SharpSvn SvnClient.GetLog抛出AccessViolationException

Question

我的应用程序崩溃了，出现了以下未处理的异常：

System.AccessViolationException was unhandled
  HResult=-2147467261
  Message=Attempted to read or write protected memory. This is often an indication that other memory is corrupt.
  Source=SharpSvn
  StackTrace:
       at apr_pool_destroy(apr_pool_t* )
       at SharpSvn.Implementation.AprPool.Destroy()
       at SharpSvn.Implementation.AprPool.Dispose(Boolean )
       at SharpSvn.Implementation.AprPool.Dispose()
       at SharpSvn.SvnClient.InternalLog(ICollection`1 targets, Uri logRoot, SvnRevision altPegRev, SvnLogArgs args, EventHandler`1 logHandler)
       at SharpSvn.SvnClient.Log(Uri target, SvnLogArgs args, EventHandler`1 logHandler)
       at SharpSvn.SvnClient.GetLog(Uri target, SvnLogArgs args, Collection`1& logItems)
       at SourceLog.Plugin.Subversion.SubversionPlugin.CheckForNewLogEntries(Object state)
       at System.Threading.TimerQueueTimer.CallCallbackInContext(Object state)
       at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
       at System.Threading.TimerQueueTimer.CallCallback()
       at System.Threading.TimerQueueTimer.Fire()
       at System.Threading.TimerQueue.FireQueuedTimerCompletion(Object state)
       at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem()
       at System.Threading.ThreadPoolWorkQueue.Dispatch()
       at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback()
  InnerException: 

对SharpSvn.SvnClient.GetLog的调用在这里：https://github.com/tomhunter-gh/SourceLog/blob/2fa0632665550c18c9cd23500610704e3eaa35a2/SourceLog.Plugin.Subversion/SubversionPlugin.cs#L39

Answer 1

看起来这是由于多个计时器回调实例同时调用GetLog，并且该方法(通常是SharpSvn？)不是线程安全的。我添加了一个静态锁对象，以确保一次只有一个线程调用GetLog。