非常实用，推荐一种面向对象思维的单片机程序框架

程序架构重要性

但是操作系统的调度过于复杂，这里就使用操作系统的思维方式来重构这个时间片轮询框架。实现该框架的完全解耦，用户只需要包含头文件，并且在使用过程中不需要改动已经写好的库文件。

首先来个demo，该demo是使用电脑开两个线程：一个线程模拟单片机的定时器中断产生时间片轮询个时钟，另一个线程则模拟主函数中一直运行的时间片轮询调度程序。

#include<thread>#include <stdio.h>#include <windows.h>#include "timeslice.h"
// 创建5个任务对象TimesilceTaskObj task_1, task_2, task_3, task_4, task_5;
// 具体的任务函数void task1_hdl(){    printf(">> task 1 is running ...\n");}
void task2_hdl(){    printf(">> task 2 is running ...\n");}
void task3_hdl(){    printf(">> task 3 is running ...\n");}
void task4_hdl(){    printf(">> task 4 is running ...\n");}
void task5_hdl(){    printf(">> task 5 is running ...\n");}
// 初始化任务对象，并且将任务添加到时间片轮询调度中void task_init(){    timeslice_task_init(task_1, task1_hdl, 1, 10);    timeslice_task_init(task_2, task2_hdl, 2, 20);    timeslice_task_init(task_3, task3_hdl, 3, 30);    timeslice_task_init(task_4, task4_hdl, 4, 40);    timeslice_task_init(task_5, task5_hdl, 5, 50);    timeslice_task_add(task_1);    timeslice_task_add(task_2);    timeslice_task_add(task_3);    timeslice_task_add(task_4);    timeslice_task_add(task_5);}

// 开两个线程模拟在单片机上的运行过程void timeslice_exec_thread(){    while (true)    {        timeslice_exec();    }}
void timeslice_tick_thread(){    while (true)    {        timeslice_tick();        Sleep(10);    }}
int main(){    task_init();
    printf(">> task num: %d\n", timeslice_get_task_num());    printf(">> task len: %d\n", timeslice_get_task_timeslice_len(task_3));
    timeslice_task_del(task_2);    printf(">> delet task 2\n");    printf(">> task 2 is exist: %d\n", timeslice_task_isexist(task_2));
    printf(">> task num: %d\n", timeslice_get_task_num());
    timeslice_task_del(task_5);    printf(">> delet task 5\n");
    printf(">> task num: %d\n", timeslice_get_task_num());
    printf(">> task 3 is exist: %d\n", timeslice_task_isexist(task_3));    timeslice_task_add(task_2);    printf(">> add task 2\n");    printf(">> task 2 is exist: %d\n", timeslice_task_isexist(task_2));
    timeslice_task_add(task_5);    printf(">> add task 5\n");
    printf(">> task num: %d\n", timeslice_get_task_num());
    printf("\n\n========timeslice running===========\n");
    std::thread thread_1(timeslice_exec_thread);    std::thread thread_2(timeslice_tick_thread);
    thread_1.join();    thread_2.join();

    return 0;}

运行结果如下：

时间片轮询架构

其实该部分主要使用了面向对象的思维，使用结构体作为对象，并使用结构体指针作为参数传递，这样作可以节省资源，并且有着极高的运行效率。

h文件：

#ifndef_TIMESLICE_H#define _TIMESLICE_H
#include "./list.h"
typedef enum {    TASK_STOP,    TASK_RUN} IsTaskRun;
typedef struct timesilce{    unsigned int id;    void (*task_hdl)(void);    IsTaskRun is_run;    unsigned int timer;    unsigned int timeslice_len;    ListObj timeslice_task_list;} TimesilceTaskObj;
void timeslice_exec(void);void timeslice_tick(void);void timeslice_task_init(TimesilceTaskObj* obj, void (*task_hdl)(void), unsigned int id, unsigned int timeslice_len);void timeslice_task_add(TimesilceTaskObj* obj);void timeslice_task_del(TimesilceTaskObj* obj);unsigned int timeslice_get_task_timeslice_len(TimesilceTaskObj* obj);unsigned int timeslice_get_task_num(void);unsigned char timeslice_task_isexist(TimesilceTaskObj* obj);
#endif

#include"./timeslice.h"
static LIST_HEAD(timeslice_task_list);
void timeslice_exec(){    ListObj* node;    TimesilceTaskObj* task;
    list_for_each(node, timeslice_task_list)    {
        task = list_entry(node, TimesilceTaskObj, timeslice_task_list);        if (task->is_run == TASK_RUN)        {            task->task_hdl();            task->is_run = TASK_STOP;        }    }}
void timeslice_tick(){    ListObj* node;    TimesilceTaskObj* task;
    list_for_each(node, timeslice_task_list)    {        task = list_entry(node, TimesilceTaskObj, timeslice_task_list);        if (task->timer != 0)        {            task->timer--;            if (task->timer == 0)            {                task->is_run = TASK_RUN;                task->timer = task->timeslice_len;            }        }    }}
unsigned int timeslice_get_task_num(){    return list_len(timeslice_task_list);}
void timeslice_task_init(TimesilceTaskObj* obj, void (*task_hdl)(void), unsigned int id, unsigned int timeslice_len){    obj->id = id;    obj->is_run = TASK_STOP;    obj->task_hdl = task_hdl;    obj->timer = timeslice_len;    obj->timeslice_len = timeslice_len;}
void timeslice_task_add(TimesilceTaskObj* obj){    list_insert_before(timeslice_task_list, obj->timeslice_task_list);}
void timeslice_task_del(TimesilceTaskObj* obj){    if (timeslice_task_isexist(obj))        list_remove(obj->timeslice_task_list);    else        return;}

unsigned char timeslice_task_isexist(TimesilceTaskObj* obj){    unsigned char isexist = 0;    ListObj* node;    TimesilceTaskObj* task;
    list_for_each(node, timeslice_task_list)    {        task = list_entry(node, TimesilceTaskObj, timeslice_task_list);        if (obj->id == task->id)            isexist = 1;    }
    return isexist;}
unsigned int timeslice_get_task_timeslice_len(TimesilceTaskObj* obj){    return obj->timeslice_len;}

底层侵入式双向链表

该链表是linux内核中使用十分广泛，也十分经典，其原理具体可以参考文章：

https://www.cnblogs.com/skywang12345/p/3562146.html

h文件：

#ifndef_LIST_H#define _LIST_H
#define offset_of(type, member)             (unsigned long) ((type*)0)->member#define container_of(ptr, type, member)     ((type *)((char *)(ptr) - offset_of(type, member)))
typedef struct list_structure{    struct list_structure* next;    struct list_structure* prev;} ListObj;
#define LIST_HEAD_INIT(name)    {(name), (name)}#define LIST_HEAD(name)         ListObj name = LIST_HEAD_INIT(name)
void list_init(ListObj* list);void list_insert_after(ListObj* list, ListObj* node);void list_insert_before(ListObj* list, ListObj* node);void list_remove(ListObj* node);int list_isempty(const ListObj* list);unsigned int list_len(const ListObj* list);
#define list_entry(node, type, member) \    container_of(node, type, member)
#define list_for_each(pos, head) \    for (pos = (head)->next; pos != (head); pos = pos->next)
#define list_for_each_safe(pos, n, head) \  for (pos = (head)->next, n = pos->next; pos != (head); \    pos = n, n = pos->next)
#endif

c文件：

#include"list.h"
void list_init(ListObj* list){    list->next = list->prev = list;}
void list_insert_after(ListObj* list, ListObj* node){    list->next->prev = node;    node->next = list->next;
    list->next = node;    node->prev = list;}
void list_insert_before(ListObj* list, ListObj* node){    list->prev->next = node;    node->prev = list->prev;
    list->prev = node;    node->next = list;}
void list_remove(ListObj* node){    node->next->prev = node->prev;    node->prev->next = node->next;
    node->next = node->prev = node;}
int list_isempty(const ListObj* list){    return list->next == list;}
unsigned int list_len(const ListObj* list){    unsigned int len = 0;    const ListObj* p = list;    while (p->next != list)    {        p = p->next;        len++;    }
    return len;}

来源：小麦大叔