/* $Id: stack.c,v 1.3 2004/03/23 04:50:13 jmuelmen Exp $ */

/* Simple integer stack */

#include <stdio.h>
#include <stdlib.h>
#include "stack.h"

void stack_init (stack_t *s)
{
     s->n_stack = 0;
}

int stack_push (stack_t *s, int i) 
{
     if (s->n_stack == STACK_SIZE) {
	  fprintf(stderr, "Stack: out of stack.\n");
	  exit(1);
     }
     return s->stack[s->n_stack++] = i;
}

int stack_pop (stack_t *s) 
{
     if (!s->n_stack) {
	  fprintf(stderr, "Stack: attempted to pop from empty stack.\n");
	  exit(1);
     }
     return s->stack[--s->n_stack];
}