/// <summary>
/// Adds an object to the end of the queue.
/// </summary>
/// <param name="item">the object to add to the queue</param>
public void Enqueue(T item)
{
SingleLinkNode <T> oldTail = null;
var newNode = new SingleLinkNode <T> {
Item = item
};
var newNodeWasAdded = false;
while (!newNodeWasAdded)
{
oldTail = _tail;
var oldTailNext = oldTail.Next;
if (_tail != oldTail)
{
continue;
}
if (oldTailNext == null)
{
newNodeWasAdded =
Interlocked.CompareExchange(ref _tail.Next, newNode, null) == null;
}
else
{
Interlocked.CompareExchange(ref _tail, oldTailNext, oldTail);
}
}
Interlocked.CompareExchange(ref _tail, newNode, oldTail);
Interlocked.Increment(ref _count);
}
/// <summary>
/// Clears the queue.
/// </summary>
/// <remarks>This method is not thread-safe.</remarks>
public void Clear()
{
var currentNode = _head;
while (currentNode != null)
{
var tempNode = currentNode;
currentNode = currentNode.Next;
tempNode.Item = default(T);
tempNode.Next = null;
}
_head = new SingleLinkNode <T>();
_tail = _head;
_count = 0;
}
/// <summary>
/// Default constructor.
/// </summary>
public LockFreeQueue()
{
_head = new SingleLinkNode <T>();
_tail = _head;
}