// Note: configuration based on stackoverflow answer: http://stackoverflow.com/questions/229565/what-is-a-good-pattern-for-using-a-global-mutex-in-c
        public BankAccountMutex(double money)
        {
            // get application GUID as defined in AssemblyInfo.cs
            string appGuid = ((GuidAttribute)Assembly.GetExecutingAssembly().GetCustomAttributes(typeof(GuidAttribute), false).GetValue(0)).Value.ToString();

            // unique id for global mutex - Global prefix means it is global to the machine
            string mutexId = string.Format("Global\\{{{0}}}", appGuid);

            // Need a place to store a return value in Mutex() constructor call
            bool createdNew;

            // set up security for multi-user usage
            // work also on localized systems (don't use just "Everyone")
            var allowEveryoneRule = new MutexAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), MutexRights.FullControl, AccessControlType.Allow);
            var securitySettings = new MutexSecurity();
            securitySettings.AddAccessRule(allowEveryoneRule);

            mutex = new Mutex(false, mutexId, out createdNew, securitySettings);

            LogConsole("Setting initial amount of money: " + money);

            if (money < 0)
            {
                LogConsole("The entered money quantity cannot be negative. Money: " + money);
                throw new ArgumentException(GetMessageWithTreadId("The entered money quantity cannot be negative. Money: " + money));
            }

            this.bankMoney = money;
        }

        public unsafe Mutex(bool initiallyOwned, String name, out bool createdNew, MutexSecurity mutexSecurity)
        {
            if(null != name && System.IO.Path.MAX_PATH < name.Length)
            { 
                throw new ArgumentException(Environment.GetResourceString("Argument_WaitHandleNameTooLong",name));
            } 
            Contract.EndContractBlock(); 
            Win32Native.SECURITY_ATTRIBUTES secAttrs = null;
#if !FEATURE_PAL && FEATURE_MACL 
            // For ACL's, get the security descriptor from the MutexSecurity.
            if (mutexSecurity != null) {

                secAttrs = new Win32Native.SECURITY_ATTRIBUTES(); 
                secAttrs.nLength = (int)Marshal.SizeOf(secAttrs);
 
                byte[] sd = mutexSecurity.GetSecurityDescriptorBinaryForm(); 
                byte* pSecDescriptor = stackalloc byte[sd.Length];
                Buffer.memcpy(sd, 0, pSecDescriptor, 0, sd.Length); 
                secAttrs.pSecurityDescriptor = pSecDescriptor;
            }
#endif
 

            RuntimeHelpers.CleanupCode cleanupCode = new RuntimeHelpers.CleanupCode(MutexCleanupCode); 
            MutexCleanupInfo cleanupInfo = new MutexCleanupInfo(null, false); 
            MutexTryCodeHelper tryCodeHelper = new MutexTryCodeHelper(initiallyOwned, cleanupInfo, name, secAttrs, this);
            RuntimeHelpers.TryCode tryCode = new RuntimeHelpers.TryCode(tryCodeHelper.MutexTryCode); 
            RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(
                tryCode,
                cleanupCode,
                cleanupInfo); 
                createdNew = tryCodeHelper.m_newMutex;
 
        } 

        public unsafe Mutex(bool initiallyOwned, String name, out bool createdNew, MutexSecurity mutexSecurity)
        {
            if (name == string.Empty)
            {
                // Empty name is treated as an unnamed mutex. Set to null, and we will check for null from now on.
                name = null;
            }
#if !PLATFORM_UNIX
            if (name != null && System.IO.Path.MaxPath < name.Length)
            {
                throw new ArgumentException(Environment.GetResourceString("Argument_WaitHandleNameTooLong", Path.MaxPath), "name");
            }
#endif
            Contract.EndContractBlock();
            Win32Native.SECURITY_ATTRIBUTES secAttrs = null;
#if FEATURE_MACL
            // For ACL's, get the security descriptor from the MutexSecurity.
            if (mutexSecurity != null) {

                secAttrs = new Win32Native.SECURITY_ATTRIBUTES();
                secAttrs.nLength = (int)Marshal.SizeOf(secAttrs);

                byte[] sd = mutexSecurity.GetSecurityDescriptorBinaryForm();
                byte* pSecDescriptor = stackalloc byte[sd.Length];
                Buffer.Memcpy(pSecDescriptor, 0, sd, 0, sd.Length);
                secAttrs.pSecurityDescriptor = pSecDescriptor;
            }
#endif

            CreateMutexWithGuaranteedCleanup(initiallyOwned, name, out createdNew, secAttrs);
        }

        public InterProcessMutexLock(String mutexName)
        {
            try
            {
                _mutexName = mutexName;

                try
                {
                    _currentMutex = Mutex.OpenExisting(_mutexName);
                }
                catch (WaitHandleCannotBeOpenedException)
                {
                    // grant everyone access to the mutex
                    var security = new MutexSecurity();
                    var everyoneIdentity = new SecurityIdentifier(WellKnownSidType.WorldSid, null);
                    var rule = new MutexAccessRule(everyoneIdentity, MutexRights.FullControl, AccessControlType.Allow);
                    security.AddAccessRule(rule);

                    // make sure to not initially own it, because if you do it also acquires the lock
                    // we want to explicitly attempt to acquire the lock ourselves so we know how many times
                    // this object acquired and released the lock
                    _currentMutex = new Mutex(false, mutexName, out _created, security);
                }

                AquireMutex();
            }
            catch(Exception ex)
            {
                var exceptionString = String.Format("Exception in InterProcessMutexLock, mutex name {0}", mutexName);
                Log.Error(this, exceptionString, ex);
                throw ExceptionUtil.Rethrow(ex, exceptionString);
            }
        }

 public static bool ObtainMutex(string settingsFolder)
 {
     SecurityIdentifier sid = new SecurityIdentifier(WellKnownSidType.WorldSid, null);
     MutexSecurity security = new MutexSecurity();
     bool useDefaultSecurity = false;
     bool createdNew;
     try {
         security.AddAccessRule(new MutexAccessRule(sid, MutexRights.FullControl, AccessControlType.Allow));
         security.AddAccessRule(new MutexAccessRule(sid, MutexRights.ChangePermissions, AccessControlType.Deny));
         security.AddAccessRule(new MutexAccessRule(sid, MutexRights.Delete, AccessControlType.Deny));
     }
     catch (Exception ex) {
         if (ex is ArgumentOutOfRangeException || ex is NotImplementedException) {
             // Workaround for Mono
             useDefaultSecurity = true;
         }
         else {
             throw;
         }
     }
     string name = @"Global\ChanThreadWatch_" + General.Calculate64BitMD5(Encoding.UTF8.GetBytes(
         settingsFolder.ToUpperInvariant())).ToString("X16");
     Mutex mutex = !useDefaultSecurity ?
         new Mutex(false, name, out createdNew, security) :
         new Mutex(false, name);
     try {
         if (!mutex.WaitOne(0, false)) {
             return false;
         }
     }
     catch (AbandonedMutexException) { }
     ReleaseMutex();
     _mutex = mutex;
     return true;
 }

        public static Mutex GrabMutex(string name)
        {
            var mutexName = "kalixLuceneSegmentMutex_" + name;
            try
            {
                return Mutex.OpenExisting(mutexName);
            }
            catch (WaitHandleCannotBeOpenedException)
            {
                var worldSid = new SecurityIdentifier(WellKnownSidType.WorldSid, null);
                var security = new MutexSecurity();
                var rule = new MutexAccessRule(worldSid, MutexRights.FullControl, AccessControlType.Allow);
                security.AddAccessRule(rule);
                var mutexIsNew = false;
                return new Mutex(false, mutexName, out mutexIsNew, security);
            }
            catch (UnauthorizedAccessException)
            {
                var m = Mutex.OpenExisting(mutexName, MutexRights.ReadPermissions | MutexRights.ChangePermissions);
                var security = m.GetAccessControl();
                var user = Environment.UserDomainName + "\\" + Environment.UserName;
                var rule = new MutexAccessRule(user, MutexRights.Synchronize | MutexRights.Modify, AccessControlType.Allow);
                security.AddAccessRule(rule);
                m.SetAccessControl(security);

                return Mutex.OpenExisting(mutexName);
            }
        }

        public static void SetAccessControl (this Mutex mutex, MutexSecurity mutexSecurity)
        {
            if (mutex == null)
                throw new ArgumentNullException (nameof (mutex));

            mutex.SetAccessControl (mutexSecurity);
        }

        protected override void OnStartup(StartupEventArgs e)
        {
            // store mutex result
            bool createdNew;

            // allow multiple users to run it, but only one per user
            var allowEveryoneRule = new MutexAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), MutexRights.FullControl, AccessControlType.Allow);
            var securitySettings = new MutexSecurity();
            securitySettings.AddAccessRule(allowEveryoneRule);

            // create mutex
            _instanceMutex = new Mutex(true, @"Global\MercurialForge_Mastery", out createdNew, securitySettings);

            // check if conflict
            if (!createdNew)
            {
                MessageBox.Show("Instance of Mastery is already running");
                _instanceMutex = null;
                Application.Current.Shutdown();
                return;
            }

            base.OnStartup(e);
            MainWindow window = new MainWindow();
            MainWindowViewModel viewModel = new MainWindowViewModel(window);
            window.DataContext = viewModel;
            window.Show();
        }

        /// <summary>
        /// Tries to aquire a mutex with the name <see cref="MutexName"/>. Call this at the end of your constructors.
        /// </summary>
        /// <exception cref="UnauthorizedAccessException">Another process is already holding the mutex.</exception>
        protected void AquireMutex()
        {
            if (MachineWide)
            {
                var mutexSecurity = new MutexSecurity();
                mutexSecurity.AddAccessRule(new MutexAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), MutexRights.FullControl, AccessControlType.Allow));
                bool createdNew;
                _mutex = new Mutex(false, @"Global\" + MutexName, out createdNew, mutexSecurity);
            }
            _mutex = new Mutex(false, MutexName);

            try
            {
                switch (WaitHandle.WaitAny(new[] {_mutex, Handler.CancellationToken.WaitHandle},
                    millisecondsTimeout: (Handler.Verbosity == Verbosity.Batch) ? 30000 : 1000, exitContext: false))
                {
                    case 0:
                        return;
                    case 1:
                        throw new OperationCanceledException();
                    default:
                    case WaitHandle.WaitTimeout:
                        throw new UnauthorizedAccessException("Another process is already holding the mutex " + MutexName + ".");
                }
            }
            catch (AbandonedMutexException ex)
            {
                // Abandoned mutexes also get owned, but indicate something may have gone wrong elsewhere
                Log.Warn(ex.Message);
            }
        }

        public UIMutex(string mutexName)
        {
            pGlobalMutexName = mutexName;

            // Create a string representing the current user.
            string userName = Environment.UserDomainName + "\\" + Environment.UserName;

            // Create a security object that grants no access.
            MutexSecurity mutexSecurity = new MutexSecurity();

            // Add a rule that grants the current user the right
            // to enter or release the mutex.
            MutexAccessRule mutexAccessRule = new MutexAccessRule(userName, MutexRights.FullControl, AccessControlType.Allow);
            mutexSecurity.AddAccessRule(mutexAccessRule);

            bool createdNew = false;
            pMutex = new Mutex(false, pGlobalMutexName, out createdNew, mutexSecurity);

            if (createdNew)
            {
                // loggingSystem.LogVerbose("New Mutex created {0}", pGlobalMutexName);
            }
            else
            {
                //loggingSystem.LogVerbose("Existing Mutex opened {0}", globalMutextName);
            }

        }

        public unsafe Mutex(bool initiallyOwned, String name, out bool createdNew, MutexSecurity mutexSecurity)
        {
            if (name != null)
            {
#if PLATFORM_UNIX
                throw new PlatformNotSupportedException(Environment.GetResourceString("PlatformNotSupported_NamedSynchronizationPrimitives"));
#else
                if (System.IO.Path.MaxPath < name.Length)
                {
                    throw new ArgumentException(Environment.GetResourceString("Argument_WaitHandleNameTooLong", name));
                }
#endif
            }
            Contract.EndContractBlock();
            Win32Native.SECURITY_ATTRIBUTES secAttrs = null;
#if FEATURE_MACL
            // For ACL's, get the security descriptor from the MutexSecurity.
            if (mutexSecurity != null) {

                secAttrs = new Win32Native.SECURITY_ATTRIBUTES();
                secAttrs.nLength = (int)Marshal.SizeOf(secAttrs);

                byte[] sd = mutexSecurity.GetSecurityDescriptorBinaryForm();
                byte* pSecDescriptor = stackalloc byte[sd.Length];
                Buffer.Memcpy(pSecDescriptor, 0, sd, 0, sd.Length);
                secAttrs.pSecurityDescriptor = pSecDescriptor;
            }
#endif

            CreateMutexWithGuaranteedCleanup(initiallyOwned, name, out createdNew, secAttrs);
        }

        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(true);

            string title = "KeyMagic";

            bool beta = Properties.Settings.Default.BetaRelease;

            if (beta) title += " (beta)";

            string mutexName = "\u1000\u1001";

            // http://stackoverflow.com/questions/229565/what-is-a-good-pattern-for-using-a-global-mutex-in-c/229567
            using (var mutex = new Mutex(false, mutexName))
            {
                // edited by Jeremy Wiebe to add example of setting up security for multi-user usage
                // edited by 'Marc' to work also on localized systems (don't use just "Everyone")
                var allowEveryoneRule = new MutexAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), MutexRights.FullControl, AccessControlType.Allow);
                var securitySettings = new MutexSecurity();
                securitySettings.AddAccessRule(allowEveryoneRule);
                mutex.SetAccessControl(securitySettings);

                //edited by acidzombie24
                var hasHandle = false;
                try
                {
                    try
                    {
                        // note, you may want to time out here instead of waiting forever
                        //edited by acidzombie24
                        //mutex.WaitOne(Timeout.Infinite, false);
                        hasHandle = mutex.WaitOne(100, false);
                        if (hasHandle == false) //another instance exist
                        {
                            IntPtr pWnd = NativeMethods.FindWindow(null, title);
                            if (pWnd != IntPtr.Zero)
                            {
                                NativeMethods.ShowWindow(pWnd, 0x05);
                            }
                            return;
                        }
                    }
                    catch (AbandonedMutexException)
                    {
                        // Log the fact the mutex was abandoned in another process, it will still get aquired
                    }

                    frmMain f = new frmMain();
                    Application.Run();
                }
                finally
                {
                    //edit by acidzombie24, added if statemnet
                    if (hasHandle)
                        mutex.ReleaseMutex();
                }
            }
        }

 public unsafe Mutex(bool initiallyOwned, string name, out bool createdNew, MutexSecurity mutexSecurity)
 {
     if ((name != null) && (260 < name.Length))
     {
         throw new ArgumentException(Environment.GetResourceString("Argument_WaitHandleNameTooLong", new object[] { name }));
     }
     Win32Native.SECURITY_ATTRIBUTES secAttrs = null;
     if (mutexSecurity != null)
     {
         secAttrs = new Win32Native.SECURITY_ATTRIBUTES {
             nLength = Marshal.SizeOf(secAttrs)
         };
         byte[] securityDescriptorBinaryForm = mutexSecurity.GetSecurityDescriptorBinaryForm();
         byte* pDest = stackalloc byte[1 * securityDescriptorBinaryForm.Length];
         Buffer.memcpy(securityDescriptorBinaryForm, 0, pDest, 0, securityDescriptorBinaryForm.Length);
         secAttrs.pSecurityDescriptor = pDest;
     }
     SafeWaitHandle mutexHandle = null;
     bool newMutex = false;
     RuntimeHelpers.CleanupCode backoutCode = new RuntimeHelpers.CleanupCode(this.MutexCleanupCode);
     MutexCleanupInfo cleanupInfo = new MutexCleanupInfo(mutexHandle, false);
     RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(delegate (object userData) {
         RuntimeHelpers.PrepareConstrainedRegions();
         try
         {
         }
         finally
         {
             if (initiallyOwned)
             {
                 cleanupInfo.inCriticalRegion = true;
                 Thread.BeginThreadAffinity();
                 Thread.BeginCriticalRegion();
             }
         }
         int errorCode = 0;
         RuntimeHelpers.PrepareConstrainedRegions();
         try
         {
         }
         finally
         {
             errorCode = CreateMutexHandle(initiallyOwned, name, secAttrs, out mutexHandle);
         }
         if (mutexHandle.IsInvalid)
         {
             mutexHandle.SetHandleAsInvalid();
             if (((name != null) && (name.Length != 0)) && (6 == errorCode))
             {
                 throw new WaitHandleCannotBeOpenedException(Environment.GetResourceString("Threading.WaitHandleCannotBeOpenedException_InvalidHandle", new object[] { name }));
             }
             __Error.WinIOError(errorCode, name);
         }
         newMutex = errorCode != 0xb7;
         this.SetHandleInternal(mutexHandle);
         this.hasThreadAffinity = true;
     }, backoutCode, cleanupInfo);
     createdNew = newMutex;
 }

        [System.Security.SecuritySafeCritical]  // auto-generated
        public static void SetAccessControl(this Mutex mutex, MutexSecurity mutexSecurity)
        {
            if (mutexSecurity == null)
                throw new ArgumentNullException("mutexSecurity");
            Contract.EndContractBlock();

            mutexSecurity.Persist(mutex.GetSafeWaitHandle());
        }

 public static Mutex CreateMutexWithFullControlRights(String name, out Boolean createdNew)
 {
     SecurityIdentifier securityIdentifier = new SecurityIdentifier(WellKnownSidType.WorldSid, null);
     MutexSecurity mutexSecurity = new MutexSecurity();
     MutexAccessRule rule = new MutexAccessRule(securityIdentifier, MutexRights.FullControl, AccessControlType.Allow);
     mutexSecurity.AddAccessRule(rule);
     return new Mutex(false, name, out createdNew, mutexSecurity);
 }

 public InterProcessLock(string name, TimeSpan timeout)
 {
     bool created;
     var security = new MutexSecurity();
     security.AddAccessRule(new MutexAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), MutexRights.Synchronize | MutexRights.Modify, AccessControlType.Allow));
     this.Mutex = new Mutex(false, name, out created, security);
     this.IsAcquired = this.Mutex.WaitOne(timeout);
 }

        /// <summary>
        /// Create the mutex instance used to singal that one or more listeners are active.
        /// </summary>
        /// <param name="mutexName">The shared mutex name.</param>
        protected static Mutex CreateMutex(String mutexName)
        {
            var securitySettings = new MutexSecurity();
            var createdNew = false;

            securitySettings.AddAccessRule(new MutexAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), MutexRights.FullControl, AccessControlType.Allow));

            return new Mutex(false, mutexName, out createdNew, securitySettings);
        }

 internal static void EnterMutexWithoutGlobal(string mutexName, ref Mutex mutex)
 {
     bool flag;
     MutexSecurity mutexSecurity = new MutexSecurity();
     SecurityIdentifier identity = new SecurityIdentifier(WellKnownSidType.AuthenticatedUserSid, null);
     mutexSecurity.AddAccessRule(new MutexAccessRule(identity, MutexRights.Synchronize | MutexRights.Modify, AccessControlType.Allow));
     Mutex mutexIn = new Mutex(false, mutexName, out flag, mutexSecurity);
     SafeWaitForMutex(mutexIn, ref mutex);
 }

        private void InitMutex(Guid appGuid)
        {
            var mutexId = string.Format("Global\\{{{0}}}", appGuid);
            _mutex = new Mutex(false, mutexId);

            var allowEveryoneRule = new MutexAccessRule(new SecurityIdentifier(WellKnownSidType.WorldSid, null), MutexRights.FullControl, AccessControlType.Allow);
            var securitySettings = new MutexSecurity();
            securitySettings.AddAccessRule(allowEveryoneRule);
            _mutex.SetAccessControl(securitySettings);
        }

        public static MutexSecurity MutexSecurity()
            {
            SecurityIdentifier user = GetEveryoneSID();
            MutexSecurity result = new MutexSecurity();

            MutexAccessRule rule = new MutexAccessRule(user, MutexRights.Synchronize | MutexRights.Modify | MutexRights.Delete, AccessControlType.Allow);
            result.AddAccessRule(rule);

            return result;
            }