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    <ol> <li>Move the IsCorrupt test and the Monitor.Enter inside the Try </li> <li>Move the corruption set handling out of finally and into the Catch block (this should only execute if an exception has been thrown)</li> <li>Don't release the primary lock until after the corruption flag has been set (leave it in the finaly block)</li> <li>Don't restrict the execption to the calling thread; either rethow it or add it to the coruption dictionary by replacing the bool with the custom execption, and return it with the IsCorrupt Check</li> <li>For Uncorrupt simply remove the item</li> <li>There are some issues with the locking sequencing (see below)</li> </ol> <p>That should cover all the bases</p> <pre><code> public static class Locking { private static readonly Dictionary&lt;object, Exception&gt; CorruptionStateDictionary = new Dictionary&lt;object, Exception&gt;(); private static readonly object CorruptionLock = new object(); public static bool TryLockedAction(object lockObject, Action action, out Exception exception) { var lockTaken = false; exception = null; try { Monitor.Enter(lockObject, ref lockTaken); if (IsCorrupt(lockObject)) { exception = new LockingException("Cannot execute locked action on a corrupt object."); return false; } action.Invoke(); } catch (Exception ex) { var corruptionLockTaken = false; exception = ex; try { Monitor.Enter(CorruptionLock, ref corruptionLockTaken); if (CorruptionStateDictionary.ContainsKey(lockObject)) { CorruptionStateDictionary[lockObject] = ex; } else { CorruptionStateDictionary.Add(lockObject, ex); } } finally { if (corruptionLockTaken) { Monitor.Exit(CorruptionLock); } } } finally { if (lockTaken) { Monitor.Exit(lockObject); } } return exception == null; } public static void Uncorrupt(object corruptLockObject) { var lockTaken = false; try { Monitor.Enter(CorruptionLock, ref lockTaken); if (IsCorrupt(corruptLockObject)) { { CorruptionStateDictionary.Remove(corruptLockObject); } } } finally { if (lockTaken) { Monitor.Exit(CorruptionLock); } } } public static bool IsCorrupt(object lockObject) { Exception ex = null; return IsCorrupt(lockObject, out ex); } public static bool IsCorrupt(object lockObject, out Exception ex) { var lockTaken = false; ex = null; try { Monitor.Enter(CorruptionLock, ref lockTaken); if (CorruptionStateDictionary.ContainsKey(lockObject)) { ex = CorruptionStateDictionary[lockObject]; } return CorruptionStateDictionary.ContainsKey(lockObject); } finally { if (lockTaken) { Monitor.Exit(CorruptionLock); } } } } </code></pre>
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    1. POWhat is wrong with this solution to locking and managing locked exceptions?
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    1. COMoving the Monitor.Enter inside the Try would cause the object to remain locked when an exception is thrown.
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    2. COSee the code sample
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    3. COfrom Eric Lippert: In C# 4.0 we've changed lock so that it now generates code as if it were bool lockWasTaken = false; var temp = obj; try { Monitor.Enter(temp, ref lockWasTaken); { body } } finally { if (lockWasTaken) Monitor.Exit(temp); }
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