static struct rb_node *
rb_next_preorder_(struct rb_node *rbn, int *black_depth)
{
if (rbn->c[0]) {
if (!rb_is_red(rbn->c[0]))
*black_depth++;
return rbn->c[0];
} else if (rbn->c[1]) {
if (!rb_is_red(rbn->c[1]))
*black_depth++;
return rbn->c[1];
} else {
int l = *black_depth;
/* go up to the next right child we missed */
for (;;) {
if (!rb_is_red(rbn))
l--;
struct rb_node *p = rb_parent(rbn);
if (!p) {
*black_depth = l;
return NULL;
}
if (p->c[1]) {
if (!rb_is_red(p->c[1]))
*black_depth = l;
return p->c[1];
}
}
}
}
void rb_insert_color(struct rb_node *node, struct rb_root *root)
{
struct rb_node *parent, *gparent;
while((parent = rb_parent(node)) && rb_is_red(parent)) {
gparent = rb_parent(parent);
if(parent == gparent->rb_left) {
{
register struct rb_node *uncle = gparent->rb_right;
if(uncle && rb_is_red(uncle)) {
rb_set_black(uncle);
rb_set_black(parent);
rb_set_red(gparent);
node = gparent;
continue;
}
}
if(parent->rb_right == node) {
register struct rb_node *tmp;
__rb_rotate_left(parent, root);
tmp = parent;
parent = node;
node = tmp;
}
rb_set_black(parent);
rb_set_red(gparent);
__rb_rotate_right(gparent, root);
} else {
{
register struct rb_node *uncle = gparent->rb_left;
if(uncle && rb_is_red(uncle)) {
rb_set_black(uncle);
rb_set_black(parent);
rb_set_red(gparent);
node = gparent;
continue;
}
}
if(parent->rb_left == node) {
register struct rb_node *tmp;
__rb_rotate_right(parent, root);
tmp = parent;
parent = node;
node = tmp;
}
rb_set_black(parent);
rb_set_red(gparent);
__rb_rotate_left(gparent, root);
}
}
rb_set_black(root->rb_node);
}
size_t rb_check_subtree(NodeTy* node, NodeTy** list)
{
size_t ret = 0;
if (node)
{
if (rb_is_red(node))
{
if (*list == nullptr)
{
throw ::std::runtime_error("root is red");
}
if (rb_is_red(*list))
{
throw ::std::runtime_error("two red node");
}
}
else
{
++ret;
}
*++list = node;
const size_t left = rb_check_subtree<NodeTy>(node->rb_left, list);
const size_t right = rb_check_subtree<NodeTy>(node->rb_right, list);
if (left != right)
{
throw ::std::runtime_error("number of black nodes does not match");
}
ret += left;
return ret;
}
return 0;
}
static noinline bool dump_tree_aux(struct rb_node *node, struct rb_node *parent,
int depth, char lr)
{
struct afs_vnode *vnode;
bool bad = false;
if (!node)
return false;
if (node->rb_left)
bad = dump_tree_aux(node->rb_left, node, depth + 2, '/');
vnode = rb_entry(node, struct afs_vnode, cb_promise);
_debug("%c %*.*s%c%p {%d}",
rb_is_red(node) ? 'R' : 'B',
depth, depth, "", lr,
vnode, vnode->cb_expires_at);
if (rb_parent(node) != parent) {
;
bad = true;
}
if (node->rb_right)
bad |= dump_tree_aux(node->rb_right, node, depth + 2, '\\');
return bad;
}
/*
* 打印"红黑树"
*
* tree -- 红黑树的节点
* key -- 节点的键值
* direction -- 0，表示该节点是根节点;
* -1，表示该节点是它的父结点的左孩子;
* 1，表示该节点是它的父结点的右孩子。
*/
static void rbtree_print(RBTree tree, Type key, int direction)
{
if(tree != NULL)
{
if(direction==0) // tree是根节点
printf("%2d(B) is root\n", tree->key);
else // tree是分支节点
printf("%2d(%s) is %2d's %6s child\n", tree->key, rb_is_red(tree)?"R":"B", key, direction==1?"right" : "left");
rbtree_print(tree->left, tree->key, -1);
rbtree_print(tree->right,tree->key, 1);
}
}
static void __rb_erase_color(LPRB_NODE node, LPRB_NODE parent, LPRB_ROOT root)
{
LPRB_NODE other;
while ((!node || rb_is_black(node)) && node != root->rb_node)
{
if (parent->rb_left == node)
{
other = parent->rb_right;
if (rb_is_red(other))
{
rb_set_black(other);
rb_set_red(parent);
__rb_rotate_left(parent, root);
other = parent->rb_right;
}
if ((!other->rb_left || rb_is_black(other->rb_left)) &&
(!other->rb_right || rb_is_black(other->rb_right)))
{
rb_set_red(other);
node = parent;
parent = rb_parent(node);
}
else
{
if (!other->rb_right || rb_is_black(other->rb_right))
{
rb_set_black(other->rb_left);
rb_set_red(other);
__rb_rotate_right(other, root);
other = parent->rb_right;
}
rb_set_color(other, rb_color(parent));
rb_set_black(parent);
rb_set_black(other->rb_right);
__rb_rotate_left(parent, root);
node = root->rb_node;
break;
}
}
else
{
other = parent->rb_left;
if (rb_is_red(other))
{
rb_set_black(other);
rb_set_red(parent);
__rb_rotate_right(parent, root);
other = parent->rb_left;
}
if ((!other->rb_left || rb_is_black(other->rb_left)) &&
(!other->rb_right || rb_is_black(other->rb_right)))
{
rb_set_red(other);
node = parent;
parent = rb_parent(node);
}
else
{
if (!other->rb_left || rb_is_black(other->rb_left))
{
rb_set_black(other->rb_right);
rb_set_red(other);
__rb_rotate_left(other, root);
other = parent->rb_left;
}
rb_set_color(other, rb_color(parent));
rb_set_black(parent);
rb_set_black(other->rb_left);
__rb_rotate_right(parent, root);
node = root->rb_node;
break;
}
}
}
if (node)
rb_set_black(node);
}
void rb_insert_color(LPRB_NODE node, LPRB_ROOT root)
{
LPRB_NODE parent, gparent;
while ((parent = rb_parent(node)) && rb_is_red(parent))
{
gparent = rb_parent(parent);
if (parent == gparent->rb_left)
{
{
register LPRB_NODE uncle = gparent->rb_right;
if (uncle && rb_is_red(uncle))
{
rb_set_black(uncle);
rb_set_black(parent);
rb_set_red(gparent);
node = gparent;
continue;
}
}
if (parent->rb_right == node)
{
register LPRB_NODE tmp;
__rb_rotate_left(parent, root);
tmp = parent;
parent = node;
node = tmp;
}
rb_set_black(parent);
rb_set_red(gparent);
__rb_rotate_right(gparent, root);
} else {
{
register LPRB_NODE uncle = gparent->rb_left;
if (uncle && rb_is_red(uncle))
{
rb_set_black(uncle);
rb_set_black(parent);
rb_set_red(gparent);
node = gparent;
continue;
}
}
if (parent->rb_left == node)
{
register LPRB_NODE tmp;
__rb_rotate_right(parent, root);
tmp = parent;
parent = node;
node = tmp;
}
rb_set_black(parent);
rb_set_red(gparent);
__rb_rotate_left(gparent, root);
}
}
rb_set_black(root->rb_node);
}
static void __rb_erase_color(struct rb_node *node, struct rb_node *parent,
struct rb_root *root)
{
struct rb_node *other;
while ((!node || rb_is_black(node)) && node != root->rb_node)
{
if (parent->rb_left == node)
{
other = parent->rb_right;
if (rb_is_red(other))
{
rb_set_black(other);
rb_set_red(parent);
__rb_rotate_left(parent, root);
other = parent->rb_right;
}
if ((!other->rb_left || rb_is_black(other->rb_left)) &&
(!other->rb_right || rb_is_black(other->rb_right)))
{
rb_set_red(other);
node = parent;
parent = rb_parent(node);
}
else
{
if (!other->rb_right || rb_is_black(other->rb_right))
{
struct rb_node *o_left;
if ((o_left = other->rb_left))
rb_set_black(o_left);
rb_set_red(other);
__rb_rotate_right(other, root);
other = parent->rb_right;
}
rb_set_color(other, rb_color(parent));
rb_set_black(parent);
if (other->rb_right)
rb_set_black(other->rb_right);
__rb_rotate_left(parent, root);
node = root->rb_node;
break;
}
}
else
{
other = parent->rb_left;
if (rb_is_red(other))
{
rb_set_black(other);
rb_set_red(parent);
__rb_rotate_right(parent, root);
other = parent->rb_left;
}
if ((!other->rb_left || rb_is_black(other->rb_left)) &&
(!other->rb_right || rb_is_black(other->rb_right)))
{
rb_set_red(other);
node = parent;
parent = rb_parent(node);
}
else
{
if (!other->rb_left || rb_is_black(other->rb_left))
{
register struct rb_node *o_right;
if ((o_right = other->rb_right))
rb_set_black(o_right);
rb_set_red(other);
__rb_rotate_left(other, root);
other = parent->rb_left;
}
rb_set_color(other, rb_color(parent));
rb_set_black(parent);
if (other->rb_left)
rb_set_black(other->rb_left);
__rb_rotate_right(parent, root);
node = root->rb_node;
break;
}
}
}
if (node)
rb_set_black(node);
}
void rb_insert_color(struct rb_node *node, struct rb_root *root)
{
struct rb_node *parent, *gparent;
struct mytype *mytype;
int pr_flag = 1;
mytype = container_of(node, struct mytype, node);
while ((parent = rb_parent(node)) && rb_is_red(parent))
{
gparent = rb_parent(parent);
if (parent == gparent->rb_left)
{
{
register struct rb_node *uncle = gparent->rb_right;
if (uncle && rb_is_red(uncle))
{
if (pr_flag)
{
pr_debug("insert value = %02d, 对应情况1。\n", mytype->keyvalue);
pr_flag = 0;
}
rb_set_black(uncle);
rb_set_black(parent);
rb_set_red(gparent);
node = gparent;
continue;
}
}
if (parent->rb_right == node)
{
if (pr_flag)
{
pr_debug("insert value = %02d, 对应情况2。\n", mytype->keyvalue);
pr_flag = 0;
}
register struct rb_node *tmp;
__rb_rotate_left(parent, root);
tmp = parent;
parent = node;
node = tmp;
}
if (pr_flag)
{
pr_debug("insert value = %02d, 对应情况3。\n", mytype->keyvalue);
pr_flag = 0;
}
rb_set_black(parent);
rb_set_red(gparent);
__rb_rotate_right(gparent, root);
} else {
{
register struct rb_node *uncle = gparent->rb_left;
if (uncle && rb_is_red(uncle))
{
if (pr_flag)
{
pr_debug("insert value = %02d, 对应情况1(反)。\n", mytype->keyvalue);
pr_flag = 0;
}
rb_set_black(uncle);
rb_set_black(parent);
rb_set_red(gparent);
node = gparent;
continue;
}
}
if (parent->rb_left == node)
{
if (pr_flag)
{
pr_debug("insert value = %02d, 对应情况2(反)。\n", mytype->keyvalue);
pr_flag = 0;
}
register struct rb_node *tmp;
__rb_rotate_right(parent, root);
tmp = parent;
parent = node;
node = tmp;
}
if (pr_flag)
{
pr_debug("insert value = %02d, 对应情况3(反)。\n", mytype->keyvalue);
pr_flag = 0;
}
rb_set_black(parent);
rb_set_red(gparent);
__rb_rotate_left(gparent, root);
}
}
if (pr_flag)
pr_debug("insert value = %02d, 对应情况X。\n", mytype->keyvalue);
rb_set_black(root->rb_node);
}
static void __rb_erase_color(struct rb_node *node, struct rb_node *parent,
struct rb_root *root)
{
struct rb_node *other;
int pr_flag = 1;
while ((!node || rb_is_black(node)) && node != root->rb_node)
{
if (parent->rb_left == node)
{
other = parent->rb_right;
if (rb_is_red(other))
{
if (pr_flag)
{
pr_debug("对应情况1。\n");
pr_flag = 0;
}
rb_set_black(other);
rb_set_red(parent);
__rb_rotate_left(parent, root);
other = parent->rb_right;
}
if ((!other->rb_left || rb_is_black(other->rb_left)) &&
(!other->rb_right || rb_is_black(other->rb_right)))
{
if (pr_flag)
{
pr_debug("对应情况2。\n");
pr_flag = 0;
}
rb_set_red(other);
node = parent;
parent = rb_parent(node);
}
else
{
if (!other->rb_right || rb_is_black(other->rb_right))
{
if (pr_flag)
{
pr_debug("对应情况3。\n");
pr_flag = 0;
}
rb_set_black(other->rb_left);
rb_set_red(other);
__rb_rotate_right(other, root);
other = parent->rb_right;
}
if (pr_flag)
{
pr_debug("对应情况4。\n");
pr_flag = 0;
}
rb_set_color(other, rb_color(parent));
rb_set_black(parent);
rb_set_black(other->rb_right);
__rb_rotate_left(parent, root);
node = root->rb_node;
break;
}
}
else
{
other = parent->rb_left;
if (rb_is_red(other))
{
if (pr_flag)
{
pr_debug("对应情况1(反)。\n");
pr_flag = 0;
}
rb_set_black(other);
rb_set_red(parent);
__rb_rotate_right(parent, root);
other = parent->rb_left;
}
if ((!other->rb_left || rb_is_black(other->rb_left)) &&
(!other->rb_right || rb_is_black(other->rb_right)))
{
if (pr_flag)
{
pr_debug("对应情况2(反)。\n");
pr_flag = 0;
}
rb_set_red(other);
node = parent;
parent = rb_parent(node);
}
else
{
if (!other->rb_left || rb_is_black(other->rb_left))
{
if (pr_flag)
{
pr_debug("对应情况3(反)。\n");
pr_flag = 0;
}
rb_set_black(other->rb_right);
rb_set_red(other);
__rb_rotate_left(other, root);
other = parent->rb_left;
}
if (pr_flag)
{
pr_debug("对应情况4(反)。\n");
pr_flag = 0;
}
rb_set_color(other, rb_color(parent));
rb_set_black(parent);
rb_set_black(other->rb_left);
__rb_rotate_right(parent, root);
node = root->rb_node;
break;
}
}
}
if (pr_flag)
{
if (node && rb_is_red(node)) //红结点
{
pr_debug("对应情况S。\n");
}
else
{
pr_debug("对应情况?。\n");
}
}
if (node)
rb_set_black(node);
}
static void rbtree_remove(char *node, char **tree)
{
char *parent = rb_get_parent(node);
char *left = rbtree_get_left(node);
char *right = rbtree_get_right(node);
char *next;
int color;
if (!left)
next = right;
else if (!right)
next = left;
else
next = rbtree_first(right);
if (parent)
rb_set_child(next, parent, rbtree_get_left(parent) == node);
else
*tree = next;
if (left && right) {
color = rb_get_color(next);
rb_set_color(rb_get_color(node), next);
rb_set_left(left, next);
rb_set_parent(next, left);
if (next != right) {
parent = rb_get_parent(next);
rb_set_parent(rb_get_parent(node), next);
node = rbtree_get_right(next);
rb_set_left(node, parent);
rb_set_right(right, next);
rb_set_parent(next, right);
} else {
rb_set_parent(parent, next);
parent = next;
node = rbtree_get_right(next);
}
} else {
color = rb_get_color(node);
node = next;
}
/*
* 'node' is now the sole successor's child and 'parent' its
* new parent (since the successor can have been moved).
*/
if (node)
rb_set_parent(parent, node);
/*
* The 'easy' cases.
*/
if (color == RB_RED)
return;
if (node && rb_is_red(node)) {
rb_set_color(RB_BLACK, node);
return;
}
do {
if (node == *tree)
break;
if (node == rbtree_get_left(parent)) {
char *sibling = rbtree_get_right(parent);
if (rb_is_red(sibling)) {
rb_set_color(RB_BLACK, sibling);
rb_set_color(RB_RED, parent);
rb_rotate_left(parent, tree);
sibling = rbtree_get_right(parent);
}
if ((!rbtree_get_left(sibling) || rb_is_black(rbtree_get_left(sibling))) &&
(!rbtree_get_right(sibling) || rb_is_black(rbtree_get_right(sibling)))) {
rb_set_color(RB_RED, sibling);
node = parent;
parent = rb_get_parent(parent);
continue;
}
if (!rbtree_get_right(sibling) || rb_is_black(rbtree_get_right(sibling))) {
rb_set_color(RB_BLACK, rbtree_get_left(sibling));
rb_set_color(RB_RED, sibling);
rb_rotate_right(sibling, tree);
sibling = rbtree_get_right(parent);
}
rb_set_color(rb_get_color(parent), sibling);
rb_set_color(RB_BLACK, parent);
rb_set_color(RB_BLACK, rbtree_get_right(sibling));
rb_rotate_left(parent, tree);
node = *tree;
break;
} else {
char *sibling = rbtree_get_left(parent);
if (rb_is_red(sibling)) {
rb_set_color(RB_BLACK, sibling);
rb_set_color(RB_RED, parent);
rb_rotate_right(parent, tree);
sibling = rbtree_get_left(parent);
}
if ((!rbtree_get_left(sibling) || rb_is_black(rbtree_get_left(sibling))) &&
(!rbtree_get_right(sibling) || rb_is_black(rbtree_get_right(sibling)))) {
rb_set_color(RB_RED, sibling);
node = parent;
parent = rb_get_parent(parent);
continue;
}
if (!rbtree_get_left(sibling) || rb_is_black(rbtree_get_left(sibling))) {
rb_set_color(RB_BLACK, rbtree_get_right(sibling));
rb_set_color(RB_RED, sibling);
rb_rotate_left(sibling, tree);
sibling = rbtree_get_left(parent);
}
rb_set_color(rb_get_color(parent), sibling);
rb_set_color(RB_BLACK, parent);
rb_set_color(RB_BLACK, rbtree_get_left(sibling));
rb_rotate_right(parent, tree);
node = *tree;
break;
}
} while (rb_is_black(node));
if (node)
rb_set_color(RB_BLACK, node);
}
static char *rbtree_insert(char *node, char **tree)
{
char *key, *parent;
int is_left;
key = rb_do_lookup(node, *tree, &parent, &is_left);
if (key)
return key;
rb_set_left(NULL, node);
rb_set_right(NULL, node);
rb_set_color(RB_RED, node);
rb_set_parent(parent, node);
if (parent) {
rb_set_child(node, parent, is_left);
} else {
*tree = node;
}
/*
* Fixup the modified tree by recoloring nodes and performing
* rotations (2 at most) hence the red-black tree properties are
* preserved.
*/
while ((parent = rb_get_parent(node)) && rb_is_red(parent)) {
char *grandpa = rb_get_parent(parent);
if (parent == rbtree_get_left(grandpa)) {
char *uncle = rbtree_get_right(grandpa);
if (uncle && rb_is_red(uncle)) {
rb_set_color(RB_BLACK, parent);
rb_set_color(RB_BLACK, uncle);
rb_set_color(RB_RED, grandpa);
node = grandpa;
} else {
if (node == rbtree_get_right(parent)) {
rb_rotate_left(parent, tree);
node = parent;
parent = rb_get_parent(node);
}
rb_set_color(RB_BLACK, parent);
rb_set_color(RB_RED, grandpa);
rb_rotate_right(grandpa, tree);
}
} else {
char *uncle = rbtree_get_left(grandpa);
if (uncle && rb_is_red(uncle)) {
rb_set_color(RB_BLACK, parent);
rb_set_color(RB_BLACK, uncle);
rb_set_color(RB_RED, grandpa);
node = grandpa;
} else {
if (node == rbtree_get_left(parent)) {
rb_rotate_right(parent, tree);
node = parent;
parent = rb_get_parent(node);
}
rb_set_color(RB_BLACK, parent);
rb_set_color(RB_RED, grandpa);
rb_rotate_left(grandpa, tree);
}
}
}
rb_set_color(RB_BLACK, *tree);
return NULL;
}
void rb_insert_rebalance(struct rb_node* node, struct rb_root* root)
{
struct rb_node *parent, *gparent, *uncle;
while ((parent = rb_parent(node)) && rb_is_red(parent)) {
gparent = rb_parent(parent);
if (parent == gparent->left) {
uncle = gparent->right;
if (uncle && rb_is_red(uncle)) {
rb_set_black(uncle);
rb_set_black(parent);
rb_set_red(gparent);
node = gparent;
continue;
}
if (node == parent->right) {
register struct rb_node* tmp;
rb_rotate_left(parent, root);
tmp = node;
node = parent;
parent = tmp;
}
rb_rotate_right(gparent, root);
rb_set_black(parent);
rb_set_red(gparent);
continue;
}
uncle = gparent->left;
if (uncle && rb_is_red(uncle)) {
rb_set_black(parent);
rb_set_black(uncle);
rb_set_red(gparent);
node = gparent;
continue;
}
if (node == parent->left) {
register struct rb_node* tmp;
rb_rotate_right(parent, root);
tmp = node;
node = parent;
parent = tmp;
}
rb_rotate_left(gparent, root);
rb_set_red(gparent);
rb_set_black(parent);
}
rb_set_black(root->node);
}
static inline void rb_delete_rebalance(struct rb_node* node,
struct rb_node* parent,
struct rb_root* root)
{
struct rb_node* sibling;
while ((!node || rb_is_black(node)) && (node != root->node)) {
if (node == parent->left) {
sibling = parent->right;
if (rb_is_red(sibling)) {
rb_rotate_left(parent, root);
rb_set_red(parent);
rb_set_black(sibling);
sibling = parent->right;
}
if ((!sibling->left || rb_is_black(sibling->left)) &&
(!sibling->right || rb_is_black(sibling->right))) {
rb_set_red(sibling);
node = parent;
/* if (node) */ parent = rb_parent(node);
} else {
if (!sibling->right || rb_is_black(sibling->right)) {
rb_set_black(sibling->left);
rb_set_red(sibling);
rb_rotate_right(sibling, root);
sibling = parent->right;
}
rb_set_color(sibling, rb_color(parent));
rb_set_black(parent);
rb_set_black(sibling->right);
rb_rotate_left(parent, root);
node = root->node;
break;
}
} else {
sibling = parent->left;
if (rb_is_red(sibling)) {
rb_rotate_right(parent, root);
rb_set_red(parent);
rb_set_black(sibling);
sibling = parent->left;
}
if ((!sibling->left || rb_is_black(sibling->left)) &&
(!sibling->right || rb_is_black(sibling->right))) {
rb_set_red(sibling);
node = parent;
/* if (node) */ parent = rb_parent(node);
} else {
if (!sibling->left || rb_is_black(sibling->left)) {
rb_set_black(sibling->right);
rb_set_red(sibling);
rb_rotate_left(sibling, root);
sibling = parent->left;
}
rb_set_color(sibling, rb_color(parent));
rb_set_black(parent);
rb_set_black(sibling->left);
rb_rotate_right(parent, root);
node = root->node;
break;
}
}
}
if (node)
rb_set_black(node);
}
/*
* 红黑树删除修正函数
*
* 在从红黑树中删除插入节点之后(红黑树失去平衡)，再调用该函数；
* 目的是将它重新塑造成一颗红黑树。
*
* 参数说明：
* root 红黑树的根
* node 待修正的节点
*/
static void rbtree_delete_fixup(RBRoot *root, Node *node, Node *parent)
{
Node *other;
while ((!node || rb_is_black(node)) && node != root->node)
{
if (parent->left == node)
{
//1. parent parent.r old.ohter.b
// / \ / \ / \
// child.b other.r child.b other.b parent.r d
// / \ / \ / \ / \ / \
// a b c d a b c d child.b c <- new.other
// / \
// a b
other = parent->right;
if (rb_is_red(other))
{
// Case 1: x的兄弟w是红色的
rb_set_black(other);
rb_set_red(parent);
rbtree_left_rotate(root, parent);
other = parent->right;
}
//2. gparent gparent 3. <- new.parent
// |
// parent parent 2. <- new.child
// / \ / \
// child.b other old.child.b other.r 1. <- color = RED
// / \ / \
// a b c.b d.b
if ((!other->left || rb_is_black(other->left)) &&
(!other->right || rb_is_black(other->right)))
{
// Case 2: x的兄弟w是黑色，且w的俩个孩子也都是黑色的
rb_set_red(other);
node = parent;
parent = rb_parent(node);
}
else
{
if (!other->right || rb_is_black(other->right))
{
//3.1 parent parent parent
// / \ / \ / \
// child.b other.b child.b other.r <- color RED child.b c.b <- new.other
// / \ / \ / \ / \ / \ \
// a b c d.b a b c.b d.b <- c.color BLACK a b old.other.r
// / \
// d.b
// Case 3: x的兄弟w是黑色的，并且w的左孩子是红色，右孩子为黑色。
rb_set_black(other->left);
rb_set_red(other);
rbtree_right_rotate(root, other);
other = parent->right;
}
//3.2 parent.c parent.b 2<- color BLACK other.b
// / \ / \ / \
// child.b other.b child.b other.c 1<- color parent.color parent.b d.b
// / \ / \ / \ / \ / \
// a b c d.r a b c d.b 3<- color BLACK child.b c
// / \
// a b
// Case 4: x的兄弟w是黑色的；并且w的右孩子是红色的，左孩子任意颜色。
rb_set_color(other, rb_color(parent));
rb_set_black(parent);
rb_set_black(other->right);
rbtree_left_rotate(root, parent);
node = root->node;
break;
}
}
else
{
other = parent->left;
if (rb_is_red(other))
{
// Case 1: x的兄弟w是红色的
rb_set_black(other);
rb_set_red(parent);
rbtree_right_rotate(root, parent);
other = parent->left;
}
if ((!other->left || rb_is_black(other->left)) &&
(!other->right || rb_is_black(other->right)))
{
// Case 2: x的兄弟w是黑色，且w的俩个孩子也都是黑色的
rb_set_red(other);
node = parent;
parent = rb_parent(node);
}
else
{
if (!other->left || rb_is_black(other->left))
{
// Case 3: x的兄弟w是黑色的，并且w的左孩子是红色，右孩子为黑色。
rb_set_black(other->right);
rb_set_red(other);
rbtree_left_rotate(root, other);
other = parent->left;
}
// Case 4: x的兄弟w是黑色的；并且w的右孩子是红色的，左孩子任意颜色。
rb_set_color(other, rb_color(parent));
rb_set_black(parent);
rb_set_black(other->left);
rbtree_right_rotate(root, parent);
node = root->node;
break;
}
}
}
if (node)
rb_set_black(node);
}
/*
* 红黑树插入修正函数
*
* 在向红黑树中插入节点之后(失去平衡)，再调用该函数；
* 目的是将它重新塑造成一颗红黑树。
*
* 参数说明：
* root 红黑树的根
* node 插入的结点 // 对应《算法导论》中的z
*/
static void rbtree_insert_fixup(RBRoot *root, Node *node)
{
Node *parent, *gparent;
// 若“父节点存在，并且父节点的颜色是红色”
while ((parent = rb_parent(node)) && rb_is_red(parent))
{
gparent = rb_parent(parent);
//若“父节点”是“祖父节点的左孩子”
if (parent == gparent->left)
{
// Case 1条件：叔叔节点是红色
{
Node *uncle = gparent->right;
if (uncle && rb_is_red(uncle))
{
rb_set_black(uncle);
rb_set_black(parent);
rb_set_red(gparent);
node = gparent;
continue;
}
}
// Case 2条件：叔叔是黑色，且当前节点是右孩子
if (parent->right == node)
{
Node *tmp;
rbtree_left_rotate(root, parent);
tmp = parent;
parent = node;
node = tmp;
}
// Case 3条件：叔叔是黑色，且当前节点是左孩子。
rb_set_black(parent);
rb_set_red(gparent);
rbtree_right_rotate(root, gparent);
}
else//若“z的父节点”是“z的祖父节点的右孩子”
{
// Case 1条件：叔叔节点是红色
{
Node *uncle = gparent->left;
if (uncle && rb_is_red(uncle))
{
rb_set_black(uncle);
rb_set_black(parent);
rb_set_red(gparent);
node = gparent;
continue;
}
}
// Case 2条件：叔叔是黑色，且当前节点是左孩子
if (parent->left == node)
{
Node *tmp;
rbtree_right_rotate(root, parent);
tmp = parent;
parent = node;
node = tmp;
}
// Case 3条件：叔叔是黑色，且当前节点是右孩子。
rb_set_black(parent);
rb_set_red(gparent);
rbtree_left_rotate(root, gparent);
}
}
// 将根节点设为黑色
rb_set_black(root->node);
}