linux 的3个不同的队列接口

linux自带的三种 queue接口: Lists/Tail queues/Circular queues的使用. 
每一个接口宏(非函数)都用了至少一次.

0. 环境
   Distributor ID: Ubuntu
    Description: Ubuntu 14.04.1 LTS
    Release: 14.04
    Codename: trusty
1. 代码及运行
    a. list接口代码list.c
    

#include    <stdio.h>
#include    <stdlib.h>
#include    <sys/queue.h>

LIST_HEAD(listhead, entry) head;
struct listhead *headp; /* List head. */
struct entry {
    int value;
    LIST_ENTRY(entry) entries; /* List. */
} *n1, *n2, *np;

int main(int argc, char *argv[])
{
    int i = 0;
    LIST_INIT(&head); /* Initialize the list. */

    n1 = malloc(sizeof(struct entry)); /* Insert at the head. */
    n1->value = 10000;
    LIST_INSERT_HEAD(&head, n1, entries);

    for(i = 0; i < 10; i++)
    {
        n2 = malloc(sizeof(struct entry)); /* Insert after. */
        n2->value = i;
        LIST_INSERT_AFTER(n1, n2, entries);
    }
    /* Forward traversal. */
    for (np = head.lh_first; np != NULL; np = np->entries.le_next)
    printf("value is %d\n", np->value);

    while (head.lh_first != NULL) /* Delete. */
    {
        LIST_REMOVE(head.lh_first, entries);
    }
    return  0;
}

编译/运行后结果如下:

代码简短.不解释

-------------------------------------------------
 b. TailQueue接口代码TailQueue.c

#include    <stdio.h>
#include    <stdlib.h>
#include    <sys/queue.h>

TAILQ_HEAD(tailhead, entry) head;
struct tailhead *headp; /* Tail queue head. */
struct entry {
    int value;
    TAILQ_ENTRY(entry) entries; /* Tail queue. */
} *n1, *n2, *np;

int main(int argc, char *argv[])
{
    int i;
    TAILQ_INIT(&head); /* Initialize the queue. */

    n1 = malloc(sizeof(struct entry)); /* Insert at the head. */
    n1->value = 10000;
    TAILQ_INSERT_HEAD(&head, n1, entries);

    for(i = 0; i < 10; i++)
    {
        n1 = malloc(sizeof(struct entry)); /* Insert at the tail. */
        n1->value = i;
        TAILQ_INSERT_TAIL(&head, n1, entries);
    }

    for(i = 10; i < 20; i++)
    {
        n2 = malloc(sizeof(struct entry)); /* Insert after. */
        n2->value = i;
        TAILQ_INSERT_AFTER(&head, n1, n2, entries);
    }
    /* Forward traversal. */
    for(np = head.tqh_first; np != NULL; np = np->entries.tqe_next)
    {
        printf("value is %d\n", np->value);
    }
    /* Delete. */
    while (head.tqh_first != NULL)
    {
        TAILQ_REMOVE(&head, head.tqh_first, entries);
    }

    return  0;
}

编译/运行后结果如下:

代码简短.不解释
-------------------------------------------------

c. CircularQueues接口代码CircularQueues.c

#include    <stdio.h>
#include    <stdlib.h>
#include    <sys/queue.h>

CIRCLEQ_HEAD(circleq, entry) head;
struct circleq *headp; /* Circular queue head. */
struct entry {
    int value;
    CIRCLEQ_ENTRY(entry) entries; /* Circular queue. */
} *n1, *n2, *np;

int main(int argc, char *argv[])
{
    int i;
    CIRCLEQ_INIT(&head); /* Initialize the circular queue. */

    n1 = malloc(sizeof(struct entry)); /* Insert at the head. */
    n1->value = 10000;
    CIRCLEQ_INSERT_HEAD(&head, n1, entries);

    for(i = 0; i < 10; i++)
    {
        n1 = malloc(sizeof(struct entry)); /* Insert at the tail. */
        n1->value = i;
        CIRCLEQ_INSERT_TAIL(&head, n1, entries);
    }

    //for(i = 10; i < 20; i++)
    for(i = 100; i < 101; i++)
    {
        n2 = malloc(sizeof(struct entry)); /* Insert after. */
        n2->value = i;
        CIRCLEQ_INSERT_AFTER(&head, n1, n2, entries);
    }

    //for(i = 20; i < 30; i++)
    for(i = 200; i < 201; i++)
    {
        n2 = malloc(sizeof(struct entry)); /* Insert before. */
        n2->value = i;
        CIRCLEQ_INSERT_BEFORE(&head, n1, n2, entries);
    }

    /* Forward traversal. */
    for (np = head.cqh_first; np != (void *)&head; np = np->entries.cqe_next)
    {
        printf("value is %d\n", np->value);
    }
    printf("\n----------------------------\n");
    /* Reverse traversal. */
    for (np = head.cqh_last; np != (void *)&head; np = np->entries.cqe_prev)
    {
        printf("value is %d\n", np->value);
    }
    /* Delete. */
    while (head.cqh_first != (void *)&head)
    {
        CIRCLEQ_REMOVE(&head, head.cqh_first, entries);
    }

    return  0;
}

编译/运行后结果如下:

代码简短.不解释
----------------------------------------------
2. 更多东东
    找"man queue"