From 41071737d02a92b64de0d83b3cd2c9d4cabecb37 Mon Sep 17 00:00:00 2001
From: Denis Kenzior <denkenz@gmail.com>
Date: Fri, 5 Jun 2009 11:51:46 -0500
Subject: [PATCH] Add utility to convert SCTS to local/remote time

---
 src/smsutil.c   | 37 +++++++++++++++++++++++++++++++++++++
 src/smsutil.h   |  2 ++
 unit/test-sms.c | 16 ++++++++++++++++
 3 files changed, 55 insertions(+)

diff --git a/src/smsutil.c b/src/smsutil.c
index 6bbb57d..d44e73d 100644
--- a/src/smsutil.c
+++ b/src/smsutil.c
@@ -1484,3 +1484,40 @@ gboolean sms_udh_iter_next(struct sms_udh_iter *iter)
 
 	return TRUE;
 }
+
+/* Returns both forms of time.  The time_t value returns the time in local
+ * timezone.  The struct tm is filled out with the remote time information
+ */
+time_t sms_scts_to_time(struct sms_scts *scts, struct tm *remote)
+{
+	struct tm t;
+	time_t ret;
+
+	t.tm_sec = scts->second;
+	t.tm_min = scts->minute;
+	t.tm_hour = scts->hour;
+	t.tm_mday = scts->day;
+	t.tm_mon = scts->month - 1;
+	t.tm_isdst = -1;
+
+	if (scts->year > 80)
+		t.tm_year = scts->year;
+	else
+		t.tm_year = scts->year + 100;
+
+	ret = mktime(&t);
+
+	/* Adjust local time by the local timezone information */
+	ret += t.tm_gmtoff;
+
+	/* Set the proper timezone on the remote side */
+	t.tm_gmtoff = scts->timezone * 15 * 60;
+
+	/* Now adjust by the remote timezone information */
+	ret -= t.tm_gmtoff;
+
+	if (remote)
+		memcpy(remote, &t, sizeof(struct tm));
+
+	return ret;
+}
diff --git a/src/smsutil.h b/src/smsutil.h
index 940a185..566701c 100644
--- a/src/smsutil.h
+++ b/src/smsutil.h
@@ -295,4 +295,6 @@ guint8 sms_udh_iter_get_ie_length(struct sms_udh_iter *iter);
 void sms_udh_iter_get_ie_data(struct sms_udh_iter *iter, guint8 *data);
 gboolean sms_udh_iter_has_next(struct sms_udh_iter *iter);
 gboolean sms_udh_iter_next(struct sms_udh_iter *iter);
+
+time_t sms_scts_to_time(struct sms_scts *scts, struct tm *remote);
 #endif
diff --git a/unit/test-sms.c b/unit/test-sms.c
index d644cda..6057076 100644
--- a/unit/test-sms.c
+++ b/unit/test-sms.c
@@ -38,6 +38,10 @@ static const char *simple_submit = "0011000B916407281553F80000AA"
 
 static void print_scts(struct sms_scts *scts, const char *prefix)
 {
+	time_t ts;
+	struct tm remote;
+	char buf[128];
+
 	g_print("%s: (YY-MM-DD) %02d-%02d-%02d\n", prefix,
 		(int)scts->year, (int)scts->month, (int)scts->day);
 
@@ -47,6 +51,18 @@ static void print_scts(struct sms_scts *scts, const char *prefix)
 	g_print("%s: Timezone %d hours %d minutes\n", prefix,
 		(int)scts->timezone / 4,
 		(int)((abs(scts->timezone) % 4) * 15));
+
+	ts = sms_scts_to_time(scts, &remote);
+
+	strftime(buf, 127, "%a, %d %b %Y %H:%M:%S %z", localtime(&ts));
+	buf[127] = '\0';
+
+	g_print("local time: %s\n", buf);
+
+	strftime(buf, 127, "%a, %d %b %Y %H:%M:%S %z", &remote);
+	buf[127] = '\0';
+
+	g_print("remote time: %s\n", buf);
 }
 
 static void print_vpf(enum sms_validity_period_format vpf,
-- 
2.7.4