D'oh! Forgot to lib/Digest/base.pm

p4raw-id: //depot/perl@21809

1 files changed, 100 insertions, 0 deletions

diff --git a/lib/Digest/base.pm b/lib/Digest/base.pm
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+package Digest::base;
+
+use strict;
+use vars qw($VERSION);
+$VERSION = "1.00";
+
+# 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 SYNPOSIS
+
+  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>