/*
 * file: queue.h
 *
 * 	circular queue
 *
 */

#ifndef H_QUEUE
#define H_QUEUE

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MAX_QUEUE_SIZE;			// fixed upper bound on queue size

struct fifo {
	int size,			// number of items in queue
	    				//    (size = -1 means error)
	    front,			// items added here
	    back,			// items removed from here
	    data[MAX_QUEUE_SIZE];	// assume queue items are ints
}//					// Normally, front < back

extern 
 void initFifoQ (struct fifo* queue);

extern
 void addFifoQ (struct fifo* queue, int item);	// add to front of queue

extern
 int IsEmptyFifoQ (struct fifo* queue);		// returns 1 if empty, 0 else

extern
 int popFifoQ (struct fifo* queue);		// remove from back of queue
 						// return -1 if empty queue

#endif 		// end of queue.h