linux核心源碼“雙向連結清單list_head”續

一、list.h頭檔案源碼

[root@bdkyr cstudy]# cat list.h             #list.h頭檔案

#ifndef _LINUX_LIST_H

#define _LINUX_LIST_H

#include

#undef offsetof

#ifdef __compiler_offsetof

#define offsetof(TYPE,MEMBER) __compiler_offsetof(TYPE,MEMBER)

#else

#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)

#endif

#define container_of(ptr, type, member) ({                      \

        const typeof( ((type *)0)->member ) *__mptr = (ptr);    \

        (type *)( (char *)__mptr - offsetof(type,member) );})

/*

 * Simple doubly linked list implementation.

 *

 * Some of the internal functions ("__xxx") are useful when

 * manipulating whole lists rather than single entries, as

 * sometimes we already know the next/prev entries and we can

 * generate better code by using them directly rather than

 * using the generic single-entry routines.

 */

struct list_head {

        struct list_head *next, *prev;

};

#define FLIST_HEAD_INIT(name) { &(name), &(name) }

#define FLIST_HEAD(name) \

        struct list_head name = FLIST_HEAD_INIT(name)

#define INIT_LIST_HEAD(ptr) do { \

        (ptr)->next = (ptr); (ptr)->prev = (ptr); \

} while (0)

 * Insert a new entry between two known consecutive entries.

 * This is only for internal list manipulation where we know

 * the prev/next entries already!

static inline void __list_add(struct list_head *new_entry,

                               struct list_head *prev,

                               struct list_head *next)

{

        next->prev = new_entry;

        new_entry->next = next;

        new_entry->prev = prev;

        prev->next = new_entry;

}

/**

 * list_add - add a new entry

 * @new_entry: new entry to be added

 * @head: list head to add it after

 * Insert a new entry after the specified head.

 * This is good for implementing stacks.

static inline void list_add(struct list_head *new_entry,

                             struct list_head *head)

        __list_add(new_entry, head, head->next);

static inline void list_add_tail(struct list_head *new_entry,

                                  struct list_head *head)

        __list_add(new_entry, head->prev, head);

 * Delete a list entry by making the prev/next entries

 * point to each other.

static inline void __list_del(struct list_head *prev,

                               struct list_head * next)

        next->prev = prev;

        prev->next = next;

 * list_del - deletes entry from list.

 * @entry: the element to delete from the list.

 * Note: list_empty on entry does not return true after this, the entry is

 * in an undefined state.

static inline void list_del(struct list_head *entry)

        __list_del(entry->prev, entry->next);

        entry->next = NULL;

        entry->prev = NULL;

 * list_del_init - deletes entry from list and reinitialize it.

static inline void list_del_init(struct list_head *entry)

        INIT_LIST_HEAD(entry);

 * 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;

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;

static inline void list_splice(const struct list_head *list,

                                struct list_head *head)

        if (!list_empty(list))

                __list_splice(list, head, head->next);

static inline void list_splice_init(struct list_head *list,

                                    struct list_head *head)

        if (!list_empty(list)) {

                INIT_LIST_HEAD(list);

        }

 * 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        -       iterate over a list

 * @pos:        the &struct list_head to use as a loop counter.

 * @head:       the head for your list.

#define list_for_each(pos, head) \

        for (pos = (head)->next; pos != (head); pos = pos->next)

 * list_for_each_safe   -       iterate over a list safe against removal of list entry

 * @n:          another &struct list_head to use as temporary storage

#define list_for_each_safe(pos, n, head) \

        for (pos = (head)->next, n = pos->next; pos != (head); \

                pos = n, n = pos->next)

extern void list_sort(void *priv, struct list_head *head,

        int (*cmp)(void *priv, struct list_head *a, struct list_head *b));

二、編譯double_list.c

[root@bdkyr cstudy]# gcc double_list.c -o double_list

三、運作

[root@bdkyr cstudy]# ./double_list                   

************周遊連結清單，列印結果**************

val = 1, num = 1

val = 2, num = 2

val = 3, num = 3

************删除節點b,重新周遊連結清單，列印結果*

************列印連結清單head1******************

val = 4, num = 4

val = 5, num = 5

*******************************************

the list is not empty!

如果博友覺得這個連結清單不錯，可以參考測試執行個體，編寫适合自己業務應用的代碼，謝謝！