1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
|
/*
* 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.Collections;
using System.Collections.Generic;
using System.Reflection;
using System.Text;
using log4net;
using OpenSim.ScriptEngine.Shared;
using IScript=OpenSim.Region.ScriptEngine.Shared.ScriptBase.IScript;
namespace OpenSim.ScriptEngine.Components.DotNetEngine.Scheduler
{
public class ScriptLoader : IScriptLoader
{
//
// This class does AppDomain handling and loading/unloading of
// scripts in it. It is instanced in "ScriptEngine" and controlled
// from "ScriptManager"
//
// 1. Create a new AppDomain if old one is full (or doesn't exist)
// 2. Load scripts into AppDomain
// 3. Unload scripts from AppDomain (stopping them and marking
// them as inactive)
// 4. Unload AppDomain completely when all scripts in it has stopped
//
public string Name { get { return "SECS.DotNetEngine.Scheduler.ScriptLoader"; } }
private int maxScriptsPerAppDomain = 10;
// Internal list of all AppDomains
private List<AppDomainStructure> appDomains =
new List<AppDomainStructure>();
private Dictionary<string, AppDomainStructure> AppDomainFiles = new Dictionary<string, AppDomainStructure>();
public readonly string[] AssembliesInAppDomain = new string[] { "OpenSim.ScriptEngine.Shared.Script.dll", "OpenSim.Region.ScriptEngine.Shared.dll" };
internal static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
// Structure to keep track of data around AppDomain
private class AppDomainStructure
{
public AppDomain CurrentAppDomain; // The AppDomain itself
public int ScriptsLoaded; // Number of scripts loaded into AppDomain
public int ScriptsWaitingUnload; // Number of dead scripts
}
// Current AppDomain
private AppDomainStructure currentAD;
private object getLock = new object(); // Mutex
private object freeLock = new object(); // Mutex
// Find a free AppDomain, creating one if necessary
private AppDomainStructure GetFreeAppDomain()
{
lock (getLock)
{
// Current full?
if (currentAD != null &&
currentAD.ScriptsLoaded >= maxScriptsPerAppDomain)
{
// Add it to AppDomains list and empty current
appDomains.Add(currentAD);
currentAD = null;
}
// No current
if (currentAD == null)
{
// Create a new current AppDomain
currentAD = new AppDomainStructure();
currentAD.CurrentAppDomain = PrepareNewAppDomain();
}
return currentAD;
}
}
private int AppDomainNameCount;
public ScriptAssemblies.IScript LoadScript(ScriptStructure script)
{
// Find next available AppDomain to put it in
AppDomainStructure FreeAppDomain;
// If we already have loaded file, then reuse that AppDomains
if (AppDomainFiles.ContainsKey(script.AssemblyFileName))
FreeAppDomain = AppDomainFiles[script.AssemblyFileName];
else
FreeAppDomain = GetFreeAppDomain();
// Set script object AppDomain
script.AppDomain = FreeAppDomain.CurrentAppDomain;
// Create instance of script
ScriptAssemblies.IScript mbrt = (ScriptAssemblies.IScript)
FreeAppDomain.CurrentAppDomain.CreateInstanceFromAndUnwrap(
script.AssemblyFileName, "ScriptAssemblies.Script");
//, true, BindingFlags.CreateInstance, null);
FreeAppDomain.ScriptsLoaded++;
return mbrt;
}
// Create and prepare a new AppDomain for scripts
private AppDomain PrepareNewAppDomain()
{
// Create and prepare a new AppDomain
AppDomainNameCount++;
// TODO: Currently security match current appdomain
// Construct and initialize settings for a second AppDomain.
AppDomainSetup ads = new AppDomainSetup();
ads.ApplicationBase = AppDomain.CurrentDomain.BaseDirectory;
ads.DisallowBindingRedirects = true;
ads.DisallowCodeDownload = true;
ads.LoaderOptimization = LoaderOptimization.MultiDomainHost;
ads.ShadowCopyFiles = "false"; // Disable shadowing
ads.ConfigurationFile =
AppDomain.CurrentDomain.SetupInformation.ConfigurationFile;
AppDomain AD = AppDomain.CreateDomain("ScriptAppDomain_" +
AppDomainNameCount, null, ads);
foreach (string file in AssembliesInAppDomain)
{
m_log.InfoFormat("[{0}] AppDomain Loading: \"{1}\"->\"{2}\".", Name, file,
AssemblyName.GetAssemblyName(file).ToString());
AD.Load(AssemblyName.GetAssemblyName(file));
}
// Return the new AppDomain
return AD;
}
// Unload appdomains that are full and have only dead scripts
private void UnloadAppDomains()
{
lock (freeLock)
{
// Go through all
foreach (AppDomainStructure ads in new ArrayList(appDomains))
{
// Don't process current AppDomain
if (ads.CurrentAppDomain != currentAD.CurrentAppDomain)
{
// Not current AppDomain
// Is number of unloaded bigger or equal to number of loaded?
if (ads.ScriptsLoaded <= ads.ScriptsWaitingUnload)
{
// Remove from internal list
appDomains.Remove(ads);
// Unload
AppDomain.Unload(ads.CurrentAppDomain);
}
}
}
}
}
// Increase "dead script" counter for an AppDomain
public void StopScript(AppDomain ad)
{
lock (freeLock)
{
// Check if it is current AppDomain
if (currentAD.CurrentAppDomain == ad)
{
// Yes - increase
currentAD.ScriptsWaitingUnload++;
return;
}
// Lopp through all AppDomains
foreach (AppDomainStructure ads in new ArrayList(appDomains))
{
if (ads.CurrentAppDomain == ad)
{
// Found it
ads.ScriptsWaitingUnload++;
break;
}
}
}
UnloadAppDomains(); // Outsite lock, has its own GetLock
}
}
}
|
