Close running version of program before installing update (Inno Setup)

Question

This should be simple, I need to stop any previous version of my program from running when the installer starts.

Most people suggested making an exe wh

Answer 1

If you are happy to write your own DLL, you can use the tool help API for TlHelp32.pas to determine what applications are running, and then get a window handle for them using EnumWindows, then send a WM_CLOSE to the window handle.

It's a bit of a pain, but it should work: I have some utility wrapper classes I developed with a friend a while back. Can't remember if we based it on someone else's code.

TWindows.ProcessISRunning and TWindows.StopProcess may help.

interface

uses
  Classes,
  Windows,
  SysUtils,
  Contnrs,
  Messages;

type


TProcess = class(TObject)
  public
    ID: Cardinal;
    Name: string;
end;

TWindow = class(TObject)
  private
    FProcessID: Cardinal;
    FProcessName: string;
    FHandle: THandle;
    FProcessHandle : THandle;
    function GetProcessHandle: THandle;
    function GetProcessID: Cardinal;
    function GetProcessName: string;
  public
    property Handle : THandle read FHandle;
    property ProcessName : string read GetProcessName;
    property ProcessID : Cardinal read GetProcessID;
    property ProcessHandle : THandle read GetProcessHandle;
end;

TWindowList = class(TObjectList)
  private
    function GetWindow(AIndex: Integer): TWindow;
  protected

  public
    function Add(AWindow: TWindow): Integer; reintroduce;
    property Window[AIndex: Integer]: TWindow read GetWindow; default;
end;

TProcessList = class(TObjectList)
  protected
    function GetProcess(AIndex: Integer): TProcess;
  public
    function Add(AProcess: TProcess): Integer; reintroduce;
    property Process[AIndex: Integer]: TProcess read GetProcess; default;
end;

TWindows = class(TObject)
  protected
  public
    class function GetHWNDFromProcessID(ProcessID: Cardinal; BuildList: Boolean = True): THandle;
    class function GetProcessList: TProcessList;
    class procedure KillProcess(ProcessName: string);
    class procedure StopProcess(ProcessName: string);
    class function ExeIsRunning(ExeName: string): Boolean;
    class function ProcessIsRunning(PID: Cardinal): Boolean;
end;

implementation

uses
  Forms,
  Math,
  PSAPI,
  TlHelp32;

const
  cRSPUNREGISTERSERVICE = 0;
  cRSPSIMPLESERVICE = 1;

type

TProcessToHWND = class(TObject)
  public
    ProcessID: Cardinal;
    HWND: Cardinal;
end;

function RegisterServiceProcess(dwProcessID, dwType: DWord): DWord; stdcall; external 'KERNEL32.DLL';
function GetDiskFreeSpaceEx(lpDirectoryName: PChar;
  var lpFreeBytesAvailableToCaller, lpTotalNumberOfBytes: TLargeInteger;
  lpTotalNumberOfFreeBytes: PLargeInteger): Boolean; stdcall;external 'KERNEL32.DLL' name 'GetDiskFreeSpaceExA'

var
  GProcessToHWNDList: TObjectList = nil;

function EnumerateWindowsProc(hwnd: HWND; lParam: LPARAM): BOOL; stdcall;
var
  proc: TProcessToHWND;
begin
  if Assigned(GProcessToHWNDList) then
  begin
    proc := TProcessToHWND.Create;
    proc.HWND := hwnd;
    GetWindowThreadProcessID(hwnd, proc.ProcessID);
    GProcessToHWNDList.Add(proc);
    Result := True;
  end
  else
    Result := False; // stop enumeration
end;

{ TWindows }

class function TWindows.ExeIsRunning(ExeName: string): Boolean;
var
  processList: TProcessList;
  i: Integer;
begin
  Result := False;

  processList := GetProcessList;
  try
    for i := 0 to processList.Count - 1 do
    begin
      if (UpperCase(ExeName) = UpperCase(processList[i].Name)) or
          (UpperCase(ExeName) = UpperCase(ExtractFileName(processList[i].Name))) then
      begin
        Result := True;
        Break;
      end;
    end;
  finally
    processList.Free;
  end;
end;

class function TWindows.GetHWNDFromProcessID(
  ProcessID: Cardinal; BuildList: Boolean): THandle;
var
  i: Integer;
begin
  Result := 0;

  if BuildList or (not Assigned(GProcessToHWNDList)) then
  begin
    GProcessToHWNDList.Free;
    GProcessToHWNDList := TObjectList.Create;
    EnumWindows(@EnumerateWindowsProc, 0);
  end;

  for i := 0 to GProcessToHWNDList.Count - 1 do
  begin
    if TProcessToHWND(GProcessToHWNDList[i]).ProcessID = ProcessID then
    begin
      Result := TProcessToHWND(GProcessToHWNDList[i]).HWND;
      Break;
    end;
  end;
end;


class function TWindows.GetProcessList: TProcessList;
var
  handle: THandle;
  pe: TProcessEntry32;
  process: TProcess;
begin
  Result := TProcessList.Create;

  handle := CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
  pe.dwSize := Sizeof(pe);
  if Process32First(handle, pe) then
  begin
    while True do
    begin
      process := TProcess.Create;
      process.Name := pe.szExeFile;
      process.ID := pe.th32ProcessID;
      Result.Add(process);
      if not Process32Next(handle, pe) then
        Break;
    end;
  end;
  CloseHandle(handle);
end;

function EnumWindowsProc(Ahwnd : HWND;      // handle to parent window
  ALParam : Integer) : BOOL;stdcall;
var
  List : TWindowList;
  Wnd : TWindow;
begin
  Result := True;
  List := TWindowList(ALParam);
  Wnd := TWindow.Create;
  List.Add(Wnd);
  Wnd.FHandle := Ahwnd;
end;


class procedure TWindows.KillProcess(ProcessName: string);
var
  handle: THandle;
  pe: TProcessEntry32;
begin
  // Warning: will kill all process with ProcessName
  // NB won't work on NT 4 as Tool Help API is not supported on NT

  handle := CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
  try
    pe.dwSize := Sizeof(pe);

    if Process32First(handle, pe) then
    begin
      while True do begin
        if (UpperCase(ExtractFileName(pe.szExeFile)) = UpperCase(ExtractFileName(ProcessName))) or
           (UpperCase(pe.szExeFile) = UpperCase(ProcessName)) then
        begin
          if not TerminateProcess(OpenProcess(PROCESS_TERMINATE, False,
                                    pe.th32ProcessID), 0) then
          begin
            raise Exception.Create('Unable to stop process ' + ProcessName + ': Error Code ' + IntToStr(GetLastError));
          end;
        end;
        if not Process32Next(handle, pe) then
          Break;
      end;
    end;
  finally
    CloseHandle(handle);
  end;
end;

class function TWindows.ProcessIsRunning(PID: Cardinal): Boolean;
var
  processList: TProcessList;
  i: Integer;
begin
  Result := False;

  processList := GetProcessList;
  try
    for i := 0 to processList.Count - 1 do
    begin
      if processList[i].ID = PID then
      begin
        Result := True;
        Break;
      end;
    end;
  finally
    processList.Free;
  end;
end;

class procedure TWindows.StopProcess(ProcessName: string);
var
  processList: TProcessList;
  i: Integer;
  hwnd: THandle;
begin
  // Warning: will attempt to stop all process with ProcessName
  if not Assigned(GProcessToHWNDList) then
    GProcessToHWNDList := TObjectList.Create
  else
    GProcessToHWNDList.Clear;

  // get list of all current processes
  processList := GetProcessList;
  // enumerate windows only once to determine the window handle for the processes
  if EnumWindows(@EnumerateWindowsProc, 0) then
  begin
    for i := 0 to processList.Count - 1 do
    begin
      if UpperCase(ExtractFileName(processList[i].Name)) = UpperCase(ExtractFileName(ProcessName)) then
      begin
        hwnd := GetHWNDFromProcessID(processList[i].ID, False);
        SendMessage(hwnd, WM_CLOSE, 0, 0);
      end;
    end;
  end;
end;


{ TProcessList }

function TProcessList.Add(AProcess: TProcess): Integer;
begin
  Result := inherited Add(AProcess);
end;

function TProcessList.GetProcess(AIndex: Integer): TProcess;
begin
  Result := TProcess(Items[AIndex]);
end;

{ TWindowList }

function TWindowList.Add(AWindow: TWindow): Integer;
begin
  Result := inherited Add(AWindow);
end;

function TWindowList.GetWindow(AIndex: Integer): TWindow;
begin
  Result := TWindow(Items[AIndex]);
end;

{ TWindow }

function TWindow.GetProcessHandle: THandle;
begin
  if FProcessHandle = 0 then
    FProcessHandle := OpenProcess(Windows.SYNCHRONIZE or Windows.PROCESS_TERMINATE,
     True, FProcessID);
  Result := FProcessHandle;
end;

function TWindow.GetProcessID: Cardinal;
var
  Pid : Cardinal;
begin
  if FProcessID = 0 then
  begin
    Pid := 1;
    GetWindowThreadProcessId(Handle, Pid);
    FProcessID := Pid;
  end;
  Result := FProcessID;
end;


function TWindow.GetProcessName: string;
var
  Buffer : packed array [1..1024] of char;
  len : LongWord;
begin
  FillChar(Buffer, SizeOf(Buffer), 0);
  if FProcessName = '' then
  begin
    len := GetWindowModuleFileName(Handle, @Buffer[1], 1023);
    FProcessName := Copy(Buffer, 1, Len);
  end;
  Result := FProcessName;
end;

end.