Struct AsyncLock

Unified representation of asynchronous exclusive lock, semaphore lock, read lock, write lock or upgradeable read lock.

Implements

IDisposable

IEquatable<AsyncLock>

IAsyncDisposable

Inherited Members

object.Equals(object, object)

object.GetType()

object.ReferenceEquals(object, object)

Namespace: DotNext.Threading

Assembly: DotNext.Threading.dll

Syntax

public struct AsyncLock : IDisposable, IEquatable<AsyncLock>, IAsyncDisposable

Remarks

Lock acquisition is asynchronous operation. Note that non-blocking asynchronous locks are not intersected with their blocking alternatives except semaphore. It means that exclusive lock obtained in blocking manner doesn't prevent acquisition of asynchronous lock obtained in non-blocking manner.

Methods

AcquireAsync(CancellationToken)

Acquires the lock asynchronously.

Declaration

public readonly ValueTask<AsyncLock.Holder> AcquireAsync(CancellationToken token)

Parameters

Type	Name	Description
CancellationToken	token	The token that can be used to abort acquisition operation.

Returns

Type	Description
ValueTask<AsyncLock.Holder>	The task returning the acquired lock holder.

Exceptions

Type	Condition
OperationCanceledException	The operation has been canceled.

AcquireAsync(TimeSpan, CancellationToken)

Acquires the lock asynchronously.

Declaration

public readonly ValueTask<AsyncLock.Holder> AcquireAsync(TimeSpan timeout, CancellationToken token = default)

Parameters

Type	Name	Description
TimeSpan	timeout	The interval to wait for the lock.
CancellationToken	token	The token that can be used to abort acquisition operation.

Returns

Type	Description
ValueTask<AsyncLock.Holder>	The task returning the acquired lock holder.

Exceptions

Type	Condition
TimeoutException	The lock cannot be acquired during the specified amount of time.
OperationCanceledException	The operation has been canceled.

Dispose()

Destroy this lock and dispose underlying lock object if it is owned by the given lock.

Declaration

public void Dispose()

Remarks

If the given lock is an owner of the underlying lock object then this method will call Dispose() on it; otherwise, the underlying lock object will not be destroyed. As a result, this lock is not usable after calling of this method.

DisposeAsync()

Destroy this lock and asynchronously dispose underlying lock object if it is owned by the given lock.

Declaration

public ValueTask DisposeAsync()

Returns

Type	Description
ValueTask	The task representing asynchronous execution of this method.

Remarks

If the given lock is an owner of the underlying lock object then this method will call DisposeAsync() or Dispose() on it; otherwise, the underlying lock object will not be destroyed. As a result, this lock is not usable after calling of this method.

Equals(AsyncLock)

Determines whether this lock object is the same as other lock.

Declaration

public readonly bool Equals(AsyncLock other)

Parameters

Type	Name	Description
AsyncLock	other	Other lock to compare.

Returns

Type	Description
bool	true if this lock is the same as the specified lock; otherwise, false.

Equals(object?)

Determines whether this lock object is the same as other lock.

Declaration

public override readonly bool Equals(object? other)

Parameters

Type	Name	Description
object	other	Other lock to compare.

Returns

Type	Description
bool	true if this lock is the same as the specified lock; otherwise, false.

Overrides

ValueType.Equals(object)

Exclusive()

Creates exclusive asynchronous lock but doesn't acquire it.

Declaration

public static AsyncLock Exclusive()

Returns

Type	Description
AsyncLock	Exclusive asynchronous lock.

Remarks

Constructed lock owns the exclusive lock instance.

See Also

AsyncExclusiveLock

Exclusive(AsyncExclusiveLock)

Wraps exclusive lock into the unified representation of asynchronous lock.

Declaration

public static AsyncLock Exclusive(AsyncExclusiveLock @lock)

Parameters

Type	Name	Description
AsyncExclusiveLock	lock	The lock object to be wrapped.

Returns

Type	Description
AsyncLock	Exclusive asynchronous lock.

Exceptions

Type	Condition
ArgumentNullException	lock is null.

Exclusive(AsyncSharedLock)

Creates strong (exclusive) lock but doesn't acquire it.

Declaration

public static AsyncLock Exclusive(AsyncSharedLock @lock)

Parameters

Type	Name	Description
AsyncSharedLock	lock	The shared lock instance.

Returns

Type	Description
AsyncLock	Exclusive lock.

Exceptions

Type	Condition
ArgumentNullException	lock is null.

GetHashCode()

Computes hash code of this lock.

Declaration

public override readonly int GetHashCode()

Returns

Type	Description
int	The hash code of this lock.

Overrides

ValueType.GetHashCode()

ReadLock(AsyncReaderWriterLock)

Creates read lock but doesn't acquire it.

Declaration

public static AsyncLock ReadLock(AsyncReaderWriterLock rwLock)

Parameters

Type	Name	Description
AsyncReaderWriterLock	rwLock	Read/write lock source.

Returns

Type	Description
AsyncLock	Reader lock.

Exceptions

Type	Condition
ArgumentNullException	rwLock is null.

Semaphore(int, int)

Creates semaphore-based lock but doesn't acquire the lock.

Declaration

public static AsyncLock Semaphore(int initialCount, int maxCount)

Parameters

Type	Name	Description
int	initialCount	The initial number of requests for the semaphore that can be granted concurrently.
int	maxCount	The maximum number of requests for the semaphore that can be granted concurrently.

Returns

Type	Description
AsyncLock	The lock representing semaphore.

Remarks

Constructed lock owns the semaphore instance.

Semaphore(SemaphoreSlim)

Wraps semaphore instance into the unified representation of the lock.

Declaration

public static AsyncLock Semaphore(SemaphoreSlim semaphore)

Parameters

Type	Name	Description
SemaphoreSlim	semaphore	The semaphore to wrap into lock object.

Returns

Type	Description
AsyncLock	The lock representing semaphore.

Exceptions

Type	Condition
ArgumentNullException	semaphore is null.

ToString()

Returns actual type of this lock in the form of the string.

Declaration

public override readonly string ToString()

Returns

Type	Description
string	The actual type of this lock.

Overrides

ValueType.ToString()

TryAcquireAsync(TimeSpan, CancellationToken)

Tries to acquire the lock asynchronously.

Declaration

public readonly ValueTask<AsyncLock.Holder> TryAcquireAsync(TimeSpan timeout, CancellationToken token = default)

Parameters

Type	Name	Description
TimeSpan	timeout	The interval to wait for the lock.
CancellationToken	token	The token that can be used to abort acquisition operation.

Returns

Type	Description
ValueTask<AsyncLock.Holder>	The task returning the acquired lock holder; or empty lock holder if lock has not been acquired.

Exceptions

Type	Condition
OperationCanceledException	The operation has been canceled.

Weak(AsyncSharedLock)

Creates weak lock but doesn't acquire it.

Declaration

public static AsyncLock Weak(AsyncSharedLock @lock)

Parameters

Type	Name	Description
AsyncSharedLock	lock	The shared lock instance.

Returns

Type	Description
AsyncLock	Weak lock.

Exceptions

Type	Condition
ArgumentNullException	lock is null.

WriteLock(AsyncReaderWriterLock, bool)

Creates write lock but doesn't acquire it.

Declaration

public static AsyncLock WriteLock(AsyncReaderWriterLock rwLock, bool upgrade = false)

Parameters

Type	Name	Description
AsyncReaderWriterLock	rwLock	Read/write lock source.
bool	upgrade	true to upgrade from read lock; otherwise, false.

Returns

Type	Description
AsyncLock	Write-only lock.

Exceptions

Type	Condition
ArgumentNullException	rwLock is null.

Operators

operator ==(in AsyncLock, in AsyncLock)

Determines whether two locks are the same.

Declaration

public static bool operator ==(in AsyncLock first, in AsyncLock second)

Parameters

Type	Name	Description
AsyncLock	first	The first lock to compare.
AsyncLock	second	The second lock to compare.

Returns

Type	Description
bool	true, if both are the same; otherwise, false.

operator !=(in AsyncLock, in AsyncLock)

Determines whether two locks are not the same.

Declaration

public static bool operator !=(in AsyncLock first, in AsyncLock second)

Parameters

Type	Name	Description
AsyncLock	first	The first lock to compare.
AsyncLock	second	The second lock to compare.

Returns

Type	Description
bool	true, if both are not the same; otherwise, false.

Implements

IDisposable

IEquatable<T>

IAsyncDisposable

Extension Methods

BasicExtensions.IsBetween<T, TLowerBound, TUpperBound>(T, TLowerBound, TUpperBound)

BasicExtensions.IsOneOf<T>(T, ReadOnlySpan<T>)

Collection.ToAsyncEnumerator<TEnumerator, T>(TEnumerator, CancellationToken)

Collection.ToClassicEnumerator<TEnumerator, T>(TEnumerator)

Enumerator.Skip<TEnumerator, T>(ref TEnumerator, int)

ExpressionBuilder.Const<T>(T)

See Also

Lock