/*
splay_tree.c -- splay tree and linked list convenience
- Copyright (C) 2004 Guus Sliepen <guus@tinc-vpn.org>
+ Copyright (C) 2004-2006 Guus Sliepen <guus@tinc-vpn.org>
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
static splay_node_t *splay_top_down(splay_tree_t *tree, const void *data, int *result) {
splay_node_t left = {0}, right = {0};
- splay_node_t *leftbottom = &left, *rightbottom = &right, *child;
- splay_node_t *node = tree->root;
+ splay_node_t *leftbottom = &left, *rightbottom = &right, *child, *grandchild;
+ splay_node_t *root = tree->root;
int c;
- while((c = tree->compare(data, node->data))) {
- if(c < 0) {
- child = node->left;
+ if(!root) {
+ if(result)
+ *result = 0;
+ return NULL;
+ }
- if(child) {
- c = tree->compare(data, child->data);
+ while((c = tree->compare(data, root->data))) {
+ if(c < 0 && (child = root->left)) {
+ c = tree->compare(data, child->data);
+
+ if(c < 0 && (grandchild = child->left)) {
+ rightbottom->left = child;
+ child->parent = rightbottom;
+ rightbottom = child;
+
+ if((root->left = child->right))
+ child->right->parent = root;
- if(c < 0) {
- rightbottom->left = child;
- child->parent = rightbottom;
- rightbottom = child;
-
- node->left = child->right;
- child->right = node;
- node->parent = child;
- node = child->left;
- child->left = NULL;
- } else if (c > 0) {
- if(!child->right)
- break;
-
- leftbottom->right = child;
- child->parent = leftbottom;
- leftbottom = child;
-
- rightbottom->left = node;
- node->parent = rightbottom;
- rightbottom = node;
-
- node->left = NULL;
- node = child->right;
- child->right = NULL;
- } else {
- rightbottom->left = node;
- node->parent = rightbottom;
- rightbottom = node;
-
- node->left = NULL;
- child->parent = NULL;
- node = child;
- break;
- }
+ child->right = root;
+ root->parent = child;
+
+ child->left = NULL;
+ grandchild->parent = NULL;
+
+ root = grandchild;
+ } else if (c > 0 && (grandchild = child->right)) {
+ leftbottom->right = child;
+ child->parent = leftbottom;
+ leftbottom = child;
+
+ child->right = NULL;
+ grandchild->parent = NULL;
+
+ rightbottom->left = root;
+ root->parent = rightbottom;
+ rightbottom = root;
+
+ root->left = NULL;
+
+ root = grandchild;
} else {
+ rightbottom->left = root;
+ root->parent = rightbottom;
+ rightbottom = root;
+
+ root->left = NULL;
+ child->parent = NULL;
+
+ root = child;
break;
}
- } else {
- child = node->right;
+ } else if(c > 0 && (child = root->right)) {
+ c = tree->compare(data, child->data);
- if(child) {
- c = tree->compare(data, child->data);
+ if(c > 0 && (grandchild = child->right)) {
+ leftbottom->right = child;
+ child->parent = leftbottom;
+ leftbottom = child;
+
+ if((root->right = child->left))
+ child->left->parent = root;
- if(c > 0) {
- leftbottom->right = child;
- child->parent = leftbottom;
- leftbottom = child;
-
- node->right = child->left;
- child->left = node;
- node->parent = child;
- node = child->right;
- child->right = NULL;
- } else if (c < 0) {
- if(!child->left)
- break;
-
- rightbottom->left = child;
- child->parent = rightbottom;
- rightbottom = child;
-
- leftbottom->right = node;
- node->parent = leftbottom;
- leftbottom = node;
-
- node->right = NULL;
- node = child->left;
- child->left = NULL;
- } else {
- leftbottom->right = node;
- node->parent = leftbottom;
- leftbottom = node;
-
- node->right = NULL;
- child->parent = NULL;
- node = child;
- break;
- }
+ child->left = root;
+ root->parent = child;
+
+ child->right = NULL;
+ grandchild->parent = NULL;
+
+ root = grandchild;
+ } else if (c < 0 && (grandchild = child->left)) {
+ rightbottom->left = child;
+ child->parent = rightbottom;
+ rightbottom = child;
+
+ child->left = NULL;
+ grandchild->parent = NULL;
+
+ leftbottom->right = root;
+ root->parent = leftbottom;
+ leftbottom = root;
+
+ root->right = NULL;
+
+ root = grandchild;
} else {
+ leftbottom->right = root;
+ root->parent = leftbottom;
+ leftbottom = root;
+
+ root->right = NULL;
+ child->parent = NULL;
+
+ root = child;
break;
}
+ } else {
+ break;
}
}
- tree->root = node;
-
/* Merge trees */
if(left.right) {
- if(node->left) {
- leftbottom->right = node->left;
- node->left->parent = leftbottom;
+ if(root->left) {
+ leftbottom->right = root->left;
+ root->left->parent = leftbottom;
}
- node->left = left.right;
- left.right->parent = node;
+ root->left = left.right;
+ left.right->parent = root;
}
if(right.left) {
- if(node->right) {
- rightbottom->left = node->right;
- node->right->parent = rightbottom;
+ if(root->right) {
+ rightbottom->left = root->right;
+ root->right->parent = rightbottom;
}
- node->right = right.left;
- right.left->parent = node;
+ root->right = right.left;
+ right.left->parent = root;
}
+ /* Return result */
+
+ tree->root = root;
if(result)
*result = c;
- return node;
+ return tree->root;
}
-
-
+
static void splay_bottom_up(splay_tree_t *tree, splay_node_t *node) {
- splay_node_t *parent, *grandparent;
+ splay_node_t *parent, *grandparent, *greatgrandparent;
- while(node->parent) {
- parent = node->parent;
- grandparent = node->parent->parent;
-
- if(!grandparent) { /* zig */
+ while((parent = node->parent)) {
+ if(!(grandparent = parent->parent)) { /* zig */
if(node == parent->left) {
- parent->left = node->right;
+ if((parent->left = node->right))
+ parent->left->parent = parent;
node->right = parent;
} else {
- parent->right = node->left;
+ if((parent->right = node->left))
+ parent->right->parent = parent;
node->left = parent;
}
parent->parent = node;
node->parent = NULL;
} else {
- if(node == grandparent->left->left) { /* left zig-zig */
- grandparent->left = parent->right;
+ greatgrandparent = grandparent->parent;
+
+ if(node == parent->left && parent == grandparent->left) { /* left zig-zig */
+ if((grandparent->left = parent->right))
+ grandparent->left->parent = grandparent;
parent->right = grandparent;
grandparent->parent = parent;
- parent->left = node->right;
+ if((parent->left = node->right))
+ parent->left->parent = parent;
node->right = parent;
parent->parent = node;
-
- } else if(node == grandparent->right->right) { /* right zig-zig */
- grandparent->right = parent->left;
+ } else if(node == parent->right && parent == grandparent->right) { /* right zig-zig */
+ if((grandparent->right = parent->left))
+ grandparent->right->parent = grandparent;
parent->left = grandparent;
grandparent->parent = parent;
- parent->right = node->left;
+ if((parent->right = node->left))
+ parent->right->parent = parent;
node->left = parent;
parent->parent = node;
-
- } else if(node == grandparent->left->right) { /* left-right zig-zag */
- parent->right = node->left;
+ } else if(node == parent->right && parent == grandparent->left) { /* left-right zig-zag */
+ if((parent->right = node->left))
+ parent->right->parent = parent;
node->left = parent;
parent->parent = node;
- grandparent->left = node->right;
+ if((grandparent->left = node->right))
+ grandparent->left->parent = grandparent;
node->right = grandparent;
grandparent->parent = node;
-
} else { /* right-left zig-zag */
- parent->left = node->right;
+ if((parent->left = node->right))
+ parent->left->parent = parent;
node->right = parent;
parent->parent = node;
- grandparent->right = node->left;
+ if((grandparent->right = node->left))
+ grandparent->right->parent = grandparent;
node->left = grandparent;
grandparent->parent = node;
}
- node->parent = grandparent->parent;
-
- if(node->parent) {
- if(grandparent == node->parent->left)
- node->parent->left = node;
+ if((node->parent = greatgrandparent)) {
+ if(grandparent == greatgrandparent->left)
+ greatgrandparent->left = node;
else
- node->parent->right = node;
+ greatgrandparent->right = node;
}
}
}
if(c < 0) {
if(node->left)
node = node->left;
- else {
- if(result)
- *result = -1;
+ else
break;
- }
} else if(c > 0) {
if(node->right)
node = node->right;
- else {
- if(result)
- *result = 1;
+ else
break;
- }
} else {
- if(result)
- *result = 0;
break;
}
}
+ if(result)
+ *result = c;
return node;
}
new->data = data;
splay_insert_top(tree, new);
} else {
- closest = splay_search_closest_node_nosplay(tree, data, &result);
+ closest = splay_search_closest_node(tree, data, &result);
if(!result)
return NULL;
if(!tree->root)
splay_insert_top(tree, node);
else {
- closest = splay_search_closest_node_nosplay(tree, node->data, &result);
+ closest = splay_search_closest_node(tree, node->data, &result);
if(!result)
return NULL;
}
void splay_insert_top(splay_tree_t *tree, splay_node_t *node) {
- node->prev = node->next = node->parent = NULL;
+ node->prev = node->next = node->left = node->right = node->parent = NULL;
tree->head = tree->tail = tree->root = node;
}
}
node->next = before;
- node->parent = before;
- node->prev = before->prev;
-
- if(before->left) {
- splay_insert_after(tree, before->prev, node);
- return;
- }
-
- if(before->prev)
+ if((node->prev = before->prev))
before->prev->next = node;
else
tree->head = node;
-
before->prev = node;
- before->left = node;
- splay_bottom_up(tree, node);
+ splay_bottom_up(tree, before);
+
+ node->right = before;
+ before->parent = node;
+ if((node->left = before->left))
+ before->left->parent = node;
+ before->left = NULL;
+
+ node->parent = NULL;
+ tree->root = node;
}
void splay_insert_after(splay_tree_t *tree, splay_node_t *after, splay_node_t *node) {
return;
}
- if(after->right) {
- splay_insert_before(tree, after->next, node);
- return;
- }
-
node->prev = after;
- node->parent = after;
- node->next = after->next;
-
- if(after->next)
+ if((node->next = after->next))
after->next->prev = node;
else
tree->tail = node;
-
after->next = node;
- after->right = node;
- splay_bottom_up(tree, node);
+ splay_bottom_up(tree, after);
+
+ node->left = after;
+ after->parent = node;
+ if((node->right = after->right))
+ after->right->parent = node;
+ after->right = NULL;
+
+ node->parent = NULL;
+ tree->root = node;
}
splay_node_t *splay_unlink(splay_tree_t *tree, void *data) {
splay_node_t *node;
- int result;
- node = splay_search_closest_node_nosplay(tree, data, &result);
+ node = splay_search_node(tree, data);
- if(node && !result)
+ if(node)
splay_unlink_node(tree, node);
return node;
else
tree->tail = node->prev;
- if(node->left) {
+ splay_bottom_up(tree, node);
+
+ if(node->prev) {
node->left->parent = NULL;
tree->root = node->left;
-
- if(node->right) {
- splay_bottom_up(tree, node->prev);
- node->prev->right = node->right;
+ if((node->prev->right = node->right))
node->right->parent = node->prev;
- }
- } else {
- node->right->parent = NULL;
+ } else if(node->next) {
tree->root = node->right;
+ node->right->parent = NULL;
+ } else {
+ tree->root = NULL;
}
}
void splay_delete_tree(splay_tree_t *tree) {
splay_node_t *node, *next;
- for(node = tree->root; node; node = next) {
+ for(node = tree->head; node; node = next) {
next = node->next;
splay_free_node(tree, node);
}
projects / tinc / blobdiff