『Linux内核红黑树之通用红黑树』Linux内核红黑树+C99弹性结构体封装 - Chinaunix

/*
Red Black Trees
(C) 1999 Andrea Arcangeli <andrea@suse.de>
(C) 2002 David Woodhouse <dwmw2@infradead.org>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
linux/lib/rbtree.c
*/
#include "rbtree.h"
//#include <linux/module.h>
static void __rb_rotate_left(struct rb_node *node, struct rb_root *root)
{
struct rb_node *right = node->rb_right;
struct rb_node *parent = rb_parent(node);
if ((node->rb_right = right->rb_left))
rb_set_parent(right->rb_left, node);
right->rb_left = node;
rb_set_parent(right, parent);
if (parent)
{
if (node == parent->rb_left)
parent->rb_left = right;
else
parent->rb_right = right;
}
else
root->rb_node = right;
rb_set_parent(node, right);
}
static void __rb_rotate_right(struct rb_node *node, struct rb_root *root)
{
struct rb_node *left = node->rb_left;
struct rb_node *parent = rb_parent(node);
if ((node->rb_left = left->rb_right))
rb_set_parent(left->rb_right, node);
left->rb_right = node;
rb_set_parent(left, parent);
if (parent)
{
if (node == parent->rb_right)
parent->rb_right = left;
else
parent->rb_left = left;
}
else
root->rb_node = left;
rb_set_parent(node, left);
}
void rb_insert_color(struct rb_node *node, struct rb_root *root)
{
struct rb_node *parent, *gparent;
while ((parent = rb_parent(node)) && rb_is_red(parent))
{
gparent = rb_parent(parent);
if (parent == gparent->rb_left)
{
{
register struct rb_node *uncle = gparent->rb_right;
if (uncle && rb_is_red(uncle))
{
rb_set_black(uncle);
rb_set_black(parent);
rb_set_red(gparent);
node = gparent;
continue;
}
}
if (parent->rb_right == node)
{
register struct rb_node *tmp;
__rb_rotate_left(parent, root);
tmp = parent;
parent = node;
node = tmp;
}
rb_set_black(parent);
rb_set_red(gparent);
__rb_rotate_right(gparent, root);
} else {
{
register struct rb_node *uncle = gparent->rb_left;
if (uncle && rb_is_red(uncle))
{
rb_set_black(uncle);
rb_set_black(parent);
rb_set_red(gparent);
node = gparent;
continue;
}
}
if (parent->rb_left == node)
{
register struct rb_node *tmp;
__rb_rotate_right(parent, root);
tmp = parent;
parent = node;
node = tmp;
}
rb_set_black(parent);
rb_set_red(gparent);
__rb_rotate_left(gparent, root);
}
}
rb_set_black(root->rb_node);
}
//EXPORT_SYMBOL(rb_insert_color);
static void __rb_erase_color(struct rb_node *node, struct rb_node *parent,
struct rb_root *root)
{
struct rb_node *other;
while ((!node || rb_is_black(node)) && node != root->rb_node)
{
if (parent->rb_left == node)
{
other = parent->rb_right;
if (rb_is_red(other))
{
rb_set_black(other);
rb_set_red(parent);
__rb_rotate_left(parent, root);
other = parent->rb_right;
}
if ((!other->rb_left || rb_is_black(other->rb_left)) &&
(!other->rb_right || rb_is_black(other->rb_right)))
{
rb_set_red(other);
node = parent;
parent = rb_parent(node);
}
else
{
if (!other->rb_right || rb_is_black(other->rb_right))
{
rb_set_black(other->rb_left);
rb_set_red(other);
__rb_rotate_right(other, root);
other = parent->rb_right;
}
rb_set_color(other, rb_color(parent));
rb_set_black(parent);
rb_set_black(other->rb_right);
__rb_rotate_left(parent, root);
node = root->rb_node;
break;
}
}
else
{
other = parent->rb_left;
if (rb_is_red(other))
{
rb_set_black(other);
rb_set_red(parent);
__rb_rotate_right(parent, root);
other = parent->rb_left;
}
if ((!other->rb_left || rb_is_black(other->rb_left)) &&
(!other->rb_right || rb_is_black(other->rb_right)))
{
rb_set_red(other);
node = parent;
parent = rb_parent(node);
}
else
{
if (!other->rb_left || rb_is_black(other->rb_left))
{
rb_set_black(other->rb_right);
rb_set_red(other);
__rb_rotate_left(other, root);
other = parent->rb_left;
}
rb_set_color(other, rb_color(parent));
rb_set_black(parent);
rb_set_black(other->rb_left);
__rb_rotate_right(parent, root);
node = root->rb_node;
break;
}
}
}
if (node)
rb_set_black(node);
}
void rb_erase(struct rb_node *node, struct rb_root *root)
{
struct rb_node *child, *parent;
int color;
if (!node->rb_left)
child = node->rb_right;
else if (!node->rb_right)
child = node->rb_left;
else
{
struct rb_node *old = node, *left;
node = node->rb_right;
while ((left = node->rb_left) != NULL)
node = left;
if (rb_parent(old)) {
if (rb_parent(old)->rb_left == old)
rb_parent(old)->rb_left = node;
else
rb_parent(old)->rb_right = node;
} else
root->rb_node = node;
child = node->rb_right;
parent = rb_parent(node);
color = rb_color(node);
if (parent == old) {
parent = node;
} else {
if (child)
rb_set_parent(child, parent);
parent->rb_left = child;
node->rb_right = old->rb_right;
rb_set_parent(old->rb_right, node);
}
node->rb_parent_color = old->rb_parent_color;
node->rb_left = old->rb_left;
rb_set_parent(old->rb_left, node);
goto color;
}
parent = rb_parent(node);
color = rb_color(node);
if (child)
rb_set_parent(child, parent);
if (parent)
{
if (parent->rb_left == node)
parent->rb_left = child;
else
parent->rb_right = child;
}
else
root->rb_node = child;
color:
if (color == RB_BLACK)
__rb_erase_color(child, parent, root);
}
//EXPORT_SYMBOL(rb_erase);
static void rb_augment_path(struct rb_node *node, rb_augment_f func, void *data)
{
struct rb_node *parent;
up:
func(node, data);
parent = rb_parent(node);
if (!parent)
return;
if (node == parent->rb_left && parent->rb_right)
func(parent->rb_right, data);
else if (parent->rb_left)
func(parent->rb_left, data);
node = parent;
goto up;
}
/*
* after inserting @node into the tree, update the tree to account for
* both the new entry and any damage done by rebalance
*/
void rb_augment_insert(struct rb_node *node, rb_augment_f func, void *data)
{
if (node->rb_left)
node = node->rb_left;
else if (node->rb_right)
node = node->rb_right;
rb_augment_path(node, func, data);
}
/*
* before removing the node, find the deepest node on the rebalance path
* that will still be there after @node gets removed
*/
struct rb_node *rb_augment_erase_begin(struct rb_node *node)
{
struct rb_node *deepest;
if (!node->rb_right && !node->rb_left)
deepest = rb_parent(node);
else if (!node->rb_right)
deepest = node->rb_left;
else if (!node->rb_left)
deepest = node->rb_right;
else {
deepest = rb_next(node);
if (deepest->rb_right)
deepest = deepest->rb_right;
else if (rb_parent(deepest) != node)
deepest = rb_parent(deepest);
}
return deepest;
}
/*
* after removal, update the tree to account for the removed entry
* and any rebalance damage.
*/
void rb_augment_erase_end(struct rb_node *node, rb_augment_f func, void *data)
{
if (node)
rb_augment_path(node, func, data);
}
/*
* This function returns the first node (in sort order) of the tree.
*/
struct rb_node *rb_first(const struct rb_root *root)
{
struct rb_node *n;
n = root->rb_node;
if (!n)
return NULL;
while (n->rb_left)
n = n->rb_left;
return n;
}
//EXPORT_SYMBOL(rb_first);
struct rb_node *rb_last(const struct rb_root *root)
{
struct rb_node *n;
n = root->rb_node;
if (!n)
return NULL;
while (n->rb_right)
n = n->rb_right;
return n;
}
//EXPORT_SYMBOL(rb_last);
struct rb_node *rb_next(const struct rb_node *node)
{
struct rb_node *parent;
if (rb_parent(node) == node)
return NULL;
/* If we have a right-hand child, go down and then left as far
as we can. */
if (node->rb_right) {
node = node->rb_right;
while (node->rb_left)
node=node->rb_left;
return (struct rb_node *)node;
}
/* No right-hand children. Everything down and left is
smaller than us, so any 'next' node must be in the general
direction of our parent. Go up the tree; any time the
ancestor is a right-hand child of its parent, keep going
up. First time it's a left-hand child of its parent, said
parent is our 'next' node. */
while ((parent = rb_parent(node)) && node == parent->rb_right)
node = parent;
return parent;
}
//EXPORT_SYMBOL(rb_next);
struct rb_node *rb_prev(const struct rb_node *node)
{
struct rb_node *parent;
if (rb_parent(node) == node)
return NULL;
/* If we have a left-hand child, go down and then right as far
as we can. */
if (node->rb_left) {
node = node->rb_left;
while (node->rb_right)
node=node->rb_right;
return (struct rb_node *)node;
}
/* No left-hand children. Go up till we find an ancestor which
is a right-hand child of its parent */
while ((parent = rb_parent(node)) && node == parent->rb_left)
node = parent;
return parent;
}
//EXPORT_SYMBOL(rb_prev);
void rb_replace_node(struct rb_node *victim, struct rb_node *new,
struct rb_root *root)
{
struct rb_node *parent = rb_parent(victim);
/* Set the surrounding nodes to point to the replacement */
if (parent) {
if (victim == parent->rb_left)
parent->rb_left = new;
else
parent->rb_right = new;
} else {
root->rb_node = new;
}
if (victim->rb_left)
rb_set_parent(victim->rb_left, new);
if (victim->rb_right)
rb_set_parent(victim->rb_right, new);
/* Copy the pointers/colour from the victim to the replacement */
*new = *victim;
}
//EXPORT_SYMBOL(rb_replace_node);

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#ifndef _LINUX_RBTREE_H
#define _LINUX_RBTREE_H
//#include <linux/kernel.h>
//#include <linux/stddef.h>
#include <stddef.h>
struct rb_node
{
unsigned long rb_parent_color;
#define RB_RED 0
#define RB_BLACK 1
struct rb_node *rb_right;
struct rb_node *rb_left;
} __attribute__((aligned(sizeof(long))));
/* The alignment might seem pointless, but allegedly CRIS needs it */
struct rb_root
{
struct rb_node *rb_node;
};
#define rb_parent(r) ((struct rb_node *)((r)->rb_parent_color & ~3))
#define rb_color(r) ((r)->rb_parent_color & 1)
#define rb_is_red(r) (!rb_color(r))
#define rb_is_black(r) rb_color(r)
#define rb_set_red(r) do { (r)->rb_parent_color &= ~1; } while (0)
#define rb_set_black(r) do { (r)->rb_parent_color |= 1; } while (0)
static
inline void rb_set_parent(struct rb_node *rb, struct rb_node *p)
{
rb->rb_parent_color = (rb->rb_parent_color & 3) | (unsigned long)p;
}
static
inline void rb_set_color(struct rb_node *rb, int color)
{
rb->rb_parent_color = (rb->rb_parent_color & ~1) | color;
}
/**********************************************************/
#ifndef offsetof
#define offsetof(type, member) \
(size_t)&(((type *)0)->member)
#endif
#ifndef container_of
#define container_of(ptr, type, member) \
({\
const typeof(((type *)0)->member) * __mptr = (ptr);\
(type *)((char *)__mptr - offsetof(type, member)); \
})
#endif
/**********************************************************/
#define RB_ROOT (struct rb_root) { NULL, }
#define rb_entry(ptr, type, member) container_of(ptr, type, member)
#define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL)
#define RB_EMPTY_NODE(node) (rb_parent(node) == node)
#define RB_CLEAR_NODE(node) (rb_set_parent(node, node))
extern void rb_insert_color(struct rb_node *, struct rb_root *);
extern void rb_erase(struct rb_node *, struct rb_root *);
typedef void (*rb_augment_f)(struct rb_node *node, void *data);
extern void rb_augment_insert(struct rb_node *node,
rb_augment_f func, void *data);
extern struct rb_node *rb_augment_erase_begin(struct rb_node *node);
extern void rb_augment_erase_end(struct rb_node *node,
rb_augment_f func, void *data);
/* Find logical next and previous nodes in a tree */
extern struct rb_node *rb_next(const struct rb_node *);
extern struct rb_node *rb_prev(const struct rb_node *);
extern struct rb_node *rb_first(const struct rb_root *);
extern struct rb_node *rb_last(const struct rb_root *);
/* Fast replacement of a single node without remove/rebalance/add/rebalance */
extern void rb_replace_node(struct rb_node *victim, struct rb_node *new,
struct rb_root *root);
static
inline void rb_link_node(struct rb_node * node, struct rb_node * parent,
struct rb_node ** rb_link)
{
node->rb_parent_color = (unsigned long )parent;
node->rb_left = node->rb_right = NULL;
*rb_link = node;
}
#endif /* _LINUX_RBTREE_H */

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#ifndef __RCYH_RBTREE_RC_H__
#define __RCYH_RBTREE_RC_H__
#include "rbtree.h"
struct rb_data
{
signed long key;
unsigned long size;
unsigned char data[];
};
struct container
{
struct rb_node rb_node;
struct rb_data rb_data;
};
/*
* Initializing rbtree root
*/
extern void
init_rbtree(struct rb_root *root);
/*
* Search key node from rbtree
*/
extern struct container *
container_search(struct rb_root *root, int key);
/*
* Insert key node into rbtree
*/
extern int
container_insert(struct rb_root *root, struct container *cont);
/*
* Delete the key node from rbtree
* delete node from rbtree, return node pointer
*/
extern struct container *
container_delete(struct rb_root *root, int key);
/*
* Replace the key node from rbtree for new container
* replace node from rbtree, return old node pointer
*/
struct container *
container_replace(struct rb_root *root, int key, struct container *con);
#endif /* __RCYH_RBTREE_RC_H__ */

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#include "rbtree_rc.h"
#include <stddef.h>
/*
* Initializing rbtree root
*/
void init_rbtree(struct rb_root *root)
{
*root = RB_ROOT;
}
/*
* Search key node from rbtree
*/
struct container *container_search(struct rb_root *root, int key)
{
struct rb_node *node = root->rb_node;
while (node)
{
struct container *this = rb_entry(node, struct container, rb_node);
int result = key - this->rb_data.key;
if (result < 0)
node = node->rb_left;
else if (result > 0)
node = node->rb_right;
else
return this;
}
return 0;
}
/*
* Insert key node into rbtree
*/
int container_insert(struct rb_root *root, struct container *cont)
{
struct rb_node **new = &(root->rb_node);
struct rb_node *parent = 0;
/* Figure out where to put new node */
while (*new)
{
struct container *this = rb_entry(*new, struct container, rb_node);
int result = cont->rb_data.key - this->rb_data.key;
parent = *new;
if (result < 0)
new = &((*new)->rb_left);
else if (result > 0)
new = &((*new)->rb_right);
else
return -1; // the key is already exists
}
/* Add new node and rebalance tree. */
rb_link_node(&(cont->rb_node), parent, new);
rb_insert_color(&(cont->rb_node), root);
return 0;
}
/*
* Delete the key node from rbtree
* delete node from rbtree, return node pointer
*/
struct container *container_delete(struct rb_root *root, int key)
{
struct container *find = container_search(root, key);
if (!find)
return 0;
rb_erase(&find->rb_node, root);
return find;
}
/*
* Replace the key node from rbtree for new container
* replace node from rbtree, return old node pointer
*/
struct container * container_replace(struct rb_root *root, int key, struct container *con)
{
struct container *find = container_search(root, key);
if (!find)
return 0;
rb_replace_node(&(find->rb_node), &con->rb_node, root);
return find;
}

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#include "rbtree_rc.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
int
main(void)
{
struct rb_root mytree = RB_ROOT;
struct container * pc;
int ret;
int size = 100;
int find, erase, replace;
printf("rbtest go ... \n");
/*
* 插入测试
*/
pc = calloc(sizeof(struct container) + size, 1);
strcat((char*)&pc->rb_data.data, "hello world 1");
pc -> rb_data.key = 1;
pc -> rb_data.size = size;
ret = container_insert(&mytree, pc);
printf("insert 1 ret = %d\n", ret);
pc = calloc(sizeof(struct container) + size, 1);
strcat((char*)&pc->rb_data.data, "hello world 2");
pc -> rb_data.key = 2;
pc -> rb_data.size = size;
ret = container_insert(&mytree, pc);
printf("insert 2 ret = %d\n", ret);
pc = calloc(sizeof(struct container) + size, 1);
strcat((char*)&pc->rb_data.data, "hello world 4");
pc -> rb_data.key = 4;
pc -> rb_data.size = size;
ret = container_insert(&mytree, pc);
printf("insert 4 ret = %d\n", ret);
pc = calloc(sizeof(struct container) + size, 1);
strcat((char*)&pc->rb_data.data, "hello world 3");
pc -> rb_data.key = 3;
pc -> rb_data.size = size;
ret = container_insert(&mytree, pc);
printf("insert 3 ret = %d\n", ret);
/********************************************************/
/*
* 查找测试
*/
find = 6;
printf("find key %d\n", find);
pc = container_search(&mytree, find);
if (pc != 0)
printf("key %d pc data: %s\n", find, (char*)pc->rb_data.data);
else
printf("no find %d\n", find);
find = 3;
printf("find key %d\n", find);
pc = container_search(&mytree, find);
if (pc != 0)
printf("find key %d data: %s\n", find, (char*)pc->rb_data.data);
else
printf("no find %d\n", find);
/********************************************************/
/*
* 节点删除测试
*/
erase = 3;
printf("erase key %d\n", erase);
pc = container_delete(&mytree, erase);
if (pc != 0) {
printf("erase key %d data: %s\n", find, (char*)pc->rb_data.data);
free(pc);
}
else
printf("no erase %d\n", find);
find = 3;
printf("find key %d\n", find);
pc = container_search(&mytree, find);
if (pc != 0)
printf("find key %d data: %s\n", find, (char*)pc->rb_data.data);
else
printf("no find %d\n", find);
/********************************************************/
/*
* 节点更新替换测试
*/
replace = 2;
printf("replace key %d\n", replace);
pc = calloc(sizeof(struct container) + size, 1);
strcat((char*)&pc->rb_data.data, "this is replace key 2");
pc -> rb_data.key = replace;
pc -> rb_data.size = size;
pc = container_replace(&mytree, replace, pc);
if (pc != 0)
{
printf("replace key %d ret = %p, data: %s\n", replace, pc, (char*)pc->rb_data.data);
free(pc);
}
else
{
printf("replace key %d failed\n", replace);
}
find = 2;
printf("find key %d\n", find);
pc = container_search(&mytree, find);
if (pc != 0)
printf("find key %d data: %s\n", find, (char*)pc->rb_data.data);
else
printf("no find %d\n", find);
/********************************************************/
printf("rbtest end\n");
return 0;
}

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