package Digest::base;
use strict;
use vars qw($VERSION);
$VERSION = "1.16";
# subclass is supposed to implement at least these
sub new;
sub clone;
sub add;
sub digest;
sub reset {
my $self = shift;
$self->new(@_); # ugly
}
sub addfile {
my ($self, $handle) = @_;
my $n;
my $buf = "";
while (($n = read($handle, $buf, 4*1024))) {
$self->add($buf);
}
unless (defined $n) {
require Carp;
Carp::croak("Read failed: $!");
}
$self;
}
sub add_bits {
my $self = shift;
my $bits;
my $nbits;
if (@_ == 1) {
my $arg = shift;
$bits = pack("B*", $arg);
$nbits = length($arg);
}
else {
($bits, $nbits) = @_;
}
if (($nbits % 8) != 0) {
require Carp;
Carp::croak("Number of bits must be multiple of 8 for this algorithm");
}
return $self->add(substr($bits, 0, $nbits/8));
}
sub hexdigest {
my $self = shift;
return unpack("H*", $self->digest(@_));
}
sub b64digest {
my $self = shift;
require MIME::Base64;
my $b64 = MIME::Base64::encode($self->digest(@_), "");
$b64 =~ s/=+$//;
return $b64;
}
1;
__END__
=head1 NAME
Digest::base - Digest base class
=head1 SYNOPSIS
package Digest::Foo;
use base 'Digest::base';
=head1 DESCRIPTION
The C<Digest::base> class provide implementations of the methods
C<addfile> and C<add_bits> in terms of C<add>, and of the methods
C<hexdigest> and C<b64digest> in terms of C<digest>.
Digest implementations might want to inherit from this class to get
this implementations of the alternative I<add> and I<digest> methods.
A minimal subclass needs to implement the following methods by itself:
new
clone
add
digest
The arguments and expected behaviour of these methods are described in
L<Digest>.
=head1 SEE ALSO
L<Digest>
