module Rfc2047

$Id: rfc2047.rb,v 1.4 2003/04/18 20:55:56 sam Exp $ MODIFIED slightly by William Morgan

An implementation of RFC 2047 decoding.

This module depends on the iconv library by Nobuyoshi Nakada, which I've heard may be distributed as a standard part of Ruby 1.8. Many thanks to him for helping with building and using iconv.

Thanks to “Josef 'Jupp' Schugt” <jupp / gmx.de> for pointing out an error with stateful character sets.

Copyright © Sam Roberts <sroberts / uniserve.com> 2004

This file is distributed under the same terms as Ruby.

Constants

WORDSEQ

Public Class Methods

decode_to(target, from) click to toggle source

Decodes a string, from, containing RFC 2047 encoded words into a target character set, target. See iconv_open(3) for information on the supported target encodings. If one of the encoded words cannot be converted to the target encoding, it is left in its encoded form.

# File lib/sup/rfc2047.rb, line 29
def Rfc2047.decode_to(target, from)
  from = from.gsub(WORDSEQ, '\1')
  out = from.gsub(WORD) do
    |word|
    charset, encoding, text = $1, $2, $3

    # B64 or QP decode, as necessary:
    case encoding
      when 'b', 'B'
        #puts text
        text = text.unpack('m*')[0]
        #puts text.dump

      when 'q', 'Q'
        # RFC 2047 has a variant of quoted printable where a ' ' character
        # can be represented as an '_', rather than =32, so convert
        # any of these that we find before doing the QP decoding.
        text = text.tr("_", " ")
        text = text.unpack('M*')[0]

      # Don't need an else, because no other values can be matched in a
      # WORD.
    end

    text.transcode(target, charset)
  end
end
is_encoded?(s;) click to toggle source
# File lib/sup/rfc2047.rb, line 23
def Rfc2047.is_encoded? s; s =~ WORD end