> hello,
>   recently i downloaded postgresql-7.3b5,i found the conversion between
> gb18030 and utf was mistake  because the map file bwteen them wasn't
> obviously right.the first byte of utf8 encoding  with two bytes shoule
> between 0xc0 with 0xfd,the map file didn't accord with this condition
> .please check it ,i wished that postgresql-7.3 can support the GB18030 and
> can run in China.
>                                       best regards
>                                                         jenny wang

Thanks for testing GB18030 support. Yes, the map file is completely
broken. I have attached fixed map generation perl script. Please test
it (I do not understand Chinese).

(1) save the perl script in the postgresql-7.3b5 source tree as:
    src/backend/utils/mb/Unicode/UCS_to_GB18030.pl.

(2) run it.

    cd src/backend/utils/mb/Unicode
    ./UCS_to_GB18030.pl

(3) the script will generate
    src/backend/utils/mb/Unicode/utf8_to_gb18030.map
    and
    src/backend/utils/mb/Unicode/gb18030_to_utf8.map

(4) If they look good, rebuild PostgreSQL and test it.
--
Tatsuo Ishii

#! /usr/bin/perl
#
# Copyright 2002 by Bill Huang
#
# $Id: UCS_to_GB18030.pl,v 1.1 2002/06/13 08:28:55 ishii Exp $
#
# Generate UTF-8 <--> GB18030 code conversion tables from
# map files provided by Unicode organization.
# Unfortunately it is prohibited by the organization
# to distribute the map files. So if you try to use this script,
# you have to obtain ISO10646-GB18030.TXT from 
# the organization's ftp site.
#
# ISO10646-GB18030.TXT format:
#		 GB18030 code in hex
#		 UCS-2 code in hex
#		 # and Unicode name (not used in this script)

require "ucs2utf.pl";

# first generate UTF-8 --> GB18030 table

$in_file = "ISO10646-GB18030.TXT";

open( FILE, $in_file ) || die( "cannot open $in_file" );

while( <FILE> ){
	chop;
	if( /^#/ ){
		next;
	}
	( $u, $c, $rest ) = split;
	$ucs = hex($u);
	$code = hex($c);
	if( $code >= 0x80 && $ucs >= 0x0080 ){
		$utf = &ucs2utf($ucs);
		if( $array{ $utf } ne "" ){
			printf STDERR "Warning: duplicate unicode: %04x\n",$ucs;
			next;
		}
		$count++;

		$array{ $utf } = $code;
	}
}
close( FILE );

#
# first, generate UTF8 --> GB18030 table
#

$file = "utf8_to_gb18030.map";
open( FILE, "> $file" ) || die( "cannot open $file" );
print FILE "static pg_utf_to_local ULmapGB18030[ $count ] = {\n";

for $index ( sort {$a <=> $b} keys( %array ) ){
	$code = $array{ $index };
	$count--;
	if( $count == 0 ){
		printf FILE "  {0x%04x, 0x%04x}\n", $index, $code;
	} else {
		printf FILE "  {0x%04x, 0x%04x},\n", $index, $code;
	}
}

print FILE "};\n";
close(FILE);

#
# then generate GB18030 --> UTF8 table
#
reset 'array';

open( FILE, $in_file ) || die( "cannot open $in_file" );

while( <FILE> ){
	chop;
	if( /^#/ ){
		next;
	}
	( $c, $u, $rest ) = split;
	$ucs = hex($u);
	$code = hex($c);
	if( $code >= 0x80 && $ucs >= 0x0080 ){
		$utf = &ucs2utf($ucs);
		if( $array{ $code } ne "" ){
			printf STDERR "Warning: duplicate code: %04x\n",$ucs;
			next;
		}
		$count++;

		$array{ $code } = $utf;
	}
}
close( FILE );

$file = "gb18030_to_utf8.map";
open( FILE, "> $file" ) || die( "cannot open $file" );
print FILE "static pg_local_to_utf LUmapGB18030[ $count ] = {\n";
for $index ( sort {$a <=> $b} keys( %array ) ){
	$utf = $array{ $index };
	$count--;
	if( $count == 0 ){
		printf FILE "  {0x%04x, 0x%04x}\n", $index, $utf;
	} else {
		printf FILE "  {0x%04x, 0x%04x},\n", $index, $utf;
	}
}

print FILE "};\n";
close(FILE);
Tue, 12 Nov 2002 13:39:41 +0900 (JST)
Tatsuo Ishii <t-ishii@sra.co.jp>
Re: the map file between gb18030 and utf8 is error