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diff --git a/include/import/eb32tree.h b/include/import/eb32tree.h
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+/*
+ * 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 */