This article will take you to understand the double-linked list in the Redis data structure, and briefly introduce the use of double-linked lists. I hope it will be helpful to everyone!
In the list list of the Redis data type, the commonly used commands for adding and deleting data are lpush, rpush, lpop, rpop, among which l It means on the left side, r means on the right side. You can add and delete operations on the left and right sides, indicating that this is a two-way data structure, and the list data structure is a doubly linked list, similar to the LinekdList in Java. [Related recommendations: Redis Video Tutorial]
The linked list provides efficient node rearrangement capabilities and sequential node access methods. The data of the linked list can be modified by modifying the pre and next pointers of the nodes. .
The C language does not have a built-in linked list data structure, so Redis builds its own linked list structure.
The linked list is composed of linked list and linked list nodes. Each linked list node is represented by a adlist.h/listNode structure :
typedef struct listNode { //前置节点 struct listNode *prev; //后置节点 struct listNode *next; // 节点值 void *value; } listNode;
Multiple listNodes can form a double linked list through prev and next pointers, as shown in the title:
##Multiple listNodes can form a linked list, but in order To facilitate management, useadlist.h/list to manage the linked list. The list structure is as follows:
typedef struct list { // 列表头结点 listNode *head; // 列表尾结构 listNode *tail; // 节点值复制函数 void *(*dup)(void *ptr); // 节点值释放函数 void (*free)(void *ptr); // 节点值对比函数 int (*match)(void *ptr, void *key); // 列表节点数量 unsigned long len; } list;
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