Class: PacketGen::PcapNG::Block Abstract

Inherits:
Types::Fields show all
Defined in:
lib/packetgen/pcapng/block.rb

Overview

This class is abstract.

Base class for all block types

Author:

  • Sylvain Daubert

Direct Known Subclasses

EPB, IDB, SHB, SPB, UnknownBlock

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods inherited from Types::Fields

#[], #[]=, #body=, define_bit_fields_on, define_field, define_field_after, define_field_before, #fields, #force_binary, inherited, #inspect, #read, #sz, #to_h, #to_s

Constructor Details

#initialize(options = {}) ⇒ Block

Returns a new instance of Block.



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# File 'lib/packetgen/pcapng/block.rb', line 29

def initialize(options={})
  super
end

Instance Attribute Details

#block_len ⇒ Integer

32-bit block length

Returns:

  • (Integer) 


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# File 'lib/packetgen/pcapng/block.rb', line 23

define_field :block_len, Types::Int32

#endian ⇒ :little, :big

Returns:

  • (:little, :big) 


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# File 'lib/packetgen/pcapng/block.rb', line 14

def endian
  @endian
end

#type ⇒ Integer

32-bit block type

Returns:

  • (Integer) 


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# File 'lib/packetgen/pcapng/block.rb', line 19

define_field :type, Types::Int32

Instance Method Details

#has_options? ⇒ Boolean

Has this block option?

Returns:

  • (Boolean) 


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# File 'lib/packetgen/pcapng/block.rb', line 35

def has_options?
  @fields.has_key?(:options) && @fields[:options].sz > 0
end

#pad_field(*fields) ⇒ void

This method returns an undefined value.

Pad given field to 32 bit boundary, if needed

Parameters:

  • fields (Array<Symbol>) —

    block fields to pad



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# File 'lib/packetgen/pcapng/block.rb', line 49

def pad_field(*fields)
  fields.each do |field|
    unless @fields[field].size % 4 == 0
      @fields[field] << "\x00" * (4 - (@fields[field].size % 4))
    end
  end
end

#recalc_block_len ⇒ void

This method returns an undefined value.

Calculate block length and update :block_len and block_len2 fields



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# File 'lib/packetgen/pcapng/block.rb', line 41

def recalc_block_len
  len = fields.map { |f| @fields[f].to_s }.join.size
  self.block_len = self.block_len2 = len
end