/* lpm_init:
* Constructs a fresh tree ready for use by the other functions.
*/
struct lpm_tree* lpm_init()
{
/* Build empty internal node, and attach it to new tree. */
struct internal_node* node = create_internal_node();
struct lpm_tree* tree = (struct lpm_tree*)malloc(sizeof(struct lpm_tree));
DEBUG("## Created tree %p\n", (void*)tree);
tree->head = node;
return tree;
}
/*
* This function used internally; see lpm_insert().
*/
void insert(struct sockaddr_storage *prefix, uint32_t nm, struct internal_node* n)
{
uint8_t b = 0;
uint8_t depth = 0;
struct internal_node* parent;
struct internal_node* next = n;
if (prefix->ss_family == AF_INET6) {
b = MAX_BITS6;
}
else if (prefix->ss_family == AF_INET) {
b = MAX_BITS4;
}
/* First, find the correct location for the prefix. Burrow down to
the correct depth, potentially creating internal nodes as I
go. */
do {
n = next;
b--;
depth++;
parent = (struct internal_node*)n;
bool v_bit = test_v_bit(prefix, b);
/* Determine which direction to descend. */
if (v_bit) {
if (n->r == NULL) {
n->r = create_internal_node();
}
next = n->r;
}
else {
if (n->l == NULL) {
n->l = create_internal_node();
}
next = n->l;
}
} while (depth < nm);
if (next == NULL) {
/* The easy case. */
struct data_node* node = create_data_node(prefix, nm);
bool v_bit = test_v_bit(prefix, b);
if (v_bit) {
parent->r = (struct internal_node*)node;
}
else {
parent->l = (struct internal_node*)node;
}
}
else if (next->type == INT_NODE) {
/* In this case, we've descended as far as we can. Attach the
prefix here. */
bool v_bit = test_v_bit(prefix, b);
struct data_node* newnode = create_data_node(prefix, nm);
newnode->l = next->l;
newnode->r = next->r;
if (v_bit) {
n->r = (struct internal_node*)newnode;
}
else {
n->l = (struct internal_node*)newnode;
}
DEBUG("## Freeing %p\n", (void*)next);
free(next);
}
}
/*
* This function used internally; see lpm_insert().
*/
void insert(uint32_t prefix, uint32_t nm, struct internal_node* n, uint32_t network_owner)
{
uint8_t b = MAX_BITS;
uint8_t depth = 0;
struct internal_node* parent;
struct internal_node* next = n;
/* First, find the correct location for the prefix. Burrow down to
the correct depth, potentially creating internal nodes as I
go. */
do {
n = next;
b--;
depth++;
parent = (struct internal_node*)n;
uint32_t v_bit = prefix & ((uint32_t)pow(2, b));
/* Determine which direction to descend. */
if (v_bit) {
if (n->r == NULL) {
n->r = create_internal_node();
}
next = n->r;
}
else {
if (n->l == NULL) {
n->l = create_internal_node();
}
next = n->l;
}
} while (depth < nm);
if (next == NULL) {
/* The easy case. */
struct data_node* node = create_data_node(prefix, nm, network_owner);
uint32_t v_bit = prefix & ((uint32_t)pow(2, b));
if (v_bit) {
parent->r = (struct internal_node*)node;
}
else {
parent->l = (struct internal_node*)node;
}
}
else if (next->type == INT_NODE) {
/* In this case, we've descended as far as we can. Attach the
prefix here. */
uint32_t v_bit = prefix & ((uint32_t)pow(2, b));
struct data_node* newnode = create_data_node(prefix, nm, network_owner);
newnode->l = next->l;
newnode->r = next->r;
if (v_bit) {
n->r = (struct internal_node*)newnode;
}
else {
n->l = (struct internal_node*)newnode;
}
DEBUG("## Freeing %p\n", (void*)n);
free(next);
}
}
