From: Daniel Berger <djberge@...>
Date: 2002-12-10T06:10:47+09:00
Subject: Re: Ruby base64 encoding/decoding

Emiel van de Laar wrote:

> * Michael Neumann (520079130762-0001@t-online.de) wrote:
> > On Mon, 2002-12-09 at 21:22, Emiel van de Laar wrote:
> > > Fellow Ruby users,
> > >
> > > I'm looking for a Ruby module that handles base64 encoding/decoding. RAA
> > > doesn't seem to carry one. Perhaps it doesn't exist and someone with
> > > some spare time could port the PERL version. :)  In my opinion this is
> > > a fundamental module the Ruby community is missing at the moment.
> >
> > See String#unpack and Array#pack.
> >
> > s = [binaryString].pack("m")   # encodes binaryString as base64
> > s.unpack("m")                  # decodes s
>
> Wow it comes standard with Ruby. Nice. Thanks for pointing me in the
> right direction. ;)
>
> Emiel
> --
> E F van de Laar
> Beheers Commissaris dispuut Interlink
> +31648183479
> www.il.fontys.nl/~emiel

There is a base64 module, btw, that comes as part of the standard distro, so
you can do: require "base64".

4 methods available:
decode
decode64
encode
encode64

The full code is below.

These methods should be wrapped in their own module, IMHO, to avoid name
collision.

Regards,

Dan

# base64.rb from 1.6.7
require "kconv"

def decode64(str)
  str.unpack("m")[0]
end

def decode_b(str)
  str.gsub!(/=\?ISO-2022-JP\?B\?([!->@-~]+)\?=/i) {
    decode64($1)
  }
  str = Kconv::toeuc(str)
  str.gsub!(/=\?SHIFT_JIS\?B\?([!->@-~]+)\?=/i) {
    decode64($1)
  }
  str = Kconv::toeuc(str)
  str.gsub!(/\n/, ' ')
  str.gsub!(/\0/, '')
  str
end

def encode64(bin)
  [bin].pack("m")
end

def b64encode(bin, len = 60)
  encode64(bin).scan(/.{1,#{len}}/o) do
    print $&, "\n"
  end
end