File Source for OLERead.php

<?php
/**
* PHPExcel
*
* Copyright (c) 2006 - 2010 PHPExcel
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* @category PHPExcel
* @package PHPExcel_Shared
* @copyright Copyright (c) 2006 - 2010 PHPExcel (http://www.codeplex.com/PHPExcel)
* @license http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt LGPL
* @version 1.7.3c, 2010-06-01
*/
define('IDENTIFIER_OLE', pack('CCCCCCCC', 0xd0, 0xcf, 0x11, 0xe0, 0xa1, 0xb1, 0x1a, 0xe1));
class PHPExcel_Shared_OLERead {
private $data = '';
// OLE identifier
const IDENTIFIER_OLE = IDENTIFIER_OLE;
// Size of a sector = 512 bytes
const BIG_BLOCK_SIZE = 0x200;
// Size of a short sector = 64 bytes
const SMALL_BLOCK_SIZE = 0x40;
// Size of a directory entry always = 128 bytes
const PROPERTY_STORAGE_BLOCK_SIZE = 0x80;
// Minimum size of a standard stream = 4096 bytes, streams smaller than this are stored as short streams
const SMALL_BLOCK_THRESHOLD = 0x1000;
// header offsets
const NUM_BIG_BLOCK_DEPOT_BLOCKS_POS = 0x2c;
const ROOT_START_BLOCK_POS = 0x30;
const SMALL_BLOCK_DEPOT_BLOCK_POS = 0x3c;
const EXTENSION_BLOCK_POS = 0x44;
const NUM_EXTENSION_BLOCK_POS = 0x48;
const BIG_BLOCK_DEPOT_BLOCKS_POS = 0x4c;
// property storage offsets (directory offsets)
const SIZE_OF_NAME_POS = 0x40;
const TYPE_POS = 0x42;
const START_BLOCK_POS = 0x74;
const SIZE_POS = 0x78;
/**
* Read the file
*
* @param $sFileName string Filename
* @throws Exception
*/
public function read($sFileName)
{
// Check if file exists and is readable
if(!is_readable($sFileName)) {
throw new Exception("Could not open " . $sFileName . " for reading! File does not exist, or it is not readable.");
}
// Get the file data
$this->data = file_get_contents($sFileName);
// Check OLE identifier
if (substr($this->data, 0, 8) != self::IDENTIFIER_OLE) {
throw new Exception('The filename ' . $sFileName . ' is not recognised as an OLE file');
}
// Total number of sectors used for the SAT
$this->numBigBlockDepotBlocks = $this->_GetInt4d($this->data, self::NUM_BIG_BLOCK_DEPOT_BLOCKS_POS);
// SecID of the first sector of the directory stream
$this->rootStartBlock = $this->_GetInt4d($this->data, self::ROOT_START_BLOCK_POS);
// SecID of the first sector of the SSAT (or -2 if not extant)
$this->sbdStartBlock = $this->_GetInt4d($this->data, self::SMALL_BLOCK_DEPOT_BLOCK_POS);
// SecID of the first sector of the MSAT (or -2 if no additional sectors are used)
$this->extensionBlock = $this->_GetInt4d($this->data, self::EXTENSION_BLOCK_POS);
// Total number of sectors used by MSAT
$this->numExtensionBlocks = $this->_GetInt4d($this->data, self::NUM_EXTENSION_BLOCK_POS);
$bigBlockDepotBlocks = array();
$pos = self::BIG_BLOCK_DEPOT_BLOCKS_POS;
$bbdBlocks = $this->numBigBlockDepotBlocks;
if ($this->numExtensionBlocks != 0) {
$bbdBlocks = (self::BIG_BLOCK_SIZE - self::BIG_BLOCK_DEPOT_BLOCKS_POS)/4;
}
for ($i = 0; $i < $bbdBlocks; ++$i) {
$bigBlockDepotBlocks[$i] = $this->_GetInt4d($this->data, $pos);
$pos += 4;
}
for ($j = 0; $j < $this->numExtensionBlocks; ++$j) {
$pos = ($this->extensionBlock + 1) * self::BIG_BLOCK_SIZE;
$blocksToRead = min($this->numBigBlockDepotBlocks - $bbdBlocks, self::BIG_BLOCK_SIZE / 4 - 1);
for ($i = $bbdBlocks; $i < $bbdBlocks + $blocksToRead; ++$i) {
$bigBlockDepotBlocks[$i] = $this->_GetInt4d($this->data, $pos);
$pos += 4;
}
$bbdBlocks += $blocksToRead;
if ($bbdBlocks < $this->numBigBlockDepotBlocks) {
$this->extensionBlock = $this->_GetInt4d($this->data, $pos);
}
}
$pos = 0;
$index = 0;
$this->bigBlockChain = array();
for ($i = 0; $i < $this->numBigBlockDepotBlocks; ++$i) {
$pos = ($bigBlockDepotBlocks[$i] + 1) * self::BIG_BLOCK_SIZE;
for ($j = 0 ; $j < self::BIG_BLOCK_SIZE / 4; ++$j) {
$this->bigBlockChain[$index] = $this->_GetInt4d($this->data, $pos);
$pos += 4 ;
++$index;
}
}
$pos = 0;
$index = 0;
$sbdBlock = $this->sbdStartBlock;
$this->smallBlockChain = array();
while ($sbdBlock != -2) {
$pos = ($sbdBlock + 1) * self::BIG_BLOCK_SIZE;
for ($j = 0; $j < self::BIG_BLOCK_SIZE / 4; ++$j) {
$this->smallBlockChain[$index] = $this->_GetInt4d($this->data, $pos);
$pos += 4;
++$index;
}
$sbdBlock = $this->bigBlockChain[$sbdBlock];
}
$block = $this->rootStartBlock;
$pos = 0;
// read the directory stream
$this->entry = $this->_readData($block);
$this->_readPropertySets();
}
/**
* Extract binary stream data, workbook stream + sheet streams
*
* @return string
*/
public function getWorkBook()
{
if ($this->props[$this->wrkbook]['size'] < self::SMALL_BLOCK_THRESHOLD){
$rootdata = $this->_readData($this->props[$this->rootentry]['startBlock']);
$streamData = '';
$block = $this->props[$this->wrkbook]['startBlock'];
$pos = 0;
while ($block != -2) {
$pos = $block * self::SMALL_BLOCK_SIZE;
$streamData .= substr($rootdata, $pos, self::SMALL_BLOCK_SIZE);
$block = $this->smallBlockChain[$block];
}
return $streamData;
} else {
$numBlocks = $this->props[$this->wrkbook]['size'] / self::BIG_BLOCK_SIZE;
if ($this->props[$this->wrkbook]['size'] % self::BIG_BLOCK_SIZE != 0) {
++$numBlocks;
}
if ($numBlocks == 0) return '';
$streamData = '';
$block = $this->props[$this->wrkbook]['startBlock'];
$pos = 0;
while ($block != -2) {
$pos = ($block + 1) * self::BIG_BLOCK_SIZE;
$streamData .= substr($this->data, $pos, self::BIG_BLOCK_SIZE);
$block = $this->bigBlockChain[$block];
}
return $streamData;
}
}
/**
* Extract binary stream data, summary information
*
* @return string|null
*/
public function getSummaryInformation()
{
if (!isset($this->summaryInformation)) {
return null;
}
if ($this->props[$this->summaryInformation]['size'] < self::SMALL_BLOCK_THRESHOLD){
$rootdata = $this->_readData($this->props[$this->rootentry]['startBlock']);
$streamData = '';
$block = $this->props[$this->summaryInformation]['startBlock'];
$pos = 0;
while ($block != -2) {
$pos = $block * self::SMALL_BLOCK_SIZE;
$streamData .= substr($rootdata, $pos, self::SMALL_BLOCK_SIZE);
$block = $this->smallBlockChain[$block];
}
return $streamData;
} else {
$numBlocks = $this->props[$this->summaryInformation]['size'] / self::BIG_BLOCK_SIZE;
if ($this->props[$this->summaryInformation]['size'] % self::BIG_BLOCK_SIZE != 0) {
++$numBlocks;
}
if ($numBlocks == 0) return '';
$streamData = '';
$block = $this->props[$this->summaryInformation]['startBlock'];
$pos = 0;
while ($block != -2) {
$pos = ($block + 1) * self::BIG_BLOCK_SIZE;
$streamData .= substr($this->data, $pos, self::BIG_BLOCK_SIZE);
$block = $this->bigBlockChain[$block];
}
return $streamData;
}
}
/**
* Read a standard stream (by joining sectors using information from SAT)
*
* @param int $bl Sector ID where the stream starts
* @return string Data for standard stream
*/
private function _readData($bl)
{
$block = $bl;
$pos = 0;
$data = '';
while ($block != -2) {
$pos = ($block + 1) * self::BIG_BLOCK_SIZE;
$data = $data . substr($this->data, $pos, self::BIG_BLOCK_SIZE);
$block = $this->bigBlockChain[$block];
}
return $data;
}
/**
* Read entries in the directory stream.
*/
private function _readPropertySets()
{
$offset = 0;
// loop through entires, each entry is 128 bytes
while ($offset < strlen($this->entry)) {
// entry data (128 bytes)
$d = substr($this->entry, $offset, self::PROPERTY_STORAGE_BLOCK_SIZE);
// size in bytes of name
$nameSize = ord($d[self::SIZE_OF_NAME_POS]) | (ord($d[self::SIZE_OF_NAME_POS+1]) << 8);
// type of entry
$type = ord($d[self::TYPE_POS]);
// sectorID of first sector or short sector, if this entry refers to a stream (the case with workbook)
// sectorID of first sector of the short-stream container stream, if this entry is root entry
$startBlock = $this->_GetInt4d($d, self::START_BLOCK_POS);
$size = $this->_GetInt4d($d, self::SIZE_POS);
$name = '';
for ($i = 0; $i < $nameSize ; ++$i) {
$name .= $d[$i];
}
$name = str_replace("\x00", "", $name);
$this->props[] = array (
'name' => $name,
'type' => $type,
'startBlock' => $startBlock,
'size' => $size);
// Workbook directory entry (BIFF5 uses Book, BIFF8 uses Workbook)
if (($name == 'Workbook') || ($name == 'Book') || ($name == 'WORKBOOK') || ($name == 'BOOK')) {
$this->wrkbook = count($this->props) - 1;
}
// Root entry
if ($name == 'Root Entry' || $name == 'ROOT ENTRY' || $name == 'R') {
$this->rootentry = count($this->props) - 1;
}
// Summary information
if ($name == chr(5) . 'SummaryInformation') {
$this->summaryInformation = count($this->props) - 1;
}
$offset += self::PROPERTY_STORAGE_BLOCK_SIZE;
}
}
/**
* Read 4 bytes of data at specified position
*
* @param string $data
* @param int $pos
* @return int
*/
private function _GetInt4d($data, $pos)
{
// Hacked by Andreas Rehm 2006 to ensure correct result of the <<24 block on 32 and 64bit systems
$_or_24 = ord($data[$pos+3]);
if ($_or_24>=128) $_ord_24 = -abs((256-$_or_24) << 24);
else $_ord_24 = ($_or_24&127) << 24;
return ord($data[$pos]) | (ord($data[$pos+1]) << 8) | (ord($data[$pos+2]) << 16) | $_ord_24;
}
}

Source for file OLERead.php