clsTbsZip

Complexity

Total Complexity

180

Size/Duplication

Total Lines	997
Duplicated Lines	0.2 %

Coupling/Cohesion

Components	1
Dependencies	0

Importance

Changes

0

<?php
class clsTbsZip {
    const TBSZIP_DOWNLOAD = 1;   // download (default)
    const TBSZIP_NOHEADER = 4;   // option to use with DOWNLOAD: no header is sent
    const TBSZIP_FILE     = 8;   // output to file  , or add from file
    const TBSZIP_STRING   = 32;  // output to string, or add from string

    function __construct() {
        $this->Meth8Ok = extension_loaded('zlib'); // check if Zlib extension is available. This is need for compress and uncompress with method 8.
        $this->DisplayError = true;
        $this->ArchFile = '';
        $this->Error = false;
    }

    function CreateNew($ArchName='new.zip') {
    // Create a new virtual empty archive, the name will be the default name when the archive is flushed.
        if (!isset($this->Meth8Ok)) $this->__construct();  // for PHP 4 compatibility
        $this->Close(); // note that $this->ArchHnd is set to false here
        $this->Error = false;
        $this->ArchFile = $ArchName;
        $this->ArchIsNew = true;
        $bin = 'PK'.chr(05).chr(06).str_repeat(chr(0), 18);
        $this->CdEndPos = strlen($bin) - 4;
        $this->CdInfo = array('disk_num_curr'=>0, 'disk_num_cd'=>0, 'file_nbr_curr'=>0, 'file_nbr_tot'=>0, 'l_cd'=>0, 'p_cd'=>0, 'l_comm'=>0, 'v_comm'=>'', 'bin'=>$bin);
        $this->CdPos = $this->CdInfo['p_cd'];
    }

    function Open($ArchFile, $UseIncludePath=false) {
    // Open the zip archive
        if (!isset($this->Meth8Ok)) $this->__construct();  // for PHP 4 compatibility
        $this->Close(); // close handle and init info
        $this->Error = false;
        $this->ArchIsNew = false;
        $this->ArchIsStream = (is_resource($ArchFile) && (get_resource_type($ArchFile)=='stream'));
        if ($this->ArchIsStream) {
            $this->ArchFile = 'from_stream.zip';
            $this->ArchHnd = $ArchFile;
        } else {
            // open the file
            $this->ArchFile = $ArchFile;
            $this->ArchHnd = fopen($ArchFile, 'rb', $UseIncludePath);
        }
        $ok = !($this->ArchHnd===false);
        if ($ok) $ok = $this->CentralDirRead();
        return $ok;
    }

    function Close() {
        if (isset($this->ArchHnd) and ($this->ArchHnd!==false)) fclose($this->ArchHnd);
        $this->ArchFile = '';
        $this->ArchHnd = false;
        $this->CdInfo = array();
        $this->CdFileLst = array();
        $this->CdFileNbr = 0;
        $this->CdFileByName = array();
        $this->VisFileLst = array();
        $this->ArchCancelModif();
    }

    function ArchCancelModif() {
        $this->LastReadComp = false; // compression of the last read file (1=compressed, 0=stored not compressed, -1= stored compressed but read uncompressed)
        $this->LastReadIdx = false;  // index of the last file read
        $this->ReplInfo = array();
        $this->ReplByPos = array();
        $this->AddInfo = array();
    }

    function FileAdd($Name, $Data, $DataType=self::TBSZIP_STRING, $Compress=true) {

        if ($Data===false) return $this->FileCancelModif($Name, false); // Cancel a previously added file

        // Save information for adding a new file into the archive
        $Diff = 30 + 46 + 2*strlen($Name); // size of the header + cd info
        $Ref = $this->_DataCreateNewRef($Data, $DataType, $Compress, $Diff, $Name);
        if ($Ref===false) return false;
        $Ref['name'] = $Name;
        $this->AddInfo[] = $Ref;
        return $Ref['res'];

    }

    function CentralDirRead() {
        $cd_info = 'PK'.chr(05).chr(06); // signature of the Central Directory
        $cd_pos = -22;
        $this->_MoveTo($cd_pos, SEEK_END);
        $b = $this->_ReadData(4);
        if ($b===$cd_info) {
            $this->CdEndPos = ftell($this->ArchHnd) - 4;
        } else {
            $p = $this->_FindCDEnd($cd_info);
            //echo 'p='.var_export($p,true); exit;
            if ($p===false) {
                return $this->RaiseError('The End of Central Directory Record is not found.');
            } else {
                $this->CdEndPos = $p;
                $this->_MoveTo($p+4);
            }
        }
        $this->CdInfo = $this->CentralDirRead_End($cd_info);
        $this->CdFileLst = array();
        $this->CdFileNbr = $this->CdInfo['file_nbr_curr'];
        $this->CdPos = $this->CdInfo['p_cd'];

        if ($this->CdFileNbr<=0) return $this->RaiseError('No header found in the Central Directory.');
        if ($this->CdPos<=0) return $this->RaiseError('No position found for the Central Directory.');

        $this->_MoveTo($this->CdPos);
        for ($i=0;$i<$this->CdFileNbr;$i++) {
            $x = $this->CentralDirRead_File($i);
            if ($x!==false) {
                $this->CdFileLst[$i] = $x;
                $this->CdFileByName[$x['v_name']] = $i;
            }
        }
        return true;
    }

    function CentralDirRead_End($cd_info) {
        $b = $cd_info.$this->_ReadData(18);
        $x = array();
        $x['disk_num_curr'] = $this->_GetDec($b,4,2);  // number of this disk
        $x['disk_num_cd'] = $this->_GetDec($b,6,2);    // number of the disk with the start of the central directory
        $x['file_nbr_curr'] = $this->_GetDec($b,8,2);  // total number of entries in the central directory on this disk
        $x['file_nbr_tot'] = $this->_GetDec($b,10,2);  // total number of entries in the central directory
        $x['l_cd'] = $this->_GetDec($b,12,4);          // size of the central directory
        $x['p_cd'] = $this->_GetDec($b,16,4);          // position of start of central directory with respect to the starting disk number
        $x['l_comm'] = $this->_GetDec($b,20,2);        // .ZIP file comment length
        $x['v_comm'] = $this->_ReadData($x['l_comm']); // .ZIP file comment
        $x['bin'] = $b.$x['v_comm'];
        return $x;
    }

    function CentralDirRead_File($idx) {

        $b = $this->_ReadData(46);

        $x = $this->_GetHex($b,0,4);
        if ($x!=='h:02014b50') return $this->RaiseError("Signature of Central Directory Header #".$idx." (file information) expected but not found at position ".$this->_TxtPos(ftell($this->ArchHnd) - 46).".");

        $x = array();
        $x['vers_used'] = $this->_GetDec($b,4,2);
        $x['vers_necess'] = $this->_GetDec($b,6,2);
        $x['purp'] = $this->_GetBin($b,8,2);
        $x['meth'] = $this->_GetDec($b,10,2);
        $x['time'] = $this->_GetDec($b,12,2);
        $x['date'] = $this->_GetDec($b,14,2);
        $x['crc32'] = $this->_GetDec($b,16,4);
        $x['l_data_c'] = $this->_GetDec($b,20,4);
        $x['l_data_u'] = $this->_GetDec($b,24,4);
        $x['l_name'] = $this->_GetDec($b,28,2);
        $x['l_fields'] = $this->_GetDec($b,30,2);
        $x['l_comm'] = $this->_GetDec($b,32,2);
        $x['disk_num'] = $this->_GetDec($b,34,2);
        $x['int_file_att'] = $this->_GetDec($b,36,2);
        $x['ext_file_att'] = $this->_GetDec($b,38,4);
        $x['p_loc'] = $this->_GetDec($b,42,4);
        $x['v_name'] = $this->_ReadData($x['l_name']);
        $x['v_fields'] = $this->_ReadData($x['l_fields']);
        $x['v_comm'] = $this->_ReadData($x['l_comm']);

        $x['bin'] = $b.$x['v_name'].$x['v_fields'].$x['v_comm'];

        return $x;
    }

    function RaiseError($Msg) {
        if ($this->DisplayError) {
            if (PHP_SAPI==='cli') {
                echo get_class($this).' ERROR with the zip archive: '.$Msg."\r\n";
            } else {
                echo '<strong>'.get_class($this).' ERROR with the zip archive:</strong> '.$Msg.'<br>'."\r\n";
            }
        }
        $this->Error = $Msg;
        return false;
    }

    function Debug($FileHeaders=false) {

        $this->DisplayError = true;

        if ($FileHeaders) {
            // Calculations first in order to have error messages before other information
            $idx = 0;
            $pos = 0;
            $pos_stop = $this->CdInfo['p_cd'];
            $this->_MoveTo($pos);
            while ( ($pos<$pos_stop) && ($ok = $this->_ReadFile($idx,false)) ) {
                $this->VisFileLst[$idx]['p_this_header (debug_mode only)'] = $pos;
                $pos = ftell($this->ArchHnd);
                $idx++;
            }
        }

        $nl = "\r\n";
        echo "<pre>";

        echo "-------------------------------".$nl;
        echo "End of Central Directory record".$nl;
        echo "-------------------------------".$nl;
        print_r($this->DebugArray($this->CdInfo));

        echo $nl;
        echo "-------------------------".$nl;
        echo "Central Directory headers".$nl;
        echo "-------------------------".$nl;
        print_r($this->DebugArray($this->CdFileLst));

        if ($FileHeaders) {
            echo $nl;
            echo "------------------".$nl;
            echo "Local File headers".$nl;
            echo "------------------".$nl;
            print_r($this->DebugArray($this->VisFileLst));
        }

        echo "</pre>";

    }

    function DebugArray($arr) {
        foreach ($arr as $k=>$v) {
            if (is_array($v)) {
                $arr[$k] = $this->DebugArray($v);
            } elseif (substr($k,0,2)=='p_') {
                $arr[$k] = $this->_TxtPos($v);
            }
        }
        return $arr;
    }

    function FileExists($NameOrIdx) {
        return ($this->FileGetIdx($NameOrIdx)!==false);
    }

    function FileGetIdx($NameOrIdx) {
    // Check if a file name, or a file index exists in the Central Directory, and return its index
        if (is_string($NameOrIdx)) {
            if (isset($this->CdFileByName[$NameOrIdx])) {
                return $this->CdFileByName[$NameOrIdx];
            } else {
                return false;
            }
        } else {
            if (isset($this->CdFileLst[$NameOrIdx])) {
                return $NameOrIdx;
            } else {
                return false;
            }
        }
    }

    function FileGetIdxAdd($Name) {
    // Check if a file name exists in the list of file to add, and return its index
        if (!is_string($Name)) return false;
        $idx_lst = array_keys($this->AddInfo);
        foreach ($idx_lst as $idx) {
            if ($this->AddInfo[$idx]['name']===$Name) return $idx;
        }
        return false;
    }

    function FileRead($NameOrIdx, $Uncompress=true) {

        $this->LastReadComp = false; // means the file is not found
        $this->LastReadIdx = false;

        $idx = $this->FileGetIdx($NameOrIdx);
        if ($idx===false) return $this->RaiseError('File "'.$NameOrIdx.'" is not found in the Central Directory.');

        $pos = $this->CdFileLst[$idx]['p_loc'];
        $this->_MoveTo($pos);

        $this->LastReadIdx = $idx; // Can be usefull to get the idx

        $Data = $this->_ReadFile($idx, true);

        // Manage uncompression
        $Comp = 1; // means the contents stays compressed
        $meth = $this->CdFileLst[$idx]['meth'];
        if ($meth==8) {
            if ($Uncompress) {
                if ($this->Meth8Ok) {
                    $Data = gzinflate($Data);
                    $Comp = -1; // means uncompressed
                } else {
                    $this->RaiseError('Unable to uncompress file "'.$NameOrIdx.'" because extension Zlib is not installed.');
                }
            }
        } elseif($meth==0) {
            $Comp = 0; // means stored without compression
        } else {
            if ($Uncompress) $this->RaiseError('Unable to uncompress file "'.$NameOrIdx.'" because it is compressed with method '.$meth.'.');
        }
        $this->LastReadComp = $Comp;

        return $Data;

    }

    function _ReadFile($idx, $ReadData) {
    // read the file header (and maybe the data ) in the archive, assuming the cursor in at a new file position

        $b = $this->_ReadData(30);

        $x = $this->_GetHex($b,0,4);
        if ($x!=='h:04034b50') return $this->RaiseError("Signature of Local File Header #".$idx." (data section) expected but not found at position ".$this->_TxtPos(ftell($this->ArchHnd)-30).".");

        $x = array();
        $x['vers'] = $this->_GetDec($b,4,2);
        $x['purp'] = $this->_GetBin($b,6,2);
        $x['meth'] = $this->_GetDec($b,8,2);
        $x['time'] = $this->_GetDec($b,10,2);
        $x['date'] = $this->_GetDec($b,12,2);
        $x['crc32'] = $this->_GetDec($b,14,4);
        $x['l_data_c'] = $this->_GetDec($b,18,4);
        $x['l_data_u'] = $this->_GetDec($b,22,4);
        $x['l_name'] = $this->_GetDec($b,26,2);
        $x['l_fields'] = $this->_GetDec($b,28,2);
        $x['v_name'] = $this->_ReadData($x['l_name']);
        $x['v_fields'] = $this->_ReadData($x['l_fields']);

        $x['bin'] = $b.$x['v_name'].$x['v_fields'];

        // Read Data
        if (isset($this->CdFileLst[$idx])) {
            $len_cd = $this->CdFileLst[$idx]['l_data_c'];
            if ($x['l_data_c']==0) {
                // Sometimes, the size is not specified in the local information.
                $len = $len_cd;
            } else {
                $len = $x['l_data_c'];
                if ($len!=$len_cd) {
                    //echo "TbsZip Warning: Local information for file #".$idx." says len=".$len.", while Central Directory says len=".$len_cd.".";
                }
            }
        } else {
            $len = $x['l_data_c'];
            if ($len==0) $this->RaiseError("File Data #".$idx." cannt be read because no length is specified in the Local File Header and its Central Directory information has not been found.");
        }

        if ($ReadData) {
            $Data = $this->_ReadData($len);
        } else {
            $this->_MoveTo($len, SEEK_CUR);
        }

        // Description information
        $desc_ok = ($x['purp'][2+3]=='1');
        if ($desc_ok) {
            $b = $this->_ReadData(12);
            $s = $this->_GetHex($b,0,4);
            $d = 0;
            // the specification says the signature may or may not be present
            if ($s=='h:08074b50') {
                $b .= $this->_ReadData(4);
                $d = 4;
                $x['desc_bin'] = $b;
                $x['desc_sign'] = $s;
            } else {
                $x['desc_bin'] = $b;
            }
            $x['desc_crc32']    = $this->_GetDec($b,0+$d,4);
            $x['desc_l_data_c'] = $this->_GetDec($b,4+$d,4);
            $x['desc_l_data_u'] = $this->_GetDec($b,8+$d,4);
        }

        // Save file info without the data
        $this->VisFileLst[$idx] = $x;

        // Return the info
        if ($ReadData) {
            return $Data;
        } else {
            return true;
        }

    }

    function FileReplace($NameOrIdx, $Data, $DataType=self::TBSZIP_STRING, $Compress=true) {
    // Store replacement information.

        $idx = $this->FileGetIdx($NameOrIdx);
        if ($idx===false) return $this->RaiseError('File "'.$NameOrIdx.'" is not found in the Central Directory.');

        $pos = $this->CdFileLst[$idx]['p_loc'];

        if ($Data===false) {
            // file to delete
            $this->ReplInfo[$idx] = false;
            $Result = true;
        } else {
            // file to replace
            $Diff = - $this->CdFileLst[$idx]['l_data_c'];
            $Ref = $this->_DataCreateNewRef($Data, $DataType, $Compress, $Diff, $NameOrIdx);
            if ($Ref===false) return false;
            $this->ReplInfo[$idx] = $Ref;
            $Result = $Ref['res'];
        }

        $this->ReplByPos[$pos] = $idx;

        return $Result;

    }

    /**
     * Return the state of the file.
     * @return {string} 'u'=unchanged, 'm'=modified, 'd'=deleted, 'a'=added, false=unknown
     */
    function FileGetState($NameOrIdx) {

        $idx = $this->FileGetIdx($NameOrIdx);
        if ($idx===false) {
            $idx = $this->FileGetIdxAdd($NameOrIdx);
            if ($idx===false) {
                return false;
            } else {
                return 'a';
            }
        } elseif (isset($this->ReplInfo[$idx])) {
            if ($this->ReplInfo[$idx]===false) {
                return 'd';
            } else {
                return 'm';
            }
        } else {
            return 'u';
        }

    }

    function FileCancelModif($NameOrIdx, $ReplacedAndDeleted=true) {
    // cancel added, modified or deleted modifications on a file in the archive
    // return the number of cancels

        $nbr = 0;

        if ($ReplacedAndDeleted) {
            // replaced or deleted files
            $idx = $this->FileGetIdx($NameOrIdx);
            if ($idx!==false) {
                if (isset($this->ReplInfo[$idx])) {
                    $pos = $this->CdFileLst[$idx]['p_loc'];
                    unset($this->ReplByPos[$pos]);
                    unset($this->ReplInfo[$idx]);
                    $nbr++;
                }
            }
        }

        // added files
        $idx = $this->FileGetIdxAdd($NameOrIdx);
        if ($idx!==false) {
            unset($this->AddInfo[$idx]);
            $nbr++;
        }

        return $nbr;

    }

    function Flush($Render=self::TBSZIP_DOWNLOAD, $File='', $ContentType='') {

        if ( ($File!=='') && ($this->ArchFile===$File) && ($Render==self::TBSZIP_FILE) ) {
            $this->RaiseError('Method Flush() cannot overwrite the current opened archive: \''.$File.'\''); // this makes corrupted zip archives without PHP error.
            return false;
        }

        $ArchPos = 0;
        $Delta = 0;
        $FicNewPos = array();
        $DelLst = array(); // idx of deleted files
        $DeltaCdLen = 0; // delta of the CD's size

        $now = time();
        $date  = $this->_MsDos_Date($now);
        $time  = $this->_MsDos_Time($now);

        if (!$this->OutputOpen($Render, $File, $ContentType)) return false;

        // output modified zipped files and unmodified zipped files that are beetween them
        ksort($this->ReplByPos);
        foreach ($this->ReplByPos as $ReplPos => $ReplIdx) {
            // output data from the zip archive which is before the data to replace
            $this->OutputFromArch($ArchPos, $ReplPos);
            // get current file information
            if (!isset($this->VisFileLst[$ReplIdx])) $this->_ReadFile($ReplIdx, false);
            $FileInfo =& $this->VisFileLst[$ReplIdx];
            $b1 = $FileInfo['bin'];
            if (isset($FileInfo['desc_bin'])) {
                $b2 = $FileInfo['desc_bin'];
            } else {
                $b2 = '';
            }
            $info_old_len = strlen($b1) + $this->CdFileLst[$ReplIdx]['l_data_c'] + strlen($b2); // $FileInfo['l_data_c'] may have a 0 value in some archives
            // get replacement information
            $ReplInfo =& $this->ReplInfo[$ReplIdx];
            if ($ReplInfo===false) {
                // The file is to be deleted
                $Delta = $Delta - $info_old_len; // headers and footers are also deleted
                $DelLst[$ReplIdx] = true;
            } else {
                // prepare the header of the current file
                $this->_DataPrepare($ReplInfo); // get data from external file if necessary
                $this->_PutDec($b1, $time, 10, 2); // time
                $this->_PutDec($b1, $date, 12, 2); // date
                $this->_PutDec($b1, $ReplInfo['crc32'], 14, 4); // crc32
                $this->_PutDec($b1, $ReplInfo['len_c'], 18, 4); // l_data_c
                $this->_PutDec($b1, $ReplInfo['len_u'], 22, 4); // l_data_u
                if ($ReplInfo['meth']!==false) $this->_PutDec($b1, $ReplInfo['meth'], 8, 2); // meth
                // prepare the bottom description if the zipped file, if any
                if ($b2!=='') {
                    $d = (strlen($b2)==16) ? 4 : 0; // offset because of the signature if any
                    $this->_PutDec($b2, $ReplInfo['crc32'], $d+0, 4); // crc32
                    $this->_PutDec($b2, $ReplInfo['len_c'], $d+4, 4); // l_data_c
                    $this->_PutDec($b2, $ReplInfo['len_u'], $d+8, 4); // l_data_u
                }
                // output data
                $this->OutputFromString($b1.$ReplInfo['data'].$b2);
                unset($ReplInfo['data']); // save PHP memory
                $Delta = $Delta + $ReplInfo['diff'] + $ReplInfo['len_c'];
            }
            // Update the delta of positions for zipped files which are physically after the currently replaced one
            for ($i=0;$i<$this->CdFileNbr;$i++) {
                if ($this->CdFileLst[$i]['p_loc']>$ReplPos) {
                    $FicNewPos[$i] = $this->CdFileLst[$i]['p_loc'] + $Delta;
                }
            }
            // Update the current pos in the archive
            $ArchPos = $ReplPos + $info_old_len;
        }

        // Ouput all the zipped files that remain before the Central Directory listing
        if ($this->ArchHnd!==false) $this->OutputFromArch($ArchPos, $this->CdPos); // ArchHnd is false if CreateNew() has been called
        $ArchPos = $this->CdPos;

        // Output file to add
        $AddNbr = count($this->AddInfo);
        $AddDataLen = 0; // total len of added data (inlcuding file headers)
        if ($AddNbr>0) {
            $AddPos = $ArchPos + $Delta; // position of the start
            $AddLst = array_keys($this->AddInfo);
            foreach ($AddLst as $idx) {
                $n = $this->_DataOuputAddedFile($idx, $AddPos);
                $AddPos += $n;
                $AddDataLen += $n;
            }
        }

        // Modifiy file information in the Central Directory for replaced files
        $b2 = '';
        $old_cd_len = 0;
        for ($i=0;$i<$this->CdFileNbr;$i++) {
            $b1 = $this->CdFileLst[$i]['bin'];
            $old_cd_len += strlen($b1);
            if (!isset($DelLst[$i])) {
                if (isset($FicNewPos[$i])) $this->_PutDec($b1, $FicNewPos[$i], 42, 4);   // p_loc
                if (isset($this->ReplInfo[$i])) {
                    $ReplInfo =& $this->ReplInfo[$i];
                    $this->_PutDec($b1, $time, 12, 2); // time
                    $this->_PutDec($b1, $date, 14, 2); // date
                    $this->_PutDec($b1, $ReplInfo['crc32'], 16, 4); // crc32
                    $this->_PutDec($b1, $ReplInfo['len_c'], 20, 4); // l_data_c
                    $this->_PutDec($b1, $ReplInfo['len_u'], 24, 4); // l_data_u
                    if ($ReplInfo['meth']!==false) $this->_PutDec($b1, $ReplInfo['meth'], 10, 2); // meth
                }
                $b2 .= $b1;
            }
        }
        $this->OutputFromString($b2);
        $ArchPos += $old_cd_len;
        $DeltaCdLen =  $DeltaCdLen + strlen($b2) - $old_cd_len;

        // Output until "end of central directory record"
        if ($this->ArchHnd!==false) $this->OutputFromArch($ArchPos, $this->CdEndPos); // ArchHnd is false if CreateNew() has been called

        // Output file information of the Central Directory for added files
        if ($AddNbr>0) {
            $b2 = '';
            foreach ($AddLst as $idx) {
                $b2 .= $this->AddInfo[$idx]['bin'];
            }
            $this->OutputFromString($b2);
            $DeltaCdLen += strlen($b2);
        }

        // Output "end of central directory record"
        $b2 = $this->CdInfo['bin'];
        $DelNbr = count($DelLst);
        if ( ($AddNbr>0) or ($DelNbr>0) ) {
            // total number of entries in the central directory on this disk
            $n = $this->_GetDec($b2, 8, 2);
            $this->_PutDec($b2, $n + $AddNbr - $DelNbr,  8, 2);
            // total number of entries in the central directory
            $n = $this->_GetDec($b2, 10, 2);
            $this->_PutDec($b2, $n + $AddNbr - $DelNbr, 10, 2);
            // size of the central directory
            $n = $this->_GetDec($b2, 12, 4);
            $this->_PutDec($b2, $n + $DeltaCdLen, 12, 4);
            $Delta = $Delta + $AddDataLen;
        }
        $this->_PutDec($b2, $this->CdPos+$Delta , 16, 4); // p_cd  (offset of start of central directory with respect to the starting disk number)
        $this->OutputFromString($b2);

        $this->OutputClose();

        return true;

    }

    // ----------------
    // output functions
    // ----------------

    function OutputOpen($Render, $File, $ContentType) {

        if (($Render & self::TBSZIP_FILE)==self::TBSZIP_FILE) {
            $this->OutputMode = self::TBSZIP_FILE;
            if (''.$File=='') $File = basename($this->ArchFile).'.zip';
            $this->OutputHandle = @fopen($File, 'w');
            if ($this->OutputHandle===false) {
                return $this->RaiseError('Method Flush() cannot overwrite the target file \''.$File.'\'. This may not be a valid file path or the file may be locked by another process or because of a denied permission.');
            }
        } elseif (($Render & self::TBSZIP_STRING)==self::TBSZIP_STRING) {
            $this->OutputMode = self::TBSZIP_STRING;
            $this->OutputSrc = '';
        } elseif (($Render & self::TBSZIP_DOWNLOAD)==self::TBSZIP_DOWNLOAD) {
            $this->OutputMode = self::TBSZIP_DOWNLOAD;
            // Output the file
            if (''.$File=='') $File = basename($this->ArchFile);
            if (($Render & self::TBSZIP_NOHEADER)==self::TBSZIP_NOHEADER) {
            } else {
                header ('Pragma: no-cache');
                if ($ContentType!='') header ('Content-Type: '.$ContentType);
                header('Content-Disposition: attachment; filename="'.$File.'"');
                header('Expires: 0');
                header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
                header('Cache-Control: public');
                header('Content-Description: File Transfer');
                header('Content-Transfer-Encoding: binary');
                $Len = $this->_EstimateNewArchSize();
                if ($Len!==false) header('Content-Length: '.$Len);
            }
        } else {
            return $this->RaiseError('Method Flush is called with a unsupported render option.');
        }

        return true;

    }

    function OutputFromArch($pos, $pos_stop) {
        $len = $pos_stop - $pos;
        if ($len<0) return;
        $this->_MoveTo($pos);
        $block = 1024;
        while ($len>0) {
            $l = min($len, $block);
            $x = $this->_ReadData($l);
            $this->OutputFromString($x);
            $len = $len - $l;
        }
        unset($x);
    }

    function OutputFromString($data) {
        if ($this->OutputMode===self::TBSZIP_DOWNLOAD) {
            echo $data; // donwload
        } elseif ($this->OutputMode===self::TBSZIP_STRING) {
            $this->OutputSrc .= $data; // to string
        } elseif (self::TBSZIP_FILE) {
            fwrite($this->OutputHandle, $data); // to file
        }
    }

    function OutputClose() {
        if ( ($this->OutputMode===self::TBSZIP_FILE) && ($this->OutputHandle!==false) ) {
            fclose($this->OutputHandle);
            $this->OutputHandle = false;
        }
    }

    // ----------------
    // Reading functions
    // ----------------

    function _MoveTo($pos, $relative = SEEK_SET) {
        fseek($this->ArchHnd, $pos, $relative);
    }

    function _ReadData($len) {
        if ($len>0) {
            $x = fread($this->ArchHnd, $len);
            return $x;
        } else {
            return '';
        }
    }

    // ----------------
    // Take info from binary data
    // ----------------

    function _GetDec($txt, $pos, $len) {
        $x = substr($txt, $pos, $len);
        $z = 0;
        for ($i=0;$i<$len;$i++) {
            $asc = ord($x[$i]);
            if ($asc>0) $z = $z + $asc*pow(256,$i);
        }
        return $z;
    }

    function _GetHex($txt, $pos, $len) {
        $x = substr($txt, $pos, $len);
        return 'h:'.bin2hex(strrev($x));
    }

    function _GetBin($txt, $pos, $len) {
        $x = substr($txt, $pos, $len);
        $z = '';
        for ($i=0;$i<$len;$i++) {
            $asc = ord($x[$i]);
            if (isset($x[$i])) {
                for ($j=0;$j<8;$j++) {
                    $z .= ($asc & pow(2,$j)) ? '1' : '0';
                }
            } else {
                $z .= '00000000';
            }
        }
        return 'b:'.$z;
    }

    // ----------------
    // Put info into binary data
    // ----------------

    function _PutDec(&$txt, $val, $pos, $len) {
        $x = '';
        for ($i=0;$i<$len;$i++) {
            if ($val==0) {
                $z = 0;
            } else {
                $z = intval($val % 256);
                if (($val<0) && ($z!=0)) { // ($z!=0) is very important, example: val=-420085702
                    // special opration for negative value. If the number id too big, PHP stores it into a signed integer. For example: crc32('coucou') => -256185401 instead of  4038781895. NegVal = BigVal - (MaxVal+1) = BigVal - 256^4
                    $val = ($val - $z)/256 -1;
                    $z = 256 + $z;
                } else {
                    $val = ($val - $z)/256;
                }
            }
            $x .= chr($z);
        }
        $txt = substr_replace($txt, $x, $pos, $len);
    }

    function _MsDos_Date($Timestamp = false) {
        // convert a date-time timstamp into the MS-Dos format
        $d = ($Timestamp===false) ? getdate() : getdate($Timestamp);
        return (($d['year']-1980)*512) + ($d['mon']*32) + $d['mday'];
    }
    function _MsDos_Time($Timestamp = false) {
        // convert a date-time timstamp into the MS-Dos format
        $d = ($Timestamp===false) ? getdate() : getdate($Timestamp);
        return ($d['hours']*2048) + ($d['minutes']*32) + intval($d['seconds']/2); // seconds are rounded to an even number in order to save 1 bit
    }

    function _MsDos_Debug($date, $time) {
        // Display the formated date and time. Just for debug purpose.
        // date end time are encoded on 16 bits (2 bytes) : date = yyyyyyymmmmddddd , time = hhhhhnnnnnssssss
        $y = ($date & 65024)/512 + 1980;
        $m = ($date & 480)/32;
        $d = ($date & 31);
        $h = ($time & 63488)/2048;
        $i = ($time & 1984)/32;
        $s = ($time & 31) * 2; // seconds have been rounded to an even number in order to save 1 bit
        return $y.'-'.str_pad($m,2,'0',STR_PAD_LEFT).'-'.str_pad($d,2,'0',STR_PAD_LEFT).' '.str_pad($h,2,'0',STR_PAD_LEFT).':'.str_pad($i,2,'0',STR_PAD_LEFT).':'.str_pad($s,2,'0',STR_PAD_LEFT);
    }

    function _TxtPos($pos) {
        // Return the human readable position in both decimal and hexa
        return $pos." (h:".dechex($pos).")";
    }

    /**
     * Search the record of end of the Central Directory.
     * Return the position of the record in the file.
     * Return false if the record is not found. The comment cannot exceed 65335 bytes (=FFFF).
     * The method is read backwards a block of 256 bytes and search the key in this block.
     */
    function _FindCDEnd($cd_info) {
        $nbr = 1;
        $p = false;
        $pos = ftell($this->ArchHnd) - 4 - 256;
        while ( ($p===false) && ($nbr<256) ) {
            if ($pos<=0) {
                $pos = 0;
                $nbr = 256; // in order to make this a last check
            }
            $this->_MoveTo($pos);
            $x = $this->_ReadData(256);
            $p = strpos($x, $cd_info);
            if ($p===false) {
                $nbr++;
                $pos = $pos - 256 - 256;
            } else {
                return $pos + $p;
            }
        }
        return false;
    }

    function _DataOuputAddedFile($Idx, $PosLoc) {

        $Ref =& $this->AddInfo[$Idx];
        $this->_DataPrepare($Ref); // get data from external file if necessary

        // Other info
        $file_time = $Ref['file_time'] !== false ? $Ref['file_time'] : time();
        $date  = $this->_MsDos_Date($file_time);
        $time  = $this->_MsDos_Time($file_time);
        $len_n = strlen($Ref['name']);
        $purp  = 2048 ; // purpose // +8 to indicates that there is an extended local header

        // Header for file in the data section
        $b = 'PK'.chr(03).chr(04).str_repeat(' ',26); // signature
        $this->_PutDec($b,20,4,2); //vers = 20
        $this->_PutDec($b,$purp,6,2); // purp
        $this->_PutDec($b,$Ref['meth'],8,2);  // meth
        $this->_PutDec($b,$time,10,2); // time
        $this->_PutDec($b,$date,12,2); // date
        $this->_PutDec($b,$Ref['crc32'],14,4); // crc32
        $this->_PutDec($b,$Ref['len_c'],18,4); // l_data_c
        $this->_PutDec($b,$Ref['len_u'],22,4); // l_data_u
        $this->_PutDec($b,$len_n,26,2); // l_name
        $this->_PutDec($b,0,28,2); // l_fields
        $b .= $Ref['name']; // name
        $b .= ''; // fields

        // Output the data
        $this->OutputFromString($b.$Ref['data']);
        $OutputLen = strlen($b) + $Ref['len_c']; // new position of the cursor
        unset($Ref['data']); // save PHP memory

        // Information for file in the Central Directory
        $b = 'PK'.chr(01).chr(02).str_repeat(' ',42); // signature
        $this->_PutDec($b,20,4,2);  // vers_used = 20
        $this->_PutDec($b,20,6,2);  // vers_necess = 20
        $this->_PutDec($b,$purp,8,2);  // purp
        $this->_PutDec($b,$Ref['meth'],10,2); // meth
        $this->_PutDec($b,$time,12,2); // time
        $this->_PutDec($b,$date,14,2); // date
        $this->_PutDec($b,$Ref['crc32'],16,4); // crc32
        $this->_PutDec($b,$Ref['len_c'],20,4); // l_data_c
        $this->_PutDec($b,$Ref['len_u'],24,4); // l_data_u
        $this->_PutDec($b,$len_n,28,2); // l_name
        $this->_PutDec($b,0,30,2); // l_fields
        $this->_PutDec($b,0,32,2); // l_comm
        $this->_PutDec($b,0,34,2); // disk_num
        $this->_PutDec($b,0,36,2); // int_file_att
        $this->_PutDec($b,0,38,4); // ext_file_att
        $this->_PutDec($b,$PosLoc,42,4); // p_loc
        $b .= $Ref['name']; // v_name
        $b .= ''; // v_fields
        $b .= ''; // v_comm

        $Ref['bin'] = $b;

        return $OutputLen;

    }

    function _DataCreateNewRef($Data, $DataType, $Compress, $Diff, $NameOrIdx) {

        $file_time = false;
        if (is_array($Compress)) {
            $result = 2;
            $meth = $Compress['meth'];
            $len_u = $Compress['len_u'];
            $crc32 = $Compress['crc32'];
            $Compress = false;
        } elseif ($Compress and ($this->Meth8Ok)) {
            $result = 1;
            $meth = 8;
            $len_u = false; // means unknown
            $crc32 = false;
        } else {
            $result = ($Compress) ? -1 : 0;
            $meth = 0;
            $len_u = false;
            $crc32 = false;
            $Compress = false;
        }

        // TODO support for data taken from okapi cache
        if ($DataType==self::TBSZIP_STRING) {
            $path = false;
            if ($Compress) {
                // we compress now in order to save PHP memory
                $len_u = strlen($Data);
                $crc32 = crc32($Data);
                $Data = gzdeflate($Data);
                $len_c = strlen($Data);
            } else {
                $len_c = strlen($Data);
                if ($len_u===false) {
                    $len_u = $len_c;
                    $crc32 = crc32($Data);
                }
            }
        } else {
            $path = $Data;
            $Data = false;
            $fi = stat($path);
            if ($fi !== false) {
                $fz = $fi['size'];
                if ($len_u===false) $len_u = $fz;
                $len_c = ($Compress) ? false : $fz;
                $file_time = $fi['mtime'];
            } else {
                return $this->RaiseError("Cannot add the file '".$path."' because it is not found.");
            }
        }

        // at this step $Data and $crc32 can be false only in case of external file, and $len_c is false only in case of external file to compress
        return array('data'=>$Data, 'path'=>$path, 'meth'=>$meth, 'len_u'=>$len_u, 'len_c'=>$len_c,
                'crc32'=>$crc32, 'diff'=>$Diff, 'res'=>$result, 'file_time'=>$file_time);

    }

    function _DataPrepare(&$Ref) {
        // returns the real size of data
        // TODO: support for data returned from okapi cache
        if ($Ref['path']!==false) {
            $Ref['data'] = file_get_contents($Ref['path']);
            if ($Ref['crc32']===false) $Ref['crc32'] = crc32($Ref['data']);
            if ($Ref['len_c']===false) {
                // means the data must be compressed
                $Ref['data'] = gzdeflate($Ref['data']);
                $Ref['len_c'] = strlen($Ref['data']);
            }
        }
    }
    /**
     * Return the size of the new archive, or false if it cannot be calculated (because of external file that must be compressed before to be insered)
     */
    function _EstimateNewArchSize($Optim=true) {

        if ($this->ArchIsNew) {
            $Len = strlen($this->CdInfo['bin']);
        } elseif ($this->ArchIsStream) {
            $x = fstat($this->ArchHnd);
            $Len = $x['size'];
        } else {
            $Len = filesize($this->ArchFile);
        }

        // files to replace or delete
        foreach ($this->ReplByPos as $i) {
            $Ref =& $this->ReplInfo[$i];
            if ($Ref===false) {
                // file to delete
                $Info =& $this->CdFileLst[$i];
                if (!isset($this->VisFileLst[$i])) {
                    if ($Optim) return false; // if $Optimization is set to true, then we d'ont rewind to read information
                    $this->_MoveTo($Info['p_loc']);
                    $this->_ReadFile($i, false);
                }
                $Vis =& $this->VisFileLst[$i];
                $Len += -strlen($Vis['bin']) -strlen($Info['bin']) - $Info['l_data_c'];
                if (isset($Vis['desc_bin'])) $Len += -strlen($Vis['desc_bin']);
            } elseif ($Ref['len_c']===false) {
                return false; // information not yet known
            } else {
                // file to replace
                $Len += $Ref['len_c'] + $Ref['diff'];
            }
        }

        // files to add
        $i_lst = array_keys($this->AddInfo);
        foreach ($i_lst as $i) {
            $Ref =& $this->AddInfo[$i];
            if ($Ref['len_c']===false) {
                return false; // information not yet known
            } else {
                $Len += $Ref['len_c'] + $Ref['diff'];
            }
        }

        return $Len;

    }

}