How does TuyaOS report the device MAC address?

/*
*IPC 5.x useshttp_gw_ipc_custom_msg() interface
*IPC 6.x usestuya_http_gw_ipc_custom_msg()interface
*/
OPERATE_RET test_report_mac_api()
{
ty_cJSON* result = NULL;
CHAR_T buffer[32] = {0};
NW_MAC_S buffer_mac;
tal_wifi_get_mac(WF_STATION, &buffer_mac);
snprintf(buffer, sizeof(buffer), "{\"mac\":\"%02X%02X%02X%02X%02X%02X\"}",
buffer_mac.mac[0], buffer_mac.mac[1], buffer_mac.mac[2],
buffer_mac.mac[3], buffer_mac.mac[4], buffer_mac.mac[5]);
OPERATE_RET ret = tuya_http_gw_ipc_custom_msg("thing.device.mac.report", "1.0", buffer, &result);
if(result) {
ty_cJSON_Delete(result);
    }
PR_DEBUG("Upload mac %s, ret: %d", buffer, ret);
return ret;
}