/* * Copyright (c) Contributors, http://opensimulator.org/ * See CONTRIBUTORS.TXT for a full list of copyright holders. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * Neither the name of the OpenSimulator Project nor the * names of its contributors may be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ using System.Collections.Generic; using System.Threading; namespace OpenSim.Framework { public class BlockingQueue<T> { private readonly Queue<T> m_pqueue = new Queue<T>(); private readonly Queue<T> m_queue = new Queue<T>(); private readonly object m_queueSync = new object(); public void PriorityEnqueue(T value) { lock (m_queueSync) { m_pqueue.Enqueue(value); Monitor.Pulse(m_queueSync); } } public void Enqueue(T value) { lock (m_queueSync) { m_queue.Enqueue(value); Monitor.Pulse(m_queueSync); } } public T Dequeue() { lock (m_queueSync) { while (m_queue.Count < 1 && m_pqueue.Count < 1) { Monitor.Wait(m_queueSync); } if (m_pqueue.Count > 0) return m_pqueue.Dequeue(); if (m_queue.Count > 0) return m_queue.Dequeue(); return default(T); } } public T Dequeue(int msTimeout) { lock (m_queueSync) { if (m_queue.Count < 1 && m_pqueue.Count < 1) { if(!Monitor.Wait(m_queueSync, msTimeout)) return default(T); } if (m_pqueue.Count > 0) return m_pqueue.Dequeue(); if (m_queue.Count > 0) return m_queue.Dequeue(); return default(T); } } /// <summary> /// Indicate whether this queue contains the given item. /// </summary> /// <remarks> /// This method is not thread-safe. Do not rely on the result without consistent external locking. /// </remarks> public bool Contains(T item) { lock (m_queueSync) { if (m_queue.Count < 1 && m_pqueue.Count < 1) return false; if (m_pqueue.Contains(item)) return true; return m_queue.Contains(item); } } /// <summary> /// Return a count of the number of requests on this queue. /// </summary> public int Count() { lock (m_queueSync) return m_queue.Count + m_pqueue.Count; } /// <summary> /// Return the array of items on this queue. /// </summary> /// <remarks> /// This method is not thread-safe. Do not rely on the result without consistent external locking. /// </remarks> public T[] GetQueueArray() { lock (m_queueSync) { if (m_queue.Count < 1 && m_pqueue.Count < 1) return new T[0]; return m_queue.ToArray(); } } public void Clear() { lock (m_queueSync) { m_pqueue.Clear(); m_queue.Clear(); Monitor.Pulse(m_queueSync); } } } }