[2] | 1 | #region License Information
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| 2 | /* HeuristicLab
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| 3 | * Copyright (C) 2002-2008 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
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| 4 | *
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| 5 | * This file is part of HeuristicLab.
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| 6 | *
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| 7 | * HeuristicLab is free software: you can redistribute it and/or modify
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| 8 | * it under the terms of the GNU General Public License as published by
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| 9 | * the Free Software Foundation, either version 3 of the License, or
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| 10 | * (at your option) any later version.
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| 11 | *
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| 12 | * HeuristicLab is distributed in the hope that it will be useful,
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| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of
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| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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| 15 | * GNU General Public License for more details.
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| 16 | *
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| 17 | * You should have received a copy of the GNU General Public License
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| 18 | * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
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| 19 | */
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| 20 | #endregion
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| 21 |
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| 22 | using System;
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| 23 | using System.Collections.Generic;
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| 24 | using System.Text;
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| 25 | using System.Reflection;
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| 26 | using System.IO;
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| 27 | using System.Diagnostics;
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[2481] | 28 | using System.Linq;
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[2527] | 29 | using System.Security;
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[2] | 30 |
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[2481] | 31 |
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| 32 | namespace HeuristicLab.PluginInfrastructure.Manager {
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[2503] | 33 | /// <summary>
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| 34 | /// Discovers all installed plugins in the plugin directory. Checks correctness of plugin meta-data and if
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| 35 | /// all plugin files are available and checks plugin dependencies.
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| 36 | /// </summary>
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| 37 | internal sealed class PluginValidator : MarshalByRefObject {
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[2489] | 38 | internal event EventHandler<PluginInfrastructureEventArgs> PluginLoaded;
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[2] | 39 |
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[2481] | 40 | private Dictionary<PluginDescription, List<string>> pluginDependencies;
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[2] | 41 |
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[2481] | 42 | private List<ApplicationDescription> applications;
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| 43 | internal IEnumerable<ApplicationDescription> Applications {
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[2] | 44 | get {
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[2503] | 45 | if (string.IsNullOrEmpty(PluginDir)) throw new InvalidOperationException("PluginDir is not set.");
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[2497] | 46 | if (applications == null) DiscoverAndCheckPlugins();
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[2481] | 47 | return applications;
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[2] | 48 | }
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| 49 | }
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| 50 |
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[2481] | 51 | private IEnumerable<PluginDescription> plugins;
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| 52 | internal IEnumerable<PluginDescription> Plugins {
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[2] | 53 | get {
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[2503] | 54 | if (string.IsNullOrEmpty(PluginDir)) throw new InvalidOperationException("PluginDir is not set.");
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[2497] | 55 | if (plugins == null) DiscoverAndCheckPlugins();
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[2481] | 56 | return plugins;
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[29] | 57 | }
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| 58 | }
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| 59 |
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[2504] | 60 | internal string PluginDir { get; set; }
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[2] | 61 |
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[2504] | 62 | internal PluginValidator() {
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[2481] | 63 | this.pluginDependencies = new Dictionary<PluginDescription, List<string>>();
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[2488] | 64 |
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[2497] | 65 | // ReflectionOnlyAssemblyResolveEvent must be handled because we load assemblies from the plugin path
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| 66 | // (which is not listed in the default assembly lookup locations)
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[2488] | 67 | AppDomain.CurrentDomain.ReflectionOnlyAssemblyResolve += ReflectionOnlyAssemblyResolveEventHandler;
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[2] | 68 | }
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| 69 |
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[2488] | 70 | private Assembly ReflectionOnlyAssemblyResolveEventHandler(object sender, ResolveEventArgs args) {
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| 71 | return Assembly.ReflectionOnlyLoad(args.Name);
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| 72 | }
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[2] | 73 |
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[2488] | 74 |
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[2] | 75 | /// <summary>
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| 76 | /// Init first clears all internal datastructures (including plugin lists)
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| 77 | /// 1. All assemblies in the plugins directory are loaded into the reflection only context.
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[2503] | 78 | /// 2. The validator checks if all necessary files for each plugin are available.
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| 79 | /// 3. The validator builds the tree of plugin descriptions (dependencies)
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| 80 | /// 4. The validator checks if all dependencies for each plugin are ok.
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[2481] | 81 | /// 5. All plugins for which there are no dependencies missing are loaded into the execution context.
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| 82 | /// 6. Each loaded plugin (all assemblies) is searched for a types that implement IPlugin
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| 83 | /// then one instance of each IPlugin type is activated and the OnLoad hook is called.
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| 84 | /// 7. All types implementing IApplication are discovered
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[2] | 85 | /// </summary>
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[2503] | 86 | internal void DiscoverAndCheckPlugins() {
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[2] | 87 | pluginDependencies.Clear();
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| 88 |
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[2527] | 89 | IEnumerable<Assembly> reflectionOnlyAssemblies = ReflectionOnlyLoadDlls(PluginDir);
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[2481] | 90 | IEnumerable<PluginDescription> pluginDescriptions = GatherPluginDescriptions(reflectionOnlyAssemblies);
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| 91 | CheckPluginFiles(pluginDescriptions);
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[2] | 92 |
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[2527] | 93 | CheckPluginAssemblies(pluginDescriptions);
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| 94 |
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[2481] | 95 | // a full list of plugin descriptions is available now we can build the dependency tree
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| 96 | BuildDependencyTree(pluginDescriptions);
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| 97 |
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| 98 | // recursively check if all necessary plugins are available and not disabled
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| 99 | // disable plugins with missing or disabled dependencies
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| 100 | CheckPluginDependencies(pluginDescriptions);
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| 101 |
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[2488] | 102 | // mark all plugins as enabled that were not disabled in CheckPluginFiles or CheckPluginDependencies
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| 103 | foreach (var desc in pluginDescriptions)
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| 104 | if (desc.PluginState != PluginState.Disabled)
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| 105 | desc.Enable();
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| 106 |
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[2481] | 107 | // test full loading (in contrast to reflection only loading) of plugins
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| 108 | // disables plugins that are not loaded correctly
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| 109 | LoadPlugins(pluginDescriptions);
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| 110 |
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| 111 | plugins = pluginDescriptions;
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| 112 | DiscoverApplications();
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| 113 | }
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| 114 |
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| 115 | private void DiscoverApplications() {
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| 116 | applications = new List<ApplicationDescription>();
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[2] | 117 |
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[2488] | 118 | foreach (IApplication application in GetApplications()) {
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[2504] | 119 | Type appType = application.GetType();
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| 120 | ApplicationAttribute attr = (from x in appType.GetCustomAttributes(typeof(ApplicationAttribute), false)
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| 121 | select (ApplicationAttribute)x).Single();
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[2481] | 122 | ApplicationDescription info = new ApplicationDescription();
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[2] | 123 | info.Name = application.Name;
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[2504] | 124 | info.Version = appType.Assembly.GetName().Version;
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[2] | 125 | info.Description = application.Description;
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[2504] | 126 | info.AutoRestart = attr.RestartOnErrors;
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| 127 | info.DeclaringAssemblyName = appType.Assembly.GetName().Name;
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| 128 | info.DeclaringTypeName = appType.Namespace + "." + application.GetType().Name;
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[2] | 129 |
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[29] | 130 | applications.Add(info);
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[2] | 131 | }
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| 132 | }
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| 133 |
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[2504] | 134 | private static IEnumerable<IApplication> GetApplications() {
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[2488] | 135 | return from asm in AppDomain.CurrentDomain.GetAssemblies()
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| 136 | from t in asm.GetTypes()
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| 137 | where typeof(IApplication).IsAssignableFrom(t) &&
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| 138 | !t.IsAbstract && !t.IsInterface && !t.HasElementType
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| 139 | select (IApplication)Activator.CreateInstance(t);
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| 140 | }
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| 141 |
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[2527] | 142 | private static IEnumerable<Assembly> ReflectionOnlyLoadDlls(string baseDir) {
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[2] | 143 | List<Assembly> assemblies = new List<Assembly>();
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[2527] | 144 | // recursively load .dll files in subdirectories
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| 145 | foreach (string dirName in Directory.GetDirectories(baseDir)) {
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| 146 | assemblies.AddRange(ReflectionOnlyLoadDlls(dirName));
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| 147 | }
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[2481] | 148 | // try to load each .dll file in the plugin directory into the reflection only context
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[2527] | 149 | foreach (string filename in Directory.GetFiles(baseDir, "*.dll")) {
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[535] | 150 | try {
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[2481] | 151 | assemblies.Add(Assembly.ReflectionOnlyLoadFrom(filename));
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[1229] | 152 | }
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[2503] | 153 | catch (BadImageFormatException) { } // just ignore the case that the .dll file is not a CLR assembly (e.g. a native dll)
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[2527] | 154 | catch (FileLoadException) { }
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| 155 | catch (SecurityException) { }
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[2] | 156 | }
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| 157 | return assemblies;
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| 158 | }
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| 159 |
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[2527] | 160 | /// <summary>
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| 161 | /// Checks if all plugin assemblies can be loaded. If an assembly can't be loaded the plugin is disabled.
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| 162 | /// </summary>
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| 163 | /// <param name="pluginDescriptions"></param>
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| 164 | private void CheckPluginAssemblies(IEnumerable<PluginDescription> pluginDescriptions) {
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| 165 | foreach (var desc in pluginDescriptions.Where(x => x.PluginState != PluginState.Disabled)) {
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| 166 | try {
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| 167 | foreach (var asm in desc.Assemblies) {
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| 168 | Assembly.ReflectionOnlyLoadFrom(asm);
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| 169 | }
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| 170 | }
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| 171 | catch (BadImageFormatException) {
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| 172 | // disable the plugin
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| 173 | desc.Disable();
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| 174 | }
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| 175 | catch (FileNotFoundException) {
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| 176 | // disable the plugin
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| 177 | desc.Disable();
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| 178 | }
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| 179 | catch (FileLoadException) {
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| 180 | // disable the plugin
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| 181 | desc.Disable();
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| 182 | }
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| 183 | catch (ArgumentException) {
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| 184 | // disable the plugin
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| 185 | desc.Disable();
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| 186 | }
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| 187 | catch (SecurityException) {
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| 188 | // disable the plugin
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| 189 | desc.Disable();
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| 190 | }
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| 191 | }
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| 192 | }
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| 193 |
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| 194 |
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[2481] | 195 | // find all types implementing IPlugin in the reflectionOnlyAssemblies and create a list of plugin descriptions
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| 196 | // the dependencies in the plugin descriptions are not yet set correctly because we need to create
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| 197 | // the full list of all plugin descriptions first
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| 198 | private IEnumerable<PluginDescription> GatherPluginDescriptions(IEnumerable<Assembly> assemblies) {
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| 199 | List<PluginDescription> pluginDescriptions = new List<PluginDescription>();
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[1229] | 200 | foreach (Assembly assembly in assemblies) {
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[2] | 201 | // GetExportedTypes throws FileNotFoundException when a referenced assembly
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| 202 | // of the current assembly is missing.
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| 203 | try {
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[2527] | 204 | // if there is a type that implements IPlugin
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| 205 | // use AssemblyQualifiedName to compare the types because we can't directly
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| 206 | // compare ReflectionOnly types and execution types
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| 207 | var assemblyPluginDescriptions = from t in assembly.GetExportedTypes()
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| 208 | where !t.IsAbstract && t.GetInterfaces().Any(x => x.AssemblyQualifiedName == typeof(IPlugin).AssemblyQualifiedName)
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| 209 | select GetPluginDescription(t);
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| 210 | pluginDescriptions.AddRange(assemblyPluginDescriptions);
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[1229] | 211 | }
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[2497] | 212 | // ignore exceptions. Just don't yield a plugin description when an exception is thrown
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[2489] | 213 | catch (FileNotFoundException) {
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[1229] | 214 | }
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[2489] | 215 | catch (FileLoadException) {
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[2] | 216 | }
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[2489] | 217 | catch (InvalidPluginException) {
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[1395] | 218 | }
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[2] | 219 | }
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[2481] | 220 | return pluginDescriptions;
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[2] | 221 | }
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| 222 |
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| 223 | /// <summary>
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| 224 | /// Extracts plugin information for this type.
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| 225 | /// Reads plugin name, list and type of files and dependencies of the plugin. This information is necessary for
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| 226 | /// plugin dependency checking before plugin activation.
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| 227 | /// </summary>
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| 228 | /// <param name="t"></param>
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[2481] | 229 | private PluginDescription GetPluginDescription(Type pluginType) {
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[2] | 230 | // get all attributes of that type
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[2481] | 231 | IList<CustomAttributeData> attributes = CustomAttributeData.GetCustomAttributes(pluginType);
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[2] | 232 | List<string> pluginAssemblies = new List<string>();
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| 233 | List<string> pluginDependencies = new List<string>();
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[29] | 234 | List<string> pluginFiles = new List<string>();
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[2481] | 235 | string pluginName = null;
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[2513] | 236 | string pluginDescription = null;
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[2481] | 237 | // iterate through all custom attributes and search for attributed that we are interested in
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[1229] | 238 | foreach (CustomAttributeData attributeData in attributes) {
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[2488] | 239 | if (IsAttributeDataForType(attributeData, typeof(PluginAttribute))) {
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[2481] | 240 | pluginName = (string)attributeData.ConstructorArguments[0].Value;
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[2513] | 241 | if (attributeData.ConstructorArguments.Count() == 2) {
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| 242 | pluginDescription = (string)attributeData.ConstructorArguments[1].Value;
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| 243 | } else pluginDescription = pluginName;
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[2481] | 244 | } else if (IsAttributeDataForType(attributeData, typeof(PluginDependencyAttribute))) {
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| 245 | pluginDependencies.Add((string)attributeData.ConstructorArguments[0].Value);
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| 246 | } else if (IsAttributeDataForType(attributeData, typeof(PluginFileAttribute))) {
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| 247 | string pluginFileName = (string)attributeData.ConstructorArguments[0].Value;
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| 248 | PluginFileType fileType = (PluginFileType)attributeData.ConstructorArguments[1].Value;
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[2527] | 249 | pluginFiles.Add(Path.GetFullPath(Path.Combine(PluginDir, pluginFileName)));
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[2481] | 250 | if (fileType == PluginFileType.Assembly) {
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[2527] | 251 | pluginAssemblies.Add(Path.GetFullPath(Path.Combine(PluginDir, pluginFileName)));
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[2] | 252 | }
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| 253 | }
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| 254 | }
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| 255 |
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[2504] | 256 | var buildDates = from attr in CustomAttributeData.GetCustomAttributes(pluginType.Assembly)
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| 257 | where IsAttributeDataForType(attr, typeof(AssemblyBuildDateAttribute))
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| 258 | select (string)attr.ConstructorArguments[0].Value;
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| 259 |
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[29] | 260 | // minimal sanity check of the attribute values
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[2517] | 261 | if (!string.IsNullOrEmpty(pluginName) &&
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[2481] | 262 | pluginFiles.Count > 0 &&
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[2504] | 263 | pluginAssemblies.Count > 0 &&
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| 264 | buildDates.Count() == 1) {
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[2481] | 265 | // create a temporary PluginDescription that contains the attribute values
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| 266 | PluginDescription info = new PluginDescription();
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[29] | 267 | info.Name = pluginName;
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[2513] | 268 | info.Description = pluginDescription;
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[2481] | 269 | info.Version = pluginType.Assembly.GetName().Version;
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[2504] | 270 | info.BuildDate = DateTime.Parse(buildDates.Single(), System.Globalization.CultureInfo.InvariantCulture);
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[2481] | 271 | info.AddAssemblies(pluginAssemblies);
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| 272 | info.AddFiles(pluginFiles);
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| 273 |
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[29] | 274 | this.pluginDependencies[info] = pluginDependencies;
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[2481] | 275 | return info;
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[2] | 276 | } else {
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[2481] | 277 | throw new InvalidPluginException("Invalid metadata in plugin " + pluginType.ToString());
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[2] | 278 | }
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| 279 | }
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| 280 |
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[2504] | 281 | private static bool IsAttributeDataForType(CustomAttributeData attributeData, Type attributeType) {
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[2481] | 282 | return attributeData.Constructor.DeclaringType.AssemblyQualifiedName == attributeType.AssemblyQualifiedName;
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| 283 | }
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| 284 |
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| 285 | // builds a dependency tree of all plugin descriptions
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| 286 | // searches matching plugin descriptions based on the list of dependency names for each plugin
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| 287 | // and sets the dependencies in the plugin descriptions
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| 288 | private void BuildDependencyTree(IEnumerable<PluginDescription> pluginDescriptions) {
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| 289 | foreach (var desc in pluginDescriptions) {
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| 290 | foreach (string pluginName in pluginDependencies[desc]) {
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| 291 | var matchingDescriptions = pluginDescriptions.Where(x => x.Name == pluginName);
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| 292 | if (matchingDescriptions.Count() > 0) {
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[2517] | 293 | desc.AddDependency(matchingDescriptions.Single());
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[2481] | 294 | } else {
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| 295 | // no plugin description that matches the dependency name is available => plugin is disabled
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[2488] | 296 | desc.Disable();
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[2481] | 297 | }
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[29] | 298 | }
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[2481] | 299 | }
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| 300 | }
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[37] | 301 |
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[2481] | 302 | private void CheckPluginDependencies(IEnumerable<PluginDescription> pluginDescriptions) {
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| 303 | foreach (PluginDescription pluginDescription in pluginDescriptions.Where(x => x.PluginState != PluginState.Disabled)) {
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| 304 | if (IsAnyDependencyDisabled(pluginDescription)) {
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[2488] | 305 | pluginDescription.Disable();
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[29] | 306 | }
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| 307 | }
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| 308 | }
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| 309 |
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| 310 |
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[2481] | 311 | private bool IsAnyDependencyDisabled(PluginDescription descr) {
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| 312 | if (descr.PluginState == PluginState.Disabled) return true;
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| 313 | foreach (PluginDescription dependency in descr.Dependencies) {
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| 314 | if (IsAnyDependencyDisabled(dependency)) return true;
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[2] | 315 | }
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[2481] | 316 | return false;
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[2] | 317 | }
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| 318 |
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[2481] | 319 | private void LoadPlugins(IEnumerable<PluginDescription> pluginDescriptions) {
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[2] | 320 | // load all loadable plugins (all dependencies available) into the execution context
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[2517] | 321 | foreach (var desc in PluginDescriptionIterator.IterateDependenciesBottomUp(pluginDescriptions
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[2488] | 322 | .Where(x => x.PluginState != PluginState.Disabled))) {
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[2481] | 323 | List<Type> types = new List<Type>();
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| 324 | foreach (string assembly in desc.Assemblies) {
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| 325 | var asm = Assembly.LoadFrom(assembly);
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| 326 | foreach (Type t in asm.GetTypes()) {
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| 327 | if (typeof(IPlugin).IsAssignableFrom(t)) {
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| 328 | types.Add(t);
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| 329 | }
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[2] | 330 | }
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| 331 | }
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| 332 |
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[2481] | 333 | foreach (Type pluginType in types) {
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[1229] | 334 | if (!pluginType.IsAbstract && !pluginType.IsInterface && !pluginType.HasElementType) {
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[2] | 335 | IPlugin plugin = (IPlugin)Activator.CreateInstance(pluginType);
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[2481] | 336 | plugin.OnLoad();
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[2503] | 337 | OnPluginLoaded(new PluginInfrastructureEventArgs("Plugin loaded", plugin.Name));
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[2] | 338 | }
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| 339 | }
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[2489] | 340 | desc.Load();
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[2] | 341 | }
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| 342 | }
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[91] | 343 |
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[2481] | 344 | // checks if all declared plugin files are actually available and disables plugins with missing files
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[2527] | 345 | private void CheckPluginFiles(IEnumerable<PluginDescription> pluginDescriptions) {
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[2481] | 346 | foreach (PluginDescription desc in pluginDescriptions) {
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| 347 | if (!CheckPluginFiles(desc)) {
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[2488] | 348 | desc.Disable();
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[29] | 349 | }
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[2] | 350 | }
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| 351 | }
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| 352 |
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[2527] | 353 | private bool CheckPluginFiles(PluginDescription pluginDescription) {
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[2504] | 354 | foreach (string filename in pluginDescription.Files) {
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[2527] | 355 | if (!FileLiesInDirectory(PluginDir, filename) ||
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| 356 | !File.Exists(filename)) {
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[2] | 357 | return false;
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| 358 | }
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| 359 | }
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| 360 | return true;
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| 361 | }
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| 362 |
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[2527] | 363 | private static bool FileLiesInDirectory(string dir, string fileName) {
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| 364 | var basePath = Path.GetFullPath(dir);
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| 365 | return Path.GetFullPath(fileName).StartsWith(basePath);
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| 366 | }
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| 367 |
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[2503] | 368 | internal void OnPluginLoaded(PluginInfrastructureEventArgs e) {
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[2489] | 369 | if (PluginLoaded != null)
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[2503] | 370 | PluginLoaded(this, e);
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[2489] | 371 | }
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| 372 |
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[1189] | 373 | /// <summary>
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[2497] | 374 | /// Initializes the life time service with an infinite lease time.
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[1189] | 375 | /// </summary>
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| 376 | /// <returns><c>null</c>.</returns>
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[2] | 377 | public override object InitializeLifetimeService() {
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| 378 | return null;
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| 379 | }
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| 380 | }
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| 381 | }
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