libcryptx-perl/lib/Math/BigInt/LTM.pm

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2018-03-22 15:51:09 +01:00
package Math::BigInt::LTM;
use strict;
use warnings;
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our $VERSION = '0.058_002';
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use CryptX;
sub api_version() { 2 }
sub CLONE_SKIP { 1 } # prevent cloning
### same as overloading in Math::BigInt::Lib
use overload
# overload key: with_assign
'+' => sub {
my $class = ref $_[0];
my $x = $class -> _copy($_[0]);
my $y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
return $class -> _add($x, $y);
},
'-' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _sub($x, $y);
},
'*' => sub {
my $class = ref $_[0];
my $x = $class -> _copy($_[0]);
my $y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
return $class -> _mul($x, $y);
},
'/' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _div($x, $y);
},
'%' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _mod($x, $y);
},
'**' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _pow($x, $y);
},
'<<' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $class -> _num($_[0]);
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $_[0];
$y = ref($_[1]) ? $class -> _num($_[1]) : $_[1];
}
return $class -> _blsft($x, $y);
},
'>>' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _brsft($x, $y);
},
# overload key: num_comparison
'<' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _acmp($x, $y) < 0;
},
'<=' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _acmp($x, $y) <= 0;
},
'>' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _acmp($x, $y) > 0;
},
'>=' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _acmp($x, $y) >= 0;
},
'==' => sub {
my $class = ref $_[0];
my $x = $class -> _copy($_[0]);
my $y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
return $class -> _acmp($x, $y) == 0;
},
'!=' => sub {
my $class = ref $_[0];
my $x = $class -> _copy($_[0]);
my $y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
return $class -> _acmp($x, $y) != 0;
},
# overload key: 3way_comparison
'<=>' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _acmp($x, $y);
},
# overload key: binary
'&' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _and($x, $y);
},
'|' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _or($x, $y);
},
'^' => sub {
my $class = ref $_[0];
my ($x, $y);
if ($_[2]) { # if swapped
$y = $_[0];
$x = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
} else {
$x = $class -> _copy($_[0]);
$y = ref($_[1]) ? $_[1] : $class -> _new($_[1]);
}
return $class -> _xor($x, $y);
},
# overload key: func
'abs' => sub { $_[0] },
'sqrt' => sub {
my $class = ref $_[0];
return $class -> _sqrt($class -> _copy($_[0]));
},
'int' => sub { $_[0] -> copy() -> bint(); },
# overload key: conversion
'bool' => sub { ref($_[0]) -> _is_zero($_[0]) ? '' : 1; },
'""' => sub { ref($_[0]) -> _str($_[0]); },
'0+' => sub { ref($_[0]) -> _num($_[0]); },
'=' => sub { ref($_[0]) -> _copy($_[0]); },
;
### same as import() in Math::BigInt::Lib
sub import { }
### same as _check() in Math::BigInt::Lib
sub _check {
# used by the test suite
my ($class, $x) = @_;
return "Input is undefined" unless defined $x;
return "$x is not a reference" unless ref($x);
return 0;
}
### same as _digit() in Math::BigInt::Lib
sub _digit {
my ($class, $x, $n) = @_;
substr($class ->_str($x), -($n+1), 1);
}
### same as _num() in Math::BigInt::Lib
sub _num {
my ($class, $x) = @_;
0 + $class -> _str($x);
}
### BEWARE!!! NOT THE SAME as _fac() in Math::BigInt::Lib
sub _fac {
# factorial
my ($class, $x) = @_;
my $two = $class -> _two();
if ($class -> _acmp($x, $two) < 0) {
$class->_set($x, 1);
return $x;
}
my $i = $class -> _copy($x);
while ($class -> _acmp($i, $two) > 0) {
$i = $class -> _dec($i);
$x = $class -> _mul($x, $i);
}
return $x;
}
### same as _nok() in Math::BigInt::Lib
sub _nok {
# Return binomial coefficient (n over k).
# Given refs to arrays, return ref to array.
# First input argument is modified.
my ($class, $n, $k) = @_;
# If k > n/2, or, equivalently, 2*k > n, compute nok(n, k) as
# nok(n, n-k), to minimize the number if iterations in the loop.
{
my $twok = $class -> _mul($class -> _two(), $class -> _copy($k));
if ($class -> _acmp($twok, $n) > 0) {
$k = $class -> _sub($class -> _copy($n), $k);
}
}
# Example:
#
# / 7 \ 7! 1*2*3*4 * 5*6*7 5 * 6 * 7 6 7
# | | = --------- = --------------- = --------- = 5 * - * -
# \ 3 / (7-3)! 3! 1*2*3*4 * 1*2*3 1 * 2 * 3 2 3
if ($class -> _is_zero($k)) {
return $class -> _one();
}
# Make a copy of the original n, since we'll be modifying n in-place.
my $n_orig = $class -> _copy($n);
# n = 5, f = 6, d = 2 (cf. example above)
$n = $class -> _sub($n, $k);
$n = $class -> _inc($n);
my $f = $class -> _copy($n);
$class -> _inc($f);
my $d = $class -> _two();
# while f <= n (the original n, that is) ...
while ($class -> _acmp($f, $n_orig) <= 0) {
# n = (n * f / d) == 5 * 6 / 2 (cf. example above)
$n = $class -> _mul($n, $f);
$n = $class -> _div($n, $d);
# f = 7, d = 3 (cf. example above)
$f = $class -> _inc($f);
$d = $class -> _inc($d);
}
return $n;
}
### same as _log_int() in Math::BigInt::Lib
sub _log_int {
# calculate integer log of $x to base $base
# ref to array, ref to array - return ref to array
my ($class, $x, $base) = @_;
# X == 0 => NaN
return if $class -> _is_zero($x);
$base = $class -> _new(2) unless defined($base);
$base = $class -> _new($base) unless ref($base);
# BASE 0 or 1 => NaN
return if $class -> _is_zero($base) || $class -> _is_one($base);
# X == 1 => 0 (is exact)
if ($class -> _is_one($x)) {
return $class -> _zero(), 1;
}
my $cmp = $class -> _acmp($x, $base);
# X == BASE => 1 (is exact)
if ($cmp == 0) {
return $class -> _one(), 1;
}
# 1 < X < BASE => 0 (is truncated)
if ($cmp < 0) {
return $class -> _zero(), 0;
}
my $y;
# log(x) / log(b) = log(xm * 10^xe) / log(bm * 10^be)
# = (log(xm) + xe*(log(10))) / (log(bm) + be*log(10))
{
my $x_str = $class -> _str($x);
my $b_str = $class -> _str($base);
my $xm = "." . $x_str;
my $bm = "." . $b_str;
my $xe = length($x_str);
my $be = length($b_str);
my $log10 = log(10);
my $guess = int((log($xm) + $xe * $log10) / (log($bm) + $be * $log10));
$y = $class -> _new($guess);
}
my $trial = $class -> _pow($class -> _copy($base), $y);
my $acmp = $class -> _acmp($trial, $x);
# Did we get the exact result?
return $y, 1 if $acmp == 0;
# Too small?
while ($acmp < 0) {
$trial = $class -> _mul($trial, $base);
$y = $class -> _inc($y);
$acmp = $class -> _acmp($trial, $x);
}
# Too big?
while ($acmp > 0) {
$trial = $class -> _div($trial, $base);
$y = $class -> _dec($y);
$acmp = $class -> _acmp($trial, $x);
}
return $y, 1 if $acmp == 0; # result is exact
return $y, 0; # result is too small
}
1;
=pod
=head1 NAME
Math::BigInt::LTM - Use the libtommath library for Math::BigInt routines
=head1 SYNOPSIS
use Math::BigInt lib => 'LTM';
## See Math::BigInt docs for usage.
=head1 DESCRIPTION
Provides support for big integer calculations by means of the libtommath c-library.
I<Since: CryptX-0.029>
=head1 SEE ALSO
L<Math::BigInt>, L<https://github.com/libtom/libtommath>
=cut