Ring Buffer

Collaboration diagram for Ring Buffer:

Modules
	Contiguous Ring Buffer Access
	Functions for contiguous access to ring buffer data.
	Discontiguous Ring Buffer Access
	Functions for discontiguous access to ring buffer data.

Data Structures
struct	ring_buf
	Ring buffer instance. More...

Macros
#define	RING_BUF_DEFINE_STATIC(_name_, _size_)
	Defines a static ring buffer.

Functions
static ring_buf_size_t	ring_buf_used_space (const struct ring_buf *buf)
	Calculates used space in the ring buffer.
static bool	ring_buf_is_empty (const struct ring_buf *buf)
	Checks if the ring buffer is empty.
static ring_buf_size_t	ring_buf_free_space (const struct ring_buf *buf)
	Calculates free space in the ring buffer.
static bool	ring_buf_is_full (const struct ring_buf *buf)
	Checks if the ring buffer is full.
void	ring_buf_reset (struct ring_buf *buf, ring_buf_ptrdiff_t base)
	Resets a ring buffer.

Detailed Description

Macro Definition Documentation

RING_BUF_DEFINE_STATIC

#define RING_BUF_DEFINE_STATIC	(		_name_,
			_size_
	)

Value:

  static uint8_t _ring_buf_space_##_name_[_size_];                             \
  static struct ring_buf _name_ = {.space = _ring_buf_space_##_name_,          \
                                   .size = _size_}

Defines a static ring buffer.

This macro creates a ring buffer with the specified name and size. It statically allocates the ring buffer's storage space as an array of bytes.

It correctly initialises the ring buffer structure with a pointer to the allocated space and sets the size. The put and get zones are initialised to zero by default. This assumes that the compiler will zero-initialise static storage, i.e. allocated storage in the Blank Static Storage section. There is not need to explicitly reset the ring buffer before use.

Parameters

_name_	Name of the ring buffer.
_size_	Size of the ring buffer.

Definition at line 351 of file ring_buf.h.

Function Documentation

ring_buf_free_space()

static ring_buf_size_t ring_buf_free_space ( const struct ring_buf *  buf )

inlinestatic

Calculates free space in the ring buffer.

Computes the number of bytes currently available for use in the ring buffer.

Parameters

buf	Ring buffer.

Returns

Number of free bytes.

Definition at line 183 of file ring_buf.h.

ring_buf_is_empty()

static bool ring_buf_is_empty ( const struct ring_buf *  buf )

inlinestatic

Checks if the ring buffer is empty.

Determines whether the ring buffer has no used space. A ring buffer is considered empty when the used space is zero.

Parameters

buf	Ring buffer.

Return values

true	if the buffer is empty.
false	otherwise.

Definition at line 172 of file ring_buf.h.

ring_buf_is_full()

static bool ring_buf_is_full ( const struct ring_buf *  buf )

inlinestatic

Checks if the ring buffer is full.

Determines whether the ring buffer has no free space. A ring buffer is considered full when the free space is zero.

Parameters

buf	Ring buffer.

Return values

true	if the buffer is full.
false	if not full.

Definition at line 195 of file ring_buf.h.

ring_buf_reset()

void ring_buf_reset	(	struct ring_buf *	buf,
		ring_buf_ptrdiff_t	base
	)

Resets a ring buffer.

Resets both put and get zones to the specified base index. The base index typically starts at zero but can be set to any value.

Parameters

buf	Ring buffer.
base	Base index for both put and get zones.

Definition at line 96 of file ring_buf.c.

ring_buf_used_space()

static ring_buf_size_t ring_buf_used_space ( const struct ring_buf *  buf )

inlinestatic

Calculates used space in the ring buffer.

Computes the number of bytes currently used in the ring buffer.

Parameters

buf	Ring buffer.

Returns

Number of used bytes.

Definition at line 160 of file ring_buf.h.