bitfields operations on bitfields of arbitrary length More...

Detailed Description

bitfields operations on bitfields of arbitrary length

Note: Code taken mostly from Stackoverflow, User Christoph

Author: Oliver Hahm olive.nosp@m.r.ha.nosp@m.hm@in.nosp@m.ria..nosp@m.fr

Definition in file bitfield.h.

#include <stdint.h>
#include <stdbool.h>
#include <stddef.h>

Include dependency graph for bitfield.h:

This graph shows which files directly or indirectly include this file:

Go to the source code of this file.

#define	BITFIELD(NAME, SIZE) uint8_t NAME[((SIZE) + 7) / 8]
	Declare a bitfield of a given size. More...

static void	bf_set (uint8_t field[], size_t idx)
	Set the bit to 1. More...

static void	bf_unset (uint8_t field[], size_t idx)
	Clear the bit. More...

static void	bf_toggle (uint8_t field[], size_t idx)
	Toggle the bit. More...

static bool	bf_isset (uint8_t field[], size_t idx)
	Check if the bet is set. More...

int	bf_get_unset (uint8_t field[], int size)
	Atomically get the number of an unset bit and set it. More...

Macro Definition Documentation

◆ BITFIELD

#define BITFIELD	(	NAME,
		SIZE
	)	uint8_t NAME[((SIZE) + 7) / 8]

Declare a bitfield of a given size.

Note: SIZE should be a constant expression. This avoids variable length arrays.

Definition at line 46 of file bitfield.h.

Function Documentation

◆ bf_get_unset()

int bf_get_unset	(	uint8_t	field[],
		int	size
	)

Atomically get the number of an unset bit and set it.

This function can be used to record e.g., empty entries in an array.

Parameters

[in,out]	field	The bitfield
[in]	size	The size of the bitfield

Returns: number of bit that was set; -1 if no bit was unset

◆ bf_isset()

static bool bf_isset	(	uint8_t	field[],
		size_t	idx
	)

inlinestatic

Check if the bet is set.

Parameters

[in,out]	field	The bitfield
[in]	idx	The number of the bit to check

Definition at line 87 of file bitfield.h.

◆ bf_set()

static void bf_set	(	uint8_t	field[],
		size_t	idx
	)

inlinestatic

Set the bit to 1.

Parameters

[in,out]	field	The bitfield
[in]	idx	The number of the bit to set

Definition at line 54 of file bitfield.h.

◆ bf_toggle()

static void bf_toggle	(	uint8_t	field[],
		size_t	idx
	)

inlinestatic

Toggle the bit.

Parameters

[in,out]	field	The bitfield
[in]	idx	The number of the bit to toggle

Definition at line 76 of file bitfield.h.

◆ bf_unset()

static void bf_unset	(	uint8_t	field[],
		size_t	idx
	)

inlinestatic

Clear the bit.

Parameters

[in,out]	field	The bitfield
[in]	idx	The number of the bit to clear

Definition at line 65 of file bitfield.h.