wrap_arg

# File ext/dl/lib/dl/value.rb, line 48
    def wrap_arg(arg, ty, funcs = [], &block)
        require 'dl/func'

        funcs ||= []
        case arg
        when nil
          return 0
        when CPtr
          return arg.to_i
        when IO
          case ty
          when TYPE_VOIDP
            return CPtr[arg].to_i
          else
            return arg.to_i
          end
        when Function
          if( block )
            arg.bind_at_call(&block)
            funcs.push(arg)
          elsif !arg.bound?
            raise(RuntimeError, "block must be given.")
          end
          return arg.to_i
        when String
          if( ty.is_a?(Array) )
            return arg.unpack('C*')
          else
            case SIZEOF_VOIDP
            when SIZEOF_LONG
              return [arg].pack("p").unpack("l!")[0]
            when SIZEOF_LONG_LONG
              return [arg].pack("p").unpack("q")[0]
            else
              raise(RuntimeError, "sizeof(void*)?")
            end
          end
        when Float, Integer
          return arg
        when Array
          if( ty.is_a?(Array) ) # used only by struct
            case ty[0]
            when TYPE_VOIDP
              return arg.collect{|v| Integer(v)}
            when TYPE_CHAR
              if( arg.is_a?(String) )
                return val.unpack('C*')
              end
            end
            return arg
          else
            return arg
          end
        else
          if( arg.respond_to?(:to_ptr) )
            return arg.to_ptr.to_i
          else
            begin
              return Integer(arg)
            rescue
              raise(ArgumentError, "unknown argument type: #{arg.class}")
            end
          end
        end
    end