static int insert_ptr(NODE **rootaddr,
NODE *node, int (*usrcmp)(void *, void *), int dup)
{
NODE *root = *rootaddr;
int cmp;
int ins;
SET_PTRCMP(cmp, usrcmp, node->key.ptr, root->key.ptr)
if (cmp < 0) {
if (root->left)
ins = insert_ptr(&root->left, node, usrcmp, dup);
else {
root->left = node;
ins = DEEPER;
}
switch (ins) {
CASE DEEPER : switch (root->bal)
{
CASE RIGHT : root->bal = BAL;
return INS;
CASE BAL : root->bal = LEFT;
return DEEPER;
CASE LEFT : root->bal = LEFTUNBAL;
return rebalance(rootaddr) == LESS ? INS : DEEPER;
}
CASE INS : return INS;
CASE NOTINS : return NOTINS;
}
} else if (cmp > 0 || dup) {
int MUTABOR_CLASS_FUNCTION(ptrlist,insert)(void * _self,const void * ptr)
{
MUT_CLASS(ptrlist) *self=_self;
if (!self->root) {
self->root=calloc(sizeof(struct mutabor_avl_node_ptr),1);
self->root->data=ptr;
return 1;
}
return insert_ptr(&self->root,ptr);
}
static void move_item(struct btree_page *from, int from_pos,
struct btree_page *to, int to_pos)
{
if (from->height)
insert_ptr(to, to_pos, PAGE_KEY(from, from_pos),
*PAGE_PTR(from, from_pos));
else
insert_data(to, to_pos, PAGE_KEY(from, from_pos),
PAGE_DATA(from, from_pos));
delete_item(from, from_pos);
}
void
objc_hashtable_set_ptr(struct objc_hashtable *h, const void *key, const void *obj)
{
int64_t idx = index_for_key_ptr(h, key);
if (idx < 0) {
insert_ptr(h, key, obj);
return;
}
h->data[idx]->obj = obj;
}
switch (ins) {
CASE DEEPER : switch (root->bal)
{
CASE RIGHT : root->bal = BAL;
return INS;
CASE BAL : root->bal = LEFT;
return DEEPER;
CASE LEFT : root->bal = LEFTUNBAL;
return rebalance(rootaddr) == LESS ? INS : DEEPER;
}
CASE INS : return INS;
CASE NOTINS : return NOTINS;
}
} else if (cmp > 0 || dup) {
if (root->right)
ins = insert_ptr(&root->right, node, usrcmp, dup);
else {
root->right = node;
ins = DEEPER;
}
switch (ins) {
CASE DEEPER : switch (root->bal)
{
CASE LEFT : root->bal = BAL;
return INS;
CASE BAL : root->bal = RIGHT;
return DEEPER;
CASE RIGHT : root->bal = RIGHTUNBAL;
return rebalance(rootaddr) == LESS ? INS : DEEPER;
}
CASE INS : return INS;
int btree_put(btree_t bt, const void *key, const void *data)
{
const struct btree_def *def = bt->def;
struct btree_page *new_root = NULL;
struct btree_page *path_new[MAX_HEIGHT] = {0};
struct btree_page *path_old[MAX_HEIGHT] = {0};
int slot_old[MAX_HEIGHT] = {0};
int h;
check_btree(bt);
/* Special case: cursor overwrite */
if (!key) {
if (bt->slot[0] < 0) {
fprintf(stderr, "btree: put at invalid cursor\n");
return -1;
}
memcpy(PAGE_DATA(bt->path[0], bt->slot[0]), data,
def->data_size);
return 1;
}
/* Find a path down the tree that leads to the page which should
* contain this datum (though the page might be too big to hold it).
*/
if (trace_path(bt, key, path_old, slot_old)) {
/* Special case: overwrite existing item */
memcpy(PAGE_DATA(path_old[0], slot_old[0]), data,
def->data_size);
return 1;
}
/* Trace from the leaf up. If the leaf is at its maximum size, it will
* need to split, and cause a pointer to be added in the parent page
* of the same node (which may in turn cause it to split).
*/
for (h = 0; h <= bt->root->height; h++) {
if (path_old[h]->num_children < def->branches)
break;
path_new[h] = allocate_page(bt, h);
if (!path_new[h])
goto fail;
}
/* If the split reaches the top (i.e. the root splits), then we need
* to allocate a new root node.
*/
if (h > bt->root->height) {
if (h >= MAX_HEIGHT) {
fprintf(stderr, "btree: maximum height exceeded\n");
goto fail;
}
new_root = allocate_page(bt, h);
if (!new_root)
goto fail;
}
/* Trace up to one page above the split. At each page that needs
* splitting, copy the top half of keys into the new page. Also,
* insert a key into one of the pages at all pages from the leaf
* to the page above the top of the split.
*/
for (h = 0; h <= bt->root->height; h++) {
int s = slot_old[h] + 1;
struct btree_page *p = path_old[h];
/* If there's a split at this level, copy the top half of
* the keys from the old page to the new one. Check to see
* if the position we were going to insert into is in the
* old page or the new one.
*/
if (path_new[h]) {
split_page(path_old[h], path_new[h]);
if (s > p->num_children) {
s -= p->num_children;
p = path_new[h];
}
}
/* Insert the key in the appropriate page */
if (h)
insert_ptr(p, s, PAGE_KEY(path_new[h - 1], 0),
path_new[h - 1]);
else
insert_data(p, s, key, data);
/* If there was no split at this level, there's nothing to
* insert higher up, and we're all done.
*/
if (!path_new[h])
return 0;
}
/* If we made it this far, the split reached the top of the tree, and
* we need to grow it using the extra page we allocated.
*/
assert (new_root);
if (bt->slot[0] >= 0) {
/* Fix up the cursor, if active */
bt->slot[new_root->height] =
bt->path[bt->root->height] == new_root ? 1 : 0;
bt->path[new_root->height] = new_root;
}
memcpy(PAGE_KEY(new_root, 0), def->zero, def->key_size);
*PAGE_PTR(new_root, 0) = path_old[h - 1];
memcpy(PAGE_KEY(new_root, 1), PAGE_KEY(path_new[h - 1], 0),
def->key_size);
*PAGE_PTR(new_root, 1) = path_new[h - 1];
new_root->num_children = 2;
bt->root = new_root;
return 0;
fail:
for (h = 0; h <= bt->root->height; h++)
if (path_new[h])
free(path_new[h]);
return -1;
}
