Byte array with an `_io` member: Ruby parsing library

Helper type to work around Kaitai Struct not providing an _io member for plain byte arrays.

KS implementation details

License: MIT

This page hosts a formal specification of Byte array with an `_io` member using Kaitai Struct. This specification can be automatically translated into a variety of programming languages to get a parsing library.

Usage

Runtime library

All parsing code for Ruby generated by Kaitai Struct depends on the Ruby runtime library. You have to install it before you can parse data.

The Ruby runtime library can be installed from RubyGems:

gem install kaitai-struct

Code

Parse a local file and get structure in memory:

data = BytesWithIo.from_file("path/to/local/file.bin")

Or parse structure from a string of bytes:

bytes = "\x00\x01\x02..."
data = BytesWithIo.new(Kaitai::Struct::Stream.new(bytes))

After that, one can get various attributes from the structure by invoking getter methods like:

data.data # => The actual data.

Ruby source code to parse Byte array with an `_io` member

bytes_with_io.rb

# This is a generated file! Please edit source .ksy file and use kaitai-struct-compiler to rebuild

require 'kaitai/struct/struct'

unless Gem::Version.new(Kaitai::Struct::VERSION) >= Gem::Version.new('0.9')
  raise "Incompatible Kaitai Struct Ruby API: 0.9 or later is required, but you have #{Kaitai::Struct::VERSION}"
end


##
# Helper type to work around Kaitai Struct not providing an `_io` member for plain byte arrays.
class BytesWithIo < Kaitai::Struct::Struct
  def initialize(_io, _parent = nil, _root = self)
    super(_io, _parent, _root)
    _read
  end

  def _read
    @data = @_io.read_bytes_full
    self
  end

  ##
  # The actual data.
  attr_reader :data
end