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Diffstat (limited to 'include/import/eb32tree.h')
| -rw-r--r-- | include/import/eb32tree.h | 482 |
1 files changed, 482 insertions, 0 deletions
diff --git a/include/import/eb32tree.h b/include/import/eb32tree.h new file mode 100644 index 0000000..1c03fc1 --- /dev/null +++ b/include/import/eb32tree.h @@ -0,0 +1,482 @@ +/* + * Elastic Binary Trees - macros and structures for operations on 32bit nodes. + * Version 6.0.6 + * (C) 2002-2011 - Willy Tarreau <w@1wt.eu> + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation, version 2.1 + * exclusively. + * + * This library 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 + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with this library; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + */ + +#ifndef _EB32TREE_H +#define _EB32TREE_H + +#include "ebtree.h" + + +/* Return the structure of type <type> whose member <member> points to <ptr> */ +#define eb32_entry(ptr, type, member) container_of(ptr, type, member) + +/* + * Exported functions and macros. + * Many of them are always inlined because they are extremely small, and + * are generally called at most once or twice in a program. + */ + +/* Return leftmost node in the tree, or NULL if none */ +static inline struct eb32_node *eb32_first(struct eb_root *root) +{ + return eb32_entry(eb_first(root), struct eb32_node, node); +} + +/* Return rightmost node in the tree, or NULL if none */ +static inline struct eb32_node *eb32_last(struct eb_root *root) +{ + return eb32_entry(eb_last(root), struct eb32_node, node); +} + +/* Return next node in the tree, or NULL if none */ +static inline struct eb32_node *eb32_next(struct eb32_node *eb32) +{ + return eb32_entry(eb_next(&eb32->node), struct eb32_node, node); +} + +/* Return previous node in the tree, or NULL if none */ +static inline struct eb32_node *eb32_prev(struct eb32_node *eb32) +{ + return eb32_entry(eb_prev(&eb32->node), struct eb32_node, node); +} + +/* Return next leaf node within a duplicate sub-tree, or NULL if none. */ +static inline struct eb32_node *eb32_next_dup(struct eb32_node *eb32) +{ + return eb32_entry(eb_next_dup(&eb32->node), struct eb32_node, node); +} + +/* Return previous leaf node within a duplicate sub-tree, or NULL if none. */ +static inline struct eb32_node *eb32_prev_dup(struct eb32_node *eb32) +{ + return eb32_entry(eb_prev_dup(&eb32->node), struct eb32_node, node); +} + +/* Return next node in the tree, skipping duplicates, or NULL if none */ +static inline struct eb32_node *eb32_next_unique(struct eb32_node *eb32) +{ + return eb32_entry(eb_next_unique(&eb32->node), struct eb32_node, node); +} + +/* Return previous node in the tree, skipping duplicates, or NULL if none */ +static inline struct eb32_node *eb32_prev_unique(struct eb32_node *eb32) +{ + return eb32_entry(eb_prev_unique(&eb32->node), struct eb32_node, node); +} + +/* Delete node from the tree if it was linked in. Mark the node unused. Note + * that this function relies on a non-inlined generic function: eb_delete. + */ +static inline void eb32_delete(struct eb32_node *eb32) +{ + eb_delete(&eb32->node); +} + +/* + * The following functions are not inlined by default. They are declared + * in eb32tree.c, which simply relies on their inline version. + */ +struct eb32_node *eb32_lookup(struct eb_root *root, u32 x); +struct eb32_node *eb32i_lookup(struct eb_root *root, s32 x); +struct eb32_node *eb32_lookup_le(struct eb_root *root, u32 x); +struct eb32_node *eb32_lookup_ge(struct eb_root *root, u32 x); +struct eb32_node *eb32_insert(struct eb_root *root, struct eb32_node *new); +struct eb32_node *eb32i_insert(struct eb_root *root, struct eb32_node *new); + +/* + * The following functions are less likely to be used directly, because their + * code is larger. The non-inlined version is preferred. + */ + +/* Delete node from the tree if it was linked in. Mark the node unused. */ +static forceinline void __eb32_delete(struct eb32_node *eb32) +{ + __eb_delete(&eb32->node); +} + +/* + * Find the first occurrence of a key in the tree <root>. If none can be + * found, return NULL. + */ +static forceinline struct eb32_node *__eb32_lookup(struct eb_root *root, u32 x) +{ + struct eb32_node *node; + eb_troot_t *troot; + u32 y; + int node_bit; + + troot = root->b[EB_LEFT]; + if (unlikely(troot == NULL)) + return NULL; + + while (1) { + if ((eb_gettag(troot) == EB_LEAF)) { + node = container_of(eb_untag(troot, EB_LEAF), + struct eb32_node, node.branches); + if (node->key == x) + return node; + else + return NULL; + } + node = container_of(eb_untag(troot, EB_NODE), + struct eb32_node, node.branches); + node_bit = node->node.bit; + + y = node->key ^ x; + if (!y) { + /* Either we found the node which holds the key, or + * we have a dup tree. In the later case, we have to + * walk it down left to get the first entry. + */ + if (node_bit < 0) { + troot = node->node.branches.b[EB_LEFT]; + while (eb_gettag(troot) != EB_LEAF) + troot = (eb_untag(troot, EB_NODE))->b[EB_LEFT]; + node = container_of(eb_untag(troot, EB_LEAF), + struct eb32_node, node.branches); + } + return node; + } + + if ((y >> node_bit) >= EB_NODE_BRANCHES) + return NULL; /* no more common bits */ + + troot = node->node.branches.b[(x >> node_bit) & EB_NODE_BRANCH_MASK]; + } +} + +/* + * Find the first occurrence of a signed key in the tree <root>. If none can + * be found, return NULL. + */ +static forceinline struct eb32_node *__eb32i_lookup(struct eb_root *root, s32 x) +{ + struct eb32_node *node; + eb_troot_t *troot; + u32 key = x ^ 0x80000000; + u32 y; + int node_bit; + + troot = root->b[EB_LEFT]; + if (unlikely(troot == NULL)) + return NULL; + + while (1) { + if ((eb_gettag(troot) == EB_LEAF)) { + node = container_of(eb_untag(troot, EB_LEAF), + struct eb32_node, node.branches); + if (node->key == (u32)x) + return node; + else + return NULL; + } + node = container_of(eb_untag(troot, EB_NODE), + struct eb32_node, node.branches); + node_bit = node->node.bit; + + y = node->key ^ x; + if (!y) { + /* Either we found the node which holds the key, or + * we have a dup tree. In the later case, we have to + * walk it down left to get the first entry. + */ + if (node_bit < 0) { + troot = node->node.branches.b[EB_LEFT]; + while (eb_gettag(troot) != EB_LEAF) + troot = (eb_untag(troot, EB_NODE))->b[EB_LEFT]; + node = container_of(eb_untag(troot, EB_LEAF), + struct eb32_node, node.branches); + } + return node; + } + + if ((y >> node_bit) >= EB_NODE_BRANCHES) + return NULL; /* no more common bits */ + + troot = node->node.branches.b[(key >> node_bit) & EB_NODE_BRANCH_MASK]; + } +} + +/* Insert eb32_node <new> into subtree starting at node root <root>. + * Only new->key needs be set with the key. The eb32_node is returned. + * If root->b[EB_RGHT]==1, the tree may only contain unique keys. + */ +static forceinline struct eb32_node * +__eb32_insert(struct eb_root *root, struct eb32_node *new) { + struct eb32_node *old; + unsigned int side; + eb_troot_t *troot, **up_ptr; + u32 newkey; /* caching the key saves approximately one cycle */ + eb_troot_t *root_right; + eb_troot_t *new_left, *new_rght; + eb_troot_t *new_leaf; + int old_node_bit; + + side = EB_LEFT; + troot = root->b[EB_LEFT]; + root_right = root->b[EB_RGHT]; + if (unlikely(troot == NULL)) { + /* Tree is empty, insert the leaf part below the left branch */ + root->b[EB_LEFT] = eb_dotag(&new->node.branches, EB_LEAF); + new->node.leaf_p = eb_dotag(root, EB_LEFT); + new->node.node_p = NULL; /* node part unused */ + return new; + } + + /* The tree descent is fairly easy : + * - first, check if we have reached a leaf node + * - second, check if we have gone too far + * - third, reiterate + * Everywhere, we use <new> for the node node we are inserting, <root> + * for the node we attach it to, and <old> for the node we are + * displacing below <new>. <troot> will always point to the future node + * (tagged with its type). <side> carries the side the node <new> is + * attached to below its parent, which is also where previous node + * was attached. <newkey> carries the key being inserted. + */ + newkey = new->key; + + while (1) { + if (eb_gettag(troot) == EB_LEAF) { + /* insert above a leaf */ + old = container_of(eb_untag(troot, EB_LEAF), + struct eb32_node, node.branches); + new->node.node_p = old->node.leaf_p; + up_ptr = &old->node.leaf_p; + break; + } + + /* OK we're walking down this link */ + old = container_of(eb_untag(troot, EB_NODE), + struct eb32_node, node.branches); + old_node_bit = old->node.bit; + + /* Stop going down when we don't have common bits anymore. We + * also stop in front of a duplicates tree because it means we + * have to insert above. + */ + + if ((old_node_bit < 0) || /* we're above a duplicate tree, stop here */ + (((new->key ^ old->key) >> old_node_bit) >= EB_NODE_BRANCHES)) { + /* The tree did not contain the key, so we insert <new> before the node + * <old>, and set ->bit to designate the lowest bit position in <new> + * which applies to ->branches.b[]. + */ + new->node.node_p = old->node.node_p; + up_ptr = &old->node.node_p; + break; + } + + /* walk down */ + root = &old->node.branches; + side = (newkey >> old_node_bit) & EB_NODE_BRANCH_MASK; + troot = root->b[side]; + } + + new_left = eb_dotag(&new->node.branches, EB_LEFT); + new_rght = eb_dotag(&new->node.branches, EB_RGHT); + new_leaf = eb_dotag(&new->node.branches, EB_LEAF); + + /* We need the common higher bits between new->key and old->key. + * What differences are there between new->key and the node here ? + * NOTE that bit(new) is always < bit(root) because highest + * bit of new->key and old->key are identical here (otherwise they + * would sit on different branches). + */ + + // note that if EB_NODE_BITS > 1, we should check that it's still >= 0 + new->node.bit = flsnz(new->key ^ old->key) - EB_NODE_BITS; + + if (new->key == old->key) { + new->node.bit = -1; /* mark as new dup tree, just in case */ + + if (likely(eb_gettag(root_right))) { + /* we refuse to duplicate this key if the tree is + * tagged as containing only unique keys. + */ + return old; + } + + if (eb_gettag(troot) != EB_LEAF) { + /* there was already a dup tree below */ + struct eb_node *ret; + ret = eb_insert_dup(&old->node, &new->node); + return container_of(ret, struct eb32_node, node); + } + /* otherwise fall through */ + } + + if (new->key >= old->key) { + new->node.branches.b[EB_LEFT] = troot; + new->node.branches.b[EB_RGHT] = new_leaf; + new->node.leaf_p = new_rght; + *up_ptr = new_left; + } + else { + new->node.branches.b[EB_LEFT] = new_leaf; + new->node.branches.b[EB_RGHT] = troot; + new->node.leaf_p = new_left; + *up_ptr = new_rght; + } + + /* Ok, now we are inserting <new> between <root> and <old>. <old>'s + * parent is already set to <new>, and the <root>'s branch is still in + * <side>. Update the root's leaf till we have it. Note that we can also + * find the side by checking the side of new->node.node_p. + */ + + root->b[side] = eb_dotag(&new->node.branches, EB_NODE); + return new; +} + +/* Insert eb32_node <new> into subtree starting at node root <root>, using + * signed keys. Only new->key needs be set with the key. The eb32_node + * is returned. If root->b[EB_RGHT]==1, the tree may only contain unique keys. + */ +static forceinline struct eb32_node * +__eb32i_insert(struct eb_root *root, struct eb32_node *new) { + struct eb32_node *old; + unsigned int side; + eb_troot_t *troot, **up_ptr; + int newkey; /* caching the key saves approximately one cycle */ + eb_troot_t *root_right; + eb_troot_t *new_left, *new_rght; + eb_troot_t *new_leaf; + int old_node_bit; + + side = EB_LEFT; + troot = root->b[EB_LEFT]; + root_right = root->b[EB_RGHT]; + if (unlikely(troot == NULL)) { + /* Tree is empty, insert the leaf part below the left branch */ + root->b[EB_LEFT] = eb_dotag(&new->node.branches, EB_LEAF); + new->node.leaf_p = eb_dotag(root, EB_LEFT); + new->node.node_p = NULL; /* node part unused */ + return new; + } + + /* The tree descent is fairly easy : + * - first, check if we have reached a leaf node + * - second, check if we have gone too far + * - third, reiterate + * Everywhere, we use <new> for the node node we are inserting, <root> + * for the node we attach it to, and <old> for the node we are + * displacing below <new>. <troot> will always point to the future node + * (tagged with its type). <side> carries the side the node <new> is + * attached to below its parent, which is also where previous node + * was attached. <newkey> carries a high bit shift of the key being + * inserted in order to have negative keys stored before positive + * ones. + */ + newkey = new->key + 0x80000000; + + while (1) { + if (eb_gettag(troot) == EB_LEAF) { + old = container_of(eb_untag(troot, EB_LEAF), + struct eb32_node, node.branches); + new->node.node_p = old->node.leaf_p; + up_ptr = &old->node.leaf_p; + break; + } + + /* OK we're walking down this link */ + old = container_of(eb_untag(troot, EB_NODE), + struct eb32_node, node.branches); + old_node_bit = old->node.bit; + + /* Stop going down when we don't have common bits anymore. We + * also stop in front of a duplicates tree because it means we + * have to insert above. + */ + + if ((old_node_bit < 0) || /* we're above a duplicate tree, stop here */ + (((new->key ^ old->key) >> old_node_bit) >= EB_NODE_BRANCHES)) { + /* The tree did not contain the key, so we insert <new> before the node + * <old>, and set ->bit to designate the lowest bit position in <new> + * which applies to ->branches.b[]. + */ + new->node.node_p = old->node.node_p; + up_ptr = &old->node.node_p; + break; + } + + /* walk down */ + root = &old->node.branches; + side = (newkey >> old_node_bit) & EB_NODE_BRANCH_MASK; + troot = root->b[side]; + } + + new_left = eb_dotag(&new->node.branches, EB_LEFT); + new_rght = eb_dotag(&new->node.branches, EB_RGHT); + new_leaf = eb_dotag(&new->node.branches, EB_LEAF); + + /* We need the common higher bits between new->key and old->key. + * What differences are there between new->key and the node here ? + * NOTE that bit(new) is always < bit(root) because highest + * bit of new->key and old->key are identical here (otherwise they + * would sit on different branches). + */ + + // note that if EB_NODE_BITS > 1, we should check that it's still >= 0 + new->node.bit = flsnz(new->key ^ old->key) - EB_NODE_BITS; + + if (new->key == old->key) { + new->node.bit = -1; /* mark as new dup tree, just in case */ + + if (likely(eb_gettag(root_right))) { + /* we refuse to duplicate this key if the tree is + * tagged as containing only unique keys. + */ + return old; + } + + if (eb_gettag(troot) != EB_LEAF) { + /* there was already a dup tree below */ + struct eb_node *ret; + ret = eb_insert_dup(&old->node, &new->node); + return container_of(ret, struct eb32_node, node); + } + /* otherwise fall through */ + } + + if ((s32)new->key >= (s32)old->key) { + new->node.branches.b[EB_LEFT] = troot; + new->node.branches.b[EB_RGHT] = new_leaf; + new->node.leaf_p = new_rght; + *up_ptr = new_left; + } + else { + new->node.branches.b[EB_LEFT] = new_leaf; + new->node.branches.b[EB_RGHT] = troot; + new->node.leaf_p = new_left; + *up_ptr = new_rght; + } + + /* Ok, now we are inserting <new> between <root> and <old>. <old>'s + * parent is already set to <new>, and the <root>'s branch is still in + * <side>. Update the root's leaf till we have it. Note that we can also + * find the side by checking the side of new->node.node_p. + */ + + root->b[side] = eb_dotag(&new->node.branches, EB_NODE); + return new; +} + +#endif /* _EB32_TREE_H */ |