1 /* 2 Red Black Trees 3 (C) 1999 Andrea Arcangeli <andrea@suse.de> 4 5 This program is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by 7 the Free Software Foundation; either version 2 of the License, or 8 (at your option) any later version. 9 10 This program is distributed in the hope that it will be useful, 11 but WITHOUT ANY WARRANTY; without even the implied warranty of 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 GNU General Public License for more details. 14 15 You should have received a copy of the GNU General Public License 16 along with this program; if not, write to the Free Software 17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 19 linux/include/linux/rbtree.h 20 21 To use rbtrees you'll have to implement your own insert and search cores. 22 This will avoid us to use callbacks and to drop drammatically performances. 23 I know it's not the cleaner way, but in C (not in C++) to get 24 performances and genericity... 25 26 See Documentation/rbtree.txt for documentation and samples. 27 */ 28 29 #ifndef _LINUX_RBTREE_H 30 #define _LINUX_RBTREE_H 31 32 #include <linux/kernel.h> 33 #include <linux/stddef.h> 34 35 struct rb_node { 36 unsigned long __rb_parent_color; 37 struct rb_node *rb_right; 38 struct rb_node *rb_left; 39 } __attribute__((aligned(sizeof(long)))); 40 /* The alignment might seem pointless, but allegedly CRIS needs it */ 41 42 struct rb_root { 43 struct rb_node *rb_node; 44 }; 45 46 47 #define rb_parent(r) ((struct rb_node *)((r)->__rb_parent_color & ~3)) 48 49 #define RB_ROOT (struct rb_root) { NULL, } 50 #define rb_entry(ptr, type, member) container_of(ptr, type, member) 51 52 #define RB_EMPTY_ROOT(root) ((root)->rb_node == NULL) 53 54 /* 'empty' nodes are nodes that are known not to be inserted in an rbree */ 55 #define RB_EMPTY_NODE(node) \ 56 ((node)->__rb_parent_color == (unsigned long)(node)) 57 #define RB_CLEAR_NODE(node) \ 58 ((node)->__rb_parent_color = (unsigned long)(node)) 59 60 61 extern void rb_insert_color(struct rb_node *, struct rb_root *); 62 extern void rb_erase(struct rb_node *, struct rb_root *); 63 64 65 /* Find logical next and previous nodes in a tree */ 66 extern struct rb_node *rb_next(const struct rb_node *); 67 extern struct rb_node *rb_prev(const struct rb_node *); 68 extern struct rb_node *rb_first(const struct rb_root *); 69 extern struct rb_node *rb_last(const struct rb_root *); 70 71 /* Fast replacement of a single node without remove/rebalance/add/rebalance */ 72 extern void rb_replace_node(struct rb_node *victim, struct rb_node *new, 73 struct rb_root *root); 74 75 static inline void rb_link_node(struct rb_node * node, struct rb_node * parent, 76 struct rb_node ** rb_link) 77 { 78 node->__rb_parent_color = (unsigned long)parent; 79 node->rb_left = node->rb_right = NULL; 80 81 *rb_link = node; 82 } 83 84 #endif /* _LINUX_RBTREE_H */ 85