Hi everyone,
I'm new to the world of winsock apps and am getting the dreaded error 10054 -
Connection Reset by Peer.
I'm using the Synapse TTCPBlockSocket component.
At the moment I'm just trying to send a text message from client to server, and
have the server display the message in the main thread VCL GUI.
Since the ultimate aim is to perform memory-intensive graphical manipulations in
response to a client request, I have designed the server application to have a
listening thread that then Synchronizes back to the main VCL thread to perform
the actual communication. I know that most designs (eg: "Echo") will instead
spawn a worker thread, but I want to serialize "sessions" to maximize available
memory, and also because of the graphical manipulations, which I understand can
only be performed in the main VCL thread anyway.
My client code is:
procedure TClientForm.ConnectActionExecute(Sender: TObject);
var
Sock: TTCPBlockSocket;
begin
Sock := blcksock.TTCPBlockSocket.Create;
Sock.CreateSocket; // does nothing ?
Sock.SetLinger(true, 10);
Sock.Connect(ServerEdit.Text, PortNEdit.Text);
if (Sock.LastError = 0) then
begin
Sock.SendString('Hello Server !');
SendMemo.Lines.Add('Hello Server !');
end else begin
ShowMessageFmt('Internet Communication Error' + #13#10#13#10 + '%s',
[Sock.LastErrorDesc]);
end;
Sock.CloseSocket;
Sock.Free;
end;
and my relevant server code is:
ServerDaemon := TTCPServerDaemon.Create;
ServerDaemon.SynchMethod := SynchMethod;
ServerDaemon.Port := PortNEdit.Text;
...
procedure TTCPServerDaemon.Execute;
begin
FSock.CreateSocket;
FSock.SetLinger(true, 10);
FSock.Bind('0.0.0.0', Self.Port);
FSock.Listen;
repeat
if Self.Terminated then break;
if FSock.CanRead(1000) then
begin
FClientSock := 0;
FClientSock := FSock.Accept;
if (FSock.LastError = 0) and Assigned(SynchMethod) then
Synchronize(SynchMethod);
// = jump back to main VCL thread to grab data and perform calculations
end;
until false;
end;
...
procedure TServerForm.SynchMethod;
var
Sock : TTCPBlockSocket;
Str: String;
begin
ReceiveMemo.Lines.Add('We got hit !');
Sock := TTCPBlockSocket.Create;
KillConnectionBitBtn.Tag := 0;
KillConnectionBitBtn.Enabled := TRUE;
try
Sock.Socket := ServerDaemon.ClientSock; // yes, it gets a valid socket, 1668
Sock.GetSins;
{FSock.LocalSin = (2, 2, 49425, (('', #0, #0, #1), (127, 256), 16777343), (#0,
#0, #0, #0, #0, #0, #0, #0), 49425, 16777343, ((#0, #0, #0, #0, #0, #0, #0, #0,
#0, #0, #0, #0, #0, #0, #0, #0), (0, 0, 0, 0, 0, 0, 0, 0), (0, 0, 0, 0)), 0)
FSock.RemoteSin = (2, 2, 6929, (('', #0, #0, #1), (127, 256), 16777343), (#0,
#0, #0, #0, #0, #0, #0, #0), 6929, 16777343, ((#0, #0, #0, #0, #0, #0, #0, #0,
#0, #0, #0, #0, #0, #0, #0, #0), (0, 0, 0, 0, 0, 0, 0, 0), (0, 0, 0, 0)), 0)}
repeat
Application.ProcessMessages;
if (KillConnectionBitBtn.Tag > 0) then
break;
Str := Sock.RecvString(ReadTimeoutNEdit.AsInteger);
ReceiveMemo.Lines.Add(Str);
if (Sock.LastError <> 0) then
begin
ShowMessageFmt('Internet Communication Error' + #13#10#13#10 + '%s',
[Sock.LastErrorDesc]);
break;
end;
until false;
finally
Sock.Free;
KillConnectionBitBtn.Enabled := FALSE;
KillConnectionBitBtn.Tag := 0;
end;
end;
Any hints on how to progress this problem would be greatly appreciated,
Thanks in advance,
Mat
