xref: /third_party/libinput/src/util-bits.h (revision a46c0ec8) 
1/*
2 * Copyright © 2008-2011 Kristian Høgsberg
3 * Copyright © 2011 Intel Corporation
4 * Copyright © 2013-2015 Red Hat, Inc.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice (including the next
14 * paragraph) shall be included in all copies or substantial portions of the
15 * Software.
16 *
17 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
20 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
22 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
23 * DEALINGS IN THE SOFTWARE.
24 */
25
26#pragma once
27
28#include "config.h"
29
30#include <assert.h>
31#include <stdbool.h>
32#include <stddef.h>
33
34#define bit(x_) (1UL << (x_))
35#define NBITS(b) (b * 8)
36#define LONG_BITS (sizeof(long) * 8)
37#define NLONGS(x) (((x) + LONG_BITS - 1) / LONG_BITS)
38#define NCHARS(x) ((size_t)(((x) + 7) / 8))
39
40/* This bitfield helper implementation is taken from from libevdev-util.h,
41 * except that it has been modified to work with arrays of unsigned chars
42 */
43
44static inline bool
45bit_is_set(const unsigned char *array, int bit)
46{
47	return !!(array[bit / 8] & (1 << (bit % 8)));
48}
49
50static inline void
51set_bit(unsigned char *array, int bit)
52{
53	array[bit / 8] |= (1 << (bit % 8));
54}
55
56	static inline void
57clear_bit(unsigned char *array, int bit)
58{
59	array[bit / 8] &= ~(1 << (bit % 8));
60}
61
62static inline bool
63long_bit_is_set(const unsigned long *array, int bit)
64{
65	return !!(array[bit / LONG_BITS] & (1ULL << (bit % LONG_BITS)));
66}
67
68static inline void
69long_set_bit(unsigned long *array, int bit)
70{
71	array[bit / LONG_BITS] |= (1ULL << (bit % LONG_BITS));
72}
73
74static inline void
75long_clear_bit(unsigned long *array, int bit)
76{
77	array[bit / LONG_BITS] &= ~(1ULL << (bit % LONG_BITS));
78}
79
80static inline void
81long_set_bit_state(unsigned long *array, int bit, int state)
82{
83	if (state)
84		long_set_bit(array, bit);
85	else
86		long_clear_bit(array, bit);
87}
88
89static inline bool
90long_any_bit_set(unsigned long *array, size_t size)
91{
92	unsigned long i;
93
94	assert(size > 0);
95
96	for (i = 0; i < size; i++)
97		if (array[i] != 0)
98			return true;
99	return false;
100}
101