elevator_stop.cc

linux的例子,就是下载后到自己的机子上去运行

#include"Elevator.h"
#include <malloc.h>

Elevator::Elevator(char *debugName,int numFloors,int myID)
{	
	int i;
	name = debugName;
	numfloors = numFloors;
	currentfloor = 1;
	elevstate = STOP;
	occupancy = 0;
	elevID = myID;
	fullnum = 10;
	dstfloor = new int[numfloors+1];
	elevlock = new Lock("elevtor lock");
	elevcond =(Condition **)malloc(sizeof(Condition*)*(numfloors+1));
	for(i=1;i<=numfloors;i++)
		elevcond[i] = new Condition("elevtor condition");
/*	upbarrier =(EventBarrier**)malloc(sizeof(EventBarrier*)*(numfloors+1));
	for(i=1;i<=numfloors;i++)
		upbarrier[i] = new EventBarrier("up barrier");
	downbarrier=(EventBarrier**)malloc(sizeof(EventBarrier*)*(numfloors+1));
	for(i=1;i<=numfloors;i++)
		downbarrier[i] = new EventBarrier("down barrier");
	wait=(EventBarrier**)malloc(sizeof(EventBarrier*)*(numfloors+1));
	for(i=1;i<=numfloors;i++)
		wait[i]=new EventBarrier("wait");*/
}

Elevator::~Elevator()
{
	delete dstfloor;
	delete elevlock;
	delete elevcond;
}	

void
Elevator::OpenDoors()
{
	elevlock->Acquire();
	elevcond[currentfloor]->Broadcast(elevlock);
	elevlock->Release();
	if(elevstate == UP){
		printf("before signal.\n");
		upbarrier[currentfloor]->Signal();
		/*if((upbarrier[currentfloor]->Waiters())==0)
			currentThread->Yield();*/
		printf("signal after.\n");
	}
	else if(elevstate==DOWN){
		downbarrier[currentfloor]->Signal();
		/*if((downbarrier[currentfloor]->Waiters())==0)
			currentThread->Yield();*/
	}
	dstfloor[currentfloor] = 0;
	elevlock->Acquire();
	elevcond[currentfloor]->Broadcast(elevlock);
	elevlock->Release();
}

void
Elevator::CloseDoors()
{
	/*if(elevstate == UP)
		upbarrier[currentfloor]->Complete();
	else
		downbarrier[currentfloor]->Complete();*/
	if(occupancy==0){
		elevstate=STOP;
	}
	return;
}

void
Elevator::VisitFloor(int floor)
{	
	if(currentfloor<floor)
		elevstate=UP;
	else if(currentfloor>floor)
		elevstate=DOWN;
	else{
		if((occupancy==0)&&(floor==0))
		elevstate=STOP;
	}
	currentfloor = floor;
	//wait[floor]->Signal();
//	OpenDoors();
//	CloseDoors();
}

int
Elevator::NextFloor()
{
	int u1,u2,d1,d2,i,j,result;
	while(1){
	u1=currentfloor;
	d2=currentfloor;
	i=currentfloor;
	j=currentfloor;
	u2=1;
	d1=numfloors;
	result=0;
	/*if(elevstate==STOP){ 
		conwait->Acquire();
		printf("no request,elevator stop.\n");
		wait->Wait(conwait);
		printf("call up or call down happen.\n");
		conwait->Release();
	}*/	
	if(occupancy > 0)
	{
	 	while(j <= numfloors && !dstfloor[j++]);
		while(i >= 1 && !dstfloor[i--]);
		j--;i++;
	}
	else{
		j=numfloors+1;
		i=0;
	}
	printf("i==%d,j==%d\n",i,j);
	while((u1<=numfloors) && !(upbarrier[u1++]->Waiters()));
	while((u2<=currentfloor) && !(upbarrier[u2++]->Waiters()));
	while((d1>=currentfloor) && !(downbarrier[d1--]->Waiters()));
	while((d2>=1) && !(downbarrier[d2--]->Waiters()));
	printf("u1=%d,u2=%d,d1=%d,d2=%d\n",u1,u2,d1,d2);
	printf("elevator %d currentfloor=%d\n",elevID,currentfloor);
	if(elevstate == UP|| elevstate==STOP )
	{
		if(u1 <= numfloors || j <= numfloors ){
			elevstate=UP;
			u1--;
			if(occupancy>0){
				result= (u1<=j)?u1:j;
			}
			else if(u1==10)
				result= 0;
			else 
				result= u1;
		}
		else if(d1 >= currentfloor)
   		{d1++;	elevstate = DOWN; result =  d1;}
		else if(d2 >= 1)
		{d2++;	elevstate = DOWN; result = d2;}
		else if(u2 <= currentfloor){
			u2--;
			elevstate=UP;
			result= u2;
		}
	}
	else 
	{
		if(d2 >= 1 || i >= 1 ){
			d2++;
			elevstate=DOWN;
			if(occupancy>0)
				result= (d2>=i)?d2:i;
			else if(d2==1)
				result=0;
			else
				result=d2;
		}
		else if(u2 <= currentfloor)
   		{u2--;	elevstate = UP; result= u2;}
		else if(u1 <= numfloors)
		{u1--;	elevstate = UP; result= u1;}
		else if(d1 >= currentfloor){
			d1++;
			elevstate=DOWN;
			result= d1;
		}
	}
	printf("result=%d.\n",result);
//	if((result==0)&&(elevstate==STOP)){
	if(result==0){ 
		conwait->Acquire();
		printf("no request,elevator stop.\n");
		wait->Wait(conwait);
		printf("call up or call down happen.\n");
		conwait->Release();
		
	}	
	else
		break;
	}
	return result;
}

bool
Elevator::Enter()
{
	if(occupancy < fullnum)
	{	
		++occupancy;
		return true;
	}
	else    return false;
}

void 
Elevator::Exit()
{
	--occupancy;
	if(occupancy==0)
		elevstate = STOP;
}

void
Elevator::RequestFloor(int floor)
{
	dstfloor[floor] = 1;
	elevlock->Acquire();
	elevcond[floor]->Wait(elevlock);
	printf("rider Request %d return.\n",floor);
	elevlock->Release();
}

//////////////////////////////////////////////////////////////////////
Building::Building(char *debugname,int numFloors,int numElevators)
{
	name = debugname;
	numfloors = numFloors;
	numelevators = numElevators;
	conwait = new Lock("conwati");
	int i;
	upbarrier =(EventBarrier**)malloc(sizeof(EventBarrier*)*(numfloors+1));
	for(i=1;i<=numfloors;i++)
		upbarrier[i] = new EventBarrier("up barrier");
	downbarrier=(EventBarrier**)malloc(sizeof(EventBarrier*)*(numfloors+1));
	for(i=1;i<=numfloors;i++)
		downbarrier[i] = new EventBarrier("down barrier");
	/*wait=(Condition**)malloc(sizeof(Condition*)*(numelevators+1));
	for(i=1;i<=numelevators;i++)
		wait[i]=new Condition("wait");*/
	wait=new Condition("wait");
	elevator=(Elevator **)malloc(sizeof(Elevator*)*(numElevators+1));
	for(i=1;i<=numelevators;++i)
	{
		elevator[i]= new Elevator("elevator",numfloors,i);
		elevator[i]->init(upbarrier,downbarrier,wait,conwait);
	}
}

Building::~Building()
{
	delete upbarrier;
	delete downbarrier;
	delete elevator;
}

void
Building::CallUp(int fromFloor)
{
	while(1){
	for(int i=1;i<=numelevators;i++)
		if((elevator[i]->GetState())==STOP){
		//	elevator[i]->SetState(UP);
			conwait->Acquire();
			wait->Broadcast(conwait);
			conwait->Release();
			return;
		}
	currentThread->Yield();
	}
//	upbarrier[fromFloor]->Wait();
}

void
Building::CallDown(int fromFloor)
{
	while(1){
	for(int i=1;i<=numelevators;i++)
		if((elevator[i]->GetState())==STOP){
		//	elevator[i]->SetState(DOWN);
			conwait->Acquire();
			wait->Broadcast(conwait);//elevator i  start
			conwait->Release();
			return;
		}
	currentThread->Yield();
	}
	//downbarrier[fromFloor]->Wait();
}

Elevator*
Building::AwaitUp(int fromFloor)
{
	int i;
	upbarrier[fromFloor]->Wait();
	//wait[fromFloor]->Wait();
	for(i=1;i<=numelevators;i++)
		if(elevator[i]->GetCurrentFloor()==fromFloor&&elevator[i]->GetState()==UP){
			//elevator[i]->SetState(UP);
			return elevator[i];
		}
	return 	NULL;
}

Elevator*
Building::AwaitDown(int fromFloor)
{
	int i;
	downbarrier[fromFloor]->Wait();
	//wait[fromFloor]->Wait();
	for(i=1;i<=numelevators;i++)
		if(elevator[i]->GetCurrentFloor()==fromFloor&&elevator[i]->GetState()==DOWN){
			//elevator[i]->SetState(DOWN);
			return elevator[i];
		}
	return NULL;
}