Function dynamic_connect

src/main.c:198–232

* @brief Checks if an existing connection exists, and either uses it, or closes it and creates a new one * * A device - depending on the feature - needs different Endpoints/Connections * Instead of opening and keeping track of multiple connections, we close and open connections no demand * * * * @param existing_hid_path an existing connection path or NULL if none yet * @param device_handle

 * @return hid_device pointer if successful, or NULL (error in hid_error)
 */
static hid_device* dynamic_connect(char** existing_hid_path, hid_device* device_handle,
    struct device* device, enum capabilities cap)
{
    // Generate the path which is needed
    char* hid_path = get_hid_path(device->idVendor, device->idProduct,
        device->capability_details[cap].interface, device->capability_details[cap].usagepage, device->capability_details[cap].usageid);

    if (!hid_path) {
        return NULL;
    }

    // A connection already exists
    if (device_handle != NULL) {
        // The connection which exists is the same we need, so simply return it
        if (strcmp(*existing_hid_path, hid_path) == 0) {
            return device_handle;
        } else { // if its not the same, and already one connection is open, close it so we can make a new one
            hid_close(device_handle);
        }
    }

    free(*existing_hid_path);

    device_handle = hid_open_path(hid_path);
    if (device_handle == NULL) {
        *existing_hid_path = NULL;
        return NULL;
    }

    hid_get_manufacturer_string(device_handle, device->device_hid_vendorname, sizeof(device->device_hid_vendorname) / sizeof(device->device_hid_vendorname[0]));
    hid_get_product_string(device_handle, device->device_hid_productname, sizeof(device->device_hid_productname) / sizeof(device->device_hid_productname[0]));

    *existing_hid_path = hid_path;
    return device_handle;
}

/**
 * @brief Handle a requested feature