/* Inserts a new node (leaf or internal node) into the B+ tree.
* Returns the root of the tree after insertion.
*/
node * insert_into_parent(node * root, node * left, int key, node * right) {
int left_index;
node * parent;
parent = left->parent;
/* Case: new root. */
if (parent == NULL)
return insert_into_new_root(left, key, right);
/* Case: leaf or node. (Remainder of
* function body.)
*/
/* Find the parent's pointer to the left
* node.
*/
left_index = get_left_index(parent, left);
/* Simple case: the new key fits into the node.
*/
if (parent->num_keys < order - 1)
return insert_into_node(root, parent, left_index, key, right);
/* Harder case: split a node in order
* to preserve the B+ tree properties.
*/
return insert_into_node_after_splitting(root, parent, left_index, key, right);
}
node *insert_into_parent(node *root, node *left, node *right, char *key)
{
node *parent;
int index, i;
parent = left->parent;
if (parent == NULL){
return make_new_root(left, right, key);
}
for (index = 0; index < parent->num_keys && parent->pointers[index] != left; index++);
;
if (parent->num_keys < size - 1){
insert_into_node(parent, right, index, key);
return root; // the root remains unchanged
}
return insert_into_node_after_splitting(root, parent, right, index, key);
}
