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<?php
/**
* Akeeba Engine
* The modular PHP5 site backup engine
*
* @copyright Copyright (c)2006-2016 Nicholas K. Dionysopoulos
* @license GNU GPL version 3 or, at your option, any later version
* @package akeebaengine
*
*/
namespace Akeeba\Engine\Archiver;
// Protection against direct access
defined('AKEEBAENGINE') or die();
use Akeeba\Engine\Base\Object as BaseObject;
use Akeeba\Engine\Factory;
use Akeeba\Engine\Platform;
use Akeeba\Engine\Util\Filesystem;
use Psr\Log\LogLevel;
if ( !defined('AKEEBA_CHUNK'))
{
$configuration = Factory::getConfiguration();
$chunksize = $configuration->get('engine.archiver.common.chunk_size', 1048756);
define('AKEEBA_CHUNK', $chunksize);
}
/**
* Abstract parent class of all archiver engines
*/
abstract class Base extends BaseObject
{
/** @var resource JPA transformation source handle */
private $_xform_fp;
/** @var string The archive's comment. It's currently used ONLY in the ZIP file format */
protected $_comment;
/** @var array The last part which has been finalized and waits to be post-processed */
public $finishedPart = array();
/** @var array An array of open file pointers */
private $filePointers = array();
/** @var array An array of the last open files for writing and their last written to offsets */
private $fileOffsets = array();
/** @var resource File pointer to the archive being currently written to */
protected $fp = null;
/** @var resource File pointer to the archive's central directory file (for ZIP) */
protected $cdfp = null;
/** @var Filesystem Filesystem utilities object */
protected $fsUtils = null;
/**
* Common code which gets called on instance creation or wake-up (unserialization)
*
* @codeCoverageIgnore
*
* @return void
*/
protected function __bootstrap_code()
{
if ( !defined('AKEEBA_CHUNK'))
{
// Cache chunk override as a constant
$registry = Factory::getConfiguration();
$chunk_override = $registry->get('engine.archiver.common.chunk_size', 0);
define('AKEEBA_CHUNK', $chunk_override > 0 ? $chunk_override : 1048756);
}
$this->fsUtils = Factory::getFilesystemTools();
}
/**
* Public constructor
*
* @codeCoverageIgnore
*
* @return Base
*/
public function __construct()
{
$this->__bootstrap_code();
}
/**
* Wakeup (unserialization) function
*
* @codeCoverageIgnore
*
* @return void
*/
public function __wakeup()
{
$this->__bootstrap_code();
}
/**
* Release file pointers when the object is being serialized
*
* @codeCoverageIgnore
*
* @return void
*/
public function _onSerialize()
{
$this->_closeAllFiles();
$this->fp = null;
$this->cdfp = null;
parent::_onSerialize();
}
/**
* Release file pointers when the object is being destroyed
*
* @codeCoverageIgnore
*
* @return void
*/
public function __destruct()
{
$this->_closeAllFiles();
$this->fp = null;
$this->cdfp = null;
}
/**
* Overrides setError() in order to also write the error message to the log file
*
* @param string $error The error message
*
* @codeCoverageIgnore
*
* @return void
*/
public function setError($error)
{
parent::setError($error);
Factory::getLog()->log(LogLevel::ERROR, $error);
}
/**
* Overrides setWarning() in order to also write the warning message to the log file
*
* @param string $warning The warning message
*
* @codeCoverageIgnore
*
* @return void
*/
public function setWarning($warning)
{
parent::setWarning($warning);
Factory::getLog()->log(LogLevel::WARNING, $warning);
}
/**
* Notifies the engine on the backup comment and converts it to plain text for
* inclusion in the archive file, if applicable.
*
* @param string $comment The archive's comment
*
* @return void
*/
public function setComment($comment)
{
// First, sanitize the comment in a text-only format
$comment = str_replace("\n", " ", $comment); // Replace newlines with spaces
$comment = str_replace("<br>", "\n", $comment); // Replace HTML4 <br> with single newlines
$comment = str_replace("<br/>", "\n", $comment); // Replace HTML4 <br> with single newlines
$comment = str_replace("<br />", "\n", $comment); // Replace HTML <br /> with single newlines
$comment = str_replace("</p>", "\n\n", $comment); // Replace paragraph endings with double newlines
$comment = str_replace("<b>", "*", $comment); // Replace bold with star notation
$comment = str_replace("</b>", "*", $comment); // Replace bold with star notation
$comment = str_replace("<i>", "_", $comment); // Replace italics with underline notation
$comment = str_replace("</i>", "_", $comment); // Replace italics with underline notation
$this->_comment = strip_tags($comment, '');
}
/**
* Adds a list of files into the archive, removing $removePath from the
* file names and adding $addPath to them.
*
* @param array $fileList A simple string array of filepaths to include
* @param string $removePath Paths to remove from the filepaths
* @param string $addPath Paths to add in front of the filepaths
*
* @return boolean True on success
*/
public function addFileList(&$fileList, $removePath = '', $addPath = '')
{
if ( !is_array($fileList))
{
$this->setWarning('addFileList called without a file list array');
return false;
}
// @codeCoverageIgnoreStart
if (function_exists('mb_internal_encoding'))
{
$mb_encoding = mb_internal_encoding();
mb_internal_encoding('ISO-8859-1');
}
// @codeCoverageIgnoreEnd
foreach ($fileList as $file)
{
$storedName = $this->_addRemovePaths($file, $removePath, $addPath);
$ret = $this->_addFile(false, $file, $storedName);
}
// @codeCoverageIgnoreStart
if (function_exists('mb_internal_encoding'))
{
mb_internal_encoding($mb_encoding);
}
// @codeCoverageIgnoreEnd
return true;
}
/**
* Adds a single file in the archive
*
* @param string $file The absolute path to the file to add
* @param string $removePath Path to remove from $file
* @param string $addPath Path to prepend to $file
*
* @return boolean
*/
public function addFile($file, $removePath = '', $addPath = '')
{
if (function_exists('mb_internal_encoding'))
{
$mb_encoding = mb_internal_encoding();
mb_internal_encoding('ISO-8859-1');
}
$storedName = $this->_addRemovePaths($file, $removePath, $addPath);
$ret = $this->_addFile(false, $file, $storedName);
if (function_exists('mb_internal_encoding'))
{
mb_internal_encoding($mb_encoding);
}
return $ret;
}
/**
* Adds a file to the archive, with a name that's different from the source
* filename
*
* @param string $sourceFile Absolute path to the source file
* @param string $targetFile Relative filename to store in archive
*
* @return boolean
*/
public function addFileRenamed($sourceFile, $targetFile)
{
if (function_exists('mb_internal_encoding'))
{
$mb_encoding = mb_internal_encoding();
mb_internal_encoding('ISO-8859-1');
}
$ret = $this->_addFile(false, $sourceFile, $targetFile);
if (function_exists('mb_internal_encoding'))
{
mb_internal_encoding($mb_encoding);
}
return $ret;
}
/**
* Adds a file to the archive, given the stored name and its contents
*
* @param string $fileName The base file name
* @param string $addPath The relative path to prepend to file name
* @param string $virtualContent The contents of the file to be archived
*
* @return boolean
*/
public function addVirtualFile($fileName, $addPath = '', &$virtualContent)
{
$storedName = $this->_addRemovePaths($fileName, '', $addPath);
if (function_exists('mb_internal_encoding'))
{
$mb_encoding = mb_internal_encoding();
mb_internal_encoding('ISO-8859-1');
}
$ret = $this->_addFile(true, $virtualContent, $storedName);
if (function_exists('mb_internal_encoding'))
{
mb_internal_encoding($mb_encoding);
}
return $ret;
}
/**
* Initialises the archiver class, creating the archive from an existent
* installer's JPA archive. MUST BE OVERRIDEN BY CHILDREN CLASSES.
*
* @param string $targetArchivePath Absolute path to the generated archive
* @param array $options A named key array of options (optional)
*
* @return void
*/
abstract public function initialize($targetArchivePath, $options = array());
/**
* Makes whatever finalization is needed for the archive to be considered
* complete and useful (or, generally, clean up)
*
* @return void
*/
public function finalize()
{
}
/**
* Returns a string with the extension (including the dot) of the files produced
* by this class.
*
* @return string
*/
abstract public function getExtension();
/**
* The most basic file transaction: add a single entry (file or directory) to
* the archive.
*
* @param boolean $isVirtual If true, the next parameter contains file data instead of a file name
* @param string $sourceNameOrData Absolute file name to read data from or the file data itself is $isVirtual is
* true
* @param string $targetName The (relative) file name under which to store the file in the archive
*
* @return boolean True on success, false otherwise
*/
abstract protected function _addFile($isVirtual, &$sourceNameOrData, $targetName);
/**
* Opens a file, if it's not already open, or returns its cached file pointer if it's already open
*
* @param string $file The filename to open
* @param string $mode File open mode, defaults to binary write
*
* @return resource
*/
protected function _fopen($file, $mode = 'wb')
{
if ( !array_key_exists($file, $this->filePointers))
{
//Factory::getLog()->log(LogLevel::DEBUG, "Opening backup archive $file with mode $mode");
$this->filePointers[$file] = @fopen($file, $mode);
// If we open a file for append we have to seek to the correct offset
if (substr($mode, 0, 1) == 'a')
{
if (isset($this->fileOffsets[$file]))
{
//Factory::getLog()->log(LogLevel::DEBUG, "Truncating to " . $this->fileOffsets[$file]);
@ftruncate($this->filePointers[$file], $this->fileOffsets[$file]);
}
fseek($this->filePointers[$file], 0, SEEK_END);
}
}
return $this->filePointers[$file];
}
/**
* Closes an already open file
*
* @param resource $fp The file pointer to close
*
* @return boolean
*/
protected function _fclose(&$fp)
{
$offset = array_search($fp, $this->filePointers, true);
$result = @fclose($fp);
if ($offset !== false)
{
unset($this->filePointers[$offset]);
}
$fp = null;
return $result;
}
/**
* Closes all open files known to this archiver object
*
* @return void
*/
protected function _closeAllFiles()
{
if ( !empty($this->filePointers))
{
foreach ($this->filePointers as $file => $fp)
{
@fclose($fp);
unset($this->filePointers[$file]);
}
}
}
/**
* Write to file, defeating magic_quotes_runtime settings (pure binary write)
*
* @param resource $fp Handle to a file
* @param string $data The data to write to the file
* @param integer $p_len Maximum length of data to write
*
* @return boolean
*/
protected function _fwrite($fp, $data, $p_len = null)
{
static $lastFp = null;
static $filename = null;
if ($fp !== $lastFp)
{
$lastFp = $fp;
$filename = array_search($fp, $this->filePointers, true);
}
$len = is_null($p_len) ? (function_exists('mb_strlen') ? mb_strlen($data, '8bit') : strlen($data)) : $p_len;
$ret = fwrite($fp, $data, $len);
if (($ret === false) || (abs(($ret - $len)) >= 1))
{
// Log debug information about the archive file's existence and current size. This helps us figure out if
// there is a server-imposed maximum file size limit.
clearstatcache();
$fileExists = @file_exists($filename) ? 'exists' : 'does NOT exist';
$currentSize = @filesize($filename);
Factory::getLog()->log(LogLevel::DEBUG, __CLASS__ . "::_fwrite() ERROR!! Cannot write to archive file $filename. The file $fileExists. File size $currentSize bytes after writing $ret of $len bytes. Please check the output directory permissions and make sure you have enough disk space available. If this does not help, please set up a Part Size for Split Archives LOWER than this size and retry backing up.");
$this->setError('Couldn\'t write to the archive file; check the output directory permissions and make sure you have enough disk space available.' . "[len=$ret / $len]");
return false;
}
if ($filename !== false)
{
$this->fileOffsets[$filename] = @ftell($fp);
}
return true;
}
/**
* Removes a file path from the list of resumable offsets
*
* @param $filename
*/
protected function _removeFromOffsetsList($filename)
{
if (isset($this->fileOffsets[$filename]))
{
unset($this->fileOffsets[$filename]);
}
}
/**
* Converts a human formatted size to integer representation of bytes,
* e.g. 1M to 1024768
*
* @param string $val The value in human readable format, e.g. "1M"
*
* @return integer The value in bytes
*/
protected function _return_bytes($val)
{
$val = trim($val);
$last = strtolower($val{strlen($val) - 1});
switch ($last)
{
// The 'G' modifier is available since PHP 5.1.0
case 'g':
$val *= 1024;
case 'm':
$val *= 1024;
case 'k':
$val *= 1024;
}
return $val;
}
/**
* Removes the $p_remove_dir from $p_filename, while prepending it with $p_add_dir.
* Largely based on code from the pclZip library.
*
* @param string $p_filename The absolute file name to treat
* @param string $p_remove_dir The path to remove
* @param string $p_add_dir The path to prefix the treated file name with
*
* @return string The treated file name
*/
protected function _addRemovePaths($p_filename, $p_remove_dir, $p_add_dir)
{
$p_filename = $this->fsUtils->TranslateWinPath($p_filename);
$p_remove_dir = ($p_remove_dir == '') ? '' : $this->fsUtils->TranslateWinPath($p_remove_dir); //should fix corrupt backups, fix by nicholas
$v_stored_filename = $p_filename;
if ( !($p_remove_dir == ""))
{
if (substr($p_remove_dir, -1) != '/')
{
$p_remove_dir .= "/";
}
if ((substr($p_filename, 0, 2) == "./") || (substr($p_remove_dir, 0, 2) == "./"))
{
if ((substr($p_filename, 0, 2) == "./") && (substr($p_remove_dir, 0, 2) != "./"))
{
$p_remove_dir = "./" . $p_remove_dir;
}
if ((substr($p_filename, 0, 2) != "./") && (substr($p_remove_dir, 0, 2) == "./"))
{
$p_remove_dir = substr($p_remove_dir, 2);
}
}
$v_compare = $this->_PathInclusion($p_remove_dir, $p_filename);
if ($v_compare > 0)
{
if ($v_compare == 2)
{
$v_stored_filename = "";
}
else
{
$v_stored_filename = substr($p_filename, (function_exists('mb_strlen') ? mb_strlen($p_remove_dir, '8bit') : strlen($p_remove_dir)));
}
}
}
else
{
$v_stored_filename = $p_filename;
}
if ( !($p_add_dir == ""))
{
if (substr($p_add_dir, -1) == "/")
{
$v_stored_filename = $p_add_dir . $v_stored_filename;
}
else
{
$v_stored_filename = $p_add_dir . "/" . $v_stored_filename;
}
}
return $v_stored_filename;
}
/**
* This function indicates if the path $p_path is under the $p_dir tree. Or,
* said in an other way, if the file or sub-dir $p_path is inside the dir
* $p_dir.
* The function indicates also if the path is exactly the same as the dir.
* This function supports path with duplicated '/' like '//', but does not
* support '.' or '..' statements.
*
* Copied verbatim from pclZip library
*
* @codeCoverageIgnore
*
* @param string $p_dir Source tree
* @param string $p_path Check if this is part of $p_dir
*
* @return integer 0 if $p_path is not inside directory $p_dir,
* 1 if $p_path is inside directory $p_dir
* 2 if $p_path is exactly the same as $p_dir
*/
protected function _PathInclusion($p_dir, $p_path)
{
$v_result = 1;
// ----- Explode dir and path by directory separator
$v_list_dir = explode("/", $p_dir);
$v_list_dir_size = sizeof($v_list_dir);
$v_list_path = explode("/", $p_path);
$v_list_path_size = sizeof($v_list_path);
// ----- Study directories paths
$i = 0;
$j = 0;
while (($i < $v_list_dir_size) && ($j < $v_list_path_size) && ($v_result))
{
// ----- Look for empty dir (path reduction)
if ($v_list_dir[$i] == '')
{
$i++;
continue;
}
if ($v_list_path[$j] == '')
{
$j++;
continue;
}
// ----- Compare the items
if (($v_list_dir[$i] != $v_list_path[$j]) && ($v_list_dir[$i] != '') && ($v_list_path[$j] != ''))
{
$v_result = 0;
}
// ----- Next items
$i++;
$j++;
}
// ----- Look if everything seems to be the same
if ($v_result)
{
// ----- Skip all the empty items
while (($j < $v_list_path_size) && ($v_list_path[$j] == ''))
{
$j++;
}
while (($i < $v_list_dir_size) && ($v_list_dir[$i] == ''))
{
$i++;
}
if (($i >= $v_list_dir_size) && ($j >= $v_list_path_size))
{
// ----- There are exactly the same
$v_result = 2;
}
else if ($i < $v_list_dir_size)
{
// ----- The path is shorter than the dir
$v_result = 0;
}
}
// ----- Return
return $v_result;
}
/**
* Transforms a JPA archive (containing an installer) to the native archive format
* of the class. It actually extracts the source JPA in memory and instructs the
* class to include each extracted file.
*
* @codeCoverageIgnore
*
* @param integer $index The index in the source JPA archive's list currently in use
* @param integer $offset The source JPA archive's offset to use
*
* @return boolean False if an error occurred, true otherwise
*/
public function transformJPA($index, $offset)
{
static $totalSize = 0;
// Do we have to open the file?
if ( !$this->_xform_fp)
{
// Get the source path
$registry = Factory::getConfiguration();
$embedded_installer = $registry->get('akeeba.advanced.embedded_installer');
// Fetch the name of the installer image
$installerDescriptors = Factory::getEngineParamsProvider()->getInstallerList();
$xform_source = Platform::getInstance()->get_installer_images_path() .
'/foobar.jpa'; // We need this as a "safe fallback"
// Try to find a sane default if we are not given a valid embedded installer
if (!array_key_exists($embedded_installer, $installerDescriptors))
{
$embedded_installer = 'angie';
if (!array_key_exists($embedded_installer, $installerDescriptors))
{
$allInstallers = array_keys($installerDescriptors);
foreach ($allInstallers as $anInstaller)
{
if ($anInstaller == 'none')
{
continue;
}
$embedded_installer = $anInstaller;
break;
}
}
}
if (array_key_exists($embedded_installer, $installerDescriptors))
{
$packages = $installerDescriptors[$embedded_installer]['package'];
if (empty($packages))
{
// No installer package specified. Pretend we are done!
$retArray = array(
"filename" => '', // File name extracted
"data" => '', // File data
"index" => 0, // How many source JPA files I have
"offset" => 0, // Offset in JPA file
"skip" => false, // Skip this?
"done" => true, // Are we done yet?
"filesize" => 0
);
return $retArray;
}
$packages = explode(',', $packages);
$totalSize = 0;
$pathPrefix = Platform::getInstance()->get_installer_images_path() . '/';
foreach ($packages as $package)
{
$filePath = $pathPrefix . $package;
$totalSize += (int)@filesize($filePath);
}
if (count($packages) < $index)
{
$this->setError(__CLASS__ . ":: Installer package index $index not found for embedded installer $embedded_installer");
return false;
}
$package = $packages[$index];
// A package is specified, use it!
$xform_source = $pathPrefix . $package;
}
// 2.3: Try to use sane default if the indicated installer doesn't exist
if ( !file_exists($xform_source) && (basename($xform_source) != 'angie.jpa'))
{
$this->setError(__CLASS__ . ":: Installer package $xform_source of embedded installer $embedded_installer not found. Please go to the configuration page, select an Embedded Installer, save the configuration and try backing up again.");
return false;
}
// Try opening the file
if (file_exists($xform_source))
{
$this->_xform_fp = @fopen($xform_source, 'r');
if ($this->_xform_fp === false)
{
$this->setError(__CLASS__ . ":: Can't seed archive with installer package " . $xform_source);
return false;
}
}
else
{
$this->setError(__CLASS__ . ":: Installer package " . $xform_source . " does not exist!");
return false;
}
}
$headerDataLength = 0;
if ( !$offset)
{
// First run detected!
Factory::getLog()->log(LogLevel::DEBUG, 'Initializing with JPA package ' . $xform_source);
// Skip over the header and check no problem exists
$offset = $this->_xformReadHeader();
if ($offset === false)
{
$this->setError('JPA package file was not read');
return false; // Oops! The package file doesn't exist or is corrupt
}
$headerDataLength = $offset;
}
$ret = $this->_xformExtract($offset);
$ret['index'] = $index;
if (is_array($ret))
{
$ret['chunkProcessed'] = $headerDataLength + $ret['offset'] - $offset;
$offset = $ret['offset'];
if ( !$ret['skip'] && !$ret['done'])
{
Factory::getLog()->log(LogLevel::DEBUG, ' Adding ' . $ret['filename'] . '; Next offset:' . $offset);
$this->addVirtualFile($ret['filename'], '', $ret['data']);
if ($this->getError())
{
return false;
}
}
elseif ($ret['done'])
{
$registry = Factory::getConfiguration();
$embedded_installer = $registry->get('akeeba.advanced.embedded_installer');
$installerDescriptors = Factory::getEngineParamsProvider()->getInstallerList();
$packages = $installerDescriptors[$embedded_installer]['package'];
$packages = explode(',', $packages);
Factory::getLog()->log(LogLevel::DEBUG, ' Done with package ' . $packages[$index]);
if (count($packages) > ($index + 1))
{
$ret['done'] = false;
$ret['index'] = $index + 1;
$ret['offset'] = 0;
$this->_xform_fp = null;
}
else
{
Factory::getLog()->log(LogLevel::DEBUG, ' Done with installer seeding.');
}
}
else
{
$reason = ' Skipping ' . $ret['filename'];
Factory::getLog()->log(LogLevel::DEBUG, $reason);
}
}
else
{
$this->setError('JPA extraction returned FALSE. The installer image is corrupt.');
return false;
}
if ($ret['done'])
{
// We are finished! Close the file
fclose($this->_xform_fp);
Factory::getLog()->log(LogLevel::DEBUG, 'Initializing with JPA package has finished');
}
$ret['filesize'] = $totalSize;
return $ret;
}
/**
* Extracts a file from the JPA archive and returns an in-memory array containing it
* and its file data. The data returned is an array, consisting of the following keys:
* "filename" => relative file path stored in the archive
* "data" => file data
* "offset" => next offset to use
* "skip" => if this is not a file, just skip it...
* "done" => No more files left in archive
*
* @codeCoverageIgnore
*
* @param integer $offset The absolute data offset from archive's header
*
* @return array See description for more information
*/
protected function &_xformExtract($offset)
{
$false = false; // Used to return false values in case an error occurs
// Generate a return array
$retArray = array(
"filename" => '', // File name extracted
"data" => '', // File data
"offset" => 0, // Offset in ZIP file
"skip" => false, // Skip this?
"done" => false // Are we done yet?
);
// If we can't open the file, return an error condition
if ($this->_xform_fp === false)
{
return $false;
}
// Go to the offset specified
if ( !fseek($this->_xform_fp, $offset) == 0)
{
return $false;
}
// Get and decode Entity Description Block
$signature = fread($this->_xform_fp, 3);
// Check signature
if ($signature == 'JPF')
{
// This a JPA Entity Block. Process the header.
// Read length of EDB and of the Entity Path Data
$length_array = unpack('vblocksize/vpathsize', fread($this->_xform_fp, 4));
// Read the path data
$file = fread($this->_xform_fp, $length_array['pathsize']);
// Read and parse the known data portion
$bin_data = fread($this->_xform_fp, 14);
$header_data = unpack('Ctype/Ccompression/Vcompsize/Vuncompsize/Vperms', $bin_data);
// Read any unknwon data
$restBytes = $length_array['blocksize'] - (21 + $length_array['pathsize']);
if ($restBytes > 0)
{
$junk = fread($this->_xform_fp, $restBytes);
}
$compressionType = $header_data['compression'];
// Populate the return array
$retArray['filename'] = $file;
$retArray['skip'] = ($header_data['compsize'] == 0); // Skip over directories
switch ($header_data['type'])
{
case 0:
// directory
break;
case 1:
// file
switch ($compressionType)
{
case 0: // No compression
if ($header_data['compsize'] > 0) // 0 byte files do not have data to be read
{
$retArray['data'] = fread($this->_xform_fp, $header_data['compsize']);
}
break;
case 1: // GZip compression
$zipData = fread($this->_xform_fp, $header_data['compsize']);
$retArray['data'] = gzinflate($zipData);
break;
case 2: // BZip2 compression
$zipData = fread($this->_xform_fp, $header_data['compsize']);
$retArray['data'] = bzdecompress($zipData);
break;
}
break;
}
}
else
{
// This is not a file header. This means we are done.
$retArray['done'] = true;
}
$retArray['offset'] = ftell($this->_xform_fp);
return $retArray;
}
/**
* Skips over the JPA header entry and returns the offset file data starts from
*
* @codeCoverageIgnore
*
* @return boolean|integer False on failure, offset otherwise
*/
protected function _xformReadHeader()
{
// Fail for unreadable files
if ($this->_xform_fp === false)
{
return false;
}
// Go to the beggining of the file
rewind($this->_xform_fp);
// Read the signature
$sig = fread($this->_xform_fp, 3);
// Not a JPA Archive?
if ($sig != 'JPA')
{
return false;
}
// Read and parse header length
$header_length_array = unpack('v', fread($this->_xform_fp, 2));
$header_length = $header_length_array[1];
// Read and parse the known portion of header data (14 bytes)
$bin_data = fread($this->_xform_fp, 14);
$header_data = unpack('Cmajor/Cminor/Vcount/Vuncsize/Vcsize', $bin_data);
// Load any remaining header data (forward compatibility)
$rest_length = $header_length - 19;
if ($rest_length > 0)
{
$junk = fread($this->_xform_fp, $rest_length);
}
return ftell($this->_xform_fp);
}
}