<?php
/**
* This is a copy of DokuWiki's core tar library
*
* A copy is used because old DokuWiki installs may have an old version. It has also been adjusted to
* print each extracted file
*
* @author Andreas Gohr <andi@splitbrain.org>
* @author Bouchon <tarlib@bouchon.org> (Maxg)
* @license GPL 2
*/
class VerboseTar {
const COMPRESS_AUTO = 0;
const COMPRESS_NONE = 1;
const COMPRESS_GZIP = 2;
const COMPRESS_BZIP = 3;
protected $file = '';
protected $comptype = self::COMPRESS_AUTO;
protected $fh;
protected $memory = '';
protected $closed = true;
protected $writeaccess = false;
/**
* Open an existing TAR file for reading
*
* @param string $file
* @param int $comptype
* @throws VerboseTarIOException
*/
public function open($file, $comptype = self::COMPRESS_AUTO) {
// determine compression
if($comptype == self::COMPRESS_AUTO) $comptype = $this->filetype($file);
$this->compressioncheck($comptype);
$this->comptype = $comptype;
$this->file = $file;
if($this->comptype === self::COMPRESS_GZIP) {
$this->fh = @gzopen($this->file, 'rb');
} elseif($this->comptype === self::COMPRESS_BZIP) {
$this->fh = @bzopen($this->file, 'r');
} else {
$this->fh = @fopen($this->file, 'rb');
}
if(!$this->fh) throw new VerboseTarIOException('Could not open file for reading: '.$this->file);
$this->closed = false;
}
/**
* Read the contents of a TAR archive
*
* This function lists the files stored in the archive, and returns an indexed array of associative
* arrays containing for each file the following information:
*
* checksum Tar Checksum of the file
* filename The full name of the stored file (up to 100 c.)
* mode UNIX permissions in DECIMAL, not octal
* uid The Owner ID
* gid The Group ID
* size Uncompressed filesize
* mtime Timestamp of last modification
* typeflag Empty for files, set for folders
* link Is it a symlink?
* uname Owner name
* gname Group name
*
* The archive is closed afer reading the contents, because rewinding is not possible in bzip2 streams.
* Reopen the file with open() again if you want to do additional operations
*/
public function contents() {
if($this->closed || !$this->file) throw new VerboseTarIOException('Can not read from a closed archive');
$result = array();
while($read = $this->readbytes(512)) {
$header = $this->parseHeader($read);
if(!is_array($header)) continue;
$this->skipbytes(ceil($header['size'] / 512) * 512);
$result[] = $header;
}
$this->close();
return $result;
}
/**
* Extract an existing TAR archive
*
* The $strip parameter allows you to strip a certain number of path components from the filenames
* found in the tar file, similar to the --strip-components feature of GNU tar. This is triggered when
* an integer is passed as $strip.
* Alternatively a fixed string prefix may be passed in $strip. If the filename matches this prefix,
* the prefix will be stripped. It is recommended to give prefixes with a trailing slash.
*
* By default this will extract all files found in the archive. You can restrict the output using the $include
* and $exclude parameter. Both expect a full regular expression (including delimiters and modifiers). If
* $include is set only files that match this expression will be extracted. Files that match the $exclude
* expression will never be extracted. Both parameters can be used in combination. Expressions are matched against
* stripped filenames as described above.
*
* The archive is closed afer reading the contents, because rewinding is not possible in bzip2 streams.
* Reopen the file with open() again if you want to do additional operations
*
* @param string $outdir the target directory for extracting
* @param int|string $strip either the number of path components or a fixed prefix to strip
* @param string $exclude a regular expression of files to exclude
* @param string $include a regular expression of files to include
* @throws VerboseTarIOException
* @return array
*/
function extract($outdir, $strip = '', $exclude = '', $include = '') {
if($this->closed || !$this->file) throw new VerboseTarIOException('Can not read from a closed archive');
$outdir = rtrim($outdir, '/');
io_mkdir_p($outdir);
$striplen = strlen($strip);
$extracted = array();
while($dat = $this->readbytes(512)) {
// read the file header
$header = $this->parseHeader($dat);
if(!is_array($header)) continue;
if(!$header['filename']) continue;
// strip prefix
$filename = $this->cleanPath($header['filename']);
if(is_int($strip)) {
// if $strip is an integer we strip this many path components
$parts = explode('/', $filename);
if(!$header['typeflag']) {
$base = array_pop($parts); // keep filename itself
} else {
$base = '';
}
$filename = join('/', array_slice($parts, $strip));
if($base) $filename .= "/$base";
} else {
// ifstrip is a string, we strip a prefix here
if(substr($filename, 0, $striplen) == $strip) $filename = substr($filename, $striplen);
}
// check if this should be extracted
$extract = true;
if(!$filename) {
$extract = false;
} else {
if($include) {
if(preg_match($include, $filename)) {
$extract = true;
} else {
$extract = false;
}
}
if($exclude && preg_match($exclude, $filename)) {
$extract = false;
}
}
// Now do the extraction (or not)
if($extract) {
$extracted[] = $header;
$output = "$outdir/$filename";
$directory = ($header['typeflag']) ? $output : dirname($output);
io_mkdir_p($directory);
// print status
admin_plugin_elwikiupgrade::_say(hsc($filename));
// is this a file?
if(!$header['typeflag']) {
$fp = fopen($output, "wb");
if(!$fp) throw new VerboseTarIOException('Could not open file for writing: '.$output);
$size = floor($header['size'] / 512);
for($i = 0; $i < $size; $i++) {
fwrite($fp, $this->readbytes(512), 512);
}
if(($header['size'] % 512) != 0) fwrite($fp, $this->readbytes(512), $header['size'] % 512);
fclose($fp);
touch($output, $header['mtime']);
chmod($output, $header['perm']);
} else {
$this->skipbytes(ceil($header['size'] / 512) * 512); // the size is usually 0 for directories
}
} else {
$this->skipbytes(ceil($header['size'] / 512) * 512);
}
}
$this->close();
return $extracted;
}
/**
* Create a new TAR file
*
* If $file is empty, the tar file will be created in memory
*
* @param string $file
* @param int $comptype
* @param int $complevel
* @throws VerboseTarIOException
* @throws VerboseTarIllegalCompressionException
*/
public function create($file = '', $comptype = self::COMPRESS_AUTO, $complevel = 9) {
// determine compression
if($comptype == self::COMPRESS_AUTO) $comptype = $this->filetype($file);
$this->compressioncheck($comptype);
$this->comptype = $comptype;
$this->file = $file;
$this->memory = '';
$this->fh = 0;
if($this->file) {
if($this->comptype === self::COMPRESS_GZIP) {
$this->fh = @gzopen($this->file, 'wb'.$complevel);
} elseif($this->comptype === self::COMPRESS_BZIP) {
$this->fh = @bzopen($this->file, 'w');
} else {
$this->fh = @fopen($this->file, 'wb');
}
if(!$this->fh) throw new VerboseTarIOException('Could not open file for writing: '.$this->file);
}
$this->writeaccess = true;
$this->closed = false;
}
/**
* Add a file to the current TAR archive using an existing file in the filesystem
*
* @todo handle directory adding
* @param string $file the original file
* @param string $name the name to use for the file in the archive
* @throws VerboseTarIOException
*/
public function addFile($file, $name = '') {
if($this->closed) throw new VerboseTarIOException('Archive has been closed, files can no longer be added');
if(!$name) $name = $file;
$name = $this->cleanPath($name);
$fp = fopen($file, 'rb');
if(!$fp) throw new VerboseTarIOException('Could not open file for reading: '.$file);
// create file header and copy all stat info from the original file
clearstatcache(false, $file);
$stat = stat($file);
$this->writeFileHeader(
$name,
$stat[4],
$stat[5],
fileperms($file),
filesize($file),
filemtime($file)
);
while(!feof($fp)) {
$data = fread($fp, 512);
if($data === false) break;
if($data === '') break;
$packed = pack("a512", $data);
$this->writebytes($packed);
}
fclose($fp);
}
/**
* Add a file to the current TAR archive using the given $data as content
*
* @param string $name
* @param string $data
* @param int $uid
* @param int $gid
* @param int $perm
* @param int $mtime
* @throws VerboseTarIOException
*/
public function addData($name, $data, $uid = 0, $gid = 0, $perm = 0666, $mtime = 0) {
if($this->closed) throw new VerboseTarIOException('Archive has been closed, files can no longer be added');
$name = $this->cleanPath($name);
$len = strlen($data);
$this->writeFileHeader(
$name,
$uid,
$gid,
$perm,
$len,
($mtime) ? $mtime : time()
);
for($s = 0; $s < $len; $s += 512) {
$this->writebytes(pack("a512", substr($data, $s, 512)));
}
}
/**
* Add the closing footer to the archive if in write mode, close all file handles
*
* After a call to this function no more data can be added to the archive, for
* read access no reading is allowed anymore
*
* "Physically, an archive consists of a series of file entries terminated by an end-of-archive entry, which
* consists of two 512 blocks of zero bytes"
*
* @link http://www.gnu.org/software/tar/manual/html_chapter/tar_8.html#SEC134
*/
public function close() {
if($this->closed) return; // we did this already
// write footer
if($this->writeaccess) {
$this->writebytes(pack("a512", ""));
$this->writebytes(pack("a512", ""));
}
// close file handles
if($this->file) {
if($this->comptype === self::COMPRESS_GZIP) {
gzclose($this->fh);
} elseif($this->comptype === self::COMPRESS_BZIP) {
bzclose($this->fh);
} else {
fclose($this->fh);
}
$this->file = '';
$this->fh = 0;
}
$this->closed = true;
}
/**
* Returns the created in-memory archive data
*
* This implicitly calls close() on the Archive
*/
public function getArchive($comptype = self::COMPRESS_AUTO, $complevel = 9) {
$this->close();
if($comptype === self::COMPRESS_AUTO) $comptype = $this->comptype;
$this->compressioncheck($comptype);
if($comptype === self::COMPRESS_GZIP) return gzcompress($this->memory, $complevel);
if($comptype === self::COMPRESS_BZIP) return bzcompress($this->memory);
return $this->memory;
}
/**
* Save the created in-memory archive data
*
* Note: It more memory effective to specify the filename in the create() function and
* let the library work on the new file directly.
*
* @param $file
* @param int $comptype
* @param int $complevel
* @throws VerboseTarIOException
*/
public function save($file, $comptype = self::COMPRESS_AUTO, $complevel = 9) {
if($comptype === self::COMPRESS_AUTO) $comptype = $this->filetype($file);
if(!file_put_contents($file, $this->getArchive($comptype, $complevel))) {
throw new VerboseTarIOException('Could not write to file: '.$file);
}
}
/**
* Read from the open file pointer
*
* @param int $length bytes to read
* @return string
*/
protected function readbytes($length) {
if($this->comptype === self::COMPRESS_GZIP) {
return @gzread($this->fh, $length);
} elseif($this->comptype === self::COMPRESS_BZIP) {
return @bzread($this->fh, $length);
} else {
return @fread($this->fh, $length);
}
}
/**
* Write to the open filepointer or memory
*
* @param string $data
* @throws VerboseTarIOException
* @return int number of bytes written
*/
protected function writebytes($data) {
if(!$this->file) {
$this->memory .= $data;
$written = strlen($data);
} elseif($this->comptype === self::COMPRESS_GZIP) {
$written = @gzwrite($this->fh, $data);
} elseif($this->comptype === self::COMPRESS_BZIP) {
$written = @bzwrite($this->fh, $data);
} else {
$written = @fwrite($this->fh, $data);
}
if($written === false) throw new VerboseTarIOException('Failed to write to archive stream');
return $written;
}
/**
* Skip forward in the open file pointer
*
* This is basically a wrapper around seek() (and a workaround for bzip2)
*
* @param int $bytes seek to this position
*/
function skipbytes($bytes) {
if($this->comptype === self::COMPRESS_GZIP) {
@gzseek($this->fh, $bytes, SEEK_CUR);
} elseif($this->comptype === self::COMPRESS_BZIP) {
// there is no seek in bzip2, we simply read on
@bzread($this->fh, $bytes);
} else {
@fseek($this->fh, $bytes, SEEK_CUR);
}
}
/**
* Write a file header
*
* @param string $name
* @param int $uid
* @param int $gid
* @param int $perm
* @param int $size
* @param int $mtime
* @param string $typeflag Set to '5' for directories
*/
protected function writeFileHeader($name, $uid, $gid, $perm, $size, $mtime, $typeflag = '') {
// handle filename length restrictions
$prefix = '';
$namelen = strlen($name);
if($namelen > 100) {
$file = basename($name);
$dir = dirname($name);
if(strlen($file) > 100 || strlen($dir) > 155) {
// we're still too large, let's use GNU longlink
$this->writeFileHeader('././@LongLink', 0, 0, 0, $namelen, 0, 'L');
for($s = 0; $s < $namelen; $s += 512) {
$this->writebytes(pack("a512", substr($name, $s, 512)));
}
$name = substr($name, 0, 100); // cut off name
} else {
// we're fine when splitting, use POSIX ustar
$prefix = $dir;
$name = $file;
}
}
// values are needed in octal
$uid = sprintf("%6s ", decoct($uid));
$gid = sprintf("%6s ", decoct($gid));
$perm = sprintf("%6s ", decoct($perm));
$size = sprintf("%11s ", decoct($size));
$mtime = sprintf("%11s", decoct($mtime));
$data_first = pack("a100a8a8a8a12A12", $name, $perm, $uid, $gid, $size, $mtime);
$data_last = pack("a1a100a6a2a32a32a8a8a155a12", $typeflag, '', 'ustar', '', '', '', '', '', $prefix, "");
for($i = 0, $chks = 0; $i < 148; $i++)
$chks += ord($data_first[$i]);
for($i = 156, $chks += 256, $j = 0; $i < 512; $i++, $j++)
$chks += ord($data_last[$j]);
$this->writebytes($data_first);
$chks = pack("a8", sprintf("%6s ", decoct($chks)));
$this->writebytes($chks.$data_last);
}
/**
* Decode the given tar file header
*
* @param string $block a 512 byte block containign the header data
* @return array|bool
*/
protected function parseHeader($block) {
if(!$block || strlen($block) != 512) return false;
for($i = 0, $chks = 0; $i < 148; $i++)
$chks += ord($block[$i]);
for($i = 156, $chks += 256; $i < 512; $i++)
$chks += ord($block[$i]);
$header = @unpack("a100filename/a8perm/a8uid/a8gid/a12size/a12mtime/a8checksum/a1typeflag/a100link/a6magic/a2version/a32uname/a32gname/a8devmajor/a8devminor/a155prefix", $block);
if(!$header) return false;
$return['checksum'] = OctDec(trim($header['checksum']));
if($return['checksum'] != $chks) return false;
$return['filename'] = trim($header['filename']);
$return['perm'] = OctDec(trim($header['perm']));
$return['uid'] = OctDec(trim($header['uid']));
$return['gid'] = OctDec(trim($header['gid']));
$return['size'] = OctDec(trim($header['size']));
$return['mtime'] = OctDec(trim($header['mtime']));
$return['typeflag'] = $header['typeflag'];
$return['link'] = trim($header['link']);
$return['uname'] = trim($header['uname']);
$return['gname'] = trim($header['gname']);
// Handle ustar Posix compliant path prefixes
if(trim($header['prefix'])) $return['filename'] = trim($header['prefix']).'/'.$return['filename'];
// Handle Long-Link entries from GNU Tar
if($return['typeflag'] == 'L') {
// following data block(s) is the filename
$filename = trim($this->readbytes(ceil($header['size'] / 512) * 512));
// next block is the real header
$block = $this->readbytes(512);
$return = $this->parseHeader($block);
// overwrite the filename
$return['filename'] = $filename;
}
return $return;
}
/**
* Cleans up a path and removes relative parts, also strips leading slashes
*
* @param string $p_dir
* @return string
*/
public function cleanPath($path) {
$path=explode('/', $path);
$newpath=array();
foreach($path as $p) {
if ($p === '' || $p === '.') continue;
if ($p==='..') {
array_pop($newpath);
continue;
}
array_push($newpath, $p);
}
return trim(implode('/', $newpath), '/');
}
/**
* Checks if the given compression type is available and throws an exception if not
*
* @param $comptype
* @throws VerboseTarIllegalCompressionException
*/
protected function compressioncheck($comptype) {
if($comptype === self::COMPRESS_GZIP && !function_exists('gzopen')) {
throw new VerboseTarIllegalCompressionException('No gzip support available');
}
if($comptype === self::COMPRESS_BZIP && !function_exists('bzopen')) {
throw new VerboseTarIllegalCompressionException('No bzip2 support available');
}
}
/**
* Guesses the wanted compression from the given filename extension
*
* You don't need to call this yourself. It's used when you pass self::COMPRESS_AUTO somewhere
*
* @param string $file
* @return int
*/
public function filetype($file) {
$file = strtolower($file);
if(substr($file, -3) == '.gz' || substr($file, -4) == '.tgz') {
$comptype = self::COMPRESS_GZIP;
} elseif(substr($file, -4) == '.bz2' || substr($file, -4) == '.tbz') {
$comptype = self::COMPRESS_BZIP;
} else {
$comptype = self::COMPRESS_NONE;
}
return $comptype;
}
}
class VerboseTarIOException extends Exception {
}
class VerboseTarIllegalCompressionException extends Exception {
}