Ringbuffer

Ring buffer implementation More...

Files
file	ringbuffer.h
	spa/utils/ringbuffer.h

Data Structures
struct	spa_ringbuffer
	A ringbuffer type. More...

Macros
#define	SPA_API_RINGBUFFER   static inline
#define	SPA_RINGBUFFER_INIT()

Functions
SPA_API_RINGBUFFER void	spa_ringbuffer_init (struct spa_ringbuffer *rbuf)
	Initialize a spa_ringbuffer with size.
SPA_API_RINGBUFFER void	spa_ringbuffer_set_avail (struct spa_ringbuffer *rbuf, uint32_t size)
	Sets the pointers so that the ringbuffer contains size bytes.
SPA_API_RINGBUFFER int32_t	spa_ringbuffer_get_read_index (struct spa_ringbuffer *rbuf, uint32_t *index)
	Get the read index and available bytes for reading.
SPA_API_RINGBUFFER void	spa_ringbuffer_read_data (struct spa_ringbuffer *rbuf, const void *buffer, uint32_t size, uint32_t offset, void *data, uint32_t len)
	Read len bytes from rbuf starting offset.
SPA_API_RINGBUFFER void	spa_ringbuffer_read_update (struct spa_ringbuffer *rbuf, int32_t index)
	Update the read pointer to index.
SPA_API_RINGBUFFER int32_t	spa_ringbuffer_get_write_index (struct spa_ringbuffer *rbuf, uint32_t *index)
	Get the write index and the number of bytes inside the ringbuffer.
SPA_API_RINGBUFFER void	spa_ringbuffer_write_data (struct spa_ringbuffer *rbuf, void *buffer, uint32_t size, uint32_t offset, const void *data, uint32_t len)
	Write len bytes to buffer starting offset.
SPA_API_RINGBUFFER void	spa_ringbuffer_write_update (struct spa_ringbuffer *rbuf, int32_t index)
	Update the write pointer to index.

Detailed Description

Ring buffer implementation

Macro Definition Documentation

SPA_API_RINGBUFFER

#define SPA_API_RINGBUFFER   static inline

SPA_RINGBUFFER_INIT

#define SPA_RINGBUFFER_INIT

(

)

Value:

((struct spa_ringbuffer) { 0, 0 })

Function Documentation

spa_ringbuffer_init()

SPA_API_RINGBUFFER void spa_ringbuffer_init

(

struct spa_ringbuffer *

rbuf

)

Initialize a spa_ringbuffer with size.

Parameters

rbuf	a spa_ringbuffer

Examples

audio-src-ring.c, and audio-src-ring2.c.

spa_ringbuffer_set_avail()

SPA_API_RINGBUFFER void spa_ringbuffer_set_avail	(	struct spa_ringbuffer *	rbuf,
		uint32_t	size )

Sets the pointers so that the ringbuffer contains size bytes.

Parameters

rbuf	a spa_ringbuffer
size	the target size of rbuf

spa_ringbuffer_get_read_index()

SPA_API_RINGBUFFER int32_t spa_ringbuffer_get_read_index	(	struct spa_ringbuffer *	rbuf,
		uint32_t *	index )

Get the read index and available bytes for reading.

Parameters

rbuf	a spa_ringbuffer
index	the value of readindex, should be taken modulo the size of the ringbuffer memory to get the offset in the ringbuffer memory

Returns

number of available bytes to read. values < 0 mean there was an underrun. values > rbuf->size means there was an overrun.

Examples

audio-src-ring.c, and audio-src-ring2.c.

spa_ringbuffer_read_data()

SPA_API_RINGBUFFER void spa_ringbuffer_read_data	(	struct spa_ringbuffer *	rbuf,
		const void *	buffer,
		uint32_t	size,
		uint32_t	offset,
		void *	data,
		uint32_t	len )

Read len bytes from rbuf starting offset.

offset must be taken modulo size and len should be smaller than size.

Parameters

rbuf	a struct Ringbuffer
buffer	memory to read from
size	the size of buffer
offset	offset in buffer to read from
data	destination memory
len	number of bytes to read

Examples

audio-src-ring.c, and audio-src-ring2.c.

spa_ringbuffer_read_update()

SPA_API_RINGBUFFER void spa_ringbuffer_read_update	(	struct spa_ringbuffer *	rbuf,
		int32_t	index )

Update the read pointer to index.

Parameters

rbuf	a spa_ringbuffer
index	new index

Examples

audio-src-ring.c, and audio-src-ring2.c.

spa_ringbuffer_get_write_index()

SPA_API_RINGBUFFER int32_t spa_ringbuffer_get_write_index	(	struct spa_ringbuffer *	rbuf,
		uint32_t *	index )

Get the write index and the number of bytes inside the ringbuffer.

Parameters

rbuf	a spa_ringbuffer
index	the value of writeindex, should be taken modulo the size of the ringbuffer memory to get the offset in the ringbuffer memory

Returns

the fill level of rbuf. values < 0 mean there was an underrun. values > rbuf->size means there was an overrun. Subtract from the buffer size to get the number of bytes available for writing.

Examples

audio-src-ring.c, and audio-src-ring2.c.

spa_ringbuffer_write_data()

SPA_API_RINGBUFFER void spa_ringbuffer_write_data	(	struct spa_ringbuffer *	rbuf,
		void *	buffer,
		uint32_t	size,
		uint32_t	offset,
		const void *	data,
		uint32_t	len )

Write len bytes to buffer starting offset.

offset must be taken modulo size and len should be smaller than size.

Parameters

rbuf	a spa_ringbuffer
buffer	memory to write to
size	the size of buffer
offset	offset in buffer to write to
data	source memory
len	number of bytes to write

Examples

audio-src-ring2.c.

spa_ringbuffer_write_update()

SPA_API_RINGBUFFER void spa_ringbuffer_write_update	(	struct spa_ringbuffer *	rbuf,
		int32_t	index )

Update the write pointer to index.

Parameters

rbuf	a spa_ringbuffer
index	new index

Examples

audio-src-ring.c, and audio-src-ring2.c.