Openflow parser

lib/openflow/multipart/flow/reply.ex

@@ -0,0 +1,75 @@
+defmodule Openflow.Multipart.Flow.Reply do
+  defstruct(
+    version:      4,
+    xid:          0,
+    datapath_id:  nil, # virtual field
+    flags:        [],
+    flows:        []
+  )
+
+  alias __MODULE__
+
+  def ofp_type, do: 18
+
+  def new(flows \\ []) do
+    %Reply{flows: flows}
+  end
+
+  def read(<<flows_bin::bytes>>) do
+    flows = Openflow.Multipart.FlowStats.read(flows_bin)
+    %Reply{flows: flows}
+  end
+end
+
+defmodule Openflow.Multipart.FlowStats do
+  defstruct(
+    table_id:      0,
+    duration_sec:  0,
+    duration_nsec: 0,
+    priority:      0,
+    idle_timeout:  0,
+    hard_timeout:  0,
+    flags:         0,
+    cookie:        0,
+    packet_count:  0,
+    byte_count:    0,
+    match:        [],
+    instructions: []
+  )
+
+  alias __MODULE__
+
+  def read(binary) do
+    do_read([], binary)
+  end
+
+  # private functions
+
+  defp do_read(acc, ""), do: Enum.reverse(acc)
+  defp do_read(acc, <<length::16, _tail::bytes>> = binary) do
+    <<flow_stats_bin::size(length)-bytes, rest::bytes>> = binary
+    do_read([codec(flow_stats_bin)|acc], rest)
+  end
+
+  defp codec(<<_length::16, table_id_int::8, 0::8, duration_sec::32,
+               duration_nsec::32, priority::16, idle::16, hard::16,
+               flags_int::16, _::size(4)-unit(8), cookie::64,
+               packet_count::64, byte_count::64, tail::bytes>>) do
+    {match, instructions_bin} = Openflow.Match.read(tail)
+    table_id = Openflow.Utils.get_enum(table_id_int, :table_id)
+    flags = Openflow.Enums.int_to_flags(flags_int, :flow_mod_flags)
+    instructions = Openflow.Instruction.read(instructions_bin)
+    %FlowStats{table_id: table_id,
+               duration_sec: duration_sec,
+               duration_nsec: duration_nsec,
+               priority: priority,
+               idle_timeout: idle,
+               hard_timeout: hard,
+               flags: flags,
+               cookie: cookie,
+               packet_count: packet_count,
+               byte_count: byte_count,
+               match: match,
+               instructions: instructions}
+  end
+end