gp_cbuffer.h File Reference

Circular buffer indexing and iterators. More...

#include <stddef.h>

Go to the source code of this file.

Data Structures
struct	gp_cbuffer
	A circular buffer indexes. More...
struct	gp_cbuffer_iter
	An interator for loops over the circular buffer. More...

Macros
#define	GP_CBUFFER_FOREACH(self, iter)
	Loops over all elements in the circular buffer.
#define	GP_CBUFFER_FORRANGE(self, iter, skip, count)
	Loops over a range of elements in the circular buffer.
#define	GP_CBUFFER_FOREACH_REV(self, iter)
	Loops backwards over all elements in the circular buffer.

Typedefs
typedef struct gp_cbuffer	gp_cbuffer
	A circular buffer indexes.
typedef struct gp_cbuffer_iter	gp_cbuffer_iter
	An interator for loops over the circular buffer.

Functions
static void	gp_cbuffer_init (gp_cbuffer *self, size_t size)
	Initializes circular buffer.
static size_t	gp_cbuffer_append (gp_cbuffer *self)
	Appends into circular buffer.
static size_t	gp_cbuffer_next (gp_cbuffer *self, size_t idx)
	Returns next position in the circular buffer.
static size_t	gp_cbuffer_prev (gp_cbuffer *self, size_t idx)
	Returns previous position in the circular buffer.
static size_t	gp_cbuffer_used (gp_cbuffer *self)
	Returns number of used positions in the circular buffer.
static size_t	gp_cbuffer_first (gp_cbuffer *self)
	Returns index to the first element in buffer.
static size_t	gp_cbuffer_last (gp_cbuffer *self)
	Returns index to the last element in buffer.

Detailed Description

Circular buffer indexing and iterators.

Definition in file gp_cbuffer.h.

Macro Definition Documentation

GP_CBUFFER_FOREACH

#define GP_CBUFFER_FOREACH	(		self,
			iter
	)

Value:

        for ((iter)->idx = gp_cbuffer_first(self), (iter)->cnt = 0; \
             (iter)->cnt < (self)->used; \
             (iter)->idx = gp_cbuffer_next(self, (iter)->idx), (iter)->cnt++)

Loops over all elements in the circular buffer.

Parameters

self	A circular buffer.
iter	A circular buffer iterator variable.

Definition at line 151 of file gp_cbuffer.h.

GP_CBUFFER_FOREACH_REV

#define GP_CBUFFER_FOREACH_REV	(		self,
			iter
	)

Value:

        for ((iter)->idx = gp_cbuffer_last(self), (iter)->cnt = 0; \
             (iter)->cnt < (self)->used; \
             (iter)->idx = gp_cbuffer_prev(self, (iter)->idx), (iter)->cnt++)

Loops backwards over all elements in the circular buffer.

Parameters

self	A circular buffer.
iter	A circular buffer iterator variable.

Definition at line 176 of file gp_cbuffer.h.

GP_CBUFFER_FORRANGE

#define GP_CBUFFER_FORRANGE	(		self,
			iter,
			skip,
			count
	)

Value:

        if ((self)->used > skip) \
                for ((iter)->idx = (gp_cbuffer_first(self) + skip) % (self)->size, (iter)->cnt = 0; \
                     (iter)->cnt < GP_MIN((self)->used - skip, count); \
                     (iter)->idx = gp_cbuffer_next(self, (iter)->idx), (iter)->cnt++)

Loops over a range of elements in the circular buffer.

Parameters

self	A circular buffer.
iter	A circular buffer iterator variable.
skip	How many element should we skip at the start.
count	How many element should we iterater over.

Definition at line 164 of file gp_cbuffer.h.

Function Documentation

gp_cbuffer_append()

static size_t gp_cbuffer_append ( gp_cbuffer *  self )

inlinestatic

Appends into circular buffer.

Only index into the buffer array is returned, any old data has to be freed by the user of this API.

Parameters

self	A circular buffer.

Returns

An index for the buffer to append.

Definition at line 50 of file gp_cbuffer.h.

References gp_cbuffer::last, gp_cbuffer::size, and gp_cbuffer::used.

gp_cbuffer_first()

static size_t gp_cbuffer_first ( gp_cbuffer *  self )

inlinestatic

Returns index to the first element in buffer.

Returns invalid data for empty buffer, make sure buffer is not empty with gp_buffer_used() before using this function.

Parameters

self	A circular buffer.

Returns

First used position in the buffer.

Definition at line 109 of file gp_cbuffer.h.

References gp_cbuffer::last, gp_cbuffer::size, and gp_cbuffer::used.

gp_cbuffer_init()

static void gp_cbuffer_init ( gp_cbuffer *  self, size_t  size  )

inlinestatic

Initializes circular buffer.

Parameters

self	A circular buffer to be initialized.
size	Size of the buffer.

Definition at line 34 of file gp_cbuffer.h.

References gp_cbuffer::last, gp_cbuffer::size, and gp_cbuffer::used.

gp_cbuffer_last()

static size_t gp_cbuffer_last ( gp_cbuffer *  self )

inlinestatic

Returns index to the last element in buffer.

Returns invalid data for empty buffer, make sure buffer is not empty with gp_buffer_used() before using this function.

Parameters

self	A circular buffer.

Returns

Last used position in the buffer.

Definition at line 130 of file gp_cbuffer.h.

References gp_cbuffer_prev(), and gp_cbuffer::last.

gp_cbuffer_next()

static size_t gp_cbuffer_next ( gp_cbuffer *  self, size_t  idx  )

inlinestatic

Returns next position in the circular buffer.

Parameters

self	A circular buffer.
idx	A current position in the buffer.

Returns

Next position in the buffer.

Definition at line 69 of file gp_cbuffer.h.

References gp_cbuffer::size.

gp_cbuffer_prev()

static size_t gp_cbuffer_prev ( gp_cbuffer *  self, size_t  idx  )

inlinestatic

Returns previous position in the circular buffer.

Parameters

self	A circular buffer.
idx	A current position in the buffer.

Returns

Previous position in the buffer.

Definition at line 81 of file gp_cbuffer.h.

References gp_cbuffer::size.

Referenced by gp_cbuffer_last().

gp_cbuffer_used()

static size_t gp_cbuffer_used ( gp_cbuffer *  self )

inlinestatic

Returns number of used positions in the circular buffer.

Parameters

self	A circular buffer.

Returns

Number of used postions in the buffer.

Definition at line 95 of file gp_cbuffer.h.

References gp_cbuffer::used.