package Digest::file;

use strict;

use Exporter ();

use Carp qw(croak);

use Digest ();

use vars qw($VERSION @ISA @EXPORT_OK);

$VERSION = "1.16";

@ISA = qw(Exporter);

@EXPORT_OK = qw(digest_file_ctx digest_file digest_file_hex digest_file_base64);

sub digest_file_ctx {

    my $file = shift;

    croak("No digest algorithm specified") unless @_;

    local *F;

    open(F, "<", $file) || croak("Can't open '$file': $!");

    binmode(F);

    my $ctx = Digest->new(@_);

    $ctx->addfile(*F);

    close(F);

    return $ctx;

}

sub digest_file {

    digest_file_ctx(@_)->digest;

}

sub digest_file_hex {

    digest_file_ctx(@_)->hexdigest;

}

sub digest_file_base64 {

    digest_file_ctx(@_)->b64digest;

}

1;

__END__

=head1 NAME

Digest::file - Calculate digests of files

=head1 SYNOPSIS

  # Poor mans "md5sum" command

  use Digest::file qw(digest_file_hex);

  for (@ARGV) {

      print digest_file_hex($_, "MD5"), "  $_\n";

  }

=head1 DESCRIPTION

This module provide 3 convenience functions to calculate the digest

of files.  The following functions are provided:

=over

=item digest_file( $file, $algorithm, [$arg,...] )

This function will calculate and return the binary digest of the bytes

of the given file.  The function will croak if it fails to open or

read the file.

The $algorithm is a string like "MD2", "MD5", "SHA-1", "SHA-512".

Additional arguments are passed to the constructor for the

implementation of the given algorithm.

=item digest_file_hex( $file, $algorithm, [$arg,...] )

Same as digest_file(), but return the digest in hex form.

=item digest_file_base64( $file, $algorithm, [$arg,...] )

Same as digest_file(), but return the digest as a base64 encoded

string.

=back

=head1 SEE ALSO

L<Digest>