Openflow parser

lib/openflow/multipart/meter/reply.ex

@@ -0,0 +1,63 @@
+defmodule Openflow.Multipart.Meter.Reply do
+  defstruct(
+    version:      4,
+    xid:          0,
+    datapath_id:  nil, # virtual field
+    flags:        [],
+    meters:       []
+  )
+
+  alias __MODULE__
+
+  def ofp_type, do: 18
+
+  def read(<<meters_bin::bytes>>) do
+    meters = Openflow.Multipart.Meter.read(meters_bin)
+    %Reply{meters: meters}
+  end
+end
+
+defmodule Openflow.Multipart.Meter do
+  defstruct(
+    meter_id:        0,
+    flow_count:      0,
+    packet_in_count: 0,
+    byte_in_count:   0,
+    duration_sec:    0,
+    duration_nsec:   0,
+    band_stats:     []
+  )
+
+  @ofp_meter_stats_size 40
+
+  alias __MODULE__
+
+  def read(binary) do
+    do_read([], binary)
+  end
+
+  # private functions
+
+  defp do_read(acc, ""), do: Enum.reverse(acc)
+  defp do_read(acc, <<_::32, length::16, _binary::bytes>> = binary) do
+    <<meter_bin::size(length)-bytes, rest::bytes>> = binary
+    do_read([codec(meter_bin)|acc], rest)
+  end
+
+  defp codec(<<meter_id::32, length::16, _::size(6)-unit(8),
+               flow_count::32, packet_in_count::64, byte_in_count::64,
+               duration_sec::32, duration_nsec::32, tail::bytes>>) do
+    band_stats_size = length - @ofp_meter_stats_size
+    <<band_stats_bin::size(band_stats_size)-bytes, _rest::bytes>> = tail
+    band_stats = for <<packet_band_count::64, byte_band_count::64 <- band_stats_bin>> do
+      %{packet_band_count: packet_band_count,byte_band_count: byte_band_count}
+    end
+    %Meter{meter_id: meter_id,
+           flow_count: flow_count,
+           packet_in_count: packet_in_count,
+           byte_in_count: byte_in_count,
+           duration_sec: duration_sec,
+           duration_nsec: duration_nsec,
+           band_stats: band_stats}
+  end
+end

lib/openflow/multipart/meter/request.ex

@@ -0,0 +1,29 @@
+defmodule Openflow.Multipart.Meter.Request do
+  defstruct(
+    version:      4,
+    xid:          0,
+    datapath_id:  nil, # virtual field
+    flags: [],
+    meter_id:    :all
+  )
+
+  alias __MODULE__
+
+  def ofp_type, do: 18
+
+  def new(meter_id \\ :all) do
+    %Request{meter_id: meter_id}
+  end
+
+  def read(<<meter_id_int::32, _::size(4)-unit(8)>>) do
+    meter_id = Openflow.Utils.get_enum(meter_id_int, :meter_id)
+    %Request{meter_id: meter_id}
+  end
+
+  def to_binary(%Request{meter_id: meter_id} = msg) do
+    meter_id_int = Openflow.Utils.get_enum(meter_id, :meter_id)
+    body_bin = <<meter_id_int::32, 0::size(4)-unit(8)>>
+    header_bin = Openflow.Multipart.Request.header(msg)
+    <<header_bin::bytes, body_bin::bytes>>
+  end
+end