/// <summary>
/// 如果向某个peer发送的获取“子片断”的请求丢失了，那么调用此函数
/// </summary>
/// <param name="index">子片断索引号</param>
/// <param name="request">请求子片断的信息</param>
public void RequestLost(int index, InactiveRequest request)
{
inactiveRequests[index].Add(request);
inactiveRequests[index].Sort();
numActive[index]--;
totalInactive++;
}
public InactiveRequest NewRequest(int index)
{
InactiveRequest result = requests[requests.Count - 1];
requests.RemoveAt(requests.Count - 1);
return(result);
}
public void RequestLost(int index, InactiveRequest request)
{
Console.WriteLine("{0},{1}", index, remaining.Count);
active[index].Remove(request);
remaining[index].Add(request);
remaining[index].Sort();
}
public InactiveRequest NewRequest(int index)
{
InactiveRequest newRequest = remaining[index][remaining[index].Count - 1];
remaining[index].RemoveAt(remaining[index].Count - 1);
active[index].Add(newRequest);
active[index].Sort();
return(newRequest);
}
/// <summary>
/// 为指定片断创建一个request 消息，返回的是一个二元组，例如（32k, 16k），表示“子片断”的起始位置是32k ，大小是16k。
/// </summary>
/// <param name="index">片断索引号</param>
/// <returns>返回第index个片断的起始位置最小的请求信息</returns>
public InactiveRequest NewRequest(int index)
{
//numActive[index]记录了已经为第index个片断发出的request数量。
numActive[index]++;
//totalInactive记录了尚没有发出request的子片断总的大小。
totalInactive--;
//从 inactiveRequest中移出最小的那个request（也就是起始位置最小）。
List <InactiveRequest> requests = inactiveRequests[index];
InactiveRequest minRequest = InactiveRequest.Min(requests);
requests.Remove(minRequest);
return(minRequest);
}
/// <summary>
/// 产生第index个片断的所有请求信息
/// </summary>
/// <param name="index">片断的索引号</param>
/// <param name="length">片断的长度</param>
private void MakeInactiveRequest(int index, int length)
{
List <InactiveRequest> requestList = inactiveRequests[index];
//子片断在片断的偏移位置
int offset;
int notLastLength = length - requestSize;
//添加每个子片断的请求信息
for (offset = 0; offset < notLastLength; offset += requestSize)
{
InactiveRequest request = new InactiveRequest(offset, requestSize);
requestList.Add(request);
totalInactive++;
}
//添加最后一个子片断的请求信息
InactiveRequest lastRequest = new InactiveRequest(offset, length - offset);
requestList.Add(lastRequest);
totalInactive++;
}
public void RequestLost(int index, InactiveRequest request)
{
}
public void FixDownload()
{
if (requests.Count == downloader.BackLog)
{
return;
}
int piece = downloader.PiecePicker.Next(this.Want);
if (piece == -1)
{
if (interested && requests.Count == 0)
{
interested = false;
connection.SendNotInterested();
}
}
else
{
if (!interested)
{
interested = true;
connection.SendInterested();
}
if (choked)
{
return;
}
bool hit = false;
while (piece != -1)
{
while (requests.Count < downloader.BackLog)
{
InactiveRequest inactiveRequest = downloader.StorageWrapper.NewRequest(piece);
downloader.PiecePicker.Requested(piece);
requests.Add(new ActiveRequest(piece, inactiveRequest.Begin, inactiveRequest.Length));
connection.SendRequest(piece, inactiveRequest.Begin, inactiveRequest.Length);
if (!downloader.StorageWrapper.DoIHaveRequests(piece))
{
hit = true;
break;
}
}
if (requests.Count == downloader.BackLog)
{
break;
}
piece = downloader.PiecePicker.Next(this.Want);
}
if (hit)
{
foreach (NormalSingleDownload download in downloader.Downloads)
{
download.FixDownload();
}
}
}
}
