TClientSocket和线程

Question

好了，伙计们，我使用TClientSocket类和线程来同时处理一系列主机。这一切都很好，但我开始注意到，过了一段时间，所有线程都被塞进了一个ReceiveBuf调用中……如果我打开10个线程，例如检查100个主机，它将开始良好，但在一段时间后，所有线程都将被阻塞，因为由于某些原因，一些主机不能很好地响应这个ReceiveBuf调用……我尝试执行ReceiveLength并检查接收是否> 0，以调用ReceiveBuf，但仍然不起作用。我将发布以下原始代码：

function Threads.ReceiveProtocolVersion;
var
   ProtocolVersion: array[0..11] of AnsiChar;
begin
 try
    MySocket.Socket.ReceiveBuf(ProtocolVersion, SizeOf(ProtocolVersion));
    Version:= AnsiString(ProtocolVersion);
   ...//continues but doesn't matter because many threads get stucked in the ReceiveBuf call...
 except
    Terminate; //we terminate thread if raise some exception..

好的，经过一些研究之后，我开始尝试这样做：

function Threads.ReceiveProtocolVersion;
var
   ProtocolVersion: array[0..11] of AnsiChar;
   SizeBuf: integer;
begin
 try
    SizeBuf:= MySocket.Socket.ReceiveLength;
    if SizeBuf > 0 then
     begin
       MySocket.Socket.ReceiveBuf(ProtocolVersion, SizeOf(ProtocolVersion));
       Version:= AnsiString(ProtocolVersion);
        ....
     end;
 except
    Terminate; //we terminate thread if raise some exception..

显然，它解决了线程在ReceiveBuf调用中被阻塞的问题，但由于某种未知的原因，没有线程(即使是那些工作正常的线程)进入“if SizeBuf >0”。有什么帮助吗？

//编辑显示更多线程代码：：Thread.Execute如下所示：

procedure MyThread.Execute;
begin
  while not(Terminated) do
    begin
      if SocketConnect then
        begin
          if ReceiveProtocolVersion then
           begin
              DoAuthentication;
            end;
         end;
          MySocket.Close;
          MySocket.Free;
    end;
    Terminate;
end;

SocketConnect函数为：

function MyThread.SocketConnect: bool;
begin
  Result:= false;
  MySocket:= TClientSocket.Create(Nil);
  MySocket.Port:= StrToInt(Form1.Edit1.Text);
  MySocket.ClientType:= ctBlocking;
  MySocket.Host:= Host; //Host is a private variable for thread class
  try
    MySocket.Active:= true;
    if (MySocket.Socket.Connected = true) then
      Result:= true;
  except
    Terminate;
  end;
end;

Answer 1

我使用TWinSocketStream解决了这个问题。如下所示：

function MyThread.CheckProtocol: bool;
var
  SockStream: TWinSocketStream;
  ProtocolVersion: array[0..11] of AnsiChar;
begin
 try
    SockStream := TWinSocketStream.Create(MySocket.Socket, 3000);
    SockStream.Read(ProtocolVersion, SizeOf(ProtocolVersion));
    RFBVer:= AnsiString(ProtocolVersion);
    ....

我读到使用阻塞模式套接字的正确方法是在DocWiki Embarcadero中通过TWinSocketStream发送/接收数据

无论如何，感谢那些试图帮助我们的人！