buzzer.cc.svn-base

德国Erlangen大学教学操作系统源码。

/*****************************************************************************/
/* Betriebssysteme                                                           */
/*---------------------------------------------------------------------------*/
/*                                                                           */
/*                               B U Z Z E R                                 */
/*                                                                           */
/*---------------------------------------------------------------------------*/
/* Mit Hilfe des "Weckers" koennen Prozesse eine bestimmte Zeit lang         */
/* schlafen und sich dann wecken lassen.                                     */
/*****************************************************************************/

#include "device/watch.h"

#include "meeting/bell.h"
#include "meeting/buzzer.h"
#include "meeting/bellringer.h"
#include "syscall/guarded_organizer.h"

#include "device/cgastr.h"
extern CGA_Stream kout;

extern Watch watch;
extern Guarded_Organizer scheduler;
extern Bellringer bellringer;

Buzzer::Buzzer()
{
}

Buzzer::Buzzer(Buzzer& buzzer)
{
}

Buzzer::~Buzzer()
{
}
	
void Buzzer::ring()
{
	Customer *cust = static_cast<Customer*>(dequeue());
	while(cust) {
		scheduler.Organizer::wakeup(*cust);
		Customer* cust2 = static_cast<Customer*>(dequeue());
		if(cust2 == cust || cust2->next == cust || cust->next == cust2) {
			kout.goto_head();
		} else
			cust = cust2;
	}
}

void Buzzer::set (int ms)
{	
	wait(ms*1000/watch.interval());
}

void Buzzer::sleep ()
{
	Customer *cust = static_cast<Customer*>(scheduler.Scheduler::active());
	remove(cust);
	enqueue(cust);
	bellringer.job(this, wait());
	scheduler.Organizer::block(*cust, *this);
}