Windows: more composite device handling improvements

Author: manuelbl

java-does-usb/pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>net.codecrete.usb</groupId>
     <artifactId>java-does-usb</artifactId>
-    <version>0.6.0</version>
+    <version>0.6.1-SNAPSHOT</version>
 
     <properties>
         <maven.compiler.source>21</maven.compiler.source>

java-does-usb/src/main/java/net/codecrete/usb/windows/WindowsUSBDevice.java

@@ -49,7 +49,13 @@ public class WindowsUSBDevice extends USBDeviceImpl {
     private static final int SUCCESS = 2;
 
     private final WindowsAsyncTask asyncTask;
+    /**
+     *  Indicates if the device is a composite device
+     */
+    private final boolean isComposite;
+
     private List<InterfaceHandle> interfaceHandles;
+
     // device paths by interface number (first interface of function)
     private Map<Integer, String> devicePaths;
 
@@ -59,9 +65,12 @@ public class WindowsUSBDevice extends USBDeviceImpl {
      */
     private boolean showAsOpen;
 
-    WindowsUSBDevice(String devicePath, int vendorId, int productId, MemorySegment configDesc) {
+    WindowsUSBDevice(String devicePath, int vendorId, int productId, MemorySegment configDesc, boolean isComposite) {
         super(devicePath, vendorId, productId);
         asyncTask = WindowsAsyncTask.INSTANCE;
+        this.isComposite = isComposite;
+        if (isComposite)
+            devicePaths = new HashMap<>();
         readDescription(configDesc);
     }
 
@@ -238,14 +247,7 @@ public synchronized void releaseInterface(int interfaceNumber) {
             WinUSB.WinUsb_Free(firstIntfHandle.winusbHandle);
             firstIntfHandle.winusbHandle = null;
 
-            var path = (String)getUniqueId();
-            if (firstIntfHandle.interfaceNumber != 0) {
-                if (devicePaths != null)
-                    path = devicePaths.get(firstIntfHandle.interfaceNumber);
-                else
-                    path = null;
-            }
-            LOG.log(DEBUG, "closing device {0}", path);
+            LOG.log(DEBUG, "closing device {0}", getCachedInterfaceDevicePath(interfaceNumber));
 
             Kernel32.CloseHandle(firstIntfHandle.deviceHandle);
             firstIntfHandle.deviceHandle = null;
@@ -516,20 +518,13 @@ private InterfaceHandle findControlTransferInterface(USBControlTransfer setup) {
     }
 
     private String getInterfaceDevicePath(int interfaceNumber) {
-        var parentDevicePath = (String) getUniqueId(); // device path is id
-        if (interfaceNumber == 0)
-            return parentDevicePath;
-
-        if (devicePaths != null) {
-            var devicePath = devicePaths.get(interfaceNumber);
-            if (devicePath != null)
-                return devicePath;
-        }
+        var devicePath = getCachedInterfaceDevicePath(interfaceNumber);
+        if (devicePath != null)
+            return devicePath;
 
-        try (var deviceInfoSet = DeviceInfoSet.ofPath(parentDevicePath)) {
-            if (!deviceInfoSet.isCompositeDevice())
-                throwException("internal error: interface belongs to a composite function but device is not composite");
+        var parentDevicePath = (String) getUniqueId();
 
+        try (var deviceInfoSet = DeviceInfoSet.ofPath(parentDevicePath)) {
             var childrenInstanceIDs = deviceInfoSet.getStringListProperty(Children);
             if (childrenInstanceIDs == null) {
                 LOG.log(DEBUG, "missing children instance IDs for device {0}", parentDevicePath);
@@ -551,6 +546,12 @@ private String getInterfaceDevicePath(int interfaceNumber) {
         return null; // retry later
     }
 
+    private String getCachedInterfaceDevicePath(int interfaceNumber) {
+        if (!isComposite)
+            return (String) getUniqueId();
+        return devicePaths.get(interfaceNumber);
+    }
+
     private int fetchChildDevicePath(String instanceId, int interfaceNumber) {
         try (var deviceInfoSet = DeviceInfoSet.ofInstance(instanceId)) {
 

java-does-usb/src/main/java/net/codecrete/usb/windows/WindowsUSBDeviceRegistry.java

@@ -174,7 +174,7 @@ private USBDevice createDeviceFromDeviceInfo(DeviceInfoSet deviceInfoSet, String
                 hubHandles.put(hubPath, hubHandle);
             }
 
-            return createDevice(devicePath, hubHandle, usbPortNum);
+            return createDevice(devicePath, deviceInfoSet.isCompositeDevice(), hubHandle, usbPortNum);
         }
     }
 
@@ -186,7 +186,7 @@ private USBDevice createDeviceFromDeviceInfo(DeviceInfoSet deviceInfoSet, String
      * @param usbPortNum the USB port number
      * @return the {@code USBDevice} instance
      */
-    private USBDevice createDevice(String devicePath, MemorySegment hubHandle, int usbPortNum) {
+    private USBDevice createDevice(String devicePath, boolean isComposite, MemorySegment hubHandle, int usbPortNum) {
 
         try (var arena = Arena.ofConfined()) {
 
@@ -209,7 +209,7 @@ private USBDevice createDevice(String devicePath, MemorySegment hubHandle, int u
             var configDesc = getDescriptor(hubHandle, usbPortNum, CONFIGURATION_DESCRIPTOR_TYPE, 0, (short) 0, arena);
 
             // create new device
-            var device = new WindowsUSBDevice(devicePath, vendorId, productId, configDesc);
+            var device = new WindowsUSBDevice(devicePath, vendorId, productId, configDesc, isComposite);
             device.setFromDeviceDescriptor(descriptorSegment);
             device.setProductString(descriptorSegment, index -> getStringDescriptor(hubHandle, usbPortNum, index));