/// <summary>
/// Returns the next element from the queue without removing it
/// </summary>
/// <returns>A pointer to the next element from the queue</returns>
/// <exception cref="InvalidOperationException">If the queue is empty</exception>
public T *Peek()
{
AtomicNode *root = AcquireRoot();
bool empty = (root->Next == 0);
var payload = (T *)(empty ? 0 : ((AtomicNode *)root->Next)->Payload);
ReleaseRoot(root);
if (empty)
{
throw new InvalidOperationException("Queue is empty");
}
return(payload);
}
/// <summary>
/// Add an element to the queue
/// </summary>
/// <param name="payload">A pointer to the element to be added</param>
public void Enqueue(T *payload)
{
var node = (long)Acquire((long)payload, 0);
AtomicNode *root = AcquireRoot();
var last = (AtomicNode *)root->Payload;
root->Payload = node;
if (last != null)
{
last->Next = node;
}
if (root->Next == 0)
{
// Queue was empty
root->Next = node;
}
ReleaseRoot(root);
}
