//public static bool TryRead(this Stream stream, byte[] buffer, int offset, int count, out int bytesRead)
//{
// bool successful = true;
// int read = 0;
// try
// {
// read = stream.Read(buffer, offset, count);
// }
// catch (Exception)
// {
// successful = false;
// }
// bytesRead = read;
// return successful;
//}
//public static bool TryWrite(this Stream stream, byte[] buffer, int offset, int count)
//{
// bool successful = true;
// try
// {
// stream.Write(buffer, offset, count);
// }
// catch (Exception)
// {
// successful = false;
// }
// return successful;
//}
/// <summary>
/// 从指定的 <see cref="System.IO.Stream"/> 中读取一条消息。
/// </summary>
/// <param name="stream">要读取的 <see cref="System.IO.Stream"/>。</param>
/// <param name="message">读取出的消息。如果返回值不是 <see cref="Kei.KNetwork.MessageIOErrorCode.NoError"/>，则该值无效。</param>
/// <returns>一个 <see cref="Kei.KNetwork.MessageIOCode"/> 值，表示读取的结果。</returns>
public static MessageIOErrorCode ReadMessage(this Stream stream, out KMessage message)
{
byte[] buffer;
KMessage km = new KMessage();
// Check magic
try
{
buffer = new byte[8];
stream.Read(buffer, 0, 8);
km.MagicNumber = BitConverter.ToUInt64(buffer, 0);
if (km.MagicNumber != KMessage.Magic)
{
message = km;
return(MessageIOErrorCode.WrongMagicNumber);
}
}
catch (Exception)
{
message = km;
return(MessageIOErrorCode.ReadMagicNumberFailed);
}
// Read header
try
{
var headerSize = Marshal.SizeOf(typeof(KMessageHeader));
buffer = new byte[headerSize];
stream.Read(buffer, 0, headerSize);
km.Header = KMessageHeader.FromByteArray(buffer);
}
catch (Exception)
{
message = km;
return(MessageIOErrorCode.ReadHeaderFailed);
}
// Read content
try
{
KMessageContent content = new KMessageContent();
buffer = new byte[4];
stream.Read(buffer, 0, 4);
content.DataLength = BitConverter.ToUInt32(buffer, 0);
content.Data = new byte[content.DataLength];
if (content.DataLength > 0)
{
stream.Read(content.Data, 0, (int)content.DataLength);
}
km.Content = content;
}
catch (Exception)
{
message = km;
return(MessageIOErrorCode.ReadContentFailed);
}
message = km;
return(MessageIOErrorCode.NoError);
}
/// <summary>
/// 生成一个 ClientEnterNetwork 消息。
/// </summary>
/// <param name="localEP">消息源的端点。</param>
/// <param name="realPort">非零表示这是接入点要连接接入点，该端口是本机正在监听的端口；零表示只是普通用户连接接入点。</param>
/// <returns>创建的 ClientEnterNetwork 消息。</returns>
public static KMessage ClientEnterNetwork(KEndPoint localEP, ushort realPort)
{
var message = KMessage.CreateEmptyMessage();
message.Header.Code = KMessageCode.ClientEnterNetwork;
message.Header.SourceEndPoint = localEP;
message.Header.MessageID = GetMessageHash();
BEncodedDictionary data = new BEncodedDictionary();
data.Add("message handled", 0);
data.Add("real port", realPort);
message.Content = KMessageContent.FromByteArray(data.Encode());
return(message);
}
/// <summary>
/// 生成一个 GotPeer 消息。
/// </summary>
/// <param name="localEP">消息源的端点。</param>
/// <param name="infoHash">用户所持有的 InfoHash。</param>
/// <param name="bitTorrentClientPort">用户所监听的端口（即 BitTorrent 客户端的监听端口）。</param>
/// <returns>创建的 GotPeer 消息。</returns>
public static KMessage GotPeer(KEndPoint localEP, InfoHash infoHash, ushort bitTorrentClientPort)
{
var message = KMessage.CreateEmptyMessage();
message.Header.Code = KMessageCode.GotPeer;
message.Header.SourceEndPoint = localEP;
message.Header.MessageID = GetMessageHash();
BEncodedDictionary data = new BEncodedDictionary();
data.Add("infohash", infoHash.ToByteArray());
data.Add("bt client port", bitTorrentClientPort);
message.Content = KMessageContent.FromByteArray(data.Encode());
return(message);
}
