1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/Utilities/PInvokeDelegateFactory.cs	Tue Jan 26 22:37:48 2010 +0000
     1.3 @@ -0,0 +1,118 @@
     1.4 +/*
     1.5 +  
     1.6 +  Version: MPL 1.1/GPL 2.0/LGPL 2.1
     1.7 +
     1.8 +  The contents of this file are subject to the Mozilla Public License Version
     1.9 +  1.1 (the "License"); you may not use this file except in compliance with
    1.10 +  the License. You may obtain a copy of the License at
    1.11 + 
    1.12 +  http://www.mozilla.org/MPL/
    1.13 +
    1.14 +  Software distributed under the License is distributed on an "AS IS" basis,
    1.15 +  WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
    1.16 +  for the specific language governing rights and limitations under the License.
    1.17 +
    1.18 +  The Original Code is the Open Hardware Monitor code.
    1.19 +
    1.20 +  The Initial Developer of the Original Code is 
    1.21 +  Michael Möller <m.moeller@gmx.ch>.
    1.22 +  Portions created by the Initial Developer are Copyright (C) 2009-2010
    1.23 +  the Initial Developer. All Rights Reserved.
    1.24 +
    1.25 +  Contributor(s):
    1.26 +
    1.27 +  Alternatively, the contents of this file may be used under the terms of
    1.28 +  either the GNU General Public License Version 2 or later (the "GPL"), or
    1.29 +  the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
    1.30 +  in which case the provisions of the GPL or the LGPL are applicable instead
    1.31 +  of those above. If you wish to allow use of your version of this file only
    1.32 +  under the terms of either the GPL or the LGPL, and not to allow others to
    1.33 +  use your version of this file under the terms of the MPL, indicate your
    1.34 +  decision by deleting the provisions above and replace them with the notice
    1.35 +  and other provisions required by the GPL or the LGPL. If you do not delete
    1.36 +  the provisions above, a recipient may use your version of this file under
    1.37 +  the terms of any one of the MPL, the GPL or the LGPL.
    1.38 + 
    1.39 +*/
    1.40 +
    1.41 +using System;
    1.42 +using System.Collections.Generic;
    1.43 +using System.Reflection;
    1.44 +using System.Reflection.Emit;
    1.45 +using System.Runtime.InteropServices;
    1.46 +
    1.47 +namespace OpenHardwareMonitor.Hardware {
    1.48 +
    1.49 +  public sealed class PInvokeDelegateFactory {
    1.50 +
    1.51 +    private static AssemblyBuilder assemblyBuilder;
    1.52 +    private static ModuleBuilder moduleBuilder;
    1.53 +
    1.54 +    private static IDictionary<DllImportAttribute, Type> wrapperTypes =
    1.55 +      new Dictionary<DllImportAttribute, Type>();
    1.56 +
    1.57 +    static PInvokeDelegateFactory() {
    1.58 +
    1.59 +      AssemblyName assemblyName = new AssemblyName();
    1.60 +      assemblyName.Name = "PInvokeDelegateFactoryInternalAssembly";
    1.61 +
    1.62 +      assemblyBuilder =
    1.63 +        AppDomain.CurrentDomain.DefineDynamicAssembly(assemblyName,
    1.64 +        AssemblyBuilderAccess.Run);
    1.65 +
    1.66 +      moduleBuilder = assemblyBuilder.DefineDynamicModule(
    1.67 +        "PInvokeDelegateFactoryInternalModule");
    1.68 +    }
    1.69 +
    1.70 +    private PInvokeDelegateFactory() { }
    1.71 +
    1.72 +    public static void CreateDelegate<T>(DllImportAttribute dllImportAttribute,
    1.73 +      out T newDelegate) where T : class 
    1.74 +    {
    1.75 +      Type wrapperType;
    1.76 +      wrapperTypes.TryGetValue(dllImportAttribute, out wrapperType);
    1.77 +
    1.78 +      if (wrapperType == null) {
    1.79 +        wrapperType = CreateWrapperType(typeof(T), dllImportAttribute);
    1.80 +        wrapperTypes.Add(dllImportAttribute, wrapperType);
    1.81 +      }
    1.82 +
    1.83 +      newDelegate = Delegate.CreateDelegate(typeof(T), wrapperType,
    1.84 +        dllImportAttribute.EntryPoint) as T;
    1.85 +    }
    1.86 +
    1.87 +
    1.88 +    private static Type CreateWrapperType(Type delegateType,
    1.89 +      DllImportAttribute dllImportAttribute) {
    1.90 +
    1.91 +      TypeBuilder typeBuilder = moduleBuilder.DefineType(
    1.92 +        "PInvokeDelegateFactoryInternalWrapperType" + wrapperTypes.Count);
    1.93 +
    1.94 +      MethodInfo methodInfo = delegateType.GetMethod("Invoke");
    1.95 +
    1.96 +      ParameterInfo[] parameterInfos = methodInfo.GetParameters();
    1.97 +      int parameterCount = parameterInfos.GetLength(0);
    1.98 +
    1.99 +      Type[] parameterTypes = new Type[parameterCount];
   1.100 +      for (int i = 0; i < parameterCount; i++)
   1.101 +        parameterTypes[i] = parameterInfos[i].ParameterType;
   1.102 +
   1.103 +      MethodBuilder methodBuilder = typeBuilder.DefinePInvokeMethod(
   1.104 +        dllImportAttribute.EntryPoint, dllImportAttribute.Value,
   1.105 +        MethodAttributes.Public | MethodAttributes.Static |
   1.106 +        MethodAttributes.PinvokeImpl, CallingConventions.Standard,
   1.107 +        methodInfo.ReturnType, parameterTypes,
   1.108 +        dllImportAttribute.CallingConvention,
   1.109 +        dllImportAttribute.CharSet);
   1.110 +
   1.111 +      foreach (ParameterInfo parameterInfo in parameterInfos)
   1.112 +        methodBuilder.DefineParameter(parameterInfo.Position + 1,
   1.113 +          parameterInfo.Attributes, parameterInfo.Name);
   1.114 +
   1.115 +      if (dllImportAttribute.PreserveSig)
   1.116 +        methodBuilder.SetImplementationFlags(MethodImplAttributes.PreserveSig);
   1.117 +
   1.118 +      return typeBuilder.CreateType();
   1.119 +    }
   1.120 +  }
   1.121 +}