Refactoring

2021-10-22 21:05:37 +02:00
commit ca9de13c9e
43 changed files with 5145 additions and 0 deletions
--- a/AMWD.Common/Extensions/ReaderWriterLockSlimExtensions.cs
+++ b/AMWD.Common/Extensions/ReaderWriterLockSlimExtensions.cs
@@ -0,0 +1,84 @@
+namespace System.Threading
+{
+	/// <summary>
+	/// Provides extension methods for the <see cref="ReaderWriterLockSlim"/>.
+	/// </summary>
+	public static class ReaderWriterLockSlimExtensions
+	{
+		/// <summary>
+		/// Acquires a read lock on a lock object that can be released with an
+		/// <see cref="IDisposable"/> instance.
+		/// </summary>
+		/// <param name="rwLock">The lock object.</param>
+		/// <param name="timeoutMilliseconds">The number of milliseconds to wait, or -1
+		///   (<see cref="Timeout.Infinite"/>) to wait indefinitely.</param>
+		/// <returns>An <see cref="IDisposable"/> instance to release the lock.</returns>
+		public static IDisposable GetReadLock(this ReaderWriterLockSlim rwLock, int timeoutMilliseconds = -1)
+		{
+			if (!rwLock.TryEnterReadLock(timeoutMilliseconds))
+				throw new TimeoutException("The read lock could not be acquired.");
+
+			return new RWLockDisposable(rwLock, 1);
+		}
+
+		/// <summary>
+		/// Acquires a upgradeable read lock on a lock object that can be released with an
+		/// <see cref="IDisposable"/> instance. The lock can be upgraded to a write lock temporarily
+		/// with <see cref="GetWriteLock"/> or until the lock is released with
+		/// <see cref="ReaderWriterLockSlim.EnterWriteLock"/> alone.
+		/// </summary>
+		/// <param name="rwLock">The lock object.</param>
+		/// <param name="timeoutMilliseconds">The number of milliseconds to wait, or -1
+		///   (<see cref="Timeout.Infinite"/>) to wait indefinitely.</param>
+		/// <returns>An <see cref="IDisposable"/> instance to release the lock. If the lock was
+		///   upgraded to a write lock, that will be released as well.</returns>
+		public static IDisposable GetUpgradeableReadLock(this ReaderWriterLockSlim rwLock, int timeoutMilliseconds = -1)
+		{
+			if (!rwLock.TryEnterUpgradeableReadLock(timeoutMilliseconds))
+				throw new TimeoutException("The upgradeable read lock could not be acquired.");
+
+			return new RWLockDisposable(rwLock, 2);
+		}
+
+		/// <summary>
+		/// Acquires a write lock on a lock object that can be released with an
+		/// <see cref="IDisposable"/> instance.
+		/// </summary>
+		/// <param name="rwLock">The lock object.</param>
+		/// <param name="timeoutMilliseconds">The number of milliseconds to wait, or -1
+		///   (<see cref="Timeout.Infinite"/>) to wait indefinitely.</param>
+		/// <returns>An <see cref="IDisposable"/> instance to release the lock.</returns>
+		public static IDisposable GetWriteLock(this ReaderWriterLockSlim rwLock, int timeoutMilliseconds = -1)
+		{
+			if (!rwLock.TryEnterWriteLock(timeoutMilliseconds))
+				throw new TimeoutException("The write lock could not be acquired.");
+
+			return new RWLockDisposable(rwLock, 3);
+		}
+
+		private struct RWLockDisposable : IDisposable
+		{
+			private readonly ReaderWriterLockSlim rwLock;
+			private int lockMode;
+
+			public RWLockDisposable(ReaderWriterLockSlim rwLock, int lockMode)
+			{
+				this.rwLock = rwLock;
+				this.lockMode = lockMode;
+			}
+
+			public void Dispose()
+			{
+				if (lockMode == 1)
+					rwLock.ExitReadLock();
+				if (lockMode == 2 && rwLock.IsWriteLockHeld)   // Upgraded with EnterWriteLock alone
+					rwLock.ExitWriteLock();
+				if (lockMode == 2)
+					rwLock.ExitUpgradeableReadLock();
+				if (lockMode == 3)
+					rwLock.ExitWriteLock();
+				lockMode = 0;
+			}
+		}
+	}
+}