[IMPORT] import ebtree v5.0 into directory ebtree/

We needed to upgrade ebtree to v5.0 to support string indexing,
and it was getting very painful to have it split across 2 dirs
and to have to patch it. Now we just have to copy the .c and .h
files to the right place.
diff --git a/ebtree/eb32tree.h b/ebtree/eb32tree.h
new file mode 100644
index 0000000..037c458
--- /dev/null
+++ b/ebtree/eb32tree.h
@@ -0,0 +1,548 @@
+/*
+ * Elastic Binary Trees - macros and structures for operations on 32bit nodes.
+ * Version 5.0
+ * (C) 2002-2009 - 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
+ */
+
+#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)
+
+#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_lookup_le(struct eb_root *root, u32 x);
+REGPRM2 struct eb32_node *eb32_lookup_ge(struct eb_root *root, u32 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 forceinline 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 forceinline struct eb32_node *__eb32_lookup(struct eb_root *root, u32 x)
+{
+	struct eb32_node *node;
+	eb_troot_t *troot;
+	u32 y;
+
+	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);
+
+		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->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->node.bit) >= EB_NODE_BRANCHES)
+			return NULL; /* no more common bits */
+
+		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 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;
+
+	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);
+
+		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->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->node.bit) >= EB_NODE_BRANCHES)
+			return NULL; /* no more common bits */
+
+		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.
+ * 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;
+	u32 newkey; /* caching the key saves approximately one cycle */
+	eb_troot_t *root_right = root;
+
+	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 (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 {
+				/* we may refuse to duplicate this key if the tree is
+				 * tagged as containing only unique keys.
+				 */
+				if ((new->key == old->key) && eb_gettag(root_right))
+					return old;
+
+				/* 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. 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;
+	int newkey; /* caching the key saves approximately one cycle */
+	eb_troot_t *root_right = root;
+
+	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 (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 {
+				/* we may refuse to duplicate this key if the tree is
+				 * tagged as containing only unique keys.
+				 */
+				if ((new->key == old->key) && eb_gettag(root_right))
+					return old;
+
+				/* 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;
+}
+
+#endif /* _EB32_TREE_H */