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/*
 * mq_receive.c - functions for receiving from message queue.
 */

#include <errno.h>
#include <stddef.h>
#include <sys/syscall.h>
#include <mqueue.h>
#warning FIXME: hard dependency on ADVANCED REALTIME feature

librt_hidden_proto(mq_timedreceive)
#ifdef __NR_mq_timedreceive
#define __NR___syscall_mq_timedreceive __NR_mq_timedreceive
static __inline__ _syscall5(int, __syscall_mq_timedreceive, int, mqdes,
			char *, msg_ptr, size_t, msg_len, unsigned int *,
			msg_prio, const void *, abs_timeout);
#endif

/*
 * Receive the oldest from highest priority messages.
 * Stop waiting if abs_timeout expires.
 */
ssize_t mq_timedreceive(mqd_t mqdes, char *msg_ptr, size_t msg_len,
			unsigned int *msg_prio,
			const struct timespec *abs_timeout)
{
#ifdef __NR_mq_timedreceive
	return __syscall_mq_timedreceive(mqdes, msg_ptr, msg_len, msg_prio,
					 abs_timeout);
#else
	errno = ENOSYS;
	return -1;
#endif
}

librt_hidden_def(mq_timedreceive)

/* Receive the oldest from highest priority messages */
ssize_t mq_receive(mqd_t mqdes, char *msg_ptr, size_t msg_len,
		   unsigned int *msg_prio)
{
	return mq_timedreceive(mqdes, msg_ptr, msg_len, msg_prio, NULL);
}