xref: /freebsd/lib/libc/tests/string/fls_test.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 /*-
2  * Copyright (c) 2023 The FreeBSD Foundation
3  *
4  * This software was developed by Robert Clausecker <fuz@FreeBSD.org>
5  * under sponsorship from the FreeBSD Foundation.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ''AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE
27  */
28 
29 #include <atf-c.h>
30 #include <limits.h>
31 #include <stdint.h>
32 #include <strings.h>
33 
34 #ifndef FLS
35 # define FLS fls
36 # define TYPE int
37 # define TYPE_MIN INT_MIN
38 #endif
39 
40 ATF_TC_WITHOUT_HEAD(zero);
41 ATF_TC_BODY(zero, tc)
42 {
43 	ATF_CHECK_EQ((TYPE)0, FLS(0));
44 }
45 
46 ATF_TC_WITHOUT_HEAD(twobit);
47 ATF_TC_BODY(twobit, tc)
48 {
49 	const TYPE one = 1;
50 	TYPE x;
51 	const int n = sizeof(TYPE) * CHAR_BIT;
52 	int i, j;
53 
54 	for (i = 0; i < n - 1; i++)
55 		for (j = 0; j <= i; j++) {
56 			x = one << i | one << j;
57 			ATF_CHECK_EQ_MSG(i + 1, FLS(x),
58 			    "%s(%#jx) == %d != %d", __STRING(FLS), (intmax_t)x, FLS(x), i + 1);
59 		}
60 }
61 
62 ATF_TC_WITHOUT_HEAD(twobitneg);
63 ATF_TC_BODY(twobitneg, tc)
64 {
65 	const TYPE one = 1;
66 	TYPE x;
67 	const int n = sizeof(TYPE) * CHAR_BIT;
68 	int i, j;
69 
70 	for (i = 0; i < n - 1; i++)
71 		for (j = 0; j <= i; j++) {
72 			x = one << i | one << j | TYPE_MIN;
73 			ATF_CHECK_EQ_MSG(n, FLS(x),
74 			    "%s(%#jx) == %d != %d", __STRING(FLS), (intmax_t)x, FLS(x), n);
75 		}
76 }
77 
78 
79 ATF_TP_ADD_TCS(tp)
80 {
81 
82 	ATF_TP_ADD_TC(tp, zero);
83 	ATF_TP_ADD_TC(tp, twobit);
84 	ATF_TP_ADD_TC(tp, twobitneg);
85 
86 	return (atf_no_error());
87 }
88