static int ComputeMetadataBoundsFromSuperClass(SwiftNominalTypeDescriptor descHandle)
{
// the computed size of a class metadata is the size of its members + the size of its super class.
// If there is no super class, the size of the basic class metadata
int bounds = 0;
var superPtr = descHandle.ResilientSuperclass;
if (superPtr != IntPtr.Zero)
{
bounds = ComputeMetadataBoundsFromSuperClass(new SwiftNominalTypeDescriptor(superPtr));
}
else
{
bounds = SwiftMetatype.ClassSizeWithoutMembers;
}
if (descHandle.ImmediateMembersAreNegative())
{
bounds -= descHandle.MetadataNegativeSizeInWords;
}
else
{
bounds += descHandle.MetadataPositiveSizeInWords;
}
return(bounds);
}
internal static IntPtr DescriptorHandleForType(Type interfaceType)
{
// internal version, no exceptions
var typeAttribute = interfaceType.GetCustomAttribute <SwiftProtocolTypeAttribute> ();
if (typeAttribute == null)
{
return(IntPtr.Zero);
}
var desc = SwiftNominalTypeDescriptor.FromDylibFile(typeAttribute.LibraryName, DLOpenMode.Now, typeAttribute.ProtocolDescriptor);
if (!desc.HasValue)
{
return(IntPtr.Zero);
}
return(desc.Value.Handle);
}
public static SwiftNominalTypeDescriptor DescriptorForType(Type interfaceType)
{
Exceptions.ThrowOnNull(interfaceType, nameof(interfaceType));
if (!interfaceType.IsInterface)
{
throw new SwiftRuntimeException($"Type {interfaceType.Name} is not an interface.");
}
var typeAttribute = interfaceType.GetCustomAttribute <SwiftProtocolTypeAttribute> ();
if (typeAttribute == null)
{
throw new SwiftRuntimeException($"Type {interfaceType.Name} does not have a SwiftProtocolType attribute");
}
var desc = SwiftNominalTypeDescriptor.FromDylibFile(typeAttribute.LibraryName, DLOpenMode.Now, typeAttribute.ProtocolDescriptor);
if (!desc.HasValue)
{
throw new SwiftRuntimeException($"Unable to find swift protocol type descriptor for {interfaceType.Name} with symbol {typeAttribute.ProtocolDescriptor} in file {typeAttribute.LibraryName}");
}
return(desc.Value);
}
