util.h File Reference

Misc utilities. More...

#include <zephyr/sys/util_macro.h>
#include <zephyr/toolchain.h>
#include <stdbool.h>
#include <zephyr/types.h>
#include <stddef.h>
#include <stdint.h>
#include <zephyr/sys/time_units.h>

Go to the source code of this file.

Macros
#define	NUM_BITS(t)   (sizeof(t) * 8)
	Number of bits that make up a type.
#define	POINTER_TO_UINT(x)   ((uintptr_t) (x))
	Cast x, a pointer, to an unsigned integer.
#define	UINT_TO_POINTER(x)   ((void *) (uintptr_t) (x))
	Cast x, an unsigned integer, to a void*.
#define	POINTER_TO_INT(x)   ((intptr_t) (x))
	Cast x, a pointer, to a signed integer.
#define	INT_TO_POINTER(x)   ((void *) (intptr_t) (x))
	Cast x, a signed integer, to a void*.
#define	BITS_PER_LONG   (__CHAR_BIT__ * __SIZEOF_LONG__)
	Number of bits in a long int.
#define	BITS_PER_LONG_LONG   (__CHAR_BIT__ * __SIZEOF_LONG_LONG__)
	Number of bits in a long long int.
#define	GENMASK(h, l)    (((~0UL) - (1UL << (l)) + 1) & (~0UL >> (BITS_PER_LONG - 1 - (h))))
	Create a contiguous bitmask starting at bit position l and ending at position h.
#define	GENMASK64(h, l)    (((~0ULL) - (1ULL << (l)) + 1) & (~0ULL >> (BITS_PER_LONG_LONG - 1 - (h))))
	Create a contiguous 64-bit bitmask starting at bit position l and ending at position h.
#define	LSB_GET(value)   ((value) & -(value))
	Extract the Least Significant Bit from value.
#define	FIELD_GET(mask, value)   (((value) & (mask)) / LSB_GET(mask))
	Extract a bitfield element from value corresponding to the field mask mask.
#define	FIELD_PREP(mask, value)   (((value) * LSB_GET(mask)) & (mask))
	Prepare a bitfield element using value with mask representing its field position and width.
#define	ZERO_OR_COMPILE_ERROR(cond)   ((int) sizeof(char[1 - 2 * !(cond)]) - 1)
	0 if cond is true-ish; causes a compile error otherwise.
#define	IS_ARRAY(array)
	Zero if array has an array type, a compile error otherwise.
#define	ARRAY_SIZE(array)    ((size_t) (IS_ARRAY(array) + (sizeof(array) / sizeof((array)[0]))))
	Number of elements in the given array.
#define	IS_ARRAY_ELEMENT(array, ptr)
	Whether ptr is an element of array.
#define	ARRAY_INDEX(array, ptr)
	Index of ptr within array.
#define	PART_OF_ARRAY(array, ptr)
	Check if a pointer ptr lies within array.
#define	ARRAY_INDEX_FLOOR(array, ptr)
	Array-index of ptr within array, rounded down.
#define	SAME_TYPE(a, b)   __builtin_types_compatible_p(__typeof__(a), __typeof__(b))
	Validate if two entities have a compatible type.
#define	CONTAINER_OF_VALIDATE(ptr, type, field)
	Validate CONTAINER_OF parameters, only applies to C mode.
#define	CONTAINER_OF(ptr, type, field)
	Get a pointer to a structure containing the element.
#define	ROUND_UP(x, align)
	Value of x rounded up to the next multiple of align.
#define	ROUND_DOWN(x, align)    (((unsigned long)(x) / (unsigned long)(align)) * (unsigned long)(align))
	Value of x rounded down to the previous multiple of align.
#define	WB_UP(x)   ROUND_UP(x, sizeof(void *))
	Value of x rounded up to the next word boundary.
#define	WB_DN(x)   ROUND_DOWN(x, sizeof(void *))
	Value of x rounded down to the previous word boundary.
#define	DIV_ROUND_UP(n, d)   (((n) + (d) - 1) / (d))
	Divide and round up.
#define	DIV_ROUND_CLOSEST(n, d)
	Divide and round to the nearest integer.
#define	ceiling_fraction(numerator, divider)
	Ceiling function applied to numerator / divider as a fraction.
#define	MAX(a, b)   (((a) > (b)) ? (a) : (b))
	Obtain the maximum of two values.
#define	MIN(a, b)   (((a) < (b)) ? (a) : (b))
	Obtain the minimum of two values.
#define	CLAMP(val, low, high)   (((val) <= (low)) ? (low) : MIN(val, high))
	Clamp a value to a given range.
#define	IN_RANGE(val, min, max)   ((val) >= (min) && (val) <= (max))
	Checks if a value is within range.
#define	LOG2(x)   ((x) < 1 ? -1 : __z_log2(x))
	Compute log2(x)
#define	LOG2CEIL(x)   ((x) < 1 ? 0 : __z_log2((x)-1) + 1)
	Compute ceil(log2(x))
#define	NHPOT(x)   ((x) < 1 ? 1 : ((x) > (1ULL<<63) ? 0 : 1ULL << LOG2CEIL(x)))
	Compute next highest power of two.
#define	KB(x)   ((x) << 10)
	Number of bytes in x kibibytes.
#define	MB(x)   (KB(x) << 10)
	Number of bytes in x mebibytes.
#define	GB(x)   (MB(x) << 10)
	Number of bytes in x gibibytes.
#define	KHZ(x)   ((x) * 1000)
	Number of Hz in x kHz.
#define	MHZ(x)   (KHZ(x) * 1000)
	Number of Hz in x MHz.
#define	WAIT_FOR(expr, timeout, delay_stmt)
	Wait for an expression to return true with a timeout.

Functions
static bool	is_power_of_two (unsigned int x)
	Is x a power of two?
static int64_t	arithmetic_shift_right (int64_t value, uint8_t shift)
	Arithmetic shift right.
static void	bytecpy (void *dst, const void *src, size_t size)
	byte by byte memcpy.
static void	byteswp (void *a, void *b, size_t size)
	byte by byte swap.
int	char2hex (char c, uint8_t *x)
	Convert a single character into a hexadecimal nibble.
int	hex2char (uint8_t x, char *c)
	Convert a single hexadecimal nibble into a character.
size_t	bin2hex (const uint8_t *buf, size_t buflen, char *hex, size_t hexlen)
	Convert a binary array into string representation.
size_t	hex2bin (const char *hex, size_t hexlen, uint8_t *buf, size_t buflen)
	Convert a hexadecimal string into a binary array.
static uint8_t	bcd2bin (uint8_t bcd)
	Convert a binary coded decimal (BCD 8421) value to binary.
static uint8_t	bin2bcd (uint8_t bin)
	Convert a binary value to binary coded decimal (BCD 8421).
uint8_t	u8_to_dec (char *buf, uint8_t buflen, uint8_t value)
	Convert a uint8_t into a decimal string representation.
char *	utf8_trunc (char *utf8_str)
	Properly truncate a NULL-terminated UTF-8 string.
char *	utf8_lcpy (char *dst, const char *src, size_t n)
	Copies a UTF-8 encoded string from src to dst.

Detailed Description

Misc utilities.

Misc utilities usable by the kernel and application code.

Macro Definition Documentation

NUM_BITS

#define NUM_BITS

(

t

)

(sizeof(t) * 8)

Number of bits that make up a type.