Application sources

Element injecting application data into a pipeline. More...

Files
file	mpipe_app_src.h
	Application source element.

Data Structures
struct	mpipe_app_src
	Application source element structure. More...

Enumerations
enum	{ MPIPE_PROP_BASE_APP_SRC_CAPS = MPIPE_PROP_SRC_LAST }
	Application source property identifiers. More...

Functions
int	mpipe_app_src_init (struct mpipe_app_src *app_src, uint8_t id)
	Initialize an application source element.
int	mpipe_app_src_alloc (struct mpipe_app_src *app_src, uint32_t size, k_timeout_t timeout, struct net_buf **buf)
	Take a buffer of the element's pool to fill in place.
int	mpipe_app_src_push_buf (struct mpipe_app_src *app_src, struct net_buf *buf, uint32_t size, k_timeout_t timeout)
	Queue a filled buffer into the pipeline.
int	mpipe_app_src_push (struct mpipe_app_src *app_src, const void *data, uint32_t size, k_timeout_t timeout)
	Push one payload into the pipeline, by copy.
int	mpipe_app_src_eos (struct mpipe_app_src *app_src, k_timeout_t timeout)
	Declare end of stream.

Detailed Description

Element injecting application data into a pipeline.

The application boundary on the producing side. Payloads either travel by copy, with mpipe_app_src_push, or in place: mpipe_app_src_alloc hands out a buffer of the element's pool for the application to fill, and mpipe_app_src_push_buf queues it.

Push once the pipeline is at least PAUSED: whatever was queued while READY is discarded when the pipeline starts. End of stream is declared with mpipe_app_src_eos; alternatively MPIPE_PROP_SRC_NUM_BUFS ends the stream after a number of buffers.

Enumeration Type Documentation

anonymous enum

anonymous enum

#include <mpipe_app_src.h>

Application source property identifiers.

Enumerator
MPIPE_PROP_BASE_APP_SRC_CAPS	Capability of the produced stream, a const struct mpipe_structure pointer, copied. It is what negotiation offers downstream; what the application pushes must match it, the element cannot check. Until it is set the element offers a capability constraining nothing.

Function Documentation

mpipe_app_src_alloc()

int mpipe_app_src_alloc	(	struct mpipe_app_src *	app_src,
		uint32_t	size,
		k_timeout_t	timeout,
		struct net_buf **	buf )

#include <mpipe_app_src.h>

Take a buffer of the element's pool to fill in place.

The buffer holds up to CONFIG_MPIPE_BASE_APP_SRC_BUF_SZ bytes. The application writes its payload into the buffer data and hands the buffer to mpipe_app_src_push_buf, or releases it with net_buf_unref() if it changes its mind.

Parameters

app_src	The application source
size	Number of payload bytes the buffer must hold
timeout	How long to wait for a free buffer
buf	Filled with the buffer

Return values

0	Success
-EINVAL	Bad arguments, or size above the buffer size
-ENOBUFS	No buffer became free within timeout

mpipe_app_src_eos()

int mpipe_app_src_eos	(	struct mpipe_app_src *	app_src,
		k_timeout_t	timeout )

#include <mpipe_app_src.h>

Declare end of stream.

Buffers pushed before this call are still delivered; the pipeline then receives EOS.

Parameters

app_src	The application source
timeout	How long to wait for a queue slot

Return values

0	Success
-EINVAL	app_src is NULL
-EAGAIN	The queue stayed full within timeout

mpipe_app_src_init()

int mpipe_app_src_init	(	struct mpipe_app_src *	app_src,
		uint8_t	id )

#include <mpipe_app_src.h>

Initialize an application source element.

Parameters

app_src	Pointer to the element to initialize.
id	Unique element identifier.

Returns

0 on success, negative errno otherwise.

mpipe_app_src_push()

int mpipe_app_src_push	(	struct mpipe_app_src *	app_src,
		const void *	data,
		uint32_t	size,
		k_timeout_t	timeout )

#include <mpipe_app_src.h>

Push one payload into the pipeline, by copy.

Takes a buffer, copies size bytes into it and queues it: the two waits may each last up to timeout.

Parameters

app_src	The application source
data	Payload bytes
size	Number of bytes, bounded by CONFIG_MPIPE_BASE_APP_SRC_BUF_SZ
timeout	How long to wait for a free buffer, and for a queue slot

Return values

0	Success
-EINVAL	Bad arguments
-ENOBUFS	No buffer became free within timeout
-EAGAIN	The queue stayed full within timeout

mpipe_app_src_push_buf()

int mpipe_app_src_push_buf	(	struct mpipe_app_src *	app_src,
		struct net_buf *	buf,
		uint32_t	size,
		k_timeout_t	timeout )

#include <mpipe_app_src.h>

Queue a filled buffer into the pipeline.

The buffer comes from mpipe_app_src_alloc. On success the pipeline owns it; on failure it stays the caller's, to retry or release.

Parameters

app_src	The application source
buf	The buffer to queue
size	Number of valid payload bytes in the buffer
timeout	How long to wait for a queue slot

Return values

0	Success
-EINVAL	Bad arguments, or size above what the buffer holds
-EAGAIN	The queue stayed full within timeout