When using https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlock[ReaderWriterLock] and https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlockslim[ReaderWriterLockSlim] for managing read and write locks, you should not release a read lock while holding a write lock and vice versa, otherwise you might have runtime exceptions.
The locks should be always correctly paired so that the shared resource is accessed safely.

This rule raises if:

* you call https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlock.acquirewriterlock[ReaderWriterLock.AcquireWriterLock] or https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlock.upgradetowriterlock[ReaderWriterLock.UpgradeToWriterLock] and then use https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlock.releasereaderlock[ReaderWriterLock.ReleaseReaderLock]
* you call https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlockslim.enterwritelock[ReaderWriterLockSlim.EnterWriteLock] or https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlockslim.tryenterwritelock[ReaderWriterLockSlim.TryEnterWriteLock] and then use https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlockslim.exitreadlock[ReaderWriterLockSlim.ExitReadLock]
* you call https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlock.acquirereaderlock[ReaderWriterLock.AcquireReaderLock] or https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlock.downgradefromwriterlock[ReaderWriterLock.DowngradeFromWriterLock] and then use https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlock.releasewriterlock[ReaderWriterLock.ReleaseWriterLock]
* or you call https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlockslim.enterreadlock[ReaderWriterLockSlim.EnterReadLock], https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlockslim.tryenterreadlock[ReaderWriterLockSlim.TryEnterReadLock], https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlockslim.enterupgradeablereadlock[ReaderWriterLockSlim.EnterUpgradeableReadLock] or https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlockslim.tryenterupgradeablereadlock[ReaderWriterLockSlim.TryEnterUpgradeableReadLock] and then use https://learn.microsoft.com/en-us/dotnet/api/system.threading.readerwriterlockslim.exitwritelock[ReaderWriterLockSlim.ExitWriteLock]


== Why is this an issue?

If you use the `ReaderWriterLockSlim` class, you will get a https://learn.microsoft.com/en-us/dotnet/api/system.threading.lockrecursionexception[LockRecursionException].
In the case of `ReaderWriterLock`, you'll get a runtime exception for trying to release a lock that is not owned by the calling thread.