/**
 * container_of - cast a member of a structure out to the containing structure
 * @ptr:	the pointer to the member.结构体的成员变量的指针。
 * @type:	the type of the container struct this is embedded in.结构体类型。
 * @member:	the name of the member within the struct.ptr对应的成员变量在结构体中的名称。
 *
 */
#define container_of(ptr, type, member) ({			\
	const typeof( ((type *)0)->member ) *__mptr = (ptr);	\
	(type *)( (char *)__mptr - offsetof(type,member) );})

typedef int key_t;      //key类型
typedef int data_t;     //数据类型
typedef enum color_t{   //rb数color
    RED = 0,
    BLACK = 1
} color_t;

//节点定义
typedef struct rb_node_t{
    struct rb_node_t *left, *right, *parent; //三个指针
    key_t key;      //key
    data_t data;    //value
    color_t color;  //locor
} rb_node_t;
//文件中包含了函数：
//函数声明：
static rb_node_t* rb_new_node(key_t key, data_t data);                 //新建节点
static rb_node_t* rb_rotate_left(rb_node_t* node, rb_node_t* root);    //左旋
static rb_node_t* rb_rotate_right(rb_node_t* node, rb_node_t* root);   //右旋
static rb_node_t* rb_search_parent(key_t key, rb_node_t* root, rb_node_t **parent);    //协助搜索节点
rb_node_t* rb_search(key_t key, rb_node_t* root);               //搜索节点
rb_node_t* rb_insert(key_t key, data_t data, rb_node_t* root);  //插入节点
static rb_node_t* rb_insert_fixup(rb_node_t *node, rb_node_t *root);   //插入节点后修正
rb_node_t* rb_erase(key_t key, rb_node_t *root);                //删除节点
static rb_node_t* rb_erase_fixup(rb_node_t *child, rb_node_t *parent, rb_node_t *root);//删除节点后修正