Torrent management: torrent parser script (extract torrent dir.php)
The torrent parser script is used to extract the top-level directory (or filename if the torrent is one file) for the torrent. It is assumed that the torrent does NOT contain multiple top-level directories or file (I've never seen this in a proper torrent, myself).
<?php
require_once 'Torrent.php';
if ( $argv[1] == "" )
{
echo "Give me a torrent.";
exit;
}
$torrent = new Torrent( $argv[1] );
// var_dump( $torrent->content() );
// First, pull out the "keys", they are the file names. The values are the hashes, it seems.
$torrent_files = array_keys( $torrent->content() );
// Now get the first key.
$first_file = $torrent_files[0];
// Now make sure everything after the first backslash is trimmed.
if ( strpos( $first_file, "/" ) )
{
$first_file = substr( $first_file, 0, strpos( $first_file, "/" ) );
}
// Write it out!
echo $first_file;
?>
All the heavy lifting is done by a php torrent class library, called TorrentRW, that I found here. Thanks Adrien Gibrat!! Here's an archive of Torrent.php version 0.1 (which works for me):
<?php
/**
* Torrent
*
* PHP version 5 only
*
* LICENSE: This source file is subject to version 3 of the GNU GPL
* that is available through the world-wide-web at the following URI:
* http://www.gnu.org/licenses/gpl.html. If you did not receive a copy of
* the GNU GPL License and are unable to obtain it through the web, please
* send a note to adrien.gibrat@gmail.com so I can mail you a copy.
*
* 1) Features:
* - Decode torrent file or data
* - Build torrent from source folder/file(s)
* - Silent Exception error system
*
* 2) Usage example
* <code>
require_once 'Torrent.php';
// get torrent infos
$torrent = new Torrent( './test.torrent' );
echo '<br>private: ', $torrent->is_private() ? 'yes' : 'no',
'<br>annonce: ', $torrent->announce(),
'<br>name: ', $torrent->name(),
'<br>comment: ', $torrent->comment(),
'<br>piece_length: ', $torrent->piece_length(),
'<br>size: ', $torrent->size( 2 ),
'<br>hash info: ', $torrent->hash_info(),
'<br>stats: ';
var_dump( $torrent->scrape() );
echo '<br>content: ';
var_dump( $torrent->content() );
echo '<br>source: ',
$torrent;
// create torrent
$torrent = new Torrent( array( 'test.mp3', 'test.jpg' ), 'http://torrent.tracker/annonce' );
$torrent->send();
// print errors
if ( $errors = $torrent->errors() )
var_dump( $errors );
* </code>
*
* @author Adrien Gibrat <adrien.gibrat@gmail.com>
* @copyleft 2008 - Just use it!
* @license http://www.gnu.org/licenses/gpl.html GNU General Public License version 3
* @version Release: 0.1
*/
class Torrent {
static public $errors = array();
/** Read and decode torrent file/data OR build a torrent from source folder/file(s)
* Supported signatures:
* - Torrent( string $torrent );
* - Torrent( string $torrent, string $announce );
* - Torrent( string $torrent, array $meta );
* - Torrent( string $file_or_folder );
* - Torrent( string $file_or_folder, string $announce_url, [int $piece_length] );
* - Torrent( string $file_or_folder, array $meta, [int $piece_length] );
* - Torrent( array $files_list );
* - Torrent( array $files_list, string $announce_url, [int $piece_length] );
* - Torrent( array $files_list, array $meta, [int $piece_length] );
* @param string|array torrent to read or source folder/file(s)
* @param string|array announce url or meta informations (optional)
* @param int piece length (optional)
*/
public function __construct ( $data, $meta = array(), $piece_length = 256 )
{
if ( $piece_length < 32 || $piece_length > 4096 ) {
throw new Exception( __( 'Invalid piece lenth, must be between 32 and 4096' ) );
}
if ( is_string( $meta ) ) {
$meta = array( 'announce' => $meta );
}
if ( $this->build( $data, $piece_length * 1024 ) ) {
$this->touch();
} else {
$meta = array_merge( $meta, $this->decode( $data ) );
}
foreach( $meta as $key => $value ) {
$this->{$key} = $value;
}
}
/** Convert the current Torrent instance in torrent format
* @return string encoded torrent data
*/
public function __toString()
{
return $this->encode( $this );
}
/** Return Errors
* @return array|boolean error list or null if none
*/
public function errors()
{
return empty( self::$errors ) ?
false :
self::$errors;
}
/**** Encode BitTorrent ****/
/** Encode torrent data
* @param mixed data to encode
* @return string torrent encoded data
*/
static protected function encode ( $mixed )
{
switch ( gettype( $mixed ) ) {
case 'integer':
case 'double':
return self::encode_integer( $mixed );
case 'object':
$mixed = (array) $mixed; //Bugfix by W-Shadow. Objects can't be ksort'ed anyway (see encode_array()).
case 'array':
return self::encode_array( $mixed );
default:
return self::encode_string( (string) $mixed );
}
}
/** Encode torrent string
* @param string string to encode
* @return string encoded string
*/
static private function encode_string ( $string )
{
return strlen( $string ) . ':' . $string;
}
/** Encode torrent integer
* @param integer integer to encode
* @return string encoded integer
*/
static private function encode_integer ( $integer )
{
return 'i' . $integer . 'e';
}
/** Encode torrent dictionary or list
* @param array array to encode
* @return string encoded dictionary or list
*/
static private function encode_array ( $array )
{
if ( self::is_list( (array) $array ) ) {
$return = 'l';
foreach ( $array as $value ) {
$return .= self::encode( $value );
}
} else {
ksort( $array, SORT_STRING );
$return = 'd';
foreach ( $array as $key => $value ) {
$return .= self::encode( strval( $key ) ) . self::encode( $value );
}
}
return $return . 'e';
}
/** Helper to test if an array is a list
* @param array array to test
* @return boolean is the array a list
*/
static protected function is_list ( $array )
{
foreach ( array_keys( $array ) as $key ) {
if ( ! is_int( $key ) ) {
return false;
}
}
return true;
}
/**** Decode BitTorrent ****/
/** Decode torrent data or file
* @param string data or file path to decode
* @return array decoded torrent data
*/
static protected function decode ( $string )
{
$data = is_file( $string ) ?
file_get_contents( $string ) :
$string;
return self::decode_data( $data );
}
/** Decode torrent data
* @param string data to decode
* @return array decoded torrent data
*/
static protected function decode_data ( & $data )
{
switch( self::char( $data ) ) {
case 'i':
$data = substr( $data, 1 );
return self::decode_integer( $data );
case 'l':
$data = substr( $data, 1 );
return self::decode_list( $data );
case 'd':
$data = substr( $data, 1 );
return self::decode_dictionary( $data );
default:
return self::decode_string( $data );
}
}
/** Decode torrent dictionary
* @param string data to decode
* @return array decoded dictionary
*/
static private function decode_dictionary ( & $data )
{
$dictionary = array();
$previous = null;
while ( ( $char = self::char( $data ) ) != 'e' ) {
if ( $char === false ) {
throw new Exception( __( 'Unterminated dictionary' ) );
}
if ( ! ctype_digit( $char ) ) {
throw new Exception( __( 'Invalid dictionary key' ) );
}
$key = self::decode_string( $data );
if ( isset( $dictionary[$key] ) ) {
throw new Exception( __( 'Duplicate dictionary key' ) );
}
if ( $key < $previous ) {
throw new Exception( __( 'Missorted dictionary key' ) );
}
$dictionary[$key] = self::decode_data( $data );
$previous = $key;
}
$data = substr( $data, 1 );
return $dictionary;
}
/** Decode torrent list
* @param string data to decode
* @return array decoded list
*/
static private function decode_list ( & $data )
{
$list = array();
while ( ( $char = self::char( $data ) ) != 'e' ) {
if ( $char === false ) {
throw new Exception( 'Unterminated list' );
}
$list[] = self::decode_data( $data );
}
$data = substr( $data, 1 );
return $list;
}
/** Decode torrent string
* @param string data to decode
* @return string decoded string
*/
static private function decode_string ( & $data )
{
if ( self::char( $data ) === '0' && substr( $data, 1, 1 ) != ':' ) {
self::$errors[] = new Exception( 'Invalid string length, leading zero' );
}
if ( ! $colon = @strpos( $data, ':' ) ) {
throw new Exception( 'Invalid string length, colon not found' );
}
$length = intval( substr( $data, 0, $colon ) );
if ( $length + $colon + 1 > strlen( $data ) ) {
throw new Exception( 'Invalid string, input too short for string length' );
}
$string = substr( $data, $colon + 1, $length );
$data = substr( $data, $colon + $length + 1 );
return $string;
}
/** Decode torrent integer
* @param string data to decode
* @return integer decoded integer
*/
static private function decode_integer ( & $data )
{
$start = 0;
$end = strpos( $data, 'e');
if ( $end === 0 )
self::$errors[] = new Exception( 'Empty integer' );
if ( self::char( $data ) == '-' )
$start++;
if ( substr( $data, $start, 1 ) == '0' && ( $start != 0 || $end > $start + 1 ) )
self::$errors[] = new Exception( 'Leading zero in integer' );
if ( ! ctype_digit( substr( $data, $start, $end ) ) )
self::$errors[] = new Exception( 'Non-digit characters in integer' );
$integer = substr( $data, 0, $end );
$data = substr( $data, $end + 1 );
return $integer + 0;
}
/** Helper to return the first char of encoded data
* @param string encoded data
* @return string|boolean first char of encoded data or false if empty data
*/
static private function char ( $data )
{
return empty( $data ) ?
false :
substr( $data, 0, 1 );
}
/**** Make BitTorrent ****/
/** Getter and setter of torrent annouce url
* @param null|string annouce url (optional, if omitted it's a getter)
* @return string|null annouce url or null if not set
*/
public function announce ( $announce = null )
{
return is_null( $announce ) ?
isset( $this->announce ) ? $this->announce : null :
$this->touch( $this->announce = (string) $announce );
}
/** Getter and setter of torrent annouce list
* @param null|array annouce list (optional, if omitted it's a getter)
* @return array|null annouce list or null if not set
*/
public function announce_list ( $announce_list = null )
{
return is_null( $announce_list ) ?
isset( $this->{'announce-list'} ) ? $this->{'announce-list'} : null :
$this->touch( $this->{'announce-list'} = (array) $announce_list );
}
/** Getter and setter of torrent comment
* @param null|string comment (optional, if omitted it's a getter)
* @return string|null comment or null if not set
*/
public function comment ( $comment = null )
{
return is_null( $comment ) ?
isset( $this->comment ) ? $this->comment : null :
$this->touch( $this->comment = (string) $comment );
}
/** Getter and setter of torrent name
* @param null|string name (optional, if omitted it's a getter)
* @return string|null name or null if not set
*/
public function name ( $name = null )
{
return is_null( $name ) ?
isset( $this->info['name'] ) ? $this->info['name'] : null :
$this->touch( $this->info['name'] = (string) $name );
}
/** Getter and setter of private flag
* @param null|boolean is private or not (optional, if omitted it's a getter)
* @return boolean private flag
*/
public function is_private ( $private = null )
{
return is_null( $private ) ?
! empty( $this->info['private'] ) :
$this->touch( $this->info['private'] = $private ? 1 : 0 );
}
/** Getter and setter of webseed(s) url list ( GetRight implementation )
* @param null|string|array webseed or webseeds mirror list (optional, if omitted it's a getter)
* @return string|array|null webseed(s) or null if not set
*/
public function url_list ( $urls = null )
{
return is_null( $urls ) ?
isset( $this->{'url-list'} ) ? $this->{'url-list'} : null :
$this->touch( $this->{'url-list'} = $urls );
}
/** Getter and setter of httpseed(s) url list ( Bittornado implementation )
* @param null|string|array httpseed or httpseeds mirror list (optional, if omitted it's a getter)
* @return array|null httpseed(s) or null if not set
*/
public function httpseeds ( $urls = null )
{
return is_null( $urls ) ?
isset( $this->httpseeds ) ? $this->httpseeds : null :
$this->touch( $this->httpseeds = (array) $urls );
}
/** Save torrent file to disk
* @param null|string name of the file (optional)
* @return boolean file has been saved or not
*/
public function save ( $filename = null )
{
return file_put_contents( is_null( $filename ) ? $this->info['name'] . '.torrent' : $filename, $this );
}
/** Send torrent file to client
* @param null|string name of the file (optional)
* @return void script exit
*/
public function send ( $filename = null )
{
$data = (string) $this;
header( 'Content-type: application/x-bittorrent' );
header( 'Content-Length: ' . strlen( $data ) );
header( 'Last-Modified: ' . gmdate( 'D, d M Y H:i:s', $this->{'creation date'} ) . ' GMT');
header( 'Content-Disposition: attachment; filename="' . ( is_null( $filename ) ? $this->info['name'] . '.torrent' : $filename ) . '"' );
exit( $data );
}
/** Build torrent info
* @param string|array source folder/file(s) path
* @param integer piece length
* @return array|boolean torrent info or false if data isn't folder/file(s)
*/
protected function build ( $data, $piece_length )
{
if ( is_null( $data ) )
return false;
elseif ( is_array( $data ) && self::is_list( $data ) )
return $this->info = $this->files( $data, $piece_length );
elseif ( is_dir( $data ) )
return $this->info = $this->folder( $data, $piece_length );
elseif ( is_file( $data ) && pathinfo( $data, PATHINFO_EXTENSION ) != 'torrent' )
return $this->info = $this->file( $data, $piece_length );
else
return false;
}
/** Build torrent info from single file
* @param string file path
* @param integer piece length
* @return array torrent info
*/
private function file ( $file, $piece_length )
{
if ( ! $handle = self::fopen( $file, $size = self::filesize( $file ) ) ) {
return ! self::$errors[] = new Exception( 'Failed to open file: "' . $file . '"' );
}
$pieces = '';
while ( ! feof( $handle ) )
$pieces .= self::pack( fread( $handle, $piece_length ) );
fclose( $handle );
return array(
'length' => $size,
'name' => basename( $file ),
'piece length' => $piece_length,
'pieces' => $pieces
);
}
/** Build torrent info from files
* @param array file list
* @param integer piece length
* @return array torrent info
*/
private function files ( $files, $piece_length )
{
$files = array_map( 'realpath', $files );
sort( $files );
usort( $files, create_function( '$a,$b', 'return strrpos($a,DIRECTORY_SEPARATOR)-strrpos($b,DIRECTORY_SEPARATOR);' ) );
$path = explode( DIRECTORY_SEPARATOR, dirname( realpath( current( $files ) ) ) );
$length = $piece_length;
$piece = $pieces = '';
foreach ( $files as $i => $file ) {
if ( $path != array_intersect_assoc( $file_path = explode( DIRECTORY_SEPARATOR, $file ), $path ) ) {
continue self::$errors[] = new Exception( 'Files must be in the same folder: "' . $file . '" discarded' );
}
if ( ! $handle = self::fopen( $file, $filesize = self::filesize( $file ) ) ) {
continue self::$errors[] = new Exception( 'Failed to open file: "' . $file . '" discarded' );
}
while ( ! feof( $handle ) ) {
if ( ( $length = strlen( $piece .= fread( $handle, $length ) ) ) == $piece_length ) {
$pieces .= self::pack( $piece );
} else {
$length = $piece_length - $length;
}
}
fclose( $handle );
$info_files[$i] = array(
'length' => $filesize,
'path' => array_diff( $file_path, $path )
);
}
switch ( count( $info_files ) ) {
case 0:
return false;
case 1:
return $this->file( $files[key( $info_files )], $piece_length );
default:
return array(
'files' => $info_files,
'name' => end( $path ),
'piece length' => $piece_length,
'pieces' => $pieces . ( $piece ? self::pack( $piece ) : '' )
);
}
}
/** Build torrent info from folder content
* @param string folder path
* @param integer piece length
* @return array torrent info
*/
private function folder ( $dir, $piece_length ) {
return $this->files( self::scandir( $dir ), $piece_length );
}
/** Set torrent creator and creation date
* @return void
*/
protected function touch () {
$this->{'created by'} = 'Torrent PHP Class - Adrien Gibrat';
$this->{'creation date'} = time();
}
/** Helper to return filesize (even bigger than 2Gb, linux only)
* @param string file path
* @return double|boolean filesize or false if error
*/
static public function filesize ( $file ) {
return ( $size = @filesize( $file ) ) !== false ?
(double) sprintf( '%u', $size ) :
false;
}
/** Helper to open file to read (even bigger than 2Gb, linux only)
* @param string file path
* @param integer|double file size (optional)
* @return ressource|boolean file handle or false if error
*/
static public function fopen ( $file, $size = null ) {
if ( ( is_null( $size ) ? self::filesize( $file ) : $size ) <= 2 * pow( 1024, 3 ) )
return fopen( $file, 'r' );
elseif ( PHP_OS != 'Linux' )
return ! self::$errors[] = new Exception( 'File size is greater than 2GB. This is only supported under Linux' );
elseif ( ! is_readable( $file ) )
return false;
else
return popen( 'cat ' . escapeshellarg( realpath( $file ) ), 'r' );
}
/** Helper scan directories files and sub directories recursivly
* @param string directory path
* @return array directory content list
*/
static public function scandir ( $dir ) {
$paths = array();
foreach ( scandir( $dir ) as $item )
if ( $item != '.' && $item != '..' )
if ( is_dir( $path = realpath( $dir . DIRECTORY_SEPARATOR . $item ) ) )
$paths = array_merge( self::scandir( $path ), $paths );
else
$paths[] = $path;
return $paths;
}
/** Helper to pack data hash
* @param string data
* @return string packed data hash
*/
static protected function pack ( & $data ) {
return pack('H*', sha1( $data ) ) . ( $data = '' );
}
/**** Analyze BitTorrent ****/
/** Get piece length
* @return integer piece length or null if not set
*/
public function piece_length () {
return isset( $this->info['piece length'] ) ?
$this->info['piece length'] :
null;
}
/** Compute hash info
* @return string hash info or null if info not set
*/
public function hash_info () {
return isset( $this->info ) ?
sha1( self::encode( $this->info ) ) :
null;
}
/** List torrent content
* @param integer|null size precision (optional, if omitted returns sizes in bytes)
* @return array file(s) and size(s) list, files as keys and sizes as values
*/
public function content ( $precision = null ) {
$files = array();
if ( is_array( $this->info['files'] ) )
foreach ( $this->info['files'] as $file )
$files[self::path( $file['path'], $this->info['name'] )] = $precision ?
self::format( $file['length'], $precision ) :
$file['length'];
elseif ( isset( $this->info['name'] ) )
$files[$this->info['name']] = $precision ?
self::format( $this->info['length'], $precision ) :
$this->info['length'];
return $files;
}
/** List torrent content pieces and offset(s)
* @return array file(s) and pieces/offset(s) list, file(s) as keys and pieces/offset(s) as values
*/
public function offset () {
$files = array();
$size = 0;
if ( is_array( $this->info['files'] ) )
foreach ( $this->info['files'] as $file )
$files[self::path( $file['path'], $this->info['name'] )] = array(
'startpiece' => floor( $size / $this->info['piece length'] ),
'offset' => fmod( $size, $this->info['piece length'] ),
'size' => $size += $file['length'],
'endpiece' => floor( $size / $this->info['piece length'] )
);
elseif ( isset( $this->info['name'] ) )
$files[$this->info['name']] = array(
'startpiece' => 0,
'offset' => 0,
'size' => $this->info['length'],
'endpiece' => floor( $this->info['length'] / $this->info['piece length'] )
);
return $files;
}
/** Sum torrent content size
* @param integer|null size precision (optional, if omitted returns size in bytes)
* @return integer|string file(s) size
*/
public function size ( $precision = null ) {
$size = 0;
if ( is_array( $this->info['files'] ) )
foreach ( $this->info['files'] as $file )
$size += $file['length'];
elseif ( isset( $this->info['name'] ) )
$size = $this->info['length'];
return is_null( $precision ) ?
$size :
self::format( $size, $precision );
}
/** Request torrent statistics from scrape page
* @param string announce or scrape page url (optional, to request an alternative tracker BUT mandatory for static call)
* @param string torrent hash info (optional: ONLY for static call)
* @return array tracker torrent statistics
*/
/* static */ public function scrape ( $announce = null, $hash_info = null ) {
if ( ! ini_get( 'allow_url_fopen' ) )
return ! self::$errors[] = new Exception( '"allow_url_fopen" must be enabled' );
$packed_hash = pack('H*', $hash_info ? $hash_info : sha1( self::encode( $this->info ) ) );
$scrape_data = file_get_contents( str_ireplace( '/announce', '/scrape', $announce ? $announce : $this->announce ) . '?info_hash=' . urlencode( $packed_hash ) );
$stats = self::decode_data( $scrape_data );
return isset( $stats['files'][$packed_hash] ) ?
$stats['files'][$packed_hash] :
! self::$errors[] = new Exception( 'Invalid scrape data' );
}
/** Helper to build file path
* @param array file path
* @param string base folder
* @return string real file path
*/
static private function path ( $path, $folder ) {
array_unshift( $path, $folder );
return join( DIRECTORY_SEPARATOR, $path );
}
/** Helper to format size in bytes to human readable
* @param integer size in bytes
* @param integer precision after coma
* @return string formated size in appropriate unit
*/
static public function format ( $size, $precision = 2 ) {
$units = array ('octets', 'Ko', 'Mo', 'Go', 'To');
while( ( $next = next( $units ) ) && $size > 1024 )
$size /= 1024;
return round( $size, $precision ) . ' ' . ( $next ? prev( $units ) : end( $units ) );
}
}
?>