ll-timers.cc

一个很好的LINUX底下的GPRS协议栈

/* -*-	Mode:C++; c-basic-offset:8; tab-width:8; indent-tabs-mode:t -*- */

/* By Sandeep Kumar, Kopparapu Suman and Richa Jain,
 * Indian Institute of Technology, Bombay.
 * June, 2001.
*/ 

/* Copyright (c) 2001 Indian Insitute of Technology, Bombay.  
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * 1. Redistributions of source code and binary code must contain
 * the above copyright notice, this list of conditions and the following 
 * disclaimer.
 * 
 * 2. All advertising materials mentioning features or use of this software
 * must display the following acknowledgement: 
 * This product includes software developed at Indian Insitute of
 * Technology, Bombay. 
 *
 * 3. The name of the Institute may not be used to endorse or promote 
 * products derived from this software without specific prior written 
 * permission.
 * INDIAN INSTITUTE OF TECHNOLOGY, BOMBAY, MAKES NO REPRESENTATIONS 
 * CONCERNING EITHER THE MERCHANTABILITY OF THIS SOFTWARE OR THE 
 * SUITABILITY OF THIS SOFTWARE FOR ANY PARTICULAR PURPOSE.  The software 
 * is provided "as is" without express or implied warranty of any kind.
*/

#include <delay.h>
#include <connector.h>
#include <packet.h>
#include <random.h>
 
// #define DEBUG
//#include <debug.h>
#include <arp.h>
#include <ll.h>
#include <mac.h>
#include <ll-timers.h>

/*
 * Force timers to expire on slottime boundries.
 */
// #define USE_SLOT_TIME

#define ROUND_TIME()	\
	{								\
		assert(slottime);					\
		double rmd = remainder(s.clock() + rtime, slottime);	\
		if(rmd > 0.0)						\
			rtime += (slottime - rmd);			\
		else							\
			rtime += (-rmd);				\
	}


/* ======================================================================
   Timers
   ====================================================================== */

void
LLTimer::start(double time)
{
	Scheduler &s = Scheduler::instance();
	assert(busy_ == 0);
	
	busy_ = 1;
	paused_ = 0;
	stime = s.clock();
	rtime = time;
	assert(rtime >= 0.0);
//	fprintf(stderr,"ll timer started\n");

	s.schedule(this, &intr, rtime);
}

void
LLTimer::stop(void)
{
	Scheduler &s = Scheduler::instance();
	
//	fprintf(stderr,"ll timer stopped\n");
	assert(busy_);

	if(paused_ == 0)
		s.cancel(&intr);

	busy_ = 0;
	paused_ = 0;
	stime = 0.0;
	rtime = 0.0;
}

/* ======================================================================
   Send Timer
   ====================================================================== */
void llTxTimer::handle(Event *)
{       
	busy_ = 0;
	paused_ = 0;
	stime = 0.0;
	rtime = 0.0;

	ll->sendHandler();
}

void llackTimer::handle(Event *)
{       
	busy_ = 0;
	paused_ = 0;
	stime = 0.0;
	rtime = 0.0;

	ll->sendackHandler();
}