public bool Download(Peer peer, RingInfo ringInfo, ResourceHeader resourceHeader,
UICallBack UIHndlr)
{
Download download = new Download(peer, ringInfo, resourceHeader, UIHndlr);
int downloadIndex = Add(download);
if (downloadIndex < 0)
{
Queue(download);
return false;
}
Download_Internal(download);
return true;
}
public void Download_Internal(Download download)
{
//REVISIT:first try downloading from single source and then try parallelizing
byte[] message = new byte[Constants.WRITEBUFFSIZE];
byte[] buffer = new Byte[Constants.READBUFFSIZE];
MemoryStream stream;
BinaryReader reader = null;
BinaryWriter writer = null;
//REVISIT: when implementing parallel downloads, need to change these dynamically
int offset = 0;
int bytesToDownload = (int)download.header.size;
try
{
BinaryFormatter serializer = new BinaryFormatter();
stream = new MemoryStream(message);
NetLib.insertEntropyHeader(serializer, stream);
serializer.Serialize(stream, Constants.MessageTypes.MSG_DOWNLOADREQUEST);
serializer.Serialize(stream, download.ringInfo.token);
serializer.Serialize(stream, download.ringInfo.ring.ringID);
serializer.Serialize(stream, User.getInstance().node.syncCommunicationPoint);
serializer.Serialize(stream, download.header);
serializer.Serialize(stream, offset);
serializer.Serialize(stream, bytesToDownload);
//Send out the request for download
NetworkStream networkStream = NetLib.OpenCommunicationChannel(download.peer.node.syncCommunicationPoint);
reader = new BinaryReader(networkStream);
writer = new BinaryWriter(networkStream);
writer.Write(message);
writer.Flush();
stream.Close();
reader.Read(buffer, 0, buffer.Length);
BinaryFormatter deserializer = new BinaryFormatter();
stream = new MemoryStream(buffer);
NetLib.bypassEntropyHeader(deserializer, stream);
Constants.MessageTypes replyMsg = (Constants.MessageTypes)deserializer.Deserialize(stream);
switch(replyMsg)
{
case Constants.MessageTypes.MSG_DOWNLOADREPLY:
long leftToDownload = download.header.size;
byte[] firstResourceChunk = (byte[])deserializer.Deserialize(stream);
//Insert the initial chunk into the download buffer.
//REVISIT: figure a way to just deserialize into download.buffer (avoids a copy)
firstResourceChunk.CopyTo(download.buffer, 0);
long bytesReadOnThisRead = firstResourceChunk.Length;
download.bytesRead += bytesReadOnThisRead;
leftToDownload -= bytesReadOnThisRead;
download.UIHandler.Invoke(bytesReadOnThisRead);
while (leftToDownload > 0 && bytesReadOnThisRead > 0)
{
bytesReadOnThisRead = reader.Read(download.buffer, (int)download.bytesRead,
download.buffer.Length-(int)download.bytesRead);
download.bytesRead += bytesReadOnThisRead;
leftToDownload -= bytesReadOnThisRead;
download.UIHandler.Invoke(bytesReadOnThisRead);
System.Threading.Thread.Sleep(10);
}
Debug.Assert(download.bytesRead == download.header.size, "Did not receive the entire file");
break;
default:
Remove(download);
Queue(download);
break;
}
}
catch (Exception e)
{
int x = 2; //REVISIT: probably need to send info to logger.
}
finally
{
if (reader != null && writer != null)
{
reader.Close();
writer.Close();
}
}
}
private void Queue(Download download)
{
pendingDownloads.Enqueue(download);
}
private void Remove(Download download)
{
for (int index = 0; index < downloads.Length; index++)
{
if (downloads[index] == download)
downloads[index] = null;
}
}
private int Add(Download download)
{
for (int index = 0; index < downloads.Length; index++)
{
if (downloads[index] == null)
{
downloads[index] = download;
return index;
}
}
return -1;
}
