public static ConfigurationDescriptor Parse(byte[] srcData)
{
ConfigurationDescriptor c = new ConfigurationDescriptor();
if (srcData.Length < 9 || srcData[0] != 9 || srcData[1] != (byte)DescriptorType.Configuration)
{
throw new Exception("Invalid configuration descriptor");
}
int fullLength = srcData[2] | (srcData[3] << 8);
if (fullLength < 9 || fullLength > srcData.Length)
{
throw new Exception("Invalid configuration descriptor length");
}
c.NumInterfaces = srcData[4];
c.Index = srcData[5];
c.DescriptionString = srcData[6];
c.Attributes = (DeviceConfigurationFlags)srcData[7];
c.PowerDraw = srcData[8];
int cursor = 9;
while (cursor < fullLength)
{
c.RawDescriptors.Add(new DescriptorNode(srcData, ref cursor));
}
if (cursor != fullLength)
{
throw new Exception("Configuration descriptors overran specified length");
}
// Next step, parse them off into interfaces.
List <DescriptorNode> nodes = new List <DescriptorNode>();
DescriptorNode nodeInterface = null;
foreach (DescriptorNode n in c.RawDescriptors)
{
if (n.Type == DescriptorType.Interface)
{
if (nodeInterface != null)
{
c.Interfaces.Add(InterfaceDescriptor.Parse(nodeInterface, nodes));
}
nodes.Clear();
nodeInterface = n;
}
else
{
if (nodeInterface == null)
{
throw new Exception("Configuration descriptor has unknown descriptor blocks before the first interface.");
}
nodes.Add(n);
}
}
if (nodeInterface != null)
{
c.Interfaces.Add(InterfaceDescriptor.Parse(nodeInterface, nodes));
}
return(c);
}
public ConfigurationDescriptor GetConfigurationDescriptor()
{
// Todo: more than just the first configuration.
return(ConfigurationDescriptor.Parse(GetDescriptor(DescriptorType.Configuration, 0)));
}
