#include <stdio.h>
#include <pthread.h>

#define MAX	1000000000
 
pthread_mutex_t the_mutex;
pthread_cond_t condc, condp;
int buffer = 0;

void *producer(void *ptr)
{
	int i;
	for(i = 1; i < MAX; i++)
	{
		pthread_mutex_lock(&the_mutex); //get exclusive access to buffer
		while(buffer != 0) pthread_cond_wait(&condp, &the_mutex);
		buffer = i;						//put item in the buffer
		pthread_cond_signal(&condc);	//wake up consumer
		printf("Produced! Buffer: %i\n", buffer);
		pthread_mutex_unlock(&the_mutex);	//release access to buffer
	}
	pthread_exit(NULL);
}

void *consumer(void *ptr)
{
	int i;
	for(i = 1; i < MAX; i++)
	{
		pthread_mutex_lock(&the_mutex); //get exclusive access to buffer
		while(buffer == 0) pthread_cond_wait(&condc, &the_mutex);
		buffer = 0;						//put item in the buffer
		pthread_cond_signal(&condp);	//wake up consumer
		printf("Consumed! Buffer: %i\n", buffer);
		pthread_mutex_unlock(&the_mutex);	//release access to buffer
	}
	pthread_exit(NULL);
}

int main(int argc, char **argv)
{
	pthread_t pro, con;
	pthread_mutex_init(&the_mutex, 0);
	pthread_cond_init(&condc, 0);
	pthread_cond_init(&condp, 0);
	pthread_create(&con, 0, consumer, 0);
	pthread_create(&pro, 0, producer, 0);
	pthread_join(pro, 0);	
	pthread_join(con, 0);
	pthread_cond_destroy(&condc);
	pthread_cond_destroy(&condp);
	pthread_mutex_destroy(&the_mutex);
}