diff options
Diffstat (limited to 'lib/openbsd-tree.c')
| -rw-r--r-- | lib/openbsd-tree.c | 620 |
1 files changed, 620 insertions, 0 deletions
diff --git a/lib/openbsd-tree.c b/lib/openbsd-tree.c new file mode 100644 index 0000000..98d2e15 --- /dev/null +++ b/lib/openbsd-tree.c @@ -0,0 +1,620 @@ +/* $OpenBSD: subr_tree.c,v 1.9 2017/06/08 03:30:52 dlg Exp $ */ + +/* + * Copyright 2002 Niels Provos <provos@citi.umich.edu> + * 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. + */ + +/* + * Copyright (c) 2016 David Gwynne <dlg@openbsd.org> + * + * Permission to use, copy, modify, and distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <stdlib.h> + +#include <lib/openbsd-tree.h> + +static inline struct rb_entry *rb_n2e(const struct rb_type *t, void *node) +{ + unsigned long addr = (unsigned long)node; + + return ((struct rb_entry *)(addr + t->t_offset)); +} + +static inline void *rb_e2n(const struct rb_type *t, struct rb_entry *rbe) +{ + unsigned long addr = (unsigned long)rbe; + + return ((void *)(addr - t->t_offset)); +} + +#define RBE_LEFT(_rbe) (_rbe)->rbt_left +#define RBE_RIGHT(_rbe) (_rbe)->rbt_right +#define RBE_PARENT(_rbe) (_rbe)->rbt_parent +#define RBE_COLOR(_rbe) (_rbe)->rbt_color + +#define RBH_ROOT(_rbt) (_rbt)->rbt_root + +static inline void rbe_set(struct rb_entry *rbe, struct rb_entry *parent) +{ + RBE_PARENT(rbe) = parent; + RBE_LEFT(rbe) = RBE_RIGHT(rbe) = NULL; + RBE_COLOR(rbe) = RB_RED; +} + +static inline void rbe_set_blackred(struct rb_entry *black, + struct rb_entry *red) +{ + RBE_COLOR(black) = RB_BLACK; + RBE_COLOR(red) = RB_RED; +} + +static inline void rbe_augment(const struct rb_type *t, struct rb_entry *rbe) +{ + (*t->t_augment)(rb_e2n(t, rbe)); +} + +static inline void rbe_if_augment(const struct rb_type *t, struct rb_entry *rbe) +{ + if (t->t_augment != NULL) + rbe_augment(t, rbe); +} + +static inline void rbe_rotate_left(const struct rb_type *t, + struct rbt_tree *rbt, struct rb_entry *rbe) +{ + struct rb_entry *parent; + struct rb_entry *tmp; + + tmp = RBE_RIGHT(rbe); + RBE_RIGHT(rbe) = RBE_LEFT(tmp); + if (RBE_RIGHT(rbe) != NULL) + RBE_PARENT(RBE_LEFT(tmp)) = rbe; + + parent = RBE_PARENT(rbe); + RBE_PARENT(tmp) = parent; + if (parent != NULL) { + if (rbe == RBE_LEFT(parent)) + RBE_LEFT(parent) = tmp; + else + RBE_RIGHT(parent) = tmp; + } else + RBH_ROOT(rbt) = tmp; + + RBE_LEFT(tmp) = rbe; + RBE_PARENT(rbe) = tmp; + + if (t->t_augment != NULL) { + rbe_augment(t, rbe); + rbe_augment(t, tmp); + parent = RBE_PARENT(tmp); + if (parent != NULL) + rbe_augment(t, parent); + } +} + +static inline void rbe_rotate_right(const struct rb_type *t, + struct rbt_tree *rbt, struct rb_entry *rbe) +{ + struct rb_entry *parent; + struct rb_entry *tmp; + + tmp = RBE_LEFT(rbe); + RBE_LEFT(rbe) = RBE_RIGHT(tmp); + if (RBE_LEFT(rbe) != NULL) + RBE_PARENT(RBE_RIGHT(tmp)) = rbe; + + parent = RBE_PARENT(rbe); + RBE_PARENT(tmp) = parent; + if (parent != NULL) { + if (rbe == RBE_LEFT(parent)) + RBE_LEFT(parent) = tmp; + else + RBE_RIGHT(parent) = tmp; + } else + RBH_ROOT(rbt) = tmp; + + RBE_RIGHT(tmp) = rbe; + RBE_PARENT(rbe) = tmp; + + if (t->t_augment != NULL) { + rbe_augment(t, rbe); + rbe_augment(t, tmp); + parent = RBE_PARENT(tmp); + if (parent != NULL) + rbe_augment(t, parent); + } +} + +static inline void rbe_insert_color(const struct rb_type *t, + struct rbt_tree *rbt, struct rb_entry *rbe) +{ + struct rb_entry *parent, *gparent, *tmp; + + while ((parent = RBE_PARENT(rbe)) != NULL + && RBE_COLOR(parent) == RB_RED) { + gparent = RBE_PARENT(parent); + + if (parent == RBE_LEFT(gparent)) { + tmp = RBE_RIGHT(gparent); + if (tmp != NULL && RBE_COLOR(tmp) == RB_RED) { + RBE_COLOR(tmp) = RB_BLACK; + rbe_set_blackred(parent, gparent); + rbe = gparent; + continue; + } + + if (RBE_RIGHT(parent) == rbe) { + rbe_rotate_left(t, rbt, parent); + tmp = parent; + parent = rbe; + rbe = tmp; + } + + rbe_set_blackred(parent, gparent); + rbe_rotate_right(t, rbt, gparent); + } else { + tmp = RBE_LEFT(gparent); + if (tmp != NULL && RBE_COLOR(tmp) == RB_RED) { + RBE_COLOR(tmp) = RB_BLACK; + rbe_set_blackred(parent, gparent); + rbe = gparent; + continue; + } + + if (RBE_LEFT(parent) == rbe) { + rbe_rotate_right(t, rbt, parent); + tmp = parent; + parent = rbe; + rbe = tmp; + } + + rbe_set_blackred(parent, gparent); + rbe_rotate_left(t, rbt, gparent); + } + } + + RBE_COLOR(RBH_ROOT(rbt)) = RB_BLACK; +} + +static inline void rbe_remove_color(const struct rb_type *t, + struct rbt_tree *rbt, + struct rb_entry *parent, + struct rb_entry *rbe) +{ + struct rb_entry *tmp; + + while ((rbe == NULL || RBE_COLOR(rbe) == RB_BLACK) + && rbe != RBH_ROOT(rbt) && parent) { + if (RBE_LEFT(parent) == rbe) { + tmp = RBE_RIGHT(parent); + if (RBE_COLOR(tmp) == RB_RED) { + rbe_set_blackred(tmp, parent); + rbe_rotate_left(t, rbt, parent); + tmp = RBE_RIGHT(parent); + } + if ((RBE_LEFT(tmp) == NULL + || RBE_COLOR(RBE_LEFT(tmp)) == RB_BLACK) + && (RBE_RIGHT(tmp) == NULL + || RBE_COLOR(RBE_RIGHT(tmp)) == RB_BLACK)) { + RBE_COLOR(tmp) = RB_RED; + rbe = parent; + parent = RBE_PARENT(rbe); + } else { + if (RBE_RIGHT(tmp) == NULL + || RBE_COLOR(RBE_RIGHT(tmp)) == RB_BLACK) { + struct rb_entry *oleft; + + oleft = RBE_LEFT(tmp); + if (oleft != NULL) + RBE_COLOR(oleft) = RB_BLACK; + + RBE_COLOR(tmp) = RB_RED; + rbe_rotate_right(t, rbt, tmp); + tmp = RBE_RIGHT(parent); + } + + RBE_COLOR(tmp) = RBE_COLOR(parent); + RBE_COLOR(parent) = RB_BLACK; + if (RBE_RIGHT(tmp)) + RBE_COLOR(RBE_RIGHT(tmp)) = RB_BLACK; + + rbe_rotate_left(t, rbt, parent); + rbe = RBH_ROOT(rbt); + break; + } + } else { + tmp = RBE_LEFT(parent); + if (RBE_COLOR(tmp) == RB_RED) { + rbe_set_blackred(tmp, parent); + rbe_rotate_right(t, rbt, parent); + tmp = RBE_LEFT(parent); + } + + if ((RBE_LEFT(tmp) == NULL + || RBE_COLOR(RBE_LEFT(tmp)) == RB_BLACK) + && (RBE_RIGHT(tmp) == NULL + || RBE_COLOR(RBE_RIGHT(tmp)) == RB_BLACK)) { + RBE_COLOR(tmp) = RB_RED; + rbe = parent; + parent = RBE_PARENT(rbe); + } else { + if (RBE_LEFT(tmp) == NULL + || RBE_COLOR(RBE_LEFT(tmp)) == RB_BLACK) { + struct rb_entry *oright; + + oright = RBE_RIGHT(tmp); + if (oright != NULL) + RBE_COLOR(oright) = RB_BLACK; + + RBE_COLOR(tmp) = RB_RED; + rbe_rotate_left(t, rbt, tmp); + tmp = RBE_LEFT(parent); + } + + RBE_COLOR(tmp) = RBE_COLOR(parent); + RBE_COLOR(parent) = RB_BLACK; + if (RBE_LEFT(tmp) != NULL) + RBE_COLOR(RBE_LEFT(tmp)) = RB_BLACK; + + rbe_rotate_right(t, rbt, parent); + rbe = RBH_ROOT(rbt); + break; + } + } + } + + if (rbe != NULL) + RBE_COLOR(rbe) = RB_BLACK; +} + +static inline struct rb_entry * +rbe_remove(const struct rb_type *t, struct rbt_tree *rbt, struct rb_entry *rbe) +{ + struct rb_entry *child, *parent, *old = rbe; + unsigned int color; + + if (RBE_LEFT(rbe) == NULL) + child = RBE_RIGHT(rbe); + else if (RBE_RIGHT(rbe) == NULL) + child = RBE_LEFT(rbe); + else { + struct rb_entry *tmp; + + rbe = RBE_RIGHT(rbe); + while ((tmp = RBE_LEFT(rbe)) != NULL) + rbe = tmp; + + child = RBE_RIGHT(rbe); + parent = RBE_PARENT(rbe); + color = RBE_COLOR(rbe); + if (child != NULL) + RBE_PARENT(child) = parent; + if (parent != NULL) { + if (RBE_LEFT(parent) == rbe) + RBE_LEFT(parent) = child; + else + RBE_RIGHT(parent) = child; + + rbe_if_augment(t, parent); + } else + RBH_ROOT(rbt) = child; + if (RBE_PARENT(rbe) == old) + parent = rbe; + *rbe = *old; + + tmp = RBE_PARENT(old); + if (tmp != NULL) { + if (RBE_LEFT(tmp) == old) + RBE_LEFT(tmp) = rbe; + else + RBE_RIGHT(tmp) = rbe; + + rbe_if_augment(t, tmp); + } else + RBH_ROOT(rbt) = rbe; + + RBE_PARENT(RBE_LEFT(old)) = rbe; + if (RBE_RIGHT(old)) + RBE_PARENT(RBE_RIGHT(old)) = rbe; + + if (t->t_augment != NULL && parent != NULL) { + tmp = parent; + do { + rbe_augment(t, tmp); + tmp = RBE_PARENT(tmp); + } while (tmp != NULL); + } + + goto color; + } + + parent = RBE_PARENT(rbe); + color = RBE_COLOR(rbe); + + if (child != NULL) + RBE_PARENT(child) = parent; + if (parent != NULL) { + if (RBE_LEFT(parent) == rbe) + RBE_LEFT(parent) = child; + else + RBE_RIGHT(parent) = child; + + rbe_if_augment(t, parent); + } else + RBH_ROOT(rbt) = child; +color: + if (color == RB_BLACK) + rbe_remove_color(t, rbt, parent, child); + + return (old); +} + +void *_rb_remove(const struct rb_type *t, struct rbt_tree *rbt, void *elm) +{ + struct rb_entry *rbe = rb_n2e(t, elm); + struct rb_entry *old; + + old = rbe_remove(t, rbt, rbe); + + return (old == NULL ? NULL : rb_e2n(t, old)); +} + +void *_rb_insert(const struct rb_type *t, struct rbt_tree *rbt, void *elm) +{ + struct rb_entry *rbe = rb_n2e(t, elm); + struct rb_entry *tmp; + struct rb_entry *parent = NULL; + void *node; + int comp = 0; + + tmp = RBH_ROOT(rbt); + while (tmp != NULL) { + parent = tmp; + + node = rb_e2n(t, tmp); + comp = (*t->t_compare)(elm, node); + if (comp < 0) + tmp = RBE_LEFT(tmp); + else if (comp > 0) + tmp = RBE_RIGHT(tmp); + else + return (node); + } + + rbe_set(rbe, parent); + + if (parent != NULL) { + if (comp < 0) + RBE_LEFT(parent) = rbe; + else + RBE_RIGHT(parent) = rbe; + + rbe_if_augment(t, parent); + } else + RBH_ROOT(rbt) = rbe; + + rbe_insert_color(t, rbt, rbe); + + return NULL; +} + +/* Finds the node with the same key as elm */ +void *_rb_find(const struct rb_type *t, const struct rbt_tree *rbt, + const void *key) +{ + struct rb_entry *tmp = RBH_ROOT(rbt); + void *node; + int comp; + + while (tmp != NULL) { + node = rb_e2n(t, tmp); + comp = (*t->t_compare)(key, node); + if (comp < 0) + tmp = RBE_LEFT(tmp); + else if (comp > 0) + tmp = RBE_RIGHT(tmp); + else + return (node); + } + + return NULL; +} + +/* Finds the first node greater than or equal to the search key */ +void *_rb_nfind(const struct rb_type *t, const struct rbt_tree *rbt, + const void *key) +{ + struct rb_entry *tmp = RBH_ROOT(rbt); + void *node; + void *res = NULL; + int comp; + + while (tmp != NULL) { + node = rb_e2n(t, tmp); + comp = (*t->t_compare)(key, node); + if (comp < 0) { + res = node; + tmp = RBE_LEFT(tmp); + } else if (comp > 0) + tmp = RBE_RIGHT(tmp); + else + return (node); + } + + return (res); +} + +void *_rb_next(const struct rb_type *t, void *elm) +{ + struct rb_entry *rbe = rb_n2e(t, elm); + + if (RBE_RIGHT(rbe) != NULL) { + rbe = RBE_RIGHT(rbe); + while (RBE_LEFT(rbe) != NULL) + rbe = RBE_LEFT(rbe); + } else { + if (RBE_PARENT(rbe) && (rbe == RBE_LEFT(RBE_PARENT(rbe)))) + rbe = RBE_PARENT(rbe); + else { + while (RBE_PARENT(rbe) + && (rbe == RBE_RIGHT(RBE_PARENT(rbe)))) + rbe = RBE_PARENT(rbe); + rbe = RBE_PARENT(rbe); + } + } + + return (rbe == NULL ? NULL : rb_e2n(t, rbe)); +} + +void *_rb_prev(const struct rb_type *t, void *elm) +{ + struct rb_entry *rbe = rb_n2e(t, elm); + + if (RBE_LEFT(rbe)) { + rbe = RBE_LEFT(rbe); + while (RBE_RIGHT(rbe)) + rbe = RBE_RIGHT(rbe); + } else { + if (RBE_PARENT(rbe) && (rbe == RBE_RIGHT(RBE_PARENT(rbe)))) + rbe = RBE_PARENT(rbe); + else { + while (RBE_PARENT(rbe) + && (rbe == RBE_LEFT(RBE_PARENT(rbe)))) + rbe = RBE_PARENT(rbe); + rbe = RBE_PARENT(rbe); + } + } + + return (rbe == NULL ? NULL : rb_e2n(t, rbe)); +} + +void *_rb_root(const struct rb_type *t, const struct rbt_tree *rbt) +{ + struct rb_entry *rbe = RBH_ROOT(rbt); + + return (rbe == NULL ? rbe : rb_e2n(t, rbe)); +} + +void *_rb_min(const struct rb_type *t, const struct rbt_tree *rbt) +{ + struct rb_entry *rbe = RBH_ROOT(rbt); + struct rb_entry *parent = NULL; + + while (rbe != NULL) { + parent = rbe; + rbe = RBE_LEFT(rbe); + } + + return (parent == NULL ? NULL : rb_e2n(t, parent)); +} + +void *_rb_max(const struct rb_type *t, const struct rbt_tree *rbt) +{ + struct rb_entry *rbe = RBH_ROOT(rbt); + struct rb_entry *parent = NULL; + + while (rbe != NULL) { + parent = rbe; + rbe = RBE_RIGHT(rbe); + } + + return (parent == NULL ? NULL : rb_e2n(t, parent)); +} + +void *_rb_left(const struct rb_type *t, void *node) +{ + struct rb_entry *rbe = rb_n2e(t, node); + rbe = RBE_LEFT(rbe); + return (rbe == NULL ? NULL : rb_e2n(t, rbe)); +} + +void *_rb_right(const struct rb_type *t, void *node) +{ + struct rb_entry *rbe = rb_n2e(t, node); + rbe = RBE_RIGHT(rbe); + return (rbe == NULL ? NULL : rb_e2n(t, rbe)); +} + +void *_rb_parent(const struct rb_type *t, void *node) +{ + struct rb_entry *rbe = rb_n2e(t, node); + rbe = RBE_PARENT(rbe); + return (rbe == NULL ? NULL : rb_e2n(t, rbe)); +} + +void _rb_set_left(const struct rb_type *t, void *node, void *left) +{ + struct rb_entry *rbe = rb_n2e(t, node); + struct rb_entry *rbl = (left == NULL) ? NULL : rb_n2e(t, left); + + RBE_LEFT(rbe) = rbl; +} + +void _rb_set_right(const struct rb_type *t, void *node, void *right) +{ + struct rb_entry *rbe = rb_n2e(t, node); + struct rb_entry *rbr = (right == NULL) ? NULL : rb_n2e(t, right); + + RBE_RIGHT(rbe) = rbr; +} + +void _rb_set_parent(const struct rb_type *t, void *node, void *parent) +{ + struct rb_entry *rbe = rb_n2e(t, node); + struct rb_entry *rbp = (parent == NULL) ? NULL : rb_n2e(t, parent); + + RBE_PARENT(rbe) = rbp; +} + +void _rb_poison(const struct rb_type *t, void *node, unsigned long poison) +{ + struct rb_entry *rbe = rb_n2e(t, node); + + RBE_PARENT(rbe) = RBE_LEFT(rbe) = RBE_RIGHT(rbe) = + (struct rb_entry *)poison; +} + +int _rb_check(const struct rb_type *t, void *node, unsigned long poison) +{ + struct rb_entry *rbe = rb_n2e(t, node); + + return ((unsigned long)RBE_PARENT(rbe) == poison + && (unsigned long)RBE_LEFT(rbe) == poison + && (unsigned long)RBE_RIGHT(rbe) == poison); +} |