sandbox: btree: add macros to define custom btree inserter

tree keys are no longer stored in btree_node_t. The tree user is responsible for
defining their own node type that includes btree_node_t, and a comparator for the nodes.

sandbox/btree/btree.c

@@ -4,14 +4,6 @@
 #include <stdio.h>
 #include <assert.h>
 
-#define BTREE_VERBOSE
-
-#ifdef BTREE_VERBOSE
-#define debug_msg(...) printf(__VA_ARGS__)
-#else
-#define debug_msg(...)
-#endif
-
 #define MAX(a, b) ((a) > (b) ? (a) : (b))
 #define MIN(a, b) ((a) < (b) ? (a) : (b))
 
@@ -27,8 +19,6 @@
 
 #define HEIGHT(x) ((x) ? (x)->b_height : 0)
 
-extern void btree_print(btree_node_t *, int);
-
 static inline void update_height(btree_node_t *x)
 {
 	x->b_height = MAX(HEIGHT(x->b_left), HEIGHT((x->b_right))) + 1;
@@ -65,8 +55,6 @@ static void rotate_left(btree_t *tree, btree_node_t *x)
 		assert(x == x->b_parent->b_left || x == x->b_parent->b_right);
 	}
 
-	debug_msg("  rotate_left(x: %llu, y: %llu)\n", x->b_key, y->b_key);
-
 	btree_node_t *p = x->b_parent;
 
 	if (y->b_left) {
@@ -78,10 +66,8 @@ static void rotate_left(btree_t *tree, btree_node_t *x)
 	if (!p) {
 		tree->b_root = y;
 	} else if (x == p->b_left) {
-		debug_msg("    %llu->left was %llu, now %llu\n", p->b_key, p->b_left->b_key, y->b_key);
 		p->b_left = y;
 	} else {
-		debug_msg("    %llu->right was %llu, now %llu\n", p->b_key, p->b_right->b_key, y->b_key);
 		p->b_right = y;
 	}
 
@@ -110,8 +96,6 @@ static void rotate_right(btree_t *tree, btree_node_t *y)
 		assert(y == y->b_parent->b_left || y == y->b_parent->b_right);
 	}
 
-	debug_msg("  rotate_right(y: %llu, x: %llu)\n", y->b_key, x->b_key);
-
 	btree_node_t *p = y->b_parent;
 
 	if (x->b_right) {
@@ -123,10 +107,8 @@ static void rotate_right(btree_t *tree, btree_node_t *y)
 	if (!p) {
 		tree->b_root = x;
 	} else if (y == p->b_left) {
-		debug_msg("    %llu->left was %llu, now %llu\n", p->b_key, p->b_left->b_key, x->b_key);
 		p->b_left = x;
 	} else {
-		debug_msg("    %llu->right was %llu, now %llu\n", p->b_key, p->b_right->b_key, x->b_key);
 		p->b_right = x;
 	}
 
@@ -139,13 +121,10 @@ static void rotate_double_left(btree_t *tree, btree_node_t *z)
 {
 	btree_node_t *x = z->b_right;
 	btree_node_t *y = x->b_left;
-	debug_msg("rotate_double_left(z: %llu, x: %llu, y: %llu) {\n", z->b_key, x->b_key, y->b_key);
 
 	rotate_right(tree, x);
 	rotate_left(tree, z);
 
-	debug_msg("}\n");
-
 	update_height(z);
 	update_height(x);
 
@@ -159,13 +138,10 @@ static void rotate_double_right(btree_t *tree, btree_node_t *z)
 {
 	btree_node_t *x = z->b_left;
 	btree_node_t *y = x->b_right;
-	debug_msg("rotate_double_right(z: %llu, x: %llu, y: %llu) {\n", z->b_key, x->b_key, y->b_key);
 
 	rotate_left(tree, x);
 	rotate_right(tree, z);
 
-	debug_msg("}\n");
-
 	update_height(z);
 	update_height(x);
 
@@ -216,15 +192,11 @@ next_ancestor:
 
 static void delete_fixup(btree_t *tree, btree_node_t *w)
 {
-	printf("delete_fixup(%llu)\n", w->b_key);
 	btree_node_t *z = w;
 
 	int nr_rotations = 0;
 
 	while (z) {
-		printf("bf(z)=%d\n", bf(z));
-		printf("bf(z->b_left)=%d\n", bf(z->b_left));
-
 		if (bf(z) > 1) {
 			if (bf(z->b_right) >= 0) {
 				rotate_left(tree, z);
@@ -246,10 +218,22 @@ static void delete_fixup(btree_t *tree, btree_node_t *w)
 	}
 }
 
+void btree_insert_fixup(btree_t *tree, btree_node_t *node)
+{
+	node->b_height = 0;
+
+	btree_node_t *cur = node;
+	while (cur) {
+		update_height(cur);
+		cur = cur->b_parent;
+	}
+
+	insert_fixup(tree, node);
+}
+
+#if 0
 void btree_insert(btree_t *tree, btree_node_t *node)
 {
-	node->b_owner = tree;
-
 	if (!tree->b_root) {
 		tree->b_root = node;
 		node->b_parent = NULL;
@@ -262,7 +246,6 @@ void btree_insert(btree_t *tree, btree_node_t *node)
 		btree_node_t **nextp = NULL;
 
 		if (node->b_key == cur->b_key) {
-			node->b_owner = NULL;
 			return;
 		}
 
@@ -289,18 +272,12 @@ void btree_insert(btree_t *tree, btree_node_t *node)
 		cur = cur->b_parent;
 	}
 
-	#if 0
-	printf("##### TREE POST-INSERT, PRE-FIXUP ##############\n");
-	btree_print(tree->b_root, 0);
-	printf("################################################\n");
-	#endif
-
 	insert_fixup(tree, node);
 }
+#endif
 
 static btree_node_t *remove_node_with_no_children(btree_t *tree, btree_node_t *node)
 {
-	debug_msg("remove_node_with_no_children(%llu)\n", node->b_key);
 	btree_node_t *w = node->b_parent;
 	btree_node_t *p = node->b_parent;
 	node->b_parent = NULL;
@@ -323,7 +300,6 @@ static btree_node_t *remove_node_with_no_children(btree_t *tree, btree_node_t *n
 
 static btree_node_t *replace_node_with_one_subtree(btree_t *tree, btree_node_t *node)
 {
-	debug_msg("remove_node_with_one_subtree()\n");
 	btree_node_t *p = node->b_parent;
 	btree_node_t *z = NULL;
 
@@ -357,8 +333,6 @@ static btree_node_t *replace_node_with_one_subtree(btree_t *tree, btree_node_t *
 
 static btree_node_t *replace_node_with_two_subtrees(btree_t *tree, btree_node_t *z)
 {
-	debug_msg("remove_node_with_two_subtrees()\n");
-
 	/* x will replace z */
 	btree_node_t *x = z->b_left;
 
@@ -417,17 +391,11 @@ static btree_node_t *replace_node_with_two_subtrees(btree_t *tree, btree_node_t
 		cur = cur->b_parent;
 	}
 
-	printf("w=%llu, h:%u\n", w->b_key, w->b_height);
 	return w;
 }
 
 void btree_delete(btree_t *tree, btree_node_t *node)
 {
-	if (!node->b_owner) {
-		return;
-	}
-
-	assert(node->b_owner == tree);
 	btree_node_t *w = NULL;
 
 	if (HAS_NO_CHILDREN(node)) {
@@ -438,8 +406,6 @@ void btree_delete(btree_t *tree, btree_node_t *node)
 		w = replace_node_with_two_subtrees(tree, node);
 	}
 
-	btree_print(tree->b_root, 0);
-
 	if (w) {
 		delete_fixup(tree, w);
 	}