/code/php/functions/gunzip.php

<?php



function gunzip($file,$path='./') {

	//$path=realpath($path);

	if (!file_exists($file)) { user_error("'$file' does not exist."); return; }

	if (!is_writable($path)) { user_error("'$path' is not writable."); return; }

	if (!function_exists('gzopen')) { user_error("gzopen() function does not exist."); return; }

	

	$tar = new ArchiveTar($file);

	$contentList = $tar->getContentList();

	if (!count($contentList)) {

		user_error("Can not unpack '$file'. File is corrupt.");

		return;

	}

	//print_r($contentList); //debug

	

  $status=1;

	foreach ($contentList as $file) {

		if ($file['type'] != 'folder') {

		  if (!is_dir(dirname($path.$file['filename']))) {

		    $status=rmkdir(dirname($path.$file['filename']));

      }

			$status=$tar->extract($file['index'], $path.$file['filename']);

		}

		if (!$status) { return $status; }

	}



	$tar->close();

	return $status;

}



/**

 * Opens tar or tar.gz archives.

 * 

 * $tar = new ArchiveTar('archive.tar');

 * $contentList = $tar->getContentList();

 * foreach ($contentList as $key => $val) {

 * 	$tar->extract($key, DESTINATION);

 * }

 */

class ArchiveTar {

	protected $archiveName = '';

	protected $contentList = array();

	protected $opened = false;

	protected $read = false;

	protected $file = null;

	protected $isZipped = false;

	protected $mode = 'rb';

	

	/**

	 * Creates a new ArchiveTar object.

	 * archiveName must be tarball or gzipped tarball

	 * 

	 * @param 	string 		$archiveName

	 */

	public function __construct($archiveName) {

		$match = array();

		if (!is_file($archiveName)) {

			user_error("unable to find tar archive '".$archiveName."'");

		}

		

		$this->archiveName = $archiveName;

		$this->open();

		$this->readContent();

	}

	

	/**

	 * Destructor of this class, closes tar archive.

	 */

	public function __destruct() {

		$this->close();

	}

	

	/**

	 * Opens the tar archive and stores filehandle.

	 */

	public function open() {

		if (!$this->opened) {

			if ($this->isZipped) $this->file = new ArchiveZipFile($this->archiveName, $this->mode);

			else {

				// test compression

				$this->file = new ArchiveFile($this->archiveName, $this->mode);

				if ($this->file->read(2) == "\37\213") {

					$this->file->close();

					$this->isZipped = true;

					$this->file = new ArchiveZipFile($this->archiveName, $this->mode);

				}

				else {

					$this->file->seek(0);

				}

			}

			$this->opened = true;

		}

	}



	/**

	 * Closes the opened file.

	 */

	public function close() {

		if ($this->opened) {

			$this->file->close();

			$this->opened = false;

		}

	}

	

	/** 

	 * Returns the table of contents (TOC) list for this tar archive.

	 * 

	 * @return 	array 		list of content

	 */

	public function getContentList() {

		if (!$this->read) {

			$this->open();

			$this->readContent();

		}

		return $this->contentList;

	}

	

	/**

	 * Returns an associative array with information

	 * about a specific file in the archive.

	 *

	 * @param 	mixed 	$fileindex	index or name of the requested file

	 * @return 	array 	$fileInfo

	 */

	public function getFileInfo($fileIndex) {

		if (!is_int($fileIndex)) {

			$fileIndex = $this->getIndexByFilename($fileIndex);

		}

		

		if (!isset($this->contentList[$fileIndex])) {

			user_error("Tar: could find file '$index' in archive");

		}

		return $this->contentList[$fileIndex];

	}

	

	/**

	 * Searchs a file in the tar archive

	 * and returns the numeric fileindex.

	 * Returns false if not found.

	 *

	 * @param 	string 		$filename

	 * @return 	integer 			index of the requested file

	 */

	public function getIndexByFilename($filename) {

		foreach ($this->contentList as $index => $file) {

			if ($file['filename'] == $filename) {

				return $index;

			}

		}

		return false;

	}

	

	/**

	 * Extracts a specific file and returns the content as string.

	 * Returns false if extraction failed.

	 * 

	 * @param 	mixed 		$index		index or name of the requested file

	 * @return 	string 				content of the requested file

	 */

	public function extractToString($index) {

		if (!$this->read) {

			$this->open();

			$this->readContent();

		}

		$header = $this->getFileInfo($index);

		

		// can not extract a folder

		if ($header['type'] != 'file') {

			return false;

		}

		

		// seek to offset

		$this->file->seek($header['offset']);

		

		// read data

		$content = '';

		$n = floor($header['size'] / 512);

		for($i = 0; $i < $n; $i++) {

			$content .= $this->file->read(512);

		}

		if(($header['size'] % 512) != 0) {

			$buffer = $this->file->read(512);

			$content .= substr($buffer, 0, ($header['size'] % 512));

		}

		

		return $content;

	}

	

	/**

	 * Extracts a specific file and writes it's content

	 * to the file specified with $destination.

	 * 

	 * @param 	mixed 		$index		index or name of the requested file

	 * @param 	string 		$destination

	 * @return 	boolean 	$success

	 */

	public function extract($index, $destination) {

		if (!$this->read) {

			$this->open();

			$this->readContent();

		}

		$header = $this->getFileInfo($index);

		

		// can not extract a folder

		if ($header['type'] != 'file') {

			return false;

		}

		

		// seek to offset

		$this->file->seek($header['offset']);

		

		$targetFile = new ArchiveFile($destination);

		

		// read data

		$n = floor($header['size'] / 512);

		for ($i = 0; $i < $n; $i++) {

			$content = $this->file->read(512);

			$targetFile->write($content, 512);

		}

		if (($header['size'] % 512) != 0) {

			$content = $this->file->read(512);

			$targetFile->write($content, ($header['size'] % 512));

		}

		

		$targetFile->close();

		if (function_exists('apache_get_version') || !@$targetFile->is_writable()) {

			@$targetFile->chmod(0777);

		}

		else {

			@$targetFile->chmod(0755);

		}	

		

		if ($header['mtime']) {

			@$targetFile->touch($header['mtime']);

		}

		

		// check filesize

		if (filesize($destination) != $header['size']) {

			user_error("Could not untar file '".$header['filename']."' to '".$destination."'. Maybe disk quota exceeded in folder '".dirname($destination)."'.");

		}

		

		return true;

	}	

	

	/**

	 * Reads table of contents (TOC) from tar archive.

	 * This does not get the entire to memory but only parts of it.

	 */

	protected function readContent() {

		$this->contentList = array();

		$this->read = true;

		$i = 0;

		

		// Read the 512 bytes header

		while (strlen($binaryData = $this->file->read(512)) != 0) {

			// read header

			$header = $this->readHeader($binaryData);

			if ($header === false) {

				continue;	

			}

			$this->contentList[$i] = $header;

			$this->contentList[$i]['index'] = $i;

			$i++;

			

			$this->file->seek($this->file->tell() + (512 * ceil(($header['size'] / 512))));

		}

	}

	

	/**

	 * Unpacks file header for one file entry.

	 *

	 * @param 	string 		$binaryData

	 * @return 	array 		$fileheader

	 */

	protected function readHeader($binaryData) {

		if (strlen($binaryData) != 512) {

			return false;	

		}



		$header = array();

		$checksum = 0;

		// First part of the header

		for ($i = 0; $i < 148; $i++) {

			$checksum += ord(substr($binaryData, $i, 1));

		}

		// Calculate the checksum

		// Ignore the checksum value and replace it by ' ' (space)

		for ($i = 148; $i < 156; $i++) {

			$checksum += ord(' ');

		}

		// Last part of the header

		for ($i = 156; $i < 512; $i++) {

			$checksum += ord(substr($binaryData, $i, 1));

		}



		// Extract the values

		$data = unpack("a100filename/a8mode/a8uid/a8gid/a12size/a12mtime/a8checksum/a1typeflag/a100link/a6magic/a2version/a32uname/a32gname/a8devmajor/a8devminor/a155prefix", $binaryData);

		

		// Extract the properties

		$header['checksum'] = octDec(trim($data['checksum']));

		if ($header['checksum'] == $checksum) {

			$header['filename'] = trim($data['filename']);

			$header['mode'] = octDec(trim($data['mode']));

			$header['uid'] = octDec(trim($data['uid']));

			$header['gid'] = octDec(trim($data['gid']));

			$header['size'] = octDec(trim($data['size']));

			$header['mtime'] = octDec(trim($data['mtime']));

			$header['prefix'] = trim($data['prefix']);

			if ($header['prefix']) {

				$header['filename'] = $header['prefix'].'/'.$header['filename'];

			}

			if (($header['typeflag'] = $data['typeflag']) == '5') {

				$header['size'] = 0;

				$header['type'] = 'folder';

			}

			else {

				$header['type'] = 'file';

			}

			$header['offset'] = $this->file->tell();

			

			return $header;

		}

		else {

			return false;

		}

	}

}

/**

 * The File class handles all file operations.

 * 

 * Example:

 * using php functions:

 * $fp = fopen('filename', 'wb');

 * fwrite($fp, '...');

 * fclose($fp);

 * 

 * using this class:

 * $file = new ArchiveFile('filename');

 * $file->write('...');

 * $file->close();

 */

class ArchiveFile {

	protected $resource = null;

	protected $filename;

	

	/**

	 * Opens a new file.

	 * 

	 * @param 	string		$filename

	 * @param 	string		$mode

	 */

	public function __construct($filename, $mode = 'wb') {

		$this->filename = $filename;

		$this->resource = fopen($filename, $mode);

		if ($this->resource === false) {

			user_error('Can not open file ' . $filename);

		}

	}

	

	/**

	 * Calls the specified function on the open file.

	 * Do not call this function directly. Use $file->write('') instead.

	 * 

	 * @param 	string		$function

	 * @param 	array		$arguments

	 */

	public function __call($function, $arguments) {

		if (function_exists('f' . $function)) {

			array_unshift($arguments, $this->resource);

	       		return call_user_func_array('f' . $function, $arguments);

		}

		else if (function_exists($function)) {

			array_unshift($arguments, $this->filename);

	       		return call_user_func_array($function, $arguments);

		}

		else {

			user_error('Can not call file method ' . $function);

		}

	}

}



/**

 * The File class handles all file operations on a zipped file.

 * 

 */

class ArchiveZipFile extends ArchiveFile {

	/**

	 * Opens a new zipped file.

	 * 

	 * @param  	string		$filename

	 * @param 	string		$mode

	 */

	public function __construct($filename, $mode = 'wb') {

		$this->filename = $filename;

		if (!function_exists('gzopen')) {

			user_error('Can not find functions of the zlib extension');

		}

		$this->resource = @gzopen($filename, $mode);

		if ($this->resource === false) {

			user_error('Can not open file ' . $filename);

		}

	}

	

	/**

	 * Calls the specified function on the open file.

	 * 

	 * @param 	string		$function

	 * @param 	array		$arguments

	 */

	public function __call($function, $arguments) {

		if (function_exists('gz' . $function)) {

			array_unshift($arguments, $this->resource);

	       		return call_user_func_array('gz' . $function, $arguments);

		}

		else if (function_exists($function)) {

			array_unshift($arguments, $this->filename);

	       		return call_user_func_array($function, $arguments);

		}

		else {

			user_error('Can not call method ' . $function);

		}

	}

	

	/**

	 * Returns the filesize of the unzipped file

	 */

	public function getFileSize() {

		$byteBlock = 1<<14;

		$eof = $byteBlock;

		

		// the correction is for zip files that are too small 

		// to get in the first while loop 

		$correction = 1;

		while ($this->seek($eof) == 0) {

			$eof += $byteBlock;

			$correction = 0;

		}

		

		while ($byteBlock > 1) {

			$byteBlock >>= 1;

			$eof += $byteBlock * ($this->seek($eof) ? -1 : 1);

		}

		

		if ($this->seek($eof) == -1) $eof -= 1;

		

		$this->rewind();

		return $eof - $correction;

	}

}

//EOF