reference: check for gmtime() error

Although gmtime() is expected to convert any time of the system clock at
least in the next few NTP eras, a correct code should always check the
returned value and this shouldn't be a fatal error in handling of leap
seconds.
This commit is contained in:
Miroslav Lichvar 2017-09-14 15:28:37 +02:00
parent eb51c500e8
commit 04e6474b75

View file

@ -609,7 +609,14 @@ is_offset_ok(double offset)
/* ================================================== */
static int
is_leap_second_day(struct tm *stm) {
is_leap_second_day(time_t when)
{
struct tm *stm;
stm = gmtime(&when);
if (!stm)
return 0;
/* Allow leap second only on the last day of June and December */
return (stm->tm_mon == 5 && stm->tm_mday == 30) ||
(stm->tm_mon == 11 && stm->tm_mday == 31);
@ -624,7 +631,7 @@ get_tz_leap(time_t when, int *tai_offset)
static NTP_Leap tz_leap;
static int tz_tai_offset;
struct tm stm;
struct tm stm, *tm;
time_t t;
char *tz_env, tz_orig[128];
@ -639,7 +646,11 @@ get_tz_leap(time_t when, int *tai_offset)
tz_leap = LEAP_Normal;
tz_tai_offset = 0;
stm = *gmtime(&when);
tm = gmtime(&when);
if (!tm)
return tz_leap;
stm = *tm;
/* Temporarily switch to the timezone containing leap seconds */
tz_env = getenv("TZ");
@ -784,7 +795,7 @@ update_leap_status(NTP_Leap leap, time_t now, int reset)
if (leap == LEAP_InsertSecond || leap == LEAP_DeleteSecond) {
/* Check that leap second is allowed today */
if (is_leap_second_day(gmtime(&now))) {
if (is_leap_second_day(now)) {
if (leap == LEAP_InsertSecond) {
leap_sec = 1;
} else {