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, but note that long 8 * is a signed type and the tests do cover negative year values. So this 9 * can't use the is_leap_year() helper from rtc.h. 10 */ 11 static bool is_leap(long year) 12 { 13 return year % 4 == 0 && (year % 100 != 0 || year % 400 == 0); 14 } 15 16 /* 17 * Gets the last day of a month. 18 */ 19 static int last_day_of_month(long year, int month) 20 { 21 if (month == 2) 22 return 28 + is_leap(year); 23 if (month == 4 || month == 6 || month == 9 || month == 11) 24 return 30; 25 return 31; 26 } 27 28 /* 29 * Advances a date by one day. 30 */ 31 static void advance_date(long *year, int *month, int *mday, int *yday) 32 { 33 if (*mday != last_day_of_month(*year, *month)) { 34 ++*mday; 35 ++*yday; 36 return; 37 } 38 39 *mday = 1; 40 if (*month != 12) { 41 ++*month; 42 ++*yday; 43 return; 44 } 45 46 *month = 1; 47 *yday = 0; 48 ++*year; 49 } 50 51 /* 52 * Checks every day in a 160000 years interval centered at 1970-01-01 53 * against the expected result. 54 */ 55 static void time64_to_tm_test_date_range(struct kunit *test) 56 { 57 /* 58 * 80000 years = (80000 / 400) * 400 years 59 * = (80000 / 400) * 146097 days 60 * = (80000 / 400) * 146097 * 86400 seconds 61 */ 62 time64_t total_secs = ((time64_t) 80000) / 400 * 146097 * 86400; 63 long year = 1970 - 80000; 64 int month = 1; 65 int mdday = 1; 66 int yday = 0; 67 68 struct tm result; 69 time64_t secs; 70 s64 days; 71 72 for (secs = -total_secs; secs <= total_secs; secs += 86400) { 73 74 time64_to_tm(secs, 0, &result); 75 76 days = div_s64(secs, 86400); 77 78 #define FAIL_MSG "%05ld/%02d/%02d (%2d) : %lld", \ 79 year, month, mdday, yday, days 80 81 KUNIT_ASSERT_EQ_MSG(test, year - 1900, result.tm_year, FAIL_MSG); 82 KUNIT_ASSERT_EQ_MSG(test, month - 1, result.tm_mon, FAIL_MSG); 83 KUNIT_ASSERT_EQ_MSG(test, mdday, result.tm_mday, FAIL_MSG); 84 KUNIT_ASSERT_EQ_MSG(test, yday, result.tm_yday, FAIL_MSG); 85 86 advance_date(&year, &month, &mdday, &yday); 87 } 88 } 89 90 static struct kunit_case time_test_cases[] = { 91 KUNIT_CASE_SLOW(time64_to_tm_test_date_range), 92 {} 93 }; 94 95 static struct kunit_suite time_test_suite = { 96 .name = "time_test_cases", 97 .test_cases = time_test_cases, 98 }; 99 100 kunit_test_suite(time_test_suite); 101 MODULE_DESCRIPTION("time unit test suite"); 102 MODULE_LICENSE("GPL"); 103