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-rw-r--r--src/search/tsearch_avl.c204
1 files changed, 0 insertions, 204 deletions
diff --git a/src/search/tsearch_avl.c b/src/search/tsearch_avl.c
deleted file mode 100644
index 57194c84..00000000
--- a/src/search/tsearch_avl.c
+++ /dev/null
@@ -1,204 +0,0 @@
-#include <stdlib.h>
-#include <search.h>
-
-/*
-avl tree implementation using recursive functions
-the height of an n node tree is less than 1.44*log2(n+2)-1
-(so the max recursion depth in case of a tree with 2^32 nodes is 45)
-*/
-
-struct node {
-	const void *key;
-	struct node *left;
-	struct node *right;
-	int height;
-};
-
-static int delta(struct node *n) {
-	return (n->left ? n->left->height:0) - (n->right ? n->right->height:0);
-}
-
-static void updateheight(struct node *n) {
-	n->height = 0;
-	if (n->left && n->left->height > n->height)
-		n->height = n->left->height;
-	if (n->right && n->right->height > n->height)
-		n->height = n->right->height;
-	n->height++;
-}
-
-static struct node *rotl(struct node *n) {
-	struct node *r = n->right;
-	n->right = r->left;
-	r->left = n;
-	updateheight(n);
-	updateheight(r);
-	return r;
-}
-
-static struct node *rotr(struct node *n) {
-	struct node *l = n->left;
-	n->left = l->right;
-	l->right = n;
-	updateheight(n);
-	updateheight(l);
-	return l;
-}
-
-static struct node *balance(struct node *n) {
-	int d = delta(n);
-
-	if (d < -1) {
-		if (delta(n->right) > 0)
-			n->right = rotr(n->right);
-		return rotl(n);
-	} else if (d > 1) {
-		if (delta(n->left) < 0)
-			n->left = rotl(n->left);
-		return rotr(n);
-	}
-	updateheight(n);
-	return n;
-}
-
-static struct node *find(struct node *n, const void *k,
-	int (*cmp)(const void *, const void *))
-{
-	int c;
-
-	if (!n)
-		return 0;
-	c = cmp(k, n->key);
-	if (c == 0)
-		return n;
-	if (c < 0)
-		return find(n->left, k, cmp);
-	else
-		return find(n->right, k, cmp);
-}
-
-static struct node *insert(struct node *n, const void *k,
-	int (*cmp)(const void *, const void *), struct node **found)
-{
-	struct node *r;
-	int c;
-
-	if (!n) {
-		n = malloc(sizeof *n);
-		if (n) {
-			n->key = k;
-			n->left = n->right = 0;
-			n->height = 1;
-		}
-		*found = n;
-		return n;
-	}
-	c = cmp(k, n->key);
-	if (c == 0) {
-		*found = n;
-		return 0;
-	}
-	r = insert(c < 0 ? n->left : n->right, k, cmp, found);
-	if (r) {
-		if (c < 0)
-			n->left = r;
-		else
-			n->right = r;
-		r = balance(n);
-	}
-	return r;
-}
-
-static struct node *remove_rightmost(struct node *n, struct node **rightmost)
-{
-	if (!n->right) {
-		*rightmost = n;
-		return n->left;
-	}
-	n->right = remove_rightmost(n->right, rightmost);
-	return balance(n);
-}
-
-static struct node *remove(struct node **n, const void *k,
-	int (*cmp)(const void *, const void *), struct node *parent)
-{
-	int c;
-
-	if (!*n)
-		return 0;
-	c = cmp(k, (*n)->key);
-	if (c == 0) {
-		struct node *r = *n;
-		if (r->left) {
-			r->left = remove_rightmost(r->left, n);
-			(*n)->left = r->left;
-			(*n)->right = r->right;
-			*n = balance(*n);
-		} else
-			*n = r->right;
-		free(r);
-		return parent;
-	}
-	if (c < 0)
-		parent = remove(&(*n)->left, k, cmp, *n);
-	else
-		parent = remove(&(*n)->right, k, cmp, *n);
-	if (parent)
-		*n = balance(*n);
-	return parent;
-}
-
-void *tdelete(const void *restrict key, void **restrict rootp,
-	int(*compar)(const void *, const void *))
-{
-	if (!rootp)
-		return 0;
-	struct node *n = *rootp;
-	struct node *ret;
-	/* last argument is arbitrary non-null pointer
-	   which is returned when the root node is deleted */
-	ret = remove(&n, key, compar, n);
-	*rootp = n;
-	return ret;
-}
-
-void *tfind(const void *key, void *const *rootp,
-	int(*compar)(const void *, const void *))
-{
-	if (!rootp)
-		return 0;
-	return find(*rootp, key, compar);
-}
-
-void *tsearch(const void *key, void **rootp,
-	int (*compar)(const void *, const void *))
-{
-	struct node *update;
-	struct node *ret;
-	if (!rootp)
-		return 0;
-	update = insert(*rootp, key, compar, &ret);
-	if (update)
-		*rootp = update;
-	return ret;
-}
-
-static void walk(const struct node *r, void (*action)(const void *, VISIT, int), int d)
-{
-	if (r == 0)
-		return;
-	if (r->left == 0 && r->right == 0)
-		action(r, leaf, d);
-	else {
-		action(r, preorder, d);
-		walk(r->left, action, d+1);
-		action(r, postorder, d);
-		walk(r->right, action, d+1);
-		action(r, endorder, d);
-	}
-}
-
-void twalk(const void *root, void (*action)(const void *, VISIT, int))
-{
-	walk(root, action, 0);
-}