From 61a7e57d8608052a050795c1620f1e918ab80a31 Mon Sep 17 00:00:00 2001 From: Benoit Bolsee Date: Wed, 5 Jul 2017 12:57:16 +0200 Subject: 04.08: find a portable way to obtain the timezone offset Portable GMT offset calculation to display correct time on GSM. Change-Id: I673f17af2550c9708c4771e4ea4eafbbfafbb824 --- openbsc/src/libmsc/gsm_04_08.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) (limited to 'openbsc/src/libmsc') diff --git a/openbsc/src/libmsc/gsm_04_08.c b/openbsc/src/libmsc/gsm_04_08.c index 89108e466..f92622334 100644 --- a/openbsc/src/libmsc/gsm_04_08.c +++ b/openbsc/src/libmsc/gsm_04_08.c @@ -861,12 +861,19 @@ int gsm48_tx_mm_info(struct gsm_subscriber_connection *conn) else { /* Need to get GSM offset and convert into 15 min units */ /* This probably breaks if gmtoff returns a value not evenly divisible by 15? */ - local_time = localtime(&cur_t); #ifdef HAVE_TM_GMTOFF_IN_TM + local_time = localtime(&cur_t); tzunits = (local_time->tm_gmtoff/60)/15; #else -#warning find a portable way to obtain the timezone offset - tzunits = 0; + /* find timezone offset */ + time_t utc; + double offsetFromUTC; + utc = mktime(gmt_time); + local_time = localtime(&cur_t); + offsetFromUTC = difftime(cur_t, utc); + if (local_time->tm_isdst) + offsetFromUTC += 3600.0; + tzunits = ((int)offsetFromUTC) / 60 / 15; #endif if (tzunits < 0) { tzunits = tzunits/-1; -- cgit v1.2.3