/* Red Black Trees (C) 1999 Andrea Arcangeli 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... See Documentation/rbtree.txt for documentation and samples. */ #ifndef _LINUX_RBTREE_H #define _LINUX_RBTREE_H #include typedef struct rb_node { unsigned long __rb_parent_color; struct rb_node *rb_right; struct rb_node *rb_left; } rb_node_t; typedef struct rb_root { struct rb_node *rb_node; } rb_root_t; /* * Leftmost-cached rbtrees. * * We do not cache the rightmost node based on footprint * size vs number of potential users that could benefit * from O(1) rb_last(). Just not worth it, users that want * this feature can always implement the logic explicitly. * Furthermore, users that want to cache both pointers may * find it a bit asymmetric, but that's ok. */ typedef struct rb_root_cached { struct rb_root rb_root; struct rb_node *rb_leftmost; } rb_root_cached_t; /* Copy from linux kernel 2.6 source (kernel.h, stddef.h) */ #ifndef container_of # define container_of(ptr, type, member) ({ \ const typeof( ((type *)0)->member ) *__mptr = (ptr); \ (type *)( (char *)__mptr - offsetof(type,member) );}) #endif #ifndef offsetof # define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) #endif #define rb_parent(r) ((struct rb_node *)((r)->__rb_parent_color & ~3)) #define RB_ROOT (struct rb_root) { NULL, } #define RB_ROOT_CACHED (struct rb_root_cached) { {NULL, }, NULL } #define rb_entry(ptr, type, member) container_of(ptr, type, member) #define RB_EMPTY_ROOT(root) (((root)->rb_node) == NULL) /* 'empty' nodes are nodes that are known not to be inserted in an rbtree */ #define RB_EMPTY_NODE(node) \ ((node)->__rb_parent_color == (unsigned long)(node)) #define RB_CLEAR_NODE(node) \ ((node)->__rb_parent_color = (unsigned long)(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 void rb_insert_color_cached(struct rb_node *, struct rb_root_cached *, bool); extern void rb_erase_cached(struct rb_node *node, struct rb_root_cached *); /* Same as rb_first(), but O(1) */ #define rb_first_cached(root) (root)->rb_leftmost /* Postorder iteration - always visit the parent after its children */ extern struct rb_node *rb_first_postorder(const struct rb_root *); extern struct rb_node *rb_next_postorder(const struct rb_node *); /* 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); extern void rb_replace_node_rcu(struct rb_node *victim, struct rb_node *new, struct rb_root *root); extern void rb_replace_node_cached(struct rb_node *victim, struct rb_node *new, struct rb_root_cached *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; } #ifdef UNUSED_CODE static inline void rb_link_node_rcu(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; rcu_assign_pointer(*rb_link, node); } #endif #define rb_entry_safe(ptr, type, member) \ ({ typeof(ptr) ____ptr = (ptr); \ ____ptr ? rb_entry(____ptr, type, member) : NULL; \ }) /** * rbtree_postorder_for_each_entry_safe - iterate in post-order over rb_root of * given type allowing the backing memory of @pos to be invalidated * * @pos: the 'type *' to use as a loop cursor. * @n: another 'type *' to use as temporary storage * @root: 'rb_root *' of the rbtree. * @field: the name of the rb_node field within 'type'. * * rbtree_postorder_for_each_entry_safe() provides a similar guarantee as * list_for_each_entry_safe() and allows the iteration to continue independent * of changes to @pos by the body of the loop. * * Note, however, that it cannot handle other modifications that re-order the * rbtree it is iterating over. This includes calling rb_erase() on @pos, as * rb_erase() may rebalance the tree, causing us to miss some nodes. */ #define rbtree_postorder_for_each_entry_safe(pos, n, root, field) \ for (pos = rb_entry_safe(rb_first_postorder(root), typeof(*pos), field); \ pos && ({ n = rb_entry_safe(rb_next_postorder(&pos->field), \ typeof(*pos), field); 1; }); \ pos = n) /* The following are keepalived specific code */ /** * rb_search - Search for a specific value in rbtree * @root: the rbtree root. * @key: the key to seach for in your rbtree. * @member: the name of the rb_node within the struct. * @compar: the name of the comparison function to use. */ #define rb_search(root, key, member, compar) \ ({ \ rb_node_t *__n = (root)->rb_node; \ typeof(key) __ret = NULL, __data; \ \ while (__n) { \ __data = rb_entry(__n, typeof(*key), member); \ int __cmp = compar(key, __data); \ \ if (__cmp < 0) \ __n = __n->rb_left; \ else if (__cmp > 0) \ __n = __n->rb_right; \ else { \ __ret = __data; \ break; \ } \ } \ __ret; \ }) /** * rb_search_first - Search for the first greater value in rbtree * @root: the rbtree root. * @key: the key to seach for in your rbtree. * @member: the name of the rb_node within the struct. * @compar: the name of the comparison function to use. */ #define rb_search_first(root, key, member, compar) \ ({ \ rb_node_t *__n = (root)->rb_node; \ typeof(key) __ret = NULL, __data; \ \ while (__n) { \ __data = rb_entry(__n, typeof(*key), member); \ int __cmp = compar(key, __data); \ \ if (__cmp < 0) { \ __ret = __data; \ __n = __n->rb_left; \ } else if (__cmp > 0) \ __n = __n->rb_right; \ else { \ __ret = __data; \ break; \ } \ } \ if (!__ret && !RB_EMPTY_ROOT(root)) \ __ret = rb_entry(rb_first(root), typeof(*key), member); \ __ret; \ }) /** * rb_insert - Insert a new node into your rbtree * @root: the rbtree root. * @new: the node to insert. * @member: the name of the rb_node within the struct. * @compar: the name of the comparison function to use. */ #define rb_insert(root, new, member, compar) \ ({ \ rb_node_t **__n = &(root)->rb_node, *__parent = NULL; \ typeof(new) __old = NULL, __data; \ \ while (*__n) { \ __data = rb_entry(*__n, typeof(*new), member); \ int __cmp = compar(new, __data); \ \ __parent = *__n; \ if (__cmp < 0) \ __n = &((*__n)->rb_left); \ else if (__cmp > 0) \ __n = &((*__n)->rb_right); \ else { \ __old = __data; \ break; \ } \ } \ \ if (__old == NULL) { \ /* Add new node and rebalance tree. */ \ rb_link_node(&((new)->member), __parent, __n); \ rb_insert_color(&((new)->member), root); \ } \ \ __old; \ }) /** * rb_insert - Insert & Sort a new node into your rbtree * @root: the rbtree root. * @new: the node to insert. * @member: the name of the rb_node within the struct. * @compar: the name of the comparison function to use. */ #define rb_insert_sort(root, new, member, compar) \ ({ \ rb_node_t **__n = &(root)->rb_node, *__parent = NULL; \ typeof(new) __data; \ \ while (*__n) { \ __data = rb_entry(*__n, typeof(*new), member); \ int __cmp = compar(new, __data); \ \ __parent = *__n; \ if (__cmp <= 0) \ __n = &((*__n)->rb_left); \ else if (__cmp > 0) \ __n = &((*__n)->rb_right); \ } \ \ /* Add new node and rebalance tree. */ \ rb_link_node(&((new)->member), __parent, __n); \ rb_insert_color(&((new)->member), root); \ }) /** * rb_insert_cached - Insert & Sort a new node into your cached rbtree * @root: the rbtree root. * @new: the node to insert. * @member: the name of the rb_node within the struct. * @compar: the name of the comparison function to use. */ #define rb_insert_sort_cached(root, new, member, compar) \ ({ \ rb_node_t **__n = &(root)->rb_root.rb_node, *__parent = NULL; \ typeof(new) __data; \ \ while (*__n) { \ __data = rb_entry(*__n, typeof(*new), member); \ int __cmp = compar(new, __data); \ \ __parent = *__n; \ if (__cmp <= 0) \ __n = &((*__n)->rb_left); \ else if (__cmp > 0) \ __n = &((*__n)->rb_right); \ } \ /* Add new node and rebalance tree. */ \ rb_link_node(&((new)->member), __parent, __n); \ rb_insert_color_cached(&((new)->member), root, \ !(root)->rb_leftmost || __n == &(root)->rb_leftmost->rb_left); \ }) /** * rb_for_each_entry - Iterate over rbtree of given type * @pos: the type * to use as a loop cursor. * @root: the rbtree root. * @member: the name of the rb_node within the struct. */ #define rb_for_each_entry(pos, root, member) \ for (pos = rb_entry_safe(rb_first(root), typeof(*pos), member); \ pos; pos = rb_entry_safe(rb_next(&pos->member), typeof(*pos), member)) /** * rb_for_each_entry_safe - Iterate over rbtree of given type safe against removal * @pos: the type * to use as a loop cursor. * @root: the rbtree root. * @member: the name of the rb_node within the struct. */ #define rb_for_each_entry_safe(pos, n, root, member) \ for (pos = rb_entry_safe(rb_first(root), typeof(*pos), member); \ pos && (n = rb_entry_safe(rb_next(&pos->member), typeof(*n), member), 1); \ pos = n) /** * rb_for_each_entry_cached - Iterate over cached rbtree of given type * @pos: the type * to use as a loop cursor. * @root: the rbtree root. * @member: the name of the rb_node within the struct. */ #define rb_for_each_entry_cached(pos, root, member) \ for (pos = rb_entry_safe(rb_first_cached(root), typeof(*pos), member); \ pos; pos = rb_entry_safe(rb_next(&pos->member), typeof(*pos), member)) /** * rb_for_each_entry_safe_cached - Iterate over cached rbtree of given type * @pos: the type * to use as a loop cursor. * @root: the rbtree root. * @member: the name of the rb_node within the struct. */ #define rb_for_each_entry_safe_cached(pos, n, root, member) \ for (pos = rb_entry_safe(rb_first_cached(root), typeof(*pos), member); \ pos && (n = rb_entry_safe(rb_next(&pos->member), typeof(*n), member), 1); \ pos = n) /** * rb_for_each_entry_from - Iterate over rbtree of given type from the given point * @pos: the type * to use as a loop cursor. * @root: the rbtree root. * @member: the name of the rb_node within the struct. */ #define rb_for_each_entry_from(pos, root, member) \ for (rb_node_t *n = &pos->member; \ n && pos = rb_entry(n, typeof(*pos), member); \ n = rb_next(n)) /** * rb_move_cached - Move node to new position in tree * @root: the rbtree root. * @node: the node to move. * @member: the name of the rb_node within the struct. * @compar: the name of the comparison function to use. */ #define rb_move_cached(root, node, member, compar) \ ({ \ rb_node_t *prev_node, *next_node; \ typeof(node) prev, next; \ \ prev_node = rb_prev(&node->member); \ next_node = rb_next(&node->member); \ \ if (prev_node || next_node) { \ prev = rb_entry_safe(prev_node, typeof(*node), member); \ next = rb_entry_safe(next_node, typeof(*node), member); \ \ /* If node is between our predecessor and sucessor, \ * it can stay where it is */ \ if ((prev && compar(prev, node) > 0) || \ (next && compar(next, node) < 0)) { \ /* Can this be optimised? */ \ rb_erase_cached(&node->member, root); \ rb_insert_sort_cached(root, node, member, compar); \ } \ } \ }) #endif /* _LINUX_RBTREE_H */