+++ /dev/null
-/*
- Red Black Trees
- (C) 1999 Andrea Arcangeli <andrea@suse.de>
-
- 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/include/linux/rbtree.h
-
- To use rbtrees you'll have to implement your own insert and search cores.
- This will avoid us to use callbacks and to drop drammatically performances.
- I know it's not the cleaner way, but in C (not in C++) to get
- performances and genericity...
-
- Some example of insert and search follows here. The search is a plain
- normal search over an ordered tree. The insert instead must be implemented
- int two steps: as first thing the code must insert the element in
- order as a red leaf in the tree, then the support library function
- rb_insert_color() must be called. Such function will do the
- not trivial work to rebalance the rbtree if necessary.
-
------------------------------------------------------------------------
-static inline struct page * rb_search_page_cache(struct inode * inode,
- unsigned long offset)
-{
- struct rb_node * n = inode->i_rb_page_cache.rb_node;
- struct page * page;
-
- while (n)
- {
- page = rb_entry(n, struct page, rb_page_cache);
-
- if (offset < page->offset)
- n = n->rb_left;
- else if (offset > page->offset)
- n = n->rb_right;
- else
- return page;
- }
- return NULL;
-}
-
-static inline struct page * __rb_insert_page_cache(struct inode * inode,
- unsigned long offset,
- struct rb_node * node)
-{
- struct rb_node ** p = &inode->i_rb_page_cache.rb_node;
- struct rb_node * parent = NULL;
- struct page * page;
-
- while (*p)
- {
- parent = *p;
- page = rb_entry(parent, struct page, rb_page_cache);
-
- if (offset < page->offset)
- p = &(*p)->rb_left;
- else if (offset > page->offset)
- p = &(*p)->rb_right;
- else
- return page;
- }
-
- rb_link_node(node, parent, p);
-
- return NULL;
-}
-
-static inline struct page * rb_insert_page_cache(struct inode * inode,
- unsigned long offset,
- struct rb_node * node)
-{
- struct page * ret;
- if ((ret = __rb_insert_page_cache(inode, offset, node)))
- goto out;
- rb_insert_color(node, &inode->i_rb_page_cache);
- out:
- return ret;
-}
------------------------------------------------------------------------
-*/
-
-/** \file rbtree.h Exported symbols from rbtree.h */
-
-#ifndef _LINUX_RBTREE_H
-#define _LINUX_RBTREE_H
-
-
-/** get the struct this entry is embedded in */
-#define container_of(ptr, type, member) ({ \
- const typeof( ((type *)0)->member ) *__mptr = (ptr); \
- (type *)( (char *)__mptr - offsetof(type,member) );})
-
-
-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;
- unsigned size;
-} __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;
-}
-
-#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 *);
-
-/* 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 *);
-
-extern struct rb_node *rb_nth(const struct rb_node *node, unsigned n);
-extern int rb_rank(const struct rb_node *node, unsigned *rank);
-
-/* 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->size = 1;
- node->rb_parent_color = (unsigned long )parent;
- node->rb_left = node->rb_right = NULL;
-
- *rb_link = node;
- /* Fixup the size fields in the tree */
- while ((node = rb_parent(node)))
- node->size++;
-}
-
-#endif /* _LINUX_RBTREE_H */
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