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Enumerations | Functions
threadmessage.h File Reference

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Enumerations

enum  AVThreadMessageFlags { AV_THREAD_MESSAGE_NONBLOCK = 1 }
 

Functions

int av_thread_message_queue_alloc (AVThreadMessageQueue **mq, unsigned nelem, unsigned elsize)
 Allocate a new message queue. More...
 
void av_thread_message_queue_free (AVThreadMessageQueue **mq)
 Free a message queue. More...
 
int av_thread_message_queue_send (AVThreadMessageQueue *mq, void *msg, unsigned flags)
 Send a message on the queue. More...
 
int av_thread_message_queue_recv (AVThreadMessageQueue *mq, void *msg, unsigned flags)
 Receive a message from the queue. More...
 
void av_thread_message_queue_set_err_send (AVThreadMessageQueue *mq, int err)
 Set the sending error code. More...
 
void av_thread_message_queue_set_err_recv (AVThreadMessageQueue *mq, int err)
 Set the receiving error code. More...
 
void av_thread_message_queue_set_free_func (AVThreadMessageQueue *mq, void(*free_func)(void *msg))
 Set the optional free message callback function which will be called if an operation is removing messages from the queue. More...
 
int av_thread_message_queue_nb_elems (AVThreadMessageQueue *mq)
 Return the current number of messages in the queue. More...
 
void av_thread_message_flush (AVThreadMessageQueue *mq)
 Flush the message queue. More...
 

Enumeration Type Documentation

◆ AVThreadMessageFlags

Enumerator
AV_THREAD_MESSAGE_NONBLOCK 

Perform non-blocking operation.

If this flag is set, send and recv operations are non-blocking and return AVERROR(EAGAIN) immediately if they can not proceed.

Definition at line 24 of file threadmessage.h.

Function Documentation

◆ av_thread_message_queue_alloc()

int av_thread_message_queue_alloc ( AVThreadMessageQueue **  mq,
unsigned  nelem,
unsigned  elsize 
)

Allocate a new message queue.

Parameters
mqpointer to the message queue
nelemmaximum number of elements in the queue
elsizesize of each element in the queue
Returns
>=0 for success; <0 for error, in particular AVERROR(ENOSYS) if lavu was built without thread support

Definition at line 40 of file threadmessage.c.

Referenced by android_camera_read_header(), fifo_init(), and main().

◆ av_thread_message_queue_free()

void av_thread_message_queue_free ( AVThreadMessageQueue **  mq)

Free a message queue.

The message queue must no longer be in use by another thread.

Definition at line 91 of file threadmessage.c.

Referenced by android_camera_read_close(), fifo_deinit(), and main().

◆ av_thread_message_queue_send()

int av_thread_message_queue_send ( AVThreadMessageQueue mq,
void *  msg,
unsigned  flags 
)

Send a message on the queue.

Definition at line 156 of file threadmessage.c.

Referenced by fifo_write_packet(), image_available(), and sender_thread().

◆ av_thread_message_queue_recv()

int av_thread_message_queue_recv ( AVThreadMessageQueue mq,
void *  msg,
unsigned  flags 
)

Receive a message from the queue.

Definition at line 172 of file threadmessage.c.

Referenced by android_camera_read_close(), android_camera_read_packet(), fifo_consumer_thread(), and receiver_thread().

◆ av_thread_message_queue_set_err_send()

void av_thread_message_queue_set_err_send ( AVThreadMessageQueue mq,
int  err 
)

Set the sending error code.

If the error code is set to non-zero, av_thread_message_queue_send() will return it immediately. Conventional values, such as AVERROR_EOF or AVERROR(EAGAIN), can be used to cause the sending thread to stop or suspend its operation.

Definition at line 188 of file threadmessage.c.

Referenced by android_camera_read_close(), fifo_consumer_thread(), and receiver_thread().

◆ av_thread_message_queue_set_err_recv()

void av_thread_message_queue_set_err_recv ( AVThreadMessageQueue mq,
int  err 
)

Set the receiving error code.

If the error code is set to non-zero, av_thread_message_queue_recv() will return it immediately when there are no longer available messages. Conventional values, such as AVERROR_EOF or AVERROR(EAGAIN), can be used to cause the receiving thread to stop or suspend its operation.

Definition at line 199 of file threadmessage.c.

Referenced by fifo_write_trailer(), image_available(), and sender_thread().

◆ av_thread_message_queue_set_free_func()

void av_thread_message_queue_set_free_func ( AVThreadMessageQueue mq,
void(*)(void *msg)  free_func 
)

Set the optional free message callback function which will be called if an operation is removing messages from the queue.

Definition at line 83 of file threadmessage.c.

Referenced by fifo_init(), and main().

◆ av_thread_message_queue_nb_elems()

int av_thread_message_queue_nb_elems ( AVThreadMessageQueue mq)

Return the current number of messages in the queue.

Returns
the current number of messages or AVERROR(ENOSYS) if lavu was built without thread support

Definition at line 105 of file threadmessage.c.

Referenced by receiver_thread().

◆ av_thread_message_flush()

void av_thread_message_flush ( AVThreadMessageQueue mq)

Flush the message queue.

This function is mostly equivalent to reading and free-ing every message except that it will be done in a single operation (no lock/unlock between reads).

Definition at line 218 of file threadmessage.c.

Referenced by av_thread_message_queue_free(), fifo_consumer_thread(), receiver_thread(), and sender_thread().