File Coverage

blib/lib/Algorithm/HyperLogLog.pm

Criterion	Covered	Total	%
statement	38	40	95.0
branch	4	8	50.0
condition			n/a
subroutine	7	8	87.5
pod	3	3	100.0
total	52	59	88.1

package Algorithm::HyperLogLog;
use strict;
use warnings;
use 5.008008;
use Carp qw(croak);

our $VERSION = '0.23';

our $PERL_ONLY;
if ( !defined $PERL_ONLY ) {
    $PERL_ONLY = $ENV{PERL_HLL_PUREPERL} ? 1 : 0;
}

if ( !exists $INC{'Algorithm/HyperLogLog/PP.pm'} ) {
    if ( !$PERL_ONLY ) {
        require XSLoader;
        $PERL_ONLY = !eval { XSLoader::load( __PACKAGE__, $VERSION ); };
    }
    if ($PERL_ONLY) {
        require 'Algorithm/HyperLogLog/PP.pm';
    }
}

sub new_from_file {
    my ( $class, $filename ) = @_;
    open my $fh, '<', $filename or die $!;
    my $on_error = sub { close $fh; croak "Invalid dump file($filename)"; };

    binmode $fh;
    my ( @dumpdata, $buf, $readed );

    # Read register size data
    $readed = read( $fh, $buf, 1 );
    $on_error->() if $readed != 1;
    my $k = unpack 'C', $buf;

    # Read register content data
    my $m = 2**$k;
    $readed = read $fh, $buf, $m;
    $on_error->() if $readed != $m;
    close $fh;
    @dumpdata = unpack 'C*', $buf;
    my $self = $class->_new_from_dump( $k, \@dumpdata );
    return $self;
}

sub dump_to_file {
    my ( $self, $filename ) = @_;
    my $k        = log( $self->register_size ) / log(2);    # Calculate log2(register_size)
    my $dumpdata = $self->_dump_register();
    open my $fh, '>', $filename or die $!;
    binmode $fh;
    my $buf = pack 'C', $k;
    print $fh $buf;
    $buf = pack 'C*', @$dumpdata;
    print $fh $buf;
    close $fh;
}

sub XS {
    !$PERL_ONLY;
}

1;
__END__