void *
avl_find (avl_tree *tree, const void *item)
{
const avl_node *p;
p = NULL;
assert (tree != NULL);
internal_lock_mutex(&tree->mutex);
for (p = tree->root.link[0]; p; )
{
int diff = tree->cmp (item, p->data, tree->param);
if (diff < 0)
p = p->link[0];
else if (diff > 0)
p = p->link[1];
else
{
internal_unlock_mutex(&tree->mutex);
return p->data;
}
}
internal_unlock_mutex(&tree->mutex);
return NULL;
}
void avl_destroy(avl_tree *tree, avl_node_func free_func)
{
assert(tree != NULL);
internal_lock_mutex(&tree->mutex);
#if PSPP
if (free_func || tree->owner == NULL)
#endif
{
avl_node *an[AVL_MAX_HEIGHT];
unsigned long ab = 0;
int ap = 0;
avl_node *p = tree->root.link[0];
for (;;)
{
/* T2. */
while (p != NULL)
{
/* T3. */
ab &= ~(1ul << ap);
an[ap++] = p;
p = p->link[0];
}
/* T4. */
for (;;)
{
if (ap == 0)
goto done;
p = an[--ap];
if ((ab & (1ul << ap)) == 0)
{
ab |= (1ul << ap++);
p = p->link[1];
break;
}
if (free_func)
free_func (p->data, tree->param);
#if PSPP
if (tree->owner == NULL)
#endif
free (p);
}
}
}
done:
internal_unlock_mutex(&tree->mutex);
thread_mutex_destroy(&tree->mutex);
#if PSPP
if (tree->owner == NULL)
#endif
free (tree);
}
void *
avl_traverse (avl_tree *tree, avl_traverser *trav)
{
assert (tree && trav);
internal_lock_mutex(&tree->mutex);
if (trav->init == 0)
{
trav->init = 1;
trav->nstack = 0;
trav->p = tree->root.link[0];
}
else
trav->p = trav->p->link[1];
for (;;)
{
while (trav->p != NULL)
{
trav->stack[trav->nstack++] = trav->p;
trav->p = trav->p->link[0];
}
if (trav->nstack == 0)
{
trav->init = 0;
internal_unlock_mutex(&tree->mutex);
return NULL;
}
trav->p = trav->stack[--trav->nstack];
internal_unlock_mutex(&tree->mutex);
return trav->p->data;
}
internal_unlock_mutex(&tree->mutex);
}
void
pool_unlock_write ()
{
assert (pool_mutex.thread_id != MUTEX_STATE_UNINIT);
internal_unlock_mutex (&pool_mutex);
}
void *
avl_delete (avl_tree *tree, const void *item)
{
avl_node *pa[AVL_MAX_HEIGHT];
char a[AVL_MAX_HEIGHT];
int k = 1;
avl_node **q;
avl_node *p;
assert (tree != NULL);
internal_lock_mutex(&tree->mutex);
a[0] = 0;
pa[0] = &tree->root;
p = tree->root.link[0];
for (;;)
{
int diff = tree->cmp (item, p->data, tree->param);
if (diff == 0)
break;
pa[k] = p;
if (diff < 0)
p = p->link[0], a[k] = 0;
else if (diff > 0)
p = p->link[1], a[k] = 1;
k++;
if (p == NULL)
{
internal_unlock_mutex(&tree->mutex);
return NULL;
}
}
tree->count--;
item = p->data;
q = &pa[k - 1]->link[(int) a[k - 1]];
if (p->link[1] == NULL)
{
*q = p->link[0];
if (*q)
(*q)->bal = 0;
}
else
{
avl_node *r = p->link[1];
if (r->link[0] == NULL)
{
r->link[0] = p->link[0];
*q = r;
r->bal = p->bal;
a[k] = 1;
pa[k++] = r;
}
else
{
avl_node *s = r->link[0];
int l = k++;
a[k] = 0;
pa[k++] = r;
while (s->link[0] != NULL)
{
r = s;
s = r->link[0];
a[k] = 0;
pa[k++] = r;
}
a[l] = 1;
pa[l] = s;
s->link[0] = p->link[0];
r->link[0] = s->link[1];
s->link[1] = p->link[1];
s->bal = p->bal;
*q = s;
}
}
#if PSPP
if (tree->owner == NULL)
#endif
free (p);
assert (k > 0);
while (--k)
{
avl_node *s = pa[k], *r;
if (a[k] == 0)
{
if (s->bal == -1)
{
s->bal = 0;
continue;
}
else if (s->bal == 0)
{
s->bal = 1;
break;
}
assert (s->bal == +1);
r = s->link[1];
assert (r != NULL);
if (r->bal == 0)
{
s->link[1] = r->link[0];
r->link[0] = s;
r->bal = -1;
pa[k - 1]->link[(int) a[k - 1]] = r;
break;
}
else if (r->bal == +1)
{
s->link[1] = r->link[0];
r->link[0] = s;
s->bal = r->bal = 0;
pa[k - 1]->link[(int) a[k - 1]] = r;
}
else
{
assert (r->bal == -1);
p = r->link[0];
r->link[0] = p->link[1];
p->link[1] = r;
s->link[1] = p->link[0];
p->link[0] = s;
if (p->bal == +1)
s->bal = -1, r->bal = 0;
else if (p->bal == 0)
s->bal = r->bal = 0;
else
{
assert (p->bal == -1);
s->bal = 0, r->bal = +1;
}
p->bal = 0;
pa[k - 1]->link[(int) a[k - 1]] = p;
}
}
else
{
assert (a[k] == 1);
if (s->bal == +1)
{
s->bal = 0;
continue;
}
else if (s->bal == 0)
{
s->bal = -1;
break;
}
assert (s->bal == -1);
r = s->link[0];
if (r == NULL || r->bal == 0)
{
s->link[0] = r->link[1];
r->link[1] = s;
r->bal = 1;
pa[k - 1]->link[(int) a[k - 1]] = r;
break;
}
else if (r->bal == -1)
{
s->link[0] = r->link[1];
r->link[1] = s;
s->bal = r->bal = 0;
pa[k - 1]->link[(int) a[k - 1]] = r;
}
else if (r->bal == +1)
{
p = r->link[1];
r->link[1] = p->link[0];
p->link[0] = r;
s->link[0] = p->link[1];
p->link[1] = s;
if (p->bal == -1)
s->bal = 1, r->bal = 0;
else if (p->bal == 0)
s->bal = r->bal = 0;
else
{
assert (p->bal == 1);
s->bal = 0, r->bal = -1;
}
p->bal = 0;
pa[k - 1]->link[(int) a[k - 1]] = p;
}
}
}
internal_unlock_mutex(&tree->mutex);
return (void *) item;
}