56 lines
1.6 KiB
C
56 lines
1.6 KiB
C
|
/* SPDX-License-Identifier: GPL-2.0 */
|
||
|
#ifndef _LINUX_HELPER_MACROS_H_
|
||
|
#define _LINUX_HELPER_MACROS_H_
|
||
|
|
||
|
#include <linux/math.h>
|
||
|
|
||
|
#define __find_closest(x, a, as, op) \
|
||
|
({ \
|
||
|
typeof(as) __fc_i, __fc_as = (as) - 1; \
|
||
|
typeof(x) __fc_x = (x); \
|
||
|
typeof(*a) const *__fc_a = (a); \
|
||
|
for (__fc_i = 0; __fc_i < __fc_as; __fc_i++) { \
|
||
|
if (__fc_x op DIV_ROUND_CLOSEST(__fc_a[__fc_i] + \
|
||
|
__fc_a[__fc_i + 1], 2)) \
|
||
|
break; \
|
||
|
} \
|
||
|
(__fc_i); \
|
||
|
})
|
||
|
|
||
|
/**
|
||
|
* find_closest - locate the closest element in a sorted array
|
||
|
* @x: The reference value.
|
||
|
* @a: The array in which to look for the closest element. Must be sorted
|
||
|
* in ascending order.
|
||
|
* @as: Size of 'a'.
|
||
|
*
|
||
|
* Returns the index of the element closest to 'x'.
|
||
|
*/
|
||
|
#define find_closest(x, a, as) __find_closest(x, a, as, <=)
|
||
|
|
||
|
/**
|
||
|
* find_closest_descending - locate the closest element in a sorted array
|
||
|
* @x: The reference value.
|
||
|
* @a: The array in which to look for the closest element. Must be sorted
|
||
|
* in descending order.
|
||
|
* @as: Size of 'a'.
|
||
|
*
|
||
|
* Similar to find_closest() but 'a' is expected to be sorted in descending
|
||
|
* order.
|
||
|
*/
|
||
|
#define find_closest_descending(x, a, as) __find_closest(x, a, as, >=)
|
||
|
|
||
|
/**
|
||
|
* is_insidevar - check if the @ptr points inside the @var memory range.
|
||
|
* @ptr: the pointer to a memory address.
|
||
|
* @var: the variable which address and size identify the memory range.
|
||
|
*
|
||
|
* Evaluates to true if the address in @ptr lies within the memory
|
||
|
* range allocated to @var.
|
||
|
*/
|
||
|
#define is_insidevar(ptr, var) \
|
||
|
((uintptr_t)(ptr) >= (uintptr_t)(var) && \
|
||
|
(uintptr_t)(ptr) < (uintptr_t)(var) + sizeof(var))
|
||
|
|
||
|
#endif
|