linux 内核链表练习

        linux 内核链表使用案例：

链表源码：test_list.c

/********************************************** * Author: [e-mail] * File name: test_list.c * Description: test the macroes in the core.h  * Date: 2011-12-14 *********************************************/#include <stdlib.h>#include <stdio.h>#include <malloc.h>#include "list.h"#define MAX_LEN20struct student{    char name[MAX_LEN];    unsigned long long id;    struct list_head ls_stu;};static struct list_head stu_list;static struct student *id_stu(unsigned long *id_no){    return (container_of(id_no, struct student, id));}static void stu_init(struct student **stu){*stu = (struct student *)malloc(sizeof(struct student));INIT_LIST_HEAD(&(*stu)->ls_stu); }static void list_print(){struct student *pos;if (list_empty(&stu_list)) {printf("stu_list is NULL!\n");return ;}list_for_each_entry(pos, &stu_list, ls_stu) {printf("Name:%s, id:%lu;\n", pos->name, pos->id);}    printf("-------------------------------\n");}int main(int argc, char *argv[]){    unsigned long offset;    char *name_fst = "aaaa";    char *name_sec = "bbbb";    char *name_tmp = "zzzz";    struct student *stu_fst, *stu_sec, *stu_tmp;INIT_LIST_HEAD(&stu_list); /* 全局链表初始化 */if (list_empty(&stu_list)) /* 判断链表是否为NULL */printf("stu_list is NULL\n");/* 初始化3个stu实例，用于链表操作练习 */stu_init(&stu_fst);memcpy(stu_fst->name, name_fst, strlen(name_fst));stu_fst->id = 2004035001;stu_init(&stu_sec);memcpy(stu_sec->name, name_sec, strlen(name_sec));stu_sec->id = 2004035002;stu_init(&stu_tmp);memcpy(stu_tmp->name, name_tmp, strlen(name_tmp));stu_tmp->id = 2004035000;/* 将stu_sec->ls_stu添加到链表stu_list */printf("Insert entry:2004035002.\n");list_add(&stu_sec->ls_stu, &stu_list); list_print();/* 将stu_fst->ls_stu添加到链表stu_list */printf("Insert entry in the front of stu_list: 2004035001.\n");list_add(&stu_fst->ls_stu, &stu_list); list_print();/* 将stu_tmp->ls_stu添加到链表stu_list */printf("Insert entry in the front of stu_list: 2004035000.\n");list_add_tail(&stu_tmp->ls_stu, &stu_list); list_print();/* 将stu_tmp->ls_stu从链表stu_list中删除 */printf("Delete entry : 2004035000.\n");list_del(&stu_tmp->ls_stu); list_print();    return 0;}

输出结果：

[root@RedHat list_sample]# ./mainstu_list is NULLInsert entry:2004035002.Name:bbbb, id:2004035002;-------------------------------Insert entry in the front of stu_list: 2004035001.Name:aaaa, id:2004035001;Name:bbbb, id:2004035002;-------------------------------Insert entry in the front of stu_list: 2004035000.Name:aaaa, id:2004035001;Name:bbbb, id:2004035002;Name:zzzz, id:2004035000;-------------------------------Delete entry : 2004035000.Name:aaaa, id:2004035001;Name:bbbb, id:2004035002;-------------------------------[root@RedHat list_sample]#

链表源码：list.h 原来摘自内核（3.1.6版本）

/********************************************** * Author: [e-mail] * File name: list.h * Description: define some macroes * Date: 2011-12-29 *********************************************/#ifndef __CORE_H#define __CORE_H//typedef unsigned long size_t;#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)#define container_of(ptr, type, member) ({          \        const typeof( ((type *)0)->member ) *__mptr = (ptr);    \        (type *)( (char *)__mptr - offsetof(type,member) );})/* list struct */struct list_head {        struct list_head *next, *prev;};/* list initialization */static inline void INIT_LIST_HEAD(struct list_head *list){    list->next = list;    list->prev = list;}/** * list_empty - tests whether a list is empty * @head: the list to test. */static inline int list_empty(const struct list_head *head){return head->next == head;}/* Insert a new entry between two known consecutive entries */static inline void __list_add(struct list_head *new,                          struct list_head *prev, struct list_head *next){    next->prev = new;    new->next = next;    new->prev = prev;    prev->next = new;}/* add a new entry in the front of head */static inline void list_add(struct list_head *new, struct list_head *head){    __list_add(new, head, head->next);}/* insert a new entry in the end of head */static inline void list_add_tail(struct list_head *new, struct list_head *head){        __list_add(new, head->prev, head);}/* deletes entry from list */static inline void __list_del(struct list_head *prev, struct list_head *next){next->prev = prev;prev->next = next;}/* deletes entry from list */static inline void list_del(struct list_head *entry){__list_del(entry->prev, entry->next);entry->next = (void *)0xDEADBEEF;entry->prev = (void *)0xBEEFDEAD;}/* replace old entry by new one */static inline void list_replace(struct list_head *old, struct list_head *new){new->next = old->next;new->next->prev = new;new->prev = old->prev;new->prev->next = new;}/*  * delete from one list and add as another's head * @list: the entry to move * @head: the head that will precede our entry */static inline void list_move(struct list_head *list, struct list_head *head){__list_del(list->prev, list->next);list_add(list, head);}/** * list_move_tail - delete from one list and add as another's tail * @list: the entry to move * @head: the head that will follow our entry */static inline void list_move_tail(struct list_head *list,  struct list_head *head){__list_del(list->prev, list->next);list_add_tail(list, head);}static inline void __list_splice(const struct list_head *list, struct list_head *prev, struct list_head *next){struct list_head *first = list->next;struct list_head *last = list->prev;first->prev = prev;prev->next = first;last->next = next;next->prev = last;}/** * list_splice - join two lists, this is designed for stacks * @list: the new list to add. * @head: the place to add it in the first list. */static inline void list_splice(const struct list_head *list,       struct list_head *head){if (!list_empty(list))__list_splice(list, head, head->next);}/** * list_entry - get the struct for this entry * @ptr:the &struct list_head pointer. * @type:the type of the struct this is embedded in. * @member:the name of the list_struct within the struct. */#define list_entry(ptr, type, member) \container_of(ptr, type, member)/** * list_for_each_entry-iterate over list of given type * @pos:the type * to use as a loop cursor. * @head:the head for your list. * @member:the name of the list_struct within the struct. */#define list_for_each_entry(pos, head, member)\for (pos = list_entry((head)->next, typeof(*pos), member);\     &pos->member != (head); \     pos = list_entry(pos->member.next, typeof(*pos), member))#endif