tests: lib: date_time: Tests for scheduled updates

Adding tests for scheduled date-time updates verifying that they occur
at configured intervals.

Some small clean-up and additional logging into date-time library.

Branch coverage is going from ~44% to ~98% having 3 branches untested.
These are related to failure of clock_gettime/clock_settime
which cannot really be achieved without creating a different test set
and mocking those APIs.

With default configuration, the tests run almost 30s due to
update intervals that we need to wait.

Jira: NCSDK-28887

Signed-off-by: Tommi Rantanen <[email protected]>

doc/nrf/libraries/others/date_time.rst

@@ -57,6 +57,14 @@ See the API documentation for more information on these functions.
    If an application has time-dependent operations immediately after connecting to the LTE network, it should wait for a confirmation indicating that time has been updated.
    If the :kconfig:option:`CONFIG_DATE_TIME_AUTO_UPDATE` option is not set, the first date-time update cycle (after boot) does not occur until the time set by the :kconfig:option:`CONFIG_DATE_TIME_UPDATE_INTERVAL_SECONDS` option has elapsed.
 
+.. note::
+
+   Exceptions to the regular date-time update interval set by the :kconfig:option:`CONFIG_DATE_TIME_UPDATE_INTERVAL_SECONDS` Kconfig option occur when
+   the :c:func:`date_time_update_async` function is called and a new date-time update is triggered and scheduled.
+   Either retry or regular update interval is used depending on the outcome of the date-time update procedure.
+   Date-time update from modem through an ``AT%XTIME`` notification,
+   or from the client through the :c:func:`date_time_set` function does not disturb the regular update interval.
+
 Configuration
 *************
 

lib/date_time/date_time_core.c

@@ -59,11 +59,18 @@ static void date_time_core_notify_event(enum date_time_evt_type time_source)
 
 	if (app_evt_handler != NULL) {
 		app_evt_handler(&evt);
+	} else {
+		LOG_DBG("No date-time event handler registered");
 	}
 }
 
 static int date_time_core_schedule_work(int interval)
 {
+	if (!IS_ENABLED(CONFIG_DATE_TIME_MODEM) && !IS_ENABLED(CONFIG_DATE_TIME_NTP)) {
+		LOG_DBG("Skipping requested date time update, modem and NTP are disabled");
+		return -ENOTSUP;
+	}
+
 	/* If a scheduled update is blocking reschedules, exit.
 	 * Otherwise set the reschedule_blocked flag to true, then proceed with the reschedule.
 	 */
@@ -104,10 +111,11 @@ static void date_time_core_schedule_retry(void)
 		return;
 	}
 
-	if (date_time_core_schedule_work(CONFIG_DATE_TIME_RETRY_INTERVAL_SECONDS) == 0) {
-		LOG_DBG("Date time update retry in: %d seconds",
-			CONFIG_DATE_TIME_RETRY_INTERVAL_SECONDS);
-	}
+	/* Scheduling new update cannot fail because we are never doing retries
+	 * if we have fresh enough time
+	 */
+	date_time_core_schedule_work(CONFIG_DATE_TIME_RETRY_INTERVAL_SECONDS);
+	LOG_DBG("Date time update retry in: %d seconds", CONFIG_DATE_TIME_RETRY_INTERVAL_SECONDS);
 }
 
 static void date_time_update_work_fn(struct k_work *work)
@@ -169,6 +177,8 @@ void date_time_lte_ind_handler(const struct lte_lc_evt *const evt)
 		case LTE_LC_NW_REG_REGISTERED_HOME:
 		case LTE_LC_NW_REG_REGISTERED_ROAMING:
 			if (!date_time_is_valid()) {
+				LOG_DBG("Date time update scheduled in 1 second "
+					"due to LTE registration");
 				k_work_reschedule_for_queue(
 					&date_time_work_q,
 					&date_time_update_work,
@@ -241,6 +251,8 @@ int date_time_core_now_local(int64_t *local_time_ms)
 
 int date_time_core_update_async(date_time_evt_handler_t evt_handler)
 {
+	LOG_DBG("Requesting date-time update asynchronously");
+
 	if (evt_handler) {
 		app_evt_handler = evt_handler;
 	} else if (app_evt_handler == NULL) {

lib/date_time/date_time_modem.c

@@ -76,7 +76,7 @@ int date_time_modem_get(int64_t *date_time_ms, int *date_time_tz)
 	/* Want to match 6 or 7 args */
 	if (rc != 6 && rc != 7) {
 		LOG_WRN("Did not get time from cellular network (error: %d). "
-			"This is normal as some cellular networks don't provide it or "
+			"This may be normal as some cellular networks don't provide it or "
 			"time may not be available yet.", rc);
 		return -ENODATA;
 	}
@@ -125,9 +125,6 @@ static void date_time_at_xtime_handler(const char *notif)
 	int err;
 	int tz;
 
-	if (notif == NULL) {
-		return;
-	}
 	modem_valid_network_time = true;
 
 	/* Check if current time is valid */
@@ -163,7 +160,8 @@ static void date_time_at_xtime_handler(const char *notif)
 	time_buf_len = hex2bin(time_str_start, 14, time_buf, sizeof(time_buf));
 
 	if (time_buf_len < sizeof(time_buf)) {
-		LOG_ERR("%%XTIME notification decoding failed (ret=%d): %s", time_buf_len, notif);
+		LOG_ERR("Time value decoding failed from %%XTIME notification (ret=%d): %s",
+			time_buf_len, notif);
 		return;
 	}
 
@@ -174,6 +172,12 @@ static void date_time_at_xtime_handler(const char *notif)
 	date_time.tm_min  = semioctet_to_dec(time_buf[4]);
 	date_time.tm_sec  = semioctet_to_dec(time_buf[5]);
 
+	/* 3GPP TS 23.040 Section 9.2.3.11 says about the time zone as follows:
+	 * The Time Zone indicates the difference, expressed in quarters of an hour,
+	 * between the local time and GMT. In the first of the two semi octets,
+	 * the first bit (bit 3 of the seventh octet of the TP Service Centre Time Stamp field)
+	 * represents the algebraic sign of this difference (0: positive, 1: negative).
+	 */
 	tz = semioctet_to_dec(time_buf[6] & 0xF7);
 	if (time_buf[6] & 0x08) {
 		tz = -tz;
@@ -238,9 +242,13 @@ void date_time_modem_xtime_subscribe_work_fn(struct k_work *work_item)
 	}
 }
 
+#if defined(CONFIG_UNITY)
+void date_time_modem_on_cfun(int mode, void *ctx)
+#else
 NRF_MODEM_LIB_ON_CFUN(date_time_cfun_hook, date_time_modem_on_cfun, NULL);
 
 static void date_time_modem_on_cfun(int mode, void *ctx)
+#endif
 {
 	ARG_UNUSED(ctx);
 

tests/lib/date_time/prj.conf

@@ -14,6 +14,11 @@ CONFIG_MOCK_NRF_MODEM_AT=y
 CONFIG_LTE_LINK_CONTROL=y
 CONFIG_POSIX_API=y
 
+CONFIG_DATE_TIME_UPDATE_INTERVAL_SECONDS=3
+CONFIG_DATE_TIME_TOO_OLD_SECONDS=1
+CONFIG_DATE_TIME_RETRY_COUNT=2
+CONFIG_DATE_TIME_RETRY_INTERVAL_SECONDS=1
+
 # Enable logs if you want to explore them
 CONFIG_LOG=n
 CONFIG_DATE_TIME_LOG_LEVEL_DBG=n