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-rw-r--r--app/nginx/src/core/ngx_rbtree.c409
1 files changed, 0 insertions, 409 deletions
diff --git a/app/nginx/src/core/ngx_rbtree.c b/app/nginx/src/core/ngx_rbtree.c
deleted file mode 100644
index 969d549..0000000
--- a/app/nginx/src/core/ngx_rbtree.c
+++ /dev/null
@@ -1,409 +0,0 @@
-
-/*
- * Copyright (C) Igor Sysoev
- * Copyright (C) Nginx, Inc.
- */
-
-
-#include <ngx_config.h>
-#include <ngx_core.h>
-
-
-/*
- * The red-black tree code is based on the algorithm described in
- * the "Introduction to Algorithms" by Cormen, Leiserson and Rivest.
- */
-
-
-static ngx_inline void ngx_rbtree_left_rotate(ngx_rbtree_node_t **root,
- ngx_rbtree_node_t *sentinel, ngx_rbtree_node_t *node);
-static ngx_inline void ngx_rbtree_right_rotate(ngx_rbtree_node_t **root,
- ngx_rbtree_node_t *sentinel, ngx_rbtree_node_t *node);
-
-
-void
-ngx_rbtree_insert(ngx_rbtree_t *tree, ngx_rbtree_node_t *node)
-{
- ngx_rbtree_node_t **root, *temp, *sentinel;
-
- /* a binary tree insert */
-
- root = &tree->root;
- sentinel = tree->sentinel;
-
- if (*root == sentinel) {
- node->parent = NULL;
- node->left = sentinel;
- node->right = sentinel;
- ngx_rbt_black(node);
- *root = node;
-
- return;
- }
-
- tree->insert(*root, node, sentinel);
-
- /* re-balance tree */
-
- while (node != *root && ngx_rbt_is_red(node->parent)) {
-
- if (node->parent == node->parent->parent->left) {
- temp = node->parent->parent->right;
-
- if (ngx_rbt_is_red(temp)) {
- ngx_rbt_black(node->parent);
- ngx_rbt_black(temp);
- ngx_rbt_red(node->parent->parent);
- node = node->parent->parent;
-
- } else {
- if (node == node->parent->right) {
- node = node->parent;
- ngx_rbtree_left_rotate(root, sentinel, node);
- }
-
- ngx_rbt_black(node->parent);
- ngx_rbt_red(node->parent->parent);
- ngx_rbtree_right_rotate(root, sentinel, node->parent->parent);
- }
-
- } else {
- temp = node->parent->parent->left;
-
- if (ngx_rbt_is_red(temp)) {
- ngx_rbt_black(node->parent);
- ngx_rbt_black(temp);
- ngx_rbt_red(node->parent->parent);
- node = node->parent->parent;
-
- } else {
- if (node == node->parent->left) {
- node = node->parent;
- ngx_rbtree_right_rotate(root, sentinel, node);
- }
-
- ngx_rbt_black(node->parent);
- ngx_rbt_red(node->parent->parent);
- ngx_rbtree_left_rotate(root, sentinel, node->parent->parent);
- }
- }
- }
-
- ngx_rbt_black(*root);
-}
-
-
-void
-ngx_rbtree_insert_value(ngx_rbtree_node_t *temp, ngx_rbtree_node_t *node,
- ngx_rbtree_node_t *sentinel)
-{
- ngx_rbtree_node_t **p;
-
- for ( ;; ) {
-
- p = (node->key < temp->key) ? &temp->left : &temp->right;
-
- if (*p == sentinel) {
- break;
- }
-
- temp = *p;
- }
-
- *p = node;
- node->parent = temp;
- node->left = sentinel;
- node->right = sentinel;
- ngx_rbt_red(node);
-}
-
-
-void
-ngx_rbtree_insert_timer_value(ngx_rbtree_node_t *temp, ngx_rbtree_node_t *node,
- ngx_rbtree_node_t *sentinel)
-{
- ngx_rbtree_node_t **p;
-
- for ( ;; ) {
-
- /*
- * Timer values
- * 1) are spread in small range, usually several minutes,
- * 2) and overflow each 49 days, if milliseconds are stored in 32 bits.
- * The comparison takes into account that overflow.
- */
-
- /* node->key < temp->key */
-
- p = ((ngx_rbtree_key_int_t) (node->key - temp->key) < 0)
- ? &temp->left : &temp->right;
-
- if (*p == sentinel) {
- break;
- }
-
- temp = *p;
- }
-
- *p = node;
- node->parent = temp;
- node->left = sentinel;
- node->right = sentinel;
- ngx_rbt_red(node);
-}
-
-
-void
-ngx_rbtree_delete(ngx_rbtree_t *tree, ngx_rbtree_node_t *node)
-{
- ngx_uint_t red;
- ngx_rbtree_node_t **root, *sentinel, *subst, *temp, *w;
-
- /* a binary tree delete */
-
- root = &tree->root;
- sentinel = tree->sentinel;
-
- if (node->left == sentinel) {
- temp = node->right;
- subst = node;
-
- } else if (node->right == sentinel) {
- temp = node->left;
- subst = node;
-
- } else {
- subst = ngx_rbtree_min(node->right, sentinel);
-
- if (subst->left != sentinel) {
- temp = subst->left;
- } else {
- temp = subst->right;
- }
- }
-
- if (subst == *root) {
- *root = temp;
- ngx_rbt_black(temp);
-
- /* DEBUG stuff */
- node->left = NULL;
- node->right = NULL;
- node->parent = NULL;
- node->key = 0;
-
- return;
- }
-
- red = ngx_rbt_is_red(subst);
-
- if (subst == subst->parent->left) {
- subst->parent->left = temp;
-
- } else {
- subst->parent->right = temp;
- }
-
- if (subst == node) {
-
- temp->parent = subst->parent;
-
- } else {
-
- if (subst->parent == node) {
- temp->parent = subst;
-
- } else {
- temp->parent = subst->parent;
- }
-
- subst->left = node->left;
- subst->right = node->right;
- subst->parent = node->parent;
- ngx_rbt_copy_color(subst, node);
-
- if (node == *root) {
- *root = subst;
-
- } else {
- if (node == node->parent->left) {
- node->parent->left = subst;
- } else {
- node->parent->right = subst;
- }
- }
-
- if (subst->left != sentinel) {
- subst->left->parent = subst;
- }
-
- if (subst->right != sentinel) {
- subst->right->parent = subst;
- }
- }
-
- /* DEBUG stuff */
- node->left = NULL;
- node->right = NULL;
- node->parent = NULL;
- node->key = 0;
-
- if (red) {
- return;
- }
-
- /* a delete fixup */
-
- while (temp != *root && ngx_rbt_is_black(temp)) {
-
- if (temp == temp->parent->left) {
- w = temp->parent->right;
-
- if (ngx_rbt_is_red(w)) {
- ngx_rbt_black(w);
- ngx_rbt_red(temp->parent);
- ngx_rbtree_left_rotate(root, sentinel, temp->parent);
- w = temp->parent->right;
- }
-
- if (ngx_rbt_is_black(w->left) && ngx_rbt_is_black(w->right)) {
- ngx_rbt_red(w);
- temp = temp->parent;
-
- } else {
- if (ngx_rbt_is_black(w->right)) {
- ngx_rbt_black(w->left);
- ngx_rbt_red(w);
- ngx_rbtree_right_rotate(root, sentinel, w);
- w = temp->parent->right;
- }
-
- ngx_rbt_copy_color(w, temp->parent);
- ngx_rbt_black(temp->parent);
- ngx_rbt_black(w->right);
- ngx_rbtree_left_rotate(root, sentinel, temp->parent);
- temp = *root;
- }
-
- } else {
- w = temp->parent->left;
-
- if (ngx_rbt_is_red(w)) {
- ngx_rbt_black(w);
- ngx_rbt_red(temp->parent);
- ngx_rbtree_right_rotate(root, sentinel, temp->parent);
- w = temp->parent->left;
- }
-
- if (ngx_rbt_is_black(w->left) && ngx_rbt_is_black(w->right)) {
- ngx_rbt_red(w);
- temp = temp->parent;
-
- } else {
- if (ngx_rbt_is_black(w->left)) {
- ngx_rbt_black(w->right);
- ngx_rbt_red(w);
- ngx_rbtree_left_rotate(root, sentinel, w);
- w = temp->parent->left;
- }
-
- ngx_rbt_copy_color(w, temp->parent);
- ngx_rbt_black(temp->parent);
- ngx_rbt_black(w->left);
- ngx_rbtree_right_rotate(root, sentinel, temp->parent);
- temp = *root;
- }
- }
- }
-
- ngx_rbt_black(temp);
-}
-
-
-static ngx_inline void
-ngx_rbtree_left_rotate(ngx_rbtree_node_t **root, ngx_rbtree_node_t *sentinel,
- ngx_rbtree_node_t *node)
-{
- ngx_rbtree_node_t *temp;
-
- temp = node->right;
- node->right = temp->left;
-
- if (temp->left != sentinel) {
- temp->left->parent = node;
- }
-
- temp->parent = node->parent;
-
- if (node == *root) {
- *root = temp;
-
- } else if (node == node->parent->left) {
- node->parent->left = temp;
-
- } else {
- node->parent->right = temp;
- }
-
- temp->left = node;
- node->parent = temp;
-}
-
-
-static ngx_inline void
-ngx_rbtree_right_rotate(ngx_rbtree_node_t **root, ngx_rbtree_node_t *sentinel,
- ngx_rbtree_node_t *node)
-{
- ngx_rbtree_node_t *temp;
-
- temp = node->left;
- node->left = temp->right;
-
- if (temp->right != sentinel) {
- temp->right->parent = node;
- }
-
- temp->parent = node->parent;
-
- if (node == *root) {
- *root = temp;
-
- } else if (node == node->parent->right) {
- node->parent->right = temp;
-
- } else {
- node->parent->left = temp;
- }
-
- temp->right = node;
- node->parent = temp;
-}
-
-
-ngx_rbtree_node_t *
-ngx_rbtree_next(ngx_rbtree_t *tree, ngx_rbtree_node_t *node)
-{
- ngx_rbtree_node_t *root, *sentinel, *parent;
-
- sentinel = tree->sentinel;
-
- if (node->right != sentinel) {
- return ngx_rbtree_min(node->right, sentinel);
- }
-
- root = tree->root;
-
- for ( ;; ) {
- parent = node->parent;
-
- if (node == root) {
- return NULL;
- }
-
- if (node == parent->left) {
- return parent;
- }
-
- node = parent;
- }
-}