#include <stdio.h>
#include <cothreads.h>

struct thr_state	t0,t1,t2,t3,t4;
int			s0[512], s1[512], s2[512], s3[512], s4[512];
struct lock		lck0, lck1;

void	worker(void	*arg)
{
	int	numeric_id = (int) arg;
	int	i;

	/* loop must be an even number of times so acquire/releases balance */
	for (i = 0; i < 512; i++) {
		printf("worker %d, top of loop %d\n",numeric_id,i);
		if ((numeric_id & 1) == 0) {
			if ((i & 1) == 0) {
				lock_acquire(&lck0);
				printf("worker %d, acquired\n",numeric_id);
				thr_yield();
			} else {
				thr_yield();
				lock_release(&lck0);
				printf("worker %d, released\n",numeric_id);
				thr_yield();
			}
		} else {
			if ((i & 1) == 0) {
				lock_acquire(&lck1);
				printf("worker %d, acquired\n",numeric_id);
				thr_yield();
			} else {
				lock_release(&lck1);
				printf("worker %d, released\n",numeric_id);
			}
		}
		thr_yield();
	}
}

void	spawner(void	*arg)
{
	char	*name = (char *) arg;
	int	i;

	printf("I am %s, spawning other threads\n",name);

	thr_init(&t1,worker,1,s1,2048);
	thr_init(&t2,worker,2,s2,2048);
	thr_init(&t3,worker,3,s3,2048);
	thr_init(&t4,worker,4,s4,2048);

	for (i = 0; i < 512; i++) {
		lock_acquire(&lck0);
		thr_yield();
		lock_acquire(&lck1);
		thr_yield();
	}
}

void main(void)
{
	lock_init(&lck0);
	lock_init(&lck1);
	thr_init(&t0,spawner,"spawner thread",s0,2048);
	thr_go();
	printf("All done!\n");
}