From 991bafa2e5f48a232e0c62ce331bb893f119f58c Mon Sep 17 00:00:00 2001
From: "Janus B. Kristensen" <jbk@visualgroup.dk>
Date: Wed, 23 May 2007 15:45:34 +0000
Subject: [PATCH] Added IllegalArgumentException and the class representing
 .torrent-files

svn path=/trunk/boinc/; revision=12726
---
 html/bt/inc/torrent.php | 89 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 89 insertions(+)
 create mode 100755 html/bt/inc/torrent.php

diff --git a/html/bt/inc/torrent.php b/html/bt/inc/torrent.php
new file mode 100755
index 0000000000..8e058a7dce
--- /dev/null
+++ b/html/bt/inc/torrent.php
@@ -0,0 +1,89 @@
+<?php
+
+/**
+ * A .torrent is a metafile containing info about a P2P file
+ * This class encapsulates all related .torrent information
+ * for a single file.
+ * We don't seem to need multifile support since the clients can
+ * simply download a .torrent for each file they want to fetch.
+ */ 
+
+$cvs_version_tracker[]="\$Id$";  //Generated automatically - do not edit
+ 
+class Torrent {
+    private $trackerURL; // String
+    private $name;  // String
+    private $pieceLength = 524288; // (512KB)
+    private $filename; // String
+    private $webseeds; // URL String Array
+    
+    private $concattedSHA1; // Imploded string of SHA1 hashes
+    private $generatedPieceLength;
+    private $infoHash;
+    
+    /**
+     * Filename is the full path to the file to be encapsulated.
+     */
+    function __construct($filename, $trackerURL, $webseeds=array()){
+	if (!file_exists($filename)) throw new IllegalArgumentException("No such file found");
+
+	$this->filename = $filename;
+	$this->trackerURL = $trackerURL;
+	$this->webseeds = $webseeds;
+	$this->name = basename($filename);
+    }
+    
+    /** 
+     * Scans the entire file generating SHA1 hashes for each piece
+     */
+    public function ensureSHA1Loaded(){
+	if (!$this->concattedSHA1 || ($this->pieceLength!=$this->generatedPieceLength)){
+	    $fh = fopen($this->filename, "rb");
+	    if (!$fh) throw new Exception("No filehandle");
+	    $fsize = filesize($this->filename);
+	    $this->concattedSHA1 = "";
+	    for ($i = 0; $i<ceil($fsize/$this->pieceLength); $i++){
+		fseek($fh, $i*$this->pieceLength);
+		$this->concattedSHA1 .= sha1(fread($fh,$this->pieceLength), true);
+	    }
+	    $this->generatedPieceLength = $this->pieceLength;
+	    fclose($fh);
+	    if (!$this->concattedSHA1) throw new Exception("No SHA gotten");
+	}
+	
+    }
+    
+    /**
+     * Fetches all relevant information from the file and generates a 
+     * .torrent
+     */
+    public function toEncoded(){
+	$infoArray["name"] = $this->name;
+	$infoArray["piece length"] = $this->pieceLength;
+	$infoArray["length"] = filesize($this->filename);
+	$this->ensureSHA1Loaded();
+	$infoArray["pieces"] = $this->concattedSHA1;
+	$infoDictionary = new BElement(BDictionary::toEncoded($infoArray));
+	$this->infoHash = sha1($infoDictionary->toEncoded(), true);
+	$metainfoArray = array("announce"=>$this->trackerURL, "info"=>$infoDictionary);
+	$metainfoArray["url-list"] = new BElement(BList::toEncoded($this->webseeds));
+	$metainfoDictionary = BDictionary::toEncoded($metainfoArray);
+	
+	return $metainfoDictionary;
+    }
+    
+    /**
+     * Registers this torrent in the database
+     */
+    public function register(){
+	$this->toEncoded();
+	// Check if exists:
+	$queryHandle = mysql_query("SELECT id from bittorrent_files where filename=\"".process_user_text($this->filename)."\"");
+	if ($queryHandle && $data = mysql_fetch_object($queryHandle)){
+	    $extra = "id=".$data->id.", ";
+	} else {
+	    $extra = "";
+	}
+	mysql_query("REPLACE into bittorrent_files set ".$extra."filename=\"".process_user_text($this->filename)."\", info_hash=\"".process_user_text($this->infoHash)."\", timestamp=".time());	    
+    }
+}
\ No newline at end of file