util.h

 1// Copyright 2022 Stefan Kerkmann (KarlK90)
 2// Copyright 2011 Jun Wako <wakojun@gmail.com>
 3// SPDX-License-Identifier: GPL-2.0-or-later
 4
 5#pragma once
 6
 7#include "bits.h"
 8#include "bitwise.h"
 9
10// convert to string
11#define STR(s) XSTR(s)
12#define XSTR(s) #s
13
14#if !defined(MIN)
15#    define MIN(x, y) (((x) < (y)) ? (x) : (y))
16#endif
17
18#if !defined(MAX)
19#    define MAX(x, y) (((x) > (y)) ? (x) : (y))
20#endif
21
22#if !defined(CEILING)
23/**
24 * @brief Computes the rounded up result of a division of two integers at
25 * compile time.
26 */
27#    define CEILING(dividend, divisor) (((dividend) + (divisor)-1) / (divisor))
28#endif
29
30#if !defined(IS_ARRAY)
31/**
32 * @brief Returns true if the value is an array, false if it's a pointer.
33 *
34 * This macro is ill-formed for scalars, which is OK for its intended use in
35 * ARRAY_SIZE.
36 */
37#    define IS_ARRAY(value) (!__builtin_types_compatible_p(typeof((value)), typeof(&(value)[0])))
38#endif
39
40#if !defined(ARRAY_SIZE)
41/**
42 * @brief Computes the number of elements of the given array at compile time.
43 *
44 * This Macro can only be used for statically allocated arrays that have not
45 * been decayed into a pointer. This is detected at compile time, though the
46 * error message for scalar values is poor.
47 */
48#    define ARRAY_SIZE(array) (__builtin_choose_expr(IS_ARRAY((array)), sizeof((array)) / sizeof((array)[0]), (void)0))
49#endif
50
51#if !defined(PACKED)
52#    define PACKED __attribute__((__packed__))
53#endif
54
55#if __has_include("_util.h")
56#    include "_util.h" /* Include the platform's _util.h */
57#endif