mod_graylog2: additional input checks on LOG_FIELDS[]

src/mod/loggers/mod_graylog2/mod_graylog2.c

@@ -123,6 +123,7 @@ static char *to_gelf(const switch_log_node_t *node, switch_log_level_t log_level
 
 			switch_event_header_t *hp;
 			for (hp = log_fields->headers; hp; hp = hp->next) {
+				if (!zstr(hp->name) && !zstr(hp->value)) {
 					if (strncmp(hp->name, "@#", 2) == 0) {
 						field_name = switch_mprintf("_%s", hp->name + 2);
 						cJSON_AddItemToObject(gelf, field_name, cJSON_CreateNumber(strtod(hp->value, NULL)));
@@ -132,6 +133,7 @@ static char *to_gelf(const switch_log_node_t *node, switch_log_level_t log_level
 					}
 					free(field_name);
 				}
+			}
 
 			switch_event_destroy(&log_fields);
 			full_message = parsed_full_message;
@@ -149,9 +151,7 @@ static char *to_gelf(const switch_log_node_t *node, switch_log_level_t log_level
 	gelf_text = cJSON_PrintUnformatted(gelf);
 	cJSON_Delete(gelf);
 	
-	if (parsed_full_message != NULL) {
-		free(parsed_full_message);
-	}
+	switch_safe_free(parsed_full_message);
 	
 	return gelf_text;
 }