/*
 *	Kitchen.cc
 *
 *	Multiple chef threads try to access a kitchen object to help with broth
 *
 *  1 February 2006 C. Scratchley	created to work with QNX 6.3.0
 *
 *  Copyright 2006, School of Engineering Science, SFU, Canada
 *  You may modify this software under the terms of the GNU GPL
*/

#include <iostream>
#include <pthread.h>
#include <unistd.h>
#include <semaphore.h>

using namespace std;

class brothClass
{
public:
	brothClass()
	{
	};
	void help(char id)
	{
		cout << "Chef " << id << " starting to help with broth" << endl;
		delay(2);
		cout << "Chef " << id << " finishing helping with broth" << endl;
	};
};

class kitchenClass
{
	sem_t sem4;
	brothClass broth;
	
public:
	kitchenClass()
	{
		sem_init(&sem4, 0, 2);	// allow 2 chefs in kitchen
	};
	void help(char identifier)
	{
		cout << "Chef " << identifier << 
			" asking for permission to help with broth" << endl;
		sem_wait(&sem4);
		broth.help(identifier);
		sem_post(&sem4);
	};
};

kitchenClass kitchen;

void* chef(void* arg) {
	char identifier = *((char*) arg);
	int n;
	for (n = 0; n < 2; n++){
 		kitchen.help(identifier);
		delay(1);
	};
	return NULL;
};
		
int main(int argc, char* argv[]) {
	pthread_t chefA, chefB, chefC;
	
	const char A = 'A';
	const char B = 'B';
	const char C = 'C';
	
	pthread_create( &chefA, NULL, chef, (void*) &A);
	pthread_create( &chefB, NULL, chef, (void*) &B);
	pthread_create( &chefC, NULL, chef, (void*) &C);
	
	pthread_join(chefA, NULL);
	pthread_join(chefB, NULL);
	pthread_join(chefC, NULL);	
	
	std::cout << "Primary thread ending" << std::endl;
	return EXIT_SUCCESS;
}