Linux内核之旅 链表实现

 #include "stdio.h"
 #include "stdlib.h"

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

 struct task{
     int member;
     struct list_head list;
 };

 #define list_entry(ptr,member,type) \
 ((type*)((char *)ptr-(unsigned long)&(((type*))->member)))

 #define Init_list(list) {&list,&list}

  static  void list_add(struct list_head* ptr,struct list_head* n){
     ptr->next=n->next;
     n->next->prev=ptr;
     n->next=ptr;
     ptr->prev=n;
 }

 #define for_each(list_)\
 for(pos=list_.next;pos!=&list_;pos=pos->next)\
 {printf("%d ",list_entry(pos,list,struct task)->member);}\
 printf("\n");

 void main(){
     struct task* tmp;
     int i;
     struct list_head mylist=Init_list(mylist),*pos;

     for( i=;i<;i++){
         tmp=(struct task*)malloc(sizeof(struct task));
         scanf("%d",&(tmp->member));
         list_add(&(tmp->list),&mylist);
     }

     for_each(mylist);

 }