C宏里面代码什么意思（附代码）

题目

C宏里面代码什么意思（附代码）
//安全遍历
#define list_for_each_safe(cur,tmp,list)
for (cur = (list)->head.next,
tmp = (cur)->next;
cur = &(list)->head;
cur = tmp,tmp = (tmp)->next)
list_for_each_safe(cur,tmp,dlist) {
dlist->del(cur);
}
为什么宏里面的方法重写了,

答案

#define list_for_each_safe(cur, tmp, list) for (cur = (list)->head.next, tmp = (cur)->next; cur != &(list)->head; cur = tmp, tmp = (tmp)->next)上面这些是宏代码,下面这些是调用这个宏.list_for...