scheduler.h

可以在ns-2中进行仿真的SPIN路由协议的源码

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/*
 * Copyright (c) 1994 Regents of the University of California.
 * All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
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 * 1. Redistributions of source code must retain the above copyright
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 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the Computer Systems
 *	Engineering Group at Lawrence Berkeley Laboratory.
 * 4. Neither the name of the University nor of the Laboratory may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * @(#) $Header: /usr/src/mash/repository/vint/ns-2/scheduler.h,v 1.15 1998/12/24 22:58:52 polly Exp $ (LBL)
 */

#ifndef ns_scheduler_h
#define ns_scheduler_h

#include <tclcl.h>

class Handler;

class Event {
public:
	Event* next_;		/* event list */
	Handler* handler_;	/* handler to call when event ready */
	double time_;		/* time at which event is ready */
	int uid_;		/* unique ID */
	Event() : time_(0), uid_(0) {}
};

/*
 * The base class for all event handlers.  When an event's scheduled
 * time arrives, it is passed to handle which must consume it.
 * i.e., if it needs to be freed it, it must be freed by the handler.
 */
class Handler {
 public:
	virtual void handle(Event* event) = 0;
};

#define	SCHED_START	0.0	/* start time (secs) */

class Scheduler : public TclObject {
public:
	static Scheduler& instance() {
		return (*instance_);		// general access to scheduler
	}
	void schedule(Handler*, Event*, double delay);	// sched later event
	virtual void run();			// execute the simulator
	virtual void cancel(Event*) = 0;	// cancel event
	virtual void insert(Event*) = 0;	// schedule event
	virtual Event* lookup(int uid) = 0;	// look for event
	virtual Event* deque() = 0;		// next event (removes from q)
	inline double clock() const {		// simulator virtual time
		return (clock_);
	}
	virtual void sync() {};
	virtual double start() {		// start time
		return SCHED_START;
	}
	inline void reset() { clock_ = SCHED_START; }/*XXX*/
protected:
	void dumpq();	// for debug: remove + print remaining events
	void dispatch(Event*);	// execute an event
	void dispatch(Event*, double);	// exec event, set clock_
	Scheduler();
	int command(int argc, const char*const* argv);
	double clock_;
	int halted_;
	static Scheduler* instance_;
	static int uid_;
};
#endif