skiplist_node_t *pos_insert_skiplist(skiplist_t *sl, skiplist_node_t **ptr, skiplist_key_t *key, skiplist_data_t *data)
{
skiplist_node_t *sn2;
int level, i;
//** New node has to be inserted
level = get_random_level(sl->max_levels, sl->p, sl->current_max);
sn2 = create_skiplist_node(level);
log_printf(15, "insert_skiplist: new node. level=%d\n", level);
if (level > sl->current_max) { //** Need to adjust the head to handle the higher levels
for (i=sl->current_max+1; i<=level; i++) {
ptr[i] = sl->head;
}
sl->current_max = level;
}
for (i=0; i<=level; i++) {
sn2->next[i] = ptr[i]->next[i];
ptr[i]->next[i] = sn2;
}
//** Finally store the data
sn2->key = sl->dup(key);
sn2->ele.data = data;
return(sn2);
}
bool skip_list<T>::insert_node(int key, T value)
{
//find in every level in the past skip list
//which node is the last smaller than key
skip_node<T> *last_smaller_in_level[MAX_LEVEL];
skip_node<T> *tmp = header;
for(int i = 0; i <= level; i++)
{
while(tmp->next_in_level[i] != NULL)
{
if(tmp->next_in_level[i]->key == key)
{
printf("can't insert same key\n");
return false;
}
if(tmp->next_in_level[i]->key > key)
break;
else
tmp = tmp->next_in_level[i];
}
last_smaller_in_level[i] = tmp;
}
//random how much level to inserit
//build a new skip list
int insert_level = get_random_level();
printf("key %d insert_level %d\n", key, insert_level);
skip_node<T> *p = create_skip_node(key, value);
if(insert_level > level)
{
for(int i = 0; i <= level; i++)
{
skip_node<T> *tmp2 = last_smaller_in_level[i]->next_in_level[i];
last_smaller_in_level[i]->next_in_level[i] = p;
p->next_in_level[i] = tmp2;
}
for(int i = level + 1; i <= insert_level; i++)
{
header->next_in_level[i] = p;
}
level = insert_level;
}
else
{
for(int i = 0; i <= insert_level; i++)
{
skip_node<T> *tmp2 = last_smaller_in_level[i]->next_in_level[i];
last_smaller_in_level[i]->next_in_level[i] = p;
p->next_in_level[i] = tmp2;
}
}
return true;
}
static void insert_data_in_skiplist(
skiplist_struct *skiplist,
update_struct *update,
float key,
void *data_ptr )
{
int i, new_level;
skip_struct *x;
#ifdef DEBUG
int prev_size = -1;
void test_skiplist_integrity();
#endif
new_level = get_random_level();
if( new_level > skiplist->level )
{
for( i = skiplist->level; i < new_level; ++i )
update->update[i] = skiplist->header;
#ifdef DEBUG
prev_size = skiplist->level;
#endif
skiplist->level = new_level;
}
ALLOC_SKIP_STRUCT( x, new_level );
x->data_ptr = data_ptr;
x->key = key;
for( i = 0; i < new_level; ++i )
{
x->forward[i] = update->update[i]->forward[i];
update->update[i]->forward[i] = x;
}
#ifdef DEBUG
test_skiplist_integrity( skiplist );
#endif
}
static void insert_ptr_in_alloc_list(
alloc_struct *alloc_list,
update_struct *update,
void *ptr,
size_t n_bytes,
VIO_STR source_file,
int line_number,
int sequence_number )
{
int i, new_level;
skip_entry *x;
new_level = get_random_level();
if( new_level > alloc_list->level )
{
for( i = alloc_list->level; i < new_level; ++i )
update->update[i] = alloc_list->header;
alloc_list->level = new_level;
}
ALLOC_SKIP_STRUCT( x, new_level );
skip_alloc_size += sizeof(skip_entry)+((size_t)new_level-1) *
sizeof(skip_entry *);
x->ptr = ptr;
x->n_bytes = n_bytes;
x->source_file = source_file;
x->line_number = line_number;
x->sequence_number = sequence_number;
update_total_memory( alloc_list, n_bytes );
for( i = 0; i < new_level; ++i )
{
x->forward[i] = update->update[i]->forward[i];
update->update[i]->forward[i] = x;
}
}