[p5sagit/p5-mst-13.2.git] / ext / Encode / Encode.pm

package Encode;

$VERSION = 0.01;

require DynaLoader;
require Exporter;

@ISA = qw(Exporter DynaLoader);

@EXPORT_OK =
    qw(
       bytes_to_utf8
       utf8_to_bytes
       chars_to_utf8
       utf8_to_chars
       utf8_to_chars_check
       bytes_to_chars
       chars_to_bytes
       from_to
       is_utf8
       on_utf8
       off_utf8
       utf_to_utf
       encodings
      );

bootstrap Encode ();

=pod

=head1 NAME

Encode - character encodings

=head2 TERMINOLOGY

=over

=item *

I<char>: a character in the range 0..maxint (at least 2**32-1)

=item *

I<byte>: a character in the range 0..255

=back

The marker [INTERNAL] marks Internal Implementation Details, in
general meant only for those who think they know what they are doing,
and such details may change in future releases.

=head2 bytes

=over 4

=item *

        bytes_to_utf8(STRING [, FROM])

The bytes in STRING are recoded in-place into UTF-8.  If no FROM is
specified the bytes are expected to be encoded in US-ASCII or ISO
8859-1 (Latin 1).  Returns the new size of STRING, or C<undef> if
there's a failure.

[INTERNAL] Also the UTF-8 flag of STRING is turned on.

=item *

        utf8_to_bytes(STRING [, TO [, CHECK]])

The UTF-8 in STRING is decoded in-place into bytes.  If no TO encoding
is specified the bytes are expected to be encoded in US-ASCII or ISO
8859-1 (Latin 1).  Returns the new size of STRING, or C<undef> if
there's a failure.

What if there are characters > 255?  What if the UTF-8 in STRING is
malformed?  See L</"Handling Malformed Data">.

[INTERNAL] The UTF-8 flag of STRING is not checked.

=back

=head2 chars

=over 4

=item *

        chars_to_utf8(STRING)

The chars in STRING are encoded in-place into UTF-8.  Returns the new
size of STRING, or C<undef> if there's a failure.

No assumptions are made on the encoding of the chars.  If you want to
assume that the chars are Unicode and to trap illegal Unicode
characters, you must use C<from_to('Unicode', ...)>.

[INTERNAL] Also the UTF-8 flag of STRING is turned on.

=over 4

=item *

        utf8_to_chars(STRING)

The UTF-8 in STRING is decoded in-place into chars.  Returns the new
size of STRING, or C<undef> if there's a failure.

If the UTF-8 in STRING is malformed C<undef> is returned, and also an
optional lexical warning (category utf8) is given.

[INTERNAL] The UTF-8 flag of STRING is not checked.

=item *

        utf8_to_chars_check(STRING [, CHECK])

(Note that special naming of this interface since a two-argument
utf8_to_chars() has different semantics.)

The UTF-8 in STRING is decoded in-place into chars.  Returns the new
size of STRING, or C<undef> if there is a failure.

If the UTF-8 in STRING is malformed?  See L</"Handling Malformed Data">.

[INTERNAL] The UTF-8 flag of STRING is not checked.

=back

=head2 chars With Encoding

=over 4

=item *

        chars_to_utf8(STRING, FROM [, CHECK])

The chars in STRING encoded in FROM are recoded in-place into UTF-8.
Returns the new size of STRING, or C<undef> if there's a failure.

No assumptions are made on the encoding of the chars.  If you want to
assume that the chars are Unicode and to trap illegal Unicode
characters, you must use C<from_to('Unicode', ...)>.

[INTERNAL] Also the UTF-8 flag of STRING is turned on.

=item *

        utf8_to_chars(STRING, TO [, CHECK])

The UTF-8 in STRING is decoded in-place into chars encoded in TO.
Returns the new size of STRING, or C<undef> if there's a failure.

If the UTF-8 in STRING is malformed?  See L</"Handling Malformed Data">.

[INTERNAL] The UTF-8 flag of STRING is not checked.

=item *

	bytes_to_chars(STRING, FROM [, CHECK])

The bytes in STRING encoded in FROM are recoded in-place into chars.
Returns the new size of STRING in bytes, or C<undef> if there's a
failure.

If the mapping is impossible?  See L</"Handling Malformed Data">.

=item *

	chars_to_bytes(STRING, TO [, CHECK])

The chars in STRING are recoded in-place to bytes encoded in TO.
Returns the new size of STRING in bytes, or C<undef> if there's a
failure.

If the mapping is impossible?  See L</"Handling Malformed Data">.

=item *

        from_to(STRING, FROM, TO [, CHECK])

The chars in STRING encoded in FROM are recoded in-place into TO.
Returns the new size of STRING, or C<undef> if there's a failure.

If mapping between the encodings is impossible?
See L</"Handling Malformed Data">.

[INTERNAL] If TO is UTF-8, also the UTF-8 flag of STRING is turned on.

=back

=head2 Testing For UTF-8

=over 4

=item *

        is_utf8(STRING [, CHECK])

[INTERNAL] Test whether the UTF-8 flag is turned on in the STRING.
If CHECK is true, also checks the data in STRING for being
well-formed UTF-8.  Returns true if successful, false otherwise.

=back

=head2 Toggling UTF-8-ness

=over 4

=item *

        on_utf8(STRING)

[INTERNAL] Turn on the UTF-8 flag in STRING.  The data in STRING is
B<not> checked for being well-formed UTF-8.  Do not use unless you
B<know> that the STRING is well-formed UTF-8.  Returns the previous
state of the UTF-8 flag (so please don't test the return value as
I<not> success or failure), or C<undef> if STRING is not a string.

=item *

        off_utf8(STRING)

[INTERNAL] Turn off the UTF-8 flag in STRING.  Do not use frivolously.
Returns the previous state of the UTF-8 flag (so please don't test the
return value as I<not> success or failure), or C<undef> if STRING is
not a string.

=back

=head2 UTF-16 and UTF-32 Encodings

=over 4

=item *

        utf_to_utf(STRING, FROM, TO [, CHECK])

The data in STRING is converted from Unicode Transfer Encoding FROM to
Unicode Transfer Encoding TO.  Both FROM and TO may be any of the
following tags (case-insensitive, with or without 'utf' or 'utf-' prefix):

        tag             meaning

        '7'             UTF-7
        '8'             UTF-8
        '16be'          UTF-16 big-endian
        '16le'          UTF-16 little-endian
        '16'            UTF-16 native-endian
        '32be'          UTF-32 big-endian
        '32le'          UTF-32 little-endian
        '32'            UTF-32 native-endian

UTF-16 is also known as UCS-2, 16 bit or 2-byte chunks, and UTF-32 as
UCS-4, 32-bit or 4-byte chunks.  Returns the new size of STRING, or
C<undef> is there's a failure.

If FROM is UTF-8 and the UTF-8 in STRING is malformed?  See
L</"Handling Malformed Data">.

[INTERNAL] Even if CHECK is true and FROM is UTF-8, the UTF-8 flag of
STRING is not checked.  If TO is UTF-8, also the UTF-8 flag of STRING is
turned on.  Identical FROM and TO are fine.

=back

=head2 Handling Malformed Data

If CHECK is not set, C<undef> is returned.  If the data is supposed to
be UTF-8, an optional lexical warning (category utf8) is given.  If
CHECK is true but not a code reference, dies.  If CHECK is a code
reference, it is called with the arguments

	(MALFORMED_STRING, STRING_FROM_SO_FAR, STRING_TO_SO_FAR)

Two return values are expected from the call: the string to be used in
the result string in place of the malformed section, and the length of
the malformed section in bytes.

=cut

sub bytes_to_utf8 {
    &_bytes_to_utf8;
}

sub utf8_to_bytes {
    &_utf8_to_bytes;
}

sub chars_to_utf8 {
    &C_to_utf8;
}

sub utf8_to_chars {
    &_utf8_to_chars;
}

sub utf8_to_chars_check {
    &_utf8_to_chars_check;
}

sub bytes_to_chars {
    &_bytes_to_chars;
}

sub chars_to_bytes {
    &_chars_to_bytes;
}

sub is_utf8 {
    &_is_utf8;
}

sub on_utf8 {
    &_on_utf8;
}

sub off_utf8 {
    &_off_utf8;
}

sub utf_to_utf {
    &_utf_to_utf;
}

use Carp;

sub from_to
{
 my ($string,$from,$to,$check) = @_;
 my $f = __PACKAGE__->getEncoding($from);
 croak("Unknown encoding '$from'") unless $f;
 my $t = __PACKAGE__->getEncoding($to);
 croak("Unknown encoding '$to'") unless $t;
 my $uni = $f->toUnicode($string,$check);
 return undef if ($check && length($string));
 $string = $t->fromUnicode($uni,$check);
 return undef if ($check && length($uni));
 return length($_[0] = $string);
}

# The global hash is declared in XS code
$encoding{Unicode}    = bless({},'Encode::Unicode');
$encoding{iso10646-1} = bless({},'Encode::iso10646_1');

sub encodings
{
 my ($class) = @_;
 foreach my $dir (@INC)
  {
   if (opendir(my $dh,"$dir/Encode"))
    {
     while (defined(my $name = readdir($dh)))
      {
       if ($name =~ /^(.*)\.enc$/)
        {
         next if exists $encoding{$1};
         $encoding{$1} = "$dir/$name";
        }
      }
     closedir($dh);
    }
  }
 return keys %encoding;
}

sub loadEncoding
{
 my ($class,$name,$file) = @_;
 if (open(my $fh,$file))
  {
   my $type;
   while (1)
    {
     my $line = <$fh>;
     $type = substr($line,0,1);
     last unless $type eq '#';
    }
   $class .= ('::'.(($type eq 'E') ? 'Escape' : 'Table'));
   warn "Loading $file";
   return $class->read($fh,$name,$type);
  }
 else
  {
   return undef;
  }
}

sub getEncoding
{
 my ($class,$name) = @_;
 my $enc;
 unless (ref($enc = $encoding{$name}))
  {
   $enc = $class->loadEncoding($name,$enc) if defined $enc;
   unless (ref($enc))
    {
     foreach my $dir (@INC)
      {
       last if ($enc = $class->loadEncoding($name,"$dir/Encode/$name.enc"));
      }
    }
   $encoding{$name} = $enc;
  }
 return $enc;
}

package Encode::Unicode;

# Dummy package that provides the encode interface

sub name { 'Unicode' }

sub toUnicode   { $_[1] }

sub fromUnicode { $_[1] }

package Encode::Table;

sub read
{
 my ($class,$fh,$name,$type) = @_;
 my $rep = $class->can("rep_$type");
 my ($def,$sym,$pages) = split(/\s+/,scalar(<$fh>));
 my @touni;
 my %fmuni;
 my $count = 0;
 $def = hex($def);
 while ($pages--)
  {
   my $line = <$fh>;
   chomp($line);
   my $page = hex($line);
   my @page;
   my $ch = $page * 256;
   for (my $i = 0; $i < 16; $i++)
    {
     my $line = <$fh>;
     for (my $j = 0; $j < 16; $j++)
      {
       my $val = hex(substr($line,0,4,''));
       if ($val || !$ch)
        {
         my $uch = chr($val);
         push(@page,$uch);
         $fmuni{$uch} = $ch;
         $count++;
        }
       else
        {
         push(@page,undef);
        }
       $ch++;
      }
    }
   $touni[$page] = \@page;
  }

 return bless {Name  => $name,
               Rep   => $rep,
               ToUni => \@touni,
               FmUni => \%fmuni,
               Def   => $def,
               Num   => $count,
              },$class;
}

sub name { shift->{'Name'} }

sub rep_S { 'C' }

sub rep_D { 'n' }

sub rep_M { ($_[0] > 255) ? 'n' : 'C' }

sub representation
{
 my ($obj,$ch) = @_;
 $ch = 0 unless @_ > 1;
 $obj-{'Rep'}->($ch);
}

sub toUnicode
{
 my ($obj,$str,$chk) = @_;
 my $rep   = $obj->{'Rep'};
 my $touni = $obj->{'ToUni'};
 my $uni   = '';
 while (length($str))
  {
   my $ch = ord(substr($str,0,1,''));
   my $x;
   if (&$rep($ch) eq 'C')
    {
     $x = $touni->[0][$ch];
    }
   else
    {
     $x = $touni->[$ch][ord(substr($str,0,1,''))];
    }
   unless (defined $x)
    {
     last if $chk;
     # What do we do here ?
     $x = '';
    }
   $uni .= $x;
  }
 $_[1] = $str if $chk;
 return $uni;
}

sub fromUnicode
{
 my ($obj,$uni,$chk) = @_;
 my $fmuni = $obj->{'FmUni'};
 my $str   = '';
 my $def   = $obj->{'Def'};
 my $rep   = $obj->{'Rep'};
 while (length($uni))
  {
   my $ch = substr($uni,0,1,'');
   my $x  = $fmuni->{chr(ord($ch))};
   unless (defined $x)
    {
     last if ($chk);
     $x = $def;
    }
   $str .= pack(&$rep($x),$x);
  }
 $_[1] = $uni if $chk;
 return $str;
}

package Encode::iso10646_1;#

sub name { 'iso10646-1' }

sub toUnicode
{
 my ($obj,$str,$chk) = @_;
 my $uni   = '';
 while (length($str))
  {
   my $code = unpack('n',substr($str,0,2,'')) & 0xffff;
   $uni .= chr($code);
  }
 $_[1] = $str if $chk;
 return $uni;
}

sub fromUnicode
{
 my ($obj,$uni,$chk) = @_;
 my $str   = '';
 while (length($uni))
  {
   my $ch = substr($uni,0,1,'');
   my $x  = ord($ch);
   unless ($x < 32768)
    {
     last if ($chk);
     $x = 0;
    }
   $str .= pack('n',$x);
  }
 $_[1] = $uni if $chk;
 return $str;
}


package Encode::Escape;
use Carp;

sub read
{
 my ($class,$fh,$name) = @_;
 my %self = (Name => $name, Num => 0);
 while (<$fh>)
  {
   my ($key,$val) = /^(\S+)\s+(.*)$/;
   $val =~ s/^\{(.*?)\}/$1/g;
   $val =~ s/\\x([0-9a-f]{2})/chr(hex($1))/ge;
   $self{$key} = $val;
  }
 return bless \%self,$class;
}

sub name { shift->{'Name'} }

sub toUnicode
{
 croak("Not implemented yet");
}

sub fromUnicode
{
 croak("Not implemented yet");
}

1;

__END__
Commit	Line	Data
2c674647	1	package Encode;
	2
	3	$VERSION = 0.01;
	4
	5	require DynaLoader;
	6	require Exporter;
	7
	8	@ISA = qw(Exporter DynaLoader);
	9
	10	@EXPORT_OK =
	11	qw(
	12	bytes_to_utf8
	13	utf8_to_bytes
	14	chars_to_utf8
	15	utf8_to_chars
	16	utf8_to_chars_check
	17	bytes_to_chars
	18	chars_to_bytes
	19	from_to
	20	is_utf8
	21	on_utf8
	22	off_utf8
	23	utf_to_utf
656753f8	24	encodings
2c674647	25	);
	26
	27	bootstrap Encode ();
	28
	29	=pod
	30
	31	=head1 NAME
	32
	33	Encode - character encodings
	34
	35	=head2 TERMINOLOGY
	36
	37	=over
	38
	39	=item *
	40
	41	I<char>: a character in the range 0..maxint (at least 2**32-1)
	42
	43	=item *
	44
	45	I<byte>: a character in the range 0..255
	46
	47	=back
	48
	49	The marker [INTERNAL] marks Internal Implementation Details, in
	50	general meant only for those who think they know what they are doing,
	51	and such details may change in future releases.
	52
	53	=head2 bytes
	54
	55	=over 4
	56
	57	=item *
	58
	59	bytes_to_utf8(STRING [, FROM])
	60
	61	The bytes in STRING are recoded in-place into UTF-8. If no FROM is
	62	specified the bytes are expected to be encoded in US-ASCII or ISO
	63	8859-1 (Latin 1). Returns the new size of STRING, or C<undef> if
	64	there's a failure.
	65
656753f8	66	[INTERNAL] Also the UTF-8 flag of STRING is turned on.
2c674647	67
	68	=item *
	69
	70	utf8_to_bytes(STRING [, TO [, CHECK]])
	71
	72	The UTF-8 in STRING is decoded in-place into bytes. If no TO encoding
	73	is specified the bytes are expected to be encoded in US-ASCII or ISO
	74	8859-1 (Latin 1). Returns the new size of STRING, or C<undef> if
	75	there's a failure.
	76
	77	What if there are characters > 255? What if the UTF-8 in STRING is
	78	malformed? See L</"Handling Malformed Data">.
	79
	80	[INTERNAL] The UTF-8 flag of STRING is not checked.
	81
	82	=back
	83
	84	=head2 chars
	85
	86	=over 4
	87
	88	=item *
	89
	90	chars_to_utf8(STRING)
	91
	92	The chars in STRING are encoded in-place into UTF-8. Returns the new
	93	size of STRING, or C<undef> if there's a failure.
	94
	95	No assumptions are made on the encoding of the chars. If you want to
	96	assume that the chars are Unicode and to trap illegal Unicode
	97	characters, you must use C<from_to('Unicode', ...)>.
	98
	99	[INTERNAL] Also the UTF-8 flag of STRING is turned on.
	100
	101	=over 4
	102
	103	=item *
	104
	105	utf8_to_chars(STRING)
	106
	107	The UTF-8 in STRING is decoded in-place into chars. Returns the new
656753f8	108	size of STRING, or C<undef> if there's a failure.
2c674647	109
	110	If the UTF-8 in STRING is malformed C<undef> is returned, and also an
	111	optional lexical warning (category utf8) is given.
	112
	113	[INTERNAL] The UTF-8 flag of STRING is not checked.
	114
	115	=item *
	116
	117	utf8_to_chars_check(STRING [, CHECK])
	118
	119	(Note that special naming of this interface since a two-argument
	120	utf8_to_chars() has different semantics.)
	121
	122	The UTF-8 in STRING is decoded in-place into chars. Returns the new
	123	size of STRING, or C<undef> if there is a failure.
	124
	125	If the UTF-8 in STRING is malformed? See L</"Handling Malformed Data">.
	126
	127	[INTERNAL] The UTF-8 flag of STRING is not checked.
	128
	129	=back
	130
	131	=head2 chars With Encoding
	132
	133	=over 4
	134
	135	=item *
	136
	137	chars_to_utf8(STRING, FROM [, CHECK])
	138
	139	The chars in STRING encoded in FROM are recoded in-place into UTF-8.
	140	Returns the new size of STRING, or C<undef> if there's a failure.
	141
	142	No assumptions are made on the encoding of the chars. If you want to
	143	assume that the chars are Unicode and to trap illegal Unicode
	144	characters, you must use C<from_to('Unicode', ...)>.
	145
	146	[INTERNAL] Also the UTF-8 flag of STRING is turned on.
	147
	148	=item *
	149
	150	utf8_to_chars(STRING, TO [, CHECK])
	151
	152	The UTF-8 in STRING is decoded in-place into chars encoded in TO.
	153	Returns the new size of STRING, or C<undef> if there's a failure.
	154
	155	If the UTF-8 in STRING is malformed? See L</"Handling Malformed Data">.
	156
	157	[INTERNAL] The UTF-8 flag of STRING is not checked.
	158
	159	=item *
	160
	161	bytes_to_chars(STRING, FROM [, CHECK])
	162
	163	The bytes in STRING encoded in FROM are recoded in-place into chars.
	164	Returns the new size of STRING in bytes, or C<undef> if there's a
	165	failure.
	166
	167	If the mapping is impossible? See L</"Handling Malformed Data">.
	168
	169	=item *
	170
	171	chars_to_bytes(STRING, TO [, CHECK])
	172
173	The chars in STRING are recoded in-place to bytes encoded in TO.
174	Returns the new size of STRING in bytes, or C<undef> if there's a
175	failure.
176
177	If the mapping is impossible? See L</"Handling Malformed Data">.
178
179	=item *
180
181	from_to(STRING, FROM, TO [, CHECK])
182
183	The chars in STRING encoded in FROM are recoded in-place into TO.
184	Returns the new size of STRING, or C<undef> if there's a failure.
185
186	If mapping between the encodings is impossible?
187	See L</"Handling Malformed Data">.
188
189	[INTERNAL] If TO is UTF-8, also the UTF-8 flag of STRING is turned on.
190
191	=back
192
193	=head2 Testing For UTF-8
194
195	=over 4
196
197	=item *
198
199	is_utf8(STRING [, CHECK])
200
201	[INTERNAL] Test whether the UTF-8 flag is turned on in the STRING.
202	If CHECK is true, also checks the data in STRING for being
203	well-formed UTF-8. Returns true if successful, false otherwise.
204
205	=back
206
207	=head2 Toggling UTF-8-ness
208
209	=over 4
210
211	=item *
212
213	on_utf8(STRING)
214
215	[INTERNAL] Turn on the UTF-8 flag in STRING. The data in STRING is
216	B<not> checked for being well-formed UTF-8. Do not use unless you
217	B<know> that the STRING is well-formed UTF-8. Returns the previous
218	state of the UTF-8 flag (so please don't test the return value as
219	I<not> success or failure), or C<undef> if STRING is not a string.
220
221	=item *
222
223	off_utf8(STRING)
224
225	[INTERNAL] Turn off the UTF-8 flag in STRING. Do not use frivolously.
226	Returns the previous state of the UTF-8 flag (so please don't test the
227	return value as I<not> success or failure), or C<undef> if STRING is
228	not a string.
229
230	=back
231
232	=head2 UTF-16 and UTF-32 Encodings
233
234	=over 4
235
236	=item *
237
238	utf_to_utf(STRING, FROM, TO [, CHECK])
239
240	The data in STRING is converted from Unicode Transfer Encoding FROM to
241	Unicode Transfer Encoding TO. Both FROM and TO may be any of the
242	following tags (case-insensitive, with or without 'utf' or 'utf-' prefix):
243
244	tag meaning
245
246	'7' UTF-7
247	'8' UTF-8
248	'16be' UTF-16 big-endian
249	'16le' UTF-16 little-endian
250	'16' UTF-16 native-endian
251	'32be' UTF-32 big-endian
252	'32le' UTF-32 little-endian
253	'32' UTF-32 native-endian
254
255	UTF-16 is also known as UCS-2, 16 bit or 2-byte chunks, and UTF-32 as
256	UCS-4, 32-bit or 4-byte chunks. Returns the new size of STRING, or
257	C<undef> is there's a failure.
258
259	If FROM is UTF-8 and the UTF-8 in STRING is malformed? See
260	L</"Handling Malformed Data">.
261
262	[INTERNAL] Even if CHECK is true and FROM is UTF-8, the UTF-8 flag of
263	STRING is not checked. If TO is UTF-8, also the UTF-8 flag of STRING is
264	turned on. Identical FROM and TO are fine.
265
266	=back
267
268	=head2 Handling Malformed Data
269
270	If CHECK is not set, C<undef> is returned. If the data is supposed to
271	be UTF-8, an optional lexical warning (category utf8) is given. If
272	CHECK is true but not a code reference, dies. If CHECK is a code
273	reference, it is called with the arguments
274
275	(MALFORMED_STRING, STRING_FROM_SO_FAR, STRING_TO_SO_FAR)
276
277	Two return values are expected from the call: the string to be used in
278	the result string in place of the malformed section, and the length of
279	the malformed section in bytes.
280
281	=cut
282
283	sub bytes_to_utf8 {
284	&_bytes_to_utf8;
285	}
286
287	sub utf8_to_bytes {
288	&_utf8_to_bytes;
289	}
290
291	sub chars_to_utf8 {
292	&C_to_utf8;
293	}
294
295	sub utf8_to_chars {
296	&_utf8_to_chars;
297	}
298
299	sub utf8_to_chars_check {
300	&_utf8_to_chars_check;
301	}
302
303	sub bytes_to_chars {
304	&_bytes_to_chars;
305	}
306
307	sub chars_to_bytes {
308	&_chars_to_bytes;
309	}
310
2c674647	311	sub is_utf8 {
	312	&_is_utf8;
	313	}
	314
	315	sub on_utf8 {
	316	&_on_utf8;
	317	}
	318
	319	sub off_utf8 {
	320	&_off_utf8;
	321	}
	322
	323	sub utf_to_utf {
	324	&_utf_to_utf;
	325	}
	326
bf230f3d	327	use Carp;
bf230f3d	328
656753f8	329	sub from_to
	330	{
	331	my ($string,$from,$to,$check) = @_;
	332	my $f = __PACKAGE__->getEncoding($from);
bf230f3d	333	croak("Unknown encoding '$from'") unless $f;
656753f8	334	my $t = __PACKAGE__->getEncoding($to);
bf230f3d	335	croak("Unknown encoding '$to'") unless $t;
656753f8	336	my $uni = $f->toUnicode($string,$check);
bf230f3d	337	return undef if ($check && length($string));
656753f8	338	$string = $t->fromUnicode($uni,$check);
bf230f3d	339	return undef if ($check && length($uni));
656753f8	340	return length($_[0] = $string);
	341	}
	342
2f2b4ff2	343	# The global hash is declared in XS code
	344	$encoding{Unicode} = bless({},'Encode::Unicode');
	345	$encoding{iso10646-1} = bless({},'Encode::iso10646_1');
5345d506	346
656753f8	347	sub encodings
	348	{
	349	my ($class) = @_;
5345d506	350	foreach my $dir (@INC)
656753f8	351	{
5345d506	352	if (opendir(my $dh,"$dir/Encode"))
656753f8	353	{
5345d506	354	while (defined(my $name = readdir($dh)))
	355	{
	356	if ($name =~ /^(.*)\.enc$/)
	357	{
	358	next if exists $encoding{$1};
	359	$encoding{$1} = "$dir/$name";
	360	}
	361	}
	362	closedir($dh);
656753f8	363	}
5345d506	364	}
	365	return keys %encoding;
	366	}
	367
	368	sub loadEncoding
	369	{
	370	my ($class,$name,$file) = @_;
	371	if (open(my $fh,$file))
	372	{
	373	my $type;
	374	while (1)
	375	{
	376	my $line = <$fh>;
	377	$type = substr($line,0,1);
	378	last unless $type eq '#';
	379	}
	380	$class .= ('::'.(($type eq 'E') ? 'Escape' : 'Table'));
2f2b4ff2	381	warn "Loading $file";
5345d506	382	return $class->read($fh,$name,$type);
656753f8	383	}
	384	else
	385	{
5345d506	386	return undef;
656753f8	387	}
656753f8	388	}
656753f8	389
656753f8	390	sub getEncoding
	391	{
	392	my ($class,$name) = @_;
5345d506	393	my $enc;
5345d506	394	unless (ref($enc = $encoding{$name}))
656753f8	395	{
5345d506	396	$enc = $class->loadEncoding($name,$enc) if defined $enc;
5345d506	397	unless (ref($enc))
656753f8	398	{
5345d506	399	foreach my $dir (@INC)
656753f8	400	{
5345d506	401	last if ($enc = $class->loadEncoding($name,"$dir/Encode/$name.enc"));
656753f8	402	}
87714904	403	}
5345d506	404	$encoding{$name} = $enc;
656753f8	405	}
5345d506	406	return $enc;
656753f8	407	}
	408
	409	package Encode::Unicode;
	410
	411	# Dummy package that provides the encode interface
	412
	413	sub name { 'Unicode' }
	414
	415	sub toUnicode { $_[1] }
	416
	417	sub fromUnicode { $_[1] }
	418
	419	package Encode::Table;
	420
	421	sub read
	422	{
	423	my ($class,$fh,$name,$type) = @_;
	424	my $rep = $class->can("rep_$type");
	425	my ($def,$sym,$pages) = split(/\s+/,scalar(<$fh>));
	426	my @touni;
	427	my %fmuni;
	428	my $count = 0;
	429	$def = hex($def);
656753f8	430	while ($pages--)
656753f8	431	{
87714904	432	my $line = <$fh>;
	433	chomp($line);
	434	my $page = hex($line);
656753f8	435	my @page;
	436	my $ch = $page * 256;
	437	for (my $i = 0; $i < 16; $i++)
	438	{
	439	my $line = <$fh>;
	440	for (my $j = 0; $j < 16; $j++)
	441	{
	442	my $val = hex(substr($line,0,4,''));
	443	if ($val \|\| !$ch)
	444	{
	445	my $uch = chr($val);
	446	push(@page,$uch);
87714904	447	$fmuni{$uch} = $ch;
656753f8	448	$count++;
	449	}
	450	else
	451	{
	452	push(@page,undef);
	453	}
	454	$ch++;
	455	}
	456	}
	457	$touni[$page] = \@page;
	458	}
	459
	460	return bless {Name => $name,
	461	Rep => $rep,
	462	ToUni => \@touni,
	463	FmUni => \%fmuni,
	464	Def => $def,
	465	Num => $count,
	466	},$class;
	467	}
	468
	469	sub name { shift->{'Name'} }
	470
	471	sub rep_S { 'C' }
	472
5dcbab34	473	sub rep_D { 'n' }
656753f8	474
5dcbab34	475	sub rep_M { ($_[0] > 255) ? 'n' : 'C' }
656753f8	476
	477	sub representation
	478	{
	479	my ($obj,$ch) = @_;
	480	$ch = 0 unless @_ > 1;
	481	$obj-{'Rep'}->($ch);
	482	}
	483
	484	sub toUnicode
	485	{
bf230f3d	486	my ($obj,$str,$chk) = @_;
656753f8	487	my $rep = $obj->{'Rep'};
	488	my $touni = $obj->{'ToUni'};
	489	my $uni = '';
	490	while (length($str))
	491	{
	492	my $ch = ord(substr($str,0,1,''));
bf230f3d	493	my $x;
656753f8	494	if (&$rep($ch) eq 'C')
656753f8	495	{
bf230f3d	496	$x = $touni->[0][$ch];
656753f8	497	}
	498	else
	499	{
bf230f3d	500	$x = $touni->[$ch][ord(substr($str,0,1,''))];
656753f8	501	}
bf230f3d	502	unless (defined $x)
	503	{
	504	last if $chk;
	505	# What do we do here ?
	506	$x = '';
	507	}
	508	$uni .= $x;
656753f8	509	}
bf230f3d	510	$_[1] = $str if $chk;
656753f8	511	return $uni;
	512	}
	513
	514	sub fromUnicode
	515	{
bf230f3d	516	my ($obj,$uni,$chk) = @_;
656753f8	517	my $fmuni = $obj->{'FmUni'};
	518	my $str = '';
	519	my $def = $obj->{'Def'};
87714904	520	my $rep = $obj->{'Rep'};
656753f8	521	while (length($uni))
	522	{
	523	my $ch = substr($uni,0,1,'');
63eec5db	524	my $x = $fmuni->{chr(ord($ch))};
bf230f3d	525	unless (defined $x)
	526	{
	527	last if ($chk);
	528	$x = $def;
	529	}
87714904	530	$str .= pack(&$rep($x),$x);
	531	}
	532	$_[1] = $uni if $chk;
	533	return $str;
	534	}
	535
	536	package Encode::iso10646_1;#
	537
	538	sub name { 'iso10646-1' }
	539
	540	sub toUnicode
	541	{
	542	my ($obj,$str,$chk) = @_;
	543	my $uni = '';
	544	while (length($str))
	545	{
5dcbab34	546	my $code = unpack('n',substr($str,0,2,'')) & 0xffff;
87714904	547	$uni .= chr($code);
	548	}
	549	$_[1] = $str if $chk;
	550	return $uni;
	551	}
	552
	553	sub fromUnicode
	554	{
	555	my ($obj,$uni,$chk) = @_;
	556	my $str = '';
	557	while (length($uni))
	558	{
	559	my $ch = substr($uni,0,1,'');
	560	my $x = ord($ch);
	561	unless ($x < 32768)
	562	{
	563	last if ($chk);
	564	$x = 0;
	565	}
5dcbab34	566	$str .= pack('n',$x);
656753f8	567	}
bf230f3d	568	$_[1] = $uni if $chk;
656753f8	569	return $str;
	570	}
	571
2f2b4ff2	572
656753f8	573	package Encode::Escape;
	574	use Carp;
	575
	576	sub read
	577	{
	578	my ($class,$fh,$name) = @_;
	579	my %self = (Name => $name, Num => 0);
	580	while (<$fh>)
	581	{
	582	my ($key,$val) = /^(\S+)\s+(.*)$/;
	583	$val =~ s/^\{(.*?)\}/$1/g;
	584	$val =~ s/\\x([0-9a-f]{2})/chr(hex($1))/ge;
	585	$self{$key} = $val;
	586	}
	587	return bless \%self,$class;
	588	}
	589
	590	sub name { shift->{'Name'} }
	591
	592	sub toUnicode
	593	{
	594	croak("Not implemented yet");
	595	}
	596
	597	sub fromUnicode
	598	{
	599	croak("Not implemented yet");
	600	}
	601
	602	1;
	603
	604	__END__