XR NPU counter to pcap

xr2pcap.rb

#!/usr/bin/env ruby

# put output of 'monitor np counter PUNT_IPV4_ADJ_NULL_RTE_EXCD np3 count 25 location 0/1/CPU0' to a file 'foox.txt'
# run './xr2pcap.rb foox.txt' and you'll have 'packets.txt' and 'packets.pcap'

class XRNPUCounter
  PACKET_START = /byte packet/
  LINE_RE      = /^....: (.{48}).*/

  def self.parse lines
    c = new
    packets = c.parse_lines lines
    c.parse_packets packets
  end

  def parse_lines lines
    packet   = false
    count    = -1
    packets  = []
    lines.each do |line|
      next if not packet and not line.match PACKET_START
      if line.match PACKET_START
        packet = true
        count += 1
        packets[count] = ''
        next
      end
      packets[count] += line
      packet = false if not line.match(/^\d/)
    end
    packets
  end

  def parse_packets packets
    parsed = []
    packets.each_with_index do |packet, index|
      hex = []
      packet.lines.each do |line|
        line = line.sub LINE_RE, '\1'
        hex << line.split
      end
      parsed.push "0000000 " + hex.flatten.join(" ")
    end
    parsed
  end
end


if $0 == __FILE__
  begin
    packets = XRNPUCounter.parse ARGF
    File.write "packets.txt", packets.join("\n")
    %x(text2pcap packets.txt packets.pcap)
  rescue => error
    warn error.class.to_s + ": " + error.message
    raise if $DEBUG
  end
end