#include <sys/types.h>
#include <sys/socket.h>
#include <sys/syscall.h>
#include <unistd.h>
#include <stdio.h>
#include <limits.h>
#include <stdarg.h> 
#include <errno.h>
#include <string.h>
#include <poll.h>
#include <asm/fcntl.h>

#define __NR_mq_open 277
#define __NR_mq_unlink 278
#define __NR_mq_timedsend 279
#define __NR_mq_timedreceive 280
#define __NR_mq_notify 281
#define __NR_mq_getsetattr 282

typedef int mdq_t;

struct mq_attr { 
	long mq_flags;
	long mq_maxmsg;
	long mq_msgsize;	
	long mq_curmsgs;
	long	__reserved[4];
};

static inline int __mq_open (const char *name, int oflag, mode_t mode, struct mq_attr *attr) 
{
	return syscall(__NR_mq_open, name, oflag, mode, attr);
}

static inline int __mq_timedreceive(mdq_t des, char *msgptr, size_t msglen, 
			unsigned int *msgprio, const struct timespec *abs_timeout) 
{
	return syscall(__NR_mq_timedreceive, des, msgptr, msglen, msgprio, abs_timeout);
}

static inline int __mq_timedsend(mdq_t mqdes, const char *msg_ptr, 
			size_t msglen, unsigned int msgprio,
			const struct timespec *abs_timeout) 
{ 
	return(syscall, __NR_mq_timedsend, mqdes, msg_ptr, msglen, msgprio, abs_timeout);
}

static int mq_send(mdq_t des, const char *msgptr, size_t msglen, unsigned int msgprio) { 
	return __mq_timedsend(des, msgptr, msglen, msgprio, NULL);
}

ssize_t mq_receive(mdq_t des, char *msgptr, size_t msglen, unsigned int *msgprio) {
	return __mq_timedreceive(des, msgptr, msglen, msgprio, NULL);
}

mdq_t mq_open(const char *name, int oflag, ...)
{
	unsigned long mode;	
	struct mq_attr *attr;
	va_list	ap;

	va_start(ap, oflag);
	mode = va_arg(ap, unsigned long);
	attr = va_arg(ap, struct mq_attr *);
	va_end(ap);

	return __mq_open(name, oflag, mode, attr);

}

#define PRIO 1
#define QUEUE "/mnt/example_queue"
#define SIZE 17000

void main()  {

	mdq_t ds;
	char text[SIZE];
	unsigned int msg_prio = 1;

	ds = open(QUEUE, O_RDONLY|O_CREAT); 
	
	if (ds == -1) {
		perror("Opening queue error\n");
		exit(1);
	}

	if (mq_receive(ds, text, SIZE, &msg_prio) == -1)
		perror("Receiving message error");
	else
		printf("Message received: %s\n", text);

	return 0;
}