time: Add time64_to_tm()

time_to_tm() takes time_t as an argument.
time_t is not y2038 safe.
Add time64_to_tm() that takes time64_t as an argument
which is y2038 safe.
The plan is to eventually replace all calls to time_to_tm()
by time64_to_tm().

Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
This commit is contained in:
Deepa Dinamani 2016-06-08 22:04:59 -07:00 committed by John Stultz
parent af4afb4008
commit e6c2682a1d
2 changed files with 20 additions and 6 deletions

View File

@ -205,7 +205,20 @@ struct tm {
int tm_yday;
};
void time_to_tm(time_t totalsecs, int offset, struct tm *result);
void time64_to_tm(time64_t totalsecs, int offset, struct tm *result);
/**
* time_to_tm - converts the calendar time to local broken-down time
*
* @totalsecs the number of seconds elapsed since 00:00:00 on January 1, 1970,
* Coordinated Universal Time (UTC).
* @offset offset seconds adding to totalsecs.
* @result pointer to struct tm variable to receive broken-down time
*/
static inline void time_to_tm(time_t totalsecs, int offset, struct tm *result)
{
time64_to_tm(totalsecs, offset, result);
}
/**
* timespec_to_ns - Convert timespec to nanoseconds

View File

@ -67,20 +67,21 @@ static const unsigned short __mon_yday[2][13] = {
#define SECS_PER_DAY (SECS_PER_HOUR * 24)
/**
* time_to_tm - converts the calendar time to local broken-down time
* time64_to_tm - converts the calendar time to local broken-down time
*
* @totalsecs the number of seconds elapsed since 00:00:00 on January 1, 1970,
* Coordinated Universal Time (UTC).
* @offset offset seconds adding to totalsecs.
* @result pointer to struct tm variable to receive broken-down time
*/
void time_to_tm(time_t totalsecs, int offset, struct tm *result)
void time64_to_tm(time64_t totalsecs, int offset, struct tm *result)
{
long days, rem, y;
int remainder;
const unsigned short *ip;
days = totalsecs / SECS_PER_DAY;
rem = totalsecs % SECS_PER_DAY;
days = div_s64_rem(totalsecs, SECS_PER_DAY, &remainder);
rem = remainder;
rem += offset;
while (rem < 0) {
rem += SECS_PER_DAY;
@ -124,4 +125,4 @@ void time_to_tm(time_t totalsecs, int offset, struct tm *result)
result->tm_mon = y;
result->tm_mday = days + 1;
}
EXPORT_SYMBOL(time_to_tm);
EXPORT_SYMBOL(time64_to_tm);