openssl/test/recipes/bc.pl
Richard Levitte f3356b7f49 Add math tests recipes
The math recipes are among the heavier, but also quite important.
For the BN test, we have previously relied on bc to verify the numbers.
Unfortunately, bc doesn't exist everywhere, making tests on some platforms
rather painful.  With the new recipe (recipes/10-test_bn.t), we rely
on perl's Math::BigInt and a homegrown simple calculator (recipes/bc.pl)
that can do enough to cover for bc.

Reviewed-by: Rich Salz <rsalz@openssl.org>
2015-09-07 16:10:57 +02:00

97 lines
2.3 KiB
Perl

#! /usr/bin/perl
use strict;
use warnings;
use Math::BigInt;
sub calc {
@_ = __adder(@_);
if (scalar @_ != 1) { return "NaN"; }
return shift;
}
sub __canonhex {
my ($sign, $hex) = (shift =~ /^([+\-]?)(.*)$/);
$hex = "0x".$hex if $hex !~ /^0x/;
return $sign.$hex;
}
sub __adder {
@_ = __multiplier(@_);
while (scalar @_ > 1 && $_[1] =~ /^[\+\-]$/) {
my $operand1 = Math::BigInt->from_hex(__canonhex(shift));
my $operator = shift;
@_ = __multiplier(@_);
my $operand2 = Math::BigInt->from_hex(__canonhex(shift));
if ($operator eq "+") {
$operand1->badd($operand2);
} elsif ($operator eq "-") {
$operand1->bsub($operand2);
} else {
die "SOMETHING WENT AWFULLY WRONG";
}
unshift @_, $operand1->as_hex();
}
return @_;
}
sub __multiplier {
@_ = __power(@_);
while (scalar @_ > 1 && $_[1] =~ /^[\*\/%]$/) {
my $operand1 = Math::BigInt->from_hex(__canonhex(shift));
my $operator = shift;
@_ = __power(@_);
my $operand2 = Math::BigInt->from_hex(__canonhex(shift));
if ($operator eq "*") {
$operand1->bmul($operand2);
} elsif ($operator eq "/") {
$operand1->bdiv($operand2);
} elsif ($operator eq "%") {
# Here's a bit of a quirk...
# With OpenSSL's BN, as well as bc, the result of -10 % 3 is -1
# while Math::BigInt, the result is 2.
# The latter is mathematically more correct, but...
my $o1isneg = $operand1->is_neg();
$operand1->babs();
# Math::BigInt does something different with a negative modulus,
# while OpenSSL's BN and bc treat it like a positive number...
$operand2->babs();
$operand1->bmod($operand2);
if ($o1isneg) { $operand1->bneg(); }
} else {
die "SOMETHING WENT AWFULLY WRONG";
}
unshift @_, $operand1->as_hex();
}
return @_;
}
sub __power {
@_ = __paren(@_);
while (scalar @_ > 1 && $_[1] eq "^") {
my $operand1 = Math::BigInt->from_hex(__canonhex(shift));
shift;
@_ = __paren(@_);
my $operand2 = Math::BigInt->from_hex(__canonhex(shift));
$operand1->bpow($operand2);
unshift @_, $operand1->as_hex();
}
return @_;
}
# returns array ( $result, @remaining )
sub __paren {
if (scalar @_ > 0 && $_[0] eq "(") {
shift;
my @result = __adder(@_);
if (scalar @_ == 0 || $_[0] ne ")") {
return ("NaN");
}
shift;
return @result;
}
return @_;
}
1;