Windows: UsbDk: Implement get_config_descriptor_by_value()

This fixes a NULL pointer dereference when the user selects the UsbDk
backend and subsequently calls libusb_get_config_descriptor_by_value().

Closes #395

Signed-off-by: Chris Dickens <christopher.a.dickens@gmail.com>

diff --git a/libusb/os/windows_usbdk.c b/libusb/os/windows_usbdk.c
index 6b16675..1355000 100644 (file)
--- a/libusb/os/windows_usbdk.c
+++ b/libusb/os/windows_usbdk.c
@@ -370,7 +370,25 @@ static int usbdk_get_config_descriptor(struct libusb_device *dev, uint8_t config
        return (int)size;
 }
 
-static inline int usbdk_get_active_config_descriptor(struct libusb_device *dev, unsigned char *buffer, size_t len)
+static int usbdk_get_config_descriptor_by_value(struct libusb_device *dev, uint8_t bConfigurationValue,
+       unsigned char **buffer)
+{
+       struct usbdk_device_priv *priv = _usbdk_device_priv(dev);
+       PUSB_CONFIGURATION_DESCRIPTOR config_header;
+       uint8_t index;
+
+       for (index = 0; index < dev->num_configurations; index++) {
+               config_header = priv->config_descriptors[index];
+               if (config_header->bConfigurationValue == bConfigurationValue) {
+                       *buffer = (unsigned char *)priv->config_descriptors[index];
+                       return (int)config_header->wTotalLength;
+               }
+       }
+
+       return LIBUSB_ERROR_NOT_FOUND;
+}
+
+static int usbdk_get_active_config_descriptor(struct libusb_device *dev, unsigned char *buffer, size_t len)
 {
        return usbdk_get_config_descriptor(dev, _usbdk_device_priv(dev)->active_configuration,
                        buffer, len);
@@ -794,7 +812,7 @@ const struct windows_backend usbdk_backend = {
        usbdk_get_device_descriptor,
        usbdk_get_active_config_descriptor,
        usbdk_get_config_descriptor,
-       NULL,//usbdk_get_config_descriptor_by_value,
+       usbdk_get_config_descriptor_by_value,
        usbdk_get_configuration,
        usbdk_set_configuration,
        usbdk_claim_interface,

diff --git a/libusb/version_nano.h b/libusb/version_nano.h
index 5d22c03..1617e40 100644 (file)
--- a/libusb/version_nano.h
+++ b/libusb/version_nano.h
@@ -1 +1 @@
-#define LIBUSB_NANO 11300
+#define LIBUSB_NANO 11301