. Returns NULL if
|
|
there is no such node in the tree */
|
|
|
|
struct jrb *jrb_find(struct jrb *root, const void *key,
|
|
int (*func)(const void *a, const void *b));
|
|
|
|
/* returns an external node in t whose value is equal
|
|
k or whose value is the smallest value greater than k. Sets found to
|
|
1 if the key was found, and 0 otherwise. */
|
|
|
|
struct jrb *jrb_find_gte(struct jrb *root, const void *key,
|
|
int (*func)(const void *a, const void *b), int *found);
|
|
|
|
|
|
/* Creates a node with key key and val val and inserts it into the
|
|
tree before/after node nd. Does not check to ensure that you are
|
|
keeping the correct order */
|
|
|
|
void jrb_delete_node(struct jrb *node); /* Deletes and frees a node (but
|
|
not the key or val) */
|
|
void jrb_free_tree(struct jrb *root); /* Deletes and frees an entire tree */
|
|
|
|
void *jrb_val(struct jrb *node); /* Returns node->v.val -- this is to shut
|
|
lint up */
|
|
|
|
int jrb_nblack(struct jrb *n); /* returns # of black nodes in path from
|
|
n to the root */
|
|
int jrb_plength(struct jrb *n); /* returns the # of nodes in path from
|
|
n to the root */
|
|
|
|
#define jrb_first(n) ((n)->flink)
|
|
#define jrb_last(n) ((n)->blink)
|
|
#define jrb_next(n) ((n)->flink)
|
|
#define jrb_prev(n) ((n)->blink)
|
|
#define jrb_empty(t) ((t)->flink == (t))
|
|
#ifndef jrb_nil
|
|
#define jrb_nil(t) (t)
|
|
#endif
|
|
|
|
#define jrb_traverse(ptr, lst) \
|
|
for (ptr = jrb_first(lst); ptr != jrb_nil(lst); ptr = jrb_next(ptr))
|
|
|
|
#define jrb_rtraverse(ptr, lst) \
|
|
for (ptr = jrb_last(lst); ptr != jrb_nil(lst); ptr = jrb_prev(ptr))
|
|
|
|
#endif
|