Gran Turismo File System (GTFS): Ruby parsing library

File extension

vol

KS implementation details

License: CC0-1.0

References

This page hosts a formal specification of Gran Turismo File System (GTFS) 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 = GranTurismoVol.from_file("path/to/local/file.vol")

Or parse structure from a string of bytes:

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

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

data.magic # => get magic

Ruby source code to parse Gran Turismo File System (GTFS)

gran_turismo_vol.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

class GranTurismoVol < Kaitai::Struct::Struct
  def initialize(_io, _parent = nil, _root = self)
    super(_io, _parent, _root)
    _read
  end

  def _read
    @magic = @_io.read_bytes(8)
    raise Kaitai::Struct::ValidationNotEqualError.new([71, 84, 70, 83, 0, 0, 0, 0].pack('C*'), magic, _io, "/seq/0") if not magic == [71, 84, 70, 83, 0, 0, 0, 0].pack('C*')
    @num_files = @_io.read_u2le
    @num_entries = @_io.read_u2le
    @reserved = @_io.read_bytes(4)
    raise Kaitai::Struct::ValidationNotEqualError.new([0, 0, 0, 0].pack('C*'), reserved, _io, "/seq/3") if not reserved == [0, 0, 0, 0].pack('C*')
    @offsets = Array.new(num_files)
    (num_files).times { |i|
      @offsets[i] = @_io.read_u4le
    }
    self
  end
  class FileInfo < Kaitai::Struct::Struct
    def initialize(_io, _parent = nil, _root = self)
      super(_io, _parent, _root)
      _read
    end

    def _read
      @timestamp = @_io.read_u4le
      @offset_idx = @_io.read_u2le
      @flags = @_io.read_u1
      @name = (Kaitai::Struct::Stream::bytes_terminate(Kaitai::Struct::Stream::bytes_strip_right(@_io.read_bytes(25), 0), 0, false)).force_encoding("ASCII")
      self
    end
    def size
      return @size unless @size.nil?
      @size = ((_root.offsets[(offset_idx + 1)] & 4294965248) - _root.offsets[offset_idx])
      @size
    end
    def body
      return @body unless @body.nil?
      if !(is_dir)
        _pos = @_io.pos
        @_io.seek((_root.offsets[offset_idx] & 4294965248))
        @body = @_io.read_bytes(size)
        @_io.seek(_pos)
      end
      @body
    end
    def is_dir
      return @is_dir unless @is_dir.nil?
      @is_dir = (flags & 1) != 0
      @is_dir
    end
    def is_last_entry
      return @is_last_entry unless @is_last_entry.nil?
      @is_last_entry = (flags & 128) != 0
      @is_last_entry
    end
    attr_reader :timestamp
    attr_reader :offset_idx
    attr_reader :flags
    attr_reader :name
  end
  def ofs_dir
    return @ofs_dir unless @ofs_dir.nil?
    @ofs_dir = offsets[1]
    @ofs_dir
  end
  def files
    return @files unless @files.nil?
    _pos = @_io.pos
    @_io.seek((ofs_dir & 4294965248))
    @files = Array.new(_root.num_entries)
    (_root.num_entries).times { |i|
      @files[i] = FileInfo.new(@_io, self, @_root)
    }
    @_io.seek(_pos)
    @files
  end
  attr_reader :magic
  attr_reader :num_files
  attr_reader :num_entries
  attr_reader :reserved
  attr_reader :offsets
end