03dlist-kernel_list

最新推荐文章于 2023-02-08 18:11:51 发布

转载最新推荐文章于 2023-02-08 18:11:51 发布 · 500 阅读

数据结构与算法专栏收录该内容

26 篇文章

订阅专栏

本文详细介绍了链表数据结构的基础知识，包括链表节点定义、初始化、添加、删除节点等基本操作，以及如何实现链表的遍历，通过实例展示了链表在不同场景的应用。

list.h

struct list_head {
    struct list_head *prev;
    struct list_head *next;
};

#define LIST_HEAD(head) struct list_head head = {&head, &head}

static inline void INIT_LIST_HEAD(struct list_head *node)
{
    node->prev = node;
    node->next = node;
}

static inline void __list_add(struct list_head *node,
        struct list_head *prev,
        struct list_head *next)
{
    node->prev = prev;
    node->next = next;
    prev->next = node;
    next->prev = node;
}

static inline void list_add(struct list_head *node,
        struct list_head *head)
{
    __list_add(node, head, head->next);
}

static inline void list_add_tail(struct list_head *node,
        struct list_head *head)
{
    __list_add(node, head->prev, head);
}

static inline int list_emtpy(struct list_head *head)
{
    return head->next == head;
}

static inline void list_del(struct list_head *node)
{
    node->prev->next = node->next;
    node->next->prev = node->prev;
}

static inline void list_del_init(struct list_head *node)
{
    list_del(node);
    INIT_LIST_HEAD(node);
}

#define offsetof(type, member) \
    ((size_t)(&((type*)0)->member))

#define container_of(ptr, type, member) \
    ((type*)((char*)ptr - offsetof(type, member)))

/* @cur: ?..list_head?..?.复?舵.?
 * @head: 澶磋.?圭.?板.
 */
#define list_for_each(cur, head) \
    for (cur = (head)->next; \
        (cur) != (head); \
        cur = (cur)->next)

#define list_for_each_safe(cur, tmp, head) \
    for (cur = (head)->next, tmp = (cur)->next; \
        (cur) != (head); \
        cur = tmp, tmp = (tmp)->next)

#define list_for_each_entry(ptr, head, member) \
    for ( ptr = container_of((head)->next, typeof(*(ptr)), member); \
        &(ptr)->member != (head); \
        ptr = container_of((ptr)->member.next, typeof(*(ptr)), member) )

#define list_for_each_entry_safe(ptr, tmp, head, member) \
    for ( ptr = container_of((head)->next, typeof(*(ptr)), member); \
        (&(ptr)->member != (head)) && (tmp = container_of((ptr)->member.next, typeof(*(ptr)), member)); \
        ptr = tmp )

#define list_for_each_continue(cur, head) \
    for (cur = (cur)->next; \
        (cur) != (head); \
        cur = (cur)->next)

#define list_for_each_reverse(cur, head) \
    for (cur = (head)->prev; \
        (cur) != (head); \
        cur = (cur)->prev)

test.c

#include <stdio.h>
#include <string.h>
#include "list.h"

struct node {
    const char *name;
    size_t data;
    struct list_head list;
};

int main()
{
    LIST_HEAD(list);

    size_t i = 0;
    struct node s[] = { 
        {"jack", 10},
        {"mike", 20},
        {"mary", 12},
        {"tom", 15},
        {"peter", 17},
        {"kate", 18},
    };  

    for (i = 0; i < sizeof(s) / sizeof(struct node); i++) {
        list_add_tail(&s[i].list, &list);
    }

    struct list_head *cur = NULL;
    struct list_head *tmp = NULL;
    struct node *pnode = NULL;
    struct node *ptmp = NULL;

    list_for_each_entry(pnode, &list, list) {
        printf("%s: %ld\n", pnode->name, pnode->data);
    }   
    printf("\n");

/*        list_for_each_safe(cur, tmp, &list) {
 *                pnode = container_of(cur, struct node, list);
 *                if (!strcmp(pnode->name, "tom")) {
 *                        list_del_init(cur);
 *                }
 *        }*/
    list_for_each_entry_safe(pnode, ptmp, &list, list) {
        if (!strcmp(pnode->name, "mary")) {
            list_del_init(&pnode->list);
        }
    }

    list_for_each(cur, &list) {
        pnode = container_of(cur, struct node, list);
        printf("%s: %ld\n", pnode->name, pnode->data);
    }

return 0;

}