#ifndef LIBRARIES
#define LIBRARIES
#define _GNU_SOURCE
#include <fcntl.h> ///< For O_* constants *
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#endif

#include <semaphore.h> ///< For semaphores

#define FREE_SEM_NAME "/11777707_free"
#define USED_SEM_NAME "/11777707_used"
#define MUTEX_NAME "/11777707_mutex"

static sem_t *free_sem;
static sem_t *used_sem;
static sem_t *mutex;

sem_t * open_sem(char *sem_name, size_t sem_size) {
    sem_t *res = sem_open(sem_name, O_CREAT | O_EXCL, 0600, sem_size);
    if(res == SEM_FAILED) {
        fprintf(stderr, "ERROR: Failed opening semaphore\n");
        exit(EXIT_FAILURE);
    }
    return res;
}

void close_sem(sem_t *sem) {
    if(sem_close(sem) < 0) {
        fprintf(stderr, "ERROR: Failed closing semaphore\n");
        exit(EXIT_FAILURE);
    }
}

void destroy_sem(char *sem_name) {
    if(sem_unlink(sem_name) < 0) {
        fprintf(stderr, "ERROR: Failed closing semaphore\n");
        exit(EXIT_FAILURE);
    }
}