ole.php

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    * creates an OLE_PPS object for each one.
    *
    * @access private
    * @param integer $blockId the block id of the first block
    * @return mixed true on success, PEAR_Error on failure
    */
    function _readPpsWks($blockId)
    {
        $fh = $this->getStream($blockId);
        for ($pos = 0; ; $pos += 128) {
            fseek($fh, $pos, SEEK_SET);
            $nameUtf16 = fread($fh, 64);
            $nameLength = $this->_readInt2($fh);
            $nameUtf16 = substr($nameUtf16, 0, $nameLength - 2);
            // Simple conversion from UTF-16LE to ISO-8859-1
            $name = str_replace("\x00", "", $nameUtf16);
            $type = $this->_readInt1($fh);
            switch ($type) {
            case OLE_PPS_TYPE_ROOT:
                require_once 'OLE/PPS/Root.php';
                $pps = new OLE_PPS_Root(null, null, array());
                $this->root = $pps;
                break;
            case OLE_PPS_TYPE_DIR:
                $pps = new OLE_PPS(null, null, null, null, null,
                                   null, null, null, null, array());
                break;
            case OLE_PPS_TYPE_FILE:
                require_once 'OLE/PPS/File.php';
                $pps = new OLE_PPS_File($name);
                break;
            default:
                continue;
            }
            fseek($fh, 1, SEEK_CUR);
            $pps->Type    = $type;
            $pps->Name    = $name;
            $pps->PrevPps = $this->_readInt4($fh);
            $pps->NextPps = $this->_readInt4($fh);
            $pps->DirPps  = $this->_readInt4($fh);
            fseek($fh, 20, SEEK_CUR);
            $pps->Time1st = OLE::OLE2LocalDate(fread($fh, 8));
            $pps->Time2nd = OLE::OLE2LocalDate(fread($fh, 8));
            $pps->_StartBlock = $this->_readInt4($fh);
            $pps->Size = $this->_readInt4($fh);
            $pps->No = count($this->_list);
            $this->_list[] = $pps;

            // check if the PPS tree (starting from root) is complete
            if (isset($this->root) &&
                $this->_ppsTreeComplete($this->root->No)) {

                break;
            }
        }
        fclose($fh);

        // Initialize $pps->children on directories
        foreach ($this->_list as $pps) {
            if ($pps->Type == OLE_PPS_TYPE_DIR || $pps->Type == OLE_PPS_TYPE_ROOT) {
                $nos = array($pps->DirPps);
                $pps->children = array();
                while ($nos) {
                    $no = array_pop($nos);
                    if ($no != -1) {
                        $childPps = $this->_list[$no];
                        $nos[] = $childPps->PrevPps;
                        $nos[] = $childPps->NextPps;
                        $pps->children[] = $childPps;
                    }
                }
            }
        }

        return true;
    }

    /**
    * It checks whether the PPS tree is complete (all PPS's read)
    * starting with the given PPS (not necessarily root)
    *
    * @access private
    * @param integer $index The index of the PPS from which we are checking
    * @return boolean Whether the PPS tree for the given PPS is complete
    */
    function _ppsTreeComplete($index)
    {
        return isset($this->_list[$index]) &&
               ($pps = $this->_list[$index]) &&
               ($pps->PrevPps == -1 ||
                $this->_ppsTreeComplete($pps->PrevPps)) &&
               ($pps->NextPps == -1 ||
                $this->_ppsTreeComplete($pps->NextPps)) &&
               ($pps->DirPps == -1 ||
                $this->_ppsTreeComplete($pps->DirPps));
    }

    /** 
    * Checks whether a PPS is a File PPS or not.
    * If there is no PPS for the index given, it will return false.
    * @param integer $index The index for the PPS
    * @return bool true if it's a File PPS, false otherwise
    * @access public
    */
    function isFile($index)
    {
        if (isset($this->_list[$index])) {
            return ($this->_list[$index]->Type == OLE_PPS_TYPE_FILE);
        }
        return false;
    }

    /** 
    * Checks whether a PPS is a Root PPS or not.
    * If there is no PPS for the index given, it will return false.
    * @param integer $index The index for the PPS.
    * @return bool true if it's a Root PPS, false otherwise
    * @access public
    */
    function isRoot($index)
    {
        if (isset($this->_list[$index])) {
            return ($this->_list[$index]->Type == OLE_PPS_TYPE_ROOT);
        }
        return false;
    }

    /** 
    * Gives the total number of PPS's found in the OLE container.
    * @return integer The total number of PPS's found in the OLE container
    * @access public
    */
    function ppsTotal()
    {
        return count($this->_list);
    }

    /**
    * Gets data from a PPS
    * If there is no PPS for the index given, it will return an empty string.
    * @param integer $index    The index for the PPS
    * @param integer $position The position from which to start reading
    *                          (relative to the PPS)
    * @param integer $length   The amount of bytes to read (at most)
    * @return string The binary string containing the data requested
    * @access public
    * @see OLE_PPS_File::getStream()
    */
    function getData($index, $position, $length)
    {
        // if position is not valid return empty string
        if (!isset($this->_list[$index]) ||
            $position >= $this->_list[$index]->Size ||
            $position < 0) {

            return '';
        }
        $fh = $this->getStream($this->_list[$index]);
        $data = stream_get_contents($fh, $length, $position);
        fclose($fh);
        return $data;
    }

    /**
    * Gets the data length from a PPS
    * If there is no PPS for the index given, it will return 0.
    * @param integer $index The index for the PPS
    * @return integer The amount of bytes in data the PPS has
    * @access public
    */
    function getDataLength($index)
    {
        if (isset($this->_list[$index])) {
            return $this->_list[$index]->Size;
        }
        return 0;
    }

    /**
    * Utility function to transform ASCII text to Unicode
    *
    * @access public
    * @static
    * @param string $ascii The ASCII string to transform
    * @return string The string in Unicode
    */
    function Asc2Ucs($ascii)
    {
        $rawname = '';
        for ($i = 0; $i < strlen($ascii); $i++) {
            $rawname .= $ascii{$i} . "\x00";
        }
        return $rawname;
    }

    /**
    * Utility function
    * Returns a string for the OLE container with the date given
    *
    * @access public
    * @static
    * @param integer $date A timestamp 
    * @return string The string for the OLE container
    */
    function LocalDate2OLE($date = null)
    {
        if (!isset($date)) {
            return "\x00\x00\x00\x00\x00\x00\x00\x00";
        }

        // factor used for separating numbers into 4 bytes parts
        $factor = pow(2, 32);

        // days from 1-1-1601 until the beggining of UNIX era
        $days = 134774;
        // calculate seconds
        $big_date = $days * 24 * 3600 +
            gmmktime(date("H",$date),date("i",$date),date("s",$date),
                     date("m",$date),date("d",$date),date("Y",$date));
        // multiply just to make MS happy
        $big_date *= 10000000;

        $high_part = floor($big_date / $factor);
        // lower 4 bytes
        $low_part = floor((($big_date / $factor) - $high_part) * $factor);

        // Make HEX string
        $res = '';

        for ($i = 0; $i < 4; $i++) {
            $hex = $low_part % 0x100;
            $res .= pack('c', $hex);
            $low_part /= 0x100;
        }
        for ($i = 0; $i < 4; $i++) {
            $hex = $high_part % 0x100;
            $res .= pack('c', $hex);
            $high_part /= 0x100;
        }
        return $res;
    }

    /**
    * Returns a timestamp from an OLE container's date
    * @param integer $string A binary string with the encoded date
    * @return string The timestamp corresponding to the string
    * @access public
    * @static
    */
    function OLE2LocalDate($string)
    {
        if (strlen($string) != 8) {
            return new PEAR_Error("Expecting 8 byte string");
        }

        // factor used for separating numbers into 4 bytes parts
        $factor = pow(2,32);
        $high_part = 0;
        for ($i = 0; $i < 4; $i++) {
            list(, $high_part) = unpack('C', $string{(7 - $i)});
            if ($i < 3) {
                $high_part *= 0x100;
            }
        }
        $low_part = 0;
        for ($i = 4; $i < 8; $i++) {
            list(, $low_part) = unpack('C', $string{(7 - $i)});
            if ($i < 7) {
                $low_part *= 0x100;
            }
        }
        $big_date = ($high_part * $factor) + $low_part;
        // translate to seconds
        $big_date /= 10000000;
        
        // days from 1-1-1601 until the beggining of UNIX era
        $days = 134774;
        
        // translate to seconds from beggining of UNIX era
        $big_date -= $days * 24 * 3600;
        return floor($big_date);
    }
}
?>