Thread-safe queues (FIFO)

Collaboration diagram for Thread-safe queues (FIFO):

Modules
	Queue internals
	Low-level queue functions.
	Killable queues
	Thread-safe queues with an end flag.

Files
file	vlc_queue.h

Data Structures
struct	vlc_queue
	Thread-safe queue (a.k.a. More...

Typedefs
typedef struct vlc_queue	vlc_queue_t
	Thread-safe queue (a.k.a.

Functions
void	vlc_queue_Init (vlc_queue_t *queue, ptrdiff_t next_offset)
	Initializes a queue.
void	vlc_queue_Enqueue (vlc_queue_t *q, void *entry)
	Queues an entry.
void *	vlc_queue_Dequeue (vlc_queue_t *queue)
	Dequeues the oldest entry.
void *	vlc_queue_DequeueAll (vlc_queue_t *)
	Dequeues all entries.

Detailed Description

Typedef Documentation

vlc_queue_t

typedef struct vlc_queue vlc_queue_t

Thread-safe queue (a.k.a.

FIFO).

Function Documentation

vlc_queue_Dequeue()

void * vlc_queue_Dequeue

(

vlc_queue_t *

queue

)

Dequeues the oldest entry.

This function dequeues an entry from a thread-safe queue. If the queue is empty, it will wait until at least one entry is available.

Parameters

queue

queue object to dequeue an entry from

Returns

the first entry in the queue, or NULL if the queue is empty

References vlc_queue_DequeueUnlocked(), vlc_queue_IsEmpty(), vlc_queue_Lock(), vlc_queue_Unlock(), vlc_queue_Wait(), and vlc_testcancel().

vlc_queue_DequeueAll()

void * vlc_queue_DequeueAll

(

vlc_queue_t *

q

)

Dequeues all entries.

This is equivalent to calling vlc_queue_Dequeue() repeatedly until the queue is emptied. However this function is much faster than that, as it does not need to update the linked-list pointers.

Returns

a linked-list of all entries (possibly NULL if none)

References vlc_queue_DequeueAllUnlocked(), vlc_queue_Lock(), and vlc_queue_Unlock().

vlc_queue_Enqueue()

void vlc_queue_Enqueue	(	vlc_queue_t *	q,
		void *	entry
	)

Queues an entry.

This function enqueues an entry, or rather a linked-list of entries, in a thread-safe queue.

Parameters

q	A queue initialized with vlc_queue_Init
entry	list of entries (if NULL, this function has no effects)

References vlc_queue_EnqueueUnlocked(), vlc_queue_Lock(), and vlc_queue_Unlock().

vlc_queue_Init()

void vlc_queue_Init	(	vlc_queue_t *	queue,
		ptrdiff_t	next_offset
	)

Initializes a queue.

Parameters

queue	storage space for the queue
next_offset	offset of the pointer to the next element within a queue entry (as per offsetof())

References vlc_queue::first, vlc_queue::lastp, vlc_queue::lock, vlc_queue::next_offset, vlc_cond_init(), vlc_mutex_init(), and vlc_queue::wait.

Referenced by vlc_fifo_New(), and vlc_stream_fifo_New().