shell: date_service: make clear that leap seconds are not supported

SYS_CLOCK_REALTIME is following Unix time so, even if tm_sec == 60 is accepted,
make very clear that leap seconds are not supported.

Signed-off-by: Diego Herranz <[email protected]>

Author: diegoherranz

subsys/shell/modules/date_service.c

@@ -123,12 +123,17 @@ static int get_h_m_s(const struct shell *sh, struct tm *t, char *time_str)
 		return -EINVAL;
 	}
 
-	/* Note range allows for a leap second */
+	/* Note range allows for a leap second, even if not supported */
 	if ((t->tm_sec < 0) || (t->tm_sec > 60)) {
 		shell_error(sh, "Invalid second");
 		return -EINVAL;
 	}
 
+	if (t->tm_sec == 60) {
+		shell_warn(sh, "Leap seconds not supported in Unix time, "
+			       "so time actually set will be off by 1 second.");
+	}
+
 	return 0;
 }