FIFO stream

In-memory anonymous pipe. More...

Collaboration diagram for FIFO stream:

Typedefs
typedef struct vlc_stream_fifo	vlc_stream_fifo_t

Functions
vlc_stream_fifo_t *	vlc_stream_fifo_New (vlc_object_t *parent, stream_t **reader)
	Creates a FIFO stream. More...
int	vlc_stream_fifo_Queue (vlc_stream_fifo_t *s, block_t *block)
	Writes a block to a FIFO stream. More...
ssize_t	vlc_stream_fifo_Write (vlc_stream_fifo_t *s, const void *buf, size_t len)
	Writes data to a FIFO stream. More...
void	vlc_stream_fifo_Close (vlc_stream_fifo_t *s)
	Terminates a FIFO stream. More...

Detailed Description

In-memory anonymous pipe.

Typedef Documentation

vlc_stream_fifo_t

typedef struct vlc_stream_fifo vlc_stream_fifo_t

Function Documentation

vlc_stream_fifo_Close()

void vlc_stream_fifo_Close

(

vlc_stream_fifo_t *

s

)

Terminates a FIFO stream.

Marks the end of the FIFO stream and releases any underlying resources.

Parameters

s	FIFO stream created by vlc_stream_fifo_New()

References block_FifoRelease(), vlc_stream_fifo::eof, vlc_stream_fifo::fifo, vlc_fifo_Lock(), vlc_fifo_Signal(), and vlc_fifo_Unlock().

Referenced by vlc_demux_chained_Delete(), and vlc_demux_chained_New().

vlc_stream_fifo_New()

vlc_stream_fifo_t* vlc_stream_fifo_New	(	vlc_object_t *	parent,
		stream_t **	reader
	)

Creates a FIFO stream.

Creates a non-seekable byte stream object whose byte stream is generated by another thread in the process. This is the LibVLC equivalent of an anonymous pipe/FIFO.

On the reader side, the normal stream functions are used, e.g. vlc_stream_Read() and vlc_stream_Delete().

The created stream object is automatically destroyed when both the reader and the writer sides have been closed, with vlc_stream_Delete() and vlc_stream_fifo_Close() respectively.

Parameters

parent	parent VLC object for the stream
reader	location to store read side stream pointer [OUT]

Returns

a FIFO stream object or NULL on memory error.

References block_FifoNew(), block_FifoRelease(), vlc_stream_fifo::eof, vlc_stream_fifo::fifo, stream_t::pf_block, stream_t::pf_control, stream_t::pf_seek, unlikely, vlc_stream_CustomNew(), vlc_stream_fifo_Block(), vlc_stream_fifo_Control(), vlc_stream_fifo_Destroy(), vlc_stream_Private(), and vlc_stream_fifo_private::writer.

Referenced by vlc_demux_chained_New().

vlc_stream_fifo_Queue()

int vlc_stream_fifo_Queue	(	vlc_stream_fifo_t *	s,
		block_t *	block
	)

Writes a block to a FIFO stream.

Parameters

s	FIFO stream created by vlc_stream_fifo_New()
block	data block to write to the stream

Returns

0 on success. -1 if the reader end has already been closed (errno is then set to EPIPE, and the block is deleted).

Bug:

No congestion control is performed. If the reader end is not keeping up with the writer end, buffers will accumulate in memory.

References block_Release(), vlc_stream_fifo::eof, vlc_stream_fifo::fifo, likely, unlikely, vlc_fifo_Lock(), vlc_fifo_QueueUnlocked(), and vlc_fifo_Unlock().

Referenced by vlc_demux_chained_Send(), and vlc_stream_fifo_Write().

vlc_stream_fifo_Write()

ssize_t vlc_stream_fifo_Write	(	vlc_stream_fifo_t *	s,
		const void *	buf,
		size_t	len
	)

Writes data to a FIFO stream.

This is a convenience helper for vlc_stream_fifo_Queue().

Parameters

s	FIFO stream created by vlc_stream_fifo_New()
buf	start address of data to write
len	length of data to write in bytes

Returns

len on success, or -1 on error (errno is set accordingly)

References block_Alloc(), block_t::p_buffer, unlikely, and vlc_stream_fifo_Queue().