OpenXE/www/lib/pdf/decoders/ascii85.php
2021-05-21 08:49:41 +02:00

97 lines
2.8 KiB
PHP

<?php
//
// FPDI - Version 1.1
//
// Copyright 2004,2005 Setasign - Jan Slabon
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
if (!defined("ORD_z"))
define("ORD_z",ord('z'));
if (!defined("ORD_!"))
define("ORD_exclmark", ord('!'));
if (!defined("ORD_u"))
define("ORD_u", ord("u"));
if (!defined("ORD_tilde"))
define("ORD_tilde", ord('~'));
class ASCII85Decode {
function __construct(&$fpdi) {
$this->fpdi =& $fpdi;
}
function decode($in) {
$out = "";
$state = 0;
$chn = null;
$l = strlen($in);
for ($k = 0; $k < $l; ++$k) {
$ch = ord($in[$k]) & 0xff;
if ($ch == ORD_tilde) {
break;
}
if (preg_match("/^\s$/",chr($ch))) {
continue;
}
if ($ch == ORD_z && $state == 0) {
$out .= chr(0).chr(0).chr(0).chr(0);
continue;
}
if ($ch < ORD_exclmark || $ch > ORD_u) {
$this->fpdi->error("Illegal character in ASCII85Decode.");
}
$chn[$state++] = $ch - ORD_exclmark;
if ($state == 5) {
$state = 0;
$r = 0;
for ($j = 0; $j < 5; ++$j)
$r = $r * 85 + $chn[$j];
$out .= chr($r >> 24);
$out .= chr($r >> 16);
$out .= chr($r >> 8);
$out .= chr($r);
}
}
$r = 0;
if ($state == 1)
$this->fpdi->error("Illegal length in ASCII85Decode.");
if ($state == 2) {
$r = $chn[0] * 85 * 85 * 85 * 85 + ($chn[1]+1) * 85 * 85 * 85;
$out .= chr($r >> 24);
}
else if ($state == 3) {
$r = $chn[0] * 85 * 85 * 85 * 85 + $chn[1] * 85 * 85 * 85 + ($chn[2]+1) * 85 * 85;
$out .= chr($r >> 24);
$out .= chr($r >> 16);
}
else if ($state == 4) {
$r = $chn[0] * 85 * 85 * 85 * 85 + $chn[1] * 85 * 85 * 85 + $chn[2] * 85 * 85 + ($chn[3]+1) * 85 ;
$out .= chr($r >> 24);
$out .= chr($r >> 16);
$out .= chr($r >> 8);
}
return $out;
}
}
?>