class FFI::VariadicInvoker

def attach(mod, mname)
  invoker = self
  params = "*args"
  call = "call"
  mname = mname.to_sym
  mod.module_eval <<-code, __FILE__, __LINE__
    @ffi_functions = {} unless defined?(@ffi_functions)
    @ffi_functions[#{mname.inspect}] = invoker
    def self.#{mname}(#{params})
      @ffi_functions[#{mname.inspect}].#{call}(#{params})
    end
    define_method(#{mname.inspect}, &method(#{mname.inspect}))
  code
  invoker
end

def call(*args, &block)
  param_types = Array.new(@fixed)
  param_values = Array.new
  @fixed.each_with_index do |t, i|
    param_values << args[i]
  end
  i = @fixed.length
  while i < args.length
    param_types << FFI.find_type(args[i], @type_map)
    param_values << args[i + 1]
    i += 2
  end
  invoke(param_types, param_values, &block)
end

def param_types
  [*@fixed, Type::Builtin::VARARGS]
end