tres/lib/openflow/instruction.ex
2019-05-05 23:39:46 +09:00

44 lines
1.4 KiB
Elixir

defmodule Openflow.Instruction do
@moduledoc """
Openflow instruction codec handler
"""
@type instruction ::
Openflow.Instruction.ApplyActions.t()
| Openflow.Instruction.WriteActions.t()
| Openflow.Instruction.ClearActions.t()
| Openflow.Instruction.GotoTable.t()
| Openflow.Instruction.WriteMetadata.t()
| Openflow.Instruction.Meter.t()
@spec read(<<_::32, _::_*8>>) :: [instruction()]
def read(instruction_bin),
do: do_read([], instruction_bin)
@spec to_binary(instruction()) :: <<_::32, _::_*8>>
def to_binary(instructions) when is_list(instructions),
do: to_binary(<<>>, instructions)
@spec to_binary([instruction()]) :: <<_::32, _::_*8>>
def to_binary(instruction),
do: to_binary([instruction])
# private functions
@spec do_read([instruction()], <<_::_*8>>) :: [instruction()]
defp do_read(acc, <<>>), do: Enum.reverse(acc)
defp do_read(acc, <<type::16, length::16, _::bytes>> = binary) do
<<instruction_bin::size(length)-bytes, rest::bytes>> = binary
codec = Openflow.Enums.to_atom(type, :instruction_type)
do_read([codec.read(instruction_bin) | acc], rest)
end
@spec to_binary(<<_::_*8>>) :: [instruction()]
defp to_binary(acc, []), do: acc
defp to_binary(acc, [instruction | rest]) do
codec = instruction.__struct__
to_binary(<<acc::bytes, codec.to_binary(instruction)::bytes>>, rest)
end
end