Message/MIME/Charset.pm


=head1 NAME

Message::MIME::Charset Perl module

=head1 DESCRIPTION

Perl module for MIME charset.

=cut

## NOTE: You should not require/use other module (even it
##       is part of Message::* Perl Modules) as far as possible,
##       to be able to use this module (M::M::Charset) from
##       other (non-Message::*) modules.

package Message::MIME::Charset;
use strict;
use vars qw(%CHARSET %MSNAME2IANANAME %REG $VERSION);
$VERSION=do{my @r=(q$Revision: 1.12 $=~/\d+/g);sprintf "%d."."%02d" x $#r,@r};

&_builtin_charset;
sub _builtin_charset () {

$CHARSET{'*DEFAULT'} = {
        preferred_name  => '',
        
        encoder => sub { $_[1] },
        decoder => sub { $_[1] },
        
        mime_text       => 1,   ## Suitability in use as MIME text/* charset
        #accept_cte     => [qw/7bit .../],
        cte_7bit_preferred      => 'quoted-printable',
};
$CHARSET{'*default'} = $CHARSET{'*DEFAULT'};

$CHARSET{'us-ascii'} = {
        preferred_name  => 'us-ascii',
        
        encoder => sub { $_[1] },
        decoder => sub { $_[1] },
        
        mime_text       => 1,
        cte_7bit_preferred      => 'quoted-printable',
};

$CHARSET{'iso-2022-int-1'} = {
        preferred_name  => 'iso-2022-int-1',
        
        encoder => sub { $_[1] },
        decoder => sub { $_[1] },
        
        mime_text       => 1,
};

$CHARSET{'unknown-8bit'} = {
        preferred_name  => 'unknown-8bit',
        
        encoder => sub { $_[1] },
        decoder => sub { $_[1] },
        
        mime_text       => 1,
        cte_7bit_preferred      => 'base64',
};

$CHARSET{'x-unknown'} = {
        preferred_name  => 'x-unknown',
        
        encoder => sub { $_[1] },
        decoder => sub { $_[1] },
        
        mime_text       => 0,
        cte_7bit_preferred      => 'base64',
};

$CHARSET{'*undef'} = {
        preferred_name  => '',
        
        #encoder        => sub { $_[1] },
        #decoder        => sub { $_[1] },
        
        mime_text       => 0,
        cte_7bit_preferred      => 'base64',
};

}       # /builtin_charset

my %_MINIMUMIZER = (
        'euc-jp'        => \&_name_euc_japan,
        'euc-jisx0213'  => \&_name_euc_japan,
        'euc-jisx0213-plane1'   => \&_name_euc_japan,
        'x-euc-jisx0213-packed' => \&_name_euc_japan,
        'x-iso-2022'    => \&_name_8bit_iso2022,
        'iso-2022-cn'   => \&_name_8bit_iso2022,
        'iso-2022-cn-ext'       => \&_name_8bit_iso2022,
        'iso-2022-int-1'        => \&_name_net_ascii_8bit,
        'iso-2022-jp'   => \&_name_8bit_iso2022,
        'iso-2022-jp-1' => \&_name_8bit_iso2022,
        'iso-2022-jp-2' => \&_name_8bit_iso2022,
        'iso-2022-jp-3' => \&_name_8bit_iso2022,
        'iso-2022-jp-3-plane1'  => \&_name_8bit_iso2022,
        'iso-2022-kr'   => \&_name_8bit_iso2022,
        'iso-8859-1'    => \&_name_8bit_iso2022,
        'iso-10646-j-1' => \&_name_utf16be,
        'iso-10646-ucs-2'       => \&_name_utf16be,
        'iso-10646-ucs-4'       => \&_name_utf32be,
        'iso-10646-ucs-basic'   => \&_name_utf16be,
        'iso-10646-unicode-latin1'      => \&_name_utf16be,
        jis_x0201       => \&_name_shift_jis,
        junet   => \&_name_8bit_iso2022,
        'x-junet8'      => \&_name_net_ascii_8bit,
        shift_jis       => \&_name_shift_jis,
        shift_jisx0213  => \&_name_shift_jis,
        'shift_jisx0213-plane1' => \&_name_shift_jis,
        'x-sjis'        => \&_name_shift_jis,
        'us-ascii'      => \&_name_net_ascii_8bit,
        'utf-8' => \&_name_net_ascii_8bit,
        'utf-16be'      => \&_name_utf16be,
        'utf-32be'      => \&_name_utf32be,
);

%MSNAME2IANANAME = (
        'iso-2022-jp'   => 'x-iso2022jp-cp932',
        'ks_c_5601-1987'        => 'windows-949',
);

sub make_charset ($%) {
  my $name = shift;
  return unless $name;  ## Note: charset "0" is not supported.
  my %definition = @_;
  
  $definition{preferred_name} ||= $name;
  if ($definition{preferred_name} ne $name
      && ref $CHARSET{$definition{preferred_name}}) {
  ## New charset is an alias of defined charset,
    $CHARSET{$name} = $CHARSET{$definition{preferred_name}};
    return;
  } elsif ($definition{alias_of} && ref $CHARSET{$definition{alias_of}}) {
  ## New charset is an alias of defined charset,
    $CHARSET{$name} = $CHARSET{$definition{alias_of}};
    return;
  }
  $CHARSET{$name} = \%definition;
  
  ## Set default values
  #$definition{encoder} ||= sub { $_[1] };
  #$definition{decoder} ||= sub { $_[1] };

  $definition{mime_text} = 0 unless defined $definition{mime_text};
  $definition{cte_7bit_preferred} = 'base64'
    unless defined $definition{cte_7bit_preferred};
}

sub encode ($$) {
  my ($charset, $s) = (lc shift, shift);
  my $c = ref $CHARSET{$charset}->{encoder}? $charset: '*undef';
  if (ref $CHARSET{$c}->{encoder}) {
    my ($t, %r) = &{$CHARSET{$c}->{encoder}} ($charset, $s);
    unless (defined $r{success}) {
      $r{success} = 1;
    }
    return ($t, %r);
  }
  ($s, success => 0);
}

sub decode ($$) {
  my ($charset, $s) = (lc shift, shift);
  my $c = ref $CHARSET{$charset}->{decoder}? $charset: '*undef';
  if (ref $CHARSET{$c}->{decoder}) {
    my ($t, %r) = &{$CHARSET{$c}->{decoder}} ($charset, $s);
    unless (defined $r{success}) {
      $r{success} = 1;
    }
    return ($t, %r);
  }
  ($s, success => 0);
}

sub name_normalize ($) {
  my $name = lc shift;
  $CHARSET{$name}->{preferred_name} || $name;
}

sub name_minimumize ($$) {
  my ($charset, $s) = (lc shift, shift);
  if (ref $CHARSET{$charset}->{name_minimumizer} eq 'CODE') {
    return &{$CHARSET{$charset}->{name_minimumizer}} ($charset, $s);
  } elsif (ref $_MINIMUMIZER{$charset}) {
    return &{$_MINIMUMIZER{$charset}} ($charset, $s);
  } elsif (ref $CHARSET{'*undef'}->{name_minimumizer} eq 'CODE') {
    return &{$CHARSET{'*undef'}->{name_minimumizer}} ($charset, $s);
  }
  (charset => $charset);
}

sub msname2iananame ($) {
  my $mscharset = shift;
  $MSNAME2IANANAME{$mscharset} || $mscharset;
}

sub _name_7bit_iso2022 ($$) {shift;
  my $s = shift;
  if ($s =~ /[\x0E\x0F\x1B]/) {
    return (charset => 'iso-2022-jp')
      unless $s =~ /\x1B[^\x24\x28]
                   |\x1B\x24[^\x40B]
                   |\x1B\x28[^BJ]
                   |\x0E|\x0F/x;
    return (charset => 'iso-2022-jp-1')
      unless $s =~ /\x1B[^\x24\x28]
                   |\x1B\x24[^\x40B\x28]
                   |\x1B\x24\x28[^D]
                   |\x1B\x28[^BJ]
                   |\x0E|\x0F/x;
    return (charset => 'iso-2022-jp-3-plane1')
      unless $s =~ /\x1B[^\x24\x28]
                   |\x1B\x24[^\x28]     #[^B\x28]
                   |\x1B\x24\x28[^O]
                   |\x1B\x28[^B]
                   |\x0E|\x0F/x;
    return (charset => 'iso-2022-jp-3')
      unless $s =~ /\x1B[^\x24\x28]
                   |\x1B\x24[^\x28]     #[^B\x28]
                   |\x1B\x24\x28[^OP]
                   |\x1B\x28[^B]
                   |\x0E|\x0F/x;
    return (charset => 'iso-2022-kr')
      unless $s =~ /\x1B[^\x24]
                   |\x1B\x24[^\x29]
                   |\x1B\x24\x29[^C]/x;
    return (charset => 'iso-2022-jp-2')
      unless $s =~ /\x1B[^\x24\x28\x2E\x4E]
                   |\x1B\x24[^\x40AB\x28]
                   |\x1B\x24\x28[^CD]
                   |\x1B\x28[^BJ]
                   |\x1B\x2E[^AF]
                   |\x0E|\x0F/x;
    return (charset => 'iso-2022-cn')
      unless $s =~ /\x1B[^\x4E\x24]
                   |\x1B\x24[^\x29\x2A]
                   |\x1B\x24\x29[^AG]
                   |\x1B\x24\x2A[^H]/x;
    return (charset => 'iso-2022-cn-ext')
      unless $s =~ /\x1B[^\x4E\x4F\x24]
                   |\x1B\x24[^\x29\x2A]
                   |\x1B\x24\x29[^AEG]
                   |\x1B\x24\x2A[^HIJKLM]/x;
    return (charset => 'iso-2022-int-1')
      unless $s =~ /\x1B[^\x24\x28\x2D]
                   |\x1B\x24[^\x40AB\x28\x29]
                   |\x1B\x24\x28[^DGH]
                   |\x1B\x24\x29[^C]
                   |\x1B\x28[^BJ]
                   |\x1B\x2D[^AF]/x;
    return (charset => 'junet')
      unless $s =~ /\x1B[^\x24\x28\x2C]
                   |\x1B\x24[^\x28\x2C\x40-\x42]
                   |\x1B\x24[\x28\x2C][^\x20-\x7E]
                   |\x1B\x24[\x28\x2C][\x20-\x2F]+[^\x30-\x7E]
                   |\x1B[\x28\x2C][^\x20-\x7E]
                   |\x1B[\x28\x2C][\x20-\x2F]+[^\x30-\x7E]
                   |\x0E|\x0F/x;
    return (charset => 'x-iso-2022');
  } else {
    return (charset => 'us-ascii');
  }
}

sub _name_net_ascii_8bit ($) {
  my $name = shift; my $s = shift;
  return (charset => 'us-ascii') unless $s =~ /[\x1B\x0E\x0F\x80-\xFF]/;
  if ($s =~ /[\x80-\xFF]/) {
    if ($s =~ /[\xC0-\xFD][\x80-\xBF]*[\x80-\x8F]/) {
      if ($s =~ /\x1B/) {
        return (charset => 'x-junet8'); ## junet + UTF-8
      } else {
        return (charset => 'utf-8');
      }
    } elsif ($s =~ /\x1B/) {
      return (charset => 'x-iso-2022'); ## 8bit ISO 2022
    } else {
      return (charset => 'iso-8859-1');
    }
  } else {      ## 7bit ISO 2022
    return _name_7bit_iso2022 ($name, $s);
  }
}

sub _name_8bit_iso2022 ($$) {
  my $name = shift; my $s = shift;
  return (charset => 'us-ascii') unless $s =~ /[\x1B\x0E\x0F\x80-\xFF]/;
  if ($s =~ /[\x80-\xFF]/) {
    if ($s =~ /\x1B/) {
      return (charset => 'x-iso-2022'); ## 8bit ISO 2022
    } else {
      return (charset => 'iso-8859-1');
    }
  } else {      ## 7bit ISO 2022
    return _name_7bit_iso2022 ($name, $s);
  }
}

## Not completed.
## TODO: gb18030, cn-gb-12345
## TODO: _name_euc_gbf (cn-gb-12345, gb2312)
sub _name_euc_gb ($$) {
  my $name = shift; my $s = shift;
  if ($s =~ /[\x80-\xFF]/) {
    if ($s =~ /
                  (?:\G|[\x00-\x3F\x7F\x80\xFF])
                  (?:[\xA1-\xA9\xB0-\xFE][\xA1-\xFE]
                    |[\x40-\x7E])*
        (?:
          [\x81-\xA0\xAA-\xAF][\x40-\xFE]
         |[\xA1-\xFE][\x40-\xA0]
        )
      /x) {
      (charset => 'gbk');
    } elsif ($s =~ /
        (?:\xA2[\xA1-\xAA]
          |\xA6[\xE0-\xF5]
          |\xA8[\xBB-\xC0]
        )
          (?=(?:[\xA1-\xFE][\xA1-\xFE])*(?:[\x00-\xA0\xFF]|\z))
      /x) {
      (charset => 'gbk');
    } elsif ($s =~ /
        (?:\xA3\xE7|\xA7[\xDD-\xF2]
          |\xA8[\xBB-\xC0]
          |[\xAA-\xAF\xF8-\xFE][\xA1-\xFE]
        )
          (?=(?:[\xA1-\xFE][\xA1-\xFE])*(?:[\x00-\xA0\xFF]|\z))
      /x) {
      (charset => 'cn-gb-isoir165', 'charset-edition' => 1992);
    } elsif ($s =~ /\xEF\xF1    ## Typo bug of GB 2312
          (?=(?:[\xA1-\xFE][\xA1-\xFE])*(?:[\x00-\xA0\xFF]|\z))
      /x) {
      (charset => 'gb2312');
    } else {
      (charset => 'gb2312', 'charset-edition' => 1980);
    }
  } elsif ($s =~ /[\x0E\x0F]/) {
    (charset => 'gb2312');      ## Actually, this is not "gb2312"
  } else {
    _name_7bit_iso2022 ($name, $s);
  }
}

sub _name_euc_japan ($$) {
  my $name = shift; my $s = shift;
  if ($s =~ /[\x80-\xFF]/) {
    if ($s =~ /\x8F[\xA1\xA3-\xA5\xA8\xAC-\xAF\xEE-\xFE][\xA1-\xFE]/) {
      if ($s =~ /\x8F[\xA2\xA6\xA7\xA9-\xAB\xB0-\xED][\xA1-\xFE]/) {
      ## JIS X 0213 plane 2 + JIS X 0212
        (charset => 'x-euc-jisx0213-packed');
      } else {
        (charset => 'euc-jisx0213');
      }
    } elsif ($s =~ m{(?<![\x8E\x8F])    ## Not G2/G3 character
                    (?: ## JIS X 0213:2000
                       [\xA9-\xAF\xF5-\xFE][\xA1-\xFE]
                      |\xA2[\xAF-\xB9\xC2-\xC9\xD1-\xDB\xE9-\xF1\xFA-\xFD]
                      |\xA3[\xA1-\xAF\xBA-\xC0\xDB-\xE0\xFB-\xFE]
                      |\xA4[\xF4-\xFE]|\xA5[\xF7-\xFE]
                      |\xA6[\xB9-\xC0\xD9-\xFE]|\xA7[\xC2-\xD0\xF2-\xFE]
                      |\xA8[\xC1-\xFE]|\xCF[\xD4-\xFE]|\xF4[\xA7-\xFE]
                    )
                    (?=(?:[\xA1-\xFE][\xA1-\xFE])*(?:[\x00-\xA0\xFF]|\z))}x) {
      if ($s =~ /\x8F/) {       ## JIS X 0213 plane 1 + JIS X 0212
        (charset => 'x-euc-jisx0213-packed');
      } else {
        (charset => 'euc-jisx0213-plane1');
      }
    } else {
      (charset => 'euc-jp');
    }
  } elsif ($s =~ /\x0E|\x0F|\x1B[\x4E\x4F]/) {
    (charset => 'euc-jisx0213');        ## Actually, this is not euc-japan
  } else {
    _name_7bit_iso2022 ($name, $s);
  }
}

sub _name_shift_jis ($$) {
  my $name = shift; my $s = shift;
  if ($s =~ /[\x80-\xFF]/) {
    if ($s =~ /[\x0E\x0F\x1B]/) {
      (charset => 'x-sjis');
    } elsif ($s =~ /
                  (?:\G|[\x00-\x3F\x7F])
                  (?:[\x81-\x9F\xE0-\xFC][\x40-\x7E\x80-\xFC]
                    |[\x40-\x7E\xA1-\xDF])*
               [\xF0-\xFC][\x40-\x7E\x80-\xFC]
      /x) {
      (charset => 'shift_jisx0213');
    } elsif ($s =~ /
                  (?:\G|[\x00-\x3F\x7F])
                  (?:[\x81-\x9F\xE0-\xFC][\x40-\x7E\x80-\xFC]
                    |[\x40-\x7E\xA1-\xDF])*
              (?:
               [\x85-\x87\xEB-\xEF][\x40-\x7E\x80-\xFC]
              |\x81[\xAD-\xB7\xC0-\xC7\xCF-\xD9\xE9-\xEF\xF8-\xFB]
              |\x82[\x40-\x4E\x59-\x5F\x7A-\x80\x9B-\x9E\xF2-\xFC]
              |\x83[\x97-\x9E\xB7-\xBE\xD7-\xFC]
              |\x84[\x61-\x6F\x72-\x9E\xBF-\xFC]
              |\x88[\x40-\x9E]|\x98[\x73-\x9E]|\xEA[\xA5-\xFC]
              )
    /x) {
      (charset => 'shift_jisx0213-plane1');
    } else {
      (charset => 'shift_jis');
    }
  } elsif ($s =~ /[\x5C\x7E]/) {
    if ($s =~ /\x1B\x0E\x0F/) {
      (charset => 'x-sjis');    ## ISO 2022 with implied "ESC ( J"
        ## BUG: "ESC ( B foobar\aaa ESC ( J aiueo" also matchs this
    } else {
      (charset => 'jis_x0201');
    }
  } else {
    _name_7bit_iso2022 ($name, $s);
  }
}

sub _name_utf16be ($$) {
  shift; my $s = shift;
  if ($s =~ /[\xD8-\xDB][\x00-\xFF][\xDC-\xDF][\x00-\xFF]
             (?=(?:[\x00-\xFF][\x00-\xFF])*\z)/sx) {
    (charset => 'utf-16be');
  } elsif ($s =~ /[\x01-\xFF][\x00-\xFF]
             (?=(?:[\x00-\xFF][\x00-\xFF])*\z)/sx) {
    if ($s =~ /([^\x00\x03\x04\x23\x25\x30\xFE\xFF]
                     [\x00-\xFF]        # ^\x20\x22\x4E-\x9F\xF9\xFA
                  |\x03[^\x00-\x6F\xD0-\xFF]
                  #|\x20[^\x00-\x6F]
                  |\x25[^\x00-\x7F]
                  |\xFE[^\x30-\x4F]
                  |\xFF[^\x00-\xEF]
                  ## note 1 of RFC 1816 is ambitious, so block entire
                  ## is excepted
                    |\x30[\x00-\x3F]
                  )
             (?=(?:[\x00-\xFF][\x00-\xFF])*\z)/sx) {
      (charset => 'iso-10646-ucs-2');
    } else {
      (charset => 'iso-10646-j-1');
    }
  } elsif ($s =~ /\x00[\x80-\xFF]
             (?=(?:[\x00-\xFF][\x00-\xFF])*\z)/sx) {
    (charset => 'iso-10646-unicode-latin1');
  } else {
    (charset => 'iso-10646-ucs-basic');
  }
}

sub _name_utf32be ($$) {
  shift; my $s = shift;
  if ($s =~ /
    ([\x01-\x7F][\x00-\xFF]{3}
    |\x00[\x11-\xFF][\x00-\xFF][\x00-\xFF])
             (?=(?:[\x00-\xFF]{4})*\z)/sx) {
    (charset => 'iso-10646-ucs-4');
  } else {
    (charset => 'utf-32be');
  }
}

sub _utf8_on ($) {
  Encode::_utf8_on ($_[0]) if $Encode::VERSION;
}
sub _utf8_off ($) {
  Encode::_utf8_off ($_[0]) if $Encode::VERSION;
}

=head1 LICENSE

Copyright 2002 wakaba E<lt>w@suika.fam.cxE<gt>.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.

=head1 CHANGE

See F<ChangeLog>.
$Date: 2002/07/21 03:25:23 $

=cut

1;
1	wakaba	1.1
2			=head1 NAME
3
4			Message::MIME::Charset Perl module
5
6			=head1 DESCRIPTION
7
8			Perl module for MIME charset.
9
10			=cut
11
12	wakaba	1.10	## NOTE: You should not require/use other module (even it
13			## is part of Message::* Perl Modules) as far as possible,
14			## to be able to use this module (M::M::Charset) from
15			## other (non-Message::*) modules.
16
17	wakaba	1.1	package Message::MIME::Charset;
18			use strict;
19	wakaba	1.12	use vars qw(%CHARSET %MSNAME2IANANAME %REG $VERSION);
20	wakaba	1.13	$VERSION=do{my @r=(q$Revision: 1.12 $=~/\d+/g);sprintf "%d."."%02d" x $#r,@r};
21	wakaba	1.1
22	wakaba	1.9	&_builtin_charset;
23			sub _builtin_charset () {
24	wakaba	1.4
25			$CHARSET{'*DEFAULT'} = {
26			preferred_name => '',
27
28			encoder => sub { $_[1] },
29			decoder => sub { $_[1] },
30
31			mime_text => 1, ## Suitability in use as MIME text/* charset
32			#accept_cte => [qw/7bit .../],
33			cte_7bit_preferred => 'quoted-printable',
34			};
35			$CHARSET{'default'} = $CHARSET{'DEFAULT'};
36
37			$CHARSET{'us-ascii'} = {
38			preferred_name => 'us-ascii',
39
40			encoder => sub { $_[1] },
41			decoder => sub { $_[1] },
42	wakaba	1.5
43			mime_text => 1,
44	wakaba	1.13	cte_7bit_preferred => 'quoted-printable',
45	wakaba	1.4	};
46
47			$CHARSET{'iso-2022-int-1'} = {
48			preferred_name => 'iso-2022-int-1',
49
50			encoder => sub { $_[1] },
51			decoder => sub { $_[1] },
52	wakaba	1.5
53			mime_text => 1,
54	wakaba	1.4	};
55
56			$CHARSET{'unknown-8bit'} = {
57			preferred_name => 'unknown-8bit',
58
59			encoder => sub { $_[1] },
60			decoder => sub { $_[1] },
61
62	wakaba	1.13	mime_text => 1,
63			cte_7bit_preferred => 'base64',
64			};
65
66			$CHARSET{'x-unknown'} = {
67			preferred_name => 'x-unknown',
68
69			encoder => sub { $_[1] },
70			decoder => sub { $_[1] },
71
72			mime_text => 0,
73			cte_7bit_preferred => 'base64',
74			};
75
76			$CHARSET{'*undef'} = {
77			preferred_name => '',
78
79			#encoder => sub { $_[1] },
80			#decoder => sub { $_[1] },
81
82	wakaba	1.4	mime_text => 0,
83	wakaba	1.6	cte_7bit_preferred => 'base64',
84	wakaba	1.4	};
85
86	wakaba	1.9	} # /builtin_charset
87
88			my %_MINIMUMIZER = (
89			'euc-jp' => \&_name_euc_japan,
90			'euc-jisx0213' => \&_name_euc_japan,
91			'euc-jisx0213-plane1' => \&_name_euc_japan,
92			'x-euc-jisx0213-packed' => \&_name_euc_japan,
93	wakaba	1.11	'x-iso-2022' => \&_name_8bit_iso2022,
94			'iso-2022-cn' => \&_name_8bit_iso2022,
95			'iso-2022-cn-ext' => \&_name_8bit_iso2022,
96	wakaba	1.9	'iso-2022-int-1' => \&_name_net_ascii_8bit,
97	wakaba	1.11	'iso-2022-jp' => \&_name_8bit_iso2022,
98			'iso-2022-jp-1' => \&_name_8bit_iso2022,
99			'iso-2022-jp-2' => \&_name_8bit_iso2022,
100			'iso-2022-jp-3' => \&_name_8bit_iso2022,
101			'iso-2022-jp-3-plane1' => \&_name_8bit_iso2022,
102			'iso-2022-kr' => \&_name_8bit_iso2022,
103			'iso-8859-1' => \&_name_8bit_iso2022,
104	wakaba	1.9	'iso-10646-j-1' => \&_name_utf16be,
105			'iso-10646-ucs-2' => \&_name_utf16be,
106			'iso-10646-ucs-4' => \&_name_utf32be,
107			'iso-10646-ucs-basic' => \&_name_utf16be,
108			'iso-10646-unicode-latin1' => \&_name_utf16be,
109			jis_x0201 => \&_name_shift_jis,
110	wakaba	1.11	junet => \&_name_8bit_iso2022,
111	wakaba	1.9	'x-junet8' => \&_name_net_ascii_8bit,
112			shift_jis => \&_name_shift_jis,
113			shift_jisx0213 => \&_name_shift_jis,
114			'shift_jisx0213-plane1' => \&_name_shift_jis,
115			'x-sjis' => \&_name_shift_jis,
116			'us-ascii' => \&_name_net_ascii_8bit,
117			'utf-8' => \&_name_net_ascii_8bit,
118			'utf-16be' => \&_name_utf16be,
119			'utf-32be' => \&_name_utf32be,
120			);
121
122	wakaba	1.12	%MSNAME2IANANAME = (
123			'iso-2022-jp' => 'x-iso2022jp-cp932',
124			'ks_c_5601-1987' => 'windows-949',
125			);
126
127	wakaba	1.4	sub make_charset ($%) {
128			my $name = shift;
129			return unless $name; ## Note: charset "0" is not supported.
130			my %definition = @_;
131	wakaba	1.6
132			$definition{preferred_name} \|\|= $name;
133	wakaba	1.4	if ($definition{preferred_name} ne $name
134			&& ref $CHARSET{$definition{preferred_name}}) {
135			## New charset is an alias of defined charset,
136			$CHARSET{$name} = $CHARSET{$definition{preferred_name}};
137			return;
138			} elsif ($definition{alias_of} && ref $CHARSET{$definition{alias_of}}) {
139			## New charset is an alias of defined charset,
140			$CHARSET{$name} = $CHARSET{$definition{alias_of}};
141			return;
142			}
143			$CHARSET{$name} = \%definition;
144
145			## Set default values
146	wakaba	1.6	#$definition{encoder} \|\|= sub { $_[1] };
147			#$definition{decoder} \|\|= sub { $_[1] };
148	wakaba	1.4
149			$definition{mime_text} = 0 unless defined $definition{mime_text};
150			$definition{cte_7bit_preferred} = 'base64'
151			unless defined $definition{cte_7bit_preferred};
152			}
153	wakaba	1.1
154			sub encode ($$) {
155			my ($charset, $s) = (lc shift, shift);
156	wakaba	1.13	my $c = ref $CHARSET{$charset}->{encoder}? $charset: '*undef';
157			if (ref $CHARSET{$c}->{encoder}) {
158			my ($t, %r) = &{$CHARSET{$c}->{encoder}} ($charset, $s);
159			unless (defined $r{success}) {
160			$r{success} = 1;
161			}
162			return ($t, %r);
163	wakaba	1.1	}
164	wakaba	1.5	($s, success => 0);
165	wakaba	1.1	}
166
167			sub decode ($$) {
168			my ($charset, $s) = (lc shift, shift);
169	wakaba	1.13	my $c = ref $CHARSET{$charset}->{decoder}? $charset: '*undef';
170			if (ref $CHARSET{$c}->{decoder}) {
171			my ($t, %r) = &{$CHARSET{$c}->{decoder}} ($charset, $s);
172			unless (defined $r{success}) {
173			$r{success} = 1;
174			}
175			return ($t, %r);
176	wakaba	1.1	}
177	wakaba	1.13	($s, success => 0);
178	wakaba	1.1	}
179
180			sub name_normalize ($) {
181			my $name = lc shift;
182	wakaba	1.4	$CHARSET{$name}->{preferred_name} \|\| $name;
183	wakaba	1.1	}
184
185	wakaba	1.6	sub name_minimumize ($$) {
186			my ($charset, $s) = (lc shift, shift);
187	wakaba	1.9	if (ref $CHARSET{$charset}->{name_minimumizer} eq 'CODE') {
188	wakaba	1.6	return &{$CHARSET{$charset}->{name_minimumizer}} ($charset, $s);
189	wakaba	1.9	} elsif (ref $_MINIMUMIZER{$charset}) {
190			return &{$_MINIMUMIZER{$charset}} ($charset, $s);
191	wakaba	1.13	} elsif (ref $CHARSET{'*undef'}->{name_minimumizer} eq 'CODE') {
192			return &{$CHARSET{'*undef'}->{name_minimumizer}} ($charset, $s);
193	wakaba	1.9	}
194			(charset => $charset);
195			}
196
197	wakaba	1.12	sub msname2iananame ($) {
198			my $mscharset = shift;
199			$MSNAME2IANANAME{$mscharset} \|\| $mscharset;
200			}
201
202	wakaba	1.9	sub _name_7bit_iso2022 ($$) {shift;
203			my $s = shift;
204			if ($s =~ /[\x0E\x0F\x1B]/) {
205			return (charset => 'iso-2022-jp')
206			unless $s =~ /\x1B[^\x24\x28]
207			\|\x1B\x24[^\x40B]
208			\|\x1B\x28[^BJ]
209			\|\x0E\|\x0F/x;
210			return (charset => 'iso-2022-jp-1')
211			unless $s =~ /\x1B[^\x24\x28]
212			\|\x1B\x24[^\x40B\x28]
213			\|\x1B\x24\x28[^D]
214			\|\x1B\x28[^BJ]
215			\|\x0E\|\x0F/x;
216			return (charset => 'iso-2022-jp-3-plane1')
217			unless $s =~ /\x1B[^\x24\x28]
218			\|\x1B\x24[^\x28] #[^B\x28]
219			\|\x1B\x24\x28[^O]
220			\|\x1B\x28[^B]
221			\|\x0E\|\x0F/x;
222			return (charset => 'iso-2022-jp-3')
223			unless $s =~ /\x1B[^\x24\x28]
224			\|\x1B\x24[^\x28] #[^B\x28]
225			\|\x1B\x24\x28[^OP]
226			\|\x1B\x28[^B]
227			\|\x0E\|\x0F/x;
228			return (charset => 'iso-2022-kr')
229			unless $s =~ /\x1B[^\x24]
230			\|\x1B\x24[^\x29]
231			\|\x1B\x24\x29[^C]/x;
232			return (charset => 'iso-2022-jp-2')
233			unless $s =~ /\x1B[^\x24\x28\x2E\x4E]
234			\|\x1B\x24[^\x40AB\x28]
235			\|\x1B\x24\x28[^CD]
236			\|\x1B\x28[^BJ]
237			\|\x1B\x2E[^AF]
238			\|\x0E\|\x0F/x;
239			return (charset => 'iso-2022-cn')
240			unless $s =~ /\x1B[^\x4E\x24]
241			\|\x1B\x24[^\x29\x2A]
242			\|\x1B\x24\x29[^AG]
243			\|\x1B\x24\x2A[^H]/x;
244			return (charset => 'iso-2022-cn-ext')
245			unless $s =~ /\x1B[^\x4E\x4F\x24]
246			\|\x1B\x24[^\x29\x2A]
247			\|\x1B\x24\x29[^AEG]
248			\|\x1B\x24\x2A[^HIJKLM]/x;
249			return (charset => 'iso-2022-int-1')
250			unless $s =~ /\x1B[^\x24\x28\x2D]
251			\|\x1B\x24[^\x40AB\x28\x29]
252			\|\x1B\x24\x28[^DGH]
253			\|\x1B\x24\x29[^C]
254			\|\x1B\x28[^BJ]
255			\|\x1B\x2D[^AF]/x;
256			return (charset => 'junet')
257			unless $s =~ /\x1B[^\x24\x28\x2C]
258			\|\x1B\x24[^\x28\x2C\x40-\x42]
259			\|\x1B\x24[\x28\x2C][^\x20-\x7E]
260			\|\x1B\x24[\x28\x2C][\x20-\x2F]+[^\x30-\x7E]
261			\|\x1B[\x28\x2C][^\x20-\x7E]
262			\|\x1B[\x28\x2C][\x20-\x2F]+[^\x30-\x7E]
263			\|\x0E\|\x0F/x;
264			return (charset => 'x-iso-2022');
265			} else {
266			return (charset => 'us-ascii');
267	wakaba	1.6	}
268			}
269
270	wakaba	1.9	sub _name_net_ascii_8bit ($) {
271			my $name = shift; my $s = shift;
272	wakaba	1.8	return (charset => 'us-ascii') unless $s =~ /[\x1B\x0E\x0F\x80-\xFF]/;
273			if ($s =~ /[\x80-\xFF]/) {
274			if ($s =~ /[\xC0-\xFD][\x80-\xBF]*[\x80-\x8F]/) {
275			if ($s =~ /\x1B/) {
276	wakaba	1.9	return (charset => 'x-junet8'); ## junet + UTF-8
277	wakaba	1.8	} else {
278			return (charset => 'utf-8');
279			}
280			} elsif ($s =~ /\x1B/) {
281	wakaba	1.9	return (charset => 'x-iso-2022'); ## 8bit ISO 2022
282			} else {
283			return (charset => 'iso-8859-1');
284			}
285			} else { ## 7bit ISO 2022
286			return _name_7bit_iso2022 ($name, $s);
287			}
288			}
289
290	wakaba	1.11	sub _name_8bit_iso2022 ($$) {
291	wakaba	1.9	my $name = shift; my $s = shift;
292			return (charset => 'us-ascii') unless $s =~ /[\x1B\x0E\x0F\x80-\xFF]/;
293			if ($s =~ /[\x80-\xFF]/) {
294			if ($s =~ /\x1B/) {
295			return (charset => 'x-iso-2022'); ## 8bit ISO 2022
296	wakaba	1.8	} else {
297			return (charset => 'iso-8859-1');
298			}
299	wakaba	1.9	} else { ## 7bit ISO 2022
300			return _name_7bit_iso2022 ($name, $s);
301			}
302			}
303
304			## Not completed.
305			## TODO: gb18030, cn-gb-12345
306			## TODO: _name_euc_gbf (cn-gb-12345, gb2312)
307			sub _name_euc_gb ($$) {
308			my $name = shift; my $s = shift;
309			if ($s =~ /[\x80-\xFF]/) {
310			if ($s =~ /
311			(?:\G\|[\x00-\x3F\x7F\x80\xFF])
312			(?:[\xA1-\xA9\xB0-\xFE][\xA1-\xFE]
313			\|[\x40-\x7E])*
314			(?:
315			[\x81-\xA0\xAA-\xAF][\x40-\xFE]
316			\|[\xA1-\xFE][\x40-\xA0]
317			)
318			/x) {
319			(charset => 'gbk');
320			} elsif ($s =~ /
321			(?:\xA2[\xA1-\xAA]
322			\|\xA6[\xE0-\xF5]
323			\|\xA8[\xBB-\xC0]
324			)
325			(?=(?:[\xA1-\xFE][\xA1-\xFE])*(?:[\x00-\xA0\xFF]\|\z))
326			/x) {
327			(charset => 'gbk');
328			} elsif ($s =~ /
329			(?:\xA3\xE7\|\xA7[\xDD-\xF2]
330			\|\xA8[\xBB-\xC0]
331			\|[\xAA-\xAF\xF8-\xFE][\xA1-\xFE]
332			)
333			(?=(?:[\xA1-\xFE][\xA1-\xFE])*(?:[\x00-\xA0\xFF]\|\z))
334			/x) {
335			(charset => 'cn-gb-isoir165', 'charset-edition' => 1992);
336			} elsif ($s =~ /\xEF\xF1 ## Typo bug of GB 2312
337			(?=(?:[\xA1-\xFE][\xA1-\xFE])*(?:[\x00-\xA0\xFF]\|\z))
338			/x) {
339			(charset => 'gb2312');
340			} else {
341			(charset => 'gb2312', 'charset-edition' => 1980);
342			}
343			} elsif ($s =~ /[\x0E\x0F]/) {
344			(charset => 'gb2312'); ## Actually, this is not "gb2312"
345			} else {
346	wakaba	1.11	_name_7bit_iso2022 ($name, $s);
347	wakaba	1.9	}
348			}
349
350			sub _name_euc_japan ($$) {
351			my $name = shift; my $s = shift;
352			if ($s =~ /[\x80-\xFF]/) {
353			if ($s =~ /\x8F[\xA1\xA3-\xA5\xA8\xAC-\xAF\xEE-\xFE][\xA1-\xFE]/) {
354			if ($s =~ /\x8F[\xA2\xA6\xA7\xA9-\xAB\xB0-\xED][\xA1-\xFE]/) {
355			## JIS X 0213 plane 2 + JIS X 0212
356			(charset => 'x-euc-jisx0213-packed');
357			} else {
358			(charset => 'euc-jisx0213');
359			}
360			} elsif ($s =~ m{(?<![\x8E\x8F]) ## Not G2/G3 character
361			(?: ## JIS X 0213:2000
362			[\xA9-\xAF\xF5-\xFE][\xA1-\xFE]
363			\|\xA2[\xAF-\xB9\xC2-\xC9\xD1-\xDB\xE9-\xF1\xFA-\xFD]
364			\|\xA3[\xA1-\xAF\xBA-\xC0\xDB-\xE0\xFB-\xFE]
365			\|\xA4[\xF4-\xFE]\|\xA5[\xF7-\xFE]
366			\|\xA6[\xB9-\xC0\xD9-\xFE]\|\xA7[\xC2-\xD0\xF2-\xFE]
367			\|\xA8[\xC1-\xFE]\|\xCF[\xD4-\xFE]\|\xF4[\xA7-\xFE]
368			)
369			(?=(?:[\xA1-\xFE][\xA1-\xFE])*(?:[\x00-\xA0\xFF]\|\z))}x) {
370			if ($s =~ /\x8F/) { ## JIS X 0213 plane 1 + JIS X 0212
371			(charset => 'x-euc-jisx0213-packed');
372			} else {
373			(charset => 'euc-jisx0213-plane1');
374			}
375			} else {
376			(charset => 'euc-jp');
377			}
378			} elsif ($s =~ /\x0E\|\x0F\|\x1B[\x4E\x4F]/) {
379			(charset => 'euc-jisx0213'); ## Actually, this is not euc-japan
380			} else {
381	wakaba	1.11	_name_7bit_iso2022 ($name, $s);
382	wakaba	1.9	}
383			}
384
385			sub _name_shift_jis ($$) {
386			my $name = shift; my $s = shift;
387			if ($s =~ /[\x80-\xFF]/) {
388			if ($s =~ /[\x0E\x0F\x1B]/) {
389			(charset => 'x-sjis');
390			} elsif ($s =~ /
391			(?:\G\|[\x00-\x3F\x7F])
392			(?:[\x81-\x9F\xE0-\xFC][\x40-\x7E\x80-\xFC]
393			\|[\x40-\x7E\xA1-\xDF])*
394			[\xF0-\xFC][\x40-\x7E\x80-\xFC]
395			/x) {
396			(charset => 'shift_jisx0213');
397			} elsif ($s =~ /
398			(?:\G\|[\x00-\x3F\x7F])
399			(?:[\x81-\x9F\xE0-\xFC][\x40-\x7E\x80-\xFC]
400			\|[\x40-\x7E\xA1-\xDF])*
401			(?:
402			[\x85-\x87\xEB-\xEF][\x40-\x7E\x80-\xFC]
403			\|\x81[\xAD-\xB7\xC0-\xC7\xCF-\xD9\xE9-\xEF\xF8-\xFB]
404			\|\x82[\x40-\x4E\x59-\x5F\x7A-\x80\x9B-\x9E\xF2-\xFC]
405			\|\x83[\x97-\x9E\xB7-\xBE\xD7-\xFC]
406			\|\x84[\x61-\x6F\x72-\x9E\xBF-\xFC]
407			\|\x88[\x40-\x9E]\|\x98[\x73-\x9E]\|\xEA[\xA5-\xFC]
408			)
409			/x) {
410			(charset => 'shift_jisx0213-plane1');
411			} else {
412			(charset => 'shift_jis');
413			}
414			} elsif ($s =~ /[\x5C\x7E]/) {
415			if ($s =~ /\x1B\x0E\x0F/) {
416			(charset => 'x-sjis'); ## ISO 2022 with implied "ESC ( J"
417			## BUG: "ESC ( B foobar\aaa ESC ( J aiueo" also matchs this
418			} else {
419			(charset => 'jis_x0201');
420			}
421			} else {
422	wakaba	1.11	_name_7bit_iso2022 ($name, $s);
423	wakaba	1.9	}
424			}
425
426			sub _name_utf16be ($$) {
427			shift; my $s = shift;
428			if ($s =~ /[\xD8-\xDB][\x00-\xFF][\xDC-\xDF][\x00-\xFF]
429			(?=(?:[\x00-\xFF][\x00-\xFF])*\z)/sx) {
430			(charset => 'utf-16be');
431			} elsif ($s =~ /[\x01-\xFF][\x00-\xFF]
432			(?=(?:[\x00-\xFF][\x00-\xFF])*\z)/sx) {
433			if ($s =~ /([^\x00\x03\x04\x23\x25\x30\xFE\xFF]
434			[\x00-\xFF] # ^\x20\x22\x4E-\x9F\xF9\xFA
435			\|\x03[^\x00-\x6F\xD0-\xFF]
436			#\|\x20[^\x00-\x6F]
437			\|\x25[^\x00-\x7F]
438			\|\xFE[^\x30-\x4F]
439			\|\xFF[^\x00-\xEF]
440			## note 1 of RFC 1816 is ambitious, so block entire
441			## is excepted
442			\|\x30[\x00-\x3F]
443			)
444			(?=(?:[\x00-\xFF][\x00-\xFF])*\z)/sx) {
445			(charset => 'iso-10646-ucs-2');
446			} else {
447			(charset => 'iso-10646-j-1');
448			}
449			} elsif ($s =~ /\x00[\x80-\xFF]
450			(?=(?:[\x00-\xFF][\x00-\xFF])*\z)/sx) {
451			(charset => 'iso-10646-unicode-latin1');
452			} else {
453			(charset => 'iso-10646-ucs-basic');
454			}
455			}
456
457			sub _name_utf32be ($$) {
458			shift; my $s = shift;
459			if ($s =~ /
460			([\x01-\x7F][\x00-\xFF]{3}
461			\|\x00[\x11-\xFF][\x00-\xFF][\x00-\xFF])
462			(?=(?:[\x00-\xFF]{4})*\z)/sx) {
463			(charset => 'iso-10646-ucs-4');
464			} else {
465			(charset => 'utf-32be');
466	wakaba	1.8	}
467			}
468
469	wakaba	1.13	sub _utf8_on ($) {
470			Encode::_utf8_on ($_[0]) if $Encode::VERSION;
471			}
472			sub _utf8_off ($) {
473			Encode::_utf8_off ($_[0]) if $Encode::VERSION;
474			}
475
476	wakaba	1.1	=head1 LICENSE
477
478			Copyright 2002 wakaba E<lt>w@suika.fam.cxE<gt>.
479
480			This program is free software; you can redistribute it and/or modify
481			it under the terms of the GNU General Public License as published by
482			the Free Software Foundation; either version 2 of the License, or
483			(at your option) any later version.
484
485			This program is distributed in the hope that it will be useful,
486			but WITHOUT ANY WARRANTY; without even the implied warranty of
487			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
488			GNU General Public License for more details.
489
490			You should have received a copy of the GNU General Public License
491			along with this program; see the file COPYING. If not, write to
492			the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
493			Boston, MA 02111-1307, USA.
494
495			=head1 CHANGE
496
497			See F<ChangeLog>.
498	wakaba	1.13	$Date: 2002/07/21 03:25:23 $
499	wakaba	1.1
500			=cut
501
502			1;