V10: Fix build warnings in core (#12438)
* Run code cleanup * Start manual cleanup after dotnet format * Finish up manual pass * Fix up missed warnings * Fix after merge * Update src/Umbraco.Core/Cache/ContentTypeCacheRefresher.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Cache/DataTypeCacheRefresher.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Cache/DeepCloneAppCache.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Cache/DomainCacheRefresher.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Cache/FastDictionaryAppCacheBase.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Cache/FastDictionaryAppCacheBase.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Cache/FastDictionaryAppCacheBase.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Cache/FastDictionaryAppCacheBase.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Cache/FastDictionaryAppCacheBase.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Cache/MacroCacheRefresher.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Cache/MediaCacheRefresher.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Cache/MemberCacheRefresher.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Cache/MemberGroupCacheRefresher.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Composing/OrderedCollectionBuilderBase.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Configuration/Models/RequestHandlerSettings.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Composing/SetCollectionBuilderBase.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Composing/WeightedCollectionBuilderBase.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/ContentApps/ContentAppFactoryCollectionBuilder.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Dashboards/DashboardCollectionBuilder.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/ContentTypeRefreshedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/ContentTypeSavedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/ContentTypeSavingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/DictionaryCacheRefresherNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/DataTypeCacheRefresherNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/ContentUnpublishingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/DictionaryItemDeletingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/DictionaryItemSavedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/DictionaryItemSavingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/DomainCacheRefresherNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/LanguageCacheRefresherNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MacroCacheRefresherNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaCacheRefresherNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaEmptiedRecycleBinNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaEmptyingRecycleBinNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaMovedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaMovedToRecycleBinNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaMovedToRecycleBinNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaMovingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaMovingToRecycleBinNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaTreeChangeNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaTreeChangeNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaTypeChangedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaTypeDeletingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaTypeMovedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaTypeMovingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaTypeMovingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MediaTypeRefreshedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberCacheRefresherNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberGroupCacheRefresherNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberGroupDeletingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberGroupSavedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberGroupSavingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberTypeChangedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberTypeDeletedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberTypeDeletingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberTypeMovedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberTypeMovedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberTypeMovingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberTypeMovingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberTypeRefreshedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MemberTypeSavingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/StringExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/UriExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MovedToRecycleBinNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MovedToRecycleBinNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MovingToRecycleBinNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/MovingToRecycleBinNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/PartialViewDeletingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Extensions/UriExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/IO/PhysicalFileSystem.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/IO/PhysicalFileSystem.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/IO/ShadowWrapper.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Logging/DisposableTimer.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Install/InstallSteps/UpgradeStep.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Mapping/MapDefinitionCollectionBuilder.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Media/EmbedProviders/EmbedProvidersCollectionBuilder.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/PartialViewSavedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Models/ContentEditing/ContentVariationDisplay.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/PartialViewSavingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/PublicAccessCacheRefresherNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/PublicAccessEntryDeletedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/PublicAccessEntryDeletingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/PublicAccessEntryDeletingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/PublicAccessEntrySavedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/PublicAccessEntrySavingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/PublicAccessEntrySavingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/RelationTypeCacheRefresherNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/RelationTypeDeletingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/RelationTypeSavedNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/RelationTypeSavingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/StatefulNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/StylesheetDeletingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Notifications/StylesheetSavingNotification.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Models/DeepCloneHelper.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Models/File.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Models/PropertyGroupExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Update src/Umbraco.Core/Models/PropertyGroupExtensions.cs Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> * Fix based on review * Fix after merge Signed-off-by: Zeegaan <nge@umbraco.dk> Co-authored-by: Nikolaj Geisle <niko737@edu.ucl.dk> Co-authored-by: Mole <nikolajlauridsen@protonmail.ch> Co-authored-by: Zeegaan <nge@umbraco.dk>
This commit is contained in:
Nikolaj Geisle
@@ -1,194 +1,181 @@
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using System;
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using System.Runtime.ConstrainedExecution;
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using System.Threading;
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using System.Threading.Tasks;
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using System.Runtime.ConstrainedExecution;
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namespace Umbraco.Cms.Core
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namespace Umbraco.Cms.Core;
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// https://devblogs.microsoft.com/pfxteam/building-async-coordination-primitives-part-6-asynclock/
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//
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// notes:
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// - this is NOT a reader/writer lock
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// - this is NOT a recursive lock
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//
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// using a named Semaphore here and not a Mutex because mutexes have thread
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// affinity which does not work with async situations
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//
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// it is important that managed code properly release the Semaphore before
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// going down else it will maintain the lock - however note that when the
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// whole process (w3wp.exe) goes down and all handles to the Semaphore have
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// been closed, the Semaphore system object is destroyed - so in any case
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// an iisreset should clean up everything
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//
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public class SystemLock
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{
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// https://devblogs.microsoft.com/pfxteam/building-async-coordination-primitives-part-6-asynclock/
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//
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// notes:
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// - this is NOT a reader/writer lock
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// - this is NOT a recursive lock
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//
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// using a named Semaphore here and not a Mutex because mutexes have thread
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// affinity which does not work with async situations
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//
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// it is important that managed code properly release the Semaphore before
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// going down else it will maintain the lock - however note that when the
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// whole process (w3wp.exe) goes down and all handles to the Semaphore have
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// been closed, the Semaphore system object is destroyed - so in any case
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// an iisreset should clean up everything
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//
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public class SystemLock
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private readonly IDisposable? _releaser;
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private readonly Task<IDisposable>? _releaserTask;
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private readonly SemaphoreSlim? _semaphore;
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private readonly Semaphore? _semaphore2;
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public SystemLock()
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: this(null)
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{
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private readonly SemaphoreSlim? _semaphore;
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private readonly Semaphore? _semaphore2;
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private readonly IDisposable? _releaser;
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private readonly Task<IDisposable>? _releaserTask;
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}
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public SystemLock()
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: this(null)
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{ }
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public SystemLock(string? name)
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public SystemLock(string? name)
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{
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// WaitOne() waits until count > 0 then decrements count
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// Release() increments count
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// initial count: the initial count value
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// maximum count: the max value of count, and then Release() throws
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if (string.IsNullOrWhiteSpace(name))
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{
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// WaitOne() waits until count > 0 then decrements count
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// Release() increments count
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// initial count: the initial count value
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// maximum count: the max value of count, and then Release() throws
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// anonymous semaphore
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// use one unique releaser, that will not release the semaphore when finalized
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// because the semaphore is destroyed anyway if the app goes down
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_semaphore = new SemaphoreSlim(1, 1); // create a local (to the app domain) semaphore
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_releaser = new SemaphoreSlimReleaser(_semaphore);
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_releaserTask = Task.FromResult(_releaser);
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}
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else
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{
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// named semaphore
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// use dedicated releasers, that will release the semaphore when finalized
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// because the semaphore is system-wide and we cannot leak counts
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_semaphore2 = new Semaphore(1, 1, name); // create a system-wide named semaphore
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}
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}
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if (string.IsNullOrWhiteSpace(name))
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public IDisposable? Lock()
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{
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if (_semaphore != null)
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{
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_semaphore.Wait();
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}
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else
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{
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_semaphore2?.WaitOne();
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}
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return _releaser ?? CreateReleaser(); // anonymous vs named
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}
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private IDisposable? CreateReleaser() =>
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// for anonymous semaphore, use the unique releaser, else create a new one
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_semaphore != null
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? _releaser // (IDisposable)new SemaphoreSlimReleaser(_semaphore)
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: new NamedSemaphoreReleaser(_semaphore2);
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public IDisposable? Lock(int millisecondsTimeout)
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{
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var entered = _semaphore != null
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? _semaphore.Wait(millisecondsTimeout)
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: _semaphore2?.WaitOne(millisecondsTimeout);
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if (entered == false)
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{
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throw new TimeoutException("Failed to enter the lock within timeout.");
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}
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return _releaser ?? CreateReleaser(); // anonymous vs named
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}
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// note - before making those classes some structs, read
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// about "impure methods" and mutating readonly structs...
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private class NamedSemaphoreReleaser : CriticalFinalizerObject, IDisposable
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{
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private readonly Semaphore? _semaphore;
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// This code added to correctly implement the disposable pattern.
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private bool _disposedValue; // To detect redundant calls
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internal NamedSemaphoreReleaser(Semaphore? semaphore) => _semaphore = semaphore;
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// we WANT to release the semaphore because it's a system object, ie a critical
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// non-managed resource - and if it is not released then noone else can acquire
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// the lock - so we inherit from CriticalFinalizerObject which means that the
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// finalizer "should" run in all situations - there is always a chance that it
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// does not run and the semaphore remains "acquired" but then chances are the
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// whole process (w3wp.exe...) is going down, at which point the semaphore will
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// be destroyed by Windows.
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// however, the semaphore is a managed object, and so when the finalizer runs it
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// might have been finalized already, and then we get a, ObjectDisposedException
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// in the finalizer - which is bad.
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// in order to prevent this we do two things
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// - use a GCHandler to ensure the semaphore is still there when the finalizer
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// runs, so we can actually release it
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// - wrap the finalizer code in a try...catch to make sure it never throws
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~NamedSemaphoreReleaser()
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{
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try
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{
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// anonymous semaphore
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// use one unique releaser, that will not release the semaphore when finalized
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// because the semaphore is destroyed anyway if the app goes down
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_semaphore = new SemaphoreSlim(1, 1); // create a local (to the app domain) semaphore
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_releaser = new SemaphoreSlimReleaser(_semaphore);
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_releaserTask = Task.FromResult(_releaser);
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Dispose(false);
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}
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else
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catch
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{
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// named semaphore
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// use dedicated releasers, that will release the semaphore when finalized
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// because the semaphore is system-wide and we cannot leak counts
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_semaphore2 = new Semaphore(1, 1, name); // create a system-wide named semaphore
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// we do NOT want the finalizer to throw - never ever
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}
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}
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private IDisposable? CreateReleaser()
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public void Dispose()
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{
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// for anonymous semaphore, use the unique releaser, else create a new one
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return _semaphore != null
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? _releaser // (IDisposable)new SemaphoreSlimReleaser(_semaphore)
|
||||
: new NamedSemaphoreReleaser(_semaphore2);
|
||||
Dispose(true);
|
||||
GC.SuppressFinalize(this); // finalize will not run
|
||||
}
|
||||
|
||||
public IDisposable? Lock()
|
||||
private void Dispose(bool disposing)
|
||||
{
|
||||
if (_semaphore != null)
|
||||
_semaphore.Wait();
|
||||
else
|
||||
_semaphore2?.WaitOne();
|
||||
return _releaser ?? CreateReleaser(); // anonymous vs named
|
||||
}
|
||||
|
||||
public IDisposable? Lock(int millisecondsTimeout)
|
||||
{
|
||||
var entered = _semaphore != null
|
||||
? _semaphore.Wait(millisecondsTimeout)
|
||||
: _semaphore2?.WaitOne(millisecondsTimeout);
|
||||
if (entered == false)
|
||||
throw new TimeoutException("Failed to enter the lock within timeout.");
|
||||
return _releaser ?? CreateReleaser(); // anonymous vs named
|
||||
}
|
||||
|
||||
// note - before making those classes some structs, read
|
||||
// about "impure methods" and mutating readonly structs...
|
||||
|
||||
private class NamedSemaphoreReleaser : CriticalFinalizerObject, IDisposable
|
||||
{
|
||||
private readonly Semaphore? _semaphore;
|
||||
|
||||
internal NamedSemaphoreReleaser(Semaphore? semaphore)
|
||||
{
|
||||
_semaphore = semaphore;
|
||||
}
|
||||
|
||||
#region IDisposable Support
|
||||
|
||||
// This code added to correctly implement the disposable pattern.
|
||||
|
||||
private bool disposedValue = false; // To detect redundant calls
|
||||
|
||||
public void Dispose()
|
||||
{
|
||||
Dispose(true);
|
||||
GC.SuppressFinalize(this); // finalize will not run
|
||||
}
|
||||
|
||||
private void Dispose(bool disposing)
|
||||
{
|
||||
if (!disposedValue)
|
||||
{
|
||||
try
|
||||
{
|
||||
_semaphore?.Release();
|
||||
}
|
||||
finally
|
||||
{
|
||||
try
|
||||
{
|
||||
_semaphore?.Dispose();
|
||||
}
|
||||
catch { }
|
||||
}
|
||||
disposedValue = true;
|
||||
}
|
||||
}
|
||||
|
||||
// we WANT to release the semaphore because it's a system object, ie a critical
|
||||
// non-managed resource - and if it is not released then noone else can acquire
|
||||
// the lock - so we inherit from CriticalFinalizerObject which means that the
|
||||
// finalizer "should" run in all situations - there is always a chance that it
|
||||
// does not run and the semaphore remains "acquired" but then chances are the
|
||||
// whole process (w3wp.exe...) is going down, at which point the semaphore will
|
||||
// be destroyed by Windows.
|
||||
|
||||
// however, the semaphore is a managed object, and so when the finalizer runs it
|
||||
// might have been finalized already, and then we get a, ObjectDisposedException
|
||||
// in the finalizer - which is bad.
|
||||
|
||||
// in order to prevent this we do two things
|
||||
// - use a GCHandler to ensure the semaphore is still there when the finalizer
|
||||
// runs, so we can actually release it
|
||||
// - wrap the finalizer code in a try...catch to make sure it never throws
|
||||
|
||||
~NamedSemaphoreReleaser()
|
||||
if (!_disposedValue)
|
||||
{
|
||||
try
|
||||
{
|
||||
Dispose(false);
|
||||
_semaphore?.Release();
|
||||
}
|
||||
catch
|
||||
finally
|
||||
{
|
||||
// we do NOT want the finalizer to throw - never ever
|
||||
try
|
||||
{
|
||||
_semaphore?.Dispose();
|
||||
}
|
||||
catch
|
||||
{
|
||||
}
|
||||
}
|
||||
|
||||
_disposedValue = true;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
#endregion
|
||||
private class SemaphoreSlimReleaser : IDisposable
|
||||
{
|
||||
private readonly SemaphoreSlim _semaphore;
|
||||
|
||||
internal SemaphoreSlimReleaser(SemaphoreSlim semaphore) => _semaphore = semaphore;
|
||||
|
||||
~SemaphoreSlimReleaser() => Dispose(false);
|
||||
|
||||
public void Dispose()
|
||||
{
|
||||
Dispose(true);
|
||||
GC.SuppressFinalize(this);
|
||||
}
|
||||
|
||||
private class SemaphoreSlimReleaser : IDisposable
|
||||
private void Dispose(bool disposing)
|
||||
{
|
||||
private readonly SemaphoreSlim _semaphore;
|
||||
|
||||
internal SemaphoreSlimReleaser(SemaphoreSlim semaphore)
|
||||
if (disposing)
|
||||
{
|
||||
_semaphore = semaphore;
|
||||
}
|
||||
|
||||
public void Dispose()
|
||||
{
|
||||
Dispose(true);
|
||||
GC.SuppressFinalize(this);
|
||||
}
|
||||
|
||||
private void Dispose(bool disposing)
|
||||
{
|
||||
if (disposing)
|
||||
{
|
||||
// normal
|
||||
_semaphore.Release();
|
||||
}
|
||||
}
|
||||
|
||||
~SemaphoreSlimReleaser()
|
||||
{
|
||||
Dispose(false);
|
||||
// normal
|
||||
_semaphore.Release();
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
Reference in New Issue
Block a user