/* * 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; using System.Collections.Generic; using System.Threading; using System.Reflection; using System.Xml; using System.Diagnostics; using System.Xml.Schema; using System.Xml.Serialization; using log4net; using OpenMetaverse; namespace OpenSim.Framework { /// <summary> /// A dictionary containing task inventory items. Indexed by item UUID. /// </summary> /// <remarks> /// This class is not thread safe. Callers must synchronize on Dictionary methods or Clone() this object before /// iterating over it. /// </remarks> public class TaskInventoryDictionary : Dictionary<UUID, TaskInventoryItem>, ICloneable, IXmlSerializable { // private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType); private static XmlSerializer tiiSerializer = new XmlSerializer(typeof (TaskInventoryItem)); private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType); private Thread LockedByThread; // private string WriterStack; // private Dictionary<Thread, string> ReadLockers = // new Dictionary<Thread, string>(); /// <value> /// An advanced lock for inventory data /// </value> private volatile System.Threading.ReaderWriterLockSlim m_itemLock = new System.Threading.ReaderWriterLockSlim(); /// <summary> /// Are we readlocked by the calling thread? /// </summary> public bool IsReadLockedByMe() { if (m_itemLock.RecursiveReadCount > 0) { return true; } else { return false; } } /// <summary> /// Lock our inventory list for reading (many can read, one can write) /// </summary> public void LockItemsForRead(bool locked) { if (locked) { if (m_itemLock.IsWriteLockHeld && LockedByThread != null) { if (!LockedByThread.IsAlive) { //Locked by dead thread, reset. m_itemLock = new System.Threading.ReaderWriterLockSlim(); } } if (m_itemLock.RecursiveReadCount > 0) { m_log.Error("[TaskInventoryDictionary] Recursive read lock requested. This should not happen and means something needs to be fixed. For now though, it's safe to continue."); try { // That call stack is useful for end users only. RealProgrammers need a full dump. Commented. // StackTrace stackTrace = new StackTrace(); // get call stack // StackFrame[] stackFrames = stackTrace.GetFrames(); // get method calls (frames) // // // write call stack method names // foreach (StackFrame stackFrame in stackFrames) // { // m_log.Error("[SceneObjectGroup.m_parts] "+(stackFrame.GetMethod().Name)); // write method name // } // The below is far more useful // System.Console.WriteLine("------------------------------------------"); // System.Console.WriteLine("My call stack:\n" + Environment.StackTrace); // System.Console.WriteLine("------------------------------------------"); // foreach (KeyValuePair<Thread, string> kvp in ReadLockers) // { // System.Console.WriteLine("Locker name {0} call stack:\n" + kvp.Value, kvp.Key.Name); // System.Console.WriteLine("------------------------------------------"); // } } catch {} m_itemLock.ExitReadLock(); } if (m_itemLock.RecursiveWriteCount > 0) { m_log.Error("[TaskInventoryDictionary] Recursive write lock requested. This should not happen and means something needs to be fixed."); // try // { // System.Console.WriteLine("------------------------------------------"); // System.Console.WriteLine("My call stack:\n" + Environment.StackTrace); // System.Console.WriteLine("------------------------------------------"); // System.Console.WriteLine("Locker's call stack:\n" + WriterStack); // System.Console.WriteLine("------------------------------------------"); // } // catch // {} m_itemLock.ExitWriteLock(); } while (!m_itemLock.TryEnterReadLock(60000)) { m_log.Error("Thread lock detected while trying to aquire READ lock in TaskInventoryDictionary. Locked by thread " + LockedByThread.Name + ". I'm going to try to solve the thread lock automatically to preserve region stability, but this needs to be fixed."); //if (m_itemLock.IsWriteLockHeld) //{ m_itemLock = new System.Threading.ReaderWriterLockSlim(); // System.Console.WriteLine("------------------------------------------"); // System.Console.WriteLine("My call stack:\n" + Environment.StackTrace); // System.Console.WriteLine("------------------------------------------"); // System.Console.WriteLine("Locker's call stack:\n" + WriterStack); // System.Console.WriteLine("------------------------------------------"); // LockedByThread = null; // ReadLockers.Clear(); //} } // ReadLockers[Thread.CurrentThread] = Environment.StackTrace; } else { if (m_itemLock.RecursiveReadCount>0) { m_itemLock.ExitReadLock(); } // if (m_itemLock.RecursiveReadCount == 0) // ReadLockers.Remove(Thread.CurrentThread); } } /// <summary> /// Lock our inventory list for writing (many can read, one can write) /// </summary> public void LockItemsForWrite(bool locked) { if (locked) { //Enter a write lock, wait indefinately for one to open. if (m_itemLock.RecursiveReadCount > 0) { m_log.Error("[TaskInventoryDictionary] Recursive read lock requested. This should not happen and means something needs to be fixed. For now though, it's safe to continue."); m_itemLock.ExitReadLock(); } if (m_itemLock.RecursiveWriteCount > 0) { m_log.Error("[TaskInventoryDictionary] Recursive write lock requested. This should not happen and means something needs to be fixed."); m_itemLock.ExitWriteLock(); } while (!m_itemLock.TryEnterWriteLock(60000)) { if (m_itemLock.IsWriteLockHeld) { m_log.Error("Thread lock detected while trying to aquire WRITE lock in TaskInventoryDictionary. Locked by thread " + LockedByThread.Name + ". I'm going to try to solve the thread lock automatically to preserve region stability, but this needs to be fixed."); // System.Console.WriteLine("------------------------------------------"); // System.Console.WriteLine("My call stack:\n" + Environment.StackTrace); // System.Console.WriteLine("------------------------------------------"); // System.Console.WriteLine("Locker's call stack:\n" + WriterStack); // System.Console.WriteLine("------------------------------------------"); } else { m_log.Error("Thread lock detected while trying to aquire WRITE lock in TaskInventoryDictionary. Locked by a reader. I'm going to try to solve the thread lock automatically to preserve region stability, but this needs to be fixed."); // System.Console.WriteLine("------------------------------------------"); // System.Console.WriteLine("My call stack:\n" + Environment.StackTrace); // System.Console.WriteLine("------------------------------------------"); // foreach (KeyValuePair<Thread, string> kvp in ReadLockers) // { // System.Console.WriteLine("Locker name {0} call stack:\n" + kvp.Value, kvp.Key.Name); // System.Console.WriteLine("------------------------------------------"); // } } m_itemLock = new System.Threading.ReaderWriterLockSlim(); // ReadLockers.Clear(); } LockedByThread = Thread.CurrentThread; // WriterStack = Environment.StackTrace; } else { if (m_itemLock.RecursiveWriteCount > 0) { m_itemLock.ExitWriteLock(); } } } #region ICloneable Members public Object Clone() { TaskInventoryDictionary clone = new TaskInventoryDictionary(); m_itemLock.EnterReadLock(); foreach (UUID uuid in Keys) { clone.Add(uuid, (TaskInventoryItem) this[uuid].Clone()); } m_itemLock.ExitReadLock(); return clone; } #endregion // The alternative of simply serializing the list doesn't appear to work on mono, since // we get a // // System.TypeInitializationException: An exception was thrown by the type initializer for OpenSim.Framework.TaskInventoryDictionary ---> System.ArgumentOutOfRangeException: < 0 // Parameter name: length // at System.String.Substring (Int32 startIndex, Int32 length) [0x00088] in /build/buildd/mono-1.2.4/mcs/class/corlib/System/String.cs:381 // at System.Xml.Serialization.TypeTranslator.GetTypeData (System.Type runtimeType, System.String xmlDataType) [0x001f6] in /build/buildd/mono-1.2.4/mcs/class/System.XML/System.Xml.Serialization/TypeTranslator.cs:217 // ... // private static XmlSerializer tiiSerializer // = new XmlSerializer(typeof(Dictionary<UUID, TaskInventoryItem>.ValueCollection)); // see IXmlSerializable #region IXmlSerializable Members public XmlSchema GetSchema() { return null; } // see IXmlSerializable public void ReadXml(XmlReader reader) { // m_log.DebugFormat("[TASK INVENTORY]: ReadXml current node before actions, {0}", reader.Name); if (!reader.IsEmptyElement) { reader.Read(); while (tiiSerializer.CanDeserialize(reader)) { TaskInventoryItem item = (TaskInventoryItem) tiiSerializer.Deserialize(reader); Add(item.ItemID, item); //m_log.DebugFormat("[TASK INVENTORY]: Instanted prim item {0}, {1} from xml", item.Name, item.ItemID); } // m_log.DebugFormat("[TASK INVENTORY]: Instantiated {0} prim items in total from xml", Count); } // else // { // m_log.DebugFormat("[TASK INVENTORY]: Skipping empty element {0}", reader.Name); // } // For some .net implementations, this last read is necessary so that we advance beyond the end tag // of the element wrapping this object so that the rest of the serialization can complete normally. reader.Read(); // m_log.DebugFormat("[TASK INVENTORY]: ReadXml current node after actions, {0}", reader.Name); } // see IXmlSerializable public void WriteXml(XmlWriter writer) { lock (this) { foreach (TaskInventoryItem item in Values) { tiiSerializer.Serialize(writer, item); } } //tiiSerializer.Serialize(writer, Values); } #endregion // see ICloneable } }