1/*
2 * Copyright (c) 2016-2017 Dmitry V. Levin <ldv@altlinux.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. The name of the author may not be used to endorse or promote products
14 *    derived from this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#ifdef HAVE_CONFIG_H
29# include "config.h"
30#endif
31
32#include <stdbool.h>
33#include <stdlib.h>
34#include <string.h>
35#include "number_set.h"
36#include "xmalloc.h"
37
38typedef unsigned int number_slot_t;
39#define BITS_PER_SLOT (sizeof(number_slot_t) * 8)
40
41struct number_set {
42	number_slot_t *vec;
43	unsigned int nslots;
44	bool not;
45};
46
47static void
48number_setbit(const unsigned int i, number_slot_t *const vec)
49{
50	vec[i / BITS_PER_SLOT] |= (number_slot_t) 1 << (i % BITS_PER_SLOT);
51}
52
53static bool
54number_isset(const unsigned int i, const number_slot_t *const vec)
55{
56	return vec[i / BITS_PER_SLOT] & ((number_slot_t) 1 << (i % BITS_PER_SLOT));
57}
58
59static void
60reallocate_number_set(struct number_set *const set, const unsigned int new_nslots)
61{
62	if (new_nslots <= set->nslots)
63		return;
64	set->vec = xreallocarray(set->vec, new_nslots, sizeof(*set->vec));
65	memset(set->vec + set->nslots, 0,
66	       sizeof(*set->vec) * (new_nslots - set->nslots));
67	set->nslots = new_nslots;
68}
69
70bool
71number_set_array_is_empty(const struct number_set *const set,
72			  const unsigned int idx)
73{
74	return !(set && (set[idx].nslots || set[idx].not));
75}
76
77bool
78is_number_in_set(const unsigned int number, const struct number_set *const set)
79{
80	return set && ((number / BITS_PER_SLOT < set->nslots)
81		&& number_isset(number, set->vec)) ^ set->not;
82}
83
84bool
85is_number_in_set_array(const unsigned int number, const struct number_set *const set,
86		       const unsigned int idx)
87{
88	return set && ((number / BITS_PER_SLOT < set[idx].nslots)
89		&& number_isset(number, set[idx].vec)) ^ set[idx].not;
90}
91
92void
93add_number_to_set(const unsigned int number, struct number_set *const set)
94{
95	reallocate_number_set(set, number / BITS_PER_SLOT + 1);
96	number_setbit(number, set->vec);
97}
98
99void
100add_number_to_set_array(const unsigned int number, struct number_set *const set,
101			const unsigned int idx)
102{
103	add_number_to_set(number, &set[idx]);
104}
105
106void
107clear_number_set_array(struct number_set *const set, const unsigned int nmemb)
108{
109	unsigned int i;
110
111	for (i = 0; i < nmemb; ++i) {
112		if (set[i].nslots)
113			memset(set[i].vec, 0,
114			       sizeof(*set[i].vec) * set[i].nslots);
115		set[i].not = false;
116	}
117}
118
119void
120invert_number_set_array(struct number_set *const set, const unsigned int nmemb)
121{
122	unsigned int i;
123
124	for (i = 0; i < nmemb; ++i)
125		set[i].not = !set[i].not;
126}
127
128struct number_set *
129alloc_number_set_array(const unsigned int nmemb)
130{
131	return xcalloc(nmemb, sizeof(struct number_set));
132}
133
134void
135free_number_set_array(struct number_set *const set, unsigned int nmemb)
136{
137	while (nmemb) {
138		--nmemb;
139		free(set[nmemb].vec);
140		set[nmemb].vec = NULL;
141	}
142	free(set);
143}
144