1// SPDX-License-Identifier: LGPL-2.1+
 2
 3#include <kunit/test.h>
 4#include <linux/time.h>
 5
 6/*
 7 * Traditional implementation of leap year evaluation.
 8 */
 9static bool is_leap(long year)
10{
11	return year % 4 == 0 && (year % 100 != 0 || year % 400 == 0);
12}
13
14/*
15 * Gets the last day of a month.
16 */
17static int last_day_of_month(long year, int month)
18{
19	if (month == 2)
20		return 28 + is_leap(year);
21	if (month == 4 || month == 6 || month == 9 || month == 11)
22		return 30;
23	return 31;
24}
25
26/*
27 * Advances a date by one day.
28 */
29static void advance_date(long *year, int *month, int *mday, int *yday)
30{
31	if (*mday != last_day_of_month(*year, *month)) {
32		++*mday;
33		++*yday;
34		return;
35	}
36
37	*mday = 1;
38	if (*month != 12) {
39		++*month;
40		++*yday;
41		return;
42	}
43
44	*month = 1;
45	*yday  = 0;
46	++*year;
47}
48
49/*
50 * Checks every day in a 160000 years interval centered at 1970-01-01
51 * against the expected result.
52 */
53static void time64_to_tm_test_date_range(struct kunit *test)
54{
55	/*
56	 * 80000 years	= (80000 / 400) * 400 years
57	 *		= (80000 / 400) * 146097 days
58	 *		= (80000 / 400) * 146097 * 86400 seconds
59	 */
60	time64_t total_secs = ((time64_t) 80000) / 400 * 146097 * 86400;
61	long year = 1970 - 80000;
62	int month = 1;
63	int mdday = 1;
64	int yday = 0;
65
66	struct tm result;
67	time64_t secs;
68	s64 days;
69
70	for (secs = -total_secs; secs <= total_secs; secs += 86400) {
71
72		time64_to_tm(secs, 0, &result);
73
74		days = div_s64(secs, 86400);
75
76		#define FAIL_MSG "%05ld/%02d/%02d (%2d) : %ld", \
77			year, month, mdday, yday, days
78
79		KUNIT_ASSERT_EQ_MSG(test, year - 1900, result.tm_year, FAIL_MSG);
80		KUNIT_ASSERT_EQ_MSG(test, month - 1, result.tm_mon, FAIL_MSG);
81		KUNIT_ASSERT_EQ_MSG(test, mdday, result.tm_mday, FAIL_MSG);
82		KUNIT_ASSERT_EQ_MSG(test, yday, result.tm_yday, FAIL_MSG);
83
84		advance_date(&year, &month, &mdday, &yday);
85	}
86}
87
88static struct kunit_case time_test_cases[] = {
89	KUNIT_CASE(time64_to_tm_test_date_range),
90	{}
91};
92
93static struct kunit_suite time_test_suite = {
94	.name = "time_test_cases",
95	.test_cases = time_test_cases,
96};
97
98kunit_test_suite(time_test_suite);
 
99MODULE_LICENSE("GPL");

  1// SPDX-License-Identifier: LGPL-2.1+
  2
  3#include <kunit/test.h>
  4#include <linux/time.h>
  5
  6/*
  7 * Traditional implementation of leap year evaluation.
  8 */
  9static bool is_leap(long year)
 10{
 11	return year % 4 == 0 && (year % 100 != 0 || year % 400 == 0);
 12}
 13
 14/*
 15 * Gets the last day of a month.
 16 */
 17static int last_day_of_month(long year, int month)
 18{
 19	if (month == 2)
 20		return 28 + is_leap(year);
 21	if (month == 4 || month == 6 || month == 9 || month == 11)
 22		return 30;
 23	return 31;
 24}
 25
 26/*
 27 * Advances a date by one day.
 28 */
 29static void advance_date(long *year, int *month, int *mday, int *yday)
 30{
 31	if (*mday != last_day_of_month(*year, *month)) {
 32		++*mday;
 33		++*yday;
 34		return;
 35	}
 36
 37	*mday = 1;
 38	if (*month != 12) {
 39		++*month;
 40		++*yday;
 41		return;
 42	}
 43
 44	*month = 1;
 45	*yday  = 0;
 46	++*year;
 47}
 48
 49/*
 50 * Checks every day in a 160000 years interval centered at 1970-01-01
 51 * against the expected result.
 52 */
 53static void time64_to_tm_test_date_range(struct kunit *test)
 54{
 55	/*
 56	 * 80000 years	= (80000 / 400) * 400 years
 57	 *		= (80000 / 400) * 146097 days
 58	 *		= (80000 / 400) * 146097 * 86400 seconds
 59	 */
 60	time64_t total_secs = ((time64_t) 80000) / 400 * 146097 * 86400;
 61	long year = 1970 - 80000;
 62	int month = 1;
 63	int mdday = 1;
 64	int yday = 0;
 65
 66	struct tm result;
 67	time64_t secs;
 68	s64 days;
 69
 70	for (secs = -total_secs; secs <= total_secs; secs += 86400) {
 71
 72		time64_to_tm(secs, 0, &result);
 73
 74		days = div_s64(secs, 86400);
 75
 76		#define FAIL_MSG "%05ld/%02d/%02d (%2d) : %lld", \
 77			year, month, mdday, yday, days
 78
 79		KUNIT_ASSERT_EQ_MSG(test, year - 1900, result.tm_year, FAIL_MSG);
 80		KUNIT_ASSERT_EQ_MSG(test, month - 1, result.tm_mon, FAIL_MSG);
 81		KUNIT_ASSERT_EQ_MSG(test, mdday, result.tm_mday, FAIL_MSG);
 82		KUNIT_ASSERT_EQ_MSG(test, yday, result.tm_yday, FAIL_MSG);
 83
 84		advance_date(&year, &month, &mdday, &yday);
 85	}
 86}
 87
 88static struct kunit_case time_test_cases[] = {
 89	KUNIT_CASE_SLOW(time64_to_tm_test_date_range),
 90	{}
 91};
 92
 93static struct kunit_suite time_test_suite = {
 94	.name = "time_test_cases",
 95	.test_cases = time_test_cases,
 96};
 97
 98kunit_test_suite(time_test_suite);
 99MODULE_DESCRIPTION("time unit test suite");
100MODULE_LICENSE("GPL");