#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include <gmp.h>

MODULE = Math::Tohex  PACKAGE = Math::Tohex

SV *
tohex(num)
        char *num
    CODE:
        char *out;
        ST(0) = sv_newmortal();
        mpz_t big;
        mpz_init_set_str(big, num, 10);
        Newx(out, 4 + mpz_sizeinbase(big, 16), char);
        mpz_get_str(out, 16, big);
        sv_setpv(ST(0), out);
        mpz_clear(big);
        Safefree(out);


##</code><code>##

package Math::Tohex;

require Exporter;
require DynaLoader;
our $VERSION = "1.00";
our @ISA = (Exporter::, DynaLoader::);
our @EXPORT = "tohex";

bootstrap Math::Tohex::;

1;
__END__

##</code><code>##

use ExtUtils::MakeMaker;

WriteMakefile(
    NAME => "Math::Tohex",
    VERSION_FROM => "lib/Math/Tohex.pm",
    LIBS => ["-lgmp"],
);

##</code><code>##

perl Makefile.PL && make

##</code><code>##

perl -wE 'use Math::BigInt; say Math::BigInt->new("4335043554366887798866555766")->as_hex;'