garmin: fix up some leftovers

When importing FIT files, we may not have serial numbers or firmware
versions in the result, so don't report them when they don't exist.

Also, add the product name to the FILE message field list, which can
contain relevant information.  Not that we report it right now, but now
we *could* do so.

This concludes the Suunto FIT file export saga.  It's not great, but it
looks like it should be usable.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

src/garmin_parser.c

@@ -523,6 +523,7 @@ DECLARE_FIELD(FILE, serial, UINT32Z) { }
 DECLARE_FIELD(FILE, creation_time, UINT32) { }
 DECLARE_FIELD(FILE, number, UINT16) { }
 DECLARE_FIELD(FILE, other_time, UINT32) { }
+DECLARE_FIELD(FILE, product_name, STRING) { }
 
 // SESSION msg
 DECLARE_FIELD(SESSION, start_time, UINT32)	{ garmin->dive.time = data; }
@@ -897,7 +898,7 @@ struct msg_desc {
 	static const struct msg_desc name##_msg_desc
 
 DECLARE_MESG(FILE) = {
-	.maxfield = 8,
+	.maxfield = 9,
 	.field = {
 		SET_FIELD(FILE, 0, file_type, ENUM),
 		SET_FIELD(FILE, 1, manufacturer, UINT16),
@@ -906,6 +907,7 @@ DECLARE_MESG(FILE) = {
 		SET_FIELD(FILE, 4, creation_time, UINT32),
 		SET_FIELD(FILE, 5, number, UINT16),
 		SET_FIELD(FILE, 7, other_time, UINT32),
+		SET_FIELD(FILE, 8, product_name, STRING),
 	}
 };
 
@@ -1633,9 +1635,11 @@ garmin_parser_set_data (dc_parser_t *abstract, const unsigned char *data, unsign
 	traverse_data(garmin);
 
 	// Device information
-	dc_field_add_string_fmt(&garmin->cache, "Serial", "%u", garmin->dive.serial);
-	dc_field_add_string_fmt(&garmin->cache, "Firmware", "%u.%02u",
-		garmin->dive.firmware / 100, garmin->dive.firmware % 100);
+	if (garmin->dive.serial)
+		dc_field_add_string_fmt(&garmin->cache, "Serial", "%u", garmin->dive.serial);
+	if (garmin->dive.firmware)
+		dc_field_add_string_fmt(&garmin->cache, "Firmware", "%u.%02u",
+			garmin->dive.firmware / 100, garmin->dive.firmware % 100);
 
 	// These seem to be the "real" GPS dive coordinates
 	add_gps_string(garmin, "GPS1", &garmin->gps.SESSION.entry);