Base64 Encoding and Decoding

Date : May 28, 2009

At one time, I needed to encode and decode strings in Base64 but I was on a very old Perl version that does not include the MIME::Base64 core module, nor am I able to install the said module. So, here’s the source for encoding and decoding Base64 ripped from the MIME::Base64 module:

sub EncodeBase64
{
    my $s = shift ;
    my $r = '';
    while( $s =~ /(.{1,45})/gs ){
        chop( $r .= substr(pack("u",$1),1) );
    }
    my $pad=(3-length($s)%3)%3;
    $r =~ tr|` -_|AA-Za-z0-9+/|; 
    $r=~s/.{$pad}$/"="x$pad/e if $pad; 
    $r=~s/(.{1,72})/$1n/g; 
    $r; 
} 
 
sub DecodeBase64 
{ 
    my $d = shift; 
    $d =~ tr!A-Za-z0-9+/!!cd; 
    $d =~ s/=+$//; 
    $d =~ tr!A-Za-z0-9+/! -_!; 
    my $r = ''; 
    while( $d =~ /(.{1,60})/gs ){ 
        my $len = chr(32 + length($1)*3/4); 
        $r .= unpack("u", $len . $1 ); 
    } 
    $r; 
}