#ifndef MQUEUE_H
#define MQUEUE_H

/*
 * This header file defines constants and function declarations used for
 * MINIX interprocess message queues. These are used primarily in file
 * mqueue.c
 */

#include <minix/type.h>

#define MAX_RECEIVERS	4
#define MAX_MESSAGES	64
#define MAX_QUEUES	64
#define MAX_PAYLOAD	32
#define NAME_SIZE	32
#define DEFAULT_PRIO	0

#define EMPTY		-1
#define NOT_EMPTY	1

typedef int mqd_t;

typedef struct message_entity {
	u64_t timestamp;
	char msg[MAX_PAYLOAD];
	endpoint_t src;
	endpoint_t dst[MAX_RECEIVERS];
	unsigned int priority;
} message_entity;

typedef struct messageq {
	char name[NAME_SIZE];
	int num_msgs;
	message_entity msge[MAX_MESSAGES];
	int msg_slot_empty[MAX_MESSAGES];
} messageq;

typedef struct message_queue {
	int num_queues;
	messageq msg[MAX_QUEUES];
	int queue_slot_empty[MAX_QUEUES];
} message_queue;

int initialize_message_queues(void);
int deinitialize_message_queues(void);

mqd_t mq_open(const char *name, int oflag);
int mq_send(mqd_t mqdes, const char *msg_ptr, unsigned int msg_prio, endpoint_t src, endpoint_t dst[]);
size_t mq_receive(mqd_t mqdes, char *msg_ptr, unsigned int msg_prio, endpoint_t dst);
int mq_close(mqd_t mqdes);

int clean_message_queue(mqd_t mqdes);
int message_index_with_highprio(mqd_t mqdes, endpoint_t dst);

#endif /* MQUEUE_H */