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use ExtUtils::MakeMaker;
use Config;
use Cwd;
use 5.006;

require DynaLoader;

$geoip_libpath = '';
$geoip_incpath = '';

my @replacement_args;

my %config;

while ( $_ = shift ) {
  my ( $key, $val ) = split( /=/, $_, 2 );
  $config{$key} = $val;
}

unless ( $config{LIBS} ) {
  # currently we check only for the C Library version if it is in a 
  # standard place
  my $geoip_version = 0;
  my $clib          = DynaLoader::dl_findfile('GeoIP');
  my $found         = $clib ? 1 : 0;
  if ($clib) {
    $geoip_version = 10000;    # V 1.0.0 ( means, we have something )

    # a GeoIP lib is found, just check the version, we need 1.4.5 now
    my $lib = DynaLoader::dl_load_file( $clib, 0 );
    if ($lib) {
      for (
            [ 10403, 'GeoIP_last_netmask' ],    # V 1.4.3
            [ 10405, 'GeoIP_range_by_ip' ],     # V 1.4.5
            [ 10405, 'GeoIP_code_by_id' ],      # V 1.4.5
        ) {
        $geoip_version = $_->[0] if DynaLoader::dl_find_symbol( $lib, $_->[1] );
      }

      #
      if ( $geoip_version < 10405 ) {
        print STDERR <<__ERR__;
Your installed version of libgeoip is outdated! Please update to at least
version to 1.4.5 and reinstall this module.

http://www.maxmind.com/app/c

__ERR__
        exit(0);
      }
    }
  }

=pod

  # Test for existence of libGeoIP
  my $found = 0;
  foreach (split(/\s+/, $Config{libpth})) {
    if (-f "$_/libGeoIP." . $Config{so}) {
      $found = 1;
      last;
    }
  }

=cut

  if (!$found and !$config{PP}) {
    print STDERR <<'GeoIP_Not_Installed;';

The GeoIP CAPI is not installed you should do that. Otherwise try 

    perl Makefile.PL PP=1
    
to install this module anyway. It uses a slower pure perl version 
and you can rebuid it later.

GeoIP must be installed prior to building Geo::IP and I can't find
it in the standard library directories. You can download GeoIP C API from:

http://www.maxmind.com/app/c

If GeoIP is installed, but in a non-standard directory, then use the
following options to Makefile.PL:

    perl Makefile.PL LIBS='-L/home/me/lib' INC='-I/home/me/include'

Note that if you build against a shareable library in a non-standard location
you may (on some platforms) also have to set your LD_LIBRARY_PATH environment
variable at run time for perl to find the library.

If you installed the GeoIP C libraries to the /usr/local/lib directory,
then you may need to add /usr/local/lib to /etc/ld.so.conf then run
/sbin/ldconfig /etc/ld.so.conf

GeoIP_Not_Installed;
    exit 0;    # make cpantesters happy
  }
}

if ( $config{LIBS} !~ /\-lGeoIP\b/ ) {
  $config{LIBS} .= ' -lGeoIP';
}

@extras = ();

push( @extras, CAPI => 'TRUE' )
  if (     $PERL_VERSION >= 5.005
       and $OSNAME eq 'MSWin32'
       and $Config{archname} =~ /-object\b/i );

push(
      @extras,
      ABSTRACT_FROM => 'lib/Geo/IP.pm',
      AUTHOR        => 'T.J. Mather (tjmather@tjmather.com)'
) if ( $ExtUtils::MakeMaker::Version >= 5.4301 );

my $pp = delete $config{PP};

WriteMakefile(
  NAME         => 'Geo::IP',
  dist         => { COMPRESS => 'gzip', SUFFIX => '.gz' },
  VERSION_FROM => 'lib/Geo/IP.pm',
  LIBS => $pp ? [] : ['-lGeoIP'],
  DEFINE => '-DPERL_EXT',    # otherwise 'cxinc' isn't defined

  CONFIGURE => sub { @{ $_[1] }{qw/XS C/} = ( {}, [] ) if $pp; $_[1] },
  @extras,
  %config
);