| 
    Zephyr Project API
    3.4.0
    
   A Scalable Open Source RTOS 
   | 
 
Macros | |
| #define | POINTER_TO_UINT(x) ((uintptr_t) (x)) | 
Cast x, a pointer, to an unsigned integer.  More... | |
| #define | UINT_TO_POINTER(x) ((void *) (uintptr_t) (x)) | 
Cast x, an unsigned integer, to a void*.  More... | |
| #define | POINTER_TO_INT(x) ((intptr_t) (x)) | 
Cast x, a pointer, to a signed integer.  More... | |
| #define | INT_TO_POINTER(x) ((void *) (intptr_t) (x)) | 
Cast x, a signed integer, to a void*.  More... | |
| #define | BITS_PER_LONG (__CHAR_BIT__ * __SIZEOF_LONG__) | 
| #define | BITS_PER_LONG_LONG (__CHAR_BIT__ * __SIZEOF_LONG_LONG__) | 
| #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.  More... | |
| #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.  More... | |
| #define | LSB_GET(value) ((value) & -(value)) | 
Extract the Least Significant Bit from value.  More... | |
| #define | FIELD_GET(mask, value) (((value) & (mask)) / LSB_GET(mask)) | 
Extract a bitfield element from value corresponding to the field mask mask.  More... | |
| #define | FIELD_PREP(mask, value) (((value) * LSB_GET(mask)) & (mask)) | 
Prepare a bitfield element using value with mask representing its field position and width. The result should be combined with other fields using a logical OR.  More... | |
| #define | ZERO_OR_COMPILE_ERROR(cond) ((int) sizeof(char[1 - 2 * !(cond)]) - 1) | 
0 if cond is true-ish; causes a compile error otherwise.  More... | |
| #define | IS_ARRAY(array) | 
Zero if array has an array type, a compile error otherwise.  More... | |
| #define | ARRAY_SIZE(array) ((size_t) (IS_ARRAY(array) + (sizeof(array) / sizeof((array)[0])))) | 
Number of elements in the given array.  More... | |
| #define | IS_ARRAY_ELEMENT(array, ptr) | 
Whether ptr is an element of array.  More... | |
| #define | ARRAY_INDEX(array, ptr) | 
Index of ptr within array.  More... | |
| #define | PART_OF_ARRAY(array, ptr) | 
Check if a pointer ptr lies within array.  More... | |
| #define | ARRAY_INDEX_FLOOR(array, ptr) | 
Array-index of ptr within array, rounded down.  More... | |
| #define | CONTAINER_OF(ptr, type, field) ((type *)(((char *)(ptr)) - offsetof(type, field))) | 
| Get a pointer to a structure containing the element.  More... | |
| #define | ROUND_UP(x, align) | 
Value of x rounded up to the next multiple of align, which must be a power of 2.  More... | |
| #define | ROUND_DOWN(x, align) ((unsigned long)(x) & ~((unsigned long)(align) - 1)) | 
Value of x rounded down to the previous multiple of align, which must be a power of 2.  More... | |
| #define | WB_UP(x) ROUND_UP(x, sizeof(void *)) | 
Value of x rounded up to the next word boundary.  More... | |
| #define | WB_DN(x) ROUND_DOWN(x, sizeof(void *)) | 
Value of x rounded down to the previous word boundary.  More... | |
| #define | DIV_ROUND_UP(n, d) (((n) + (d) - 1) / (d)) | 
| Divide and round up.  More... | |
| #define | ceiling_fraction(numerator, divider) | 
Ceiling function applied to numerator / divider as a fraction.  More... | |
| #define | MAX(a, b) (((a) > (b)) ? (a) : (b)) | 
| Obtain the maximum of two values.  More... | |
| #define | MIN(a, b) (((a) < (b)) ? (a) : (b)) | 
| Obtain the minimum of two values.  More... | |
| #define | CLAMP(val, low, high) (((val) <= (low)) ? (low) : MIN(val, high)) | 
| Clamp a value to a given range.  More... | |
| #define | IN_RANGE(val, min, max) ((val) >= (min) && (val) <= (max)) | 
| Checks if a value is within range.  More... | |
| #define | LOG2(x) ((x) < 1 ? -1 : __z_log2(x)) | 
| Compute log2(x)  More... | |
| #define | LOG2CEIL(x) ((x) < 1 ? 0 : __z_log2((x)-1) + 1) | 
| Compute ceil(log2(x))  More... | |
| #define | NHPOT(x) ((x) < 1 ? 1 : ((x) > (1ULL<<63) ? 0 : 1ULL << LOG2CEIL(x))) | 
| Compute next highest power of two.  More... | |
| #define | KB(x) ((x) << 10) | 
Number of bytes in x kibibytes.  More... | |
| #define | MB(x) (KB(x) << 10) | 
Number of bytes in x mebibytes.  More... | |
| #define | GB(x) (MB(x) << 10) | 
Number of bytes in x gibibytes.  More... | |
| #define | KHZ(x) ((x) * 1000) | 
Number of Hz in x kHz.  More... | |
| #define | MHZ(x) (KHZ(x) * 1000) | 
Number of Hz in x MHz.  More... | |
| #define | WAIT_FOR(expr, timeout, delay_stmt) | 
| Wait for an expression to return true with a timeout.  More... | |
| #define | BIT(n) (1UL << (n)) | 
Unsigned integer with bit position n set (signed in assembly language).  More... | |
| #define | BIT64(_n) (1ULL << (_n)) | 
64-bit unsigned integer with bit position _n set.  More... | |
| #define | WRITE_BIT(var, bit, set) ((var) = (set) ? ((var) | BIT(bit)) : ((var) & ~BIT(bit))) | 
| Set or clear a bit depending on a boolean value.  More... | |
| #define | BIT_MASK(n) (BIT(n) - 1UL) | 
Bit mask with bits 0 through n-1 (inclusive) set, or 0 if n is 0.  More... | |
| #define | BIT64_MASK(n) (BIT64(n) - 1ULL) | 
64-bit bit mask with bits 0 through n-1 (inclusive) set, or 0 if n is 0.  More... | |
| #define | IS_POWER_OF_TWO(x) (((x) != 0U) && (((x) & ((x) - 1U)) == 0U)) | 
Check if a x is a power of two.  More... | |
| #define | IS_SHIFTED_BIT_MASK(m, s) (!(((m) >> (s)) & (((m) >> (s)) + 1U))) | 
| Check if bits are set continuously from the specified bit.  More... | |
| #define | IS_BIT_MASK(m) IS_SHIFTED_BIT_MASK(m, 0) | 
| Check if bits are set continuously from the LSB.  More... | |
| #define | IS_ENABLED(config_macro) Z_IS_ENABLED1(config_macro) | 
| Check for macro definition in compiler-visible expressions.  More... | |
| #define | COND_CODE_1(_flag, _if_1_code, _else_code) Z_COND_CODE_1(_flag, _if_1_code, _else_code) | 
Insert code depending on whether _flag expands to 1 or not.  More... | |
| #define | COND_CODE_0(_flag, _if_0_code, _else_code) Z_COND_CODE_0(_flag, _if_0_code, _else_code) | 
Like COND_CODE_1() except tests if _flag is 0.  More... | |
| #define | IF_ENABLED(_flag, _code) COND_CODE_1(_flag, _code, ()) | 
Insert code if _flag is defined and equals 1.  More... | |
| #define | IS_EMPTY(...) Z_IS_EMPTY_(__VA_ARGS__) | 
| Check if a macro has a replacement expression.  More... | |
| #define | IS_EQ(a, b) Z_IS_EQ(a, b) | 
Like a == b, but does evaluation and short-circuiting at C preprocessor time.  More... | |
| #define | LIST_DROP_EMPTY(...) Z_LIST_DROP_FIRST(FOR_EACH(Z_LIST_NO_EMPTIES, (), __VA_ARGS__)) | 
| Remove empty arguments from list.  More... | |
| #define | EMPTY | 
| Macro with an empty expansion.  More... | |
| #define | IDENTITY(V) V | 
| Macro that expands to its argument.  More... | |
| #define | GET_ARG_N(N, ...) Z_GET_ARG_##N(__VA_ARGS__) | 
| Get nth argument from argument list.  More... | |
| #define | GET_ARGS_LESS_N(N, ...) Z_GET_ARGS_LESS_##N(__VA_ARGS__) | 
| Strips n first arguments from the argument list.  More... | |
| #define | UTIL_OR(a, b) COND_CODE_1(UTIL_BOOL(a), (a), (b)) | 
Like a || b, but does evaluation and short-circuiting at C preprocessor time.  More... | |
| #define | UTIL_AND(a, b) COND_CODE_1(UTIL_BOOL(a), (b), (0)) | 
Like a && b, but does evaluation and short-circuiting at C preprocessor time.  More... | |
| #define | UTIL_INC(x) UTIL_PRIMITIVE_CAT(UTIL_INC_, x) | 
| UTIL_INC(x) for an integer literal x from 0 to 255 expands to an integer literal whose value is x+1.  More... | |
| #define | UTIL_DEC(x) UTIL_PRIMITIVE_CAT(UTIL_DEC_, x) | 
| #define | UTIL_X2(y) UTIL_PRIMITIVE_CAT(UTIL_X2_, y) | 
| UTIL_X2(y) for an integer literal y from 0 to 255 expands to an integer literal whose value is 2y.  More... | |
| #define | LISTIFY(LEN, F, sep, ...) UTIL_CAT(Z_UTIL_LISTIFY_, LEN)(F, sep, __VA_ARGS__) | 
| Generates a sequence of code with configurable separator.  More... | |
| #define | FOR_EACH(F, sep, ...) Z_FOR_EACH(F, sep, REVERSE_ARGS(__VA_ARGS__)) | 
Call a macro F on each provided argument with a given separator between each call.  More... | |
| #define | FOR_EACH_NONEMPTY_TERM(F, term, ...) | 
| Like FOR_EACH(), but with a terminator instead of a separator, and drops empty elements from the argument list.  More... | |
| #define | FOR_EACH_IDX(F, sep, ...) Z_FOR_EACH_IDX(F, sep, REVERSE_ARGS(__VA_ARGS__)) | 
Call macro F on each provided argument, with the argument's index as an additional parameter.  More... | |
| #define | FOR_EACH_FIXED_ARG(F, sep, fixed_arg, ...) Z_FOR_EACH_FIXED_ARG(F, sep, fixed_arg, REVERSE_ARGS(__VA_ARGS__)) | 
Call macro F on each provided argument, with an additional fixed argument as a parameter.  More... | |
| #define | FOR_EACH_IDX_FIXED_ARG(F, sep, fixed_arg, ...) Z_FOR_EACH_IDX_FIXED_ARG(F, sep, fixed_arg, REVERSE_ARGS(__VA_ARGS__)) | 
Calls macro F for each variable argument with an index and fixed argument.  More... | |
| #define | REVERSE_ARGS(...) Z_FOR_EACH_ENGINE(Z_FOR_EACH_EXEC, (,), Z_BYPASS, _, __VA_ARGS__) | 
| Reverse arguments order.  More... | |
| #define | NUM_VA_ARGS_LESS_1(...) | 
| Number of arguments in the variable arguments list minus one.  More... | |
| #define | MACRO_MAP_CAT(...) MACRO_MAP_CAT_(__VA_ARGS__) | 
| Mapping macro that pastes results together.  More... | |
| #define | MACRO_MAP_CAT_N(N, ...) MACRO_MAP_CAT_N_(N, __VA_ARGS__) | 
| Mapping macro that pastes a fixed number of results together.  More... | |
Functions | |
| static bool | is_power_of_two (unsigned int x) | 
Is x a power of two?  More... | |
| static int64_t | arithmetic_shift_right (int64_t value, uint8_t shift) | 
| Arithmetic shift right.  More... | |
| static void | bytecpy (void *dst, const void *src, size_t size) | 
| byte by byte memcpy.  More... | |
| static void | byteswp (void *a, void *b, size_t size) | 
| byte by byte swap.  More... | |
| int | char2hex (char c, uint8_t *x) | 
| Convert a single character into a hexadecimal nibble.  More... | |
| int | hex2char (uint8_t x, char *c) | 
| Convert a single hexadecimal nibble into a character.  More... | |
| size_t | bin2hex (const uint8_t *buf, size_t buflen, char *hex, size_t hexlen) | 
| Convert a binary array into string representation.  More... | |
| size_t | hex2bin (const char *hex, size_t hexlen, uint8_t *buf, size_t buflen) | 
| Convert a hexadecimal string into a binary array.  More... | |
| static uint8_t | bcd2bin (uint8_t bcd) | 
| Convert a binary coded decimal (BCD 8421) value to binary.  More... | |
| static uint8_t | bin2bcd (uint8_t bin) | 
| Convert a binary value to binary coded decimal (BCD 8421).  More... | |
| uint8_t | u8_to_dec (char *buf, uint8_t buflen, uint8_t value) | 
| Convert a uint8_t into a decimal string representation.  More... | |
| char * | utf8_trunc (char *utf8_str) | 
| Properly truncate a NULL-terminated UTF-8 string.  More... | |
| char * | utf8_lcpy (char *dst, const char *src, size_t n) | 
Copies a UTF-8 encoded string from src to dst.  More... | |
| #define ARRAY_INDEX | ( | array, | |
| ptr | |||
| ) | 
#include <include/zephyr/sys/util.h>
Index of ptr within array. 
With CONFIG_ASSERT=y, this macro will trigger a runtime assertion when ptr does not fall into the range of array or when ptr is not aligned to an array-element boundary of array.
In C, passing a pointer as array causes a compile error.
| array | the array in question | 
| ptr | pointer to an element of array  | 
ptr within array, on success | #define ARRAY_INDEX_FLOOR | ( | array, | |
| ptr | |||
| ) | 
#include <include/zephyr/sys/util.h>
Array-index of ptr within array, rounded down. 
This macro behaves much like ARRAY_INDEX with the notable difference that it accepts any ptr in the range of array rather than exclusively a ptr aligned to an array-element boundary of array.
With CONFIG_ASSERT=y, this macro will trigger a runtime assertion when ptr does not fall into the range of array.
In C, passing a pointer as array causes a compile error.
| array | the array in question | 
| ptr | pointer to an element of array  | 
ptr within array, on success #include <include/zephyr/sys/util.h>
Number of elements in the given array. 
In C++, due to language limitations, this will accept as array any type that implements operator[]. The results may not be particularly meaningful in this case.
In C, passing a pointer as array causes a compile error. 
| #define BIT | ( | n | ) | (1UL << (n)) | 
#include <include/zephyr/sys/util_macro.h>
Unsigned integer with bit position n set (signed in assembly language). 
| #define BIT64 | ( | _n | ) | (1ULL << (_n)) | 
#include <include/zephyr/sys/util_macro.h>
64-bit unsigned integer with bit position _n set. 
| #define BIT64_MASK | ( | n | ) | (BIT64(n) - 1ULL) | 
#include <include/zephyr/sys/util_macro.h>
64-bit bit mask with bits 0 through n-1 (inclusive) set, or 0 if n is 0. 
| #define BIT_MASK | ( | n | ) | (BIT(n) - 1UL) | 
#include <include/zephyr/sys/util_macro.h>
Bit mask with bits 0 through n-1 (inclusive) set, or 0 if n is 0. 
| #define BITS_PER_LONG (__CHAR_BIT__ * __SIZEOF_LONG__) | 
#include <include/zephyr/sys/util.h>
Number of bits in a long int.
| #define BITS_PER_LONG_LONG (__CHAR_BIT__ * __SIZEOF_LONG_LONG__) | 
#include <include/zephyr/sys/util.h>
Number of bits in a long long int.
| #define ceiling_fraction | ( | numerator, | |
| divider | |||
| ) | 
#include <include/zephyr/sys/util.h>
Ceiling function applied to numerator / divider as a fraction. 
| #define CLAMP | ( | val, | |
| low, | |||
| high | |||
| ) | (((val) <= (low)) ? (low) : MIN(val, high)) | 
#include <include/zephyr/sys/util.h>
Clamp a value to a given range.
| val | Value to be clamped. | 
| low | Lowest allowed value (inclusive). | 
| high | Highest allowed value (inclusive). | 
| #define COND_CODE_0 | ( | _flag, | |
| _if_0_code, | |||
| _else_code | |||
| ) | Z_COND_CODE_0(_flag, _if_0_code, _else_code) | 
#include <include/zephyr/sys/util_macro.h>
Like COND_CODE_1() except tests if _flag is 0. 
This is like COND_CODE_1(), except that it tests whether _flag expands to the integer literal 0. It expands to _if_0_code if so, and _else_code otherwise; both of these must be enclosed in parentheses.
| _flag | evaluated flag | 
| _if_0_code | result if _flag expands to 0; must be in parentheses  | 
| _else_code | result otherwise; must be in parentheses | 
| #define COND_CODE_1 | ( | _flag, | |
| _if_1_code, | |||
| _else_code | |||
| ) | Z_COND_CODE_1(_flag, _if_1_code, _else_code) | 
#include <include/zephyr/sys/util_macro.h>
Insert code depending on whether _flag expands to 1 or not. 
This relies on similar tricks as IS_ENABLED(), but as the result of _flag expansion, results in either _if_1_code or _else_code is expanded.
To prevent the preprocessor from treating commas as argument separators, the _if_1_code and _else_code expressions must be inside brackets/parentheses: (). These are stripped away during macro expansion.
Example:
COND_CODE_1(CONFIG_FLAG, (uint32_t x;), (there_is_no_flag();))
 If CONFIG_FLAG is defined to 1, this expands to: 
uint32_t x;
 It expands to there_is_no_flag(); otherwise.
This could be used as an alternative to:
#if defined(CONFIG_FLAG) && (CONFIG_FLAG == 1) #define MAYBE_DECLARE(x) uint32_t x #else #define MAYBE_DECLARE(x) there_is_no_flag() #endif MAYBE_DECLARE(x);
 However, the advantage of COND_CODE_1() is that code is resolved in place where it is used, while the #if method defines MAYBE_DECLARE on two lines and requires it to be invoked again on a separate line. This makes COND_CODE_1() more concise and also sometimes more useful when used within another macro's expansion.
_flag can be the result of preprocessor expansion, e.g. an expression involving NUM_VA_ARGS_LESS_1(...). However, _if_1_code is only expanded if _flag expands to the integer literal 1. Integer expressions that evaluate to 1, e.g. after doing some arithmetic, will not work.| _flag | evaluated flag | 
| _if_1_code | result if _flag expands to 1; must be in parentheses  | 
| _else_code | result otherwise; must be in parentheses | 
#include <include/zephyr/sys/util.h>
Get a pointer to a structure containing the element.
Example:
 struct foo {
    int bar;
 };
 struct foo my_foo;
 int *ptr = &my_foo.bar;
 struct foo *container = CONTAINER_OF(ptr, struct foo, bar);
 Above, container points at my_foo.
| ptr | pointer to a structure element | 
| type | name of the type that ptr is an element of  | 
| field | the name of the field within the struct ptr points to  | 
ptr #include <include/zephyr/sys/util.h>
Divide and round up.
Example:
| n | Numerator. | 
| d | Denominator. | 
n / d, rounded up. | #define EMPTY | 
#include <include/zephyr/sys/util_macro.h>
Macro with an empty expansion.
This trivial definition is provided for readability when a macro should expand to an empty result, which e.g. is sometimes needed to silence checkpatch.
Example:
#define LIST_ITEM(n) , item##n
The above would cause checkpatch to complain, but:
#define LIST_ITEM(n) EMPTY, item##n
would not.
| #define FIELD_GET | ( | mask, | |
| value | |||
| ) | (((value) & (mask)) / LSB_GET(mask)) | 
#include <include/zephyr/sys/util.h>
Extract a bitfield element from value corresponding to the field mask mask. 
| #define FIELD_PREP | ( | mask, | |
| value | |||
| ) | (((value) * LSB_GET(mask)) & (mask)) | 
#include <include/zephyr/sys/util.h>
Prepare a bitfield element using value with mask representing its field position and width. The result should be combined with other fields using a logical OR. 
| #define FOR_EACH | ( | F, | |
| sep, | |||
| ... | |||
| ) | Z_FOR_EACH(F, sep, REVERSE_ARGS(__VA_ARGS__)) | 
#include <include/zephyr/sys/util_macro.h>
Call a macro F on each provided argument with a given separator between each call. 
Example:
#define F(x) int a##x FOR_EACH(F, (;), 4, 5, 6);
This expands to:
int a4; int a5; int a6;
| F | Macro to invoke | 
| sep | Separator (e.g. comma or semicolon). Must be in parentheses; this is required to enable providing a comma as separator. | 
| ... | Variable argument list. The macro F is invoked as F(element) for each element in the list.  | 
| #define FOR_EACH_FIXED_ARG | ( | F, | |
| sep, | |||
| fixed_arg, | |||
| ... | |||
| ) | Z_FOR_EACH_FIXED_ARG(F, sep, fixed_arg, REVERSE_ARGS(__VA_ARGS__)) | 
#include <include/zephyr/sys/util_macro.h>
Call macro F on each provided argument, with an additional fixed argument as a parameter. 
This is like FOR_EACH(), except F should be a macro which takes two arguments: F(variable_arg, fixed_arg).
Example:
static void func(int val, void *dev); FOR_EACH_FIXED_ARG(func, (;), dev, 4, 5, 6);
This expands to:
func(4, dev); func(5, dev); func(6, dev);
| F | Macro to invoke | 
| sep | Separator (e.g. comma or semicolon). Must be in parentheses; this is required to enable providing a comma as separator. | 
| fixed_arg | Fixed argument passed to F as the second macro parameter.  | 
| ... | Variable argument list. The macro F is invoked as F(element, fixed_arg) for each element in the list.  | 
| #define FOR_EACH_IDX | ( | F, | |
| sep, | |||
| ... | |||
| ) | Z_FOR_EACH_IDX(F, sep, REVERSE_ARGS(__VA_ARGS__)) | 
#include <include/zephyr/sys/util_macro.h>
Call macro F on each provided argument, with the argument's index as an additional parameter. 
This is like FOR_EACH(), except F should be a macro which takes two arguments: F(index, variable_arg).
Example:
#define F(idx, x) int a##idx = x FOR_EACH_IDX(F, (;), 4, 5, 6);
This expands to:
int a0 = 4; int a1 = 5; int a2 = 6;
| F | Macro to invoke | 
| sep | Separator (e.g. comma or semicolon). Must be in parentheses; this is required to enable providing a comma as separator. | 
| ... | Variable argument list. The macro F is invoked as F(index, element) for each element in the list.  | 
| #define FOR_EACH_IDX_FIXED_ARG | ( | F, | |
| sep, | |||
| fixed_arg, | |||
| ... | |||
| ) | Z_FOR_EACH_IDX_FIXED_ARG(F, sep, fixed_arg, REVERSE_ARGS(__VA_ARGS__)) | 
#include <include/zephyr/sys/util_macro.h>
Calls macro F for each variable argument with an index and fixed argument. 
This is like the combination of FOR_EACH_IDX() with FOR_EACH_FIXED_ARG().
Example:
#define F(idx, x, fixed_arg) int fixed_arg##idx = x FOR_EACH_IDX_FIXED_ARG(F, (;), a, 4, 5, 6);
This expands to:
int a0 = 4; int a1 = 5; int a2 = 6;
| F | Macro to invoke | 
| sep | Separator (e.g. comma or semicolon). Must be in parentheses; This is required to enable providing a comma as separator. | 
| fixed_arg | Fixed argument passed to F as the third macro parameter.  | 
| ... | Variable list of arguments. The macro F is invoked as F(index, element, fixed_arg) for each element in the list.  | 
| #define FOR_EACH_NONEMPTY_TERM | ( | F, | |
| term, | |||
| ... | |||
| ) | 
#include <include/zephyr/sys/util_macro.h>
Like FOR_EACH(), but with a terminator instead of a separator, and drops empty elements from the argument list.
The sep argument to FOR_EACH(F, (sep), a, b) is a separator which is placed between calls to F, like this: 
FOR_EACH(F, (sep), a, b) // F(a) sep F(b)
                         //               ^^^ no sep here!
 By contrast, the term argument to FOR_EACH_NONEMPTY_TERM(F, (term), a, b) is added after each time F appears in the expansion: 
FOR_EACH_NONEMPTY_TERM(F, (term), a, b) // F(a) term F(b) term
                                        //                ^^^^
Further, any empty elements are dropped:
FOR_EACH_NONEMPTY_TERM(F, (term), a, EMPTY, b) // F(a) term F(b) term
 This is more convenient in some cases, because FOR_EACH_NONEMPTY_TERM() expands to nothing when given an empty argument list, and it's often cumbersome to write a macro F that does the right thing even when given an empty argument.
One example is when __VA_ARGS__ may or may not be empty, and the results are embedded in a larger initializer: 
#define SQUARE(x) ((x)*(x))
int my_array[] = {
        FOR_EACH_NONEMPTY_TERM(SQUARE, (,), FOO(...))
        FOR_EACH_NONEMPTY_TERM(SQUARE, (,), BAR(...))
        FOR_EACH_NONEMPTY_TERM(SQUARE, (,), BAZ(...))
};
This is more convenient than:
FOO, BAR, and BAZ expansions are empty and adding a comma manually (or not) between FOR_EACH() callsFOO expands to nothing)| F | Macro to invoke on each nonempty element of the variable arguments | 
| term | Terminator (e.g. comma or semicolon) placed after each invocation of F. Must be in parentheses; this is required to enable providing a comma as separator. | 
| ... | Variable argument list. The macro F is invoked as F(element) for each nonempty element in the list.  | 
| #define GB | ( | x | ) | (MB(x) << 10) | 
#include <include/zephyr/sys/util.h>
Number of bytes in x gibibytes. 
| #define GENMASK | ( | h, | |
| l | |||
| ) | (((~0UL) - (1UL << (l)) + 1) & (~0UL >> (BITS_PER_LONG - 1 - (h)))) | 
#include <include/zephyr/sys/util.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)))) | 
#include <include/zephyr/sys/util.h>
Create a contiguous 64-bit bitmask starting at bit position l and ending at position h. 
| #define GET_ARG_N | ( | N, | |
| ... | |||
| ) | Z_GET_ARG_##N(__VA_ARGS__) | 
#include <include/zephyr/sys/util_macro.h>
Get nth argument from argument list.
| N | Argument index to fetch. Counter from 1. | 
| ... | Variable list of arguments from which one argument is returned. | 
| #define GET_ARGS_LESS_N | ( | N, | |
| ... | |||
| ) | Z_GET_ARGS_LESS_##N(__VA_ARGS__) | 
#include <include/zephyr/sys/util_macro.h>
Strips n first arguments from the argument list.
| N | Number of arguments to discard. | 
| ... | Variable list of arguments. | 
| #define IDENTITY | ( | V | ) | V | 
#include <include/zephyr/sys/util_macro.h>
Macro that expands to its argument.
This is useful in macros like FOR_EACH() when there is no transformation required on the list elements.
| V | any value | 
| #define IF_ENABLED | ( | _flag, | |
| _code | |||
| ) | COND_CODE_1(_flag, _code, ()) | 
#include <include/zephyr/sys/util_macro.h>
Insert code if _flag is defined and equals 1. 
Like COND_CODE_1(), this expands to _code if _flag is defined to 1; it expands to nothing otherwise.
Example:
IF_ENABLED(CONFIG_FLAG, (uint32_t foo;))
 If CONFIG_FLAG is defined to 1, this expands to: 
uint32_t foo;
and to nothing otherwise.
It can be considered as a more compact alternative to:
#if defined(CONFIG_FLAG) && (CONFIG_FLAG == 1) uint32_t foo; #endif
| _flag | evaluated flag | 
| _code | result if _flag expands to 1; must be in parentheses  | 
| #define IN_RANGE | ( | val, | |
| min, | |||
| max | |||
| ) | ((val) >= (min) && (val) <= (max)) | 
#include <include/zephyr/sys/util.h>
Checks if a value is within range.
val is evaluated twice.| val | Value to be checked. | 
| min | Lower bound (inclusive). | 
| max | Upper bound (inclusive). | 
| true | If value is within range | 
| false | If the value is not within range | 
| #define INT_TO_POINTER | ( | x | ) | ((void *) (intptr_t) (x)) | 
#include <include/zephyr/sys/util.h>
Cast x, a signed integer, to a void*. 
| #define IS_ARRAY | ( | array | ) | 
#include <include/zephyr/sys/util.h>
Zero if array has an array type, a compile error otherwise. 
This macro is available only from C, not C++.
| #define IS_ARRAY_ELEMENT | ( | array, | |
| ptr | |||
| ) | 
#include <include/zephyr/sys/util.h>
Whether ptr is an element of array. 
This macro can be seen as a slightly stricter version of PART_OF_ARRAY in that it also ensures that ptr is aligned to an array-element boundary of array.
In C, passing a pointer as array causes a compile error.
| array | the array in question | 
| ptr | the pointer to check | 
ptr is part of array, 0 otherwise | #define IS_BIT_MASK | ( | m | ) | IS_SHIFTED_BIT_MASK(m, 0) | 
#include <include/zephyr/sys/util_macro.h>
Check if bits are set continuously from the LSB.
| m | Check whether the bits are set continuously from LSB. | 
| #define IS_EMPTY | ( | ... | ) | Z_IS_EMPTY_(__VA_ARGS__) | 
#include <include/zephyr/sys/util_macro.h>
Check if a macro has a replacement expression.
If a is a macro defined to a nonempty value, this will return true, otherwise it will return false. It only works with defined macros, so an additional #ifdef test may be needed in some cases.
This macro may be used with COND_CODE_1() and COND_CODE_0() while processing __VA_ARGS__ to avoid processing empty arguments.
Example:
#define EMPTY #define NON_EMPTY 1 #undef UNDEFINED IS_EMPTY(EMPTY) IS_EMPTY(NON_EMPTY) IS_EMPTY(UNDEFINED) #if defined(EMPTY) && IS_EMPTY(EMPTY) == true some_conditional_code #endif
 In above examples, the invocations of IS_EMPTY(...) return true, false, and true; some_conditional_code is included.
| ... | macro to check for emptiness (may be __VA_ARGS__)  | 
| #define IS_ENABLED | ( | config_macro | ) | Z_IS_ENABLED1(config_macro) | 
#include <include/zephyr/sys/util_macro.h>
Check for macro definition in compiler-visible expressions.
This trick was pioneered in Linux as the config_enabled() macro. It has the effect of taking a macro value that may be defined to "1" or may not be defined at all and turning it into a literal expression that can be handled by the C compiler instead of just the preprocessor. It is often used with a CONFIG_FOO macro which may be defined to 1 via Kconfig, or left undefined.
That is, it works similarly to #if defined(CONFIG_FOO) except that its expansion is a C expression. Thus, much #ifdef usage can be replaced with equivalents like: 
if (IS_ENABLED(CONFIG_FOO)) {
        do_something_with_foo
}
 This is cleaner since the compiler can generate errors and warnings for do_something_with_foo even when CONFIG_FOO is undefined.
Note: Use of IS_ENABLED in a #if statement is discouraged as it doesn't provide any benefit vs plain #if defined()
| config_macro | Macro to check | 
config_macro is defined to 1, 0 otherwise (including if config_macro is not defined) | #define IS_EQ | ( | a, | |
| b | |||
| ) | Z_IS_EQ(a, b) | 
#include <include/zephyr/sys/util_macro.h>
Like a == b, but does evaluation and short-circuiting at C preprocessor time. 
This however only works for integer literal from 0 to 255.
| #define IS_POWER_OF_TWO | ( | x | ) | (((x) != 0U) && (((x) & ((x) - 1U)) == 0U)) | 
#include <include/zephyr/sys/util_macro.h>
Check if a x is a power of two. 
#include <include/zephyr/sys/util_macro.h>
Check if bits are set continuously from the specified bit.
The macro is not dependent on the bit-width.
| m | Check whether the bits are set continuously or not. | 
| s | Specify the lowest bit for that is continuously set bits. | 
| #define KB | ( | x | ) | ((x) << 10) | 
#include <include/zephyr/sys/util.h>
Number of bytes in x kibibytes. 
| #define KHZ | ( | x | ) | ((x) * 1000) | 
#include <include/zephyr/sys/util.h>
Number of Hz in x kHz. 
| #define LIST_DROP_EMPTY | ( | ... | ) | Z_LIST_DROP_FIRST(FOR_EACH(Z_LIST_NO_EMPTIES, (), __VA_ARGS__)) | 
#include <include/zephyr/sys/util_macro.h>
Remove empty arguments from list.
During macro expansion, __VA_ARGS__ and other preprocessor generated lists may contain empty elements, e.g.: 
#define LIST ,a,b,,d,
Using EMPTY to show each empty element, LIST contains:
EMPTY, a, b, EMPTY, d
When processing such lists, e.g. using FOR_EACH(), all empty elements will be processed, and may require filtering out. To make that process easier, it is enough to invoke LIST_DROP_EMPTY which will remove all empty elements.
Example:
LIST_DROP_EMPTY(LIST)
expands to:
a, b, d
| ... | list to be processed | 
| #define LISTIFY | ( | LEN, | |
| F, | |||
| sep, | |||
| ... | |||
| ) | UTIL_CAT(Z_UTIL_LISTIFY_, LEN)(F, sep, __VA_ARGS__) | 
#include <include/zephyr/sys/util_macro.h>
Generates a sequence of code with configurable separator.
Example:
#define FOO(i, _) MY_PWM ## i
{ LISTIFY(PWM_COUNT, FOO, (,)) }
The above two lines expand to:
{ MY_PWM0 , MY_PWM1 }
| LEN | The length of the sequence. Must be an integer literal less than 255. | 
| F | A macro function that accepts at least two arguments: F(i, ...). F is called repeatedly in the expansion. Its first argument i is the index in the sequence, and the variable list of arguments passed to LISTIFY are passed through to F. | 
| sep | Separator (e.g. comma or semicolon). Must be in parentheses; this is required to enable providing a comma as separator. | 
| #define LOG2 | ( | x | ) | ((x) < 1 ? -1 : __z_log2(x)) | 
#include <include/zephyr/sys/util.h>
Compute log2(x)
| x | An unsigned integral value to compute logarithm of (positive only) | 
| #define LOG2CEIL | ( | x | ) | ((x) < 1 ? 0 : __z_log2((x)-1) + 1) | 
#include <include/zephyr/sys/util.h>
Compute ceil(log2(x))
| x | An unsigned integral value | 
| #define LSB_GET | ( | value | ) | ((value) & -(value)) | 
#include <include/zephyr/sys/util.h>
Extract the Least Significant Bit from value. 
| #define MACRO_MAP_CAT | ( | ... | ) | MACRO_MAP_CAT_(__VA_ARGS__) | 
#include <include/zephyr/sys/util_macro.h>
Mapping macro that pastes results together.
This is similar to FOR_EACH() in that it invokes a macro repeatedly on each element of __VA_ARGS__. However, unlike FOR_EACH(), MACRO_MAP_CAT() pastes the results together into a single token.
For example, with this macro FOO:
#define FOO(x) item_##x##_
 MACRO_MAP_CAT(FOO, a, b, c), expands to the token: 
item_a_item_b_item_c_
| ... | Macro to expand on each argument, followed by its arguments. (The macro should take exactly one argument.) | 
| #define MACRO_MAP_CAT_N | ( | N, | |
| ... | |||
| ) | MACRO_MAP_CAT_N_(N, __VA_ARGS__) | 
#include <include/zephyr/sys/util_macro.h>
Mapping macro that pastes a fixed number of results together.
Similar to MACRO_MAP_CAT(), but expects a fixed number of arguments. If more arguments are given than are expected, the rest are ignored.
| N | Number of arguments to map | 
| ... | Macro to expand on each argument, followed by its arguments. (The macro should take exactly one argument.) | 
| #define MAX | ( | a, | |
| b | |||
| ) | (((a) > (b)) ? (a) : (b)) | 
#include <include/zephyr/sys/util.h>
Obtain the maximum of two values.
| a | First value. | 
| b | Second value. | 
a and b. | #define MB | ( | x | ) | (KB(x) << 10) | 
#include <include/zephyr/sys/util.h>
Number of bytes in x mebibytes. 
| #define MHZ | ( | x | ) | (KHZ(x) * 1000) | 
#include <include/zephyr/sys/util.h>
Number of Hz in x MHz. 
| #define MIN | ( | a, | |
| b | |||
| ) | (((a) < (b)) ? (a) : (b)) | 
#include <include/zephyr/sys/util.h>
Obtain the minimum of two values.
| a | First value. | 
| b | Second value. | 
a and b. | #define NHPOT | ( | x | ) | ((x) < 1 ? 1 : ((x) > (1ULL<<63) ? 0 : 1ULL << LOG2CEIL(x))) | 
#include <include/zephyr/sys/util.h>
Compute next highest power of two.
Equivalent to 2^ceil(log2(x))
| x | An unsigned integral value | 
| #define NUM_VA_ARGS_LESS_1 | ( | ... | ) | 
#include <include/zephyr/sys/util_macro.h>
Number of arguments in the variable arguments list minus one.
| ... | List of arguments | 
| #define PART_OF_ARRAY | ( | array, | |
| ptr | |||
| ) | 
#include <include/zephyr/sys/util.h>
Check if a pointer ptr lies within array. 
In C but not C++, this causes a compile error if array is not an array (e.g. if ptr and array are mixed up).
| array | an array | 
| ptr | a pointer | 
ptr is part of array, 0 otherwise | #define POINTER_TO_INT | ( | x | ) | ((intptr_t) (x)) | 
#include <include/zephyr/sys/util.h>
Cast x, a pointer, to a signed integer. 
| #define POINTER_TO_UINT | ( | x | ) | ((uintptr_t) (x)) | 
#include <include/zephyr/sys/util.h>
Cast x, a pointer, to an unsigned integer. 
| #define REVERSE_ARGS | ( | ... | ) | Z_FOR_EACH_ENGINE(Z_FOR_EACH_EXEC, (,), Z_BYPASS, _, __VA_ARGS__) | 
#include <include/zephyr/sys/util_macro.h>
Reverse arguments order.
| ... | Variable argument list. | 
#include <include/zephyr/sys/util.h>
Value of x rounded down to the previous multiple of align, which must be a power of 2. 
| #define ROUND_UP | ( | x, | |
| align | |||
| ) | 
#include <include/zephyr/sys/util.h>
Value of x rounded up to the next multiple of align, which must be a power of 2. 
| #define UINT_TO_POINTER | ( | x | ) | ((void *) (uintptr_t) (x)) | 
#include <include/zephyr/sys/util.h>
Cast x, an unsigned integer, to a void*. 
| #define UTIL_AND | ( | a, | |
| b | |||
| ) | COND_CODE_1(UTIL_BOOL(a), (b), (0)) | 
#include <include/zephyr/sys/util_macro.h>
Like a && b, but does evaluation and short-circuiting at C preprocessor time. 
This is not the same as the binary &&, however; in particular, a should expand to an integer literal 0 or 1. However, b can be any value.
This can be useful when b is an expression that would cause a build error when a is 0. 
| #define UTIL_DEC | ( | x | ) | UTIL_PRIMITIVE_CAT(UTIL_DEC_, x) | 
#include <include/zephyr/sys/util_macro.h>
| #define UTIL_INC | ( | x | ) | UTIL_PRIMITIVE_CAT(UTIL_INC_, x) | 
#include <include/zephyr/sys/util_macro.h>
UTIL_INC(x) for an integer literal x from 0 to 255 expands to an integer literal whose value is x+1.
Similarly, UTIL_DEC(x) is (x-1) as an integer literal.
| #define UTIL_OR | ( | a, | |
| b | |||
| ) | COND_CODE_1(UTIL_BOOL(a), (a), (b)) | 
#include <include/zephyr/sys/util_macro.h>
Like a || b, but does evaluation and short-circuiting at C preprocessor time. 
This is not the same as the binary || operator; in particular, a should expand to an integer literal 0 or 1. However, b can be any value.
This can be useful when b is an expression that would cause a build error when a is 1. 
| #define UTIL_X2 | ( | y | ) | UTIL_PRIMITIVE_CAT(UTIL_X2_, y) | 
#include <include/zephyr/sys/util_macro.h>
UTIL_X2(y) for an integer literal y from 0 to 255 expands to an integer literal whose value is 2y.
| #define WAIT_FOR | ( | expr, | |
| timeout, | |||
| delay_stmt | |||
| ) | 
#include <include/zephyr/sys/util.h>
Wait for an expression to return true with a timeout.
Spin on an expression with a timeout and optional delay between iterations
Commonly needed when waiting on hardware to complete an asynchronous request to read/write/initialize/reset, but useful for any expression.
| expr | Truth expression upon which to poll, e.g.: XYZREG & XYZREG_EN | 
| timeout | Timeout to wait for in microseconds, e.g.: 1000 (1ms) | 
| delay_stmt | Delay statement to perform each poll iteration e.g.: NULL, k_yield(), k_msleep(1) or k_busy_wait(1) | 
| expr | As a boolean return, if false then it has timed out. | 
| #define WB_DN | ( | x | ) | ROUND_DOWN(x, sizeof(void *)) | 
#include <include/zephyr/sys/util.h>
Value of x rounded down to the previous word boundary. 
#include <include/zephyr/sys/util.h>
Value of x rounded up to the next word boundary. 
#include <include/zephyr/sys/util_macro.h>
Set or clear a bit depending on a boolean value.
The argument var is a variable whose value is written to as a side effect.
| var | Variable to be altered | 
| bit | Bit number | 
| set | if 0, clears bit in var; any other value sets bit  | 
| #define ZERO_OR_COMPILE_ERROR | ( | cond | ) | ((int) sizeof(char[1 - 2 * !(cond)]) - 1) | 
#include <include/zephyr/sys/util.h>
0 if cond is true-ish; causes a compile error otherwise. 
#include <include/zephyr/sys/util.h>
Arithmetic shift right.
| value | value to shift | 
| shift | number of bits to shift | 
value shifted right by shift; opened bit positions are filled with the sign bit #include <include/zephyr/sys/util.h>
Convert a binary coded decimal (BCD 8421) value to binary.
| bcd | BCD 8421 value to convert. | 
#include <include/zephyr/sys/util.h>
Convert a binary value to binary coded decimal (BCD 8421).
| bin | Binary value to convert. | 
#include <include/zephyr/sys/util.h>
Convert a binary array into string representation.
| buf | The binary array to convert | 
| buflen | The length of the binary array to convert | 
| hex | Address of where to store the string representation. | 
| hexlen | Size of the storage area for string representation. | 
      
  | 
  inlinestatic | 
#include <include/zephyr/sys/util.h>
byte by byte memcpy.
Copy size bytes of src into dest. This is guaranteed to be done byte by byte.
| dst | Pointer to the destination memory. | 
| src | Pointer to the source of the data. | 
| size | The number of bytes to copy. | 
      
  | 
  inlinestatic | 
#include <include/zephyr/sys/util.h>
byte by byte swap.
Swap size bytes between memory regions a and b. This is guaranteed to be done byte by byte.
| a | Pointer to the the first memory region. | 
| b | Pointer to the the second memory region. | 
| size | The number of bytes to swap. | 
| int char2hex | ( | char | c, | 
| uint8_t * | x | ||
| ) | 
#include <include/zephyr/sys/util.h>
Convert a single character into a hexadecimal nibble.
| c | The character to convert | 
| x | The address of storage for the converted number. | 
#include <include/zephyr/sys/util.h>
Convert a hexadecimal string into a binary array.
| hex | The hexadecimal string to convert | 
| hexlen | The length of the hexadecimal string to convert. | 
| buf | Address of where to store the binary data | 
| buflen | Size of the storage area for binary data | 
| int hex2char | ( | uint8_t | x, | 
| char * | c | ||
| ) | 
#include <include/zephyr/sys/util.h>
Convert a single hexadecimal nibble into a character.
| c | The number to convert | 
| x | The address of storage for the converted character. | 
#include <include/zephyr/sys/util.h>
Is x a power of two? 
| x | value to check | 
x is a power of two, false otherwise #include <include/zephyr/sys/util.h>
Convert a uint8_t into a decimal string representation.
Convert a uint8_t value into its ASCII decimal string representation. The string is terminated if there is enough space in buf.
| buf | Address of where to store the string representation. | 
| buflen | Size of the storage area for string representation. | 
| value | The value to convert to decimal string | 
| char * utf8_lcpy | ( | char * | dst, | 
| const char * | src, | ||
| size_t | n | ||
| ) | 
#include <include/zephyr/sys/util.h>
Copies a UTF-8 encoded string from src to dst. 
The resulting dst will always be NULL terminated if n is larger than 0, and the dst string will always be properly UTF-8 truncated.
| dst | The destination of the UTF-8 string. | 
| src | The source string | 
| n | The size of the dst buffer. Maximum number of characters copied is n - 1. If 0 nothing will be done, and the dst will not be NULL terminated. | 
dst | char * utf8_trunc | ( | char * | utf8_str | ) | 
#include <include/zephyr/sys/util.h>
Properly truncate a NULL-terminated UTF-8 string.
Take a NULL-terminated UTF-8 string and ensure that if the string has been truncated (by setting the NULL terminator) earlier by other means, that the string ends with a properly formatted UTF-8 character (1-4 bytes).
Example: char test_str[] = "€€€"; char trunc_utf8[8]; printf("Original : %s\n", test_str); // €€€ strncpy(trunc_utf8, test_str, sizeof(trunc_utf8)); trunc_utf8[sizeof(trunc_utf8) - 1] = '\0'; printf("Bad : %s\n", trunc_utf8); // €€� utf8_trunc(trunc_utf8); printf("Truncated: %s\n", trunc_utf8); // €€
| utf8_str | NULL-terminated string | 
utf8_str