Windows reference code: improvements for composite devices

Author: manuelbl

reference/windows/USB/usb_device.cpp

@@ -22,8 +22,8 @@
 #include <regex>
 #include <thread>
 
-usb_device::usb_device(usb_registry* registry, std::wstring&& device_path, int vendor_id, int product_id, const std::vector<uint8_t>& config_desc)
-: registry_(registry), vendor_id_(vendor_id), product_id_(product_id), is_open_(false), device_path_(std::move(device_path)) {
+usb_device::usb_device(usb_registry* registry, std::wstring&& device_path, int vendor_id, int product_id, const std::vector<uint8_t>& config_desc, bool is_composite)
+: registry_(registry), vendor_id_(vendor_id), product_id_(product_id), is_open_(false), device_path_(std::move(device_path)), is_composite_(is_composite) {
 
     config_parser parser{};
     parser.parse(config_desc.data(), static_cast<int>(config_desc.size()));
@@ -458,7 +458,7 @@ void usb_device::cancel_transfer(usb_direction direction, int endpoint_number, O
 }
 
 std::wstring usb_device::get_interface_device_path(int interface_num) {
-    if (interface_num == 0)
+    if (!is_composite_)
         return device_path_;
 
     auto it = interface_device_paths_.find(interface_num);
@@ -471,9 +471,6 @@ std::wstring usb_device::get_interface_device_path(int interface_num) {
 
         auto dev_info_set = device_info_set::of_path(device_path_);
 
-        if (!dev_info_set.is_composite_device())
-            throw usb_error("internal error: interface belongs to a separate function but device is not composite");
-
         auto children_instance_ids = dev_info_set.get_device_property_string_list(DEVPKEY_Device_Children);
         if (children_instance_ids.empty()) {
             std::wcerr << "missing children IDs for device " << device_path_ << std::endl;

reference/windows/USB/usb_device.hpp

@@ -248,7 +248,7 @@ class usb_device {
         interface_handle(int intf_num, int first_num, std::wstring&& path);
     };
 
-    usb_device(usb_registry* registry, std::wstring&& device_path, int vendor_id, int product_id, const std::vector<uint8_t>& config_desc);
+    usb_device(usb_registry* registry, std::wstring&& device_path, int vendor_id, int product_id, const std::vector<uint8_t>& config_desc, bool is_composite);
     void set_product_names(const std::string& manufacturer, const std::string& product, const std::string& serial_number);
     void build_handles(const std::wstring& device_path);
     std::wstring get_interface_device_path(int interface_num);
@@ -285,6 +285,7 @@ class usb_device {
     std::string product_;
     std::string serial_number_;
 
+    bool is_composite_;
     std::vector<usb_interface> interfaces_;
     std::vector<usb_composite_function> functions_;
     std::vector<interface_handle> interface_handles_;

reference/windows/USB/usb_registry.cpp

@@ -167,10 +167,10 @@ std::shared_ptr<usb_device> usb_registry::create_device_from_device_info(device_
         hub_handles[hub_path] = hub_handle;
     }
 
-    return create_device(std::move(device_path), hub_handle, usb_port_num);
+    return create_device(std::move(device_path), dev_info_set.is_composite_device(), hub_handle, usb_port_num);
 }
 
-std::shared_ptr<usb_device> usb_registry::create_device(std::wstring&& device_path, HANDLE hub_handle, DWORD usb_port_num) {
+std::shared_ptr<usb_device> usb_registry::create_device(std::wstring&& device_path, bool is_composite, HANDLE hub_handle, DWORD usb_port_num) {
 
     // get device descriptor
     USB_NODE_CONNECTION_INFORMATION_EX conn_info = { 0 };
@@ -186,7 +186,7 @@ std::shared_ptr<usb_device> usb_registry::create_device(std::wstring&& device_pa
     auto config_desc = get_descriptor(hub_handle, usb_port_num, USB_CONFIGURATION_DESCRIPTOR_TYPE, 0, 0);
 
     // Create new device
-    std::shared_ptr<usb_device> device(new usb_device(this, std::move(device_path), vendorId, productId, config_desc));
+    std::shared_ptr<usb_device> device(new usb_device(this, std::move(device_path), vendorId, productId, config_desc, is_composite));
     device->set_product_names(
         get_string(hub_handle, usb_port_num, conn_info.DeviceDescriptor.iManufacturer),
         get_string(hub_handle, usb_port_num, conn_info.DeviceDescriptor.iProduct),

reference/windows/USB/usb_registry.hpp

@@ -53,7 +53,7 @@ class usb_registry {
 
     void detect_present_devices();
     std::shared_ptr<usb_device> create_device_from_device_info(device_info_set& dev_info_set, std::wstring&& device_path, std::map<std::wstring, HANDLE>& hub_handles);
-    std::shared_ptr<usb_device> create_device(std::wstring&& device_path, HANDLE hub_handle, DWORD usb_port_num);
+    std::shared_ptr<usb_device> create_device(std::wstring&& device_path, bool is_composite, HANDLE hub_handle, DWORD usb_port_num);
 
     static std::string get_string(HANDLE hub_handle, ULONG usb_port_num, int index);
     static std::vector<uint8_t> get_descriptor(HANDLE hub_handle, ULONG usb_port_num, uint16_t descriptor_type, int index, int language_id, int request_size = 0);