diff --git a/Greenshot/Forms/MainForm.cs b/Greenshot/Forms/MainForm.cs index e58af6640..784dd6bbf 100644 --- a/Greenshot/Forms/MainForm.cs +++ b/Greenshot/Forms/MainForm.cs @@ -26,8 +26,6 @@ using System.Diagnostics; using System.Drawing; using System.IO; using System.Reflection; -using System.Security.AccessControl; -using System.Security.Principal; using System.Text; using System.Threading; using System.Windows.Forms; @@ -52,7 +50,7 @@ namespace Greenshot { /// public partial class MainForm : BaseForm { private static ILog LOG; - private static Mutex _applicationMutex; + private static ResourceMutex _applicationMutex; private static CoreConfiguration _conf; public static string LogFileLocation = null; @@ -82,38 +80,9 @@ namespace Greenshot { try { // Fix for Bug 2495900, Multi-user Environment // check whether there's an local instance running already - - try { - // Added Mutex Security, hopefully this prevents the UnauthorizedAccessException more gracefully - // See an example in Bug #3131534 - SecurityIdentifier sid = new SecurityIdentifier(WellKnownSidType.WorldSid, null); - MutexSecurity mutexsecurity = new MutexSecurity(); - mutexsecurity.AddAccessRule(new MutexAccessRule(sid, MutexRights.FullControl, AccessControlType.Allow)); - mutexsecurity.AddAccessRule(new MutexAccessRule(sid, MutexRights.ChangePermissions, AccessControlType.Deny)); - mutexsecurity.AddAccessRule(new MutexAccessRule(sid, MutexRights.Delete, AccessControlType.Deny)); + _applicationMutex = ResourceMutex.Create("F48E86D3-E34C-4DB7-8F8F-9A0EA55F0D08", "Greenshot", false); - bool created; - // 1) Create Mutex - _applicationMutex = new Mutex(false, @"Local\F48E86D3-E34C-4DB7-8F8F-9A0EA55F0D08", out created, mutexsecurity); - // 2) Get the right to it, this returns false if it's already locked - if (!_applicationMutex.WaitOne(0, false)) { - LOG.Debug("Greenshot seems already to be running!"); - isAlreadyRunning = true; - // Clean up - _applicationMutex.Close(); - _applicationMutex = null; - } - } catch (AbandonedMutexException e) { - // Another Greenshot instance didn't cleanup correctly! - // we can ignore the exception, it happend on the "waitone" but still the mutex belongs to us - LOG.Warn("Greenshot didn't cleanup correctly!", e); - } catch (UnauthorizedAccessException e) { - LOG.Warn("Greenshot is most likely already running for a different user in the same session, can't create mutex due to error: ", e); - isAlreadyRunning = true; - } catch (Exception e) { - LOG.Warn("Problem obtaining the Mutex, assuming it was already taken!", e); - isAlreadyRunning = true; - } + isAlreadyRunning = !_applicationMutex.IsLocked; if (args.Length > 0 && LOG.IsDebugEnabled) { StringBuilder argumentString = new StringBuilder(); @@ -316,7 +285,7 @@ namespace Greenshot { // Remove the application mutex if (_applicationMutex != null) { try { - _applicationMutex.ReleaseMutex(); + _applicationMutex.Dispose(); _applicationMutex = null; } catch (Exception ex) { LOG.Error("Error releasing Mutex!", ex); diff --git a/Greenshot/Greenshot.csproj b/Greenshot/Greenshot.csproj index ee50aa76a..eb756b36a 100644 --- a/Greenshot/Greenshot.csproj +++ b/Greenshot/Greenshot.csproj @@ -212,6 +212,7 @@ + diff --git a/Greenshot/Helpers/ResourceMutex.cs b/Greenshot/Helpers/ResourceMutex.cs new file mode 100644 index 000000000..becab8262 --- /dev/null +++ b/Greenshot/Helpers/ResourceMutex.cs @@ -0,0 +1,195 @@ +/* + Dapplo - building blocks for desktop applications + Copyright (C) 2015-2016 Dapplo + + For more information see: http://dapplo.net/ + Dapplo repositories are hosted on GitHub: https://github.com/dapplo + + This file is part of Dapplo.Addons + + Dapplo.Addons 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 3 of the License, or + (at your option) any later version. + + Dapplo.Addons 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 Dapplo.Addons. If not, see . + */ + + +using log4net; +using System; +using System.Security.AccessControl; +using System.Security.Principal; +using System.Threading; + +namespace Greenshot.Helpers +{ + /// + /// This comes from Dapplo.Addons, which was created for Greenshot, this file is copied here as this is the only part we use in 1.2.8 + /// This protects your resources or application from running more than once + /// Simplifies the usage of the Mutex class, as described here: https://msdn.microsoft.com/en-us/library/System.Threading.Mutex.aspx + /// + public class ResourceMutex : IDisposable + { + private static ILog LOG = LogManager.GetLogger(typeof(DestinationHelper)); + private readonly string _mutexId; + private readonly string _resourceName; + private Mutex _applicationMutex; + + /// + /// Test if the Mutex was created and locked. + /// + public bool IsLocked + { + get; + set; + } + + /// + /// Private constructor + /// + /// + /// + private ResourceMutex(string mutexId, string resourceName = null) + { + _mutexId = mutexId; + _resourceName = resourceName ?? "some resource"; + } + + /// + /// Create a ResourceMutex for the specified mutex id and resource-name + /// + /// ID of the mutex, preferably a Guid as string + /// Name of the resource to lock, e.g your application name, usefull for logs + /// true to have a global mutex see: https://msdn.microsoft.com/en-us/library/bwe34f1k.aspx + public static ResourceMutex Create(string mutexId, string resourceName = null, bool global = false) + { + var applicationMutex = new ResourceMutex((global ? @"Global\" : @"Local\") + mutexId, resourceName); + applicationMutex.Lock(); + return applicationMutex; + } + + /// + /// This tries to get the Mutex, which takes care of having multiple instances running + /// + /// true if it worked, false if another instance is already running or something went wrong + public bool Lock() + { + LOG.DebugFormat("{0} is trying to get Mutex {1}", _resourceName, _mutexId); + + IsLocked = true; + // check whether there's an local instance running already, but use local so this works in a multi-user environment + try + { + // Added Mutex Security, hopefully this prevents the UnauthorizedAccessException more gracefully + var sid = new SecurityIdentifier(WellKnownSidType.WorldSid, null); + var mutexsecurity = new MutexSecurity(); + mutexsecurity.AddAccessRule(new MutexAccessRule(sid, MutexRights.FullControl, AccessControlType.Allow)); + mutexsecurity.AddAccessRule(new MutexAccessRule(sid, MutexRights.ChangePermissions, AccessControlType.Deny)); + mutexsecurity.AddAccessRule(new MutexAccessRule(sid, MutexRights.Delete, AccessControlType.Deny)); + + bool createdNew; + // 1) Create Mutex + _applicationMutex = new Mutex(true, _mutexId, out createdNew, mutexsecurity); + // 2) if the mutex wasn't created new get the right to it, this returns false if it's already locked + if (!createdNew && !_applicationMutex.WaitOne(100, false)) + { + LOG.InfoFormat("{0} is already in use, mutex {1} is NOT locked for the caller", _resourceName, _mutexId); + IsLocked = false; + // Clean up + _applicationMutex.Close(); + _applicationMutex = null; + } + else + { + if (createdNew) + { + LOG.InfoFormat("{0} has created & claimed the mutex {1}", _resourceName, _mutexId); + } + else + { + LOG.InfoFormat("{0} has claimed the mutex {1}", _resourceName, _mutexId); + + } + } + } + catch (AbandonedMutexException e) + { + // Another instance didn't cleanup correctly! + // we can ignore the exception, it happend on the "waitone" but still the mutex belongs to us + LOG.WarnFormat("{0} didn't cleanup correctly, but we got the mutex {1}.", _resourceName, _mutexId); + LOG.Warn(e); + } + catch (UnauthorizedAccessException e) + { + LOG.ErrorFormat("{0} is most likely already running for a different user in the same session, can't create/get mutex {1} due to error.", _resourceName, _mutexId); + LOG.Error(e); + IsLocked = false; + } + catch (Exception ex) + { + LOG.ErrorFormat("Problem obtaining the Mutex {1} for {0}, assuming it was already taken!", _resourceName, _mutexId); + LOG.Error(ex); + IsLocked = false; + } + return IsLocked; + } + + #region IDisposable Support + // To detect redundant Dispose calls + private bool _disposedValue = false; + + /// + /// The real disposing code + /// + /// true if dispose is called, false when the finalizer is called + protected virtual void Dispose(bool disposing) + { + if (!_disposedValue) + { + if (_applicationMutex != null) + { + try + { + _applicationMutex.ReleaseMutex(); + _applicationMutex = null; + LOG.InfoFormat("Released Mutex {0} for {1}", _mutexId, _resourceName); + } + catch (Exception ex) + { + LOG.ErrorFormat("Error releasing Mutex {0} for {1}", _mutexId, _resourceName); + LOG.Error(ex); + } + + } + _disposedValue = true; + } + } + + /// + /// Make sure the ApplicationMutex is disposed when the finalizer is called + /// + ~ResourceMutex() + { + // Do not change this code. Put cleanup code in Dispose(bool disposing) above. + Dispose(false); + } + + /// + /// The dispose interface, which calls Dispose(true) to signal that dispose is called. + /// + public void Dispose() + { + // Do not change this code. Put cleanup code in Dispose(bool disposing) above. + Dispose(true); + GC.SuppressFinalize(this); + } + #endregion + } +}