/* * 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 OpenSim 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.IO; using System.Collections.Generic; using System.Reflection; using log4net; using Mono.Addins; namespace OpenSim.Framework { /// /// Exception thrown if an incorrect number of plugins are loaded /// public class PluginConstraintViolatedException : Exception { public PluginConstraintViolatedException () : base() {} public PluginConstraintViolatedException (string msg) : base(msg) {} public PluginConstraintViolatedException (string msg, Exception e) : base(msg, e) {} } /// /// Classes wishing to impose constraints on plugin loading must implement /// this class and pass it to PluginLoader AddConstraint() /// public interface IPluginConstraint { bool Fail (string extpoint); string Message { get; } } /// /// Generic Plugin Loader /// public class PluginLoader : IDisposable where T : IPlugin { private const int max_loadable_plugins = 10000; private List loaded = new List(); private List extpoints = new List(); private PluginInitialiserBase initialiser; private Dictionary constraints = new Dictionary(); private static bool runonce = false; private static readonly ILog log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType); public PluginInitialiserBase Initialiser { set { initialiser = value; } get { return initialiser; } } public List Plugins { get { return loaded; } } public PluginLoader () { Initialiser = new PluginInitialiserBase(); initialise_plugin_dir_ ("."); } public PluginLoader (PluginInitialiserBase init) { Initialiser = init; initialise_plugin_dir_ ("."); } public PluginLoader (PluginInitialiserBase init, string dir) { Initialiser = init; initialise_plugin_dir_ (dir); } public void AddExtensionPoint (string extpoint) { extpoints.Add (extpoint); } public void AddConstraint (string extpoint, IPluginConstraint cons) { constraints.Add (extpoint, cons); } public void Load (string extpoint) { AddExtensionPoint (extpoint); Load(); } public void Load () { log.Info("[PLUGINS]: Begin Loading " + AddinManager.Registry.RegistryPath); foreach (string ext in extpoints) { log.Info("[PLUGINS]: Loading extension point " + ext); if (constraints.ContainsKey (ext)) { IPluginConstraint cons = constraints [ext]; if (cons.Fail (ext)) throw new PluginConstraintViolatedException (cons.Message); } ExtensionNodeList ns = AddinManager.GetExtensionNodes (ext); foreach (TypeExtensionNode n in ns) { T p = (T) n.CreateInstance(); Initialiser.Initialise (p); Plugins.Add (p); log.Info("[PLUGINS]: Loading plugin " + n.Path); } } } public void Dispose () { foreach (T p in Plugins) p.Dispose (); } private void initialise_plugin_dir_ (string dir) { if (runonce == true) return; log.Info("[PLUGINS]: Initialzing " + dir); clear_registry_(); suppress_console_output_ (true); AddinManager.Initialize (dir); AddinManager.Registry.Update (null); suppress_console_output_ (false); runonce = true; } private void clear_registry_ () { // The Mono addin manager (in Mono.Addins.dll version 0.2.0.0) // occasionally seems to corrupt its addin cache // Hence, as a temporary solution we'll remove it before each startup if (Directory.Exists("addin-db-000")) Directory.Delete("addin-db-000", true); if (Directory.Exists("addin-db-001")) Directory.Delete("addin-db-001", true); } private static TextWriter prev_console_; public void suppress_console_output_ (bool save) { if (save) { prev_console_ = System.Console.Out; System.Console.SetOut(new StreamWriter(Stream.Null)); } else { if (prev_console_ != null) System.Console.SetOut(prev_console_); } } } public class PluginCountConstraint : IPluginConstraint { private int min; private int max; public PluginCountConstraint (int exact) { min = exact; max = exact; } public PluginCountConstraint (int minimum, int maximum) { min = minimum; max = maximum; } public string Message { get { return "The number of plugins is constrained to the interval [" + min + ", " + max + "]"; } } public bool Fail (string extpoint) { ExtensionNodeList ns = AddinManager.GetExtensionNodes (extpoint); if ((ns.Count < min) || (ns.Count > max)) return true; else return false; } } public class PluginFilenameConstraint : IPluginConstraint { private string filename; public PluginFilenameConstraint (string name) { filename = name; } public string Message { get { return "The plugin must have the following name: " + filename; } } public bool Fail (string extpoint) { ExtensionNodeList ns = AddinManager.GetExtensionNodes (extpoint); if (ns.Count != 1) return true; string[] path = ns[0].Path.Split('/'); if (path [path.Length-1] == filename) return false; return true; } } }