使用setjmp,longjmp函数模拟多任务实时操作系统

/*******filename:xiaohw***** author:xiaohw Datetime:20090324 21:58 ***********/ #include<windows.h> #include "MMSystem.h" #include "setjmptest.h" #include<stdio.h> #define TIMER_INTERVAL 10 #define TIMER_ACCURACY 1 task_manage GloablMyTaskManage; MMRESULT g_timer_wid; void main(); void CALLBACK mtimer_task(UINT wTimerID,UINT nMsg,DWORD dwUser,DWORD dw1,DWORD dw2) { unsigned char i; for(i=0;i<=MAXTASK-1;i++) { if(DELAY==GloablMyTaskManage.taskTcp[i].status) { GloablMyTaskManage.taskTcp[i].sleepTimeCount= (GloablMyTaskManage.taskTcp[i].sleepTimeCount-10)>0 ?(GloablMyTaskManage.taskTcp[i].sleepTimeCount-10):0; } } } void mtimer_sys_init() { g_timer_wid= timeSetEvent(TIMER_INTERVAL, TIMER_ACCURACY, mtimer_task, NULL, TIME_PERIODIC ); } TASKID FindNextReadTask()/****查找下个应该运行的任务******/ { unsigned char i; for(i=0;i<=MAXTASK-1;i++)/**向后查找（优先级低）**/ { if(READY==GloablMyTaskManage.taskTcp[i].status||AWAKENING==GloablMyTaskManage.taskTcp[i].status) { return i; } if((DELAY==GloablMyTaskManage.taskTcp[i].status)&&(0==GloablMyTaskManage.taskTcp[i].sleepTimeCount)) { return i; } } return MAXTASK-1; } void InitTaskManage()/***初始化任务管理器，将main函数作为最低优先级的任务****/ { int i=0; GloablMyTaskManage.taskTcp[MAXTASK-1].status=READY; GloablMyTaskManage.taskTcp[MAXTASK-1].sleepTimeCount=0; GloablMyTaskManage.taskTcp[MAXTASK-1].TaskFunction=main; for(;i<=MAXTASK-2;i++) { GloablMyTaskManage.taskTcp[i].status=DELETED; GloablMyTaskManage.taskTcp[i].sleepTimeCount=0; GloablMyTaskManage.taskTcp[i].TaskFunction=NULL; } GloablMyTaskManage.curRunTaskID=MAXTASK-1; } TASKID CreatMyTask(FUNCTASK fun,unsigned char priority)/****创建任务***/ { if(priority>=(MAXTASK-1)||priority<0) { return -1; } if(GloablMyTaskManage.taskTcp[priority].status!=DELETED) { return -1; } GloablMyTaskManage.taskTcp[priority].sleepTimeCount=0; GloablMyTaskManage.taskTcp[priority].status=READY; GloablMyTaskManage.taskTcp[priority].TaskFunction=fun; return priority; } int DestoryMyTask(TASKID taskid)/****销毁任务******/ { if(MAXTASK-1<taskid||taskid<0) { return -1; } GloablMyTaskManage.taskTcp[taskid].status=DELETED; GloablMyTaskManage.taskTcp[taskid].sleepTimeCount=0; GloablMyTaskManage.taskTcp[taskid].TaskFunction=NULL; return 1; } void MyTaskSleep(unsigned int mstime) { unsigned char temp; GloablMyTaskManage.taskTcp[GloablMyTaskManage.curRunTaskID].status=DELAY; GloablMyTaskManage.taskTcp[GloablMyTaskManage.curRunTaskID].sleepTimeCount=mstime; temp=FindNextReadTask(); GloablMyTaskManage.curRunTaskID=temp; if(DELAY==GloablMyTaskManage.taskTcp[temp].status||AWAKENING==GloablMyTaskManage.taskTcp[temp].status)/***唤起和延时的任务，使用跳转***/ { longjmp(GloablMyTaskManage.taskTcp[temp].Task_Env,0); } else if(READY==GloablMyTaskManage.taskTcp[temp].status)/**就绪的任务是第一次调用，直接执行他的功能函数***/ { (GloablMyTaskManage.taskTcp[temp].TaskFunction)(); } else { printf("temp=%d\n",temp); printf("error\n"); } } void MyTaskSuspend()/****任务自身挂起****/ { unsigned char temp; GloablMyTaskManage.taskTcp[GloablMyTaskManage.curRunTaskID].status=SUSPEND; temp=FindNextReadTask(); GloablMyTaskManage.curRunTaskID=temp; if(DELAY==GloablMyTaskManage.taskTcp[temp].status) { longjmp(GloablMyTaskManage.taskTcp[temp].Task_Env,0); } else if(READY==GloablMyTaskManage.taskTcp[temp].status) { printf("exec\n"); (GloablMyTaskManage.taskTcp[temp].TaskFunction)(); } else { printf("temp=%d\n",temp); printf("error\n"); } } int MyTaskResume(TASKID taskid)/*****唤醒任务*****/ { if(SUSPEND==GloablMyTaskManage.taskTcp[GloablMyTaskManage.curRunTaskID].status) { GloablMyTaskManage.taskTcp[GloablMyTaskManage.curRunTaskID].status=AWAKENING; return 1; } return -1; } void task1() { while (1) { if(setjmp(GloablMyTaskManage.taskTcp[GloablMyTaskManage.curRunTaskID].Task_Env)==0) { MyTaskSleep(100); } else { printf("task1\n"); continue; } } } void task2() { while (1) { if(setjmp(GloablMyTaskManage.taskTcp[GloablMyTaskManage.curRunTaskID].Task_Env)==0) { MyTaskSleep(100); } else { printf("task2\n"); continue; } } } void task3() { while (1) { if(setjmp(GloablMyTaskManage.taskTcp[GloablMyTaskManage.curRunTaskID].Task_Env)==0) { MyTaskSleep(100); } else { printf("task3\n"); continue; } } } void main() { TASKID task1ID,task2ID,task3ID; InitTaskManage(); mtimer_sys_init(); task1ID=CreatMyTask(task1,3); task2ID=CreatMyTask(task2,2); task3ID=CreatMyTask(task3,5); while (1) { if(setjmp(GloablMyTaskManage.taskTcp[GloablMyTaskManage.curRunTaskID].Task_Env)==0) { MyTaskSleep(100); } else { continue; } } }