sync: restore source from Google Drive

vendor/kam_remake/src/net/KM_NetUDP.pas

@@ -0,0 +1,229 @@
+unit KM_NetUDP;
+{$I KaM_Remake.inc}
+interface
+uses
+  Classes, Math, SysUtils, KM_CommonClasses, KM_Defaults
+  {$IFDEF WDC} ,KM_NetUDPOverbyte {$ENDIF}
+  {$IFDEF FPC} ,KM_NetUDPLNet {$ENDIF}
+  ;
+
+
+type
+  TNotifyServerDetectedEvent = procedure(const aAddress: string; const aPort: Word; const aName: string) of object;
+
+  TKMNetUDP = class
+  private
+    {$IFDEF WDC} fUDP: TKMNetUDPOverbyte; {$ENDIF}
+    {$IFDEF FPC} fUDP: TKMNetUDPLNet;     {$ENDIF}
+
+    fOnError: TGetStrProc;
+    procedure HandleReceive(const aAddress: string; aData: Pointer; aLength: Cardinal); virtual; abstract;
+    procedure HandleError(const aMsg: string);
+  protected
+    fScanPort: Word;
+  public
+    constructor Create(aScanPort: Word);
+    destructor Destroy; override;
+    procedure UpdateStateIdle;
+    property OnError: TGetStrProc write fOnError;
+  end;
+
+  TKMNetUDPAnnounce = class(TKMNetUDP)
+  private
+    fServerName: AnsiString;
+    fGamePort: Word;
+    procedure HandleReceive(const aAddress: string; aData: Pointer; aLength: Cardinal); override;
+  public
+    procedure StartAnnouncing(const aGamePort: Word; const aName: AnsiString; aAnnounce: Boolean);
+    procedure StopAnnouncing;
+    procedure UpdateSettings(const aName: AnsiString; aScanPort: Word);
+  end;
+
+  TKMNetUDPScan = class(TKMNetUDP)
+  private
+    fOnServerDetected: TNotifyServerDetectedEvent;
+    procedure HandleReceive(const aAddress: String; aData: Pointer; aLength: Cardinal); override;
+  public
+    procedure ScanForServers;
+    procedure TerminateScan;
+    property OnServerDetected: TNotifyServerDetectedEvent write fOnServerDetected;
+  end;
+
+
+implementation
+
+
+{ TKMNetUDP }
+constructor TKMNetUDP.Create(aScanPort: Word);
+begin
+  inherited Create;
+  {$IFDEF WDC} fUDP := TKMNetUDPOverbyte.Create; {$ENDIF}
+  {$IFDEF FPC} fUDP := TKMNetUDPLNet.Create;     {$ENDIF}
+  fScanPort := aScanPort;
+  fUDP.OnError := HandleError;
+  fUDP.OnRecieveData := HandleReceive;
+end;
+
+
+destructor TKMNetUDP.Destroy;
+begin
+  fUDP.Free;
+
+  inherited;
+end;
+
+
+procedure TKMNetUDP.HandleError(const aMsg: String);
+begin
+  if Assigned(fOnError) then fOnError(aMsg);
+end;
+
+
+procedure TKMNetUDP.UpdateStateIdle;
+begin
+  {$IFDEF FPC} fUDP.UpdateStateIdle; {$ENDIF}
+end;
+
+
+{ TKMNetUDPAnnounce }
+procedure TKMNetUDPAnnounce.StartAnnouncing(const aGamePort: Word; const aName: AnsiString; aAnnounce: Boolean);
+begin
+  fServerName := aName;
+  fGamePort := aGamePort;
+  fUDP.StopListening;
+  if aAnnounce then
+    try
+      fUDP.Listen(SERVER_DEFAULT_UDP_ANNOUNCE_PORT);
+    except
+      //UDP announce is not that important, and will fail whenever you start more than 1 server per machine
+      on E: Exception do
+        if Assigned(fOnError) then fOnError('UDP listen for local server detection failed to start: ' + E.Message);
+    end;
+end;
+
+
+procedure TKMNetUDPAnnounce.StopAnnouncing;
+begin
+  fUDP.StopListening;
+end;
+
+
+procedure TKMNetUDPAnnounce.UpdateSettings(const aName: AnsiString; aScanPort: Word);
+begin
+  fServerName := aName;
+  fScanPort := aScanPort;
+end;
+
+
+procedure TKMNetUDPAnnounce.HandleReceive(const aAddress: string; aData: Pointer; aLength: Cardinal);
+var
+  M: TKMemoryStream;
+  S: AnsiString;
+begin
+  M := TKMemoryStreamBinary.Create;
+  try
+    M.WriteBuffer(aData^, aLength);
+    M.Position := 0;
+
+    //Check header
+    M.ReadA(S);
+    if S <> 'KaM Remake' then Exit;
+    M.ReadA(S);
+    if S <> NET_PROTOCOL_REVISON then Exit;
+
+    //Only care about scan packets
+    M.ReadA(S);
+    if S <> 'scan' then Exit;
+
+    //Send a response to this scanner
+    M.Free;
+    M := TKMemoryStreamBinary.Create;
+    M.WriteA('KaM Remake');
+    M.WriteA(NET_PROTOCOL_REVISON);
+    M.WriteA('announce');
+    M.Write(fGamePort);
+    M.WriteA(fServerName);
+
+    fUDP.SendPacket(aAddress, fScanPort, M.Memory, M.Size);
+  finally
+    M.Free;
+  end;
+end;
+
+
+{ TKMNetUDPDetect }
+procedure TKMNetUDPScan.ScanForServers;
+var
+  M: TKMemoryStream;
+begin
+  //Prepare to receive responses
+  fUDP.StopListening;
+  try
+    fUDP.Listen(fScanPort);
+  except
+    //UDP scan is not that important, and could fail during debugging if running two KaM Remake instances
+    on E: Exception do
+    begin
+      if Assigned(fOnError) then fOnError('UDP scan failed to listen: ' + E.Message);
+      Exit;
+    end;
+  end;
+
+  M := TKMemoryStreamBinary.Create;
+  try
+    M.WriteA('KaM Remake');
+    M.WriteA(NET_PROTOCOL_REVISON);
+    M.WriteA('scan');
+    try
+      //Broadcast
+      fUDP.SendPacket('255.255.255.255', 56789, M.Memory, M.Size);
+    except
+      on E: Exception do
+      begin
+        if Assigned(fOnError) then fOnError('UDP broadcast failed: ' + E.Message);
+        Exit;
+      end;
+    end;
+  finally
+    M.Free;
+  end;
+end;
+
+
+procedure TKMNetUDPScan.TerminateScan;
+begin
+  fUDP.StopListening;
+end;
+
+
+procedure TKMNetUDPScan.HandleReceive(const aAddress: String; aData: Pointer; aLength: Cardinal);
+var
+  M: TKMemoryStream;
+  S, ServerName: AnsiString;
+  serverPort: Word;
+begin
+  M := TKMemoryStreamBinary.Create;
+  try
+    M.WriteBuffer(aData^, aLength);
+    M.Position := 0;
+
+    M.ReadA(S);
+    if S <> 'KaM Remake' then Exit;
+    M.ReadA(S);
+    if S <> NET_PROTOCOL_REVISON then Exit;
+    //Only care about announce packets
+    M.ReadA(S);
+    if S <> 'announce' then Exit;
+
+    //Read the server's game port and report it
+    M.Read(serverPort);
+    M.ReadA(ServerName);
+    fOnServerDetected(aAddress, serverPort, UnicodeString(ServerName));
+  finally
+    M.Free;
+  end;
+end;
+
+
+end.
+