lib/zip/extra_field.rb
module Zip
class ExtraField < Hash
ID_MAP = {}
def initialize(binstr = nil)
binstr and merge(binstr)
end
def extra_field_type_exist(binstr, id, len, i)
field_name = ID_MAP[id].name
if self.member?(field_name)
self[field_name].merge(binstr[i, len + 4])
else
field_obj = ID_MAP[id].new(binstr[i, len + 4])
self[field_name] = field_obj
end
end
def extra_field_type_unknown(binstr, len, i)
create_unknown_item unless self['Unknown']
if !len || len + 4 > binstr[i..-1].bytesize
self['Unknown'] << binstr[i..-1]
return
end
self['Unknown'] << binstr[i, len + 4]
end
def create_unknown_item
s = ''
class << s
alias_method :to_c_dir_bin, :to_s
alias_method :to_local_bin, :to_s
end
self['Unknown'] = s
end
def merge(binstr)
return if binstr.empty?
i = 0
while i < binstr.bytesize
id = binstr[i, 2]
len = binstr[i + 2, 2].to_s.unpack('v').first
if id && ID_MAP.member?(id)
extra_field_type_exist(binstr, id, len, i)
elsif id
create_unknown_item unless self['Unknown']
break unless extra_field_type_unknown(binstr, len, i)
end
i += len + 4
end
end
def create(name)
unless field_class = ID_MAP.values.find { |k| k.name == name }
raise Error, "Unknown extra field '#{name}'"
end
self[name] = field_class.new
end
# place Unknown last, so "extra" data that is missing the proper signature/size
# does not prevent known fields from being read back in
def ordered_values
result = []
self.each { |k,v| k == 'Unknown' ? result.push(v) : result.unshift(v) }
result
end
def to_local_bin
ordered_values.map! { |v| v.to_local_bin.force_encoding('BINARY') }.join
end
alias :to_s :to_local_bin
def to_c_dir_bin
ordered_values.map! { |v| v.to_c_dir_bin.force_encoding('BINARY') }.join
end
def c_dir_size
to_c_dir_bin.bytesize
end
def local_size
to_local_bin.bytesize
end
alias :length :local_size
alias :size :local_size
end
end
require 'zip/extra_field/generic'
require 'zip/extra_field/universal_time'
require 'zip/extra_field/old_unix'
require 'zip/extra_field/unix'
require 'zip/extra_field/zip64'
require 'zip/extra_field/zip64_placeholder'
require 'zip/extra_field/aes'
# Copyright (C) 2002, 2003 Thomas Sondergaard
# rubyzip is free software; you can redistribute it and/or
# modify it under the terms of the ruby license.