mfgames-cil/mfgames-locking-cil
Archived
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Activity

feat: removing two proposed features that do not fit the pattern

Browse source
This commit is contained in:
Dylan R. E. Moonfire 2021-01-21 18:15:05 -06:00
parent 678bfc8564
commit a161673e36
2 changed files with 0 additions and 119 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

105
src/MfGames.Locking/TryGetCreate.cs
View file

@ -1,105 +0,0 @@
using System;
using System.Threading;
namespace MfGames.Locking
{
/// <summary>
/// Implements the basic pattern for getting an item from a cache using
/// the ReaderWriterLockSlim class. This attempts to get it using a read-only
/// lock. If that fails, it gets an upgradable lock, tries again, and if it
/// still can't find it, upgrades the lock to a write lock to create it.
/// </summary>
public static class TryGetCreate
{
/// <summary>
/// Invokes the try/get/create pattern used a condition to test for it
/// and a constructor function.
/// </summary>
/// <param name="readerWriterLockSlim">The reader writer lock slim.</param>
/// <param name="conditionHandler">The condition handler.</param>
/// <param name="createHandler">The create handler.</param>
public static void Invoke(
ReaderWriterLockSlim readerWriterLockSlim,
Func<bool> conditionHandler,
Action createHandler)
{
using (new ReadLock(readerWriterLockSlim))
{
// Verify that the condition for creating it is false.
if (!conditionHandler())
{
return;
}
}
// We failed to get the lock using the read-only. We create an upgradable lock
// and try again since it may have been created with a race condition when the
// last lock was released and this one was acquired.
using (new UpgradableLock(readerWriterLockSlim))
{
// Verify that the condition for creating it is false.
if (!conditionHandler())
{
return;
}
// We failed to get it in the lock. Upgrade the lock to a write and create it.
using (new WriteLock(readerWriterLockSlim))
{
createHandler();
}
}
}
/// <summary>
/// Invokes the try/get/create pattern using a tryget retrieval and a
/// creator handler.
/// </summary>
/// <typeparam name="TInput">The type of the input.</typeparam>
/// <typeparam name="TOutput">The type of the output.</typeparam>
/// <param name="readerWriterLockSlim">The reader writer lock slim.</param>
/// <param name="input">The input.</param>
/// <param name="tryGetHandler">The try get handler.</param>
/// <param name="createHandler">The create handler.</param>
/// <returns>The requested output object.</returns>
public static TOutput Invoke<TInput, TOutput>(
ReaderWriterLockSlim readerWriterLockSlim,
TInput input,
TryGetHandler<TInput, TOutput> tryGetHandler,
Func<TInput, TOutput> createHandler)
{
// First attempt to get the item using a read-only lock.
TOutput output;
using (new ReadLock(readerWriterLockSlim))
{
// Try to get the item using the try/get handler.
if (tryGetHandler(input, out output))
{
// We successful got the item in the read-only cache, so just return it.
return output;
}
}
// We failed to get the lock using the read-only. We create an upgradable lock
// and try again since it may have been created with a race condition when the
// last lock was released and this one was acquired.
using (new UpgradableLock(readerWriterLockSlim))
{
// Try to get the item using the try/get handler.
if (tryGetHandler(input, out output))
{
// We successful got the item in this lock, so return it without
// upgrading the lock.
return output;
}
// We failed to get it in the lock. Upgrade the lock to a write and create it.
using (new WriteLock(readerWriterLockSlim))
{
return createHandler(input);
}
}
}
}
}

14
src/MfGames.Locking/TryGetHandler.cs
View file

@ -1,14 +0,0 @@
namespace MfGames.Locking
{
/// <summary>
/// Defines the common try/get handler to retrieve an item of a given type.
/// </summary>
/// <typeparam name="TInput">The type of the input or lookup key.</typeparam>
/// <typeparam name="TOutput">The type of the output.</typeparam>
/// <param name="input">The input value to search for.</param>
/// <param name="output">The resulting output value.</param>
/// <returns>True if the attempt was successful, otherwise false.</returns>
public delegate bool TryGetHandler<in TInput, TOutput>(
TInput input,
out TOutput output);
}