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

sem_t * ready;
sem_t * printed;
int maxN;
#define TRUE 1;
#define FALSE 0;

int keepGoing = TRUE;

pthread_mutex_t numLock = PTHREAD_MUTEX_INITIALIZER;

typedef struct param
{
	int value;
} param_t;


void *semprint(void * arg)
{
	while(keepGoing)
	{
		//pthread_mutex_lock(&numLock);
		sem_wait(ready); //wait for decrement
		printf("Value is: %d\n", maxN);
		//printf("notifying dec\n");
		sem_post(printed);//post for decrement
		//sem_wait(&ready); //wait for decrement
		//pthread_mutex_unlock(&numLock);
	}
	return NULL;
}

void *semdecrement(void * arg)
{
	while(keepGoing)
	{
		sem_wait(printed);//wait for readytodec
		if(maxN == 1)
		{
			keepGoing = FALSE;
		}
		//printf("past wait print\n");
		maxN--;
		sem_post(ready);//post for print

	}
	return NULL;
}

int main(int argc, char **argv)
{
	maxN = 10;
	sem_unlink("/ready");
	sem_unlink("/printed");


	ready = sem_open("/ready", O_CREAT, 0644, 1);
	printed = sem_open("/printed", O_CREAT, 0644, 0);

	if(ready == SEM_FAILED)
	{
		printf("ready open failed :(");
	}

	if(printed == SEM_FAILED)
	{
		printf("printed open failed :(");
	}

	//printf("READY IS: %d", ready);
	//printf("PRINTED IS: %d", printed);

	param_t data1;
	data1.value = 10;

	pthread_t printer;
	pthread_t decrementer;

	int printerT = pthread_create(&printer, NULL, semprint, &data1);
	int decrementerT = pthread_create(&decrementer, NULL, semdecrement, &data1);

	pthread_join(printer, NULL);
	pthread_join(decrementer, NULL);

	sem_close(ready);
	sem_close(printed);

	sem_unlink("/ready");
	sem_unlink("/printed");
	printf("Finished!\n");
	return 0;
}