require 5.004;

use ExtUtils::MakeMaker;

use Config qw(%Config);

for (@ARGV) {

  /^-pm/ and $no_xs = 1;

  /^-xs/ and $no_xs = 0;

}

sub init {

  my $hash = $_[1];

  if ($no_xs) {

    @{$hash}{XS,C} = ( {}, [] );

  }

  $hash;

}

sub write_makefile {

  WriteMakefile(

    NAME         => 'Digest::CRC',

    VERSION_FROM => 'lib/Digest/CRC.pm', # finds $VERSION

    PL_FILES     => {},

    CONFIGURE    => \&init,

    clean        => {FILES => 'test.c typemap'}

  );

}

sub no_cc {

  $no_xs = 1;

  print <<"EDQ";

 I cannot determine if you have a C compiler

 so I will install a perl-only implementation

 You can force installation of the XS version with

    perl Makefile.PL -xs

EDQ

  write_makefile();

  exit;

}

if ($] < 5.006001) {

  open(TYPEMAP,">typemap");

  print TYPEMAP <<'EOS';

NV                      T_NV

UV                      T_UV

INPUT

T_NV

	$var = ($type)SvNV($arg)

T_UV

	$var = ($type)SvUV($arg)

OUTPUT

T_NV

	sv_setnv($arg, (NV)$var);

T_UV

	sv_setuv($arg, (UV)$var);

EOS

  close(TYPEMAP);

}

write_makefile();

exit if defined $no_xs;

print "Testing if you have a C compiler\n";

open(F,">test.c") or no_cc();

print F <

int main() { return 0; }

EOF

close(F) or no_cc();

$make = $Config{make} || 'make';

system("$make test$Config{obj_ext}") and no_cc();