You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
69 lines
1.5 KiB
69 lines
1.5 KiB
|
|
#include "tst.h"
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <assert.h>
|
|
|
|
void *tst_search(unsigned char *key, struct tst *tst, int *prefix_len)
|
|
{
|
|
struct node *current_node;
|
|
void *longest_match = NULL;
|
|
int key_index;
|
|
|
|
assert(key != NULL && "key can't be NULL");
|
|
assert(tst != NULL && "tst can't be NULL");
|
|
|
|
if(key[0] == 0)
|
|
return NULL;
|
|
|
|
if(tst->head[(int)key[0]] == NULL)
|
|
return NULL;
|
|
|
|
|
|
if(prefix_len) *prefix_len = 0;
|
|
current_node = tst->head[(int)key[0]];
|
|
key_index = 1;
|
|
|
|
while (current_node != NULL)
|
|
{
|
|
if(key[key_index] == current_node->value)
|
|
{
|
|
if(current_node->value == 0) {
|
|
if(prefix_len) *prefix_len = key_index;
|
|
return current_node->middle;
|
|
} else {
|
|
current_node = current_node->middle;
|
|
if(current_node && current_node->value == 0) {
|
|
if(prefix_len) *prefix_len = key_index+1;
|
|
longest_match = current_node->middle;
|
|
}
|
|
|
|
key_index++;
|
|
continue;
|
|
}
|
|
}
|
|
else if( ((current_node->value == 0) && (key[key_index] < 64)) ||
|
|
((current_node->value != 0) && (key[key_index] <
|
|
current_node->value)) )
|
|
{
|
|
if(current_node->value == 0) {
|
|
if(prefix_len) *prefix_len = key_index;
|
|
longest_match = current_node->middle;
|
|
}
|
|
current_node = current_node->left;
|
|
continue;
|
|
}
|
|
else
|
|
{
|
|
if(current_node->value == 0) {
|
|
if(prefix_len) *prefix_len = key_index;
|
|
longest_match = current_node->middle;
|
|
}
|
|
current_node = current_node->right;
|
|
continue;
|
|
}
|
|
}
|
|
|
|
return longest_match;
|
|
}
|