public static int DecideNextPiece(DownloadStrategyManager manager, Peer peer)
{
int pieceId = -1;
int lowestNumPeers = -1;
// find the rarest piece in the swarm which is owned by the peer
for (int i = 0; i < manager.PieceCounter.PieceCount; ++i)
{
// make sure the peer owns the piece, the piece hasn't already been downloaded,
// has at least one peer and isn't in the process of being downloaded
// by another peer
if (!manager.Torrent.DownloadFile.Bitfield.Get(i) && manager.PieceCounter[i] > 0 && !manager.IsPieceDownloading(i))
{
if (peer != null && !peer.BitField.Get(i))
{
continue;
}
// see if the piece has the lowest number of peers so far
if (manager.PieceCounter[i] < lowestNumPeers || lowestNumPeers == -1)
{
lowestNumPeers = manager.PieceCounter[i];
pieceId = i;
}
}
}
return(pieceId);
}
public static bool DoesPeerHavePieceWeDont(DownloadStrategyManager manager, Peer peer)
{
for (int i = 0; i < manager.Torrent.Metainfo.PieceCount; ++i)
{
if (peer.BitField.Get(i) && !manager.Torrent.DownloadFile.Bitfield.Get(i))
{
return(true);
}
}
return(false);
}
/// <summary>Contructs a torrent using the metainfo filename</summary>
/// <param name="metafilename">Filename of the metainfo file</param>
internal Torrent(Session session, string metafilename)
{
this.mSession = session;
this.infofile = new MetainfoFile(metafilename);
this.downloadFile = new DownloadFile(infofile);
this.peerManager = new PeerManager();
this.mDownloadStrategy = new DownloadStrategyManager(this);
this.uploadManager = new UploadManager(infofile, downloadFile);
this.tp = new TrackerProtocol(this, infofile, downloadFile);
// this.downloadManager.PieceFinished += new PieceFinishedCallback(downloadManager_PieceFinished);
this.uploadManager.PieceSectionFinished += new PieceSectionFinishedCallback(uploadManager_PieceSectionFinished);
this.tp.TrackerUpdate += new TrackerUpdateCallback(tp_TrackerUpdate);
}
public static void SetInterestedOnPeerIfNecessary(DownloadStrategyManager manager, Peer peer, int pieceId)
{
if (pieceId >= 0)
{
// new piece came in
if (!manager.Torrent.DownloadFile.Bitfield.Get(pieceId))
{
peer.AmIInterested = true;
}
}
else
{
// whole bitfield has changed
if (DoesPeerHavePieceWeDont(manager, peer))
{
peer.AmIInterested = true;
}
}
}
/// <summary>Contructs a torrent using the metainfo filename</summary>
/// <param name="metafilename">Filename of the metainfo file</param>
internal Torrent( Session session, string metafilename )
{
this.mSession = session;
this.infofile = new MetainfoFile(metafilename);
this.downloadFile = new DownloadFile(infofile);
this.peerManager = new PeerManager();
this.mDownloadStrategy = new DownloadStrategyManager( this );
this.uploadManager = new UploadManager(infofile, downloadFile);
this.tp = new TrackerProtocol(this, infofile, downloadFile);
// this.downloadManager.PieceFinished += new PieceFinishedCallback(downloadManager_PieceFinished);
this.uploadManager.PieceSectionFinished += new PieceSectionFinishedCallback(uploadManager_PieceSectionFinished);
this.tp.TrackerUpdate += new TrackerUpdateCallback(tp_TrackerUpdate);
}
public static void SetInterestedOnPeerIfNecessary(DownloadStrategyManager manager, Peer peer)
{
SetInterestedOnPeerIfNecessary(manager, peer, -1);
}
public static int CalculatePieceSectionLength(DownloadStrategyManager manager, int pieceId, int begin)
{
int pieceDataLeft = manager.Torrent.Metainfo.GetPieceLength(pieceId) - begin;
return(pieceDataLeft < Config.MaxRequestSize ? pieceDataLeft : Config.MaxRequestSize);
}
public DefaultDownloadStrategy(DownloadStrategyManager manager)
{
this.mManager = manager;
this.mEndGameStrategy = new EndGameDownloadStrategy(manager);
this.mManager.AddNewStrategy(this.mEndGameStrategy);
}
public EndGameDownloadStrategy(DownloadStrategyManager manager)
{
mManager = manager;
}
