/// <summary>Rents a <see cref="Int32TaskSocketAsyncEventArgs"/> for immediate use.</summary>
/// <param name="isReceive">true if this instance will be used for a receive; false if for sends.</param>
private Int32TaskSocketAsyncEventArgs RentSocketAsyncEventArgs(bool isReceive)
{
// Get any cached SocketAsyncEventArg we may have.
CachedTaskEventArgs cea = LazyInitializer.EnsureInitialized(ref _cachedTaskEventArgs);
Int32TaskSocketAsyncEventArgs saea = isReceive ?
Interlocked.Exchange(ref cea.Receive, s_rentedInt32Sentinel) :
Interlocked.Exchange(ref cea.Send, s_rentedInt32Sentinel);
if (saea == s_rentedInt32Sentinel)
{
// An instance was once created (or is currently being created elsewhere), but some other
// concurrent operation is using it. Since we can store at most one, and since an individual
// APM operation is less expensive than creating a new SAEA and using it only once, we simply
// return null, for a caller to fall back to using an APM implementation.
return(null);
}
if (saea == null)
{
// No instance has been created yet, so create one.
saea = new Int32TaskSocketAsyncEventArgs();
saea.Completed += isReceive ? ReceiveCompletedHandler : SendCompletedHandler;
}
return(saea);
}
/// <summary>Dispose of any cached <see cref="Int32TaskSocketAsyncEventArgs"/> instances.</summary>
private void DisposeCachedTaskSocketAsyncEventArgs()
{
CachedTaskEventArgs cea = _cachedTaskEventArgs;
if (cea != null)
{
Interlocked.Exchange(ref cea.Accept, s_rentedSocketSentinel)?.Dispose();
Interlocked.Exchange(ref cea.Receive, s_rentedInt32Sentinel)?.Dispose();
Interlocked.Exchange(ref cea.Send, s_rentedInt32Sentinel)?.Dispose();
}
}
