vncinsthandler.cpp

teamviewer source code vc++

//  Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved.
//
//  This file is part of TeamViewer.
//
//  TeamViewer is free software; you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation; either version 2 of the License, or
//  (at your option) any later version.
//
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program; if not, write to the Free Software
//  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
//  USA.
//
//  If the source code for TeamViewer is not available from the place 
//  whence you received this file, check http://www.teamviewer.com
//  for information on obtaining it.


// vncInstHandler.cpp

// Implementation of the class used to ensure that only
// one instance is running

#include "stdhdrs.h"
#include "vncInstHandler.h"
#include "vncService.h"

// Name of the mutex

const char mutexname [] = "TeamViewer_Win32_Instance_Mutex";
const char TV3mutexname [] = "TeamViewer3_Win32_Instance_Mutex";

// The class methods
vncInstHandler::vncInstHandler()
{
	mutex=NULL;
}
BOOL
vncInstHandler::TeamViewer3()
{
	if(!vncService::IsWinNT())
		return TRUE;
	::SetLastError(0);
	HANDLE TV3Mutex;
	TV3Mutex = OpenMutex(NULL, FALSE, TV3mutexname);
	int x = ::GetLastError();
	if ( x== ERROR_FILE_NOT_FOUND)
		return TRUE;
	
	if (TV3Mutex)
	{
		ReleaseMutex(TV3Mutex);
		CloseHandle(TV3Mutex);
		TV3Mutex = NULL;
	}

	return FALSE;
}

vncInstHandler::~vncInstHandler()
{
	if (mutex)
		ReleaseMutex(mutex);
}

BOOL
vncInstHandler::Init()
{
	::SetLastError(0);
	// Create the named mutex
	mutex = CreateMutex(NULL, TRUE, mutexname);
	if (mutex == NULL)
		return FALSE;

	// Check that the mutex didn't already exist
	if (GetLastError() == ERROR_ALREADY_EXISTS)
		return FALSE;

	return TRUE;
}

void vncInstHandler::RemoveMutex()
{
	if(mutex)
	{
		if (!ReleaseMutex(mutex))
			DWORD err = ::GetLastError();
		else
			//ReleaseHandle(mutex);
			CloseHandle(mutex);
			//mutex = NULL;

	}

}