[MINOR] update ebtree to version 4.1

Ebtree version 4.1 brings lookup by ranges. This will be useful for
the scheduler.

include/common/eb32tree.h

@@ -100,6 +100,7 @@ static inline void eb32_delete(struct eb32_node *eb32)
  */
 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_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);
 
@@ -122,6 +123,7 @@ 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))
@@ -139,7 +141,8 @@ static forceinline struct eb32_node *__eb32_lookup(struct eb_root *root, u32 x)
 		node = container_of(eb_untag(troot, EB_NODE),
 				    struct eb32_node, node.branches);
 
-		if (x == node->key) {
+		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.
@@ -154,6 +157,9 @@ static forceinline struct eb32_node *__eb32_lookup(struct eb_root *root, u32 x)
 			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];
 	}
 }
@@ -167,6 +173,7 @@ 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))
@@ -184,7 +191,8 @@ static forceinline struct eb32_node *__eb32i_lookup(struct eb_root *root, s32 x)
 		node = container_of(eb_untag(troot, EB_NODE),
 				    struct eb32_node, node.branches);
 
-		if (x == node->key) {
+		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.
@@ -199,6 +207,9 @@ static forceinline struct eb32_node *__eb32i_lookup(struct eb_root *root, s32 x)
 			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];
 	}
 }

include/common/eb64tree.h

@@ -122,6 +122,7 @@ static forceinline struct eb64_node *__eb64_lookup(struct eb_root *root, u64 x)
 {
 	struct eb64_node *node;
 	eb_troot_t *troot;
+	u64 y;
 
 	troot = root->b[EB_LEFT];
 	if (unlikely(troot == NULL))
@@ -139,7 +140,8 @@ static forceinline struct eb64_node *__eb64_lookup(struct eb_root *root, u64 x)
 		node = container_of(eb_untag(troot, EB_NODE),
 				    struct eb64_node, node.branches);
 
-		if (x == node->key) {
+		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.
@@ -154,6 +156,9 @@ static forceinline struct eb64_node *__eb64_lookup(struct eb_root *root, u64 x)
 			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];
 	}
 }
@@ -167,6 +172,7 @@ static forceinline struct eb64_node *__eb64i_lookup(struct eb_root *root, s64 x)
 	struct eb64_node *node;
 	eb_troot_t *troot;
 	u64 key = x ^ (1ULL << 63);
+	u64 y;
 
 	troot = root->b[EB_LEFT];
 	if (unlikely(troot == NULL))
@@ -184,7 +190,8 @@ static forceinline struct eb64_node *__eb64i_lookup(struct eb_root *root, s64 x)
 		node = container_of(eb_untag(troot, EB_NODE),
 				    struct eb64_node, node.branches);
 
-		if (x == node->key) {
+		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.
@@ -199,6 +206,9 @@ static forceinline struct eb64_node *__eb64i_lookup(struct eb_root *root, s64 x)
 			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];
 	}
 }

include/common/ebpttree.h

@@ -123,6 +123,7 @@ static forceinline struct ebpt_node *__ebpt_lookup(struct eb_root *root, void *x
 {
 	struct ebpt_node *node;
 	eb_troot_t *troot;
+	ptr_t y;
 
 	troot = root->b[EB_LEFT];
 	if (unlikely(troot == NULL))
@@ -140,7 +141,8 @@ static forceinline struct ebpt_node *__ebpt_lookup(struct eb_root *root, void *x
 		node = container_of(eb_untag(troot, EB_NODE),
 				    struct ebpt_node, node.branches);
 
-		if (x == node->key) {
+		y = (ptr_t)node->key ^ (ptr_t)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.
@@ -155,6 +157,9 @@ static forceinline struct ebpt_node *__ebpt_lookup(struct eb_root *root, void *x
 			return node;
 		}
 
+		if ((y >> node->node.bit) >= EB_NODE_BRANCHES)
+			return NULL; /* no more common bits */
+
 		troot = node->node.branches.b[((ptr_t)x >> node->node.bit) & EB_NODE_BRANCH_MASK];
 	}
 }

src/eb32tree.c

@@ -1,6 +1,6 @@
 /*
  * Elastic Binary Trees - exported functions for operations on 32bit nodes.
- * (C) 2002-2007 - Willy Tarreau <w@1wt.eu>
+ * (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
@@ -40,3 +40,90 @@ REGPRM2 struct eb32_node *eb32i_lookup(struct eb_root *root, s32 x)
 {
 	return __eb32i_lookup(root, x);
 }
+
+/*
+ * Find the first occurrence of the lowest key in the tree <root>, which is
+ * equal to or greater than <x>. NULL is returned is no key matches.
+ */
+REGPRM2 struct eb32_node *eb32_lookup_ge(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)) {
+			/* We reached a leaf, which means that the whole upper
+			 * parts were common. We will return either the current
+			 * node or its next one if the former is too small.
+			 */
+			node = container_of(eb_untag(troot, EB_LEAF),
+					    struct eb32_node, node.branches);
+			if (node->key >= x)
+				return node;
+			/* return next */
+			troot = node->node.leaf_p;
+			break;
+		}
+		node = container_of(eb_untag(troot, EB_NODE),
+				    struct eb32_node, node.branches);
+
+		if (node->node.bit < 0) {
+			/* We're at the top of a dup tree. Either we got a
+			 * matching value and we return the leftmost node, or
+			 * we don't and we skip the whole subtree to return the
+			 * next node after the subtree. Note that since we're
+			 * at the top of the dup tree, we can simply return the
+			 * next node without first trying to escape from the
+			 * tree.
+			 */
+			if (node->key >= x) {
+				troot = node->node.branches.b[EB_LEFT];
+				while (eb_gettag(troot) != EB_LEAF)
+					troot = (eb_untag(troot, EB_NODE))->b[EB_LEFT];
+				return container_of(eb_untag(troot, EB_LEAF),
+						    struct eb32_node, node.branches);
+			}
+			/* return next */
+			troot = node->node.node_p;
+			break;
+		}
+
+		if (((x ^ node->key) >> node->node.bit) >= EB_NODE_BRANCHES) {
+			/* No more common bits at all. Either this node is too
+			 * large and we need to get its lowest value, or it is too
+			 * small, and we need to get the next value.
+			 */
+			if ((node->key >> node->node.bit) > (x >> node->node.bit)) {
+				troot = node->node.branches.b[EB_LEFT];
+				return eb32_entry(eb_walk_down(troot, EB_LEFT), struct eb32_node, node);
+			}
+
+			/* Further values will be too low here, so return the next
+			 * unique node (if it exists).
+			 */
+			troot = node->node.node_p;
+			break;
+		}
+		troot = node->node.branches.b[(x >> node->node.bit) & EB_NODE_BRANCH_MASK];
+	}
+
+	/* If we get here, it means we want to report next node after the
+	 * current one which is not below. <troot> is already initialised
+	 * to the parent's branches.
+	 */
+	while (eb_gettag(troot) != EB_LEFT)
+		/* Walking up from right branch, so we cannot be below root */
+		troot = (eb_root_to_node(eb_untag(troot, EB_RGHT)))->node_p;
+
+	/* Note that <troot> cannot be NULL at this stage */
+	troot = (eb_untag(troot, EB_LEFT))->b[EB_RGHT];
+	if (eb_clrtag(troot) == NULL)
+		return NULL;
+
+	node = eb32_entry(eb_walk_down(troot, EB_LEFT), struct eb32_node, node);
+	return node;
+}