original_kernel/kernel/time/time_test.c

100 lines
2.0 KiB
C

// SPDX-License-Identifier: LGPL-2.1+
#include <kunit/test.h>
#include <linux/time.h>
/*
* Traditional implementation of leap year evaluation.
*/
static bool is_leap(long year)
{
return year % 4 == 0 && (year % 100 != 0 || year % 400 == 0);
}
/*
* Gets the last day of a month.
*/
static int last_day_of_month(long year, int month)
{
if (month == 2)
return 28 + is_leap(year);
if (month == 4 || month == 6 || month == 9 || month == 11)
return 30;
return 31;
}
/*
* Advances a date by one day.
*/
static void advance_date(long *year, int *month, int *mday, int *yday)
{
if (*mday != last_day_of_month(*year, *month)) {
++*mday;
++*yday;
return;
}
*mday = 1;
if (*month != 12) {
++*month;
++*yday;
return;
}
*month = 1;
*yday = 0;
++*year;
}
/*
* Checks every day in a 160000 years interval centered at 1970-01-01
* against the expected result.
*/
static void time64_to_tm_test_date_range(struct kunit *test)
{
/*
* 80000 years = (80000 / 400) * 400 years
* = (80000 / 400) * 146097 days
* = (80000 / 400) * 146097 * 86400 seconds
*/
time64_t total_secs = ((time64_t) 80000) / 400 * 146097 * 86400;
long year = 1970 - 80000;
int month = 1;
int mdday = 1;
int yday = 0;
struct tm result;
time64_t secs;
s64 days;
for (secs = -total_secs; secs <= total_secs; secs += 86400) {
time64_to_tm(secs, 0, &result);
days = div_s64(secs, 86400);
#define FAIL_MSG "%05ld/%02d/%02d (%2d) : %ld", \
year, month, mdday, yday, days
KUNIT_ASSERT_EQ_MSG(test, year - 1900, result.tm_year, FAIL_MSG);
KUNIT_ASSERT_EQ_MSG(test, month - 1, result.tm_mon, FAIL_MSG);
KUNIT_ASSERT_EQ_MSG(test, mdday, result.tm_mday, FAIL_MSG);
KUNIT_ASSERT_EQ_MSG(test, yday, result.tm_yday, FAIL_MSG);
advance_date(&year, &month, &mdday, &yday);
}
}
static struct kunit_case time_test_cases[] = {
KUNIT_CASE_SLOW(time64_to_tm_test_date_range),
{}
};
static struct kunit_suite time_test_suite = {
.name = "time_test_cases",
.test_cases = time_test_cases,
};
kunit_test_suite(time_test_suite);
MODULE_LICENSE("GPL");