/* Delete the node z, and free up the space
*/
static void rb_delete(struct rbnode **rootp, struct rbnode *z) {
struct rbnode *x, *y, *tmp;
const void *max;
if (z->left == RBNULL || z->right == RBNULL)
y=z;
else
y=rb_successor(z);
if (y->left != RBNULL)
x=y->left;
else
x=y->right;
x->up = y->up;
if (y->up == RBNULL) {
*rootp=x;
} else {
if (y==y->up->left)
y->up->left = x;
else
y->up->right = x;
}
if (y!=z) {
z->key = y->key;
z->high=y->high;
z->object=y->object;
}
tmp=y->up;
while(tmp!=RBNULL) {
max=NULL;
if (tmp->left!=RBNULL)
max=tmp->left->max;
if (tmp->right!=RBNULL&&
tmp->right->max>max)
max=tmp->right->max;
if (tmp->high>max)
max=tmp->high;
tmp->max=max;
tmp=tmp->up;
}
if (y->colour == BLACK)
rb_delete_fix(rootp, x);
rb_free(y);
}
/* --------------------------------------
* brief : delete pdata from rb tree
* para t: rb tree pointer
* para pdata: data pointer
* return : success 0, failed -1
* -------------------------------------- */
int rb_delete(RBTree *t, void *pdata) {
if (t->rb_count == 0){
return -1;
}
RBNode *z = rb_find(t, pdata);
if (!z) return -1;
RBNode *y = z, *x = NULL;
RB_NODE_COLOR color = y->color;
if (z->child[0] == t->nil) {
x = z->child[1];
rb_trans(t, z, x);
}
else if (z->child[1] == t->nil) {
x = z->child[0];
rb_trans(t, z, x);
}
else {
y = rb_min(t, z->child[1]);
color = y->color;
x = y->child[1];
if (y->p == z) {
x->p = y;
}
else {
rb_trans(t, y, x);
y->child[1] = z->child[1];
y->child[1]->p = y;
}
rb_trans(t, z, y);
y->child[0] = z->child[0];
y->child[0]->p = y;
y->color = z->color;
}
//free(z);
//z = NULL;
((RBLANode*)z)->next = t->p;
t->p = (RBLANode*)z;
if (color == RB_BLACK) {
rb_delete_fix(t, x);
}
t->rb_count -= 1;
return 0;
}