IdICMPClient unter Vista: Fehler bei Bereichsprüfung

[seim]

Ok ich hab' den Weg über die ICMP.dll genommen..

Aufruf:

Delphi-Quellcode:

procedure TForm1.BtnClick(lala)
begin
if Ping('127.0.0.1') then
ShowMessage('Dein PC ist an')
else
ShowMessage('Dein PC scheint aus zu sein');
end;

Types und Vars:

Delphi-Quellcode:

type
  //ICMP.dll Datentypen
  TSunB = packed record
    s_b1, s_b2, s_b3, s_b4: byte;
  end;

  TSunW = packed record
    s_w1, s_w2: word;
  end;

  PIPAddr = ^TIPAddr;

  TIPAddr = record
    case integer of
      0: (S_un_b: TSunB);
      1: (S_un_w: TSunW);
      2: (S_addr: longword);
  end;

  IPAddr = TIPAddr; //Eine der Funktionen in icmp.dll braucht den Datentyp "IPAddr"

  ip_option_information = record
    Ttl : byte;
    Tos : byte;
    Flags : byte;
    OptionsSize : byte;
    OptionsData : pointer;
  end;

  ICMP_ECHO_REPLY = record
    Address : IPAddr;
    Status : ULONG;
    RoundTripTime : ULONG;
    DataSize : Word;
    Reserved : Word;
    Data : Pointer;
    Options : IP_OPTION_INFORMATION;
  end;

//ICMP.dll Declarations
function IcmpCreateFile : THandle; stdcall; external 'icmp.dll';
function IcmpCloseHandle (icmpHandle : THandle) : boolean; stdcall; external 'icmp.dll';
function IcmpSendEcho (IcmpHandle : THandle; DestinationAddress : IPAddr;
    RequestData : Pointer; RequestSize : Smallint;
    RequestOptions : pointer;
    ReplyBuffer : Pointer;
    ReplySize : DWORD;
    Timeout : DWORD) : DWORD; stdcall; external 'icmp.dll';

Funktionen:

Delphi-Quellcode:

function Fetch(var AInput: string; const ADelim: string = ' '; const ADelete: Boolean = true): string;
var
  iPos: Integer;
begin
  if ADelim = #0 then begin
    // AnsiPos does not work with #0
    iPos := Pos(ADelim, AInput);
  end else begin
    iPos := Pos(ADelim, AInput);
  end;
  if iPos = 0 then begin
    Result := AInput;
    if ADelete then begin
      AInput := '';
    end;
  end else begin
    result := Copy(AInput, 1, iPos - 1);
    if ADelete then begin
      Delete(AInput, 1, iPos + Length(ADelim) - 1);
    end;
  end;
end;

procedure TranslateStringToTInAddr(AIP: string; var AInAddr);
var
  phe: PHostEnt;
  pac: PChar;
  GInitData: TWSAData;
begin
  WSAStartup($101, GInitData);
  try
    phe := GetHostByName(PChar(AIP));
    if Assigned(phe) then
    begin
      pac := phe^.h_addr_list^;
      if Assigned(pac) then
      begin
        with TIPAddr(AInAddr).S_un_b do begin
          s_b1 := Byte(pac[0]);
          s_b2 := Byte(pac[1]);
          s_b3 := Byte(pac[2]);
          s_b4 := Byte(pac[3]);
        end;
      end
      else
      begin
        raise Exception.Create('Error getting IP from HostName');
      end;
    end
    else
    begin
      raise Exception.Create('Error getting HostName');
    end;
  except
    FillChar(AInAddr, SizeOf(AInAddr), #0);
  end;
  WSACleanup;
end;

function Ping(InetAddress : string) : boolean;
var
 Handle : THandle;
 InAddr : IPAddr;
 DW     : DWORD;
 PingBuf: array[0..31] of char;
 Reply  : ICMP_ECHO_REPLY;
begin
  result := false;

  Handle := IcmpCreateFile;

  if Handle = INVALID_HANDLE_VALUE then
   Exit;

  TranslateStringToTInAddr(InetAddress, InAddr);

  Reply.Data := @pingBuf;
  Reply.DataSize := 32;

  DW := IcmpSendEcho(Handle, InAddr, @PingBuf, 32, nil, @reply, SizeOf(icmp_echo_reply) + 32 , 1000); //Die 1000 gibt den TimeOut an

  if DW <> 0 then
    Result:= true;

  IcmpCloseHandle(Handle);
end;

[stoxx]

Zitat von seim:

Ok ich hab' den Weg über die ICMP.dll genommen..


Funktionen:

Delphi-Quellcode:

  ....
  TranslateStringToTInAddr(InetAddress, InAddr);

  Reply.Data := @pingBuf;
  Reply.DataSize := 32;

  DW := IcmpSendEcho(Handle, InAddr, @PingBuf, 32, nil, @reply, SizeOf(icmp_echo_reply) + 32 , 1000); //Die 1000 gibt den TimeOut an

  if DW <> 0 then
    Result:= true;

  IcmpCloseHandle(Handle);
end;

Hi .. die Unit ist schick, hat aber leider einen kleinen Fehler.
Trotz abgezogenem Netzwerkkabel liefert die Funktion (manchmal) ein True zurück.
Nach stöbern im msdn hat sich herausgestellt, dass man den Rückgabewert nicht so behandeln darf.

so ist es korrekt:

Delphi-Quellcode:

const

  IP_SUCCESS                  = 0;
  IP_BUF_TOO_SMALL            = 11001;
  IP_DEST_NET_UNREACHABLE     = 11002;
  IP_DEST_HOST_UNREACHABLE    = 11003;
  IP_DEST_PROT_UNREACHABLE    = 11004;
  IP_DEST_PORT_UNREACHABLE    = 11005;
  IP_NO_RESOURCES             = 11006;
  IP_BAD_OPTION               = 11007;
  IP_HW_ERROR                 = 11008;
  IP_PACKET_TOO_BIG           = 11009;
  IP_REQ_TIMED_OUT            = 11010;
  IP_BAD_REQ                  = 11011;
  IP_BAD_ROUTE                = 11012;
  IP_TTL_EXPIRED_TRANSIT      = 11013;
  IP_TTL_EXPIRED_REASSEM      = 11014;
  IP_PARAM_PROBLEM            = 11015;
  IP_SOURCE_QUENCH            = 11016;
  IP_OPTION_TOO_BIG           = 11017;
  IP_BAD_DESTINATION          = 11018;
  IP_GENERAL_FAILURE          = 11050;




  ....

function Ping(InetAddress : string; var ErrorMessage : String) : boolean;
var
 Handle : THandle;
 InAddr : IPAddr;
 DW : DWORD;
 PingBuf: array[0..31] of char;
 Reply : ICMP_ECHO_REPLY;
begin
  result := false;
  ErrorMessage := '';
  try
      DW := 0;
      Handle := IcmpCreateFile;
      if Handle = INVALID_HANDLE_VALUE then
       Exit;
      try
        TranslateStringToTInAddr(InetAddress, InAddr);
      except
        on E: Exception do begin
          ErrorMessage :=  e.Message;
          Exit;
        end;
      end;
      Reply.Status := IP_SUCCESS;
      Reply.Data := @pingBuf;
      Reply.DataSize := 32;
      DW := IcmpSendEcho(Handle, InAddr, @PingBuf, 32, nil, @reply, SizeOf(icmp_echo_reply) + 32 , 1500); //Die 1000 gibt den TimeOut an

      // if (Reply.Status <> IP_GENERAL_FAILURE) and (Reply.Status <> IP_SUCCESS) then
      //    ErrorMessage :=  Get_ICMP_ECHO_REPLY_StateString(reply.Status);
         
      
      if DW <> 0 then begin

          if Reply.Status = IP_SUCCESS then begin
               Result := True;
               ErrorMessage := '';
          end;
      end;
  except
  end;
  IcmpCloseHandle(Handle);
end;   // Ping