1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <kunit/test.h>
4 #include <linux/gcd.h>
5 #include <linux/limits.h>
6 
7 struct test_case_params {
8 	unsigned long val1;
9 	unsigned long val2;
10 	unsigned long expected_result;
11 	const char *name;
12 };
13 
14 static const struct test_case_params params[] = {
15 	{ 48, 18, 6, "GCD of 48 and 18" },
16 	{ 18, 48, 6, "GCD of 18 and 48" },
17 	{ 56, 98, 14, "GCD of 56 and 98" },
18 	{ 17, 13, 1, "Coprime numbers" },
19 	{ 101, 103, 1, "Coprime numbers" },
20 	{ 270, 192, 6, "GCD of 270 and 192" },
21 	{ 0, 5, 5, "GCD with zero" },
22 	{ 7, 0, 7, "GCD with zero reversed" },
23 	{ 36, 36, 36, "GCD of identical numbers" },
24 	{ ULONG_MAX, 1, 1, "GCD of max ulong and 1" },
25 	{ ULONG_MAX, ULONG_MAX, ULONG_MAX, "GCD of max ulong values" },
26 };
27 
28 static void get_desc(const struct test_case_params *tc, char *desc)
29 {
30 	strscpy(desc, tc->name, KUNIT_PARAM_DESC_SIZE);
31 }
32 
33 KUNIT_ARRAY_PARAM(gcd, params, get_desc);
34 
35 static void gcd_test(struct kunit *test)
36 {
37 	const struct test_case_params *tc = (const struct test_case_params *)test->param_value;
38 
39 	KUNIT_EXPECT_EQ(test, tc->expected_result, gcd(tc->val1, tc->val2));
40 }
41 
42 static struct kunit_case math_gcd_test_cases[] = {
43 	KUNIT_CASE_PARAM(gcd_test, gcd_gen_params),
44 	{}
45 };
46 
47 static struct kunit_suite gcd_test_suite = {
48 	.name = "math-gcd",
49 	.test_cases = math_gcd_test_cases,
50 };
51 
52 kunit_test_suite(gcd_test_suite);
53 
54 MODULE_LICENSE("GPL");
55 MODULE_DESCRIPTION("math.gcd KUnit test suite");
56 MODULE_AUTHOR("Yu-Chun Lin <eleanor15x@gmail.com>");
57