[MINOR] merge ebtree version 3.0
Version 3.0 of ebtree has been merged in but is not used yet.
diff --git a/include/common/eb32tree.h b/include/common/eb32tree.h
new file mode 100644
index 0000000..87c2f98
--- /dev/null
+++ b/include/common/eb32tree.h
@@ -0,0 +1,513 @@
+/*
+ * Elastic Binary Trees - macros and structures for operations on 32bit nodes.
+ * (C) 2002-2007 - Willy Tarreau <w@1wt.eu>
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#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)
+
+#define EB32_ROOT EB_ROOT
+#define EB32_TREE_HEAD EB_TREE_HEAD
+
+/* These types may sometimes already be defined */
+typedef unsigned int u32;
+typedef signed int s32;
+
+/* This structure carries a node, a leaf, and a key. It must start with the
+ * eb_node so that it can be cast into an eb_node. We could also have put some
+ * sort of transparent union here to reduce the indirection level, but the fact
+ * is, the end user is not meant to manipulate internals, so this is pointless.
+ */
+struct eb32_node {
+ struct eb_node node; /* the tree node, must be at the beginning */
+ u32 key;
+};
+
+/*
+ * 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 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.
+ */
+REGPRM2 struct eb32_node *eb32_lookup(struct eb_root *root, u32 x);
+REGPRM2 struct eb32_node *eb32i_lookup(struct eb_root *root, s32 x);
+REGPRM2 struct eb32_node *eb32_insert(struct eb_root *root, struct eb32_node *new);
+REGPRM2 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 inline void __eb32_delete(struct eb32_node *eb32)
+{
+ __eb_delete(&eb32->node);
+}
+
+/*
+ * Find the first occurence of a key in the tree <root>. If none can be
+ * found, return NULL.
+ */
+static inline struct eb32_node *__eb32_lookup(struct eb_root *root, u32 x)
+{
+ struct eb32_node *node;
+ eb_troot_t *troot;
+
+ 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);
+
+ if (x == node->key) {
+ /* 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->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;
+ }
+
+ troot = node->node.branches.b[(x >> node->node.bit) & EB_NODE_BRANCH_MASK];
+ }
+}
+
+/*
+ * Find the first occurence of a signed key in the tree <root>. If none can
+ * be found, return NULL.
+ */
+static inline struct eb32_node *__eb32i_lookup(struct eb_root *root, s32 x)
+{
+ struct eb32_node *node;
+ eb_troot_t *troot;
+ u32 key = x ^ 0x80000000;
+
+ 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);
+
+ if (x == node->key) {
+ /* 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->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;
+ }
+
+ troot = node->node.branches.b[(key >> node->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.
+ */
+static inline struct eb32_node *
+__eb32_insert(struct eb_root *root, struct eb32_node *new) {
+ struct eb32_node *old;
+ unsigned int side;
+ eb_troot_t *troot;
+ u32 newkey; /* caching the key saves approximately one cycle */
+
+ side = EB_LEFT;
+ troot = root->b[EB_LEFT];
+ 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 (unlikely(eb_gettag(troot) == EB_LEAF)) {
+ eb_troot_t *new_left, *new_rght;
+ eb_troot_t *new_leaf, *old_leaf;
+
+ old = container_of(eb_untag(troot, EB_LEAF),
+ struct eb32_node, node.branches);
+
+ 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);
+ old_leaf = eb_dotag(&old->node.branches, EB_LEAF);
+
+ new->node.node_p = old->node.leaf_p;
+
+ /* Right here, we have 3 possibilities :
+ - the tree does not contain the key, and we have
+ new->key < old->key. We insert new above old, on
+ the left ;
+
+ - the tree does not contain the key, and we have
+ new->key > old->key. We insert new above old, on
+ the right ;
+
+ - the tree does contain the key, which implies it
+ is alone. We add the new key next to it as a
+ first duplicate.
+
+ The last two cases can easily be partially merged.
+ */
+
+ if (new->key < old->key) {
+ new->node.leaf_p = new_left;
+ old->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = new_leaf;
+ new->node.branches.b[EB_RGHT] = old_leaf;
+ } else {
+ /* new->key >= old->key, new goes the right */
+ old->node.leaf_p = new_left;
+ new->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = old_leaf;
+ new->node.branches.b[EB_RGHT] = new_leaf;
+
+ if (new->key == old->key) {
+ new->node.bit = -1;
+ root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
+ return new;
+ }
+ }
+ break;
+ }
+
+ /* OK we're walking down this link */
+ old = container_of(eb_untag(troot, EB_NODE),
+ struct eb32_node, node.branches);
+
+ /* 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[].
+ */
+ eb_troot_t *new_left, *new_rght;
+ eb_troot_t *new_leaf, *old_node;
+
+ 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);
+ old_node = eb_dotag(&old->node.branches, EB_NODE);
+
+ new->node.node_p = old->node.node_p;
+
+ if (new->key < old->key) {
+ new->node.leaf_p = new_left;
+ old->node.node_p = new_rght;
+ new->node.branches.b[EB_LEFT] = new_leaf;
+ new->node.branches.b[EB_RGHT] = old_node;
+ }
+ else if (new->key > old->key) {
+ old->node.node_p = new_left;
+ new->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = old_node;
+ new->node.branches.b[EB_RGHT] = new_leaf;
+ }
+ else {
+ struct eb_node *ret;
+ ret = eb_insert_dup(&old->node, &new->node);
+ return container_of(ret, struct eb32_node, node);
+ }
+ break;
+ }
+
+ /* walk down */
+ root = &old->node.branches;
+ side = (newkey >> old->node.bit) & EB_NODE_BRANCH_MASK;
+ troot = root->b[side];
+ }
+
+ /* 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.
+ */
+
+ /* 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;
+ 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
+ */
+static inline struct eb32_node *
+__eb32i_insert(struct eb_root *root, struct eb32_node *new) {
+ struct eb32_node *old;
+ unsigned int side;
+ eb_troot_t *troot;
+ int newkey; /* caching the key saves approximately one cycle */
+
+ side = EB_LEFT;
+ troot = root->b[EB_LEFT];
+ 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 (unlikely(eb_gettag(troot) == EB_LEAF)) {
+ eb_troot_t *new_left, *new_rght;
+ eb_troot_t *new_leaf, *old_leaf;
+
+ old = container_of(eb_untag(troot, EB_LEAF),
+ struct eb32_node, node.branches);
+
+ 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);
+ old_leaf = eb_dotag(&old->node.branches, EB_LEAF);
+
+ new->node.node_p = old->node.leaf_p;
+
+ /* Right here, we have 3 possibilities :
+ - the tree does not contain the key, and we have
+ new->key < old->key. We insert new above old, on
+ the left ;
+
+ - the tree does not contain the key, and we have
+ new->key > old->key. We insert new above old, on
+ the right ;
+
+ - the tree does contain the key, which implies it
+ is alone. We add the new key next to it as a
+ first duplicate.
+
+ The last two cases can easily be partially merged.
+ */
+
+ if ((s32)new->key < (s32)old->key) {
+ new->node.leaf_p = new_left;
+ old->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = new_leaf;
+ new->node.branches.b[EB_RGHT] = old_leaf;
+ } else {
+ /* new->key >= old->key, new goes the right */
+ old->node.leaf_p = new_left;
+ new->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = old_leaf;
+ new->node.branches.b[EB_RGHT] = new_leaf;
+
+ if (new->key == old->key) {
+ new->node.bit = -1;
+ root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
+ return new;
+ }
+ }
+ break;
+ }
+
+ /* OK we're walking down this link */
+ old = container_of(eb_untag(troot, EB_NODE),
+ struct eb32_node, node.branches);
+
+ /* 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[].
+ */
+ eb_troot_t *new_left, *new_rght;
+ eb_troot_t *new_leaf, *old_node;
+
+ 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);
+ old_node = eb_dotag(&old->node.branches, EB_NODE);
+
+ new->node.node_p = old->node.node_p;
+
+ if ((s32)new->key < (s32)old->key) {
+ new->node.leaf_p = new_left;
+ old->node.node_p = new_rght;
+ new->node.branches.b[EB_LEFT] = new_leaf;
+ new->node.branches.b[EB_RGHT] = old_node;
+ }
+ else if ((s32)new->key > (s32)old->key) {
+ old->node.node_p = new_left;
+ new->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = old_node;
+ new->node.branches.b[EB_RGHT] = new_leaf;
+ }
+ else {
+ struct eb_node *ret;
+ ret = eb_insert_dup(&old->node, &new->node);
+ return container_of(ret, struct eb32_node, node);
+ }
+ break;
+ }
+
+ /* walk down */
+ root = &old->node.branches;
+ side = (newkey >> old->node.bit) & EB_NODE_BRANCH_MASK;
+ troot = root->b[side];
+ }
+
+ /* 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.
+ */
+
+ /* 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;
+ root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
+
+ return new;
+}
diff --git a/include/common/eb64tree.h b/include/common/eb64tree.h
new file mode 100644
index 0000000..242e2b1
--- /dev/null
+++ b/include/common/eb64tree.h
@@ -0,0 +1,534 @@
+/*
+ * Elastic Binary Trees - macros and structures for operations on 64bit nodes.
+ * (C) 2002-2007 - Willy Tarreau <w@1wt.eu>
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "ebtree.h"
+
+
+/* Return the structure of type <type> whose member <member> points to <ptr> */
+#define eb64_entry(ptr, type, member) container_of(ptr, type, member)
+
+#define EB64_ROOT EB_ROOT
+#define EB64_TREE_HEAD EB_TREE_HEAD
+
+/* These types may sometimes already be defined */
+typedef unsigned long long u64;
+typedef signed long long s64;
+
+/* This structure carries a node, a leaf, and a key. It must start with the
+ * eb_node so that it can be cast into an eb_node. We could also have put some
+ * sort of transparent union here to reduce the indirection level, but the fact
+ * is, the end user is not meant to manipulate internals, so this is pointless.
+ */
+struct eb64_node {
+ struct eb_node node; /* the tree node, must be at the beginning */
+ u64 key;
+};
+
+/*
+ * 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 eb64_node *eb64_first(struct eb_root *root)
+{
+ return eb64_entry(eb_first(root), struct eb64_node, node);
+}
+
+/* Return rightmost node in the tree, or NULL if none */
+static inline struct eb64_node *eb64_last(struct eb_root *root)
+{
+ return eb64_entry(eb_last(root), struct eb64_node, node);
+}
+
+/* Return next node in the tree, or NULL if none */
+static inline struct eb64_node *eb64_next(struct eb64_node *eb64)
+{
+ return eb64_entry(eb_next(&eb64->node), struct eb64_node, node);
+}
+
+/* Return previous node in the tree, or NULL if none */
+static inline struct eb64_node *eb64_prev(struct eb64_node *eb64)
+{
+ return eb64_entry(eb_prev(&eb64->node), struct eb64_node, node);
+}
+
+/* Return next node in the tree, skipping duplicates, or NULL if none */
+static inline struct eb64_node *eb64_next_unique(struct eb64_node *eb64)
+{
+ return eb64_entry(eb_next_unique(&eb64->node), struct eb64_node, node);
+}
+
+/* Return previous node in the tree, skipping duplicates, or NULL if none */
+static inline struct eb64_node *eb64_prev_unique(struct eb64_node *eb64)
+{
+ return eb64_entry(eb_prev_unique(&eb64->node), struct eb64_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 eb64_delete(struct eb64_node *eb64)
+{
+ eb_delete(&eb64->node);
+}
+
+/*
+ * The following functions are not inlined by default. They are declared
+ * in eb64tree.c, which simply relies on their inline version.
+ */
+REGPRM2 struct eb64_node *eb64_lookup(struct eb_root *root, u64 x);
+REGPRM2 struct eb64_node *eb64i_lookup(struct eb_root *root, s64 x);
+REGPRM2 struct eb64_node *eb64_insert(struct eb_root *root, struct eb64_node *new);
+REGPRM2 struct eb64_node *eb64i_insert(struct eb_root *root, struct eb64_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 inline void __eb64_delete(struct eb64_node *eb64)
+{
+ __eb_delete(&eb64->node);
+}
+
+/*
+ * Find the first occurence of a key in the tree <root>. If none can be
+ * found, return NULL.
+ */
+static inline struct eb64_node *__eb64_lookup(struct eb_root *root, u64 x)
+{
+ struct eb64_node *node;
+ eb_troot_t *troot;
+
+ 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 eb64_node, node.branches);
+ if (node->key == x)
+ return node;
+ else
+ return NULL;
+ }
+ node = container_of(eb_untag(troot, EB_NODE),
+ struct eb64_node, node.branches);
+
+ if (x == node->key) {
+ /* 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->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 eb64_node, node.branches);
+ }
+ return node;
+ }
+
+ troot = node->node.branches.b[(x >> node->node.bit) & EB_NODE_BRANCH_MASK];
+ }
+}
+
+/*
+ * Find the first occurence of a signed key in the tree <root>. If none can
+ * be found, return NULL.
+ */
+static inline struct eb64_node *__eb64i_lookup(struct eb_root *root, s64 x)
+{
+ struct eb64_node *node;
+ eb_troot_t *troot;
+ u64 key = x ^ (1ULL << 63);
+
+ 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 eb64_node, node.branches);
+ if (node->key == x)
+ return node;
+ else
+ return NULL;
+ }
+ node = container_of(eb_untag(troot, EB_NODE),
+ struct eb64_node, node.branches);
+
+ if (x == node->key) {
+ /* 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->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 eb64_node, node.branches);
+ }
+ return node;
+ }
+
+ troot = node->node.branches.b[(key >> node->node.bit) & EB_NODE_BRANCH_MASK];
+ }
+}
+
+/* Insert eb64_node <new> into subtree starting at node root <root>.
+ * Only new->key needs be set with the key. The eb64_node is returned.
+ */
+static inline struct eb64_node *
+__eb64_insert(struct eb_root *root, struct eb64_node *new) {
+ struct eb64_node *old;
+ unsigned int side;
+ eb_troot_t *troot;
+ u64 newkey; /* caching the key saves approximately one cycle */
+
+ side = EB_LEFT;
+ troot = root->b[EB_LEFT];
+ 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 (unlikely(eb_gettag(troot) == EB_LEAF)) {
+ eb_troot_t *new_left, *new_rght;
+ eb_troot_t *new_leaf, *old_leaf;
+
+ old = container_of(eb_untag(troot, EB_LEAF),
+ struct eb64_node, node.branches);
+
+ 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);
+ old_leaf = eb_dotag(&old->node.branches, EB_LEAF);
+
+ new->node.node_p = old->node.leaf_p;
+
+ /* Right here, we have 3 possibilities :
+ - the tree does not contain the key, and we have
+ new->key < old->key. We insert new above old, on
+ the left ;
+
+ - the tree does not contain the key, and we have
+ new->key > old->key. We insert new above old, on
+ the right ;
+
+ - the tree does contain the key, which implies it
+ is alone. We add the new key next to it as a
+ first duplicate.
+
+ The last two cases can easily be partially merged.
+ */
+
+ if (new->key < old->key) {
+ new->node.leaf_p = new_left;
+ old->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = new_leaf;
+ new->node.branches.b[EB_RGHT] = old_leaf;
+ } else {
+ /* new->key >= old->key, new goes the right */
+ old->node.leaf_p = new_left;
+ new->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = old_leaf;
+ new->node.branches.b[EB_RGHT] = new_leaf;
+
+ if (new->key == old->key) {
+ new->node.bit = -1;
+ root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
+ return new;
+ }
+ }
+ break;
+ }
+
+ /* OK we're walking down this link */
+ old = container_of(eb_untag(troot, EB_NODE),
+ struct eb64_node, node.branches);
+
+ /* 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[].
+ */
+ eb_troot_t *new_left, *new_rght;
+ eb_troot_t *new_leaf, *old_node;
+
+ 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);
+ old_node = eb_dotag(&old->node.branches, EB_NODE);
+
+ new->node.node_p = old->node.node_p;
+
+ if (new->key < old->key) {
+ new->node.leaf_p = new_left;
+ old->node.node_p = new_rght;
+ new->node.branches.b[EB_LEFT] = new_leaf;
+ new->node.branches.b[EB_RGHT] = old_node;
+ }
+ else if (new->key > old->key) {
+ old->node.node_p = new_left;
+ new->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = old_node;
+ new->node.branches.b[EB_RGHT] = new_leaf;
+ }
+ else {
+ struct eb_node *ret;
+ ret = eb_insert_dup(&old->node, &new->node);
+ return container_of(ret, struct eb64_node, node);
+ }
+ break;
+ }
+
+ /* walk down */
+ root = &old->node.branches;
+#if BITS_PER_LONG >= 64
+ side = (newkey >> old->node.bit) & EB_NODE_BRANCH_MASK;
+#else
+ side = newkey;
+ side >>= old->node.bit;
+ if (old->node.bit >= 32) {
+ side = newkey >> 32;
+ side >>= old->node.bit & 0x1F;
+ }
+ side &= EB_NODE_BRANCH_MASK;
+#endif
+ troot = root->b[side];
+ }
+
+ /* 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.
+ */
+
+ /* 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 = fls64(new->key ^ old->key) - EB_NODE_BITS;
+ root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
+
+ return new;
+}
+
+/* Insert eb64_node <new> into subtree starting at node root <root>, using
+ * signed keys. Only new->key needs be set with the key. The eb64_node
+ * is returned.
+ */
+static inline struct eb64_node *
+__eb64i_insert(struct eb_root *root, struct eb64_node *new) {
+ struct eb64_node *old;
+ unsigned int side;
+ eb_troot_t *troot;
+ u64 newkey; /* caching the key saves approximately one cycle */
+
+ side = EB_LEFT;
+ troot = root->b[EB_LEFT];
+ 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 ^ (1ULL << 63);
+
+ while (1) {
+ if (unlikely(eb_gettag(troot) == EB_LEAF)) {
+ eb_troot_t *new_left, *new_rght;
+ eb_troot_t *new_leaf, *old_leaf;
+
+ old = container_of(eb_untag(troot, EB_LEAF),
+ struct eb64_node, node.branches);
+
+ 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);
+ old_leaf = eb_dotag(&old->node.branches, EB_LEAF);
+
+ new->node.node_p = old->node.leaf_p;
+
+ /* Right here, we have 3 possibilities :
+ - the tree does not contain the key, and we have
+ new->key < old->key. We insert new above old, on
+ the left ;
+
+ - the tree does not contain the key, and we have
+ new->key > old->key. We insert new above old, on
+ the right ;
+
+ - the tree does contain the key, which implies it
+ is alone. We add the new key next to it as a
+ first duplicate.
+
+ The last two cases can easily be partially merged.
+ */
+
+ if ((s64)new->key < (s64)old->key) {
+ new->node.leaf_p = new_left;
+ old->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = new_leaf;
+ new->node.branches.b[EB_RGHT] = old_leaf;
+ } else {
+ /* new->key >= old->key, new goes the right */
+ old->node.leaf_p = new_left;
+ new->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = old_leaf;
+ new->node.branches.b[EB_RGHT] = new_leaf;
+
+ if (new->key == old->key) {
+ new->node.bit = -1;
+ root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
+ return new;
+ }
+ }
+ break;
+ }
+
+ /* OK we're walking down this link */
+ old = container_of(eb_untag(troot, EB_NODE),
+ struct eb64_node, node.branches);
+
+ /* 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[].
+ */
+ eb_troot_t *new_left, *new_rght;
+ eb_troot_t *new_leaf, *old_node;
+
+ 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);
+ old_node = eb_dotag(&old->node.branches, EB_NODE);
+
+ new->node.node_p = old->node.node_p;
+
+ if ((s64)new->key < (s64)old->key) {
+ new->node.leaf_p = new_left;
+ old->node.node_p = new_rght;
+ new->node.branches.b[EB_LEFT] = new_leaf;
+ new->node.branches.b[EB_RGHT] = old_node;
+ }
+ else if ((s64)new->key > (s64)old->key) {
+ old->node.node_p = new_left;
+ new->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = old_node;
+ new->node.branches.b[EB_RGHT] = new_leaf;
+ }
+ else {
+ struct eb_node *ret;
+ ret = eb_insert_dup(&old->node, &new->node);
+ return container_of(ret, struct eb64_node, node);
+ }
+ break;
+ }
+
+ /* walk down */
+ root = &old->node.branches;
+#if BITS_PER_LONG >= 64
+ side = (newkey >> old->node.bit) & EB_NODE_BRANCH_MASK;
+#else
+ side = newkey;
+ side >>= old->node.bit;
+ if (old->node.bit >= 32) {
+ side = newkey >> 32;
+ side >>= old->node.bit & 0x1F;
+ }
+ side &= EB_NODE_BRANCH_MASK;
+#endif
+ troot = root->b[side];
+ }
+
+ /* 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.
+ */
+
+ /* 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 = fls64(new->key ^ old->key) - EB_NODE_BITS;
+ root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
+
+ return new;
+}
+
diff --git a/include/common/ebpttree.h b/include/common/ebpttree.h
new file mode 100644
index 0000000..4908f81
--- /dev/null
+++ b/include/common/ebpttree.h
@@ -0,0 +1,317 @@
+/*
+ * Elastic Binary Trees - macros and structures for operations on pointer nodes.
+ * (C) 2002-2007 - Willy Tarreau <w@1wt.eu>
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "ebtree.h"
+
+
+/* Return the structure of type <type> whose member <member> points to <ptr> */
+#define ebpt_entry(ptr, type, member) container_of(ptr, type, member)
+
+#define EBPT_ROOT EB_ROOT
+#define EBPT_TREE_HEAD EB_TREE_HEAD
+
+/* on *almost* all platforms, a pointer can be cast into a size_t which is unsigned */
+#ifndef PTR_INT_TYPE
+#define PTR_INT_TYPE size_t
+#endif
+
+typedef PTR_INT_TYPE ptr_t;
+
+/* This structure carries a node, a leaf, and a key. It must start with the
+ * eb_node so that it can be cast into an eb_node. We could also have put some
+ * sort of transparent union here to reduce the indirection level, but the fact
+ * is, the end user is not meant to manipulate internals, so this is pointless.
+ */
+struct ebpt_node {
+ struct eb_node node; /* the tree node, must be at the beginning */
+ void *key;
+};
+
+/*
+ * 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 ebpt_node *ebpt_first(struct eb_root *root)
+{
+ return ebpt_entry(eb_first(root), struct ebpt_node, node);
+}
+
+/* Return rightmost node in the tree, or NULL if none */
+static inline struct ebpt_node *ebpt_last(struct eb_root *root)
+{
+ return ebpt_entry(eb_last(root), struct ebpt_node, node);
+}
+
+/* Return next node in the tree, or NULL if none */
+static inline struct ebpt_node *ebpt_next(struct ebpt_node *ebpt)
+{
+ return ebpt_entry(eb_next(&ebpt->node), struct ebpt_node, node);
+}
+
+/* Return previous node in the tree, or NULL if none */
+static inline struct ebpt_node *ebpt_prev(struct ebpt_node *ebpt)
+{
+ return ebpt_entry(eb_prev(&ebpt->node), struct ebpt_node, node);
+}
+
+/* Return next node in the tree, skipping duplicates, or NULL if none */
+static inline struct ebpt_node *ebpt_next_unique(struct ebpt_node *ebpt)
+{
+ return ebpt_entry(eb_next_unique(&ebpt->node), struct ebpt_node, node);
+}
+
+/* Return previous node in the tree, skipping duplicates, or NULL if none */
+static inline struct ebpt_node *ebpt_prev_unique(struct ebpt_node *ebpt)
+{
+ return ebpt_entry(eb_prev_unique(&ebpt->node), struct ebpt_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 ebpt_delete(struct ebpt_node *ebpt)
+{
+ eb_delete(&ebpt->node);
+}
+
+/*
+ * The following functions are not inlined by default. They are declared
+ * in ebpttree.c, which simply relies on their inline version.
+ */
+REGPRM2 struct ebpt_node *ebpt_lookup(struct eb_root *root, void *x);
+REGPRM2 struct ebpt_node *ebpt_insert(struct eb_root *root, struct ebpt_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 inline void __ebpt_delete(struct ebpt_node *ebpt)
+{
+ __eb_delete(&ebpt->node);
+}
+
+/*
+ * Find the first occurence of a key in the tree <root>. If none can be
+ * found, return NULL.
+ */
+static inline struct ebpt_node *__ebpt_lookup(struct eb_root *root, void *x)
+{
+ struct ebpt_node *node;
+ eb_troot_t *troot;
+
+ 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 ebpt_node, node.branches);
+ if (node->key == x)
+ return node;
+ else
+ return NULL;
+ }
+ node = container_of(eb_untag(troot, EB_NODE),
+ struct ebpt_node, node.branches);
+
+ if (x == node->key) {
+ /* 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->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 ebpt_node, node.branches);
+ }
+ return node;
+ }
+
+ troot = node->node.branches.b[((ptr_t)x >> node->node.bit) & EB_NODE_BRANCH_MASK];
+ }
+}
+
+/* Insert ebpt_node <new> into subtree starting at node root <root>.
+ * Only new->key needs be set with the key. The ebpt_node is returned.
+ */
+static inline struct ebpt_node *
+__ebpt_insert(struct eb_root *root, struct ebpt_node *new) {
+ struct ebpt_node *old;
+ unsigned int side;
+ eb_troot_t *troot;
+ void *newkey; /* caching the key saves approximately one cycle */
+
+ side = EB_LEFT;
+ troot = root->b[EB_LEFT];
+ 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 (unlikely(eb_gettag(troot) == EB_LEAF)) {
+ eb_troot_t *new_left, *new_rght;
+ eb_troot_t *new_leaf, *old_leaf;
+
+ old = container_of(eb_untag(troot, EB_LEAF),
+ struct ebpt_node, node.branches);
+
+ 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);
+ old_leaf = eb_dotag(&old->node.branches, EB_LEAF);
+
+ new->node.node_p = old->node.leaf_p;
+
+ /* Right here, we have 3 possibilities :
+ - the tree does not contain the key, and we have
+ new->key < old->key. We insert new above old, on
+ the left ;
+
+ - the tree does not contain the key, and we have
+ new->key > old->key. We insert new above old, on
+ the right ;
+
+ - the tree does contain the key, which implies it
+ is alone. We add the new key next to it as a
+ first duplicate.
+
+ The last two cases can easily be partially merged.
+ */
+
+ if (new->key < old->key) {
+ new->node.leaf_p = new_left;
+ old->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = new_leaf;
+ new->node.branches.b[EB_RGHT] = old_leaf;
+ } else {
+ /* new->key >= old->key, new goes the right */
+ old->node.leaf_p = new_left;
+ new->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = old_leaf;
+ new->node.branches.b[EB_RGHT] = new_leaf;
+
+ if (new->key == old->key) {
+ new->node.bit = -1;
+ root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
+ return new;
+ }
+ }
+ break;
+ }
+
+ /* OK we're walking down this link */
+ old = container_of(eb_untag(troot, EB_NODE),
+ struct ebpt_node, node.branches);
+
+ /* 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 */
+ ((((ptr_t)new->key ^ (ptr_t)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[].
+ */
+ eb_troot_t *new_left, *new_rght;
+ eb_troot_t *new_leaf, *old_node;
+
+ 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);
+ old_node = eb_dotag(&old->node.branches, EB_NODE);
+
+ new->node.node_p = old->node.node_p;
+
+ if (new->key < old->key) {
+ new->node.leaf_p = new_left;
+ old->node.node_p = new_rght;
+ new->node.branches.b[EB_LEFT] = new_leaf;
+ new->node.branches.b[EB_RGHT] = old_node;
+ }
+ else if (new->key > old->key) {
+ old->node.node_p = new_left;
+ new->node.leaf_p = new_rght;
+ new->node.branches.b[EB_LEFT] = old_node;
+ new->node.branches.b[EB_RGHT] = new_leaf;
+ }
+ else {
+ struct eb_node *ret;
+ ret = eb_insert_dup(&old->node, &new->node);
+ return container_of(ret, struct ebpt_node, node);
+ }
+ break;
+ }
+
+ /* walk down */
+ root = &old->node.branches;
+ side = ((ptr_t)newkey >> old->node.bit) & EB_NODE_BRANCH_MASK;
+ troot = root->b[side];
+ }
+
+ /* 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.
+ */
+
+ /* 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
+
+ /* let the compiler choose the best branch based on the pointer size */
+ if (sizeof(ptr_t) == 4)
+ new->node.bit = flsnz((ptr_t)new->key ^ (ptr_t)old->key) - EB_NODE_BITS;
+ else
+ new->node.bit = fls64((ptr_t)new->key ^ (ptr_t)old->key) - EB_NODE_BITS;
+ root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
+
+ return new;
+}
+
diff --git a/include/common/ebtree.h b/include/common/ebtree.h
new file mode 100644
index 0000000..7a595b9
--- /dev/null
+++ b/include/common/ebtree.h
@@ -0,0 +1,725 @@
+/*
+ * Elastic Binary Trees - generic macros and structures.
+ * (C) 2002-2007 - Willy Tarreau <w@1wt.eu>
+ *
+ * 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ *
+ * Short history :
+ *
+ * 2007/09/28: full support for the duplicates tree => v3
+ * 2007/07/08: merge back cleanups from kernel version.
+ * 2007/07/01: merge into Linux Kernel (try 1).
+ * 2007/05/27: version 2: compact everything into one single struct
+ * 2007/05/18: adapted the structure to support embedded nodes
+ * 2007/05/13: adapted to mempools v2.
+ */
+
+
+
+/*
+ General idea:
+ -------------
+ In a radix binary tree, we may have up to 2N-1 nodes for N keys if all of
+ them are leaves. If we find a way to differentiate intermediate nodes (later
+ called "nodes") and final nodes (later called "leaves"), and we associate
+ them by two, it is possible to build sort of a self-contained radix tree with
+ intermediate nodes always present. It will not be as cheap as the ultree for
+ optimal cases as shown below, but the optimal case almost never happens :
+
+ Eg, to store 8, 10, 12, 13, 14 :
+
+ ultree this theorical tree
+
+ 8 8
+ / \ / \
+ 10 12 10 12
+ / \ / \
+ 13 14 12 14
+ / \
+ 12 13
+
+ Note that on real-world tests (with a scheduler), is was verified that the
+ case with data on an intermediate node never happens. This is because the
+ data spectrum is too large for such coincidences to happen. It would require
+ for instance that a task has its expiration time at an exact second, with
+ other tasks sharing that second. This is too rare to try to optimize for it.
+
+ What is interesting is that the node will only be added above the leaf when
+ necessary, which implies that it will always remain somewhere above it. So
+ both the leaf and the node can share the exact value of the leaf, because
+ when going down the node, the bit mask will be applied to comparisons. So we
+ are tempted to have one single key shared between the node and the leaf.
+
+ The bit only serves the nodes, and the dups only serve the leaves. So we can
+ put a lot of information in common. This results in one single entity with
+ two branch pointers and two parent pointers, one for the node part, and one
+ for the leaf part :
+
+ node's leaf's
+ parent parent
+ | |
+ [node] [leaf]
+ / \
+ left right
+ branch branch
+
+ The node may very well refer to its leaf counterpart in one of its branches,
+ indicating that its own leaf is just below it :
+
+ node's
+ parent
+ |
+ [node]
+ / \
+ left [leaf]
+ branch
+
+ Adding keys in such a tree simply consists in inserting nodes between
+ other nodes and/or leaves :
+
+ [root]
+ |
+ [node2]
+ / \
+ [leaf1] [node3]
+ / \
+ [leaf2] [leaf3]
+
+ On this diagram, we notice that [node2] and [leaf2] have been pulled away
+ from each other due to the insertion of [node3], just as if there would be
+ an elastic between both parts. This elastic-like behaviour gave its name to
+ the tree : "Elastic Binary Tree", or "EBtree". The entity which associates a
+ node part and a leaf part will be called an "EB node".
+
+ We also notice on the diagram that there is a root entity required to attach
+ the tree. It only contains two branches and there is nothing above it. This
+ is an "EB root". Some will note that [leaf1] has no [node1]. One property of
+ the EBtree is that all nodes have their branches filled, and that if a node
+ has only one branch, it does not need to exist. Here, [leaf1] was added
+ below [root] and did not need any node.
+
+ An EB node contains :
+ - a pointer to the node's parent (node_p)
+ - a pointer to the leaf's parent (leaf_p)
+ - two branches pointing to lower nodes or leaves (branches)
+ - a bit position (bit)
+ - an optional key.
+
+ The key here is optional because it's used only during insertion, in order
+ to classify the nodes. Nothing else in the tree structure requires knowledge
+ of the key. This makes it possible to write type-agnostic primitives for
+ everything, and type-specific insertion primitives. This has led to consider
+ two types of EB nodes. The type-agnostic ones will serve as a header for the
+ other ones, and will simply be called "struct eb_node". The other ones will
+ have their type indicated in the structure name. Eg: "struct eb32_node" for
+ nodes carrying 32 bit keys.
+
+ We will also node that the two branches in a node serve exactly the same
+ purpose as an EB root. For this reason, a "struct eb_root" will be used as
+ well inside the struct eb_node. In order to ease pointer manipulation and
+ ROOT detection when walking upwards, all the pointers inside an eb_node will
+ point to the eb_root part of the referenced EB nodes, relying on the same
+ principle as the linked lists in Linux.
+
+ Another important point to note, is that when walking inside a tree, it is
+ very convenient to know where a node is attached in its parent, and what
+ type of branch it has below it (leaf or node). In order to simplify the
+ operations and to speed up the processing, it was decided in this specific
+ implementation to use the lowest bit from the pointer to designate the side
+ of the upper pointers (left/right) and the type of a branch (leaf/node).
+ This practise is not mandatory by design, but an implementation-specific
+ optimisation permitted on all platforms on which data must be aligned. All
+ known 32 bit platforms align their integers and pointers to 32 bits, leaving
+ the two lower bits unused. So, we say that the pointers are "tagged". And
+ since they designate pointers to root parts, we simply call them
+ "tagged root pointers", or "eb_troot" in the code.
+
+ Duplicate keys are stored in a special manner. When inserting a key, if
+ the same one is found, then an incremental binary tree is built at this
+ place from these keys. This ensures that no special case has to be written
+ to handle duplicates when walking through the tree or when deleting entries.
+ It also guarantees that duplicates will be walked in the exact same order
+ they were inserted. This is very important when trying to achieve fair
+ processing distribution for instance.
+
+ Algorithmic complexity can be derived from 3 variables :
+ - the number of possible different keys in the tree : P
+ - the number of entries in the tree : N
+ - the number of duplicates for one key : D
+
+ Note that this tree is deliberately NOT balanced. For this reason, the worst
+ case may happen with a small tree (eg: 32 distinct keys of one bit). BUT,
+ the operations required to manage such data are so much cheap that they make
+ it worth using it even under such conditions. For instance, a balanced tree
+ may require only 6 levels to store those 32 keys when this tree will
+ require 32. But if per-level operations are 5 times cheaper, it wins.
+
+ Minimal, Maximal and Average times are specified in number of operations.
+ Minimal is given for best condition, Maximal for worst condition, and the
+ average is reported for a tree containing random keys. An operation
+ generally consists in jumping from one node to the other.
+
+ Complexity :
+ - lookup : min=1, max=log(P), avg=log(N)
+ - insertion from root : min=1, max=log(P), avg=log(N)
+ - insertion of dups : min=1, max=log(D), avg=log(D)/2 after lookup
+ - deletion : min=1, max=1, avg=1
+ - prev/next : min=1, max=log(P), avg=2 :
+ N/2 nodes need 1 hop => 1*N/2
+ N/4 nodes need 2 hops => 2*N/4
+ N/8 nodes need 3 hops => 3*N/8
+ ...
+ N/x nodes need log(x) hops => log2(x)*N/x
+ Total cost for all N nodes : sum[i=1..N](log2(i)*N/i) = N*sum[i=1..N](log2(i)/i)
+ Average cost across N nodes = total / N = sum[i=1..N](log2(i)/i) = 2
+
+ This design is currently limited to only two branches per node. Most of the
+ tree descent algorithm would be compatible with more branches (eg: 4, to cut
+ the height in half), but this would probably require more complex operations
+ and the deletion algorithm would be problematic.
+
+ Useful properties :
+ - a node is always added above the leaf it is tied to, and never can get
+ below nor in another branch. This implies that leaves directly attached
+ to the root do not use their node part, which is indicated by a NULL
+ value in node_p. This also enhances the cache efficiency when walking
+ down the tree, because when the leaf is reached, its node part will
+ already have been visited (unless it's the first leaf in the tree).
+
+ - pointers to lower nodes or leaves are stored in "branch" pointers. Only
+ the root node may have a NULL in either branch, it is not possible for
+ other branches. Since the nodes are attached to the left branch of the
+ root, it is not possible to see a NULL left branch when walking up a
+ tree. Thus, an empty tree is immediately identified by a NULL left
+ branch at the root. Conversely, the one and only way to identify the
+ root node is to check that it right branch is NULL.
+
+ - a node connected to its own leaf will have branch[0|1] pointing to
+ itself, and leaf_p pointing to itself.
+
+ - a node can never have node_p pointing to itself.
+
+ - a node is linked in a tree if and only if it has a non-null leaf_p.
+
+ - a node can never have both branches equal, except for the root which can
+ have them both NULL.
+
+ - deletion only applies to leaves. When a leaf is deleted, its parent must
+ be released too (unless it's the root), and its sibling must attach to
+ the grand-parent, replacing the parent. Also, when a leaf is deleted,
+ the node tied to this leaf will be removed and must be released too. If
+ this node is different from the leaf's parent, the freshly released
+ leaf's parent will be used to replace the node which must go. A released
+ node will never be used anymore, so there's no point in tracking it.
+
+ - the bit index in a node indicates the bit position in the key which is
+ represented by the branches. That means that a node with (bit == 0) is
+ just above two leaves. Negative bit values are used to build a duplicate
+ tree. The first node above two identical leaves gets (bit == -1). This
+ value logarithmically decreases as the duplicate tree grows. During
+ duplicate insertion, a node is inserted above the highest bit value (the
+ lowest absolute value) in the tree during the right-sided walk. If bit
+ -1 is not encountered (highest < -1), we insert above last leaf.
+ Otherwise, we insert above the node with the highest value which was not
+ equal to the one of its parent + 1.
+
+ - the "eb_next" primitive walks from left to right, which means from lower
+ to higher keys. It returns duplicates in the order they were inserted.
+ The "eb_first" primitive returns the left-most entry.
+
+ - the "eb_prev" primitive walks from right to left, which means from
+ higher to lower keys. It returns duplicates in the opposite order they
+ were inserted. The "eb_last" primitive returns the right-most entry.
+
+ */
+
+
+#include <stdlib.h>
+
+/* Note: we never need to run fls on null keys, so we can optimize the fls
+ * function by removing a conditional jump.
+ */
+#if defined(__i386__)
+static inline int flsnz(int x)
+{
+ int r;
+ __asm__("bsrl %1,%0\n"
+ : "=r" (r) : "rm" (x));
+ return r+1;
+}
+#else
+// returns 1 to 32 for 1<<0 to 1<<31. Undefined for 0.
+#define flsnz(___a) ({ \
+ register int ___x, ___bits = 0; \
+ ___x = (___a); \
+ if (___x & 0xffff0000) { ___x &= 0xffff0000; ___bits += 16;} \
+ if (___x & 0xff00ff00) { ___x &= 0xff00ff00; ___bits += 8;} \
+ if (___x & 0xf0f0f0f0) { ___x &= 0xf0f0f0f0; ___bits += 4;} \
+ if (___x & 0xcccccccc) { ___x &= 0xcccccccc; ___bits += 2;} \
+ if (___x & 0xaaaaaaaa) { ___x &= 0xaaaaaaaa; ___bits += 1;} \
+ ___bits + 1; \
+ })
+#endif
+
+static inline int fls64(unsigned long long x)
+{
+ unsigned int h;
+ unsigned int bits = 32;
+
+ h = x >> 32;
+ if (!h) {
+ h = x;
+ bits = 0;
+ }
+ return flsnz(h) + bits;
+}
+
+#define fls_auto(x) ((sizeof(x) > 4) ? fls64(x) : flsnz(x))
+
+/* Linux-like "container_of". It returns a pointer to the structure of type
+ * <type> which has its member <name> stored at address <ptr>.
+ */
+#ifndef container_of
+#define container_of(ptr, type, name) ((type *)(((void *)(ptr)) - ((long)&((type *)0)->name)))
+#endif
+
+/*
+ * Gcc >= 3 provides the ability for the program to give hints to the compiler
+ * about what branch of an if is most likely to be taken. This helps the
+ * compiler produce the most compact critical paths, which is generally better
+ * for the cache and to reduce the number of jumps. Be very careful not to use
+ * this in inline functions, because the code reordering it causes very often
+ * has a negative impact on the calling functions.
+ */
+#if __GNUC__ < 3 && !defined(__builtin_expect)
+#define __builtin_expect(x,y) (x)
+#endif
+
+#ifndef likely
+#define likely(x) (__builtin_expect((x) != 0, 1))
+#define unlikely(x) (__builtin_expect((x) != 0, 0))
+#endif
+
+/* Support passing function parameters in registers. For this, the
+ * CONFIG_EBTREE_REGPARM macro has to be set to the maximal number of registers
+ * allowed. Some functions have intentionally received a regparm lower than
+ * their parameter count, it is in order to avoid register clobbering where
+ * they are called.
+ */
+#ifndef REGPRM1
+#if CONFIG_EBTREE_REGPARM >= 1
+#define REGPRM1 __attribute__((regparm(1)))
+#else
+#define REGPRM1
+#endif
+#endif
+
+#ifndef REGPRM2
+#if CONFIG_EBTREE_REGPARM >= 2
+#define REGPRM2 __attribute__((regparm(2)))
+#else
+#define REGPRM2 REGPRM1
+#endif
+#endif
+
+#ifndef REGPRM3
+#if CONFIG_EBTREE_REGPARM >= 3
+#define REGPRM3 __attribute__((regparm(3)))
+#else
+#define REGPRM3 REGPRM2
+#endif
+#endif
+
+/* Number of bits per node, and number of leaves per node */
+#define EB_NODE_BITS 1
+#define EB_NODE_BRANCHES (1 << EB_NODE_BITS)
+#define EB_NODE_BRANCH_MASK (EB_NODE_BRANCHES - 1)
+
+/* Be careful not to tweak those values. The walking code is optimized for NULL
+ * detection on the assumption that the following values are intact.
+ */
+#define EB_LEFT 0
+#define EB_RGHT 1
+#define EB_LEAF 0
+#define EB_NODE 1
+
+/* This is the same as an eb_node pointer, except that the lower bit embeds
+ * a tag. See eb_dotag()/eb_untag()/eb_gettag(). This tag has two meanings :
+ * - 0=left, 1=right to designate the parent's branch for leaf_p/node_p
+ * - 0=link, 1=leaf to designate the branch's type for branch[]
+ */
+typedef void eb_troot_t;
+
+/* The eb_root connects the node which contains it, to two nodes below it, one
+ * of which may be the same node. At the top of the tree, we use an eb_root
+ * too, which always has its right branch NULL.
+ */
+struct eb_root {
+ eb_troot_t *b[EB_NODE_BRANCHES]; /* left and right branches */
+};
+
+/* The eb_node contains the two parts, one for the leaf, which always exists,
+ * and one for the node, which remains unused in the very first node inserted
+ * into the tree. This structure is 20 bytes per node on 32-bit machines. Do
+ * not change the order, benchmarks have shown that it's optimal this way.
+ */
+struct eb_node {
+ struct eb_root branches; /* branches, must be at the beginning */
+ eb_troot_t *node_p; /* link node's parent */
+ eb_troot_t *leaf_p; /* leaf node's parent */
+ int bit; /* link's bit position. */
+};
+
+/* Return the structure of type <type> whose member <member> points to <ptr> */
+#define eb_entry(ptr, type, member) container_of(ptr, type, member)
+
+/* The root of a tree is an eb_root initialized with both pointers NULL.
+ * During its life, only the left pointer will change. The right one will
+ * always remain NULL, which is the way we detect it.
+ */
+#define EB_ROOT \
+ (struct eb_root) { \
+ .b = {[0] = NULL, [1] = NULL }, \
+ }
+
+#define EB_TREE_HEAD(name) \
+ struct eb_root name = EB_ROOT
+
+
+/***************************************\
+ * Private functions. Not for end-user *
+\***************************************/
+
+/* Converts a root pointer to its equivalent eb_troot_t pointer,
+ * ready to be stored in ->branch[], leaf_p or node_p. NULL is not
+ * conserved. To be used with EB_LEAF, EB_NODE, EB_LEFT or EB_RGHT in <tag>.
+ */
+static inline eb_troot_t *eb_dotag(const struct eb_root *root, const int tag)
+{
+ return (eb_troot_t *)((void *)root + tag);
+}
+
+/* Converts an eb_troot_t pointer pointer to its equivalent eb_root pointer,
+ * for use with pointers from ->branch[], leaf_p or node_p. NULL is conserved
+ * as long as the tree is not corrupted. To be used with EB_LEAF, EB_NODE,
+ * EB_LEFT or EB_RGHT in <tag>.
+ */
+static inline struct eb_root *eb_untag(const eb_troot_t *troot, const int tag)
+{
+ return (struct eb_root *)((void *)troot - tag);
+}
+
+/* returns the tag associated with an eb_troot_t pointer */
+static inline int eb_gettag(eb_troot_t *troot)
+{
+ return (unsigned long)troot & 1;
+}
+
+/* Converts a root pointer to its equivalent eb_troot_t pointer and clears the
+ * tag, no matter what its value was.
+ */
+static inline struct eb_root *eb_clrtag(const eb_troot_t *troot)
+{
+ return (struct eb_root *)((unsigned long)troot & ~1UL);
+}
+
+/* Returns a pointer to the eb_node holding <root> */
+static inline struct eb_node *eb_root_to_node(struct eb_root *root)
+{
+ return container_of(root, struct eb_node, branches);
+}
+
+/* Walks down starting at root pointer <start>, and always walking on side
+ * <side>. It either returns the node hosting the first leaf on that side,
+ * or NULL if no leaf is found. <start> may either be NULL or a branch pointer.
+ * The pointer to the leaf (or NULL) is returned.
+ */
+static inline struct eb_node *eb_walk_down(eb_troot_t *start, unsigned int side)
+{
+ /* A NULL pointer on an empty tree root will be returned as-is */
+ while (eb_gettag(start) == EB_NODE)
+ start = (eb_untag(start, EB_NODE))->b[side];
+ /* NULL is left untouched (root==eb_node, EB_LEAF==0) */
+ return eb_root_to_node(eb_untag(start, EB_LEAF));
+}
+
+/* This function is used to build a tree of duplicates by adding a new node to
+ * a subtree of at least 2 entries. It will probably never be needed inlined,
+ * and it is not for end-user.
+ */
+static inline struct eb_node *
+__eb_insert_dup(struct eb_node *sub, struct eb_node *new)
+{
+ struct eb_node *head = sub;
+
+ struct eb_troot *new_left = eb_dotag(&new->branches, EB_LEFT);
+ struct eb_troot *new_rght = eb_dotag(&new->branches, EB_RGHT);
+ struct eb_troot *new_leaf = eb_dotag(&new->branches, EB_LEAF);
+
+ /* first, identify the deepest hole on the right branch */
+ while (eb_gettag(head->branches.b[EB_RGHT]) != EB_LEAF) {
+ struct eb_node *last = head;
+ head = container_of(eb_untag(head->branches.b[EB_RGHT], EB_NODE),
+ struct eb_node, branches);
+ if (head->bit > last->bit + 1)
+ sub = head; /* there's a hole here */
+ }
+
+ /* Here we have a leaf attached to (head)->b[EB_RGHT] */
+ if (head->bit < -1) {
+ /* A hole exists just before the leaf, we insert there */
+ new->bit = -1;
+ sub = container_of(eb_untag(head->branches.b[EB_RGHT], EB_LEAF),
+ struct eb_node, branches);
+ head->branches.b[EB_RGHT] = eb_dotag(&new->branches, EB_NODE);
+
+ new->node_p = sub->leaf_p;
+ new->leaf_p = new_rght;
+ sub->leaf_p = new_left;
+ new->branches.b[EB_LEFT] = eb_dotag(&sub->branches, EB_LEAF);
+ new->branches.b[EB_RGHT] = new_leaf;
+ return new;
+ } else {
+ int side;
+ /* No hole was found before a leaf. We have to insert above
+ * <sub>. Note that we cannot be certain that <sub> is attached
+ * to the right of its parent, as this is only true if <sub>
+ * is inside the dup tree, not at the head.
+ */
+ new->bit = sub->bit - 1; /* install at the lowest level */
+ side = eb_gettag(sub->node_p);
+ head = container_of(eb_untag(sub->node_p, side), struct eb_node, branches);
+ head->branches.b[side] = eb_dotag(&new->branches, EB_NODE);
+
+ new->node_p = sub->node_p;
+ new->leaf_p = new_rght;
+ sub->node_p = new_left;
+ new->branches.b[EB_LEFT] = eb_dotag(&sub->branches, EB_NODE);
+ new->branches.b[EB_RGHT] = new_leaf;
+ return new;
+ }
+}
+
+
+/**************************************\
+ * Public functions, for the end-user *
+\**************************************/
+
+/* Return the first leaf in the tree starting at <root>, or NULL if none */
+static inline struct eb_node *eb_first(struct eb_root *root)
+{
+ return eb_walk_down(root->b[0], EB_LEFT);
+}
+
+/* Return the last leaf in the tree starting at <root>, or NULL if none */
+static inline struct eb_node *eb_last(struct eb_root *root)
+{
+ return eb_walk_down(root->b[0], EB_RGHT);
+}
+
+/* Return previous leaf node before an existing leaf node, or NULL if none. */
+static inline struct eb_node *eb_prev(struct eb_node *node)
+{
+ eb_troot_t *t = node->leaf_p;
+
+ while (eb_gettag(t) == EB_LEFT) {
+ /* Walking up from left branch. We must ensure that we never
+ * walk beyond root.
+ */
+ if (unlikely((eb_untag(t, EB_LEFT))->b[EB_RGHT] == NULL))
+ return NULL;
+ t = (eb_root_to_node(eb_untag(t, EB_LEFT)))->node_p;
+ }
+ /* Note that <t> cannot be NULL at this stage */
+ t = (eb_untag(t, EB_RGHT))->b[EB_LEFT];
+ return eb_walk_down(t, EB_RGHT);
+}
+
+/* Return next leaf node after an existing leaf node, or NULL if none. */
+static inline struct eb_node *eb_next(struct eb_node *node)
+{
+ eb_troot_t *t = node->leaf_p;
+
+ while (eb_gettag(t) != EB_LEFT)
+ /* Walking up from right branch, so we cannot be below root */
+ t = (eb_root_to_node(eb_untag(t, EB_RGHT)))->node_p;
+
+ /* Note that <t> cannot be NULL at this stage */
+ t = (eb_untag(t, EB_LEFT))->b[EB_RGHT];
+ return eb_walk_down(t, EB_LEFT);
+}
+
+/* Return previous leaf node before an existing leaf node, skipping duplicates,
+ * or NULL if none. */
+static inline struct eb_node *eb_prev_unique(struct eb_node *node)
+{
+ eb_troot_t *t = node->leaf_p;
+
+ while (1) {
+ if (eb_gettag(t) != EB_LEFT) {
+ node = eb_root_to_node(eb_untag(t, EB_RGHT));
+ /* if we're right and not in duplicates, stop here */
+ if (node->bit >= 0)
+ break;
+ t = node->node_p;
+ }
+ else {
+ /* Walking up from left branch. We must ensure that we never
+ * walk beyond root.
+ */
+ if (unlikely((eb_untag(t, EB_LEFT))->b[EB_RGHT] == NULL))
+ return NULL;
+ t = (eb_root_to_node(eb_untag(t, EB_LEFT)))->node_p;
+ }
+ }
+ /* Note that <t> cannot be NULL at this stage */
+ t = (eb_untag(t, EB_RGHT))->b[EB_LEFT];
+ return eb_walk_down(t, EB_RGHT);
+}
+
+/* Return next leaf node after an existing leaf node, skipping duplicates, or
+ * NULL if none.
+ */
+static inline struct eb_node *eb_next_unique(struct eb_node *node)
+{
+ eb_troot_t *t = node->leaf_p;
+
+ while (1) {
+ if (eb_gettag(t) == EB_LEFT) {
+ if (unlikely((eb_untag(t, EB_LEFT))->b[EB_RGHT] == NULL))
+ return NULL; /* we reached root */
+ node = eb_root_to_node(eb_untag(t, EB_LEFT));
+ /* if we're left and not in duplicates, stop here */
+ if (node->bit >= 0)
+ break;
+ t = node->node_p;
+ }
+ else {
+ /* Walking up from right branch, so we cannot be below root */
+ t = (eb_root_to_node(eb_untag(t, EB_RGHT)))->node_p;
+ }
+ }
+
+ /* Note that <t> cannot be NULL at this stage */
+ t = (eb_untag(t, EB_LEFT))->b[EB_RGHT];
+ return eb_walk_down(t, EB_LEFT);
+}
+
+
+/* Removes a leaf node from the tree if it was still in it. Marks the node
+ * as unlinked.
+ */
+static inline void __eb_delete(struct eb_node *node)
+{
+ __label__ delete_unlink;
+ unsigned int pside, gpside, sibtype;
+ struct eb_node *parent;
+ struct eb_root *gparent;
+
+ if (!node->leaf_p)
+ return;
+
+ /* we need the parent, our side, and the grand parent */
+ pside = eb_gettag(node->leaf_p);
+ parent = eb_root_to_node(eb_untag(node->leaf_p, pside));
+
+ /* We likely have to release the parent link, unless it's the root,
+ * in which case we only set our branch to NULL. Note that we can
+ * only be attached to the root by its left branch.
+ */
+
+ if (parent->branches.b[EB_RGHT] == NULL) {
+ /* we're just below the root, it's trivial. */
+ parent->branches.b[EB_LEFT] = NULL;
+ goto delete_unlink;
+ }
+
+ /* To release our parent, we have to identify our sibling, and reparent
+ * it directly to/from the grand parent. Note that the sibling can
+ * either be a link or a leaf.
+ */
+
+ gpside = eb_gettag(parent->node_p);
+ gparent = eb_untag(parent->node_p, gpside);
+
+ gparent->b[gpside] = parent->branches.b[!pside];
+ sibtype = eb_gettag(gparent->b[gpside]);
+
+ if (sibtype == EB_LEAF) {
+ eb_root_to_node(eb_untag(gparent->b[gpside], EB_LEAF))->leaf_p =
+ eb_dotag(gparent, gpside);
+ } else {
+ eb_root_to_node(eb_untag(gparent->b[gpside], EB_NODE))->node_p =
+ eb_dotag(gparent, gpside);
+ }
+ /* Mark the parent unused. Note that we do not check if the parent is
+ * our own node, but that's not a problem because if it is, it will be
+ * marked unused at the same time, which we'll use below to know we can
+ * safely remove it.
+ */
+ parent->node_p = NULL;
+
+ /* The parent node has been detached, and is currently unused. It may
+ * belong to another node, so we cannot remove it that way. Also, our
+ * own node part might still be used. so we can use this spare node
+ * to replace ours if needed.
+ */
+
+ /* If our link part is unused, we can safely exit now */
+ if (!node->node_p)
+ goto delete_unlink;
+
+ /* From now on, <node> and <parent> are necessarily different, and the
+ * <node>'s node part is in use. By definition, <parent> is at least
+ * below <node>, so keeping its key for the bit string is OK.
+ */
+
+ parent->node_p = node->node_p;
+ parent->branches = node->branches;
+ parent->bit = node->bit;
+
+ /* We must now update the new node's parent... */
+ gpside = eb_gettag(parent->node_p);
+ gparent = eb_untag(parent->node_p, gpside);
+ gparent->b[gpside] = eb_dotag(&parent->branches, EB_NODE);
+
+ /* ... and its branches */
+ for (pside = 0; pside <= 1; pside++) {
+ if (eb_gettag(parent->branches.b[pside]) == EB_NODE) {
+ eb_root_to_node(eb_untag(parent->branches.b[pside], EB_NODE))->node_p =
+ eb_dotag(&parent->branches, pside);
+ } else {
+ eb_root_to_node(eb_untag(parent->branches.b[pside], EB_LEAF))->leaf_p =
+ eb_dotag(&parent->branches, pside);
+ }
+ }
+ delete_unlink:
+ /* Now the node has been completely unlinked */
+ node->leaf_p = NULL;
+ return; /* tree is not empty yet */
+}
+
+/* These functions are declared in ebtree.c */
+void eb_delete(struct eb_node *node);
+REGPRM1 struct eb_node *eb_insert_dup(struct eb_node *sub, struct eb_node *new);
+
+
+/*
+ * Local variables:
+ * c-indent-level: 8
+ * c-basic-offset: 8
+ * End:
+ */