Componentes.Terceros.jvcl/official/3.32/run/JvgSingleInstance.pas

165 lines
4.1 KiB
ObjectPascal

{-----------------------------------------------------------------------------
The contents of this file are subject to the Mozilla Public License
Version 1.1 (the "License"); you may not use this file except in compliance
with the License. You may obtain a copy of the License at
http://www.mozilla.org/MPL/MPL-1.1.html
Software distributed under the License is distributed on an "AS IS" basis,
WITHOUT WARRANTY OF ANY KIND, either expressed or implied. See the License for
the specific language governing rights and limitations under the License.
The Original Code is: JvgSingleInstance.PAS, released on 2003-01-15.
The Initial Developer of the Original Code is Andrey V. Chudin, [chudin att yandex dott ru]
Portions created by Andrey V. Chudin are Copyright (C) 2003 Andrey V. Chudin.
All Rights Reserved.
Contributor(s):
Michael Beck [mbeck att bigfoot dott com].
Burov Dmitry, translation of russian text.
You may retrieve the latest version of this file at the Project JEDI's JVCL home page,
located at http://jvcl.sourceforge.net
Known Issues:
-----------------------------------------------------------------------------}
// $Id: JvgSingleInstance.pas 10612 2006-05-19 19:04:09Z jfudickar $
unit JvgSingleInstance;
{$I jvcl.inc}
interface
uses
{$IFDEF USEJVCL}
{$IFDEF UNITVERSIONING}
JclUnitVersioning,
{$ENDIF UNITVERSIONING}
Windows, Classes, SyncObjs, SysUtils, Forms,
JvComponentBase;
{$ELSE}
Windows, Classes, SyncObjs, SysUtils, Forms;
{$ENDIF USEJVCL}
type
{$IFDEF USEJVCL}
TJvgSingleInstance = class(TJvComponent)
{$ELSE}
TJvgSingleInstance = class(TComponent)
{$ENDIF USEJVCL}
private
FCheckEvent: TEvent;
public
constructor Create(AOwner: TComponent); override;
destructor Destroy; override;
end;
{$IFDEF USEJVCL}
{$IFDEF UNITVERSIONING}
const
UnitVersioning: TUnitVersionInfo = (
RCSfile: '$URL: https://jvcl.svn.sourceforge.net/svnroot/jvcl/tags/JVCL3_32/run/JvgSingleInstance.pas $';
Revision: '$Revision: 10612 $';
Date: '$Date: 2006-05-19 21:04:09 +0200 (ven., 19 mai 2006) $';
LogPath: 'JVCL\run'
);
{$ENDIF UNITVERSIONING}
{$ENDIF USEJVCL}
implementation
{$IFDEF USEJVCL}
uses
JvResources, JvConsts;
{$ENDIF USEJVCL}
{$IFNDEF USEJVCL}
resourcestring
RsOneInstanceOfThisProgramIsAlreadyRu = 'One instance of this program is already running. A second instance launch is not allowed.';
RsSecondInstanceLaunchOfs = 'Second instance launch of %s';
{$ENDIF !USEJVCL}
{ semaphore
var
hs: THandle;
begin
hs := CreateSemaphore(nil, 0, 2, 'MyProgSemaphore');
if GetLastError = ERROR_ALREADY_EXISTS then
Halt;
Application.Initialize;
Application.CreateForm(TForm1, Form1);
Application.Run;
ReleaseSemaphore(hs, 2, 0);
end.
}
{ mutex
const
SAppMutex = 'SomeName';
var
Mtx: THandle;
Wait: Longint;
begin
Application.Initialize;
Mtx := CreateMutex(nil, True, PChar(SAppMutex));
try
Wait := WaitForSingleObject(Mtx, 0);
if (Wait <> WAIT_TIMEOUT) then
begin
OpenMutex(SYNCHRONIZE, False, PChar(SAppMutex));
try
Application.CreateForm(TfrmMain, frmMain);
Application.Run;
finally
ReleaseMutex(Mtx);
end;
end
else
Exit;
finally
CloseHandle(Mtx);
end;
end.
}
constructor TJvgSingleInstance.Create(AOwner: TComponent);
var
S1, S2: string;
begin
inherited Create(AOwner);
if csDesigning in ComponentState then
Exit;
FCheckEvent := TEvent.Create(nil, False, True, ParamStr(0));
if FCheckEvent.WaitFor(10) <> wrSignaled then
begin
S1 := RsOneInstanceOfThisProgramIsAlreadyRu;
S2 := Format(RsSecondInstanceLaunchOfs, [ExtractFileName(ParamStr(0))]);
Application.MessageBox(PChar(S1), PChar(S2), MB_ICONSTOP or MB_OK);
Halt;
end;
end;
destructor TJvgSingleInstance.Destroy;
begin
FCheckEvent.Free;
inherited Destroy;
end;
{$IFDEF USEJVCL}
{$IFDEF UNITVERSIONING}
initialization
RegisterUnitVersion(HInstance, UnitVersioning);
finalization
UnregisterUnitVersion(HInstance);
{$ENDIF UNITVERSIONING}
{$ENDIF USEJVCL}
end.