Message queues

Thread save message queues. More...

Typedefs
typedef struct bg_msg_queue_s	bg_msg_queue_t
	Opaque message queue type. You don't want to know what's inside.
Functions
bg_msg_queue_t *	bg_msg_queue_create ()
	Create a message queue.
void	bg_msg_queue_destroy (bg_msg_queue_t *mq)
	Destroy a message queue.
bg_msg_t *	bg_msg_queue_lock_read (bg_msg_queue_t *mq)
	Lock a message queue for reading.
bg_msg_t *	bg_msg_queue_try_lock_read (bg_msg_queue_t *mq)
	Try to lock a message queue for reading.
void	bg_msg_queue_unlock_read (bg_msg_queue_t *mq)
	Unlock a message queue for reading.
bg_msg_t *	bg_msg_queue_lock_write (bg_msg_queue_t *mq)
	Lock a message queue for writing.
void	bg_msg_queue_unlock_write (bg_msg_queue_t *mq)
	Unlock a message queue for writing.
int	bg_msg_queue_peek (bg_msg_queue_t *mq, uint32_t *id)
	Check, if there is a message for readinbg available and get the ID.

---

Detailed Description

Thread save message queues.

---

Typedef Documentation

typedef struct bg_msg_queue_s bg_msg_queue_t

Opaque message queue type. You don't want to know what's inside.

---

Function Documentation

bg_msg_queue_t* bg_msg_queue_create

(

)

Create a message queue.

Returns:

A newly allocated message queue

void bg_msg_queue_destroy

(

bg_msg_queue_t *

mq

)

Destroy a message queue.

Parameters:

mq	A message queue

bg_msg_t* bg_msg_queue_lock_read

(

bg_msg_queue_t *

mq

)

Lock a message queue for reading.

Parameters:

mq	A message queue

Returns:

A new message or NULL

This function blocks until a message arrives and returns the message. Use this function with caution to avoid deadlocks.

When you are done with the message, call bg_msg_queue_unlock_read. The message is owned by the queue and must not be freed.

bg_msg_t* bg_msg_queue_try_lock_read

(

bg_msg_queue_t *

mq

)

Try to lock a message queue for reading.

Parameters:

mq	A message queue

Returns:

A new message or NULL

This function immediately returns NULL if there is no message for reading. When you are done with the message, call bg_msg_queue_unlock_read. The message is owned by the queue and must not be freed.

void bg_msg_queue_unlock_read

(

bg_msg_queue_t *

mq

)

Unlock a message queue for reading.

Parameters:

mq	A message queue

Call this to signal, that you are done with a message.

bg_msg_t* bg_msg_queue_lock_write

(

bg_msg_queue_t *

mq

)

Lock a message queue for writing.

Parameters:

mq	A message queue

Returns:

An empty message, where you can place your information.

When you are done setting the ID and arguments, call bg_msg_queue_unlock_write.

void bg_msg_queue_unlock_write

(

bg_msg_queue_t *

mq

)

Unlock a message queue for writing.

Parameters:

mq	A message queue

Call this to signal, that you are done with a message.

int bg_msg_queue_peek	(	bg_msg_queue_t *	mq,
		uint32_t *	id
	)

Check, if there is a message for readinbg available and get the ID.

Parameters:

mq	A message queue
id	Might return the ID

Returns:

1 if there is a message (and id is valid), 0 else