alarm.cc

linux的例子,就是下载后到自己的机子上去运行

#include "system.h"


void loop(int which){
	while(alarm_clock->Getnum()!=0){
		currentThread->Yield();
	}
	currentThread->Finish();
}

Alarm::Alarm(char *debugname){
	name=debugname;
	pausenum=0;
	resttime=0;
	alarm_list = new List();
	alarm_lock = new Lock("alarm");
}

void
Alarm::Pause(int howLong){
	pausenum++;
	if(pausenum==1){
		Thread *t= new Thread("loop thread");
		t->Fork(loop,0);
	}
	if(howLong<=0)
		return;
	resttime=stats->totalTicks+howLong*TimerTicks*10;
	thread=currentThread;
	alarm_list->SortedInsert(currentThread,resttime);
	IntStatus oldLevel=interrupt->SetLevel(IntOff);
	currentThread->Sleep();
	interrupt->SetLevel(oldLevel);
}

void
Alarm::WakeUp(){
	Thread *th1;
	int ptime=0;
//	IntStatus oldLevel1=interrupt->SetLevel(IntOff);
	alarm_lock->Acquire();
	th1=(Thread*)alarm_list->SortedRemove(&ptime);
	alarm_lock->Release();
//	interrupt->SetLevel(oldLevel1);
	while(th1!=NULL){
		if(stats->totalTicks>=ptime){
			scheduler->ReadyToRun(th1);
			pausenum--;
//			IntStatus oldLevel2=interrupt->SetLevel(IntOff);
			alarm_lock->Acquire();
			th1=(Thread*)alarm_list->SortedRemove(&ptime);
			alarm_lock->Release();
//			interrupt->SetLevel(oldLevel2);
			continue;
		}
		else{
//			IntStatus oldLevel3=interrupt->SetLevel(IntOff);
			alarm_lock->Acquire();
			alarm_list->SortedInsert(th1,ptime);
			alarm_lock->Release();
//			interrupt->SetLevel(oldLevel3);
			break;
		}
	}
}