Socket-Verbindung herstellen ohne zu blockieren

[KodeZwerg]

Hi, ich hab hier zwei Sources entdeckt die das Thema Socket+(multi)Thread aufgreifen, vielleicht ist etwas für Dich dabei?
connecting a server socket with several client sockets und TServerSocket in multithread mode

Mein Tipp wäre erstmal anpingen ob Server überhaupt existiert um Connected = true zu setzen.

edit
für alle dir nur source wollen, hier der aus link 1
Es kann gut möglich sein das in den Links noch Verbesserungen o.ä. erwähnt werden.

Delphi-Quellcode:

unit Server;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs, StdCtrls, Sockets, ServerThread;

type

  { TForm1 }

  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  public
    procedure handle(ID, message: String);
  end;

var
  Form1: TForm1;
  threads: Array[1..4] of TServerThread;
  serverSocket: Longint;
  clientSocket: Longint;
  serverAddr: TInetSockAddr;
  opt: Integer = 1;
  addrSize: Longint;
  clientCount: Integer = 0;

implementation

{$R *.lfm}

{ TForm1 }

procedure TForm1.Button1Click(Sender: TObject);
begin
  repeat
    serverSocket:= fpSocket(AF_INET, SOCK_STREAM, 0);
    if fpSetSockOpt(serverSocket, SOL_SOCKET, SO_REUSEADDR, @opt, sizeOf(opt)) = SOCKET_ERROR then showMessage('Server : Multi : ' + intToStr(socketError));
    if serverSocket = SOCKET_ERROR then showMessage('Server : Socket : ' + intToStr(socketError));
    serverAddr.sin_family:= AF_INET;
    serverAddr.sin_port:= htons(50000);
    serverAddr.sin_addr.s_addr:= htonl($7F000001);
    if fpBind(serverSocket, @serverAddr, sizeOf(serverAddr)) = SOCKET_ERROR then showMessage('Server : Bind : ' + intToStr(socketError));
    if fpListen(serverSocket, 4) = SOCKET_ERROR then showMessage('Server : Listen : ' + intToStr(socketError));
    showMessage('Waiting for connect from Client...');
    addrSize:= sizeOf(serverAddr);
    clientSocket:= fpaccept(serverSocket, @serverAddr, @addrSize);
    if clientSocket = SOCKET_ERROR then showMessage('Server : Accept : ' + intToStr(socketError)) else clientCount:= clientCount + 1;
    threads[clientCount]:= TServerThread.create(true, clientSocket);
    threads[clientCount].start;
  until clientCount = 4;
end;

procedure TForm1.handle(ID, message: String);
var
  i, toTerminate: Integer;
  MyCriticalSection: TRTLCriticalSection;
begin
  InitCriticalSection(MyCriticalSection);
  EnterCriticalSection(MyCriticalSection);
  try
    for i:= 1 to clientCount do
    begin
      threads.send(ID + ': ' + message);
      if threads.getID = ID then toTerminate:= i;
    end;
    if message = 'ciao' then
    begin
      threads[toTerminate].send('ciao');
      threads[toTerminate].close;
      clientCount:= clientCount - 1;
      for i:= toTerminate to clientCount do threads:= threads[i + 1];
    end;
  finally
    LeaveCriticalSection(MyCriticalSection);
  end;
end;

end.



unit ServerThread;

{$mode objfpc}{$H+}

interface

uses Classes, Dialogs, Sockets, SysUtils;

type
  TServerThread = class(TThread)
  private
    ID: String;
    clientSocket: Longint;
  protected
    procedure execute; override;
  public
    constructor create(createSuspended: Boolean; client: Longint);
    procedure send(msg: String);
    function getID: String;
    procedure close;
  end;

var
  buffer: String[255];
  count: Longint;

implementation

uses Server;

constructor TServerThread.create(createSuspended: Boolean; client: Longint);
begin
  freeOnTerminate:= true;
  inherited create(createSuspended);
  clientSocket:= client;
end;

procedure TServerThread.execute;
begin
  count:= fprecv(clientSocket, @buffer[1], 255, 0);
  if (count <> SOCKET_ERROR) and (count > 0) then
  begin
    setLength(buffer, count);
    ID:= buffer;
  end;
  buffer:= 'Herzlich willkommen im Chat, ' + ID;
  count:= length(buffer);
  if fpsend(clientSocket, @buffer[1], count, 0) = count then
  begin
    repeat
      count:= fprecv(clientSocket, @buffer[1], 255, 0);
      if (count <> SOCKET_ERROR) and (count > 0) then
      begin
        setLength(buffer, count);
        Form1.handle(ID, buffer);
      end;
    until (count = SOCKET_ERROR) or (count = 0);
  end;
end;

procedure TServerThread.send(msg: String);
begin
  fpsend(clientSocket, @msg[1], length(msg), 0);
end;

function TServerThread.getID: String;
begin
  result:= ID;
end;

procedure TServerThread.close;
begin
  closeSocket(clientSocket);
end;

end.



unit Client;

{$mode objfpc}{$H+}

interface

uses
  Classes, SysUtils, FileUtil, Forms, Controls, Graphics, Dialogs, StdCtrls, Sockets, ClientThread;

type

  { TForm1 }

  TForm1 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    Edit1: TEdit;
    Edit2: TEdit;
    Memo1: TMemo;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Edit1Change(Sender: TObject);
    procedure handle(msg: String);
  private
    { private declarations }
  public
    { public declarations }
  end;

var
  Form1: TForm1;
  thread: TClientThread;
  serverAddr: TInetSockAddr;
  serverSocket: Longint;

implementation

{$R *.lfm}

{ TForm1 }

procedure TForm1.Button1Click(Sender: TObject);
begin
  serverSocket:= fpSocket(AF_INET, SOCK_STREAM, 0);
  if serverSocket = SOCKET_ERROR then showMessage('Client : Socket : ' + intToStr(socketError));
  serverAddr.sin_family:= AF_INET;
  serverAddr.sin_port:= htons(50000);
  serverAddr.sin_addr.s_addr:= htonl($7F000001);
  //funktioniert beim zweiten Client nicht, da kein Error, obwohl die Verbindung nicht zustande kommt (fpaccept reagiert nicht)
  if fpconnect(serverSocket, @serverAddr, sizeOf(serverAddr)) = SOCKET_ERROR then showMessage('Client : Connect : ' + intToStr(socketError));
  thread:= TClientThread.create(true, serverSocket);
  thread.start;
  buffer:= Edit1.Text;
  fpsend(serverSocket, @buffer[1], length(buffer), 0);
  Button2.Enabled:= true;
end;

procedure TForm1.Button2Click(Sender: TObject);
var
  buffer: String;
begin
  buffer:= Edit2.Text;
  fpsend(serverSocket, @buffer[1], length(buffer), 0);
end;

procedure TForm1.Edit1Change(Sender: TObject);
begin
  if length(Edit1.Text) > 0 then Button1.Enabled:= true else Button1.Enabled:= false;
end;

procedure TForm1.handle(msg: String);
begin
  if msg = 'ciao' then closeSocket(serverSocket)
  else Memo1.Lines.Add(msg);
end;

end.



unit ClientThread;

{$mode objfpc}{$H+}

interface

uses Classes, Dialogs, Sockets, SysUtils;

type
  TClientThread = class(TThread)
  private
    serverSocket: Longint;
  protected
    procedure execute; override;
  public
    constructor create(createSuspended: Boolean; server: Longint);
  end;

var
  buffer: String[255];
  count, i: Longint;

implementation

uses Client;

constructor TClientThread.create(createSuspended: Boolean; server: Longint);
begin
  freeOnTerminate:= true;
  inherited create(createSuspended);
  serverSocket:= server;
end;

procedure TClientThread.execute;
begin
  repeat
    count:= fprecv(serverSocket, @buffer[1], 255, 0);
    if count <> SOCKET_ERROR then
    begin
      setLength(buffer, count);
      Form1.handle(buffer);
    end;
  until buffer = 'ciao';
  closeSocket(serverSocket);
end;

end.

hier der aus link 2

Delphi-Quellcode:

program server;

uses
  Forms,
  main in 'main.pas' {Form1};

{$R *.RES}

begin
  Application.Initialize;
  Application.CreateForm(TForm1, Form1);
  Application.Run;
end.


/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\


 Unit main;

Interface

Uses
  Windows, SysUtils, Messages, Classes, Forms, ScktComp, Controls, StdCtrls,
  Menus, Mask, Spin, ComCtrls, ExtCtrls;

Const
  CM_IncCount = WM_USER + 1;

Type
  TForm1 = Class(TForm)
    ServerSocket: TServerSocket;
    MainMenu: TMainMenu;
    File1: TMenuItem;
    ActiveItem: TMenuItem;
    N1: TMenuItem;
    Exit1: TMenuItem;
    Panel1: TPanel;
    Label1: TLabel;
    CacheEdit: TSpinEdit;
    Label2: TLabel;
    PortEdit: TSpinEdit;
    Label3: TLabel;
    ThreadCount: TEdit;
    Panel2: TPanel;
    ListBox1: TListBox;
    Panel3: TPanel;
    StatusBar1: TStatusBar;
    CharCount: TLabel;
    Procedure ServerSocketGetThread(Sender: TObject;
      ClientSocket: TServerClientWinSocket;
      Var SocketThread: TServerClientThread);
    Procedure FormCreate(Sender: TObject);
    Procedure FormClose(Sender: TObject; Var Action: TCloseAction);
    Procedure Exit1Click(Sender: TObject);
    Procedure PortEditChange(Sender: TObject);
    Procedure ActiveItemClick(Sender: TObject);
    Procedure ServerSocketThreadEnd(Sender: TObject;
      Thread: TServerClientThread);
    Procedure ServerSocketThreadStart(Sender: TObject;
      Thread: TServerClientThread);
    Procedure CacheEditChange(Sender: TObject);
  protected
    Procedure CMIncCount(Var Msg: TMessage); message CM_IncCount;
  public
  End;

{ TFileServerThread }

  TFileServerThread = Class(TServerClientThread)
  public
    Procedure ClientExecute; override;
  End;

Var
  Form1: TForm1;

Implementation

{$R *.DFM}

{ TFileServerThread }

Procedure TFileServerThread.ClientExecute;
Var
  Data: Array[0..1023] Of char;
  RecText: String;
  SocketStream: TWinSocketStream;
Begin
  While Not Terminated And ClientSocket.Connected Do
  Try
    SocketStream := TWinSocketStream.Create(ClientSocket, 30000);
    Try
      FillChar(Data, SizeOf(Data), 0);
      If SocketStream.Read(Data, SizeOf(Data)) = 0 Then
      Begin
        // If we didn't get any data after xx seconds then close the connection
        ClientSocket.SendText('Timeout on Server'+#13#10);
        //Wait a little time to allow sending of text before disconnect
        sleep(1);
        ClientSocket.Close;
        Terminate;
      End;
      RecText := Data;
      If Length(RecText) > 2 Then
        Delete(RecText, Pos(#13#10, RecText), 2); // Delete 10
      If ClientSocket.Connected Then
      Begin
        ClientSocket.SendText(RecText);
        SendMessage(Form1.Listbox1.Handle, LB_ADDSTRING, 0, Integer(PChar(RecText)));
        PostMessage(Form1.Handle, CM_INCCOUNT, 0, 0);
      End;
    Finally
      SocketStream.Free;
    End;
  Except
    HandleException;
  End;
End;

Procedure TForm1.ServerSocketGetThread(Sender: TObject;
  ClientSocket: TServerClientWinSocket;
  Var SocketThread: TServerClientThread);
Begin
  // Create a new thread for connection
  SocketThread := TFileServerThread.Create(False, ClientSocket);
  ClientSocket.SendText('Welcome to Server'+#13#10);
End;

Procedure TForm1.FormCreate(Sender: TObject);
Begin
  CacheEdit.Value := ServerSocket.ThreadCacheSize;
  PortEdit.Value := ServerSocket.Port;
  CharCount.Caption := '0';
  ActiveItemClick(Nil);
End;

Procedure TForm1.FormClose(Sender: TObject; Var Action: TCloseAction);
Begin
  ServerSocket.Close;
End;

Procedure TForm1.CMIncCount(Var Msg: TMessage);
Begin
  CharCount.Caption := IntToStr(StrToInt(CharCount.Caption) + 1);
End;

Procedure TForm1.Exit1Click(Sender: TObject);
Begin
  Close;
End;

Procedure TForm1.PortEditChange(Sender: TObject);
Begin
  ServerSocket.Port := StrToInt(PortEdit.Text);
End;

Procedure TForm1.ActiveItemClick(Sender: TObject);
Begin
  ServerSocket.Active := Not ServerSocket.Active;
  ActiveItem.Checked := ServerSocket.Active;
  If ServerSocket.Active Then
    StatusBar1.SimpleText := 'Active'
  Else
    StatusBar1.SimpleText := 'InActive';
End;

Procedure TForm1.ServerSocketThreadEnd(Sender: TObject;
  Thread: TServerClientThread);
Begin
  ThreadCount.Text := IntToStr(StrToInt(ThreadCount.Text) - 1);
End;

Procedure TForm1.ServerSocketThreadStart(Sender: TObject;
  Thread: TServerClientThread);
Begin
  ThreadCount.Text := IntToStr(StrToInt(ThreadCount.Text) + 1);
End;

Procedure TForm1.CacheEditChange(Sender: TObject);
Begin
  ServerSocket.ThreadCacheSize := CacheEdit.Value;
End;

End.

[Medium]

Die Idee die Verbindung im Thread erstmal anzutesten gefällt mir! Zwar nicht das schönste von der Welt, aber ich brauche in diesem Falle leider das mit dem geringsten Aufwand. (Das Programm ist eh heillos verloren was Wartbarkeit angeht - da muss ich beizeiten mal eine Renovierung anbieten...) Das probiere ich mal!

Ich hatte zwischenzeitlich einfach mal probiert bloß das ".Active := true" in einem Thread zu machen, und dabei ist mir das komplette Programm mit den wildestens Meldungen und manchmal auch gar keinen auf etliche Weisen um die Ohren geflogen . Es hilft vermutlich auch nicht, dass ich in den Event-Handlern reichlich Dinge im UI mache. (Ich vermute mal, dass die dann nämlich auch auf einmal im Thread-Kontext landen.)

[Mavarik]

Zitat von KodeZwerg:

Hi, ich hab hier zwei Sources entdeckt die das Thema Socket+(multi)Thread aufgreifen, vielleicht ist etwas für Dich dabei?

[OT]
Nicht das ich einen guten Source-Code nicht zu schätzen wüsste, aber :

Du kannst den Source auch als File ins Posting bringen und vielleicht dann einzelne rauskopieren, falls Du dazu einen Kommentar anbringen möchtest.

Auf jeden Fall vorher mal einen DelphiSource-Formatter drüber laufen lassen, besonders wenn es so gruselige One-Liner sind.
[/OT]

Zum Thema... Eine UPD/TCP Socket inkl. asynchroner Verarbeitung kann man über die Windows API. in unter 400 LOC implementieren...

Hierzu würde diesen Link empfehlen. (Auch wenn der Sourcelink in diesem Artikel nicht richtig funktioniert - man kann es so runter tippen).

Mavarik