test_rtc_lib.c

  1// SPDX-License-Identifier: LGPL-2.1+
  2
  3#include <kunit/test.h>
  4#include <linux/rtc.h>
  5
  6/*
  7 * Advance a date by one day.
  8 */
  9static void advance_date(int *year, int *month, int *mday, int *yday, int *wday)
 10{
 11	*wday = (*wday + 1) % 7;
 12
 13	if (*mday != rtc_month_days(*month - 1, *year)) {
 14		++*mday;
 15		++*yday;
 16		return;
 17	}
 18
 19	*mday = 1;
 20	if (*month != 12) {
 21		++*month;
 22		++*yday;
 23		return;
 24	}
 25
 26	*month = 1;
 27	*yday  = 1;
 28	++*year;
 29}
 30
 31/*
 32 * Check every day in specified number of years interval starting on 1970-01-01
 33 * against the expected result.
 34 */
 35static void rtc_time64_to_tm_test_date_range(struct kunit *test, int years)
 36{
 37	/*
 38	 * years	= (years / 400) * 400 years
 39	 *		= (years / 400) * 146097 days
 40	 *		= (years / 400) * 146097 * 86400 seconds
 41	 */
 42	time64_t total_secs = ((time64_t)years) / 400 * 146097 * 86400;
 43
 44	int year	= 1900;
 45	int month	= 1;
 46	int mday	= 1;
 47	int yday	= 1;
 48	int wday	= 1; /* Jan 1st 1900 was a Monday */
 49
 50	struct rtc_time result;
 51	time64_t secs;
 52	const time64_t sec_offset = RTC_TIMESTAMP_BEGIN_1900 + ((1 * 60) + 2) * 60 + 3;
 53
 54	for (secs = 0; secs <= total_secs; secs += 86400) {
 55
 56		rtc_time64_to_tm(secs + sec_offset, &result);
 57
 58		#define FAIL_MSG "%d/%02d/%02d (%2d, %d) : %lld", \
 59			year, month, mday, yday, wday, secs + sec_offset
 60
 61		KUNIT_ASSERT_EQ_MSG(test, year - 1900, result.tm_year, FAIL_MSG);
 62		KUNIT_ASSERT_EQ_MSG(test, month - 1, result.tm_mon, FAIL_MSG);
 63		KUNIT_ASSERT_EQ_MSG(test, mday, result.tm_mday, FAIL_MSG);
 64		KUNIT_ASSERT_EQ_MSG(test, yday, result.tm_yday, FAIL_MSG);
 65		KUNIT_ASSERT_EQ_MSG(test, 1, result.tm_hour, FAIL_MSG);
 66		KUNIT_ASSERT_EQ_MSG(test, 2, result.tm_min, FAIL_MSG);
 67		KUNIT_ASSERT_EQ_MSG(test, 3, result.tm_sec, FAIL_MSG);
 68		KUNIT_ASSERT_EQ_MSG(test, wday, result.tm_wday, FAIL_MSG);
 69
 70		advance_date(&year, &month, &mday, &yday, &wday);
 71	}
 72}
 73
 74/*
 75 * Checks every day in a 160000 years interval starting on 1900-01-01
 76 * against the expected result.
 77 */
 78static void rtc_time64_to_tm_test_date_range_160000(struct kunit *test)
 79{
 80	rtc_time64_to_tm_test_date_range(test, 160000);
 81}
 82
 83/*
 84 * Checks every day in a 1000 years interval starting on 1900-01-01
 85 * against the expected result.
 86 */
 87static void rtc_time64_to_tm_test_date_range_1000(struct kunit *test)
 88{
 89	rtc_time64_to_tm_test_date_range(test, 1000);
 90}
 91
 92static struct kunit_case rtc_lib_test_cases[] = {
 93	KUNIT_CASE(rtc_time64_to_tm_test_date_range_1000),
 94	KUNIT_CASE_SLOW(rtc_time64_to_tm_test_date_range_160000),
 95	{}
 96};
 97
 98static struct kunit_suite rtc_lib_test_suite = {
 99	.name = "rtc_lib_test_cases",
100	.test_cases = rtc_lib_test_cases,
101};
102
103kunit_test_suite(rtc_lib_test_suite);
104
105MODULE_DESCRIPTION("KUnit test for RTC lib functions");
106MODULE_LICENSE("GPL");