This source file includes following definitions.
- ngx_radix_tree_create
- ngx_radix32tree_insert
- ngx_radix32tree_delete
- ngx_radix32tree_find
- ngx_radix128tree_insert
- ngx_radix128tree_delete
- ngx_radix128tree_find
- ngx_radix_alloc
#include <ngx_config.h>
#include <ngx_core.h>
static ngx_radix_node_t *ngx_radix_alloc(ngx_radix_tree_t *tree);
ngx_radix_tree_t *
ngx_radix_tree_create(ngx_pool_t *pool, ngx_int_t preallocate)
{
uint32_t key, mask, inc;
ngx_radix_tree_t *tree;
tree = ngx_palloc(pool, sizeof(ngx_radix_tree_t));
if (tree == NULL) {
return NULL;
}
tree->pool = pool;
tree->free = NULL;
tree->start = NULL;
tree->size = 0;
tree->root = ngx_radix_alloc(tree);
if (tree->root == NULL) {
return NULL;
}
tree->root->right = NULL;
tree->root->left = NULL;
tree->root->parent = NULL;
tree->root->value = NGX_RADIX_NO_VALUE;
if (preallocate == 0) {
return tree;
}
if (preallocate == -1) {
switch (ngx_pagesize / sizeof(ngx_radix_node_t)) {
case 128:
preallocate = 6;
break;
case 256:
preallocate = 7;
break;
default:
preallocate = 8;
}
}
mask = 0;
inc = 0x80000000;
while (preallocate--) {
key = 0;
mask >>= 1;
mask |= 0x80000000;
do {
if (ngx_radix32tree_insert(tree, key, mask, NGX_RADIX_NO_VALUE)
!= NGX_OK)
{
return NULL;
}
key += inc;
} while (key);
inc >>= 1;
}
return tree;
}
ngx_int_t
ngx_radix32tree_insert(ngx_radix_tree_t *tree, uint32_t key, uint32_t mask,
uintptr_t value)
{
uint32_t bit;
ngx_radix_node_t *node, *next;
bit = 0x80000000;
node = tree->root;
next = tree->root;
while (bit & mask) {
if (key & bit) {
next = node->right;
} else {
next = node->left;
}
if (next == NULL) {
break;
}
bit >>= 1;
node = next;
}
if (next) {
if (node->value != NGX_RADIX_NO_VALUE) {
return NGX_BUSY;
}
node->value = value;
return NGX_OK;
}
while (bit & mask) {
next = ngx_radix_alloc(tree);
if (next == NULL) {
return NGX_ERROR;
}
next->right = NULL;
next->left = NULL;
next->parent = node;
next->value = NGX_RADIX_NO_VALUE;
if (key & bit) {
node->right = next;
} else {
node->left = next;
}
bit >>= 1;
node = next;
}
node->value = value;
return NGX_OK;
}
ngx_int_t
ngx_radix32tree_delete(ngx_radix_tree_t *tree, uint32_t key, uint32_t mask)
{
uint32_t bit;
ngx_radix_node_t *node;
bit = 0x80000000;
node = tree->root;
while (node && (bit & mask)) {
if (key & bit) {
node = node->right;
} else {
node = node->left;
}
bit >>= 1;
}
if (node == NULL) {
return NGX_ERROR;
}
if (node->right || node->left) {
if (node->value != NGX_RADIX_NO_VALUE) {
node->value = NGX_RADIX_NO_VALUE;
return NGX_OK;
}
return NGX_ERROR;
}
for ( ;; ) {
if (node->parent->right == node) {
node->parent->right = NULL;
} else {
node->parent->left = NULL;
}
node->right = tree->free;
tree->free = node;
node = node->parent;
if (node->right || node->left) {
break;
}
if (node->value != NGX_RADIX_NO_VALUE) {
break;
}
if (node->parent == NULL) {
break;
}
}
return NGX_OK;
}
uintptr_t
ngx_radix32tree_find(ngx_radix_tree_t *tree, uint32_t key)
{
uint32_t bit;
uintptr_t value;
ngx_radix_node_t *node;
bit = 0x80000000;
value = NGX_RADIX_NO_VALUE;
node = tree->root;
while (node) {
if (node->value != NGX_RADIX_NO_VALUE) {
value = node->value;
}
if (key & bit) {
node = node->right;
} else {
node = node->left;
}
bit >>= 1;
}
return value;
}
#if (NGX_HAVE_INET6)
ngx_int_t
ngx_radix128tree_insert(ngx_radix_tree_t *tree, u_char *key, u_char *mask,
uintptr_t value)
{
u_char bit;
ngx_uint_t i;
ngx_radix_node_t *node, *next;
i = 0;
bit = 0x80;
node = tree->root;
next = tree->root;
while (bit & mask[i]) {
if (key[i] & bit) {
next = node->right;
} else {
next = node->left;
}
if (next == NULL) {
break;
}
bit >>= 1;
node = next;
if (bit == 0) {
if (++i == 16) {
break;
}
bit = 0x80;
}
}
if (next) {
if (node->value != NGX_RADIX_NO_VALUE) {
return NGX_BUSY;
}
node->value = value;
return NGX_OK;
}
while (bit & mask[i]) {
next = ngx_radix_alloc(tree);
if (next == NULL) {
return NGX_ERROR;
}
next->right = NULL;
next->left = NULL;
next->parent = node;
next->value = NGX_RADIX_NO_VALUE;
if (key[i] & bit) {
node->right = next;
} else {
node->left = next;
}
bit >>= 1;
node = next;
if (bit == 0) {
if (++i == 16) {
break;
}
bit = 0x80;
}
}
node->value = value;
return NGX_OK;
}
ngx_int_t
ngx_radix128tree_delete(ngx_radix_tree_t *tree, u_char *key, u_char *mask)
{
u_char bit;
ngx_uint_t i;
ngx_radix_node_t *node;
i = 0;
bit = 0x80;
node = tree->root;
while (node && (bit & mask[i])) {
if (key[i] & bit) {
node = node->right;
} else {
node = node->left;
}
bit >>= 1;
if (bit == 0) {
if (++i == 16) {
break;
}
bit = 0x80;
}
}
if (node == NULL) {
return NGX_ERROR;
}
if (node->right || node->left) {
if (node->value != NGX_RADIX_NO_VALUE) {
node->value = NGX_RADIX_NO_VALUE;
return NGX_OK;
}
return NGX_ERROR;
}
for ( ;; ) {
if (node->parent->right == node) {
node->parent->right = NULL;
} else {
node->parent->left = NULL;
}
node->right = tree->free;
tree->free = node;
node = node->parent;
if (node->right || node->left) {
break;
}
if (node->value != NGX_RADIX_NO_VALUE) {
break;
}
if (node->parent == NULL) {
break;
}
}
return NGX_OK;
}
uintptr_t
ngx_radix128tree_find(ngx_radix_tree_t *tree, u_char *key)
{
u_char bit;
uintptr_t value;
ngx_uint_t i;
ngx_radix_node_t *node;
i = 0;
bit = 0x80;
value = NGX_RADIX_NO_VALUE;
node = tree->root;
while (node) {
if (node->value != NGX_RADIX_NO_VALUE) {
value = node->value;
}
if (key[i] & bit) {
node = node->right;
} else {
node = node->left;
}
bit >>= 1;
if (bit == 0) {
i++;
bit = 0x80;
}
}
return value;
}
#endif
static ngx_radix_node_t *
ngx_radix_alloc(ngx_radix_tree_t *tree)
{
ngx_radix_node_t *p;
if (tree->free) {
p = tree->free;
tree->free = tree->free->right;
return p;
}
if (tree->size < sizeof(ngx_radix_node_t)) {
tree->start = ngx_pmemalign(tree->pool, ngx_pagesize, ngx_pagesize);
if (tree->start == NULL) {
return NULL;
}
tree->size = ngx_pagesize;
}
p = (ngx_radix_node_t *) tree->start;
tree->start += sizeof(ngx_radix_node_t);
tree->size -= sizeof(ngx_radix_node_t);
return p;
}